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Auditory hallucinations (AHs) are certainly the most emblematic experiences in schizophrenia, but visual hallucinations (VHs) are also commonly observed in this developmental psychiatric disorder. Notably, several studies have suggested a possible relationship between the clinical variability in hallucinations' phenomenology and differences in brain development/maturation. In schizophrenia, impairments of the hippocampus, a medial temporal structure involved in mnesic and neuroplastic processes, have been repeatedly associated with hallucinations, particularly in the visual modality. However, the possible neurodevelopmental origin of hippocampal impairments in VHs has never been directly investigated. A classic marker of early atypical hippocampal development is incomplete hippocampal inversion (IHI). In this study, we compared IHI patterns in healthy volunteers, and two subgroups of carefully selected schizophrenia patients experiencing frequent hallucinations (a) those with pure AHs and (b) those with audio-visual hallucinations (A+VH). We found that VHs were associated with a specific IHI pattern. Schizophrenia patients with A+VH exhibited flatter left hippocampi than patients with pure AHs or healthy controls. This result first confirms that the greater clinical impairment observed in A+VH patients may relate to an increased neurodevelopmental weight in this subpopulation. More importantly, these findings bring crucial hints to better specify the sensitivity period of A+VH-related IHI during early brain development.Recognizing human physical activities using wireless sensor networks has attracted significant research interest due to its broad range of applications, such as healthcare, rehabilitation, athletics, and senior monitoring. There are critical challenges inherent in designing a sensor-based activity recognition system operating in and around a lossy medium such as the human body to gain a trade-off among power consumption, cost, computational complexity, and accuracy. We introduce an innovative wireless system based on magnetic induction for human activity recognition to tackle these challenges and constraints. The magnetic induction system is integrated with machine learning techniques to detect a wide range of human motions. This approach is successfully evaluated using synthesized datasets, laboratory measurements, and deep recurrent neural networks.Anthropogenic mineral is absorbing wide concern in the context of circular economy, but its generation mechanism and quantity from product to waste remain unclear. https://www.selleckchem.com/products/u73122.html Here we consider three product groups, 30 products, and use the revised Weibull lifespan model to map the generation of anthropogenic mineral and 23 types of the capsulated materials by targeting their evolution from 2010 to 2050. Total weight of anthropogenic mineral on average in China reached 39 Mt in 2010, but it will double in 2022 and quadruple in 2045. Stocks of precious metals and rare earths will increase faster than most base materials. The total economic potential in yearly-generated anthropogenic mineral is anticipated to grow markedly from 100 billion US$ in 2020 to 400 billion US$ in 2050. Furthermore, anthropogenic mineral of around 20 materials will be capable to meet projected consumption of three product groups by 2050.Lithium-ion batteries have aided the portable electronics revolution for nearly three decades. They are now enabling vehicle electrification and beginning to enter the utility industry. The emergence and dominance of lithium-ion batteries are due to their higher energy density compared to other rechargeable battery systems, enabled by the design and development of high-energy density electrode materials. Basic science research, involving solid-state chemistry and physics, has been at the center of this endeavor, particularly during the 1970s and 1980s. With the award of the 2019 Nobel Prize in Chemistry to the development of lithium-ion batteries, it is enlightening to look **** at the evolution of the cathode chemistry that made the modern lithium-ion technology feasible. This review article provides a reflection on how fundamental studies have facilitated the discovery, optimization, and rational design of three major categories of oxide cathodes for lithium-ion batteries, and a personal perspective on the future of this important area.c-MET receptors are activated in cancers through genomic events like tyrosine kinase domain mutations, juxtamembrane splicing mutation and amplified copy numbers, which can be inhibited by c-MET small molecule inhibitors. Here, we discover that the most common polymorphism known to affect MET gene (N375S), involving the semaphorin domain, confers exquisite binding affinity for HER2 and enables METN375S to interact with HER2 in a ligand-independent fashion. The resultant METN375S/HER2 dimer transduces potent proliferative, pro-invasive and pro-metastatic cues through the HER2 signaling axis to drive aggressive squamous cell carcinomas of the head and neck (HNSCC) and lung (LUSC), and is associated with poor prognosis. Accordingly, HER2 blockers, but not c-MET inhibitors, are paradoxically effective at restraining in vivo and in vitro models expressing METN375S. These results establish METN375S as a biologically distinct and clinically actionable molecular subset of SCCs that are uniquely amenable to HER2 blocking therapies.Exercise training is a powerful means to combat metabolic diseases. **** are extensively used to investigate the benefits of exercise, but mild cold stress induced by ambient housing temperatures may confound translation to humans. Thermoneutral housing is a strategy to make **** more metabolically similar to humans but its effects on exercise adaptations are unknown. Here we show that thermoneutral housing blunts exercise-induced improvements in insulin action in muscle and adipose tissue and reduces the effects of training on energy expenditure, body composition, and muscle and adipose tissue protein expressions. Thus, many reported effects of exercise training in **** are likely secondary to metabolic stress of ambient housing temperature, making it challenging to translate to humans. We conclude that adaptations to exercise training in **** critically depend upon housing temperature. Our findings underscore housing temperature as a critical parameter in the design and interpretation of murine exercise training studies.
Auditory hallucinations (AHs) are certainly the most emblematic experiences in schizophrenia, but visual hallucinations (VHs) are also commonly observed in this developmental psychiatric disorder. Notably, several studies have suggested a possible relationship between the clinical variability in hallucinations' phenomenology and differences in brain development/maturation. In schizophrenia, impairments of the hippocampus, a medial temporal structure involved in mnesic and neuroplastic processes, have been repeatedly associated with hallucinations, particularly in the visual modality. However, the possible neurodevelopmental origin of hippocampal impairments in VHs has never been directly investigated. A classic marker of early atypical hippocampal development is incomplete hippocampal inversion (IHI). In this study, we compared IHI patterns in healthy volunteers, and two subgroups of carefully selected schizophrenia patients experiencing frequent hallucinations (a) those with pure AHs and (b) those with audio-visual hallucinations (A+VH). We found that VHs were associated with a specific IHI pattern. Schizophrenia patients with A+VH exhibited flatter left hippocampi than patients with pure AHs or healthy controls. This result first confirms that the greater clinical impairment observed in A+VH patients may relate to an increased neurodevelopmental weight in this subpopulation. More importantly, these findings bring crucial hints to better specify the sensitivity period of A+VH-related IHI during early brain development.Recognizing human physical activities using wireless sensor networks has attracted significant research interest due to its broad range of applications, such as healthcare, rehabilitation, athletics, and senior monitoring. There are critical challenges inherent in designing a sensor-based activity recognition system operating in and around a lossy medium such as the human body to gain a trade-off among power consumption, cost, computational complexity, and accuracy. We introduce an innovative wireless system based on magnetic induction for human activity recognition to tackle these challenges and constraints. The magnetic induction system is integrated with machine learning techniques to detect a wide range of human motions. This approach is successfully evaluated using synthesized datasets, laboratory measurements, and deep recurrent neural networks.Anthropogenic mineral is absorbing wide concern in the context of circular economy, but its generation mechanism and quantity from product to waste remain unclear. https://www.selleckchem.com/products/u73122.html Here we consider three product groups, 30 products, and use the revised Weibull lifespan model to map the generation of anthropogenic mineral and 23 types of the capsulated materials by targeting their evolution from 2010 to 2050. Total weight of anthropogenic mineral on average in China reached 39 Mt in 2010, but it will double in 2022 and quadruple in 2045. Stocks of precious metals and rare earths will increase faster than most base materials. The total economic potential in yearly-generated anthropogenic mineral is anticipated to grow markedly from 100 billion US$ in 2020 to 400 billion US$ in 2050. Furthermore, anthropogenic mineral of around 20 materials will be capable to meet projected consumption of three product groups by 2050.Lithium-ion batteries have aided the portable electronics revolution for nearly three decades. They are now enabling vehicle electrification and beginning to enter the utility industry. The emergence and dominance of lithium-ion batteries are due to their higher energy density compared to other rechargeable battery systems, enabled by the design and development of high-energy density electrode materials. Basic science research, involving solid-state chemistry and physics, has been at the center of this endeavor, particularly during the 1970s and 1980s. With the award of the 2019 Nobel Prize in Chemistry to the development of lithium-ion batteries, it is enlightening to look back at the evolution of the cathode chemistry that made the modern lithium-ion technology feasible. This review article provides a reflection on how fundamental studies have facilitated the discovery, optimization, and rational design of three major categories of oxide cathodes for lithium-ion batteries, and a personal perspective on the future of this important area.c-MET receptors are activated in cancers through genomic events like tyrosine kinase domain mutations, juxtamembrane splicing mutation and amplified copy numbers, which can be inhibited by c-MET small molecule inhibitors. Here, we discover that the most common polymorphism known to affect MET gene (N375S), involving the semaphorin domain, confers exquisite binding affinity for HER2 and enables METN375S to interact with HER2 in a ligand-independent fashion. The resultant METN375S/HER2 dimer transduces potent proliferative, pro-invasive and pro-metastatic cues through the HER2 signaling axis to drive aggressive squamous cell carcinomas of the head and neck (HNSCC) and lung (LUSC), and is associated with poor prognosis. Accordingly, HER2 blockers, but not c-MET inhibitors, are paradoxically effective at restraining in vivo and in vitro models expressing METN375S. These results establish METN375S as a biologically distinct and clinically actionable molecular subset of SCCs that are uniquely amenable to HER2 blocking therapies.Exercise training is a powerful means to combat metabolic diseases. Mice are extensively used to investigate the benefits of exercise, but mild cold stress induced by ambient housing temperatures may confound translation to humans. Thermoneutral housing is a strategy to make mice more metabolically similar to humans but its effects on exercise adaptations are unknown. Here we show that thermoneutral housing blunts exercise-induced improvements in insulin action in muscle and adipose tissue and reduces the effects of training on energy expenditure, body composition, and muscle and adipose tissue protein expressions. Thus, many reported effects of exercise training in mice are likely secondary to metabolic stress of ambient housing temperature, making it challenging to translate to humans. We conclude that adaptations to exercise training in mice critically depend upon housing temperature. Our findings underscore housing temperature as a critical parameter in the design and interpretation of murine exercise training studies.0 Comments 0 Shares 0 Views 0 ReviewsPlease log in to like, share and comment! -
Résultats Un total de 181 participants ont été recrutés pendant la période d'étude. 114 étaient des hommes. Cent douze participants (61,8%) ont eu stade 5 CKD, dont 97 avaient commencé une hémodialyse de maintenance. La prévalence de la LR était de 44,8% (81/181) (intervalle de confiance à 95% 37,4% à 51,9%). Le manque de fonds est la raison la plus fréquemment invoquée par les participants qui ont tardé après avoir été officiellement dirigés vers un néphrologue. Étant un diabétique connu était associé à la LR. L'âge, le sexe, le niveau d'éducation, la profession, être un hypertendu connu ou un diabétique connu étaient prédicteurs non significatifs de la LR. Conclusion La prévalence de la LR est élevée. Education des médecins, des patients et du grand public sur les premiers symptômes et les signes physiques de la maladie rénale est nécessaire. L'initiation d'un régime d'assurance maladie global est nécessaire pour résoudre le problème du manque de fonds pour la consultation et le traitement médicaux.in English, French Résumé Contexte La prévalence de l'hypertension et du diabète augmente au Ghana et en Afrique subsaharienne. Le dépistage est un outil utile pour améliorer la détection précoce des deux maladies afin de réduire la mortalité et la morbidité associées à ces affections. Cette étude visait à déterminer la prévalence de l'hypertension et de l'hyperglycémie chez les patients fréquentant une clinique dentaire à Accra. Méthodes Une étude transversale, modélisant un exercice de dépistage, a été menée dans une grande clinique dentaire à Accra. L'hypertension artérielle et le diabète ont fait l'objet d'un dépistage au moyen d'une vérification sérielle de la tension artérielle au repos et de mesures aléatoires de la glycémie, respectivement. Les autres variables étaient le pouls, la fréquence respiratoire et les caractéristiques de base des répondants. https://www.selleckchem.com/products/PD-0325901.html Les données ont été analysées à l'aide de la version 14 de Stata, et des statistiques descriptives ont été produites et présentées. Résultats Au total, 175 participants ont participé à l'étude, dont 76 hommes (43,4 %) et 99 femmes (56,6 %). Cela représentait un ratio hommes/femmes de 0,81. L'âge variait de 18 à 86 ans, l'âge médian et l'âge moyen étant respectivement de 40 ans et 43,1 ans (±16,9 ans). Cette étude a révélé que la prévalence de l'hypertension et de l'hyperglycémie à la clinique dentaire était de 31,4 % et 24,6 %, respectivement. Conclusion Les résultats de cette étude démontrent l'importance de la clinique dentaire dans la détection de l'hypertension et du diabète non diagnostiqués, ainsi que de ceux qui ont déjà reçu un diagnostic, mais dont la tension artérielle et la glycémie ne sont pas sous contrôle adéquat. Avec des références efficaces et des systèmes de suivi en place dans les cabinets dentaires, ils pourraient être exploités comme un lieu fertile pour le dépistage de l'hypertension et du diabète.in English, French Résumé Contexte L'adolescence est caractérisée par un rythme de croissance considérable, des changements biologiques et psychosociaux. Cela peut se traduire par rapide. l'augmentation des paramètres anthropométriques et l'indulgence dans les comportements à risque des jeunes, et ce sont les facteurs de risque de l'hypertension artérielle (HTN). But Cette étude visait à déterminer le profil de pression artérielle oscillométrique d'adolescents apparemment sains du secondaire en La métropole d'Abakaliki et ses relations avec le sexe et les variables anthropométriques. Sujets et méthodes Ce processus en plusieurs étapes sélectionné 2401 étudiants âgés de 10 à 19 ans entre août 2015 et janvier 2016. La mesure de la pression artérielle a été réalisée à l'aide de la méthode oscillométrique.Des informations sur les facteurs de risque modifiables pour HTN ont été obtenues. Les paramètres anthropométriques ont été mesurés. Les données ont été analysées avec la méthode de Student.test t, analyse de va surveillance systématique de la TA est recommandée chez les adolescents, en particulier ceux à risque prédominant facteurs, y compris des antécédents familiaux de HTN, d'obésité et d'abus de substances et d'alcool. Une détection précoce aidera à atténuer les effets de ces facteurs de risque cardiovasculaires.in English, French Résumé Introductıon Le but de cette étude est de présenter nos 20 ans dæexpérience de læadrénalectomie ouverte (OA) lors de la laparoscopie dans un pays en développement. Matériaux et méthodes Une étude rétrospective et descriptive a été prévue dans le service de chirurgie générale de notre hôpital, incluant des patients ayant subi entre janvier 1993 et janvier 2013 une adrénalectomie ouverte pour une masse adrrénalienne. Toutes les opérations ont été effectuées par 2 chirurgiens. Résultats Quatre-vingt-dix patients qui ont subi une adrénalectomie ouverte dans notre clinique ont été évalués rétrospectivement. Le nombre moyen dæopérations adrénaliennes par mois au cours de cette période était de 0,38 ± 0,12. Læâge moyen des patients était de 46,4 ± 17 ans 35 (38,8%) étaient des hommes et 55 (61,2%) étaient des femmes. Læindice de masse corporelle (IMC) moyen était de 28,4 ± 5,25 et le score moyen de læAmerican Society of Anesthesiologists (ASA) était de 2,6 ± 0,57. La durée moyenne d'opération était de 88 ± 27 minutes. Le diamètre moyen de toutes les lésions était de 4,8 ± 1,3 cm (entre 1,2 et 21 cm). La quantité moyenne de saignements rencontrés au cours des opérations était de 118 ± 23 ml. Des complications postopératoires ont été observées chez quatre patients (5,5%). La mortalité næa été observée chez aucun des patients. La durée moyenne dæhospitalisation était de 6,2 ± 2,1 jours. Le type histologique le plus courant était læadénome bénin (48,8%). Conclusion Dans un pays en développement, læadrénalectomie ouverte est une alternative sûre à læadrénalectomie laparoscopique qui a une courbe dæapprentissage difficile.
