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  • Plastic pollution accumulating in an area of the environment is considered "poorly reversible" if natural mineralization processes occurring there are slow and engineered remediation solutions are improbable. Should negative outcomes in these areas arise as a consequence of plastic pollution, they will be practically irreversible. Potential impacts from poorly reversible plastic pollution include changes to carbon and nutrient cycles; habitat changes within soils, sediments, and aquatic ecosystems; co-occurring biological impacts on endangered or keystone species; ecotoxicity; and related societal impacts. The rational response to the global threat posed by accumulating and poorly reversible plastic pollution is to rapidly reduce plastic emissions through reductions in consumption of virgin plastic materials, along with internationally coordinated strategies for waste management.Human activities are changing our environment. Along with climate change and a widespread loss of biodiversity, plastic pollution now plays a predominant role in altering ecosystems globally. Here, we review the occurrence of plastic ingestion by wildlife through evolutionary and ecological lenses and address the fundamental question of why living organisms ingest plastic. We unify evolutionary, ecological, and cognitive approaches under the evolutionary trap theory and identify three main factors that may drive plastic ingestion (i) the availability of plastics in the environment, (ii) an individual's acceptance threshold, and (iii) the overlap of cues given by natural foods and plastics.Plastic contamination of the environment is a global problem whose magnitude justifies the consideration of plastics as emergent geomaterials with chemistries not previously seen in Earth's history. At the elemental level, plastics are predominantly carbon. The comparison of plastic stocks and fluxes to those of carbon reveals that the quantities of plastics present in some ecosystems rival the quantity of natural organic carbon and suggests that geochemists should now consider plastics in their analyses. Acknowledging plastics as geomaterials and adopting geochemical insights and methods can expedite our understanding of plastics in the Earth system. Plastics also can be used as global-scale tracers to advance Earth system science.The mechanisms by which macrophages regulate energy storage remain poorly understood. We identify in a genetic screen a platelet-derived growth factor (PDGF)/vascular endothelial growth factor (VEGF)-family ortholog, Pvf3, that is produced by macrophages and is required for lipid storage in fat-body cells of Drosophila larvae. Genetic and pharmacological experiments indicate that the mouse Pvf3 ortholog PDGFcc, produced by adipose tissue-resident macrophages, controls lipid storage in adipocytes in a leptin receptor- and C-C chemokine receptor type 2-independent manner. PDGFcc production is regulated by diet and acts in a paracrine manner to control lipid storage in adipose tissues of newborn and adult ****. At the organismal level upon PDGFcc blockade, excess lipids are redirected toward thermogenesis in brown fat. These data identify a macrophage-dependent mechanism, conducive to the design of pharmacological interventions, that controls energy storage in metazoans.Large-scale human exome sequencing can identify rare protein-coding variants with a large impact on complex traits such as body adiposity. We sequenced the exomes of 645,626 individuals from the United Kingdom, the United States, and Mexico and estimated associations of rare coding variants with body mass index (BMI). We identified 16 genes with an exome-wide significant association with BMI, including those encoding five brain-expressed G protein-coupled receptors (CALCR, MC4R, GIPR, GPR151, and GPR75). Protein-truncating variants in GPR75 were observed in ~4/10,000 sequenced individuals and were associated with 1.8 kilograms per square meter lower BMI and 54% lower odds of obesity in the heterozygous state. https://www.selleckchem.com/products/pf-06650833.html Knock out of Gpr75 in **** resulted in resistance to weight gain and improved glycemic control in a high-fat diet model. Inhibition of GPR75 may provide a therapeutic strategy for obesity.Synthetic biological networks comprising fast, reversible reactions could enable engineering of new cellular behaviors that are not possible with slower regulation. Here, we created a bistable toggle switch in Saccharomyces cerevisiae using a cross-repression topology comprising 11 protein-protein phosphorylation elements. The toggle is ultrasensitive, can be induced to switch states in seconds, and exhibits long-term bistability. Motivated by our toggle's architecture and size, we developed a computational framework to search endogenous protein pathways for other large and similar bistable networks. Our framework helped us to identify and experimentally verify five formerly unreported endogenous networks that exhibit bistability. Building synthetic protein-protein networks will enable bioengineers to design fast sensing and processing systems, allow sophisticated regulation of cellular processes, and aid discovery of endogenous networks with particular functions.The plant male germline undergoes DNA methylation reprogramming, which methylates genes de novo and thereby alters gene expression and regulates meiosis. Here, we reveal the molecular mechanism underlying this reprogramming. We demonstrate that genic methylation in the male germline, from meiocytes to sperm, is established by 24-nucleotide small interfering RNAs (siRNAs) transcribed from transposons with imperfect sequence homology. These siRNAs are synthesized by meiocyte nurse cells (tapetum) through activity of CLSY3, a chromatin remodeler absent in other anther cells. Tapetal siRNAs govern germline methylation throughout the genome, including the inherited methylation patterns in sperm. Tapetum-derived siRNAs also silence germline transposons, safeguarding genome integrity. Our results reveal that tapetal siRNAs are sufficient to reconstitute germline methylation patterns and drive functional methylation reprogramming throughout the male germline.
    Plastic pollution accumulating in an area of the environment is considered "poorly reversible" if natural mineralization processes occurring there are slow and engineered remediation solutions are improbable. Should negative outcomes in these areas arise as a consequence of plastic pollution, they will be practically irreversible. Potential impacts from poorly reversible plastic pollution include changes to carbon and nutrient cycles; habitat changes within soils, sediments, and aquatic ecosystems; co-occurring biological impacts on endangered or keystone species; ecotoxicity; and related societal impacts. The rational response to the global threat posed by accumulating and poorly reversible plastic pollution is to rapidly reduce plastic emissions through reductions in consumption of virgin plastic materials, along with internationally coordinated strategies for waste management.Human activities are changing our environment. Along with climate change and a widespread loss of biodiversity, plastic pollution now plays a predominant role in altering ecosystems globally. Here, we review the occurrence of plastic ingestion by wildlife through evolutionary and ecological lenses and address the fundamental question of why living organisms ingest plastic. We unify evolutionary, ecological, and cognitive approaches under the evolutionary trap theory and identify three main factors that may drive plastic ingestion (i) the availability of plastics in the environment, (ii) an individual's acceptance threshold, and (iii) the overlap of cues given by natural foods and plastics.Plastic contamination of the environment is a global problem whose magnitude justifies the consideration of plastics as emergent geomaterials with chemistries not previously seen in Earth's history. At the elemental level, plastics are predominantly carbon. The comparison of plastic stocks and fluxes to those of carbon reveals that the quantities of plastics present in some ecosystems rival the quantity of natural organic carbon and suggests that geochemists should now consider plastics in their analyses. Acknowledging plastics as geomaterials and adopting geochemical insights and methods can expedite our understanding of plastics in the Earth system. Plastics also can be used as global-scale tracers to advance Earth system science.The mechanisms by which macrophages regulate energy storage remain poorly understood. We identify in a genetic screen a platelet-derived growth factor (PDGF)/vascular endothelial growth factor (VEGF)-family ortholog, Pvf3, that is produced by macrophages and is required for lipid storage in fat-body cells of Drosophila larvae. Genetic and pharmacological experiments indicate that the mouse Pvf3 ortholog PDGFcc, produced by adipose tissue-resident macrophages, controls lipid storage in adipocytes in a leptin receptor- and C-C chemokine receptor type 2-independent manner. PDGFcc production is regulated by diet and acts in a paracrine manner to control lipid storage in adipose tissues of newborn and adult mice. At the organismal level upon PDGFcc blockade, excess lipids are redirected toward thermogenesis in brown fat. These data identify a macrophage-dependent mechanism, conducive to the design of pharmacological interventions, that controls energy storage in metazoans.Large-scale human exome sequencing can identify rare protein-coding variants with a large impact on complex traits such as body adiposity. We sequenced the exomes of 645,626 individuals from the United Kingdom, the United States, and Mexico and estimated associations of rare coding variants with body mass index (BMI). We identified 16 genes with an exome-wide significant association with BMI, including those encoding five brain-expressed G protein-coupled receptors (CALCR, MC4R, GIPR, GPR151, and GPR75). Protein-truncating variants in GPR75 were observed in ~4/10,000 sequenced individuals and were associated with 1.8 kilograms per square meter lower BMI and 54% lower odds of obesity in the heterozygous state. https://www.selleckchem.com/products/pf-06650833.html Knock out of Gpr75 in mice resulted in resistance to weight gain and improved glycemic control in a high-fat diet model. Inhibition of GPR75 may provide a therapeutic strategy for obesity.Synthetic biological networks comprising fast, reversible reactions could enable engineering of new cellular behaviors that are not possible with slower regulation. Here, we created a bistable toggle switch in Saccharomyces cerevisiae using a cross-repression topology comprising 11 protein-protein phosphorylation elements. The toggle is ultrasensitive, can be induced to switch states in seconds, and exhibits long-term bistability. Motivated by our toggle's architecture and size, we developed a computational framework to search endogenous protein pathways for other large and similar bistable networks. Our framework helped us to identify and experimentally verify five formerly unreported endogenous networks that exhibit bistability. Building synthetic protein-protein networks will enable bioengineers to design fast sensing and processing systems, allow sophisticated regulation of cellular processes, and aid discovery of endogenous networks with particular functions.The plant male germline undergoes DNA methylation reprogramming, which methylates genes de novo and thereby alters gene expression and regulates meiosis. Here, we reveal the molecular mechanism underlying this reprogramming. We demonstrate that genic methylation in the male germline, from meiocytes to sperm, is established by 24-nucleotide small interfering RNAs (siRNAs) transcribed from transposons with imperfect sequence homology. These siRNAs are synthesized by meiocyte nurse cells (tapetum) through activity of CLSY3, a chromatin remodeler absent in other anther cells. Tapetal siRNAs govern germline methylation throughout the genome, including the inherited methylation patterns in sperm. Tapetum-derived siRNAs also silence germline transposons, safeguarding genome integrity. Our results reveal that tapetal siRNAs are sufficient to reconstitute germline methylation patterns and drive functional methylation reprogramming throughout the male germline.
