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21.
Inflammatory bowel disease (IBD), as a chronic and recurrent inflammatory disorder, is caused by a dysregulated and aberrant immune response to exposed environmental factors in genetically susceptible individuals. Despite huge efforts in determining the molecular pathogenesis of IBD, an increasing worldwide incidence of IBD has been reported. MicroRNAs (miRNAs) are a set of noncoding RNA molecules that are about 22 nucleotides long, and these molecules are involved in the regulation of the gene expression. By clarifying the important role of miRNAs in a number of diseases, their role was also considered in IBD; numerous studies have been performed on this topic. In this review, we attempt to summarize a number of studies and discuss some of the recent developments in the roles of miRNAs in the pathophysiology, diagnosis, and treatment of IBD.  相似文献   
22.
Saccharomyces cerevisiae NAD(H)‐dependent 2,3‐butanediol dehydrogenase (Bdh1), a medium chain dehydrogenase/reductase is the main enzyme catalyzing the reduction of acetoin to 2,3‐butanediol. In this work we focused on altering the coenzyme specificity of Bdh1 from NAD(H) to NADP(H). Based on homology studies and the crystal structure of the NADP(H)‐dependent yeast alcohol dehydrogenase Adh6, three adjacent residues (Glu221, Ile222, and Ala223) were predicted to be involved in the coenzyme specificity of Bdh1 and were altered by site‐directed mutagenesis. Coenzyme reversal of Bdh1 was obtained with double Glu221Ser/Ile222Arg and triple Glu221Ser/Ile222Arg/Ala223Ser mutants. The performance of the triple mutant for NADPH was close to that of native Bdh1 for NADH. The three engineered mutants were able to restore the growth of a phosphoglucose isomerase deficient strain (pgi), which cannot grow on glucose unless an alternative NADPH oxidizing system is provided, thus demonstrating their in vivo functionality. These mutants are interesting tools to reduce the excess of acetoin produced by engineered brewing or wine yeasts overproducing glycerol. In addition, they represent promising tools for the manipulation of the NADP(H) metabolism and for the development of a powerful catalyst in biotransformations requiring NADPH regeneration. Biotechnol. Bioeng. 2009; 104: 381–389 © 2009 Wiley Periodicals, Inc.  相似文献   
23.
Molecular Biology Reports - Adipose tissue (AT) is a passive reservoir for energy storage and an active endocrine organ responsible for synthesizing bioactive molecules called...  相似文献   
24.
In this work, the synthesis, characterization, and biological activities of a new series of 1,3,4-thiadiazole derivatives were investigated. The structures of final compounds were identified using 1H-NMR, 13C-NMR, elemental analysis, and HRMS. All the new synthesized compounds were then screened for their antimicrobial activity against four types of pathogenic bacteria and one fungal strain, by application of the MIC assays, using Ampicilin, Gentamycin, Vancomycin, and Fluconazole as standards. Among the compounds, the MIC values of 4 and 8 μg/mL of the compounds 3f and 3g , respectively, are remarkable and indicate that these compounds are good candidates for antifungal activity. The docking experiments were used to identify the binding forms of produced ligands with sterol 14-demethylase to acquire insight into relevant proteins. The MD performed about 100 ns simulations to validate selected compounds’ theoretical studies. Finally, using density functional theory (DFT) to predict reactivity, the chemical characteristics and quantum factors of synthesized compounds were computed. These results were then correlated with the experimental data. Furthermore, computational estimation was performed to predict the ADME properties of the most active compound 3f .  相似文献   
25.
Resistance to antimicrobial agents is a concern that exists globally and has a considerable impact on human and animal health, so that the discovery of new antibacterial compounds has become increasingly more important in combating infectious disease. In this paper, imidazo[4,5-a]quinindolines are introduced as new antibacterial agents against Gram-positive and Gram-negative bacteria. These pentacyclic compounds are synthesized by the reaction of N-alkyl-5-nitrobenzimidazoles with 2-(1-alkyl-1H-3-indolyl)acetonitrile under basic conditions in excellent yields. The structures of newly synthesized compounds were characterized by IR, 1H NMR, 13C NMR, and mass spectral data. The antibacterial activities of the synthesized compounds were screened against standard strains of two Gram-positive and two Gram-negative bacteria using the broth microdilution method. Most of the compounds studied showed promising activities against both types of bacteria.  相似文献   
26.