Résultats Un total de 181 participants ont été recrutés pendant la période d'étude. 114 étaient des hommes. Cent douze participants (61,8%) ont eu stade 5 CKD, dont 97 avaient commencé une hémodialyse de maintenance. La prévalence de la LR était de 44,8% (81/181) (intervalle de confiance à 95% 37,4% à 51,9%). Le manque de fonds est la raison la plus fréquemment invoquée par les participants qui ont tardé après avoir été officiellement dirigés vers un néphrologue. Étant un diabétique connu était associé à la LR. L'âge, le sexe, le niveau d'éducation, la profession, être un hypertendu connu ou un diabétique connu étaient prédicteurs non significatifs de la LR. Conclusion La prévalence de la LR est élevée. Education des médecins, des patients et du grand public sur les premiers symptômes et les signes physiques de la maladie rénale est nécessaire. L'initiation d'un régime d'assurance maladie global est nécessaire pour résoudre le problème du manque de fonds pour la consultation et le traitement médicaux.in English, French Résumé Contexte La prévalence de l'hypertension et du diabète augmente au Ghana et en Afrique subsaharienne. Le dépistage est un outil utile pour améliorer la détection précoce des deux maladies afin de réduire la mortalité et la morbidité associées à ces affections. Cette étude visait à déterminer la prévalence de l'hypertension et de l'hyperglycémie chez les patients fréquentant une clinique dentaire à Accra. Méthodes Une étude transversale, modélisant un exercice de dépistage, a été menée dans une grande clinique dentaire à Accra. L'hypertension artérielle et le diabète ont fait l'objet d'un dépistage au moyen d'une vérification sérielle de la tension artérielle au repos et de mesures aléatoires de la glycémie, respectivement. Les autres variables étaient le pouls, la fréquence respiratoire et les caractéristiques de base des répondants. https://www.selleckchem.com/products/PD-0325901.html Les données ont été analysées à l'aide de la version 14 de Stata, et des statistiques descriptives ont été produites et présentées. Résultats Au total, 175 participants ont participé à l'étude, dont 76 hommes (43,4 %) et 99 femmes (56,6 %). Cela représentait un ratio hommes/femmes de 0,81. L'âge variait de 18 à 86 ans, l'âge médian et l'âge moyen étant respectivement de 40 ans et 43,1 ans (±16,9 ans). Cette étude a révélé que la prévalence de l'hypertension et de l'hyperglycémie à la clinique dentaire était de 31,4 % et 24,6 %, respectivement. Conclusion Les résultats de cette étude démontrent l'importance de la clinique dentaire dans la détection de l'hypertension et du diabète non diagnostiqués, ainsi que de ceux qui ont déjà reçu un diagnostic, mais dont la tension artérielle et la glycémie ne sont pas sous contrôle adéquat. Avec des références efficaces et des systèmes de suivi en place dans les cabinets dentaires, ils pourraient être exploités comme un lieu fertile pour le dépistage de l'hypertension et du diabète.in English, French Résumé Contexte L'adolescence est caractérisée par un rythme de croissance considérable, des changements biologiques et psychosociaux. Cela peut se traduire par rapide. l'augmentation des paramètres anthropométriques et l'indulgence dans les comportements à risque des jeunes, et ce sont les facteurs de risque de l'hypertension artérielle (HTN). But Cette étude visait à déterminer le profil de pression artérielle oscillométrique d'adolescents apparemment sains du secondaire en La métropole d'Abakaliki et ses relations avec le sexe et les variables anthropométriques. Sujets et méthodes Ce processus en plusieurs étapes sélectionné 2401 étudiants âgés de 10 à 19 ans entre août 2015 et janvier 2016. La mesure de la pression artérielle a été réalisée à l'aide de la méthode oscillométrique.Des informations sur les facteurs de risque modifiables pour HTN ont été obtenues. Les paramètres anthropométriques ont été mesurés. Les données ont été analysées avec la méthode de Student.test t, analyse de va surveillance systématique de la TA est recommandée chez les adolescents, en particulier ceux à risque prédominant facteurs, y compris des antécédents familiaux de HTN, d'obésité et d'abus de substances et d'alcool. Une détection précoce aidera à atténuer les effets de ces facteurs de risque cardiovasculaires.in English, French Résumé Introductıon Le but de cette étude est de présenter nos 20 ans dæexpérience de læadrénalectomie ouverte (OA) lors de la laparoscopie dans un pays en développement. Matériaux et méthodes Une étude rétrospective et descriptive a été prévue dans le service de chirurgie générale de notre hôpital, incluant des patients ayant subi entre janvier 1993 et janvier 2013 une adrénalectomie ouverte pour une masse adrrénalienne. Toutes les opérations ont été effectuées par 2 chirurgiens. Résultats Quatre-vingt-dix patients qui ont subi une adrénalectomie ouverte dans notre clinique ont été évalués rétrospectivement. Le nombre moyen dæopérations adrénaliennes par mois au cours de cette période était de 0,38 ± 0,12. Læâge moyen des patients était de 46,4 ± 17 ans 35 (38,8%) étaient des hommes et 55 (61,2%) étaient des femmes. Læindice de masse corporelle (IMC) moyen était de 28,4 ± 5,25 et le score moyen de læAmerican Society of Anesthesiologists (ASA) était de 2,6 ± 0,57. La durée moyenne d'opération était de 88 ± 27 minutes. Le diamètre moyen de toutes les lésions était de 4,8 ± 1,3 cm (entre 1,2 et 21 cm). La quantité moyenne de saignements rencontrés au cours des opérations était de 118 ± 23 ml. Des complications postopératoires ont été observées chez quatre patients (5,5%). La mortalité næa été observée chez aucun des patients. La durée moyenne dæhospitalisation était de 6,2 ± 2,1 jours. Le type histologique le plus courant était læadénome bénin (48,8%). Conclusion Dans un pays en développement, læadrénalectomie ouverte est une alternative sûre à læadrénalectomie laparoscopique qui a une courbe dæapprentissage difficile.0 Comments 0 Shares 0 Views 0 Reviews -
It also binds components of the extracellular matrix in involved tissues. Conversely, CRP in its pentameric isoform (pCRP), which is the form quantified in diagnostic measurements of CRP, is notably less bioactive with weak anti-inflammatory bioactivity. Its accumulation in blood is associated with a continuous, low-level inflammatory response and is indicative of unresolved and advancing disease, as occurs in cancer. Herein, a novel interpretation of the diagnostic utility of CRP is presented accounting for the unique properties of the CRP isoforms in the context of the developing pro-metastatic tumor microenvironment.Acute myeloid leukemia (AML) is a fatal disease characterized by the accumulation of immature myeloid blasts in the bone marrow (BM). Cytokine provide signals for leukemia cells to improve their survival in the BM microenvironment. Previously, we identified interleukin-33 (IL-33) as a promoter of cell survival in a human AML cell line and primary mouse leukemia cells. In this study, we report that the cell surface expression of IL-33-specific receptor, Interleukin 1 Receptor Like 1 (IL1RL1), is elevated in BM cells from AML patients at diagnosis, and the serum level of IL-33 in AML patients is higher than that of healthy donor controls. Moreover, IL-33 levels are found to be positively associated with IL-6 levels in pediatric patients with AML. https://www.selleckchem.com/products/sw033291.html In vitro, IL-33 treatment increased IL-6 mRNA expression and protein level in BM and peripheral blood (PB) cells from AML patients. Evidence was also provided that IL-33 inhibits cell apoptosis by activating p38 mitogen-activated protein kinase (MAPK) pathway using human AML cell line and AML patient samples. Finally, we confirmed that IL-33 activated IL-6 expression in a manner that required p38 MAPK pathway using clinical AML samples. Taken together, we identified a potential mechanism of IL-33-mediated survival involving p38 MAPK in pediatric AML patients that would facilitate future drug development.The concept of adjuvants or adjuvant systems, used in vaccines, exploit evolutionary relationships associated with how the immune system may initially respond to a foreign antigen or pathogen, thus mimicking natural exposure. This is particularly relevant during the non-specific innate stage of the immune response; as such, the quality of this response may dictate specific adaptive responses and conferred memory/protection to that specific antigen or pathogen. Therefore, adjuvants may optimise this response in the most appropriate way for a specific disease. The most commonly used traditional adjuvants are aluminium salts; however, a biodegradable adjuvant, MCT®, was developed for application in the niche area of allergy immunotherapy (AIT), also in combination with a TLR-4 adjuvant-Monophosphoryl Lipid A (MPL®)-producing the first adjuvant system approach for AIT in the clinic. In the last decade, the use and effectiveness of MCT® across a variety of disease models in the preclinical setting highlight it as a promising platform for adjuvant systems, to help overcome the challenges of modern vaccines. A consequence of bringing together, for the first time, a unified view of MCT® mode-of-action from multiple experiments and adjuvant systems will help facilitate future rational design of vaccines while shaping their success.Allogeneic hematopoietic stem cell transplantation is a potentially curative procedure for many malignant diseases. Donor T cells prevent disease recurrence via graft-versus-leukemia (GVL) effect. Donor T cells also contribute to graft-versus-host disease (GVHD), a debilitating and potentially fatal complication. Novel treatment strategies are needed which allow preservation of GVL effects without causing GVHD. Using murine models, we show that targeting IL-2-inducible T cell kinase (ITK) in donor T cells reduces GVHD while preserving GVL effects. Both CD8+ and CD4+ donor T cells from Itk-/- **** produce less inflammatory cytokines and show decrease migration to GVHD target organs such as the liver and small intestine, while maintaining GVL efficacy against primary B-cell acute lymphoblastic leukemia (B-ALL). Itk-/- T cells exhibit reduced expression of IRF4 and decreased JAK/STAT signaling activity but upregulating expression of Eomesodermin (Eomes) and preserve cytotoxicity, necessary for GVL effect. Transcriptome analysis indicates that ITK signaling controls chemokine receptor expression during alloactivation, which in turn affects the ability of donor T cells to migrate to GVHD target organs. Our data suggest that inhibiting ITK could be a therapeutic strategy to reduce GVHD while preserving the beneficial GVL effects following allo-HSCT treatment.Type 1 diabetes mellitus (T1DM) is a complex autoimmune disorder that mainly affects children and adolescents. The elevated blood glucose level of patients with T1DM results from absolute insulin deficiency and leads to hyperglycemia and the development of life-threatening diabetic complications. Although great efforts have been made to elucidate the pathogenesis of this disease, the precise underlying mechanisms are still obscure. Emerging evidence indicates that small extracellular vesicles, namely, exosomes, take part in intercellular communication and regulate interorgan crosstalk. More importantly, many findings suggest that exosomes and their cargo are associated with the development of T1DM. Therefore, a deeper understanding of exosomes is beneficial for further elucidating the pathogenic process of T1DM. Exosomes are promising biomarkers for evaluating the risk of developingty T1DM, monitoring the disease state and predicting related complications because their number and composition can reflect the status of their parent cells. Additionally, since exosomes are natural carriers of functional proteins, RNA and DNA, they can be used as therapeutic tools to deliver these molecules and drugs. In this review, we briefly introduce the current understanding of exosomes. Next, we focus on the relationship between exosomes and T1DM from three perspectives, i.e., the pathogenic role of exosomes in T1DM, exosomes as novel biomarkers of T1DM and exosomes as therapeutic tools for T1DM.