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  • This report is on a 61-year-old patient with steroid therapy for rheumatoid arthritis and pain in the groin on both sides who got injections with hyaluronic acid in both hip joints. After 12 weeks the X-ray of the pelvis showed rapid progressive destruction of both hip joints.The helium ion microscope has emerged as a multifaceted instrument enabling a broad range of applications beyond imaging in which the finely focused helium ion beam is used for a variety of defect engineering, ion implantation, and nanofabrication tasks. Operation of the ion source with neon has extended the reach of this technology even further. This paper reviews the materials modification research that has been enabled by the helium ion microscope since its commercialization in 2007, ranging from fundamental studies of beam-sample effects, to the prototyping of new devices with features in the sub-10 nm domain.Silver nanowires (AgNWs) with ultrahigh purity and high yield were successfully synthesized by employing a modified facile polyol method using PVP as a capping and stabilizing agent. The reaction was carried out at a moderate temperature of 160 °C under mild stirring for about 3 h. The prepared AgNWs exhibited parallel alignment on a large scale and were characterized by UV-vis spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD), and PL spectroscopy. The luminescent AgNWs exhibited red emission, which was accredited to deep holes. The SEM results confirmed the formation of AgNWs of 3.3 to 4.7 µm in length with an average diameter of about 86 nm, that is, the aspect ratio values of the AgNWs exceeded 45. An ink consisting of hydroxyethyl cellulose (HEC) and AgNWs was transferred to polyethylene terephthalate (PET) films by simple mechanical pressing. The PET films retained transparency and flexibility after the ink coating. The maximum transmittance value of as-prepared PET films in the visible region was estimated to be about 92.5% with a sheet resistance value of ca. 20 Ω/sq. This makes the films a potential substitute to commonly used expensive indium tin oxide (ITO) in the field of flexible optoelectronics.Conjugated polymers (CPs) as photocatalysts have evoked substantial interest. Their geometries and physical (e.g., chemical and thermal stability and solubility), optical (e.g., light absorption range), and electronic properties (e.g., charge carrier mobility, redox potential, and exciton binding energy) can be easily tuned via structural design. In addition, they are of light weight (i.e., mainly composed of C, N, O, and S). To improve the photocatalytic performance of CPs and better understand the catalytic mechanisms, many strategies with respect to material design have been proposed. These include tuning the bandgap, enlarging the surface area, enabling more efficient separation of electron-hole pairs, and enhancing the charge carrier mobility. In particular, donor-acceptor (D-A) polymers were demonstrated as a promising platform to develop high-performance photocatalysts due to their easily tunable bandgaps, high charge carrier mobility, and efficient intramolecular charge transfer. In this minireview, recent advances of D-A polymers in photocatalytic hydrogen evolution are summarized with a particular focus on modulating the optical and electronic properties of CPs by varying the acceptor units. The challenges and prospects associated with D-A polymer-based photocatalysts are described as well.Platinum-carbon catalysts are widely used in the manufacturing of proton-exchange membrane fuel cells. Increasing Pt/C activity and stability is an urgent task and the optimization of their structure seems to be one of the possible solutions. In the present paper, Pt/C electrocatalysts containing small (2-2.6 nm) nanoparticles (NPs) of a similar size, uniformly distributed over the surface of a carbon support, were obtained by the original method of liquid-phase synthesis. A comparative study of the structural characteristics, catalytic activity in the oxygen electroreduction reaction (ORR), and durability of the synthesized catalysts, as well as their commercial analogs, was carried out. https://www.selleckchem.com/products/azd7545.html It was shown that the uniformity of the structural and morphological characteristics of Pt/C catalysts makes it possible to reduce the negative effect of the small size of NPs on their stability. As a result, the obtained catalysts were significantly superior to their commercial analogs regarding ORR activity, but not inferior to them in terms of stability.In order to effectively utilize the photovoltaic properties of gallium arsenide, its surface/interface needs to be properly prepared. In the experiments described here we examined eight different paths of GaAs surface treatment (cleaning, etching, passivation) which resulted in different external quantum efficiency (EQE) values of the tested photovoltaic (PV) cells. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) examinations were conducted to obtain structural details of the devices. X-ray photoelectron spectroscopy (XPS) with depth profiling was used to examine interface structure and changes in the elemental content and chemical bonds. The photoluminescence (PL) properties and bandgap measurements of the deposited layers were also reported. The highest EQE value was obtained for the samples initially etched with a citric acid-based etchant and, in the last preparation step, either passivated with ammonium sulfide aqueous solution or treated with ammonium hydroxide solution with no final passivation. Subsequent I-V measurements, however, confirmed that from these samples, only the sulfur-passivated ones provided the highest current density. The tested devices were fabricated by using the ALD method.This study aimed to reveal the differences in intestinal microbes in osteoporotic rats. The rats were divided into two groups the control and OP (osteoporosis) groups (n=6). Days 0 and 70 were set as the time points. The rats in the OP group underwent bilateral ovariectomy (OVX). Differences between the control and OP groups were determined by 16S rDNA analysis. The relative abundances of OTUs and alpha/beta diversities were determined at days 0 days and 70. The abundances of Verrucomicrobia at the phylum level and Aerococcus, Coprobacillus, Veillonella, Anaerobiospirillum, Flavobacterium, Comamonadaceae, Ohtaekwangia, etc., at the genus level were found to be different between the control_70d and OP_70d groups. KEGG ontology analysis showed that the function of lipid metabolism could be related to OP. The 16S rDNA analysis in the OP rats revealed that intestinal microbes take part in the processes of OP and could affect lipid metabolism. Further study of the relationship between OP and intestinal microbes is necessary, and the prospect for intestinal microbes is a potential treatment for OP.
    This report is on a 61-year-old patient with steroid therapy for rheumatoid arthritis and pain in the groin on both sides who got injections with hyaluronic acid in both hip joints. After 12 weeks the X-ray of the pelvis showed rapid progressive destruction of both hip joints.The helium ion microscope has emerged as a multifaceted instrument enabling a broad range of applications beyond imaging in which the finely focused helium ion beam is used for a variety of defect engineering, ion implantation, and nanofabrication tasks. Operation of the ion source with neon has extended the reach of this technology even further. This paper reviews the materials modification research that has been enabled by the helium ion microscope since its commercialization in 2007, ranging from fundamental studies of beam-sample effects, to the prototyping of new devices with features in the sub-10 nm domain.Silver nanowires (AgNWs) with ultrahigh purity and high yield were successfully synthesized by employing a modified facile polyol method using PVP as a capping and stabilizing agent. The reaction was carried out at a moderate temperature of 160 °C under mild stirring for about 3 h. The prepared AgNWs exhibited parallel alignment on a large scale and were characterized by UV-vis spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD), and PL spectroscopy. The luminescent AgNWs exhibited red emission, which was accredited to deep holes. The SEM results confirmed the formation of AgNWs of 3.3 to 4.7 µm in length with an average diameter of about 86 nm, that is, the aspect ratio values of the AgNWs exceeded 45. An ink consisting of hydroxyethyl cellulose (HEC) and AgNWs was transferred to polyethylene terephthalate (PET) films by simple mechanical pressing. The PET films retained transparency and flexibility after the ink coating. The maximum transmittance value of as-prepared PET films in the visible region was estimated to be about 92.5% with a sheet resistance value of ca. 20 Ω/sq. This makes the films a potential substitute to commonly used expensive indium tin oxide (ITO) in the field of flexible optoelectronics.Conjugated polymers (CPs) as photocatalysts have evoked substantial interest. Their geometries and physical (e.g., chemical and thermal stability and solubility), optical (e.g., light absorption range), and electronic properties (e.g., charge carrier mobility, redox potential, and exciton binding energy) can be easily tuned via structural design. In addition, they are of light weight (i.e., mainly composed of C, N, O, and S). To improve the photocatalytic performance of CPs and better understand the catalytic mechanisms, many strategies with respect to material design have been proposed. These include tuning the bandgap, enlarging the surface area, enabling more efficient separation of electron-hole pairs, and enhancing the charge carrier mobility. In particular, donor-acceptor (D-A) polymers were demonstrated as a promising platform to develop high-performance photocatalysts due to their easily tunable bandgaps, high charge carrier mobility, and efficient intramolecular charge transfer. In this minireview, recent advances of D-A polymers in photocatalytic hydrogen evolution are summarized with a particular focus on modulating the optical and electronic properties of CPs by varying the acceptor units. The challenges and prospects associated with D-A polymer-based photocatalysts are described as well.Platinum-carbon catalysts are widely used in the manufacturing of proton-exchange membrane fuel cells. Increasing Pt/C activity and stability is an urgent task and the optimization of their structure seems to be one of the possible solutions. In the present paper, Pt/C electrocatalysts containing small (2-2.6 nm) nanoparticles (NPs) of a similar size, uniformly distributed over the surface of a carbon support, were obtained by the original method of liquid-phase synthesis. A comparative study of the structural characteristics, catalytic activity in the oxygen electroreduction reaction (ORR), and durability of the synthesized catalysts, as well as their commercial analogs, was carried out. https://www.selleckchem.com/products/azd7545.html It was shown that the uniformity of the structural and morphological characteristics of Pt/C catalysts makes it possible to reduce the negative effect of the small size of NPs on their stability. As a result, the obtained catalysts were significantly superior to their commercial analogs regarding ORR activity, but not inferior to them in terms of stability.In order to effectively utilize the photovoltaic properties of gallium arsenide, its surface/interface needs to be properly prepared. In the experiments described here we examined eight different paths of GaAs surface treatment (cleaning, etching, passivation) which resulted in different external quantum efficiency (EQE) values of the tested photovoltaic (PV) cells. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) examinations were conducted to obtain structural details of the devices. X-ray photoelectron spectroscopy (XPS) with depth profiling was used to examine interface structure and changes in the elemental content and chemical bonds. The photoluminescence (PL) properties and bandgap measurements of the deposited layers were also reported. The highest EQE value was obtained for the samples initially etched with a citric acid-based etchant and, in the last preparation step, either passivated with ammonium sulfide aqueous solution or treated with ammonium hydroxide solution with no final passivation. Subsequent I-V measurements, however, confirmed that from these samples, only the sulfur-passivated ones provided the highest current density. The tested devices were fabricated by using the ALD method.This study aimed to reveal the differences in intestinal microbes in osteoporotic rats. The rats were divided into two groups the control and OP (osteoporosis) groups (n=6). Days 0 and 70 were set as the time points. The rats in the OP group underwent bilateral ovariectomy (OVX). Differences between the control and OP groups were determined by 16S rDNA analysis. The relative abundances of OTUs and alpha/beta diversities were determined at days 0 days and 70. The abundances of Verrucomicrobia at the phylum level and Aerococcus, Coprobacillus, Veillonella, Anaerobiospirillum, Flavobacterium, Comamonadaceae, Ohtaekwangia, etc., at the genus level were found to be different between the control_70d and OP_70d groups. KEGG ontology analysis showed that the function of lipid metabolism could be related to OP. The 16S rDNA analysis in the OP rats revealed that intestinal microbes take part in the processes of OP and could affect lipid metabolism. Further study of the relationship between OP and intestinal microbes is necessary, and the prospect for intestinal microbes is a potential treatment for OP.
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  • A single shot large-capacity optical multiple-image encryption method based on wavelength multiplexing and position multiplexing is proposed. In the encryption process of the proposed method, multiple plane waves of different wavelengths are adopted to illuminate secret images that are placed at different positions along the optical axis. All the secret images are encoded into a single grayscale intensity-only image that is recorded by a monochromic camera by applying a diffractive-imaging based double random phase encoding (DRPE) system. In the decryption process, high accuracy images are decrypted without crosstalk from the intensity image through a multimode phase retrieval algorithm and a two-step iterative shrinkage/thresholding (TwIST) algorithm. The feasibility of the proposed method is demonstrated by numerical simulations.We present an optical architecture for a scanning lidar in which a digital micromirror device (DMD) is placed at an intermediate image plane in a receiver to decouple the trade-offs between scan angle, scan speed, and aperture size of the lidar's transmitter and receiver. https://www.selleckchem.com/products/iu1.html In the architecture, the transmitter with a galvo mirror and the receiver with a DMD scan the horizontal and vertical fields of view, respectively, to enable an increased field of view of 50°, centimeter transmitter beam diameter, and video frame rate range finding captures. We present our optimized system and discuss the adjustable parameter trade-offs.A novel Rayleigh noise suppression method is proposed to improve temperature accuracy and resolution for Raman distributed fiber-optics sensors. The proposed temperature demodulation method can eliminate temperature measurement inaccuracy caused by Rayleigh noise. The experimental results indicate that the temperature accuracy is optimized from 6.2°C to 1.7°C at a sensing distance of 9.1 km by using the proposed method, and the temperature resolution leads to about 1.5°C improvement compared with the tradition demodulation method at a sensing distance of 10.0 km. The proposed method provides a robust and reliable high performance for long sensing ranges.A high-precision microdisplacement sensor based on zeroth-order diffraction of a single-layer optical grating is reported. Laser grating interference occurs when part of the laser is reflected diffraction by the grating and another part is vertically reflected **** by a mirror and diffracted again by the grating, thus generating optical interferometric detection. For the purpose of obtaining the optimal contrast of the optical interferometric detection, the duty cycle of the grating and the orders of diffraction were optimized by the diffraction scalar theory. The microdisplacement sensor demonstrates a sensitivity of 0.40%/nm, a resolution of 0.6 nm, and a full-scale range of up to 100 µm. This work enables a high-performance displacement sensor, and provides a theoretical and technical basis for the design of a displacement sensor with an ultracompact structure.A bidirectional tuning mechanism of whispering gallery modes (WGMs) in a capillary-based microbubble microresonator infiltrated with magnetic fluids (MFs) is investigated. Owing to distinct RI responses of MFs dependent on the applied magnetic field direction with respect to the capillary axis, the RI of MFs shows different variation trends when an external magnetic field is parallel or perpendicular to the capillary axis. Experimental results indicate that WGM resonance dips exhibit wavelength shift in inverse directions for the above two cases, which is in accordance with our theoretical analysis on different refractive variation behaviors of MFs. As the applied magnetic field is perpendicular or parallel to the capillary axis, the WGM resonance wavelength tuning sensitivities tend to be $ - 15.01\;\rm pm/mT$-15.01pm/mT and 6.3 pm/mT, respectively. Our proposed WGM tuning scheme has several desirable advantages, including bidirectional tunability, high Q-factor, ease of fabrication, and good compatibility with functional materials, making it a promising candidate in the field of magnetic field vector sensing and magnetically manipulated micro-optic devices.In this paper, we propose and demonstrate ultrafast Te nanorods as a saturable absorber (SA) for producing mode locking from an erbium-doped fiber laser for the first time, to the best of our knowledge. The Te nanorods were fabricated by a simple green chemical method with energy conservation and without a purification process. The morphology and structure measurements confirm uniform Te nanorods with a constant aspect ratio. The synthesized SA has a saturation intensity and modulation depth of $25.44\, \rm MW/cm^2 $25.44MW/cm2 and 4%, respectively. By integrating the proposed SA into an erbium-doped all fiber-based ring cavity, the mode-locked fiber laser was readily generated. The conventional soliton pulses of $3.56\;\rm ps$3.56ps pulse width were obtained at 1566.7 nm central wavelength and a pulse repetition rate of 1.87 MHz. The results show that the moderate saturable-absorption characteristics of Te nanorods have superior performance in the ultrafast optics field, which is eligible in many applications, such as optical communications.In this paper, we put forward a new application in optical data storage (ODS) of tetraphenylethene (TPE)-doped photopolymer, which has an aggregation-induced emission attribute. The photopolymer host reacted with the excitation light at the focal point of a high numerical-aperture lens to enhance the fluorescence intensity mainly because of the function of the $\rm Zn^2 + $Zn2+ ion. We recorded data inside the photopolymer matrix by using this property and had distinct fluorescence intensity contrast between the photochemical regions and other regions. This attribute paves a new way for superresolution ODS and opens the way to exploring the possibility of utilizing TPE-doped photopolymers as chemical sensors in the future.Analysis of spatial frequency of Mueller matrix (MM) images in the Fourier domain yields quantifying parameters of anisotropy in the stromal region in normal and precancerous tissue sections of human uterine cervix. The spatial frequencies of MM elements reveal reliable information of microscopic structural organization arising from the different orientations of collagen fibers in the connective tissue and their randomization with disease progression. Specifically, the local disorder generated in the normal periodic and regular structure of collagen during the growth of the cervical cancer finds characteristic manifestation in the Fourier spectrum of the selected Mueller matrix elements encoding the anisotropy effects through retardance and birefringence. In contrast, Fourier spectra of differential polarization gated images are limited to only one orientation of collagen. Fourier spectra of first row elements M11, M12, M13, and M14 and first column elements M11, M21, M31, and M41 discriminates cervical inter-epithelial neoplasia (CIN)-I from normal cervical tissue samples with 95%-100% sensitivity and specificity.
