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31.
Combinations of five diluents (0.1% peptone, 40 and 50% glucose, and 18 and 26% glycerol) and three enumeration media (tryptone glucose yeast extract, dichloran 18% glycerol and malt extract yeast extract 50% glucose (MY50G) agars) were evaluated for recovering a xerotolerant yeast, Zygosaccharomyces rouxii , from foods with intermediate water activity ( a w ). Combinations of 40% ( a w , 0.936) or 50% ( a w 0.898) glucose diluent and MY50G agar ( a w 0.890) were superior in recovering highest populations. The type of solute in the diluent, as well as a reduced a w , influences efficiency of recovering viable cells. 相似文献
32.
Recent evidences show that osthole possesses anti-inflammatory properties and protective effects following shock-like states, but the mechanism of these effects remains unknown. The p38 mitogen-activated protein kinase (p38 MAPK) pathway exerts anti-inflammatory effects in injury. The aim of this study was to investigate whether p38 MAPK plays any role in the osthole-mediated attenuation of hepatic injury after trauma-hemorrhage. Male Sprague-Dawley rats underwent trauma-hemorrhage (mean blood pressure maintained at approximately 35–40 mmHg for 90 minutes), followed by fluid resuscitation. During resuscitation, a single dose of osthole (3 mg/kg, intravenously) with and without a p38 MAPK inhibitor SB-203580 (2 mg/kg, intravenously), SB-203580 or vehicle was administered. Plasma alanine aminotransferase (ALT) with aspartate aminotransferase (AST) concentrations and various hepatic parameters were measured (n = 8 rats/group) at 24 hours after resuscitation. The results showed that trauma-hemorrhage increased hepatic myeloperoxidase activity, intercellular adhesion molecule-1 and interleukin-6 levels, and plasma ALT and AST concentrations. These parameters were significantly improved in the osthole-treated rats subjected to trauma-hemorrhage. Osthole treatment also increased hepatic phospho-p38 MAPK expression compared with vehicle-treated trauma-hemorrhaged rats. Co-administration of SB-203580 with osthole abolished the osthole-induced beneficial effects on the above parameters and hepatic injury. These results suggest that the protective effect of osthole administration on alleviation of hepatic injury after trauma-hemorrhage, which is, at least in part, through p38 MAPK-dependent pathway. 相似文献
33.
Eun-Young Won Mi-Kyung Yoon Sang-Woo Kim Youngae Jung Hyun-Whee Bae Daeyoup Lee Sung Goo Park Chul-Ho Lee Geum-Sook Hwang Seung-Wook Chi 《PloS one》2013,8(10)
Despite the numerous metabolic studies on obesity, gender bias in obesity has rarely been investigated. Here, we report the metabolomic analysis of obesity by using leptin-deficient ob/ob mice based on the gender. Metabolomic analyses of urine and serum from ob/ob mice compared with those from C57BL/6J lean mice, based on the 1H NMR spectroscopy in combination with multivariate statistical analysis, revealed clear metabolic differences between obese and lean mice. We also identified 48 urine and 22 serum metabolites that were statistically significantly altered in obese mice compared to lean controls. These metabolites are involved in amino acid metabolism (leucine, alanine, ariginine, lysine, and methionine), tricarbocylic acid cycle and glucose metabolism (pyruvate, citrate, glycolate, acetoacetate, and acetone), lipid metabolism (cholesterol and carnitine), creatine metabolism (creatine and creatinine), and gut-microbiome-derived metabolism (choline, TMAO, hippurate, p-cresol, isobutyrate, 2-hydroxyisobutyrate, methylamine, and trigonelline). Notably, our metabolomic studies showed distinct gender variations. The obese male mice metabolism was specifically associated with insulin signaling, whereas the obese female mice metabolism was associated with lipid metabolism. Taken together, our study identifies the biomarker signature for obesity in ob/ob mice and provides biochemical insights into the metabolic alteration in obesity based on gender. 相似文献
34.
Two distinct forms of β-glucosidase, A and B, were found to occur in the cells of Pseudomonas fluorescens var. cellulosa : A was membrane-bound, while B cytosolic. They differed also from each other in some properties, such as molecular size, kinetic parameters, and susceptibility to various compounds. β-Glucosidase B was partially purified and studied especially of its substrate specificity. The results indicated that it may be an atypical β-glucosidase which possesses a certain character of exo-cellulase. 相似文献
35.
Hahn Kyu Ri Kim Woosuk Jung Hyo Young Kwon Hyun Jung Kim Dae Won Hwang In Koo Yoon Yeo Sung 《Neurochemical research》2022,47(4):1073-1082
Neurochemical Research - Cuprizone is commonly used to induce neuronal demyelination in mice. In the present study, we compared the cuprizone-induced demyelination in the corpus callosum and... 相似文献
36.