It also binds components of the extracellular matrix in involved tissues. Conversely, CRP in its pentameric isoform (pCRP), which is the form quantified in diagnostic measurements of CRP, is notably less bioactive with weak anti-inflammatory bioactivity. Its accumulation in blood is associated with a continuous, low-level inflammatory response and is indicative of unresolved and advancing disease, as occurs in cancer. Herein, a novel interpretation of the diagnostic utility of CRP is presented accounting for the unique properties of the CRP isoforms in the context of the developing pro-metastatic tumor microenvironment.Acute myeloid leukemia (AML) is a fatal disease characterized by the accumulation of immature myeloid blasts in the bone marrow (BM). Cytokine provide signals for leukemia cells to improve their survival in the BM microenvironment. Previously, we identified interleukin-33 (IL-33) as a promoter of cell survival in a human AML cell line and primary mouse leukemia cells. In this study, we report that the cell surface expression of IL-33-specific receptor, Interleukin 1 Receptor Like 1 (IL1RL1), is elevated in BM cells from AML patients at diagnosis, and the serum level of IL-33 in AML patients is higher than that of healthy donor controls. Moreover, IL-33 levels are found to be positively associated with IL-6 levels in pediatric patients with AML. https://www.selleckchem.com/products/sw033291.html In vitro, IL-33 treatment increased IL-6 mRNA expression and protein level in BM and peripheral blood (PB) cells from AML patients. Evidence was also provided that IL-33 inhibits cell apoptosis by activating p38 mitogen-activated protein kinase (MAPK) pathway using human AML cell line and AML patient samples. Finally, we confirmed that IL-33 activated IL-6 expression in a manner that required p38 MAPK pathway using clinical AML samples. Taken together, we identified a potential mechanism of IL-33-mediated survival involving p38 MAPK in pediatric AML patients that would facilitate future drug development.The concept of adjuvants or adjuvant systems, used in vaccines, exploit evolutionary relationships associated with how the immune system may initially respond to a foreign antigen or pathogen, thus mimicking natural exposure. This is particularly relevant during the non-specific innate stage of the immune response; as such, the quality of this response may dictate specific adaptive responses and conferred memory/protection to that specific antigen or pathogen. Therefore, adjuvants may optimise this response in the most appropriate way for a specific disease. The most commonly used traditional adjuvants are aluminium salts; however, a biodegradable adjuvant, MCT®, was developed for application in the niche area of allergy immunotherapy (AIT), also in combination with a TLR-4 adjuvant-Monophosphoryl Lipid A (MPL®)-producing the first adjuvant system approach for AIT in the clinic. In the last decade, the use and effectiveness of MCT® across a variety of disease models in the preclinical setting highlight it as a promising platform for adjuvant systems, to help overcome the challenges of modern vaccines. A consequence of bringing together, for the first time, a unified view of MCT® mode-of-action from multiple experiments and adjuvant systems will help facilitate future rational design of vaccines while shaping their success.Allogeneic hematopoietic stem cell transplantation is a potentially curative procedure for many malignant diseases. Donor T cells prevent disease recurrence via graft-versus-leukemia (GVL) effect. Donor T cells also contribute to graft-versus-host disease (GVHD), a debilitating and potentially fatal complication. Novel treatment strategies are needed which allow preservation of GVL effects without causing GVHD. Using murine models, we show that targeting IL-2-inducible T cell kinase (ITK) in donor T cells reduces GVHD while preserving GVL effects. Both CD8+ and CD4+ donor T cells from Itk-/- mice produce less inflammatory cytokines and show decrease migration to GVHD target organs such as the liver and small intestine, while maintaining GVL efficacy against primary B-cell acute lymphoblastic leukemia (B-ALL). Itk-/- T cells exhibit reduced expression of IRF4 and decreased JAK/STAT signaling activity but upregulating expression of Eomesodermin (Eomes) and preserve cytotoxicity, necessary for GVL effect. Transcriptome analysis indicates that ITK signaling controls chemokine receptor expression during alloactivation, which in turn affects the ability of donor T cells to migrate to GVHD target organs. Our data suggest that inhibiting ITK could be a therapeutic strategy to reduce GVHD while preserving the beneficial GVL effects following allo-HSCT treatment.Type 1 diabetes mellitus (T1DM) is a complex autoimmune disorder that mainly affects children and adolescents. The elevated blood glucose level of patients with T1DM results from absolute insulin deficiency and leads to hyperglycemia and the development of life-threatening diabetic complications. Although great efforts have been made to elucidate the pathogenesis of this disease, the precise underlying mechanisms are still obscure. Emerging evidence indicates that small extracellular vesicles, namely, exosomes, take part in intercellular communication and regulate interorgan crosstalk. More importantly, many findings suggest that exosomes and their cargo are associated with the development of T1DM. Therefore, a deeper understanding of exosomes is beneficial for further elucidating the pathogenic process of T1DM. Exosomes are promising biomarkers for evaluating the risk of developingty T1DM, monitoring the disease state and predicting related complications because their number and composition can reflect the status of their parent cells. Additionally, since exosomes are natural carriers of functional proteins, RNA and DNA, they can be used as therapeutic tools to deliver these molecules and drugs. In this review, we briefly introduce the current understanding of exosomes. Next, we focus on the relationship between exosomes and T1DM from three perspectives, i.e., the pathogenic role of exosomes in T1DM, exosomes as novel biomarkers of T1DM and exosomes as therapeutic tools for T1DM.0 Comments 0 Shares 0 Views 0 Reviews -
Accordingly, the effect of miR-206 mimics was attenuated by the overexpression of KLF4 in adipocytes. Taken together, we identified the expression profiles of miRNAs in adipocytes, which revealed that miR-206 acts as a suppressor of adipogenesis.Gas chromatography-mass spectrometry (GC-MS) analysis revealed that castasterone and its biosynthetic precursors are found in Brachypodium distachyon. In vitro conversion experiments with crude enzyme solutions prepared from B. distachyon demonstrated the presence of the following biosynthetic sequences campesterol → campesta-4-en-3-one → campesta-3-one → campestanol → 6-deoxocathasterone → 6-deoxoteasterone → teasterone ↔ 3-dehydroteasterone ↔ typhasterol → castasterone. campesterol → 22-hydroxycampesterol → 22-hydroxy-campesta-4-en-3-one → 22-hydroxy-campesta-3-one → 6-deoxo-3-dehydroteasterone → 3-dehydroteasterone. 6-deoxoteasterone ↔ 6-deoxo-3-dehydroteasterone ↔ 6-deoxotyphasterol → 6-deoxocastasterone → castasterone. This shows that there are campestanol-dependent and campestanol-independent pathway in B. distachyon that synthesize 24-methylated brassinosteroids (BRs). Biochemical analysis of BRs biosynthetic enzymes confirmed that BdDET2, BdCYP90B1, BdCYP90A1, BdCYP90D2, and BdCYP85A1 are orthologous to BR 5α-reductase, BR C-22 hydroxylase, BR C-3 oxidase, BR C-23 hydroxylase, and BR C-6 oxidase, respectively. Brassinolide was not identified in B. distachyon. Additionally, B. distachyon crude enzyme solutions could not catalyze the conversion of castasterone to brassinolide, and the gene encoding an ortholog of CYP85A2 (a brassinolide synthase) was not found in B. distachyon. These results strongly suggest that the end product for brassinosteroid biosynthesis which controls the growth and development of B. distachyon is not brassinolide but rather castasterone.Brominated azo dyes (BADs) have been identified as predominant indoor brominated pollutants in daycare dust; thus, their potential health risk to children is of concern. However, the toxicities of BADs remain elusive. In this study, the toxicokinetics of two predominant BADs, Disperse Blue 373 (DB373) and Disperse Violet 93 (DV93), and their suspect metabolite 2-bromo-4,6-dinitroaniline (BDNA) was investigated in embryos of zebrafish (Danio rerio). The bioconcentration factor of DV93 at 120 hpf is 6.2-fold lower than that of DB373. The nontarget analysis revealed distinct metabolism routes between DB373 and DV93 by reducing nitro groups to nitroso (DB373) or amine (DV93), despite their similar structures. NAD(P)H quinone oxidoreductase 1 (NQO1) and pyruvate dehydrogenase were predicted as the enzymes responsible for the reduction of DB373 and DV93 by correlating time courses of the metabolites and enzyme development. Further in vitro recombinant enzyme and in vivo inhibition results validated NQO1 as the enzyme specifically reducing DB373, but not DV93. Global proteome profiling revealed that the expression levels of proteins from the "apoptosis-induced DNA fragmentation" pathway were significantly upregulated by all three BADs, supporting the bioactivation of BADs to mutagenic aromatic amines. This study discovered the bioactivation of BADs via distinct eukaryotic enzymes, implying their potential health risks.Matrix-assisted laser desorption ionization mass spectrometry imaging (MALDI-MSI) is widely used to visualize and analyze the distribution of membrane lipids in an increasingly large number of applications. https://www.selleckchem.com/products/Chlorogenic-acid.html In this context, different lipoforms of glycerophospholipids (GPLs) are among the prime targets of interest. For this group of analytes, however, ion suppression effects have been described to strongly favor the detection of certain GPL classes over others, thereby hampering the analysis of suppressed species and greatly restraining quantitative analysis. These effects are generally attributed to the distribution of available charge carriers during the MALDI process. Here, we present a systematic investigation of charge distribution between different classes of GPL under MALDI-MSI conditions. For this, we constructed arrays of artificial tissues with different formulated lipid composition that contained predefined amounts of only two specific GPL classes and analyzed them with MALDI-MSI in positive- and negative-ion modes. Next to a characterization of expected ion suppression effects, analysis of these binary systems revealed yet undescribed signal intensity enhancement for the combinations of certain GPL classes. Furthermore, the comprehensive data allowed us to compile a hierarchy of charge affinities for the investigated GPL classes in both polarities. Additional experiments revealed that laser post-ionization (MALDI-2) has great potential to overwrite changes in signal intensity caused by charge distribution among different GPL classes observed in standard MALDI-MSI.Functionalized gold nanoparticles are investigated by density functional theory calculations in the context of cancer radiotherapy. Several typical experimental shapes, including nanostars, nanospheres, and nanorods, are modeled by optimizing Au clusters covered by organic monolayers composed of hydrated short-chain polyethylene glycol (PEG) ligands. The PEGylation stabilizes significantly the stellation of decahedral Au54 by deforming significantly its geometry at the spikes. The higher stability of the PEG molecules adsorbed on this stellated nanocluster with respect to the more spherical icosahedral Au55 and truncated octahedral Au79 leads to a larger energy cost to desorb them and thus a weaker propensity for the starred nanoparticle to exchange ligands with the cell membrane, in agreement with experiments. These results open interesting possibilities for advancing our understanding of the cellular uptake of gold nanoparticles.The broad synthetic utility of organoboron compounds stems from their ready ability to undergo 1,2-migrations. Normally, such shifts are induced by α-leaving groups or by reactions of alkenyl boronates with electrophiles. Herein, we present a new strategy to induce 1,2-metalate rearrangements, via ring expansion of vinylcyclopropyl boronate complexes activated by electrophiles. This leads to a cyclopropane-stabilized carbocation, which triggers ring expansion and concomitant 1,2-metalate rearrangement. This novel process delivers medicinally relevant 1,2-substituted cyclobutyl boronic esters with high levels of diastereoselectivity. A wide range of organolithiums and Grignard reagents, electrophiles, and vinylcyclopropyl boronic esters can be used. The methodology was applied to a short, stereoselective synthesis of (±)-grandisol. Computational studies indicate that the reaction proceeds via a nonclassical carbocation followed by anti-1,2-migration.