    A single shot large-capacity optical multiple-image encryption method based on wavelength multiplexing and position multiplexing is proposed. In the encryption process of the proposed method, multiple plane waves of different wavelengths are adopted to illuminate secret images that are placed at different positions along the optical axis. All the secret images are encoded into a single grayscale intensity-only image that is recorded by a monochromic camera by applying a diffractive-imaging based double random phase encoding (DRPE) system. In the decryption process, high accuracy images are decrypted without crosstalk from the intensity image through a multimode phase retrieval algorithm and a two-step iterative shrinkage/thresholding (TwIST) algorithm. The feasibility of the proposed method is demonstrated by numerical simulations.We present an optical architecture for a scanning lidar in which a digital micromirror device (DMD) is placed at an intermediate image plane in a receiver to decouple the trade-offs between scan angle, scan speed, and aperture size of the lidar's transmitter and receiver. https://www.selleckchem.com/products/iu1.html In the architecture, the transmitter with a galvo mirror and the receiver with a DMD scan the horizontal and vertical fields of view, respectively, to enable an increased field of view of 50°, centimeter transmitter beam diameter, and video frame rate range finding captures. We present our optimized system and discuss the adjustable parameter trade-offs.A novel Rayleigh noise suppression method is proposed to improve temperature accuracy and resolution for Raman distributed fiber-optics sensors. The proposed temperature demodulation method can eliminate temperature measurement inaccuracy caused by Rayleigh noise. The experimental results indicate that the temperature accuracy is optimized from 6.2°C to 1.7°C at a sensing distance of 9.1 km by using the proposed method, and the temperature resolution leads to about 1.5°C improvement compared with the tradition demodulation method at a sensing distance of 10.0 km. The proposed method provides a robust and reliable high performance for long sensing ranges.A high-precision microdisplacement sensor based on zeroth-order diffraction of a single-layer optical grating is reported. Laser grating interference occurs when part of the laser is reflected diffraction by the grating and another part is vertically reflected back by a mirror and diffracted again by the grating, thus generating optical interferometric detection. For the purpose of obtaining the optimal contrast of the optical interferometric detection, the duty cycle of the grating and the orders of diffraction were optimized by the diffraction scalar theory. The microdisplacement sensor demonstrates a sensitivity of 0.40%/nm, a resolution of 0.6 nm, and a full-scale range of up to 100 µm. This work enables a high-performance displacement sensor, and provides a theoretical and technical basis for the design of a displacement sensor with an ultracompact structure.A bidirectional tuning mechanism of whispering gallery modes (WGMs) in a capillary-based microbubble microresonator infiltrated with magnetic fluids (MFs) is investigated. Owing to distinct RI responses of MFs dependent on the applied magnetic field direction with respect to the capillary axis, the RI of MFs shows different variation trends when an external magnetic field is parallel or perpendicular to the capillary axis. Experimental results indicate that WGM resonance dips exhibit wavelength shift in inverse directions for the above two cases, which is in accordance with our theoretical analysis on different refractive variation behaviors of MFs. As the applied magnetic field is perpendicular or parallel to the capillary axis, the WGM resonance wavelength tuning sensitivities tend to be $ - 15.01\;\rm pm/mT$-15.01pm/mT and 6.3 pm/mT, respectively. Our proposed WGM tuning scheme has several desirable advantages, including bidirectional tunability, high Q-factor, ease of fabrication, and good compatibility with functional materials, making it a promising candidate in the field of magnetic field vector sensing and magnetically manipulated micro-optic devices.In this paper, we propose and demonstrate ultrafast Te nanorods as a saturable absorber (SA) for producing mode locking from an erbium-doped fiber laser for the first time, to the best of our knowledge. The Te nanorods were fabricated by a simple green chemical method with energy conservation and without a purification process. The morphology and structure measurements confirm uniform Te nanorods with a constant aspect ratio. The synthesized SA has a saturation intensity and modulation depth of $25.44\, \rm MW/cm^2 $25.44MW/cm2 and 4%, respectively. By integrating the proposed SA into an erbium-doped all fiber-based ring cavity, the mode-locked fiber laser was readily generated. The conventional soliton pulses of $3.56\;\rm ps$3.56ps pulse width were obtained at 1566.7 nm central wavelength and a pulse repetition rate of 1.87 MHz. The results show that the moderate saturable-absorption characteristics of Te nanorods have superior performance in the ultrafast optics field, which is eligible in many applications, such as optical communications.In this paper, we put forward a new application in optical data storage (ODS) of tetraphenylethene (TPE)-doped photopolymer, which has an aggregation-induced emission attribute. The photopolymer host reacted with the excitation light at the focal point of a high numerical-aperture lens to enhance the fluorescence intensity mainly because of the function of the $\rm Zn^2 + $Zn2+ ion. We recorded data inside the photopolymer matrix by using this property and had distinct fluorescence intensity contrast between the photochemical regions and other regions. This attribute paves a new way for superresolution ODS and opens the way to exploring the possibility of utilizing TPE-doped photopolymers as chemical sensors in the future.Analysis of spatial frequency of Mueller matrix (MM) images in the Fourier domain yields quantifying parameters of anisotropy in the stromal region in normal and precancerous tissue sections of human uterine cervix. The spatial frequencies of MM elements reveal reliable information of microscopic structural organization arising from the different orientations of collagen fibers in the connective tissue and their randomization with disease progression. Specifically, the local disorder generated in the normal periodic and regular structure of collagen during the growth of the cervical cancer finds characteristic manifestation in the Fourier spectrum of the selected Mueller matrix elements encoding the anisotropy effects through retardance and birefringence. In contrast, Fourier spectra of differential polarization gated images are limited to only one orientation of collagen. Fourier spectra of first row elements M11, M12, M13, and M14 and first column elements M11, M21, M31, and M41 discriminates cervical inter-epithelial neoplasia (CIN)-I from normal cervical tissue samples with 95%-100% sensitivity and specificity.
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  • Bioimaging and biosensing have garnered interest in early cancer diagnosis due to the ability of gaining in-depth insights into cellular functions and providing a wide range of diagnostic parameters. Emerging 2D materials of multielement MXenes and monoelement black phosphorous nanosheets (BPNSs) with unique intrinsic physicochemical properties such as a tunable bandgap and layer-dependent fluorescence, high carrier mobility and transport anisotropy, efficient fluorescence quenching capability, desirable light absorption and thermoelastic properties, and excellent biocompatibility and biosafety properties provide promising nano-platforms for bioimaging and biosensing applications. In view of the growing attention on the rising stars of the post-graphene age in the progress of bioimaging and biosensing, and their common feature characteristics as well as complementarity for constructing complexes, the main objective of this review is to reveal the recent advances in the design of MXene or BPNS based nanoplatforms in the field of bioimaging and biosensing. The preparation and surface functionalization methods, biosafety, and other important aspects of bioimaging and biosensing applications of MXenes and BPNSs have been assessed systematically, along with highlighting the main challenges in further biomedical application. The review not only focuses on the advancements in 2D materials for use in bioimaging and biosensing but also assesses the possibility of their future potential in bioapplications.In order to raise the possibility of the practical use of thermoresponsive hydrogels in various fields, it is imperative to achieve on-demand control of responsive behavior especially by using a simple synthetic method with common monomers. To this end, we synthesized various hydrophilic/hydrophobic copolymer hydrogels from common acrylamide derivatives and acrylate monomers via free radical copolymerization, and examined the correlation between the structure and the swelling properties of the obtained gels, specifically from the viewpoint of the monomer sequence in the network chains and the affinity to water molecules. The obtained gels with a hydrophobic acrylamide monomer were shown to exhibit a sharp volume change in water upon heating at suitable monomer compositions. In contrast, the gels consisting of a hydrophobic acrylate monomer only decreased the swelling degree with no significant thermoresponsive volume change. The formation of a local amphiphilic structure without a long hydrophobic sequence is critical for achieving sharp thermoresponsiveness. Moreover, the water affinity was drastically changed at a sharp volume transition with the copolymer gels of a hydrophobic acrylamide. This transition was most likely driven by an entropic factor because of the strong contribution of the hydration/dehydration of the network chains. The comparison of the temperature-responsive behavior of the gels with that of the corresponding linear copolymers demonstrated that the crosslinking structure made significant hydrophobic contribution to the responsive behavior.Multidrug-resistant bacterial infections are a grand challenge to global medical and health systems. Therefore, it is urgent to develop versatile antibacterial strategies that can combat bacterial resistance without displaying toxicity. Here, we synthesize antibacterial polypeptide-conjugated gold nanoparticles that exhibit potent antibacterial activities against clinically isolated multiple drug resistance Gram-positive bacteria, such as methicillin-resistant Staphylococcus aureus, and excellent in vitro and in vivo biocompatibility. https://www.selleckchem.com/peptide/bulevirtide-myrcludex-b.html The antibacterial mechanism study indicates that over-production of reactive oxygen species results in the killing of bacteria. The overall antibacterial performance of these polypeptide-conjugated gold nanoparticles and the convenient synthesis of these polypeptides via lithium hexamethyldisilazide-initiated fast ring-opening polymerization on α-amino acid N-carboxyanhydride imply the potential application of this strategy in treating bacterial infections.Cancer vaccines are made from tumor-specific antigens, which are then injected **** into the body to activate immune responses for cancer immunotherapy. Despite the high specificity and therapeutic efficiency, the vaccine has huge challenges such as complex preparation process, expensiveness and limited durational effects. Herein, a strategy to develop in situ cancer vaccines by enhancing the immunomodulatory effects for immunogenic cell death (ICD) is presented. First, amorphous iron oxide-packaged oxaliplatin (AIOoxp) nanoprodrugs with a high drug loading efficiency of 12.9% were prepared. By utilizing tumor microenvironment (TME) as an endogenous stimulus, this inorganic nanoprodrug can effectively realize TME-responsive combined treatments of chemotherapy and chemodynamic therapy (CDT), and thus achieve dual and precise ICD induction. Further, in vivo immunopotentiation performances further prove that this enhanced ICD effect is able to efficiently promote the maturity of dendritic cells (DCs), T cell activation and correlative cytokine secretion. Furthermore, the obtained nanoprodrugs not only reduce systemic toxicities of Oxp and achieve T1/T2 magnetic resonance imaging (MRI), but also dramatically inhibit tumor growth and lung metastasis. We believe that the design of in situ cancer vaccines by enhancing the ICD effects will inspire future studies on cancer vaccines.Breast cancer is the most prevalent malignant disease among women across the globe. Notably, estrogen signaling plays a vital role in the progression of estrogen receptor-positive breast cancer. Therefore, targeting epigenetic regulators is a promising therapy for cancer. To identify epigenetic regulators, we conducted a siRNA screening targeting 140 epigenetic genes by which 32 positive and 15 negative regulators of estrogen signaling were obtained. The protein-protein interaction network of the candidate genes was constructed and the topological parameters of the network were calculated. As a result, the top 10 genes with higher MCC (Maximal Clique Centrality) scores were considered as hub genes. Notably, the hub genes all belong to polycomb group genes. The transcription levels of the above genes were compared between breast cancer and normal tissues using the UALCAN database. Then, the survival analysis of the hub genes was conducted using the Kaplan-Meier Plotter online database. Lastly, the effect of hub genes on MCF-7 cell proliferation and ER target gene expression were investigated.
