CAO/R. Besides, this research provide some experimental foundation for search and determination of potential therapeutic targets of MCAO/R.The synthesis of purine conjugates with natural amino acids is one of the promising directions in search for novel therapeutic agents, including antimycobacterial agents. The purpose of this study was to synthesize N-(purin-6-yl)dipeptides containing the terminal fragment of (S)-glutamic acid. To obtain the target compounds, two synthetic routes were tested. The first of them is based on coupling of N-(purin-6-yl)-(S)-amino acids to dimethyl (S)-glutamate in the presence of carbodiimide coupling agent followed by the removal of ester groups. However, it turned out that this coupling process was accompanied by racemization of the chiral center of N-(purin-6-yl)-α-amino acids and in all cases led to mixtures of (S,S)- and (R,S)-diastereomers (64). Individual (S,S)-diastereomers were obtained using an alternative approach based on the nucleophilic substitution of chlorine in 6-chloropurine or 2-amino-6-chloropurine with corresponding dipeptides as nucleophiles. The enantiomeric purity of the target compounds was confirmed by chiral HPLC. To test the assumption that racemization of the chiral center of N-(purin-6-yl)-α-amino acids occurs with the participation of nitrogen atoms of the imidazole ring via the stage of formation of a chirally labile intermediate, we obtained such structural analogs of N-(purin-6-yl)-(S)-alanine as N-(9-benzylpurin-6-yl)-(S)-alanine and N-(7-deazapurin-6-yl)-(S)-alanine. It was found that coupling of these compounds to dimethyl (S)-glutamate was also accompanied by racemization. This indicates that the imidazole fragment does not play a crucial role in this process. When testing the antimycobacterial activity of some of the obtained compounds, conjugates with moderate activity against the laboratory Mycobacterium tuberculosis H37Rv strain (****3.1-6.25 μg/mL) were identified.Streptococcus pneumoniae (S. pneumoniae) is the main conditional pathogen of acute respiratory infection in infants, children, and older adults worldwide. https://www.selleckchem.com/products/ly2880070.html It was great significant to identify the epidemic characteristics of serotypes and antibiotic susceptibility for the prevention and treatment of S. pneumoniae diseases. This research assessed the serotype distribution and the minimum inhibitory concentrations (****) of S. pneumoniae isolated from pediatric patients to provide information on the epidemiology and antibiotic resistance of S. pneumoniae in Kunming, China. A total of 140 S. pneumoniae isolates were collected from pediatric patients at Kunming Children's Hospital from January 2016 to October 2017. Serotype identification was done by Quellung reaction and multiplex polymerase chain reaction. **** were determined by E-test. 140 isolates distributed in 13 types of serotypes. The top-three prevalent serotypes were 19F, 19A, and 6B. The immunization coverage rate of 13-valent pneumococcal conjugate vaccine (PCV) was relatively higher and should be introduced into the vaccination program in the region. MIC50 of penicillin, ceftriaxone, and levofloxacin was 1 μg/mL. MIC50 for meropenem and vancomycin was 0.38 μg/mL. MIC90 of penicillin, ceftriaxone, and levofloxacin was 1.5 μg/mL and that of meropenem and vancomycin was 0.5 μg/mL. The MIC90 of erythromycin was > 256 μg/mL. In summary, S. pneumoniae had low resistance rates to penicillin, ceftriaxone, levofloxacin, vancomycin, and meropenem, and these antibiotics could be the first-line agents for children with pneumococcal infections in Kunming.Two novel Alcanivorax-related strains, designated ST75FaO-1T and 521-1, were isolated from the seawater of the South China Sea and the deep-sea sediment of the West Pacific Ocean, respectively. Both strains are Gram-stain-negative, rod-shaped, and non-motile, and grow at 10-40 °C, pH 5.0-10.0, in the presence of 1.0-15.0% (w/v) NaCl. Their 16S rRNA gene sequences showed 99.9% similarity. Phylogenetic analysis based on the 16S rRNA gene sequences indicated that both strains belong to the genus Alcanivorax, and share 92.9-98.1% sequence similarity with all valid type strains of this genus, with the highest similarity being to type strain Alcanivorax venustensis DSM 13974T (98.0-98.1%). Digital DNA-DNA hybridization (dDDH) and average nucleotide identity values between strains ST75FaO-1T and 521-1 were 75.7% and 97.1%, respectively, while the corresponding values with A. venustensis DSM 13974T were only 25.4-25.6% and 82.4-82.7%, respectively. The two strains contained similar major cellular fatty acids including C160, C181 ω7c/ω6c, C190 cyclo ω8c, C161 ω7c/ω6c, C120 3-OH, and C120. The genomic G + C content of strains ST75FaO-1T and 521-1 were 66.3% and 66.1%, respectively. Phosphatidylglycerol, phosphatidylethanolamine, two unidentified phospholipids, and one unidentified polar lipid were present in both strains. On the basis of phenotypic and genotypic characteristics, the two strains represent a novel species within the genus Alcanivorax, for which the name Alcanivorax profundimaris sp. nov. is proposed. The type strain is ST75FaO-1T (= **** 1A17714T = KCTC 82142T).Exposure to the industrial solvent trichloroethylene (TCE) has been associated with adverse pregnancy outcomes in humans and decreased fetal weight in rats. TCE kidney toxicity can occur through formation of reactive metabolites via its glutathione (GSH) conjugation metabolic pathway, largely unstudied in the context of pregnancy. To investigate the contribution of the GSH conjugation pathway and oxidative stress to TCE toxicity during pregnancy, we exposed rats orally to 480 mg TCE/kg/day from gestational day (GD) 6 to GD 16 with and without N-acetyl-L-cysteine (NAC) at 200 mg/kg/day or aminooxyacetic acid (AOAA) at 20 mg/kg/day as pre/co-treatments from GD 5-16. NAC is a reactive oxygen species scavenger that modifies the GSH conjugation pathway, and AOAA is an inhibitor of cysteine conjugate β-lyase (CCBL) in the GSH conjugation pathway. TCE decreased fetal weight, and this was prevented by AOAA but not NAC pre/co-treatment to TCE. Although AOAA inhibited CCBL activity in maternal kidney, it did not inhibit CCBL activity in maternal liver and placenta, suggesting that AOAA prevention of TCE-induced decreased fetal weight was due to CCBL activity inhibition in the kidneys but not liver or placenta.
CAO/R. Besides, this research provide some experimental foundation for search and determination of potential therapeutic targets of MCAO/R.The synthesis of purine conjugates with natural amino acids is one of the promising directions in search for novel therapeutic agents, including antimycobacterial agents. The purpose of this study was to synthesize N-(purin-6-yl)dipeptides containing the terminal fragment of (S)-glutamic acid. To obtain the target compounds, two synthetic routes were tested. The first of them is based on coupling of N-(purin-6-yl)-(S)-amino acids to dimethyl (S)-glutamate in the presence of carbodiimide coupling agent followed by the removal of ester groups. However, it turned out that this coupling process was accompanied by racemization of the chiral center of N-(purin-6-yl)-α-amino acids and in all cases led to mixtures of (S,S)- and (R,S)-diastereomers (64). Individual (S,S)-diastereomers were obtained using an alternative approach based on the nucleophilic substitution of chlorine in 6-chloropurine or 2-amino-6-chloropurine with corresponding dipeptides as nucleophiles. The enantiomeric purity of the target compounds was confirmed by chiral HPLC. To test the assumption that racemization of the chiral center of N-(purin-6-yl)-α-amino acids occurs with the participation of nitrogen atoms of the imidazole ring via the stage of formation of a chirally labile intermediate, we obtained such structural analogs of N-(purin-6-yl)-(S)-alanine as N-(9-benzylpurin-6-yl)-(S)-alanine and N-(7-deazapurin-6-yl)-(S)-alanine. It was found that coupling of these compounds to dimethyl (S)-glutamate was also accompanied by racemization. This indicates that the imidazole fragment does not play a crucial role in this process. When testing the antimycobacterial activity of some of the obtained compounds, conjugates with moderate activity against the laboratory Mycobacterium tuberculosis H37Rv strain (MIC 3.1-6.25 μg/mL) were identified.Streptococcus pneumoniae (S. pneumoniae) is the main conditional pathogen of acute respiratory infection in infants, children, and older adults worldwide. https://www.selleckchem.com/products/ly2880070.html It was great