Accordingly, the effect of miR-206 mimics was attenuated by the overexpression of KLF4 in adipocytes. Taken together, we identified the expression profiles of miRNAs in adipocytes, which revealed that miR-206 acts as a suppressor of adipogenesis.Gas chromatography-mass spectrometry (GC-MS) analysis revealed that castasterone and its biosynthetic precursors are found in Brachypodium distachyon. In vitro conversion experiments with crude enzyme solutions prepared from B. distachyon demonstrated the presence of the following biosynthetic sequences campesterol → campesta-4-en-3-one → campesta-3-one → campestanol → 6-deoxocathasterone → 6-deoxoteasterone → teasterone ↔ 3-dehydroteasterone ↔ typhasterol → castasterone. campesterol → 22-hydroxycampesterol → 22-hydroxy-campesta-4-en-3-one → 22-hydroxy-campesta-3-one → 6-deoxo-3-dehydroteasterone → 3-dehydroteasterone. 6-deoxoteasterone ↔ 6-deoxo-3-dehydroteasterone ↔ 6-deoxotyphasterol → 6-deoxocastasterone → castasterone. This shows that there are campestanol-dependent and campestanol-independent pathway in B. distachyon that synthesize 24-methylated brassinosteroids (BRs). Biochemical analysis of BRs biosynthetic enzymes confirmed that BdDET2, BdCYP90B1, BdCYP90A1, BdCYP90D2, and BdCYP85A1 are orthologous to BR 5α-reductase, BR C-22 hydroxylase, BR C-3 oxidase, BR C-23 hydroxylase, and BR C-6 oxidase, respectively. Brassinolide was not identified in B. distachyon. Additionally, B. distachyon crude enzyme solutions could not catalyze the conversion of castasterone to brassinolide, and the gene encoding an ortholog of CYP85A2 (a brassinolide synthase) was not found in B. distachyon. These results strongly suggest that the end product for brassinosteroid biosynthesis which controls the growth and development of B. distachyon is not brassinolide but rather castasterone.Brominated azo dyes (BADs) have been identified as predominant indoor brominated pollutants in daycare dust; thus, their potential health risk to children is of concern. However, the toxicities of BADs remain elusive. In this study, the toxicokinetics of two predominant BADs, Disperse Blue 373 (DB373) and Disperse Violet 93 (DV93), and their suspect metabolite 2-bromo-4,6-dinitroaniline (BDNA) was investigated in embryos of zebrafish (Danio rerio). The bioconcentration factor of DV93 at 120 hpf is 6.2-fold lower than that of DB373. The nontarget analysis revealed distinct metabolism routes between DB373 and DV93 by reducing nitro groups to nitroso (DB373) or amine (DV93), despite their similar structures. NAD(P)H quinone oxidoreductase 1 (NQO1) and pyruvate dehydrogenase were predicted as the enzymes responsible for the reduction of DB373 and DV93 by correlating time courses of the metabolites and enzyme development. Further in vitro recombinant enzyme and in vivo inhibition results validated NQO1 as the enzyme specifically reducing DB373, but not DV93. Global proteome profiling revealed that the expression levels of proteins from the "apoptosis-induced DNA fragmentation" pathway were significantly upregulated by all three BADs, supporting the bioactivation of BADs to mutagenic aromatic amines. This study discovered the bioactivation of BADs via distinct eukaryotic enzymes, implying their potential health risks.Matrix-assisted laser desorption ionization mass spectrometry imaging (MALDI-MSI) is widely used to visualize and analyze the distribution of membrane lipids in an increasingly large number of applications. https://www.selleckchem.com/products/Chlorogenic-acid.html In this context, different lipoforms of glycerophospholipids (GPLs) are among the prime targets of interest. For this group of analytes, however, ion suppression effects have been described to strongly favor the detection of certain GPL classes over others, thereby hampering the analysis of suppressed species and greatly restraining quantitative analysis. These effects are generally attributed to the distribution of available charge carriers during the MALDI process. Here, we present a systematic investigation of charge distribution between different classes of GPL under MALDI-MSI conditions. For this, we constructed arrays of artificial tissues with different formulated lipid composition that contained predefined amounts of only two specific GPL classes and analyzed them with MALDI-MSI in positive- and negative-ion modes. Next to a characterization of expected ion suppression effects, analysis of these binary systems revealed yet undescribed signal intensity enhancement for the combinations of certain GPL classes. Furthermore, the comprehensive data allowed us to compile a hierarchy of charge affinities for the investigated GPL classes in both polarities. Additional experiments revealed that laser post-ionization (MALDI-2) has great potential to overwrite changes in signal intensity caused by charge distribution among different GPL classes observed in standard MALDI-MSI.Functionalized gold nanoparticles are investigated by density functional theory calculations in the context of cancer radiotherapy. Several typical experimental shapes, including nanostars, nanospheres, and nanorods, are modeled by optimizing Au clusters covered by organic monolayers composed of hydrated short-chain polyethylene glycol (PEG) ligands. The PEGylation stabilizes significantly the stellation of decahedral Au54 by deforming significantly its geometry at the spikes. The higher stability of the PEG molecules adsorbed on this stellated nanocluster with respect to the more spherical icosahedral Au55 and truncated octahedral Au79 leads to a larger energy cost to desorb them and thus a weaker propensity for the starred nanoparticle to exchange ligands with the cell membrane, in agreement with experiments. These results open interesting possibilities for advancing our understanding of the cellular uptake of gold nanoparticles.The broad synthetic utility of organoboron compounds stems from their ready ability to undergo 1,2-migrations. Normally, such shifts are induced by α-leaving groups or by reactions of alkenyl boronates with electrophiles. Herein, we present a new strategy to induce 1,2-metalate rearrangements, via ring expansion of vinylcyclopropyl boronate complexes activated by electrophiles. This leads to a cyclopropane-stabilized carbocation, which triggers ring expansion and concomitant 1,2-metalate rearrangement. This novel process delivers medicinally relevant 1,2-substituted cyclobutyl boronic esters with high levels of diastereoselectivity. A wide range of organolithiums and Grignard reagents, electrophiles, and vinylcyclopropyl boronic esters can be used. The methodology was applied to a short, stereoselective synthesis of (±)-grandisol. Computational studies indicate that the reaction proceeds via a nonclassical carbocation followed by anti-1,2-migration.0 Comments 0 Shares 0 Views 0 Reviews -
The low yield strength (~300 MPa) of twinning-induced plasticity (TWIP) steels greatly limits their structural applications in the industrial field. Conventional strengthening mechanisms usually cause an enhancement of yield strength but also a severe loss of ductility. In this research, gradient substructures were introduced in the Fe-22Mn-0.6C TWIP steels by different pre-torsional deformation in order to overcome the above limitations. The substructure evolution, mechanical properties, and their origins in gradient-substructured (GS) TWIP steels were measured and compared by electron backscattered diffraction (EBSD), monotonous and loading-unloading-reloading (LUR) tensile tests. It was found that a simple torsional treatment could prepare gradient twins and dislocations in coarse-grained TWIP steel samples depending on torsional strain. The uniaxial tensile tests indicated that a superior combination of high yield strength, high ultimate strength, and considerable ductility was simultaneously obtained in the GS samples. The high yield strength and high ultimate tensile strength were attributed to synergetic strengthening mechanisms, viz., dislocation strengthening, due to the accumulation of high density of dislocations, and very high **** stress strengthening due to gradient substructure distribution, which was accommodated through pile-ups of extra geometrically necessary dislocations (GNDs) across the sample-scale. Additionally, high ductility originated from gradient substructure-induced **** stress hardening. The present study is also beneficial to the design efforts of high strength and high ductility of other heterogeneous-structured TWIP alloy systems.The quest and design of new brassinosteroids analogs is a matter of current interest. Herein, the effect of short alkyl side chains and the configuration at C22 on the growth-promoting activity of a series of new brassinosteroid 24-norcholan-type analogs have been evaluated by the rice leaf inclination test using brassinolide as positive control. The highest activities were found for triol 3 with a C22(S) configuration and monobenzoylated derivatives. A docking study of these compounds into the active site of the Brassinosteroid Insensitive 1(BRI1)-ligand-BRI1-Associated Receptor Kinase 1 (BAK1) complex was performed using AutoDock Vina, and protein-ligand contacts were analyzed using LigPlot+. The results suggest that the hydrophobic interactions of ligands with the receptor BRI1LRR and hydrogen bonding with BAK1 in the complex are important for ligand recognition. For monobenzoylated derivatives, the absence of the hydrophobic end in the alkyl chain seems to be compensated by the benzoyl group. Thus, it would be interesting to determine if this result depends on the nature of the substituent group. Finally, mixtures of S/R triols 3/4 exhibit activities that are comparable or even better than those found for brassinolide. Thus, these compounds are potential candidates for application in agriculture to improve the growth and yield of plants against various types of biotic and abiotic stress.The topic is how to achieve long-term protective anti-tumor immunity by anti-cancer vaccination and what are its mechanisms. Cancer vaccines should instruct the immune system regarding relevant cancer targets and contain signals for innate immunity activation. Of central importance is T-cell mediated immunity and thus a detailed understanding of cognate interactions between tumor antigen (TA)-specific T cells and TA-presenting dendritic cells. Microbes and their associated molecular patterns initiate early inflammatory defense reactions that can contribute to the activation of antigen-presenting cells (APCs) and to costimulation of T cells. The concommitant stimulation of naive TA-specific CD4+ and CD8+ T cells with TAs and costimulatory signals occurs in T-APC clusters that generate effectors, such as cytotoxic T lymphocytes and T cell mediated immunological memory. Information about how such memory can be maintained over long times is updated. The role that the bone marrow with its specialized niches plays for the survival of memory T cells is emphasized. Examples are presented that demonstrate long-term protective anti-tumor immunity can be achieved by post-operative vaccination with autologous cancer vaccines that are modified by virus infection.Venous thromboembolism (VTE) is frequent among patients with cancer. Ambulatory cancer patients starting chemotherapy have a 5% to 10% risk of cancer associated thrombosis (CAT) within the first year after cancer diagnosis. This risk may vary according to patient characteristics, cancer location, cancer stage, or the type of chemotherapeutic regimen. Landmark studies evaluating thrombophrophylaxis with low molecular weight heparin (LMWH) for ambulatory cancer patients have shown a relative reduction in the rate of symptomatic VTE of about one half. However, the absolute risk reduction is modest among unselected patients given a rather low risk of events resulting in a number needed to treat (NNT) of 40 to 50. Moreover, this modest benefit is mitigated by a trend towards an increased risk of bleeding, and the economic and patient burden due to daily injections of LMWH. For these reasons, routine thromboprophylaxis is not recommended by expert societies. Advances in VTE risk stratification among cancer patients, and growing evidence regarding efficacy and safety of direct oral anticoagulants (DOACs) for the treatment and prevention of CAT have led to reconsider the paradigms of this risk-benefit assessment. https://www.selleckchem.com/products/cnqx.html This narrative review aims to summarize the recent evidence provided by randomized trials comparing DOACs to placebo in ambulatory cancer patients and its impact on expert recommendations and clinical practice.In this paper, a self-healable nanocomposite based on the Diels-Alder reaction is developed. A graphene-based nanofiller is introduced to improve the self-healing efficiency, as well as the mechanical properties of the nanocomposite. Graphene oxide (GO) is modified with maleimide functional groups, and the maleimide-modified GO (mGO) enhanced the compatibility of the polymer matrix and nanofiller. The tensile strength of the nanocomposite containing 0.030 wt% mGO is improved by 172%, compared to that of a polymer film incorporating both furan-functionalized polymer and bismaleimide without any nanofiller. Moreover, maleimide groups of the surface on mGO participate in the Diels-Alder reaction, which improves the self-healing efficiency. The mechanical and self-healing properties are significantly improved by using a small amount of mGO.