    Bioimaging and biosensing have garnered interest in early cancer diagnosis due to the ability of gaining in-depth insights into cellular functions and providing a wide range of diagnostic parameters. Emerging 2D materials of multielement MXenes and monoelement black phosphorous nanosheets (BPNSs) with unique intrinsic physicochemical properties such as a tunable bandgap and layer-dependent fluorescence, high carrier mobility and transport anisotropy, efficient fluorescence quenching capability, desirable light absorption and thermoelastic properties, and excellent biocompatibility and biosafety properties provide promising nano-platforms for bioimaging and biosensing applications. In view of the growing attention on the rising stars of the post-graphene age in the progress of bioimaging and biosensing, and their common feature characteristics as well as complementarity for constructing complexes, the main objective of this review is to reveal the recent advances in the design of MXene or BPNS based nanoplatforms in the field of bioimaging and biosensing. The preparation and surface functionalization methods, biosafety, and other important aspects of bioimaging and biosensing applications of MXenes and BPNSs have been assessed systematically, along with highlighting the main challenges in further biomedical application. The review not only focuses on the advancements in 2D materials for use in bioimaging and biosensing but also assesses the possibility of their future potential in bioapplications.In order to raise the possibility of the practical use of thermoresponsive hydrogels in various fields, it is imperative to achieve on-demand control of responsive behavior especially by using a simple synthetic method with common monomers. To this end, we synthesized various hydrophilic/hydrophobic copolymer hydrogels from common acrylamide derivatives and acrylate monomers via free radical copolymerization, and examined the correlation between the structure and the swelling properties of the obtained gels, specifically from the viewpoint of the monomer sequence in the network chains and the affinity to water molecules. The obtained gels with a hydrophobic acrylamide monomer were shown to exhibit a sharp volume change in water upon heating at suitable monomer compositions. In contrast, the gels consisting of a hydrophobic acrylate monomer only decreased the swelling degree with no significant thermoresponsive volume change. The formation of a local amphiphilic structure without a long hydrophobic sequence is critical for achieving sharp thermoresponsiveness. Moreover, the water affinity was drastically changed at a sharp volume transition with the copolymer gels of a hydrophobic acrylamide. This transition was most likely driven by an entropic factor because of the strong contribution of the hydration/dehydration of the network chains. The comparison of the temperature-responsive behavior of the gels with that of the corresponding linear copolymers demonstrated that the crosslinking structure made significant hydrophobic contribution to the responsive behavior.Multidrug-resistant bacterial infections are a grand challenge to global medical and health systems. Therefore, it is urgent to develop versatile antibacterial strategies that can combat bacterial resistance without displaying toxicity. Here, we synthesize antibacterial polypeptide-conjugated gold nanoparticles that exhibit potent antibacterial activities against clinically isolated multiple drug resistance Gram-positive bacteria, such as methicillin-resistant Staphylococcus aureus, and excellent in vitro and in vivo biocompatibility. https://www.selleckchem.com/peptide/bulevirtide-myrcludex-b.html The antibacterial mechanism study indicates that over-production of reactive oxygen species results in the killing of bacteria. The overall antibacterial performance of these polypeptide-conjugated gold nanoparticles and the convenient synthesis of these polypeptides via lithium hexamethyldisilazide-initiated fast ring-opening polymerization on α-amino acid N-carboxyanhydride imply the potential application of this strategy in treating bacterial infections.Cancer vaccines are made from tumor-specific antigens, which are then injected back into the body to activate immune responses for cancer immunotherapy. Despite the high specificity and therapeutic efficiency, the vaccine has huge challenges such as complex preparation process, expensiveness and limited durational effects. Herein, a strategy to develop in situ cancer vaccines by enhancing the immunomodulatory effects for immunogenic cell death (ICD) is presented. First, amorphous iron oxide-packaged oxaliplatin (AIOoxp) nanoprodrugs with a high drug loading efficiency of 12.9% were prepared. By utilizing tumor microenvironment (TME) as an endogenous stimulus, this inorganic nanoprodrug can effectively realize TME-responsive combined treatments of chemotherapy and chemodynamic therapy (CDT), and thus achieve dual and precise ICD induction. Further, in vivo immunopotentiation performances further prove that this enhanced ICD effect is able to efficiently promote the maturity of dendritic cells (DCs), T cell activation and correlative cytokine secretion. Furthermore, the obtained nanoprodrugs not only reduce systemic toxicities of Oxp and achieve T1/T2 magnetic resonance imaging (MRI), but also dramatically inhibit tumor growth and lung metastasis. We believe that the design of in situ cancer vaccines by enhancing the ICD effects will inspire future studies on cancer vaccines.Breast cancer is the most prevalent malignant disease among women across the globe. Notably, estrogen signaling plays a vital role in the progression of estrogen receptor-positive breast cancer. Therefore, targeting epigenetic regulators is a promising therapy for cancer. To identify epigenetic regulators, we conducted a siRNA screening targeting 140 epigenetic genes by which 32 positive and 15 negative regulators of estrogen signaling were obtained. The protein-protein interaction network of the candidate genes was constructed and the topological parameters of the network were calculated. As a result, the top 10 genes with higher MCC (Maximal Clique Centrality) scores were considered as hub genes. Notably, the hub genes all belong to polycomb group genes. The transcription levels of the above genes were compared between breast cancer and normal tissues using the UALCAN database. Then, the survival analysis of the hub genes was conducted using the Kaplan-Meier Plotter online database. Lastly, the effect of hub genes on MCF-7 cell proliferation and ER target gene expression were investigated.
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  • The treatment was eventually considered a failure after 6-month duration and one patient needed MVD for pain control. Post-GKRS pain control remains inferior in patients with dolichoectasia compared with typical TGN. GKRS should be offered only as a salvage or rescue procedure and should not be used as an alternative treatment of MVD in patient population with dolichoectatic vessels.[This corrects the article DOI 10.1007/s13193-021-01278-9.].Pancreaticoduodenectomy (PD) is a common surgery performed with curative intent for periampullary and pancreatic head neoplasms. In the presence of intrinsic celiac artery narrowing due to atherosclerosis or extrinsic compression due to median arcuate ligament syndrome (MALS), division of the gastroduodenal artery during PD can result in liver ischemia. This report describes a patient who had MALS which was treated by intraoperative median arcuate ligament release during PD, resulting in restoration of hepatic artery pulsations. Preventive, management strategies for MALS and the communicating vascular arcades between the celiac and superior mesenteric arterial systems are discussed in the context of PD.Adenoid cystic carcinoma of the nasopharynx is a rare, slow growing, and locally aggressive neoplasm. Three cases presented with recurrent epistaxis. Endoscopy-guided biopsy proved the diagnosis of adenoid cystic carcinoma. The location and the extent of the tumor were confirmed on imaging. Surgery followed by radiation therapy was the treatment modality used. All three cases showed good clinical response. The aim is to discuss the surgical approach and review of literature concerning this malignancy.Metastatic breast cancer is not a curable disease, but women with metastatic disease are living longer. Although the relative survival has improved in recent years still patients who present with metastatic disease have a less than 30% 5-year survival. Historically, removal of the primary breast tumor has been offered to these patients only for palliation. However, there have been recent reports that removal of the primary tumor may improve survival. These are mostly retrospective studies limited by selection bias. Prospective and randomized trials have not shown a clear survival advantage. Although the definitive role of removal of the primary tumor in metastatic breast cancer is not settled, it is critical to understand the complexities of this debate in order to make further gains in breast cancer survivorship.5-Aminolevulinic acid (ALA)-induced fluorescence cystoscopy has established itself in the detection of flat and/or small lesions. This is explained by the simple fact that there is increased uptake of ALA, altered activity of certain enzymes, and altered intracellular redistribution and storage of protoporphyrin IX (PPIX) in the malignant cells. Intracellular PPIX allows red fluorescence detection. In this preliminary study, the efficacy of 5-ALA-induced fluorescent urine cytology was compared with conventional cytology in the diagnosis of bladder tumours. In this prospective study, patients ≥18 years of age admitted to the department of urology with non-malignant conditions formed the controls and patients ≥18 years of age with imaging confirmed bladder tumours formed the study group. Freshly voided urine sample was collected from these patients and divided into two samples of 50 cc each. One of these samples was sent in for conventional cytology examination, whereas the other sample was sent in for 5-ALA fluorescent photo dynamic diagnosis. Conventional cytology and 5-ALA-induced fluorescent cytology were evaluated by the same pathologist. A total of 100 patients were included in the study of which 75 patients were controls and the remaining 25 were patients with bladder tumours. The sensitivity of conventional cytology and 5-ALA-induced fluorescent cytology was 64% and 100% respectively, whereas the specificity was 96% and 98.67% respectively. The sensitivity of conventional cytology was 61.19% in low-grade cancers as compared to 75% in high-grade cancers, whereas the sensitivity was 100% with 5-ALA-induced fluorescent cytology both in low- as well as high-grade cancers. Our study shows that 5-ALA-induced fluorescent cytology is highly sensitive test to diagnose bladder cancer and shows a significant difference especially in low-grade bladder cancer when compared to conventional cytology.In oral squamous cell carcinoma (OSCC), expression of PDL1 is controversial with expressions showing a positive and negative correlation with survival in previous studies. Additionally, it is unclear whether expression on the tumour or tumour infiltrating lymphocytes (TIL) is a better predictor of survival. We performed this study on a cohort of Indian patients with OSCC to determine impact of PDL1 expression on survival. Retrospective analysis of 64 patients of OSCC treated with curative intent surgery with or without adjuvant therapy was performed. Stored tissue blocks were extracted and quantitative immunohistochemistry was performed for PDL1 expression separately on the tumour and the TIL using commercially available Dako kits. Correlation of clinical and pathological variables with PDL1 expression was performed using chi-square test. Survival analysis was performed using Kaplan-Meier method and Cox proportional hazards ratio. In our cohort, PDL1 expression was low, both in tumour (92% had less then 1% expression) and TIL (56% had less then 1% expression). Tumour low PDL1 expression ( less then 1%) was associated with a higher risk of lymphovascular invasion (p = 0.044) and bone invasion (p = 0.01) but did not impact survival. Low TIL PDL1 expression ( less then 1%) was more common in younger patients ( less then 45 years) (p = 0.023) significantly predicting local recurrence (p = 0.02). PDL1 expression in OSCC was low. Low TIL PDL1 was common in younger patients and predicted local recurrence. Further study is required to better understand the relationship between age, tumour microenvironment and local recurrence.Surgical management of breast cancer (**) has evolved from radical surgeries to conservative with better cosmetic and comparable oncological outcomes. For axillary staging, it has evolved from axillary lymph node dissection (ALND) to sentinel lymph node biopsy (SLNB). No detailed information exists in terms of the clinical practice pattern of surgical management of axilla for ** patients in India. A questionnaire-based survey was developed. The survey was done at the annual meeting of the Association of Breast Surgeons of India (ABSI) in November 2018. Responses were recorded and analysed by SPSS 23. One hundred twelve out of 400 (28%) responded to the survey. Half of the respondents were surgical oncologist and 36.6% were performing > 150 ** surgeries/year. https://www.selleckchem.com/products/ucl-tro-1938.html The primary technique for axillary staging in node-negative ** was SLNB for 68.5% of respondents. Majority of surgeons (47%) reported performing SLNB by methylene blue dye only. Unavailability of radioisotope (46.7%) and lack of frozen section (26.7%) were reported as two major barriers for not performing SLNB.