Leishmaniasis is a worldwide disease that leads to high mortality and morbidity in human populations. Today, leishmaniasis is managed via drug therapy. The drugs that are already in clinical use are limited to a number of toxic chemical compounds and their parasite drug resistance is increasing. It is therefore essential, in order to circumvent the current difficulties, to design a new anti-leishmanial drug treatment strategy. Besides producing new, active anti-leishmanial entities, another promising strategy could be developing novel delivery systems and formulations of the existing pharmaceutical ingredients to improve drug efficacy. In the present study, paromomycin sulfate (PM), as one of the promising anti-leishmanial drugs, was formulated in solid lipid nanoparticles (SLN), and its in vitro efficacy was investigated against different strains of Leishmania using a MTT test, Parasite-Rescue-Transformation-Assay, SYTO Green staining, and fluorescent microscope imaging. The results show that PM-loaded SLN is significantly more effective than PM in inhibiting parasite propagation (P?<?0.05) and that cytotoxicity of PM-SLN formulations is size dependent. According to our results, delivery of the drugs to the macrophages via nanoparticle utilization seems to be an accessible and practical approach.  相似文献   
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28.
This study aims at determining the association between markers of hepatic injury and serum, urinary, and intra-erythrocyte magnesium concentrations and dietary magnesium intake in obese children and adolescents. In a case–control study, 42 obese children and adolescents (8–18 years) and 42 sex- and puberty-matched controls were studied. Serum, urinary, and intra-erythrocyte magnesium levels, indices of insulin sensitivity, and liver enzymes were measured. Dietary magnesium intake was assessed using a food frequency questionnaire. Obese children and adolescents exhibited insulin resistance as determined by a higher fasting insulin and the HOMA-IR (p < 0.001) and lower QUICKI indices (p = 0.001); in addition these subjects had significantly higher intra-erythrocyte magnesium (IEM) concentrations, than non-obese ones (3.99 ± 1.05 vs. 3.35 ± 1.26 mg/dL of packed cell; p = 0.015). Among liver enzymes, only gamma-glutamyl transferase (GGT) was significantly higher in obese than in non-obese subjects (22.7 ± 9.4 vs. 17.1 ± 7.9 U/l; p = 0.002). A positive association was found between GGT and IEM in both groups; however in multivariate analysis, in obese subjects, only GGT (p = 0.026) and, in non-obese subjects, only age (p = 0.006) remained as significant predictors of IEM. In conclusion, increased IEM concentration was seen in insulin-resistant obese children and adolescents; furthermore, serum GGT was associated with IEM, independently of body mass index and HOMA-IR.  相似文献   
29.
Biological Trace Element Research - The prevalence of hypertension (HTN) is increasing globally. It has been shown that there is an association between micronutrient deficiency and HTN. In the...  相似文献   
30.
Albumin is a multifunctional non-glycosylated, negatively charged plasma protein, with extraordinary ligand-binding and transport properties, antioxidant functions, and enzymatic activities. Physiologically, albumin transports free fatty acids in plasma and contributes in maintaining colloid osmotic pressure. Recent progresses in using albumin as a versatile protein carrier for drug targeting and for improving the pharmacokinetic profile of peptide or protein-based drugs, increased the attempts for improving albumin stability. Studying the thermal stability of camel albumin may provide us not only new clues for designing recombinant albumins, but also molecular insights on camel physiology. This study aims to determine the thermal stability of camel albumin. Fatted camel serum albumin (FCSA) was purified from blood via combination of Cohn’s method and anion-exchange chromatography. Activated charcoal treatment was used to obtain defatted camel serum albumin (CSA). Fluorescence spectroscopy and differential scanning calorimetry (DSC) were used to study thermal denaturation of this protein. The set of fluorescence spectra were deconvoluted using the convex constraint analysis method (CCA). The results from deconvolution of fluorescence spectroscopy and DSC showed three and two components for CSA and FCSA, respectively. The bimodal DSC transition can be attributed to a crevice between domains I and II and formation of two independent thermodynamic domains. The crevice formation can be prevented by fatty acid binding between domains I and II. The calculated values of ?H v/?H cal, approximately 0.4 for CSA and near 1 for FCSA, confirmed the presence of at least one intermediate in thermal unfolding of CSA and the absence of the intermediate for FCSA. The obtained midpoint transition temperature (T m) of FCSA was about 20 °C higher than that of CSA. Such enormous stabilizing effect may be attributed to the fact that fatty acid serves as glue which preserves different domains beside each other and prevents formation of the mentioned intermediate.  相似文献   
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