The low yield strength (~300 MPa) of twinning-induced plasticity (TWIP) steels greatly limits their structural applications in the industrial field. Conventional strengthening mechanisms usually cause an enhancement of yield strength but also a severe loss of ductility. In this research, gradient substructures were introduced in the Fe-22Mn-0.6C TWIP steels by different pre-torsional deformation in order to overcome the above limitations. The substructure evolution, mechanical properties, and their origins in gradient-substructured (GS) TWIP steels were measured and compared by electron backscattered diffraction (EBSD), monotonous and loading-unloading-reloading (LUR) tensile tests. It was found that a simple torsional treatment could prepare gradient twins and dislocations in coarse-grained TWIP steel samples depending on torsional strain. The uniaxial tensile tests indicated that a superior combination of high yield strength, high ultimate strength, and considerable ductility was simultaneously obtained in the GS samples. The high yield strength and high ultimate tensile strength were attributed to synergetic strengthening mechanisms, viz., dislocation strengthening, due to the accumulation of high density of dislocations, and very high back stress strengthening due to gradient substructure distribution, which was accommodated through pile-ups of extra geometrically necessary dislocations (GNDs) across the sample-scale. Additionally, high ductility originated from gradient substructure-induced back stress hardening. The present study is also beneficial to the design efforts of high strength and high ductility of other heterogeneous-structured TWIP alloy systems.The quest and design of new brassinosteroids analogs is a matter of current interest. Herein, the effect of short alkyl side chains and the configuration at C22 on the growth-promoting activity of a series of new brassinosteroid 24-norcholan-type analogs have been evaluated by the rice leaf inclination test using brassinolide as positive control. The highest activities were found for triol 3 with a C22(S) configuration and monobenzoylated derivatives. A docking study of these compounds into the active site of the Brassinosteroid Insensitive 1(BRI1)-ligand-BRI1-Associated Receptor Kinase 1 (BAK1) complex was performed using AutoDock Vina, and protein-ligand contacts were analyzed using LigPlot+. The results suggest that the hydrophobic interactions of ligands with the receptor BRI1LRR and hydrogen bonding with BAK1 in the complex are important for ligand recognition. For monobenzoylated derivatives, the absence of the hydrophobic end in the alkyl chain seems to be compensated by the benzoyl group. Thus, it would be interesting to determine if this result depends on the nature of the substituent group. Finally, mixtures of S/R triols 3/4 exhibit activities that are comparable or even better than those found for brassinolide. Thus, these compounds are potential candidates for application in agriculture to improve the growth and yield of plants against various types of biotic and abiotic stress.The topic is how to achieve long-term protective anti-tumor immunity by anti-cancer vaccination and what are its mechanisms. Cancer vaccines should instruct the immune system regarding relevant cancer targets and contain signals for innate immunity activation. Of central importance is T-cell mediated immunity and thus a detailed understanding of cognate interactions between tumor antigen (TA)-specific T cells and TA-presenting dendritic cells. Microbes and their associated molecular patterns initiate early inflammatory defense reactions that can contribute to the activation of antigen-presenting cells (APCs) and to costimulation of T cells. The concommitant stimulation of naive TA-specific CD4+ and CD8+ T cells with TAs and costimulatory signals occurs in T-APC clusters that generate effectors, such as cytotoxic T lymphocytes and T cell mediated immunological memory. Information about how such memory can be maintained over long times is updated. The role that the bone marrow with its specialized niches plays for the survival of memory T cells is emphasized. Examples are presented that demonstrate long-term protective anti-tumor immunity can be achieved by post-operative vaccination with autologous cancer vaccines that are modified by virus infection.Venous thromboembolism (VTE) is frequent among patients with cancer. Ambulatory cancer patients starting chemotherapy have a 5% to 10% risk of cancer associated thrombosis (CAT) within the first year after cancer diagnosis. This risk may vary according to patient characteristics, cancer location, cancer stage, or the type of chemotherapeutic regimen. Landmark studies evaluating thrombophrophylaxis with low molecular weight heparin (LMWH) for ambulatory cancer patients have shown a relative reduction in the rate of symptomatic VTE of about one half. However, the absolute risk reduction is modest among unselected patients given a rather low risk of events resulting in a number needed to treat (NNT) of 40 to 50. Moreover, this modest benefit is mitigated by a trend towards an increased risk of bleeding, and the economic and patient burden due to daily injections of LMWH. For these reasons, routine thromboprophylaxis is not recommended by expert societies. Advances in VTE risk stratification among cancer patients, and growing evidence regarding efficacy and safety of direct oral anticoagulants (DOACs) for the treatment and prevention of CAT have led to reconsider the paradigms of this risk-benefit assessment. https://www.selleckchem.com/products/cnqx.html This narrative review aims to summarize the recent evidence provided by randomized trials comparing DOACs to placebo in ambulatory cancer patients and its impact on expert recommendations and clinical practice.In this paper, a self-healable nanocomposite based on the Diels-Alder reaction is developed. A graphene-based nanofiller is introduced to improve the self-healing efficiency, as well as the mechanical properties of the nanocomposite. Graphene oxide (GO) is modified with maleimide functional groups, and the maleimide-modified GO (mGO) enhanced the compatibility of the polymer matrix and nanofiller. The tensile strength of the nanocomposite containing 0.030 wt% mGO is improved by 172%, compared to that of a polymer film incorporating both furan-functionalized polymer and bismaleimide without any nanofiller. Moreover, maleimide groups of the surface on mGO participate in the Diels-Alder reaction, which improves the self-healing efficiency. The mechanical and self-healing properties are significantly improved by using a small amount of mGO.0 Comments 0 Shares 0 Views 0 Reviews -
She was found to have a Masaoka stage III World Health Organization (WHO) type B3 thymic endothelial neoplasm and underwent surgical resection.Cirrhosis and its associated complications such, as variceal bleeding, are rare in children, carrying significant morbidity and mortality. Leading causes of cirrhosis in the pediatric population include infection, neoplasm, and metabolic and genetic disorders, which is in contrast to the adult population. Acute gastrointestinal bleeding, as seen with variceal bleeding, has been previously associated with diabetic ketoacidosis through a multifactorial relationship. https://www.selleckchem.com/products/epibrassinolide.html The case was complicated by hypovolemic shock whose resuscitation and subsequent transfusion was associated with cardiac overload. We highlight the need for balanced, judicious resuscitation in these individuals as well as the need for heightened awareness of coexisting pathologies such as diabetic ketoacidosis.Gastric volvulus is a rare but potentially life-threatening condition, with difficult diagnosis. We present a case report of a demented woman aged 65 years that attended the emergency department with epigastric pain and vomiting for the past 10 days. The chest plain revealed a retrocardiac air-filled mass and the abdomino-pelvic computed tomography confirmed the diagnosis of gastric volvulus. The patient was admitted. A nasogastric tube was introduced, antibiotics and parenteric nutrition were started and the patient didn't eat anything. The patient was operated at fifth day of admission by laparoscopy. There weren't signs of gastric necrosis, so the stomach was mobilized for its natural position on abdominal cavity, the hiatal defect was closed and a Nissen fundoplicature was performed. The post operative period was uneventful and the patient was discharged on the third post-operative day, without any complication. This case illustrates a sub acute presentation form of gastric volvulus and a differed minimally invasive approach attending at the patient's clinical stability.Radiation-induced rib fractures (RIRF) are long-term complications associated with irradiation of the chest/chest wall. RIRFs are commonly seen in lung- or breast-cancer patients treated with stereotactic body radiotherapy (SBRT) or conventional external beam radiation therapy (EBRT), respectively. We report a case of a 31-year-old female presenting with pathological fractures of the third, fourth, and fifth ribs discovered on magnetic resonance imaging (MRI) as a complication from pencil beam scanning (PBS) proton therapy (PT), of the whole left breast and regional lymph nodes. To our knowledge, this presentation is the first to be initially reported on MRI in radiological literature.We present a case of central diabetes insipidus (DI) secondary to neurosarcoidosis. The path to final diagnosis was challenging. Along with reporting the case, we review the available medical literature relating to neurosarcoidosis and central diabetes insipidus in this case report. Patient is a 56-year-old female with notable history of rheumatoid arthritis, anxiety, asthma, hypertension, spinal stenosis, and seizures of unknown etiology who presented to the emergency department for worsening headache for one week. She also endorsed decreased vision, photophobia, nausea, vomiting, gait abnormality, polyuria, and polydipsia over the past three months. Physical exam and neurological exam were unremarkable. Labs on presentation were notable for hypernatremia, increased serum osmolality and urine output of 5 L/day. Given her persistent headache and history of seizure, she underwent a CT head without contrast which showed a posterior suprasellar soft tissue fullness measuring 6 mm in the hypothalamic region. She s started on desmopressin 50 mg twice a day which resulted in marked improvement in urine output, serum sodium, and osmolality. Although it is rare to have nervous system involvement of sarcoidosis, symptoms of central diabetes insipidus could represent the first clinical manifestations of neurosarcoidosis. Proper treatment should be initiated in a timely fashion to avoid complications such as hydrocephalus.Usher syndrome type I is a rare genetic autosomal recessive disease caused by mutations in specific genes that provide instructions for making proteins involved in normal hearing, vision, and balance. It is characterized by hearing impairment due to the inability of auditory nerves to send sensory input to the brain leading to hearing loss along with retinitis pigmentosa (RP), which is a progressive, bilateral, symmetrical retinal degeneration involving photoreceptor cells. We report a 32-year-old male patient who presented to us with complaints of night blindness and progressive vision loss for the past 20 years. He had bilateral hearing loss leading to deaf-mutism. In addition, his developmental milestones were delayed. His fundoscopic findings were consistent with RP and his electroretinography confirmed reduced retinal activity. Pure tone audiometry confirmed bilateral sensory neural hearing. His mother was a known case of Usher syndrome type 1. His family history was remarkable for multiple consanguineous marriages in both his parental and maternal families and a confirmed diagnosis of Usher syndrome in paternal uncle. The patient was tried on hearing aids and vitamin A medication but with minimal improvement in his overall condition. A multidisciplinary approach, involving an audiologist, speech, and language therapist was adapted to help the patient. Early genetic testing can help diagnose such cases in its early stages and genetic counseling regarding the detrimental effects of consanguineous marriages can play a very positive role in genetic diseases, especially those with autosomal recessive inheritance patterns.Our case highlights a patient with spontaneous retroperitoneal hematoma without clear cause in the setting of myasthenic crisis. While myasthenia gravis (MG) has been reported in the literature to be associated with vascular pathology such as polyarteritis nodosa, its association with coagulopathy and spontaneous major bleed is currently unclear. The patient in this case developed a sudden unprovoked iliopsoas hematoma while in the ICU for the management of newly diagnosed MG. Acute anemia was the only clinical sign which was later confirmed by imaging findings.