    The treatment was eventually considered a failure after 6-month duration and one patient needed MVD for pain control. Post-GKRS pain control remains inferior in patients with dolichoectasia compared with typical TGN. GKRS should be offered only as a salvage or rescue procedure and should not be used as an alternative treatment of MVD in patient population with dolichoectatic vessels.[This corrects the article DOI 10.1007/s13193-021-01278-9.].Pancreaticoduodenectomy (PD) is a common surgery performed with curative intent for periampullary and pancreatic head neoplasms. In the presence of intrinsic celiac artery narrowing due to atherosclerosis or extrinsic compression due to median arcuate ligament syndrome (MALS), division of the gastroduodenal artery during PD can result in liver ischemia. This report describes a patient who had MALS which was treated by intraoperative median arcuate ligament release during PD, resulting in restoration of hepatic artery pulsations. Preventive, management strategies for MALS and the communicating vascular arcades between the celiac and superior mesenteric arterial systems are discussed in the context of PD.Adenoid cystic carcinoma of the nasopharynx is a rare, slow growing, and locally aggressive neoplasm. Three cases presented with recurrent epistaxis. Endoscopy-guided biopsy proved the diagnosis of adenoid cystic carcinoma. The location and the extent of the tumor were confirmed on imaging. Surgery followed by radiation therapy was the treatment modality used. All three cases showed good clinical response. The aim is to discuss the surgical approach and review of literature concerning this malignancy.Metastatic breast cancer is not a curable disease, but women with metastatic disease are living longer. Although the relative survival has improved in recent years still patients who present with metastatic disease have a less than 30% 5-year survival. Historically, removal of the primary breast tumor has been offered to these patients only for palliation. However, there have been recent reports that removal of the primary tumor may improve survival. These are mostly retrospective studies limited by selection bias. Prospective and randomized trials have not shown a clear survival advantage. Although the definitive role of removal of the primary tumor in metastatic breast cancer is not settled, it is critical to understand the complexities of this debate in order to make further gains in breast cancer survivorship.5-Aminolevulinic acid (ALA)-induced fluorescence cystoscopy has established itself in the detection of flat and/or small lesions. This is explained by the simple fact that there is increased uptake of ALA, altered activity of certain enzymes, and altered intracellular redistribution and storage of protoporphyrin IX (PPIX) in the malignant cells. Intracellular PPIX allows red fluorescence detection. In this preliminary study, the efficacy of 5-ALA-induced fluorescent urine cytology was compared with conventional cytology in the diagnosis of bladder tumours. In this prospective study, patients ≥18 years of age admitted to the department of urology with non-malignant conditions formed the controls and patients ≥18 years of age with imaging confirmed bladder tumours formed the study group. Freshly voided urine sample was collected from these patients and divided into two samples of 50 cc each. One of these samples was sent in for conventional cytology examination, whereas the other sample was sent in for 5-ALA fluorescent photo dynamic diagnosis. Conventional cytology and 5-ALA-induced fluorescent cytology were evaluated by the same pathologist. A total of 100 patients were included in the study of which 75 patients were controls and the remaining 25 were patients with bladder tumours. The sensitivity of conventional cytology and 5-ALA-induced fluorescent cytology was 64% and 100% respectively, whereas the specificity was 96% and 98.67% respectively. The sensitivity of conventional cytology was 61.19% in low-grade cancers as compared to 75% in high-grade cancers, whereas the sensitivity was 100% with 5-ALA-induced fluorescent cytology both in low- as well as high-grade cancers. Our study shows that 5-ALA-induced fluorescent cytology is highly sensitive test to diagnose bladder cancer and shows a significant difference especially in low-grade bladder cancer when compared to conventional cytology.In oral squamous cell carcinoma (OSCC), expression of PDL1 is controversial with expressions showing a positive and negative correlation with survival in previous studies. Additionally, it is unclear whether expression on the tumour or tumour infiltrating lymphocytes (TIL) is a better predictor of survival. We performed this study on a cohort of Indian patients with OSCC to determine impact of PDL1 expression on survival. Retrospective analysis of 64 patients of OSCC treated with curative intent surgery with or without adjuvant therapy was performed. Stored tissue blocks were extracted and quantitative immunohistochemistry was performed for PDL1 expression separately on the tumour and the TIL using commercially available Dako kits. Correlation of clinical and pathological variables with PDL1 expression was performed using chi-square test. Survival analysis was performed using Kaplan-Meier method and Cox proportional hazards ratio. In our cohort, PDL1 expression was low, both in tumour (92% had less then 1% expression) and TIL (56% had less then 1% expression). Tumour low PDL1 expression ( less then 1%) was associated with a higher risk of lymphovascular invasion (p = 0.044) and bone invasion (p = 0.01) but did not impact survival. Low TIL PDL1 expression ( less then 1%) was more common in younger patients ( less then 45 years) (p = 0.023) significantly predicting local recurrence (p = 0.02). PDL1 expression in OSCC was low. Low TIL PDL1 was common in younger patients and predicted local recurrence. Further study is required to better understand the relationship between age, tumour microenvironment and local recurrence.Surgical management of breast cancer (BC) has evolved from radical surgeries to conservative with better cosmetic and comparable oncological outcomes. For axillary staging, it has evolved from axillary lymph node dissection (ALND) to sentinel lymph node biopsy (SLNB). No detailed information exists in terms of the clinical practice pattern of surgical management of axilla for BC patients in India. A questionnaire-based survey was developed. The survey was done at the annual meeting of the Association of Breast Surgeons of India (ABSI) in November 2018. Responses were recorded and analysed by SPSS 23. One hundred twelve out of 400 (28%) responded to the survey. Half of the respondents were surgical oncologist and 36.6% were performing > 150 BC surgeries/year. https://www.selleckchem.com/products/ucl-tro-1938.html The primary technique for axillary staging in node-negative BC was SLNB for 68.5% of respondents. Majority of surgeons (47%) reported performing SLNB by methylene blue dye only. Unavailability of radioisotope (46.7%) and lack of frozen section (26.7%) were reported as two major barriers for not performing SLNB.
    0 Comments 0 Shares 36 Views 0 Reviews

  • 5; 95% CI 1.4-1.6,
    < .001) independent of race, insurance, receptor status, and stage.

    This study demonstrates significant associations with refusal of breast cancer treatment and quantifies the impact on mortality, which may help to identify at-risk groups for whom interventions could prevent increases in mortality associated with declining treatment.
    This study demonstrates significant associations with refusal of breast cancer treatment and quantifies the impact on mortality, which may help to identify at-risk groups for whom interventions could prevent increases in mortality associated with declining treatment.The C-reactive protein to albumin ratio (CAR) is a predictive marker of systemic inflammatory state in atherosclerotic coronary disease when compared with the predictive value of these 2 markers separately. We investigated the relationship between CAR and infarct-related artery (IRA) patency in patients with ST-segment elevation myocardial infarction (STEMI). The study population (n = 1047) was divided into 2 groups according to IRA patency which was assessed by the Thrombolysis in Myocardial Infarction (TIMI) flow grade. Nonpatent flow was defined as TIMI grade 0 (no-reflow), 1, and 2 flows, and normal flow was defined as TIMI 3 flow. There was a significant positive correlation between CAR and SYNTAX score (r = 0.312, P less then .001) and a negative correlation between CAR and TIMI grade flow (r = -0.210, P less then .001). At a cutoff level of 0.693, the CAR predicted TIMI no-reflow with a sensitivity of 65.4% and a specificity of 65.5% (area under the curve 0.670, 95% CI 0.62-0.71, P less then .001). Multivariate logistic regression analyses showed that CAR was an independent predictor of IRA patency (0.003 [0.001-0.029]; P less then .001). A higher CAR is a significant and independent predictor of IRA patency in patients with STEMI.
    Physical activity (PA) is a therapeutic approach to address post-secondary student mental health, yet the effect of PA on occupational outcomes has been understudied among students.

    This study (1) identified and described occupational performance issues (OPIs) among post-secondary students seeking mental health support and (2) assessed pre- and post-intervention differences in occupational performance and performance satisfaction.

    Using a single group pre-test post-test pilot study design, participants (
    = 20) completed a 6-week, 1-hour PA intervention. The Canadian Occupational Performance Measure was administered pre- and post-intervention.

    The most commonly reported OPIs included academics, PA, and sleep hygiene. There were significant improvements in participants' occupational performance (mean change 2.7,
    < .001;
    = 2.28) and performance satisfaction (mean change 3.7,
    < .001;
    = 3.04).

    Results provide an initial demonstration of the benefits of PA for occupational outcomes within a post-secondary mental health context.
    Results provide an initial demonstration of the benefits of PA for occupational outcomes within a post-secondary mental health context.ATP-binding cassette class A3 (ABCA3) is a lipid transporter that plays a critical role in pulmonary surfactant function. The substitution of valine for glutamic acid at codon 292 (E292V) produces a hypomorphic variant that accounts for a significant portion of ABCA3 mutations associated with lung disorders spanning from neonatal respiratory distress syndrome and childhood interstitial lung disease to diffuse parenchymal lung disease (DPLD) in adults including pulmonary fibrosis. The mechanisms by which this and similar ABCA3 mutations disrupt alveolar type 2 (AT2) cell homeostasis and cause DPLD are largely unclear. The present study, informed by a patient homozygous for the E292V variant, used an in vitro and a preclinical murine model to evaluate the mechanisms by which E292V expression promotes aberrant lung injury and parenchymal remodeling. Cell lines stably expressing enhanced green fluorescent protein (EGFP)-tagged ABCA3 isoforms show a functional deficiency of the ABCA3E292V variant as a lipid transporter. AT2 cells isolated from **** constitutively homozygous for ABCA3E292V demonstrate the presence of small electron-dense lamellar bodies, time-dependent alterations in macroautophagy, and induction of apoptosis. These changes in AT2 cell homeostasis are accompanied by a spontaneous lung phenotype consisting of both age-dependent inflammation and fibrillary collagen deposition in alveolar septa. Older ABCA3E292V **** exhibit increased vulnerability to exogenous lung injury by bleomycin. Collectively, these findings support the hypothesis that the ABCA3E292V variant is a susceptibility factor for lung injury through effects on surfactant deficiency and impaired AT2 cell autophagy.Single-cell transcriptomics analyses of the fibrotic lung uncovered two cell states critical to lung injury recovery in the alveolar epithelium- a reparative transitional cell state in the mouse and a disease-specific cell state (KRT5-/KRT17+) in human idiopathic pulmonary fibrosis (IPF). https://www.selleckchem.com/products/piperlongumine.html The murine transitional cell state lies between the differentiation from type 2 (AT2) to type 1 pneumocyte (AT1), and the human KRT5-/KRT17+cell state may arise from the dysregulation of this differentiation process. We review major findings of single-cell transcriptomics analyses of the fibrotic lung and re-analyzed data from 7 single-cell RNA sequencing studies of human and murine models of IPF, focusing on the alveolar epithelium. Our comparative and cross-species single-cell transcriptomics analyses allowed us to further delineate the differentiation trajectories from AT2 to AT1 and AT2 to the KRT5-/KRT17+cell state. We observed AT1 cells in human IPF retain the transcriptional signature of the murine transitional cell state. Using pseudotime analysis, we recapitulated the differentiation trajectories from AT2 to AT1 and from AT2 to KRT5-/KRT17+ cell state in multiple human IPF studies. We further delineated transcriptional programs underlying cell state transitions and determined the molecular phenotypes at terminal differentiation. We hypothesize that in addition to the reactivation of developmental programs (SOX4, SOX9), senescence (TP63, SOX4) and the Notch pathway (HES1) are predicted to steer intermediate progenitors to the KRT5-/KRT17+cell state. Our analyses suggest that activation of SMAD3 later in the differentiation process may explain the fibrotic molecular phenotype typical of KRT5-/KRT17+cells.