This article describes DP-Bind, a web server for predicting DNA-binding sites in a DNA-binding protein from its amino acid sequence. The web server implements three machine learning methods: support vector machine, kernel logistic regression and penalized logistic regression. Prediction can be performed using either the input sequence alone or an automatically generated profile of evolutionary conservation of the input sequence in the form of PSI-BLAST position-specific scoring matrix (PSSM). PSSM-based kernel logistic regression achieves the accuracy of 77.2%, sensitivity of 76.4% and specificity of 76.6%. The outputs of all three individual methods are combined into a consensus prediction to help identify positions predicted with high level of confidence. AVAILABILITY: Freely available at http://lcg.rit.albany.edu/dp-bind. SUPPLEMENTARY INFORMATION: http://lcg.rit.albany.edu/dp-bind/dpbind_supplement.html. 相似文献
37.
Choi H Jin JY Choi S Hwang JU Kim YY Suh MC Lee Y 《The Plant journal : for cell and molecular biology》2011,65(2):181-193
The exine of the pollen wall shows an intricate pattern, primarily comprising sporopollenin, a polymer of fatty acids and phenolic compounds. A series of enzymes synthesize sporopollenin precursors in tapetal cells, and the precursors are transported from the tapetum to the pollen surface. However, the mechanisms underlying the transport of sporopollenin precursors remain elusive. Here, we provide evidence that strongly suggests that the Arabidopsis ABC transporter ABCG26/WBC27 is involved in the transport of sporopollenin precursors. Two independent mutations at ABCG26 coding region caused drastic decrease in seed production. This defect was complemented by expression of ABCG26 driven by its native promoter. The severely reduced fertility of the abcg26 mutants was caused by a failure to produce mature pollen, observed initially as a defect in pollen-wall development. The reticulate pattern of the exine of wild-type microspores was absent in abcg26 microspores at the vacuolate stage, and the vast majority of the mutant pollen degenerated thereafter. ABCG26 was expressed specifically in tapetal cells at the early vacuolate stage of pollen development. It showed high co-expression with genes encoding enzymes required for sporopollenin precursor synthesis, i.e. CYP704B1, ACOS5, MS2 and CYP703A2. Similar to two other mutants with defects in pollen-wall deposition, abcg26 tapetal cells accumulated numerous vesicles and granules. Taken together, these results suggest that ABCG26 plays a crucial role in the transfer of sporopollenin lipid precursors from tapetal cells to anther locules, facilitating exine formation on the pollen surface. 相似文献
38.
S. O. Hwang G. H. Gil Y. J. Cho K. R. Kang J. H. Lee J. C. Bae 《Applied microbiology and biotechnology》1985,22(2):108-113
Summary A process for l-phenylalanine production was studied using a tyrosine auxotrophic regulatory mutant of Escherichia coli, resistant to both -2-thienyl-dl-alanine and p-fluoro-dl-phenylalanine. Fermentations were carried out in a 30-1 fermentor with intermittent feeding of glucose plus phosphate. The mutant accumulated l-phenylalanine in the fermentation broth up to 15 g/l at pH 7.0 and 33°C. Column chromatography on a strong cation exchanger was employed as the most effective step in the purification of l-phenyl-alanine from the broth. This step brought about 4-fold concentration of the product with 96% recovery. 相似文献
39.
Ahmed H.E. Hassan Min Chang Cho Hye In Kim Ji Seul Yang Kyung Tae Park Ji Young Hwang Choon-Gon Jang Ki Duk Park Yong Sup Lee 《Bioorganic & medicinal chemistry》2018,26(18):5069-5078
CRA13; a peripheral dual CB1R/CB2R agonist with clinically proven analgesic properties, infiltrates into CNS producing adverse effects due to central CB1R agonism. Such adverse effects might be circumvented by less lipophilic compounds with attenuated CB1R affinity. Metabolism produces less lipophilic metabolites that might be active metabolites. Some CRA13 oxidative metabolites and their analogues were synthesized as less lipophilic CRA13 analogues. Probing their CB1R and CB2R activity revealed the alcohol metabolite 8c as a more potent and more effective CB2R ligand with attenuated CB1R affinity relative to CRA13. Also, the alcohol analogue 8b and methyl ester 12a possessed enhanced CB2R affinity and reduced CB1R affinity. The CB2R binding affinity of alcohol analogue 8b was similar to CRA13 while that of methyl ester 12a was more potent. In silico study provided insights into the possible molecular interactions that might explain the difference in the elicited biological activity of these compounds. 相似文献
40.