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Twenty three fused carbazole–imidazoles 6a–w were designed, synthesized, and screened as new α-glucosidase inhibitors. All the synthesized fused carbazole-imidazoles 6a-w were found to be more active than acarbose (IC50?=?750.0?±?1.5?µM) against yeast α-glucosidase with IC50 values in the range of 74.0?±?0.7–298.3?±?0.9?µM. Kinetic study of the most potent compound 6v demonstrated that this compound is a competitive inhibitor for α-glucosidase (Ki value?=?75?µM). Furthermore, the in silico studies of the most potent compounds 6v and 6o confirmed that these compounds interacted with the key residues in the active site of α-glucosidase.  相似文献   
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The characterization of nematode-effective strains and cry genes in the Iranian Bacillus thuringiensis (Bt) collection (70 isolates) is presented. Characterization was based on PCR analysis using 12 specific primers for cry5, cry6, cry12, cry13, cry14, and cry21 genes encoding proteins active against nematodes, crystal morphology, and protein band patterns as well as their nematicidal activity on root-knot nematode (Meloidogyne incognita) and two free-living nematodes (Chiloplacus tenuis and Acrobeloides enoplus). PCR results with primers for these genes showed that 22 isolates (31.5%) contain a minimum of one nematode-active cry gene. Strains containing the cry6 gene were the most abundant and represent 22.8% of the isolates. Bt strains harboring cry14 genes were also abundant (14.2%). cry21 and cry5 genes were less abundant, found in 4.2% and 2.8% of the strains, respectively. In total, six different nematode-active cry gene profiles were detected in this collection. Four isolates did not show the expected PCR product size for cry5, cry6, and cry21 genes; they might contain potentially novel insecticidal crystal protein genes. Twenty-two Bt isolates containing nematode-active cry genes were selected for preliminary bioassays on M. incognita. Based on these bioassays, four isolates were selected for detailed bioassays. Isolates YD5 and KON4 at 2 x 10(8) CFU/mL concentrations showed 77% and 81% toxicity on M. incognita, respectively. The free-living nematodes C. tenuis and A. enoplus were more susceptible and the highest mortality was observed within 48 h of incubation at all of the concentrations tested. Maximum mortality was recorded for isolates SN1 and KON4 at 2 x 10(8) CFU/mL concentrations and resulted in 68% and 77% adults deaths of C. tenuis and 68% and 72% for A. enoplus, respectively. Our results showed that PCR is a useful technique for toxicity prediction of nematicidal Bt isolates.  相似文献   
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Lipase maturation factor 1 (LMF1) is predicted to be a polytopic protein localized to the endoplasmic reticulum (ER) membrane. It functions in the post-translational attainment of enzyme activity for both lipoprotein lipase and hepatic lipase. By using transmembrane prediction methods in mouse and human orthologs, models of LMF1 topology were constructed and tested experimentally. Employing a tagging strategy that used insertion of ectopic glycan attachment sites and terminal fusions of green fluorescent protein, we established a five-transmembrane model, thus dividing LMF1 into six domains. Three domains were found to face the cytoplasm (the amino-terminal domain and loops B and D), and the other half was oriented to the ER lumen (loops A and C and the carboxyl-terminal domain). This representative model shows the arrangement of an evolutionarily conserved domain within LMF1 (DUF1222) that is essential to lipase maturation. DUF1222 comprises four of the six domains, with the two largest ones facing the ER lumen. We showed for the first time, using several naturally occurring variants featuring DUF1222 truncations, that Lmf1 interacts physically with lipoprotein lipase and hepatic lipase and localizes the lipase interaction site to loop C within DUF1222. We discuss the implication of our results with regard to lipase maturation and DUF1222 domain structure.  相似文献   
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The mycotoxin, cyclopiazonic acid (CPA), was detected at concentrations as high as 9 ppm in 21 of 26 corn samples from a Bogor poultry feedmill. This is the first demonstration of the natural occurrence of CPA in Indonesia. CPA was always accompanied by other mycotoxins, especially aflatoxins, suggesting that the interactive toxicity of these mycotoxins to poultry should be investigated.  相似文献   
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Gastric cancer is the second cause of cancer-related mortality and the fourth most common cancers worldwide. Owing to the immune modulatory effect of vitamin D in the body, the role of vitamin D receptor gene in vitamin D regulation receives a great deal of research interest. The aim of the current study was to highlight the association between two variants of TaqI and FokI in the vitamin D receptor gene and gastric cancer predisposition in a sample of South Khorasan population. The present investigation consisted of 69 patients affected with gastric cancer and 100 healthy individuals. The genomic DNA was extracted by salting out the protocol from peripheral venous blood. Genotyping of TaqI and FokI variants were performed by PCR-RFLP method. Our findings manifested that TC genotype of TaqI polymorphism was statistically significant between the case and the control groups (p = 0.002). Moreover, the frequency of TC + CC genotypes was statistically significant between the two groups (p = 0.009). Furthermore, we could not find any meaningful association between FokI variant and the participant groups. The present results declared that, in our population, TC genotype of TaqI polymorphism has an association with gastric cancer susceptibility. In addition, more investigation with greater sample sizes is needed to confirm our results.  相似文献   
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