    5; 95% CI 1.4-1.6, < .001) independent of race, insurance, receptor status, and stage. This study demonstrates significant associations with refusal of breast cancer treatment and quantifies the impact on mortality, which may help to identify at-risk groups for whom interventions could prevent increases in mortality associated with declining treatment. This study demonstrates significant associations with refusal of breast cancer treatment and quantifies the impact on mortality, which may help to identify at-risk groups for whom interventions could prevent increases in mortality associated with declining treatment.The C-reactive protein to albumin ratio (CAR) is a predictive marker of systemic inflammatory state in atherosclerotic coronary disease when compared with the predictive value of these 2 markers separately. We investigated the relationship between CAR and infarct-related artery (IRA) patency in patients with ST-segment elevation myocardial infarction (STEMI). The study population (n = 1047) was divided into 2 groups according to IRA patency which was assessed by the Thrombolysis in Myocardial Infarction (TIMI) flow grade. Nonpatent flow was defined as TIMI grade 0 (no-reflow), 1, and 2 flows, and normal flow was defined as TIMI 3 flow. There was a significant positive correlation between CAR and SYNTAX score (r = 0.312, P less then .001) and a negative correlation between CAR and TIMI grade flow (r = -0.210, P less then .001). At a cutoff level of 0.693, the CAR predicted TIMI no-reflow with a sensitivity of 65.4% and a specificity of 65.5% (area under the curve 0.670, 95% CI 0.62-0.71, P less then .001). Multivariate logistic regression analyses showed that CAR was an independent predictor of IRA patency (0.003 [0.001-0.029]; P less then .001). A higher CAR is a significant and independent predictor of IRA patency in patients with STEMI. Physical activity (PA) is a therapeutic approach to address post-secondary student mental health, yet the effect of PA on occupational outcomes has been understudied among students. This study (1) identified and described occupational performance issues (OPIs) among post-secondary students seeking mental health support and (2) assessed pre- and post-intervention differences in occupational performance and performance satisfaction. Using a single group pre-test post-test pilot study design, participants ( = 20) completed a 6-week, 1-hour PA intervention. The Canadian Occupational Performance Measure was administered pre- and post-intervention. The most commonly reported OPIs included academics, PA, and sleep hygiene. There were significant improvements in participants' occupational performance (mean change 2.7, < .001; = 2.28) and performance satisfaction (mean change 3.7, < .001; = 3.04). Results provide an initial demonstration of the benefits of PA for occupational outcomes within a post-secondary mental health context. Results provide an initial demonstration of the benefits of PA for occupational outcomes within a post-secondary mental health context.ATP-binding cassette class A3 (ABCA3) is a lipid transporter that plays a critical role in pulmonary surfactant function. The substitution of valine for glutamic acid at codon 292 (E292V) produces a hypomorphic variant that accounts for a significant portion of ABCA3 mutations associated with lung disorders spanning from neonatal respiratory distress syndrome and childhood interstitial lung disease to diffuse parenchymal lung disease (DPLD) in adults including pulmonary fibrosis. The mechanisms by which this and similar ABCA3 mutations disrupt alveolar type 2 (AT2) cell homeostasis and cause DPLD are largely unclear. The present study, informed by a patient homozygous for the E292V variant, used an in vitro and a preclinical murine model to evaluate the mechanisms by which E292V expression promotes aberrant lung injury and parenchymal remodeling. Cell lines stably expressing enhanced green fluorescent protein (EGFP)-tagged ABCA3 isoforms show a functional deficiency of the ABCA3E292V variant as a lipid transporter. AT2 cells isolated from mice constitutively homozygous for ABCA3E292V demonstrate the presence of small electron-dense lamellar bodies, time-dependent alterations in macroautophagy, and induction of apoptosis. These changes in AT2 cell homeostasis are accompanied by a spontaneous lung phenotype consisting of both age-dependent inflammation and fibrillary collagen deposition in alveolar septa. Older ABCA3E292V mice exhibit increased vulnerability to exogenous lung injury by bleomycin. Collectively, these findings support the hypothesis that the ABCA3E292V variant is a susceptibility factor for lung injury through effects on surfactant deficiency and impaired AT2 cell autophagy.Single-cell transcriptomics analyses of the fibrotic lung uncovered two cell states critical to lung injury recovery in the alveolar epithelium- a reparative transitional cell state in the mouse and a disease-specific cell state (KRT5-/KRT17+) in human idiopathic pulmonary fibrosis (IPF). https://www.selleckchem.com/products/piperlongumine.html The murine transitional cell state lies between the differentiation from type 2 (AT2) to type 1 pneumocyte (AT1), and the human KRT5-/KRT17+cell state may arise from the dysregulation of this differentiation process. We review major findings of single-cell transcriptomics analyses of the fibrotic lung and re-analyzed data from 7 single-cell RNA sequencing studies of human and murine models of IPF, focusing on the alveolar epithelium. Our comparative and cross-species single-cell transcriptomics analyses allowed us to further delineate the differentiation trajectories from AT2 to AT1 and AT2 to the KRT5-/KRT17+cell state. We observed AT1 cells in human IPF retain the transcriptional signature of the murine transitional cell state. Using pseudotime analysis, we recapitulated the differentiation trajectories from AT2 to AT1 and from AT2 to KRT5-/KRT17+ cell state in multiple human IPF studies. We further delineated transcriptional programs underlying cell state transitions and determined the molecular phenotypes at terminal differentiation. We hypothesize that in addition to the reactivation of developmental programs (SOX4, SOX9), senescence (TP63, SOX4) and the Notch pathway (HES1) are predicted to steer intermediate progenitors to the KRT5-/KRT17+cell state. Our analyses suggest that activation of SMAD3 later in the differentiation process may explain the fibrotic molecular phenotype typical of KRT5-/KRT17+cells.
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  • Nonalcoholic fatty liver disease (NAFLD) is considered the most prevalent chronic hepatic disease, as it has been estimated that one of four individuals in the general population has been affected by NAFLD. The evolution of the referred entity, which includes nonalcoholic steatohepatitis (NASH) and hepatic fibrosis, may have crucial and even fatal consequences, leading to cirrhosis and hepatocellular carcinoma. Although NAFLD has also been linked with cardiovascular and renal diseases, and all-cause mortality increment, pharmacological therapy is as yet an unfulfilled demand. Since NAFLD is closely associated with type 2 diabetes mellitus (T2DM), a variety of anti-diabetic drugs have been investigated for their effectiveness towards NAFLD. Sodium-glucose co-transporter 2 inhibitors (SGLT-2i) improve blood glucose levels through increasing renal glucose excretion and they are recommended as one of standard therapeutic categories for T2DM patients. Based on preclinical animal studies, SGLT-2i have shown a beneficial effect on NAFLD, inducing histologically proven amelioration of hepatic steatosis, inflammation and fibrosis. Promising data have been also derived by clinical trials, which have indicated a potentially beneficial effect of SGLT-2i on NAFLD, at least in terms of liver function tests and imaging. Thus, it is not strange that there are many ongoing trials on the effect of various SGLT-2i in NAFLD. https://www.selleckchem.com/peptide/gsmtx4.html In conclusion, current evidence concerning the effect of SGLT-2i on NAFLD is encouraging; however, data from ongoing clinical trials with histological endpoints are awaited.Icariin and icaritin, the major active components of Epimedii Genus, are considered as promising drugs with anti-inflammatory, anti-aging and neuroprotective effects. Our previous studies have demonstrated that icariin and icaritin can protect against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)/1-methyl-4-phenylpyridinium (MPP+)-induced neurotoxicity on dopaminergic neurons via insulin-like growth factor-1 receptor (IGF-1 receptor) signaling. In the present study, we aimed to evaluate the role of IGF-1 receptor signaling in mediating the anti-inflammatory effects of icariin and icaritin against lipopolysaccharide (LPS)-induced neuroinflammation as well as their biological regulation effects in midbrain primary astrocytes. Our results showed that both icariin and icaritin significantly inhibited LPS-induced mRNA expressions of tumor necrosis factor (TNF-α) and interleukin-1β (IL-1β). Pre-treatment with IGF-1 receptor antagonist JB-1 could significantly block the anti-inflammatory effects of icariin and icaritin on LPS-induced up-regulations of TNF-α, IL-1β, cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS). Under basal conditions of astrocytes, icariin and icaritin treatment alone increased the phosphorylation of ERK1/2 and AKT, which could be blocked by JB-1. Moreover, the mRNA expressions of glutamate transptor-1 (GLT-1) and glutamate-aspartate transporter (GLAST) could be up-regulated by icariin and icaritin in a time-dependent manner via IGF-1 receptor. Taken together, our results suggest for the first time that both icariin and icaritin exert regulatory effects in astrocytes under basal conditions and after an inflammatory challenge via IGF-1 receptor signaling pathway.Dengue fever is a common arbovirus disease, which has been spread to the entire tropical world. At present, effective drugs for the treatment of dengue fever have not yet appeared, and the dengue vaccines studied in various countries have also experienced severe adverse reactions. Thus it is urgent to find new chemicals against dengue virus. Now we found Sirtuins (SIRTs) were increased during dengue virus infection and tenovin-1, a SIRT1/2 inhibitor, showed an impressive antiviral ability in vitro. In BHK-21 cells, tenovin-1 inhibited the replication of DENV2 with an EC50 at 3.41 ± 1.10 μM, also inhibited other three types of dengue viruses with EC50 at 0.97 ± 1.11 μM, 1.81 ± 1.08 μM, 3.81 ± 1.34 μM respectively. Moreover, the cytopathic effect-induced DENV2 was largely improved by tenovin-1 treatment and the release of progeny viruses was inhibited by tenovin-1 treatment. At the same time, the viral protein level and mRNA level were decreased with tenovin-1 treatment after dengue virus infection. From the drug-addition assay, the tenovin-1 played its antiviral after viral infection, which indicated tenovin-1 was not a microbicide. Apart from its antiviral effect, tenovin-1 inhibited the inflammatory response caused by DENV2, reducing the release of inflammatory factors during viral infection. The antiviral effect of tenovin-1 was abrogated with SIRT agonist or SIRT2 knockdown treatment, which indicated the effect of tenovin-1 was on-target. In conclusion, tenovin-1 was proved to be a promising compound against flavivirus infection through SIRT2, which should be pay more attention for further study.Renal fibrosis is the pathological consequence of progressive chronic kidney disease. Although it has been reported that vitamin D3 exerts antifibrotic effects, the underlying mechanisms remain unclear. This study is aimed at investigating the effects and molecular mechanisms in high-dose vitamin D3 treatment on renal fibrosis. A model of chronic kidney disease was established by 5/6 nephrectomy in rats characterised by high levels of serum creatine, urea nitrogen, and urinary protein. Serum 25-dihydroxyvitamin D3, calcium and parathormone levels were measured to evaluate vitamin D levels. Hematoxylin and eosin, periodic acid Schiff and Mallory's Trichrome staining were used to evaluate histopathological changes in rats. Moreover, the expression of vimentin, collagen I, α-smooth muscle actin and E-cadherin were analyzed at molecular and histopathological levels. Our results showed that exposure to vitamin D3 decreased the levels of serum creatine, urea nitrogen and urine protein and restored the homeostasis of calcium and parathormone. Vitamin D3 also downregulated the expression of vimentin, collagen I and α-smooth muscle actin and attenuated renal fibrosis and epithelial to mesenchymal transition in the kidney. Importantly, vitamin D3 treatment increased the expression of the vitamin D receptor and inhibited Transforming growth factor-β1 (TGF-β1)/Smad3 signaling pathway in rats kidneys with chronic kidney disease. Mechanistically, the upregulation of TGF-β1 and phosphorylation of Smad3 induced by vitamin D3 was reversed by activation of the vitamin D receptor. Our findings indicated that vitamin D3 is a potential antifibrotic drug in chronic kidney disease via the vitmin D receptor and inhibiting TGF-β1/Smad3 signaling pathway.