She was found to have a Masaoka stage III World Health Organization (WHO) type B3 thymic endothelial neoplasm and underwent surgical resection.Cirrhosis and its associated complications such, as variceal bleeding, are rare in children, carrying significant morbidity and mortality. Leading causes of cirrhosis in the pediatric population include infection, neoplasm, and metabolic and genetic disorders, which is in contrast to the adult population. Acute gastrointestinal bleeding, as seen with variceal bleeding, has been previously associated with diabetic ketoacidosis through a multifactorial relationship. https://www.selleckchem.com/products/epibrassinolide.html The case was complicated by hypovolemic shock whose resuscitation and subsequent transfusion was associated with cardiac overload. We highlight the need for balanced, judicious resuscitation in these individuals as well as the need for heightened awareness of coexisting pathologies such as diabetic ketoacidosis.Gastric volvulus is a rare but potentially life-threatening condition, with difficult diagnosis. We present a case report of a demented woman aged 65 years that attended the emergency department with epigastric pain and vomiting for the past 10 days. The chest plain revealed a retrocardiac air-filled mass and the abdomino-pelvic computed tomography confirmed the diagnosis of gastric volvulus. The patient was admitted. A nasogastric tube was introduced, antibiotics and parenteric nutrition were started and the patient didn't eat anything. The patient was operated at fifth day of admission by laparoscopy. There weren't signs of gastric necrosis, so the stomach was mobilized for its natural position on abdominal cavity, the hiatal defect was closed and a Nissen fundoplicature was performed. The post operative period was uneventful and the patient was discharged on the third post-operative day, without any complication. This case illustrates a sub acute presentation form of gastric volvulus and a differed minimally invasive approach attending at the patient's clinical stability.Radiation-induced rib fractures (RIRF) are long-term complications associated with irradiation of the chest/chest wall. RIRFs are commonly seen in lung- or breast-cancer patients treated with stereotactic body radiotherapy (SBRT) or conventional external beam radiation therapy (EBRT), respectively. We report a case of a 31-year-old female presenting with pathological fractures of the third, fourth, and fifth ribs discovered on magnetic resonance imaging (MRI) as a complication from pencil beam scanning (PBS) proton therapy (PT), of the whole left breast and regional lymph nodes. To our knowledge, this presentation is the first to be initially reported on MRI in radiological literature.We present a case of central diabetes insipidus (DI) secondary to neurosarcoidosis. The path to final diagnosis was challenging. Along with reporting the case, we review the available medical literature relating to neurosarcoidosis and central diabetes insipidus in this case report. Patient is a 56-year-old female with notable history of rheumatoid arthritis, anxiety, asthma, hypertension, spinal stenosis, and seizures of unknown etiology who presented to the emergency department for worsening headache for one week. She also endorsed decreased vision, photophobia, nausea, vomiting, gait abnormality, polyuria, and polydipsia over the past three months. Physical exam and neurological exam were unremarkable. Labs on presentation were notable for hypernatremia, increased serum osmolality and urine output of 5 L/day. Given her persistent headache and history of seizure, she underwent a CT head without contrast which showed a posterior suprasellar soft tissue fullness measuring 6 mm in the hypothalamic region. She s started on desmopressin 50 mg twice a day which resulted in marked improvement in urine output, serum sodium, and osmolality. Although it is rare to have nervous system involvement of sarcoidosis, symptoms of central diabetes insipidus could represent the first clinical manifestations of neurosarcoidosis. Proper treatment should be initiated in a timely fashion to avoid complications such as hydrocephalus.Usher syndrome type I is a rare genetic autosomal recessive disease caused by mutations in specific genes that provide instructions for making proteins involved in normal hearing, vision, and balance. It is characterized by hearing impairment due to the inability of auditory nerves to send sensory input to the brain leading to hearing loss along with retinitis pigmentosa (RP), which is a progressive, bilateral, symmetrical retinal degeneration involving photoreceptor cells. We report a 32-year-old male patient who presented to us with complaints of night blindness and progressive vision loss for the past 20 years. He had bilateral hearing loss leading to deaf-mutism. In addition, his developmental milestones were delayed. His fundoscopic findings were consistent with RP and his electroretinography confirmed reduced retinal activity. Pure tone audiometry confirmed bilateral sensory neural hearing. His mother was a known case of Usher syndrome type 1. His family history was remarkable for multiple consanguineous marriages in both his parental and maternal families and a confirmed diagnosis of Usher syndrome in paternal uncle. The patient was tried on hearing aids and vitamin A medication but with minimal improvement in his overall condition. A multidisciplinary approach, involving an audiologist, speech, and language therapist was adapted to help the patient. Early genetic testing can help diagnose such cases in its early stages and genetic counseling regarding the detrimental effects of consanguineous marriages can play a very positive role in genetic diseases, especially those with autosomal recessive inheritance patterns.Our case highlights a patient with spontaneous retroperitoneal hematoma without clear cause in the setting of myasthenic crisis. While myasthenia gravis (MG) has been reported in the literature to be associated with vascular pathology such as polyarteritis nodosa, its association with coagulopathy and spontaneous major bleed is currently unclear. The patient in this case developed a sudden unprovoked iliopsoas hematoma while in the ICU for the management of newly diagnosed MG. Acute anemia was the only clinical sign which was later confirmed by imaging findings.0 Comments 0 Shares 0 Views 0 Reviews -
Objective Excessive daytime sleepiness is a frequently described phenomenon in pregnant women. The Epworth Sleepiness Scale (ESS) is a self reported standardized method of assessing sleep propensity and has been used extensively within pregnant populations. An elevated score is associated with sleep disordered breathing, as well as adverse obstetric and neonatal outcomes which may be indicative of a degree of placental dysfunction. Thus the aim of this study was to prospectively assess women using the Epworth questionnaire in conjunction with an ultrasound in both the second and third trimesters to determine if there was a difference in ESS scores across gestation and if a mid or late gestation assessment was correlated with Doppler ultrasound measures of fetal well-being.Materials and methods Participants were prospectively recruited from a tertiary obstetric hospital and completed both an Epworth questionnaire and ultrasound examination in the second and third trimesters.Results A total of 302 women took part in this cohort study. There was a statistically significant (p = .02) increase in ESS score across gestation. https://www.selleckchem.com/products/Chlorogenic-acid.html There was however no correlation identified in either the second or third trimester between ESS score and umbilical artery pulsatility index, middle cerebral artery pulsatility index, cerebroplacental ratio, umbilical venous flow, uterine artery pulsatility index or estimated fetal weight. A higher birth weight is associated with a higher ESS score in the second trimester but not in the third trimester (p = .03).Conclusions Maternal sleep disordered breathing assessed by the ESS score is only correlated with increased birth weight but not with fetal Doppler parameters in low risk pregnancies.Obstetric physiology may alter lactate metabolism and affect the ability to use lactate as a discriminator of critical illness in pregnancy. This prospective, cross-sectional study describes venous lactate levels in women presenting for acute care during pregnancy as well as characteristics associated with elevated lactate. Obstetric patients >20-week gestation presenting for acute evaluation were included and a venous lactate sample was drawn for each patient. Elevated lactate was defined as ≥2 mmol/L. One hundred two women were enrolled and venous lactate samples were obtained for 100 participants. Median lactate level was 1.22 (IQR 0.95-1.49) and 86% of patients had normal lactate. Six patients presented with infectious complaints, none of whom had sepsis or elevated lactate. Of the 14 patients with elevated lactate, all presented with labor complaints and 10 (71.4%) were admitted in labor. Elevated lactate level was significantly associated with labor complaints and admission in labor (p less then .01). Thus, lactate may not be able to discriminate severe infection consistently in pregnancy as it is confounded by labor. Further research is necessary to clarify how lactate may be used more effectively in pregnant patients and to identify alternate strategies for sepsis screening.Purpose To develop and characterize a tissue-mimicking phantom that enables the direct comparison of magnetic resonance (MR) and ultrasound (US) imaging techniques useful for monitoring high-intensity focused ultrasound (HIFU) treatments. With no additions, gelatin phantoms produce little if any scattering required for US imaging. This study characterizes the MR and US image characteristics as a function of psyllium husk concentration, which was added to increase US scattering.Methods Gelatin phantoms were constructed with varying concentrations of psyllium husk. The effects of psyllium husk concentration on US B-mode and MR imaging were evaluated at nine different concentrations. T1, T2, and T2* MR maps were acquired. Acoustic properties (attenuation and speed of sound) were measured at frequencies of 0.6, 1.0, 1.8, and 3.0 MHz using a through-transmission technique. Phantom elastic properties were evaluated for both time and temperature dependence.Results Ultrasound image echogenicity increased with increasing psyllium husk concentration while quality of gradient-recalled echo MR images decreased with increasing concentration. For all phantoms, the measured speed of sound ranged between 1567-1569 m/s and the attenuation ranged between 0.42-0.44 dB/(cm·MHz). Measured T1 ranged from 974-1051 ms. The T2 and T2* values ranged from 97-108 ms and 48-88 ms, respectively, with both showing a decreasing trend with increased psyllium husk concentration. Phantom stiffness, measured using US shear-wave speed measurements, increased with age and decreased with increasing temperature.Conclusions The presented dual-use tissue-mimicking phantom is easy to manufacture and can be used to compare and evaluate US-guided and MR-guided HIFU imaging protocols.Superficial angiomyxoma is a rare, benign, multilobulated cutaneous tumor composed of stellate and spindle cells, a prominent myxoid matrix, and numerous blood vessels. Superficial angiomyxoma may be indistinguishable from cutaneous lesions of the Carney complex, although superficial angiomyxoma can occur independently of the complex. In this article, we present the case of a 39-year-old Japanese woman with a 40 × 30 mm, focally ulcerated, polypoid superficial angiomyxoma on the left nipple without any evidence of Carney complex. The development of superficial angiomyxoma on the nipples in a patient without the Carney complex is extremely rare. Indeed, only 3 cases of superficial angiomyxoma arising on the nipple have been reported to date, and this is the first such report in Japan. In such cases, the majority of superficial angiomyxoma of the nipples develop in premenopausal women. The possibility of superficial angiomyxoma should be considered for all polypoid nipple lesion, particularly in premenopausal women, and complete excision with follow-up observation should be performed.Diabetic foot is a serious problem for health care systems. Twitter can provide communication between people and it might be an informative tool for health care management. The purpose of this study is detecting the people or organizations that tweet about diabetic foot and analyze the interactions of these tweets on Twitter. All tweets containing the keyword "diabetic foot" in April 2019 were collected. The users were separated into 7 groups patients with diabetes, health care providers, nongovernmental organizations, information sites and communication media, private companies, medical students, and others. Health care professionals and nonprofessionals were evaluated in likes, mentions, and retweets. The major group was health care providers. By 2-group comparisons of professionals and nonprofessionals, all likes, mentions, and retweets were significantly different (P = .02, P = .04, P less then .001, respectively). We concluded that the tweets of health care professionals get more interaction than others.