significant to identify the epidemic characteristics of serotypes and antibiotic susceptibility for the prevention and treatment of S. pneumoniae diseases. This research assessed the serotype distribution and the minimum inhibitory concentrations (MICs) of S. pneumoniae isolated from pediatric patients to provide information on the epidemiology and antibiotic resistance of S. pneumoniae in Kunming, China. A total of 140 S. pneumoniae isolates were collected from pediatric patients at Kunming Children's Hospital from January 2016 to October 2017. Serotype identification was done by Quellung reaction and multiplex polymerase chain reaction. MICs were determined by E-test. 140 isolates distributed in 13 types of serotypes. The top-three prevalent serotypes were 19F, 19A, and 6B. The immunization coverage rate of 13-valent pneumococcal conjugate vaccine (PCV) was relatively higher and should be introduced into the vaccination program in the region. MIC50 of penicillin, ceftriaxone, and levofloxacin was 1 μg/mL. MIC50 for meropenem and vancomycin was 0.38 μg/mL. MIC90 of penicillin, ceftriaxone, and levofloxacin was 1.5 μg/mL and that of meropenem and vancomycin was 0.5 μg/mL. The MIC90 of erythromycin was > 256 μg/mL. In summary, S. pneumoniae had low resistance rates to penicillin, ceftriaxone, levofloxacin, vancomycin, and meropenem, and these antibiotics could be the first-line agents for children with pneumococcal infections in Kunming.Two novel Alcanivorax-related strains, designated ST75FaO-1T and 521-1, were isolated from the seawater of the South China Sea and the deep-sea sediment of the West Pacific Ocean, respectively. Both strains are Gram-stain-negative, rod-shaped, and non-motile, and grow at 10-40 °C, pH 5.0-10.0, in the presence of 1.0-15.0% (w/v) NaCl. Their 16S rRNA gene sequences showed 99.9% similarity. Phylogenetic analysis based on the 16S rRNA gene sequences indicated that both strains belong to the genus Alcanivorax, and share 92.9-98.1% sequence similarity with all valid type strains of this genus, with the highest similarity being to type strain Alcanivorax venustensis DSM 13974T (98.0-98.1%). Digital DNA-DNA hybridization (dDDH) and average nucleotide identity values between strains ST75FaO-1T and 521-1 were 75.7% and 97.1%, respectively, while the corresponding values with A. venustensis DSM 13974T were only 25.4-25.6% and 82.4-82.7%, respectively. The two strains contained similar major cellular fatty acids including C160, C181 ω7c/ω6c, C190 cyclo ω8c, C161 ω7c/ω6c, C120 3-OH, and C120. The genomic G + C content of strains ST75FaO-1T and 521-1 were 66.3% and 66.1%, respectively. Phosphatidylglycerol, phosphatidylethanolamine, two unidentified phospholipids, and one unidentified polar lipid were present in both strains. On the basis of phenotypic and genotypic characteristics, the two strains represent a novel species within the genus Alcanivorax, for which the name Alcanivorax profundimaris sp. nov. is proposed. The type strain is ST75FaO-1T (= MCCC 1A17714T = KCTC 82142T).Exposure to the industrial solvent trichloroethylene (TCE) has been associated with adverse pregnancy outcomes in humans and decreased fetal weight in rats. TCE kidney toxicity can occur through formation of reactive metabolites via its glutathione (GSH) conjugation metabolic pathway, largely unstudied in the context of pregnancy. To investigate the contribution of the GSH conjugation pathway and oxidative stress to TCE toxicity during pregnancy, we exposed rats orally to 480 mg TCE/kg/day from gestational day (GD) 6 to GD 16 with and without N-acetyl-L-cysteine (NAC) at 200 mg/kg/day or aminooxyacetic acid (AOAA) at 20 mg/kg/day as pre/co-treatments from GD 5-16. NAC is a reactive oxygen species scavenger that modifies the GSH conjugation pathway, and AOAA is an inhibitor of cysteine conjugate β-lyase (CCBL) in the GSH conjugation pathway. TCE decreased fetal weight, and this was prevented by AOAA but not NAC pre/co-treatment to TCE. Although AOAA inhibited CCBL activity in maternal kidney, it did not inhibit CCBL activity in maternal liver and placenta, suggesting that AOAA prevention of TCE-induced decreased fetal weight was due to CCBL activity inhibition in the kidneys but not liver or placenta.
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