    Nonalcoholic fatty liver disease (NAFLD) is considered the most prevalent chronic hepatic disease, as it has been estimated that one of four individuals in the general population has been affected by NAFLD. The evolution of the referred entity, which includes nonalcoholic steatohepatitis (NASH) and hepatic fibrosis, may have crucial and even fatal consequences, leading to cirrhosis and hepatocellular carcinoma. Although NAFLD has also been linked with cardiovascular and renal diseases, and all-cause mortality increment, pharmacological therapy is as yet an unfulfilled demand. Since NAFLD is closely associated with type 2 diabetes mellitus (T2DM), a variety of anti-diabetic drugs have been investigated for their effectiveness towards NAFLD. Sodium-glucose co-transporter 2 inhibitors (SGLT-2i) improve blood glucose levels through increasing renal glucose excretion and they are recommended as one of standard therapeutic categories for T2DM patients. Based on preclinical animal studies, SGLT-2i have shown a beneficial effect on NAFLD, inducing histologically proven amelioration of hepatic steatosis, inflammation and fibrosis. Promising data have been also derived by clinical trials, which have indicated a potentially beneficial effect of SGLT-2i on NAFLD, at least in terms of liver function tests and imaging. Thus, it is not strange that there are many ongoing trials on the effect of various SGLT-2i in NAFLD. https://www.selleckchem.com/peptide/gsmtx4.html In conclusion, current evidence concerning the effect of SGLT-2i on NAFLD is encouraging; however, data from ongoing clinical trials with histological endpoints are awaited.Icariin and icaritin, the major active components of Epimedii Genus, are considered as promising drugs with anti-inflammatory, anti-aging and neuroprotective effects. Our previous studies have demonstrated that icariin and icaritin can protect against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)/1-methyl-4-phenylpyridinium (MPP+)-induced neurotoxicity on dopaminergic neurons via insulin-like growth factor-1 receptor (IGF-1 receptor) signaling. In the present study, we aimed to evaluate the role of IGF-1 receptor signaling in mediating the anti-inflammatory effects of icariin and icaritin against lipopolysaccharide (LPS)-induced neuroinflammation as well as their biological regulation effects in midbrain primary astrocytes. Our results showed that both icariin and icaritin significantly inhibited LPS-induced mRNA expressions of tumor necrosis factor (TNF-α) and interleukin-1β (IL-1β). Pre-treatment with IGF-1 receptor antagonist JB-1 could significantly block the anti-inflammatory effects of icariin and icaritin on LPS-induced up-regulations of TNF-α, IL-1β, cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS). Under basal conditions of astrocytes, icariin and icaritin treatment alone increased the phosphorylation of ERK1/2 and AKT, which could be blocked by JB-1. Moreover, the mRNA expressions of glutamate transptor-1 (GLT-1) and glutamate-aspartate transporter (GLAST) could be up-regulated by icariin and icaritin in a time-dependent manner via IGF-1 receptor. Taken together, our results suggest for the first time that both icariin and icaritin exert regulatory effects in astrocytes under basal conditions and after an inflammatory challenge via IGF-1 receptor signaling pathway.Dengue fever is a common arbovirus disease, which has been spread to the entire tropical world. At present, effective drugs for the treatment of dengue fever have not yet appeared, and the dengue vaccines studied in various countries have also experienced severe adverse reactions. Thus it is urgent to find new chemicals against dengue virus. Now we found Sirtuins (SIRTs) were increased during dengue virus infection and tenovin-1, a SIRT1/2 inhibitor, showed an impressive antiviral ability in vitro. In BHK-21 cells, tenovin-1 inhibited the replication of DENV2 with an EC50 at 3.41 ± 1.10 μM, also inhibited other three types of dengue viruses with EC50 at 0.97 ± 1.11 μM, 1.81 ± 1.08 μM, 3.81 ± 1.34 μM respectively. Moreover, the cytopathic effect-induced DENV2 was largely improved by tenovin-1 treatment and the release of progeny viruses was inhibited by tenovin-1 treatment. At the same time, the viral protein level and mRNA level were decreased with tenovin-1 treatment after dengue virus infection. From the drug-addition assay, the tenovin-1 played its antiviral after viral infection, which indicated tenovin-1 was not a microbicide. Apart from its antiviral effect, tenovin-1 inhibited the inflammatory response caused by DENV2, reducing the release of inflammatory factors during viral infection. The antiviral effect of tenovin-1 was abrogated with SIRT agonist or SIRT2 knockdown treatment, which indicated the effect of tenovin-1 was on-target. In conclusion, tenovin-1 was proved to be a promising compound against flavivirus infection through SIRT2, which should be pay more attention for further study.Renal fibrosis is the pathological consequence of progressive chronic kidney disease. Although it has been reported that vitamin D3 exerts antifibrotic effects, the underlying mechanisms remain unclear. This study is aimed at investigating the effects and molecular mechanisms in high-dose vitamin D3 treatment on renal fibrosis. A model of chronic kidney disease was established by 5/6 nephrectomy in rats characterised by high levels of serum creatine, urea nitrogen, and urinary protein. Serum 25-dihydroxyvitamin D3, calcium and parathormone levels were measured to evaluate vitamin D levels. Hematoxylin and eosin, periodic acid Schiff and Mallory's Trichrome staining were used to evaluate histopathological changes in rats. Moreover, the expression of vimentin, collagen I, α-smooth muscle actin and E-cadherin were analyzed at molecular and histopathological levels. Our results showed that exposure to vitamin D3 decreased the levels of serum creatine, urea nitrogen and urine protein and restored the homeostasis of calcium and parathormone. Vitamin D3 also downregulated the expression of vimentin, collagen I and α-smooth muscle actin and attenuated renal fibrosis and epithelial to mesenchymal transition in the kidney. Importantly, vitamin D3 treatment increased the expression of the vitamin D receptor and inhibited Transforming growth factor-β1 (TGF-β1)/Smad3 signaling pathway in rats kidneys with chronic kidney disease. Mechanistically, the upregulation of TGF-β1 and phosphorylation of Smad3 induced by vitamin D3 was reversed by activation of the vitamin D receptor. Our findings indicated that vitamin D3 is a potential antifibrotic drug in chronic kidney disease via the vitmin D receptor and inhibiting TGF-β1/Smad3 signaling pathway.
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  • The novelty of this study lies in its detailed examination of the relationship between manufacturing complexity, manufacturing strategies, and manufacturing performance, particularly in developing countries. The results are expected to fill the existing research gaps.The health-related Sustainable Development Goals (SDGs) and the Coronavirus Pandemic (COVID-19) have recently increased awareness of the need for countries to increase fiscal space for health. Prior to these, many Low and Middle-Income Countries (LMICs) had embraced the concept of Universal Health Coverage (UHC) and have either commenced or are in the process of implementing various models of health insurance in order to provide financial access to health care to their populations. While evidence of a relationship between experimentation with UHC and increased access to and utilisation of health care in LMICs is common, there is inadequate research evidence on the specific health financing model that is most appropriate for pursuing the objectives of UHC in these settings. Drawing on a synthesis of empirical and theoretical discourses on the feasibility of UHC in LMICs, this paper argues that the journey towards UHC is not a 'one size fits all' process, but a long-term policy engagement that requires adaptation to the specific socio-cultural and political economy contexts of implementing countries. The study draws on the WHO's framework for tracking progress towards UHC using the implementation of a mildly progressive pluralistic health financing model in Ghana and advocates a comprehensive discourse on the potential for LMICs to build resilient and responsive health systems to facilitate a gradual transition towards UHC.The difficulty in studying the relationship between stress and emotional regulation is due to the need to contemplate a dynamic perspective that analyzes the moderating role of stress. In fact, stress involves different phases or stages, and the neurocognitive processes involved in emotion regulation differ significantly between these phases. The period of anticipation of stressful events can be fundamental to understand the process of stress regulation; however, surprisingly few works have analyzed the differential activation of brain networks involved in cognitive regulation during the phases of stress and recovery. Taking this into consideration, within this study we propose to analyze in an integrated way the psychological and neurobiological processes during the phase of stress and recovery, with the aim of improving our understanding of the mechanisms that underlie successful and unsuccessful stress regulation. We consider that from the present review we contribute to achieve a better understanding of the mechanisms underlying successful and unsuccessful stress regulation would contribute to the improvement of prevention and treatment interventions for mental disorders.Wheat crop contributes to a major portion of the agriculture economy of Nepal. It is ranked as the third major cereal crop of the country even though, it faces terminal heat stress which speeds up the grain filling rate and shortens the filling period, causing reduction in grain weight, size, number and quality losses. We can minimize this loss through a genotypic selection of high-yielding lines by understanding the genotype-environment interaction. The objective of this research is to obtain a high yielding line with a stable performance across the environments. In order to do so, we conducted an experiment using eighteen elite wheat lines and two check varieties in alpha-lattice design with two replications in different environments viz. irrigated and terminal heat stress environment from November 2019 to April 2020. https://www.selleckchem.com/products/pf-06650833.html The analysis of variance revealed that genotype, environment and their interaction had a highly significant effect on the yield. Furthermore, the which-won-where model indicated specific adaptation of elite lines NL 1179, NL 1420, BL 4407, NL 1368 to the irrigated environment and Bhirkuti to the terminal heat-stressed environment. Similarly, the mean-versus-stability study indicated that elite lines BL 4407, NL 1368, BL 4919, NL 1350, and NL 1420 had above-average yield and higher stability whereas elite lines Gautam, NL 1412, NL 1376, NL 1387, NL 1404, and NL 1381 had below-average yield and lower stability. The ranking of elite lines biplot, PC1 explaining 73.6% and PC2 explaining 26.4% of the interaction effect, showed the rank of elite line, NL 1420 > NL 1368> NL 1350 > other lines, close to the ideal line. On the basis of the obtained results, we recommend NL 1420 with both the high yield and stability is suited across both the environments, while NL 1179 and Bhirkuti is adapted specifically for irrigated and terminal heat stress environment, respectively.This paper examines impacts of adoption of wheat chickpea double cropping on yield and farm income of smallholder rural farmers in Becho district, South West Shewa Zone, Oromia Region, Ethiopia. The study used cross-sectional data collected from 203 smallholder farm households selected randomly through two-stage stratified random sampling technique. Propensity score matching was employed to analyze the impacts of adoption on yield and farm income. The result showed that adoption of wheat-chickpea double cropping has significant impact on yield and farm income of the group of adopter households compared to the group of non-adopters. With regard to yield, adopters harvested average wheat yield of 2120 kg/ha, while the non-adopters harvested average wheat yield of 1420 kg/ha. In addition, the treated households earned average annual farm income of about 709.125 Euro per year from **** of both wheat and chickpea as adopters; while the non-adopters earned average farm income of 129 Euro from **** of wheat. These results imply that scaling out of wheat-chickpea double cropping contributes to food security and rural livelihood improvement through yield and farm income increment. Hence, encouraging farmers towards adoption of wheat-chickpea double cropping is essential for improving livelihoods of rural households by properly addressing factors such as access to improved seeds, training on double cropping, involvement in non-farm income activities, access to broad bed maker (BBM), ownership of tropical livestock unit (TLU) and access to fertilizer.
    The novelty of this study lies in its detailed examination of the relationship between manufacturing complexity, manufacturing strategies, and manufacturing performance, particularly in developing countries. The results are expected to fill the existing research gaps.The health-related Sustainable Development Goals (SDGs) and the Coronavirus Pandemic (COVID-19) have recently increased awareness of the need for countries to increase fiscal space for health. Prior to these, many Low and Middle-Income Countries (LMICs) had embraced the concept of Universal Health Coverage (UHC) and have either commenced or are in the process of implementing various models of health insurance in order to provide financial access to health care to their populations. While evidence of a relationship between experimentation with UHC and increased access to and utilisation of health care in LMICs is common, there is inadequate research evidence on the specific health financing model that is most appropriate for pursuing the objectives of UHC in these settings. Drawing on a synthesis of empirical and theoretical discourses on the feasibility of UHC in LMICs, this paper argues that the journey towards UHC is not a 'one size fits all' process, but a long-term policy engagement that requires adaptation to the specific socio-cultural and political economy contexts of implementing countries. The study draws on the WHO's framework for tracking progress towards UHC using the implementation of a mildly progressive pluralistic health financing model in Ghana and advocates a comprehensive discourse on the potential for LMICs to build resilient and responsive health systems to facilitate a gradual transition towards UHC.The difficulty in studying the relationship between stress and emotional regulation is due to the need to contemplate a dynamic perspective that analyzes the moderating role of stress. In fact, stress involves different phases or stages, and the neurocognitive processes involved in emotion regulation differ significantly between these phases. The period of anticipation of stressful events can be fundamental to understand the process of stress regulation; however, surprisingly few works have analyzed the differential activation of brain networks involved in cognitive regulation during the phases of stress and recovery. Taking this into consideration, within this study we propose to analyze in an integrated way the psychological and neurobiological processes during the phase of stress and recovery, with the aim of improving our understanding of the mechanisms that underlie successful and unsuccessful stress regulation. We consider that from the present review we contribute to achieve a better understanding of the mechanisms underlying successful and unsuccessful stress regulation would contribute to the improvement of prevention and treatment interventions for mental disorders.Wheat crop contributes to a major portion of the agriculture economy of Nepal. It is ranked as the third major cereal crop of the country even though, it faces terminal heat stress which speeds up the grain filling rate and shortens the filling period, causing reduction in grain weight, size, number and quality losses. We can minimize this loss through a genotypic selection of high-yielding lines by understanding the genotype-environment interaction. The objective of this research is to obtain a high yielding line with a stable performance across the environments. In order to do so, we conducted an experiment using eighteen elite wheat lines and two check varieties in alpha-lattice design with two replications in different environments viz. irrigated and terminal heat stress environment from November 2019 to April 2020. https://www.selleckchem.com/products/pf-06650833.html The analysis of variance revealed that genotype, environment and their interaction had a highly significant effect on the yield. Furthermore, the which-won-where model indicated specific adaptation of elite lines NL 1179, NL 1420, BL 4407, NL 1368 to the irrigated environment and Bhirkuti to the terminal heat-stressed environment. Similarly, the mean-versus-stability study indicated that elite lines BL 4407, NL 1368, BL 4919, NL 1350, and NL 1420 had above-average yield and higher stability whereas elite lines Gautam, NL 1412, NL 1376, NL 1387, NL 1404, and NL 1381 had below-average yield and lower stability. The ranking of elite lines biplot, PC1 explaining 73.6% and PC2 explaining 26.4% of the interaction effect, showed the rank of elite line, NL 1420 > NL 1368> NL 1350 > other lines, close to the ideal line. On the basis of the obtained results, we recommend NL 1420 with both the high yield and stability is suited across both the environments, while NL 1179 and Bhirkuti is adapted specifically for irrigated and terminal heat stress environment, respectively.This paper examines impacts of adoption of wheat chickpea double cropping on yield and farm income of smallholder rural farmers in Becho district, South West Shewa Zone, Oromia Region, Ethiopia. The study used cross-sectional data collected from 203 smallholder farm households selected randomly through two-stage stratified random sampling technique. Propensity score matching was employed to analyze the impacts of adoption on yield and farm income. The result showed that adoption of wheat-chickpea double cropping has significant impact on yield and farm income of the group of adopter households compared to the group of non-adopters. With regard to yield, adopters harvested average wheat yield of 2120 kg/ha, while the non-adopters harvested average wheat yield of 1420 kg/ha. In addition, the treated households earned average annual farm income of about 709.125 Euro per year from sale of both wheat and chickpea as adopters; while the non-adopters earned average farm income of 129 Euro from sale of wheat. These results imply that scaling out of wheat-chickpea double cropping contributes to food security and rural livelihood improvement through yield and farm income increment. Hence, encouraging farmers towards adoption of wheat-chickpea double cropping is essential for improving livelihoods of rural households by properly addressing factors such as access to improved seeds, training on double cropping, involvement in non-farm income activities, access to broad bed maker (BBM), ownership of tropical livestock unit (TLU) and access to fertilizer.