Objective Excessive daytime sleepiness is a frequently described phenomenon in pregnant women. The Epworth Sleepiness Scale (ESS) is a self reported standardized method of assessing sleep propensity and has been used extensively within pregnant populations. An elevated score is associated with sleep disordered breathing, as well as adverse obstetric and neonatal outcomes which may be indicative of a degree of placental dysfunction. Thus the aim of this study was to prospectively assess women using the Epworth questionnaire in conjunction with an ultrasound in both the second and third trimesters to determine if there was a difference in ESS scores across gestation and if a mid or late gestation assessment was correlated with Doppler ultrasound measures of fetal well-being.Materials and methods Participants were prospectively recruited from a tertiary obstetric hospital and completed both an Epworth questionnaire and ultrasound examination in the second and third trimesters.Results A total of 302 women took part in this cohort study. There was a statistically significant (p = .02) increase in ESS score across gestation. https://www.selleckchem.com/products/Chlorogenic-acid.html There was however no correlation identified in either the second or third trimester between ESS score and umbilical artery pulsatility index, middle cerebral artery pulsatility index, cerebroplacental ratio, umbilical venous flow, uterine artery pulsatility index or estimated fetal weight. A higher birth weight is associated with a higher ESS score in the second trimester but not in the third trimester (p = .03).Conclusions Maternal sleep disordered breathing assessed by the ESS score is only correlated with increased birth weight but not with fetal Doppler parameters in low risk pregnancies.Obstetric physiology may alter lactate metabolism and affect the ability to use lactate as a discriminator of critical illness in pregnancy. This prospective, cross-sectional study describes venous lactate levels in women presenting for acute care during pregnancy as well as characteristics associated with elevated lactate. Obstetric patients >20-week gestation presenting for acute evaluation were included and a venous lactate sample was drawn for each patient. Elevated lactate was defined as ≥2 mmol/L. One hundred two women were enrolled and venous lactate samples were obtained for 100 participants. Median lactate level was 1.22 (IQR 0.95-1.49) and 86% of patients had normal lactate. Six patients presented with infectious complaints, none of whom had sepsis or elevated lactate. Of the 14 patients with elevated lactate, all presented with labor complaints and 10 (71.4%) were admitted in labor. Elevated lactate level was significantly associated with labor complaints and admission in labor (p less then .01). Thus, lactate may not be able to discriminate severe infection consistently in pregnancy as it is confounded by labor. Further research is necessary to clarify how lactate may be used more effectively in pregnant patients and to identify alternate strategies for sepsis screening.Purpose To develop and characterize a tissue-mimicking phantom that enables the direct comparison of magnetic resonance (MR) and ultrasound (US) imaging techniques useful for monitoring high-intensity focused ultrasound (HIFU) treatments. With no additions, gelatin phantoms produce little if any scattering required for US imaging. This study characterizes the MR and US image characteristics as a function of psyllium husk concentration, which was added to increase US scattering.Methods Gelatin phantoms were constructed with varying concentrations of psyllium husk. The effects of psyllium husk concentration on US B-mode and MR imaging were evaluated at nine different concentrations. T1, T2, and T2* MR maps were acquired. Acoustic properties (attenuation and speed of sound) were measured at frequencies of 0.6, 1.0, 1.8, and 3.0 MHz using a through-transmission technique. Phantom elastic properties were evaluated for both time and temperature dependence.Results Ultrasound image echogenicity increased with increasing psyllium husk concentration while quality of gradient-recalled echo MR images decreased with increasing concentration. For all phantoms, the measured speed of sound ranged between 1567-1569 m/s and the attenuation ranged between 0.42-0.44 dB/(cm·MHz). Measured T1 ranged from 974-1051 ms. The T2 and T2* values ranged from 97-108 ms and 48-88 ms, respectively, with both showing a decreasing trend with increased psyllium husk concentration. Phantom stiffness, measured using US shear-wave speed measurements, increased with age and decreased with increasing temperature.Conclusions The presented dual-use tissue-mimicking phantom is easy to manufacture and can be used to compare and evaluate US-guided and MR-guided HIFU imaging protocols.Superficial angiomyxoma is a rare, benign, multilobulated cutaneous tumor composed of stellate and spindle cells, a prominent myxoid matrix, and numerous blood vessels. Superficial angiomyxoma may be indistinguishable from cutaneous lesions of the Carney complex, although superficial angiomyxoma can occur independently of the complex. In this article, we present the case of a 39-year-old Japanese woman with a 40 × 30 mm, focally ulcerated, polypoid superficial angiomyxoma on the left nipple without any evidence of Carney complex. The development of superficial angiomyxoma on the nipples in a patient without the Carney complex is extremely rare. Indeed, only 3 cases of superficial angiomyxoma arising on the nipple have been reported to date, and this is the first such report in Japan. In such cases, the majority of superficial angiomyxoma of the nipples develop in premenopausal women. The possibility of superficial angiomyxoma should be considered for all polypoid nipple lesion, particularly in premenopausal women, and complete excision with follow-up observation should be performed.Diabetic foot is a serious problem for health care systems. Twitter can provide communication between people and it might be an informative tool for health care management. The purpose of this study is detecting the people or organizations that tweet about diabetic foot and analyze the interactions of these tweets on Twitter. All tweets containing the keyword "diabetic foot" in April 2019 were collected. The users were separated into 7 groups patients with diabetes, health care providers, nongovernmental organizations, information sites and communication media, private companies, medical students, and others. Health care professionals and nonprofessionals were evaluated in likes, mentions, and retweets. The major group was health care providers. By 2-group comparisons of professionals and nonprofessionals, all likes, mentions, and retweets were significantly different (P = .02, P = .04, P less then .001, respectively). We concluded that the tweets of health care professionals get more interaction than others.0 Comments 0 Shares 0 Views 0 Reviews -
errierenden Polgefäßes.OBJECTIVE The aim of this study is to assess the impact of a prolonged second stage of labor on maternal and neonatal outcomes by comparing women who had expectant management versus operative intervention beyond specified timeframes in the second stage of labor. STUDY DESIGN Retrospective cohort including live singletons at ≥36 weeks who reached the second stage of labor. Expectant management (second stage >3, 2, 2, and 1 hour in nulliparas with an epidural, nulliparas without an epidural, multiparas with an epidural, and multiparas without an epidural, respectively) was compared with those who had an operative delivery (vaginal or cesarean) prior to these timeframes. The primary maternal outcome was a composite of postpartum hemorrhage, chorioamnionitis, operative complications, postpartum infections, and intensive care unit admission. The primary neonatal outcome was a composite of cord blood acidemia, 5-minute Apgar's score 1 day. RESULTS Among 218 women, 115 (52.8%) had expectant management. Expectant management was associated with a significantly increased risk of the maternal composite (adjusted odds ratio [aOR] 1.99, 95% confidence interval [CI] 1.09-3.64) but not the neonatal composite (aOR 1.54, 95% CI 0.71-3.35). CONCLUSION Expectant management of a prolonged second stage was associated with a higher rate of adverse maternal outcomes, but the rate of adverse neonatal outcomes was not significantly increased. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.OBJECTIVE The aim of this study is to determine patterns of neurally adjusted ventilatory assist (NAVA) use in ventilator-dependent preterm infants with evolving or established severe bronchopulmonary dysplasia (sBPD) among centers of the BPD Collaborative, including indications for its initiation, discontinuation, and outcomes. STUDY DESIGN Retrospective review of infants with developing or established sBPD who were placed on NAVA after ≥4 weeks of mechanical ventilation and were ≥ 30 weeks of postmenstrual age (PMA). RESULTS Among the 13 sites of the BPD collaborative, only four centers (31%) used NAVA in the management of infants with evolving or established BPD. A total of 112 patients met inclusion criteria from these four centers. PMA, weight at the start of NAVA and median number of days on NAVA, were different among the four centers. The impact of NAVA therapy was assessed as being successful in 67% of infants, as defined by the ability to achieve respiratory stability at a lower level of ventilator support, including extubation to noninvasive positive pressure ventilation or support with a home ventilator. In total 87% (range 78-100%) of patients survived until discharge. CONCLUSION We conclude that NAVA can be used safely and effectively in selective infants with sBPD. Indications and current strategies for the application of NAVA in infants with evolving or established BPD, however, are highly variable between centers. Although this pilot study suggests that NAVA may be successfully used for the management of infants with BPD, sufficient experience and well-designed clinical studies are needed to establish standards of care for defining the role of NAVA in the care of infants with sBPD. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.BACKGROUND Gastroesophageal reflux disease (GERD) is an important concern after peroral endoscopic myotomy (POEM). However, there are limited data on the risk factors for post-POEM GERD and its responsiveness to proton pump inhibitors (PPIs). https://www.selleckchem.com/products/dibutyryl-camp-bucladesine.html In this study, we aimed to analyze the variables affecting the occurrence of GERD and its response to PPI therapy. METHODS Consecutive patients with idiopathic achalasia who underwent POEM (December 2016 to January 2018) were evaluated for GERD using 24-hour pH impedance, esophagogastroduodenoscopy (EGD), and symptoms. Multivariate analysis was performed to identify the variables affecting the incidence of post-POEM GERD. RESULTS A total of 209 patients with esophageal motility disorders, including 194 patients with non-sigmoid achalasia, underwent POEM during the study period. Comprehensive evaluation of GERD was completed on 167 patients (86.1 %) 47.3 % women with a mean (standard deviation) age of 41 (14.42) years and body mass index of 22.2 (3.89) kg/m2; the majority (70.7 %) were treatment naïve. A high DeMeester score (> 14.72), reflux esophagitis, and symptomatic GERD were identified in 47.9 %, 41.9 %, and 29.3 % of patients, respectively. On logistic regression analysis, type of achalasia, technique of POEM (anterior vs. posterior), pre- or post-POEM esophageal manometry variables, and patient characteristics were not associated with post-POEM GERD. Erosive esophagitis responded to PPI therapy in the majority of patients (81.4 %). CONCLUSION The incidence of GERD is high after POEM. Most of the reflux esophagitis is mild and responsive to PPI therapy. There are no procedural or patient-related variables that appear to affect the incidence of post-POEM GERD. © Georg Thieme Verlag KG Stuttgart · New York.BACKGROUND The effectiveness of endobiliary radiofrequency ablation (RFA) is still uncertain, especially in patients with malignant hilar biliary obstruction (MHBO). We examined the efficacy of endobiliary RFA followed by bilateral self-expandable metal stent (SEMS) placement for unresectable MHBO. METHODS 41 patients met the eligibility criteria for study inclusion. We evaluated the technical success, functional success, and recurrent biliary obstruction (RBO) associated with RFA with bilateral SEMS placement. RESULTS The technical and functional success rates were both 95.1 % (39/41). The RBO rate was 38.5 % (15/39), and the median time to RBO was 230 days. Stricture length was positively correlated with time to RBO in the multivariate analysis (P = 0.03). The median time to RBO was significantly longer in patients with strictures > 15 mm in length than in those with strictures ≤ 15 mm (314 vs. 156 days; P = 0.02). CONCLUSIONS The present study showed that endobiliary RFA with bilateral SEMS placement achieved good results, but selection of patients with an appropriate stricture length may be needed to obtain a sufficient ablative effect.
errierenden Polgefäßes.OBJECTIVE The aim of this study is to assess the impact of a prolonged second stage of labor on maternal and neonatal outcomes by comparing women who had expectant management versus operative intervention beyond specified timeframes in the second stage of labor. STUDY DESIGN Retrospective cohort including live singletons at ≥36 weeks who reached the second stage of labor. Expectant management (second stage >3, 2, 2, and 1 hour in nulliparas with an epidural, nulliparas without an epidural, multiparas with an epidural, and multiparas without an epidural, respectively) was compared with those who had an operative delivery (vaginal or cesarean) prior to these timeframes. The primary maternal outcome was a composite of postpartum hemorrhage, chorioamnionitis, operative complications, postpartum infections, and intensive care unit admission. The primary neonatal outcome was a composite of cord blood acidemia, 5-minute Apgar's score 1 day. RESULTS Among 218 women, 115 (52.8%) had expectant management. Expectant management was associated with a significantly increased risk of the maternal composite (adjusted odds ratio [aOR] 1.99, 95% confidence interval [CI] 1.09-3.64) but not the neonatal composite (aOR 1.54, 95% CI 0.71-3.35). CONCLUSION Expectant management of a prolonged second stage was associated with a higher rate of adverse maternal outcomes, but the rate of adverse neonatal outcomes was not significantly increased. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.OBJECTIVE The aim of this study is to determine patterns of neurally adjusted ventilatory assist (NAVA) use in ventilator-dependent preterm infants with evolving or established severe bronchopulmonary dysplasia (sBPD) among centers of the BPD Collaborative, including indications for its initiation, discontinuation, and outcomes. STUDY DESIGN Retrospective review of infants with developing or established sBPD who were placed on NAVA after ≥4 weeks of mechanical ventilation and were ≥ 30 weeks of postmenstrual age (PMA). RESULTS Among the 13 sites of the BPD collaborative, only four centers (31%) used NAVA in the management of infants with evolving or established BPD. A total of 112 patients met inclusion criteria from these four centers. PMA, weight at the start of NAVA and median number of days on NAVA, were different among the four centers. The impact of NAVA therapy was assessed as being successful in 67% of infants, as defined by the ability to achieve respiratory stability at a lower level of ventilator support, including extubation to noninvasive positive pressure ventilation or support with a home ventilator. In total 87% (range 78-100%) of patients survived until discharge. CONCLUSION We conclude that NAVA can be used safely and effectively in selective infants with sBPD. Indications and current strategies for the application of NAVA in infants with evolving or established BPD, however, are highly variable between centers. Although this pilot study suggests that NAVA may be successfully used for the management of infants with BPD, sufficient experience and well-designed clinical studies are needed to establish standards of care for defining the role of NAVA in the care of infants with sBPD. