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21.

Background

Role of multidrug resistance-1 (MDR-1) gene polymorphisms has not been clarified in nephrotic syndrome (NS). Additionally, researchers studied several genetic polymorphisms to explain their influence on different patients' responses to steroid; however the data were inconsistent. Therefore, we aimed to investigate the association of MDR-1 gene polymorphisms [C1236T, G2677T/A, C3435T] and haplotypes with susceptibility to childhood nephrotic syndrome, and whether they influence steroid response.

Methods

We detected MDR-1 gene polymorphisms using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) in 138 NS patients and 140 age and sex matched healthy children.

Results

The frequencies of MDR1 G2677T/A GT, GA, TT + AA genotypes or T allele, MDR1 C3435T TT genotype, and T allele genotype frequencies were significantly increased in NS group. While no significant differences were observed in distributions of C1236T genotypes or allele between NS patients and healthy children. Moreover, steroid non-responder NS patients had significantly higher frequencies of MDR1 G2677T/A GT, GA, and TT + AA genotypes than steroid responsive NS patients. We observed also that NS patients with age less than 6 years old had increased frequencies of MDR1 G2677T/A GT, GA, TT + AA genotypes or T allele MDR1 C3435T CT, TT genotypes and T allele. Interestingly the frequency of the TGC haplotype of MDR1 was lower in the initial steroid responders than in non-responders NS patients. On the contrary, there were no any association between the MDR1 haplotypes with NS susceptibility and they did not influence renal pathological findings.

Conclusion

Our data suggested that MDR1 C3435T or G2677T/A gene polymorphisms are risk factors of increased susceptibility, earlier onset of NS, and steroid resistance.  相似文献   
22.
Using the monomolecular film technique, we studied interfacial properties of Fusarium solani lipase (FSL). This lipolytic enzyme was found to be unique among the fungal lipases possessing not only a lipase activity but also a high phospholipase one.The FSL was able to hydrolyze dicaprin films at various surface pressures. The surface pressure dependency, the stereospecificity, and the regioselectivity of FSL were performed using optically pure stereoisomers of diglyceride (1,2‐sn‐ dicaprin and 2,3‐sn‐dicaprin) and a prochiral isomer (1,3‐sn‐dicaprin) spread as monomolecular films at the air–water interface. The FSL prefers adjacent ester groups of the diglyceride isomers (1,2‐sn‐dicaprin and 2,3‐sn‐dicaprin) at low and high surface pressures. Furthermore, FSL was found to be markedly stereospecific for the sn‐1 position of the 1,2‐sn‐enantiomer of dicaprin at both low and high surface pressures.Moreover, FSL shows high activities on phospholipids monolayers. However, this enzyme displays high preference to zwitterionic phospholipids compared to the negatively charged ones. Chirality, 25:35‐38, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
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Intrauterine growth restriction (IUGR) is an obstetric complication characterised by placental insufficiency and secondary cardiovascular remodelling that can lead to cardiomyopathy in adulthood. Despite its aetiology and potential therapeutics are poorly understood, bioenergetic deficits have been demonstrated in adverse foetal and cardiac development. We aimed to evaluate the role of mitochondria in human pregnancies with IUGR. In a single‐site, cross‐sectional and observational study, we included placenta and maternal peripheral and neonatal cord blood mononuclear cells (PBMC and CBMC) from 14 IUGR and 22 control pregnancies. The following mitochondrial measurements were assessed: enzymatic activities of mitochondrial respiratory chain (MRC) complexes I, II, IV, I + III and II + III, oxygen consumption (cell and complex I‐stimulated respiration), mitochondrial content (citrate synthase [CS] activity and mitochondrial DNA copy number), total ATP levels and lipid peroxidation. Sirtuin3 expression was evaluated as a potential regulator of bioenergetic imbalance. Intrauterine growth restriction placental tissue showed a significant decrease of MRC CI enzymatic activity (P < 0.05) and CI‐stimulated oxygen consumption (P < 0.05) accompanied by a significant increase of Sirtuin3/β‐actin protein levels (P < 0.05). Maternal PBMC and neonatal CBMC from IUGR patients presented a not significant decrease in oxygen consumption (cell and CI‐stimulated respiration) and MRC enzymatic activities (CII and CIV). Moreover, CS activity was significantly reduced in IUGR new‐borns (P < 0.05). Total ATP levels and lipid peroxidation were preserved in all the studied tissues. Altered mitochondrial function of IUGR is especially present at placental and neonatal level, conveying potential targets to modulate obstetric outcome through dietary interventions aimed to regulate Sirtuin3 function.  相似文献   
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International Journal of Peptide Research and Therapeutics - The success of endodontic treatments depends on the elimination of intracanal pathogens. Since irrigation and instrumentation can only...  相似文献   
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Extremophiles - The prokaryotic communities of water bodies contaminated by acid mine drainage from the São Domingos mining area in southern Portugal were analyzed using a meta-taxonomics...  相似文献   
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