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  • A complementary metal-based compilation of the complexes discussed is also provided in a concise tabular form.Rapid screening monofluoroacetic acid (FAcOH) is responsible for preventing chemical poisoning and food safety events. Whereas surface enhanced Raman scattering (SERS) spectra is an effective tool for detecting forbidden chemicals, it is difficult to directly detect FAcOH due to its small Raman scattering cross section as well as weak adsorption on SERS substrates. https://www.selleckchem.com/products/cc-92480.html In this work, the metal phenolic supramolecular networks (MPNs, i.e., the tannic acid and Fe3+ complex) were fabricated on the commercial nanoanodic aluminum oxide film (NAAO) for assisting in situ chemical deposition highly uniform Ag nanostructure over large areas (the NAAO@AgNS). The low cost and simple fabrication process made the NAAO@AgNS a single-use consumable. For FAcOH detection, a specific derivative reaction between FAcOH and thiosalicylic acid (TSA) was introduced. By taking TSA as the Raman probe, its SERS signal attenuated constantly with the increasing amount of FAcOH. For improving quantitative accuracy, thiocyanate (SCN-) was introduced on the NAAO@AgNS as an internal standard; thus, the characteristic peak intensity ratios associated with TSA and SCN- (I1035/I2125) were fitted to the concentration of FAcOH. It was demonstrated that the SERS assay achieved good sensitivity and selection toward FAcOH with the limit of quantitation (LOD) as low as 50 nmol L-1. The NAAO@AgNS featured with highly sensitive, uniform, and consistent SERS performances could easily extend to wide SERS applications.Surface-modified mesoporous silica nanoparticles (MSNs) have attracted more and more attention as promising materials for biomolecule delivery. However, the lack of detailed evaluation relevant to the potential cytotoxicity of these MSNs is still a major obstacle for their applications. Unlike the bare MSNs and amino- or liposome-modified MSNs, we found that polyethylenimine-modified MSNs (MSNs-PEI) had no obvious toxicity to human umbilical vein endothelial cells (HUVECs) at the concentrations up to 100 μg/mL. However, MSNs-PEI induced autophagosomes accumulation by blocking their fusion with lysosomes, an essential mechanism for the cytotoxicity of many nanoparticles (NPs). Thus, we predicted that an alternative pathway for autophagosome clearance exists in HUVECs to relieve autophagic stress induced by MSNs-PEI. We found that MSNs-PEI prevented STX17 loading onto autophagosomes instead of influencing lysosomal pH or proteolytic activity. MSNs-PEI induced the structural alternation of the cytoskeleton but did not cause endoplasmic reticulum stress. The accumulated autophagosomes were released to the extracellular space via microvesicles (MVs) when the autophagic degradation was blocked by MSNs-PEI. More importantly, blockade of either autophagosome formation or release caused the accumulation of damaged mitochondria and excessive ROS production in the MSNs-PEI-treated HUVECs, which in turn led to cell death. Thus, we propose here that the MV-mediated autophagosome release, a compensation mechanism, allows the vascular endothelial cell survival when the degradation of autophagosomes is blocked by MSNs-PEI. Accordingly, promoting the release of accumulated autophagosomes may be a protective strategy against the endothelial toxicity of NPs.For the most part, enzymes contain one active site wherein they catalyze in a serial manner chemical reactions between substrates both efficiently and rapidly. Imagine if a situation could be created within a chiral porous crystal containing trillions of active sites where substrates can reside in vast numbers before being converted in parallel into products. Here, we report how it is possible to incorporate 1-anthracenecarboxylate (1-AC-) as a substrate into a γ-cyclodextrin-containing metal-organic framework (CD-MOF-1), where the metals are K+ cations, prior to carrying out [4+4] photodimerizations between pairs of substrate molecules, affording selectively one of four possible regioisomers. One of the high-yielding regioisomers exhibits optical activity as a result of the presence of an 81 ratio of the two enantiomers following separation by high-performance liquid chromatography. The solid-state superstructure of 1-anthracenecarboxylate potassium salt (1-ACK), which is co-crystallized with γ-cyclodextrin, reveals that pairs of substrate molecules are not only packed inside tunnels between spherical cavities present in CD-MOF-1, but also stabilized-in addition to hydrogen-bonding to the C-2 and C-3 hydroxyl groups on the d-glucopyranosyl residues present in the γ-cyclodextrin tori-by combinations of hydrophobic and electrostatic interactions between the carboxyl groups in 1-AC- and four K+ cations on the waistline between the two γ-cyclodextrin tori in the tunnels. These non-covalent bonding interactions result in preferred co-conformations that account for the highly regio- and enantioselective [4+4] cycloaddition during photoirradiation. Theoretical calculations, in conjunction with crystallography, support the regio- and stereochemical outcome of the photodimerization.Gas solubility can go beyond classical bulk-liquid Henry's law saturation under the nanoconfinement of a liquid phase. This concept establishes the foundation of the current study for developing a novel catalytic system for transformation of carbon dioxide to cyclic carbonates at mild conditions with major emphasis on application for CO2 capture and utilization. A series of mesoporous silica-based supports of various pore sizes and shapes grafted with a quaternary ammonium salt is synthesized and characterized. CO2 sorption in styrene oxide, either in bulk or nanoconfined state, as well as catalytic reactivity for CO2 transformation into styrene carbonate, are experimentally evaluated. The family of mesoporous catalysts with aligned cylindrical pores (MCM-41 and SBA-15) with pore sizes ranging from 3.5 to 9 nm exhibit enhanced sorption of CO2 in nanoconfined styrene oxide with maximum sorption capacity taking place in MCM-41 with the smallest pore size. The catalysts with interconnected cylindrical pores (KIT-6) with pore sizes ranging from 4.
    A complementary metal-based compilation of the complexes discussed is also provided in a concise tabular form.Rapid screening monofluoroacetic acid (FAcOH) is responsible for preventing chemical poisoning and food safety events. Whereas surface enhanced Raman scattering (SERS) spectra is an effective tool for detecting forbidden chemicals, it is difficult to directly detect FAcOH due to its small Raman scattering cross section as well as weak adsorption on SERS substrates. https://www.selleckchem.com/products/cc-92480.html In this work, the metal phenolic supramolecular networks (MPNs, i.e., the tannic acid and Fe3+ complex) were fabricated on the commercial nanoanodic aluminum oxide film (NAAO) for assisting in situ chemical deposition highly uniform Ag nanostructure over large areas (the NAAO@AgNS). The low cost and simple fabrication process made the NAAO@AgNS a single-use consumable. For FAcOH detection, a specific derivative reaction between FAcOH and thiosalicylic acid (TSA) was introduced. By taking TSA as the Raman probe, its SERS signal attenuated constantly with the increasing amount of FAcOH. For improving quantitative accuracy, thiocyanate (SCN-) was introduced on the NAAO@AgNS as an internal standard; thus, the characteristic peak intensity ratios associated with TSA and SCN- (I1035/I2125) were fitted to the concentration of FAcOH. It was demonstrated that the SERS assay achieved good sensitivity and selection toward FAcOH with the limit of quantitation (LOD) as low as 50 nmol L-1. The NAAO@AgNS featured with highly sensitive, uniform, and consistent SERS performances could easily extend to wide SERS applications.Surface-modified mesoporous silica nanoparticles (MSNs) have attracted more and more attention as promising materials for biomolecule delivery. However, the lack of detailed evaluation relevant to the potential cytotoxicity of these MSNs is still a major obstacle for their applications. Unlike the bare MSNs and amino- or liposome-modified MSNs, we found that polyethylenimine-modified MSNs (MSNs-PEI) had no obvious toxicity to human umbilical vein endothelial cells (HUVECs) at the concentrations up to 100 μg/mL. However, MSNs-PEI induced autophagosomes accumulation by blocking their fusion with lysosomes, an essential mechanism for the cytotoxicity of many nanoparticles (NPs). Thus, we predicted that an alternative pathway for autophagosome clearance exists in HUVECs to relieve autophagic stress induced by MSNs-PEI. We found that MSNs-PEI prevented STX17 loading onto autophagosomes instead of influencing lysosomal pH or proteolytic activity. MSNs-PEI induced the structural alternation of the cytoskeleton but did not cause endoplasmic reticulum stress. The accumulated autophagosomes were released to the extracellular space via microvesicles (MVs) when the autophagic degradation was blocked by MSNs-PEI. More importantly, blockade of either autophagosome formation or release caused the accumulation of damaged mitochondria and excessive ROS production in the MSNs-PEI-treated HUVECs, which in turn led to cell death. Thus, we propose here that the MV-mediated autophagosome release, a compensation mechanism, allows the vascular endothelial cell survival when the degradation of autophagosomes is blocked by MSNs-PEI. Accordingly, promoting the release of accumulated autophagosomes may be a protective strategy against the endothelial toxicity of NPs.For the most part, enzymes contain one active site wherein they catalyze in a serial manner chemical reactions between substrates both efficiently and rapidly. Imagine if a situation could be created within a chiral porous crystal containing trillions of active sites where substrates can reside in vast numbers before being converted in parallel into products. Here, we report how it is possible to incorporate 1-anthracenecarboxylate (1-AC-) as a substrate into a γ-cyclodextrin-containing metal-organic framework (CD-MOF-1), where the metals are K+ cations, prior to carrying out [4+4] photodimerizations between pairs of substrate molecules, affording selectively one of four possible regioisomers. One of the high-yielding regioisomers exhibits optical activity as a result of the presence of an 81 ratio of the two enantiomers following separation by high-performance liquid chromatography. The solid-state superstructure of 1-anthracenecarboxylate potassium salt (1-ACK), which is co-crystallized with γ-cyclodextrin, reveals that pairs of substrate molecules are not only packed inside tunnels between spherical cavities present in CD-MOF-1, but also stabilized-in addition to hydrogen-bonding to the C-2 and C-3 hydroxyl groups on the d-glucopyranosyl residues present in the γ-cyclodextrin tori-by combinations of hydrophobic and electrostatic interactions between the carboxyl groups in 1-AC- and four K+ cations on the waistline between the two γ-cyclodextrin tori in the tunnels. These non-covalent bonding interactions result in preferred co-conformations that account for the highly regio- and enantioselective [4+4] cycloaddition during photoirradiation. Theoretical calculations, in conjunction with crystallography, support the regio- and stereochemical outcome of the photodimerization.Gas solubility can go beyond classical bulk-liquid Henry's law saturation under the nanoconfinement of a liquid phase. This concept establishes the foundation of the current study for developing a novel catalytic system for transformation of carbon dioxide to cyclic carbonates at mild conditions with major emphasis on application for CO2 capture and utilization. A series of mesoporous silica-based supports of various pore sizes and shapes grafted with a quaternary ammonium salt is synthesized and characterized. CO2 sorption in styrene oxide, either in bulk or nanoconfined state, as well as catalytic reactivity for CO2 transformation into styrene carbonate, are experimentally evaluated. The family of mesoporous catalysts with aligned cylindrical pores (MCM-41 and SBA-15) with pore sizes ranging from 3.5 to 9 nm exhibit enhanced sorption of CO2 in nanoconfined styrene oxide with maximum sorption capacity taking place in MCM-41 with the smallest pore size. The catalysts with interconnected cylindrical pores (KIT-6) with pore sizes ranging from 4.
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