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.BACKGROUND Gastroesophageal reflux disease (GERD) is an important concern after peroral endoscopic myotomy (POEM). However, there are limited data on the risk factors for post-POEM GERD and its responsiveness to proton pump inhibitors (PPIs). https://www.selleckchem.com/products/dibutyryl-camp-bucladesine.html In this study, we aimed to analyze the variables affecting the occurrence of GERD and its response to PPI therapy. METHODS Consecutive patients with idiopathic achalasia who underwent POEM (December 2016 to January 2018) were evaluated for GERD using 24-hour pH impedance, esophagogastroduodenoscopy (EGD), and symptoms. Multivariate analysis was performed to identify the variables affecting the incidence of post-POEM GERD. RESULTS A total of 209 patients with esophageal motility disorders, including 194 patients with non-sigmoid achalasia, underwent POEM during the study period. Comprehensive evaluation of GERD was completed on 167 patients (86.1 %) 47.3 % women with a mean (standard deviation) age of 41 (14.42) years and body mass index of 22.2 (3.89) kg/m2; the majority (70.7 %) were treatment naïve. A high DeMeester score (> 14.72), reflux esophagitis, and symptomatic GERD were identified in 47.9 %, 41.9 %, and 29.3 % of patients, respectively. On logistic regression analysis, type of achalasia, technique of POEM (anterior vs. posterior), pre- or post-POEM esophageal manometry variables, and patient characteristics were not associated with post-POEM GERD. Erosive esophagitis responded to PPI therapy in the majority of patients (81.4 %). CONCLUSION The incidence of GERD is high after POEM. Most of the reflux esophagitis is mild and responsive to PPI therapy. There are no procedural or patient-related variables that appear to affect the incidence of post-POEM GERD. © Georg Thieme Verlag KG Stuttgart · New York.BACKGROUND The effectiveness of endobiliary radiofrequency ablation (RFA) is still uncertain, especially in patients with malignant hilar biliary obstruction (MHBO). We examined the efficacy of endobiliary RFA followed by bilateral self-expandable metal stent (SEMS) placement for unresectable MHBO. METHODS 41 patients met the eligibility criteria for study inclusion. We evaluated the technical success, functional success, and recurrent biliary obstruction (RBO) associated with RFA with bilateral SEMS placement. RESULTS The technical and functional success rates were both 95.1 % (39/41). The RBO rate was 38.5 % (15/39), and the median time to RBO was 230 days. Stricture length was positively correlated with time to RBO in the multivariate analysis (P = 0.03). The median time to RBO was significantly longer in patients with strictures > 15 mm in length than in those with strictures ≤ 15 mm (314 vs. 156 days; P = 0.02). CONCLUSIONS The present study showed that endobiliary RFA with bilateral SEMS placement achieved good results, but selection of patients with an appropriate stricture length may be needed to obtain a sufficient ablative effect.0 Comments 0 Shares 5 Views 0 Reviews -
Copyright 2020 Physicians Postgraduate Press, Inc.Prion real-time quaking-induced conversion (RT-QuIC) is an ultrasensitive assay detecting pathological aggregates of misfolded prion protein in biospecimens. We studied 71 punch biopsy skin samples of 35 patients with Creutzfeldt-Jakob disease (CJD), including five assessed in vitam. The results confirmed the high value of skin prion RT-QuIC for CJD diagnosis (89% sensitivity and 100% specificity) and support its use in clinical practice. Preliminary data based on a limited number of cases suggest that prion-seeding activity in the skin varies according to the prion strain, being higher in sporadic CJD subtypes linked to the V2 strain (VV2 and MV2K) than in typical CJDMM1. © 2020 The Authors. Annals of Clinical and Translational Neurology published by Wiley Periodicals, Inc on behalf of American Neurological Association.Diabetic retinopathy (DR) is one of the most severe clinical manifestations of diabetes mellitus and a major cause of blindness. DR is principally a microvascular disease, although the pathogenesis also involves metabolic reactive intermediates which induce neuronal and glial activation resulting in disruption of the neurovascular unit and regulation of the microvasculature. However, the impact of neural/glial activation in DR remains controversial, notwithstanding our understanding as to when neural/glial activation occurs in the course of disease. The objective of this study was to determine a potential protective role of neuropeptide Y (NPY) using an established model of DR permissive to N-methyl-D-aspartate (NMDA)-induced excitotoxic apoptosis of retinal ganglion cells (RGC) and vascular endothelial growth factor (VEGF)-induced vascular leakage. In vitro evaluation using primary retinal endothelial cells demonstrates that NPY promotes vascular integrity, demonstrated by maintained tight junction protein expression and reduced permeability in response to VEGF treatment. Furthermore, ex vivo assessment of retinal tissue explants shows that NPY can protect RGC from excitotoxic-induced apoptosis. In vivo clinical imaging and ex vivo tissue analysis in the diabetic model permitted assessment of NPY treatment in relation to neural and endothelial changes. The neuroprotective effects of NPY were confirmed by attenuating NMDA-induced retinal neural apoptosis and able to maintain inner retinal vascular integrity. These findings could have important clinical implications and offer novel therapeutic approaches for the treatment in the early stages of DR. © 2020 The Authors. Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.Over recent decades, gene therapy, which has enabled the treatment of several incurable diseases, has undergone a veritable revolution. Cell therapy has also seen major advances in the treatment of various diseases, particularly through the use of adult stem cells (ASCs). The combination of gene and cell therapy (GCT) has opened up new opportunities to improve advanced therapy medicinal products for the treatment of several diseases. Despite the considerable potential of GCT, the use of retroviral vectors has major limitations with regard to oncogene transactivation and the lack of physiological expression. Recently, gene therapists have focused on genome editing (GE) technologies as an alternative strategy. In this review, we discuss the potential benefits of using GE technologies to improve GCT approaches based on ASCs. We will begin with a brief summary of different GE platforms and techniques and will then focus on key therapeutic approaches that have been successfully used to treat diseases in animal models. Finally, we discuss whether ASC GE could become a real alternative to retroviral vectors in a GCT setting. https://www.selleckchem.com/products/PD-0332991.html © 2020 The Authors. STEM CELLS TRANSLATIONAL MEDICINE published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.Alcoholysis of CaMg2-based materials for hydrogen generation has been reported here. Hydrogen supply via the alcoholysis shows excellent outdoor application potential, which not only bypasses the formation of passivation layers but also breaks the temperature bottleneck. To remove the troublesome freezing issue of the water solution system in low-temperature, here, instead of pure methanol, methanol-water/ethanol solutions are applied to react with CaMg2 alloy and its hydrides for hydrogen generation. Compared with pure water and ethanol, the reaction of CaMg2-based materials with methanol possesses **** faster reaction kinetics and considerable hydrogen yield. The CaMg2 can generate 858 mL/g H2 within 3 min while it reacts vigorously with methanol, as opposed to low hydrogen yield with ethanol and water (395 and 224 mL/g H2 within 180 min, respectively) under same conditions. Even at -20 °C, there is still over 600 mL/g H 2 released at a conversion rate of 70.7% within 100 min for methanolysis, rendering it a prominent advantage for hydrogen production, especially in winter or subzero areas. Interestingly, the methanolysis by-products can transform into metal hydroxides and methanol while reacting with water, wherein methanol may be further separated and reused as an intermediate. Moreover, the hydrogen behaviors of CaMg2 methanolysis can be well-controlled by tailoring the component of solutions , delivering a promising hydrogen supply system for hydrogen economy. © 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.Three new iron(II)-benzilate complexes [(N4Py)FeII (benzilate)]ClO4 (1), [(N4PyMe2 )FeII (benzilate)]ClO4 (2) and [(N4PyMe4 )FeII (benzilate)]ClO4 (3) of neutral pentadentate nitrogen donor ligands have been isolated and characterized to study their dioxygen reactivity. Single-crystal X-ray structures reveal a mononuclear six-coordinate iron(II) center in each case, where benzilate binds to the iron center in monodentate mode via one carboxylate oxygen. Introduction of methyl groups in the 6-positions of the pyridine rings makes the N4PyMe2 and N4PyMe4 ligand fields weaker compared to that of the parent N4Py ligand. All the complexes (1-3) react with dioxygen to decarboxylate the coordinated benzilate to benzophenone quantitatively. The decarboxylation is faster for the complex of the more sterically hindered ligand and follows the order 3>2>1. The complexes display oxygen atom transfer reactivity to thioanisole and also exhibit hydrogen atom transfer reactions with substrates containing weak C-H bonds. Based on interception studies with external substrates, labelling experiments and Hammett analysis, a nucleophilic iron(II)-hydroperoxo species is proposed to form upon two-electron reductive activation of dioxygen by each iron(II)-benzilate complex.
Copyright 2020 Physicians Postgraduate Press, Inc.Prion real-time quaking-induced conversion (RT-QuIC) is an ultrasensitive assay detecting pathological aggregates of misfolded prion protein in biospecimens. We studied 71 punch biopsy skin samples of 35 patients with Creutzfeldt-Jakob disease (CJD), including five assessed in vitam. The results confirmed the high value of skin prion RT-QuIC for CJD diagnosis (89% sensitivity and 100% specificity) and support its use in clinical practice. Preliminary data based on a limited number of cases suggest that prion-seeding activity in the skin varies according to the prion strain, being higher in sporadic CJD subtypes linked to the V2 strain (VV2 and MV2K) than in typical CJDMM1. © 2020 The Authors. Annals of Clinical and Translational Neurology published by Wiley Periodicals, Inc on behalf of American Neurological Association.Diabetic retinopathy (DR) is one of the most severe clinical manifestations of diabetes mellitus and a major cause of blindness. DR is principally a microvascular disease, although the pathogenesis also involves metabolic reactive intermediates which induce neuronal and glial activation resulting in disruption of the neurovascular unit and regulation of the microvasculature. However, the impact of neural/glial activation in DR remains controversial, notwithstanding our understanding as to when neural/glial activation occurs in the course of disease. The objective of this study was to determine a potential protective role of neuropeptide Y (NPY) using an established model of DR permissive to N-methyl-D-aspartate (NMDA)-induced excitotoxic apoptosis of retinal ganglion cells (RGC) and vascular endothelial growth factor (VEGF)-induced vascular leakage. In vitro evaluation using primary retinal endothelial cells demonstrates that NPY promotes vascular integrity, demonstrated by maintained tight junction protein expression and reduced permeability in response to VEGF treatment. Furthermore, ex vivo assessment of retinal tissue explants shows that NPY can protect RGC from excitotoxic-induced apoptosis. In vivo clinical imaging and ex vivo tissue analysis in the diabetic model permitted assessment of NPY treatment in relation to neural and endothelial changes. The neuroprotective effects of NPY were confirmed by attenuating NMDA-induced retinal neural apoptosis and able to maintain inner retinal vascular integrity. These findings could have important clinical implications and offer novel therapeutic approaches for the treatment in the early stages of DR. © 2020 The Authors. Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.Over recent decades, gene therapy, which has enabled the treatment of several incurable diseases, has undergone a veritable revolution. Cell therapy has also seen major advances in the treatment of various diseases, particularly through the use of adult stem cells (ASCs). The combination of gene and cell therapy (GCT) has opened up new opportunities to improve advanced therapy medicinal products for the treatment of several diseases. Despite the considerable potential of GCT, the use of retroviral vectors has major limitations with regard to oncogene transactivation and the lack of physiological expression. Recently, gene therapists have focused on genome editing (GE) technologies as an alternative strategy. In this review, we discuss the potential benefits of using GE technologies to improve GCT approaches based on ASCs. We will begin with a brief summary of different GE platforms and techniques and will then focus on key therapeutic approaches that have been successfully used to treat diseases in animal models. Finally, we discuss whether ASC GE could become a real alternative to retroviral vectors in a GCT setting. https://www.selleckchem.com/products/PD-0332991.html © 2020 The Authors. STEM CELLS TRANSLATIONAL MEDICINE published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.Alcoholysis of CaMg2-based materials for hydrogen generation has been reported here. Hydrogen supply via the alcoholysis shows excellent outdoor application potential, which not only bypasses the formation of passivation layers but also breaks the temperature bottleneck. To remove the troublesome freezing issue of the water solution system in low-temperature, here, instead of pure methanol, methanol-water/ethanol solutions are applied to react with CaMg2 alloy and its hydrides for hydrogen generation. Compared with pure water and ethanol, the reaction of CaMg2-based materials with methanol possesses much faster reaction kinetics and considerable hydrogen yield. The CaMg2 can generate 858 mL/g H2 within 3 min while it reacts vigorously with methanol, as opposed to low hydrogen yield with ethanol and water (395 and 224 mL/g H2 within 180 min, respectively) under same conditions. Even at -20 °C, there is still over 600 mL/g H 2 released at a conversion rate of 70.7% within 100 min for methanolysis, rendering it a prominent advantage for hydrogen production, especially in winter or subzero areas. Interestingly, the methanolysis by-products can transform into metal hydroxides and methanol while reacting with water, wherein methanol may be further separated and reused as an intermediate. Moreover, the hydrogen behaviors of CaMg2 methanolysis can be well-controlled by tailoring the component of solutions , delivering a promising hydrogen supply system for hydrogen economy. © 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.Three new iron(II)-benzilate complexes [(N4Py)FeII (benzilate)]ClO4 (1), [(N4PyMe2 )FeII (benzilate)]ClO4 (2) and [(N4PyMe4 )FeII (benzilate)]ClO4 (3) of neutral pentadentate nitrogen donor ligands have been isolated and characterized to study their dioxygen reactivity. Single-crystal X-ray structures reveal a mononuclear six-coordinate iron(II) center in each case, where benzilate binds to the iron center in monodentate mode via one carboxylate oxygen. Introduction of methyl groups in the 6-positions of the pyridine rings makes the N4PyMe2 and N4PyMe4 ligand fields weaker compared to that of the parent N4Py ligand. All the complexes (1-3) react with dioxygen to decarboxylate the coordinated benzilate to benzophenone quantitatively. The decarboxylation is faster for the complex of the more sterically hindered ligand and follows the order 3>2>1. The complexes display oxygen atom transfer reactivity to thioanisole and also exhibit hydrogen atom transfer reactions with substrates containing weak C-H bonds. Based on interception studies with external substrates, labelling experiments and Hammett analysis, a nucleophilic iron(II)-hydroperoxo species is proposed to form upon two-electron reductive activation of dioxygen by each iron(II)-benzilate complex.0 Comments 0 Shares 15 Views 0 Reviews
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