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31.
Reoccurrence of infectious diseases and ability of pathogens to resist antibacterial action has raised enormous challenges which may possibly be confronted by nanotechnology routes. In the present study, uniformly embedded silver nanoparticles in orthorhombic nanotubes of lithium vanadium oxide (LiV2O5/Ag) were explored as an impeder of bacterial growth and biofilm. The LiV2O5/Ag nanocomposites have impeded growth of Gram-positive Bacillus subtilis NCIM 2063 and Gram-negative Escherichia coli NCIM 2931 at 60 to 120 μg/mL. It also impeded the biofilm in Pseudomonas aeruginosa NCIM 2948 at 12.5 to 25 μg/mL. Impedance in the growth and biofilm occurs primarily by direct action of the nanocomposites on the cell surfaces of test organisms as revealed by surface perturbation in scanning electron microscopy. As the metabolic growth and biofilm formation phenomena of pathogens play a central role in progression of pathogenesis, LiV2O5/Ag nanocomposite-based approach is likely to curb the menace of reoccurrence of infectious diseases. Thus, LiV2O5/Ag nanocomposites can be viewed as a promising candidate in biofabrication of biomedical materials.  相似文献   
32.

INTRODUCTION:

Non-syndromic tooth agenesis is a congenital anomaly with significant medical, psychological, and social ramifications. There is sufficient evidence to hypothesize that locus for this condition can be identified by candidate genes.

AIM OF THE STUDY:

The aim of this study was to test whether MSX1 671 T > C gene variant was involved in etiology of non-syndromic tooth agenesis in Raichur patients.

MATERIALS AND METHODS:

Blood samples were collected with informed consent from 50 subjects having non-syndromic tooth agenesis and 50 controls. Genomic deoxyribonucleic acid (DNA) was extracted from the blood samples, polymerase chain reaction (PCR) was performed, and restriction fragment length polymorphism (RFLP) was performed for digestion products that were evaluated.

RESULTS:

The results showed positive correlation between MSX1671 T > C gene variant and non-syndromic tooth agenesis in Raichur patients.

CONCLUSION:

MSX1 671 T > C gene variant may be a good screening marker for non-syndromic tooth agenesis in Raichur patients.  相似文献   
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Mitochondrial DNA (mtDNA) copy number in peripheral blood is associated with increased risk of several cancers. However, data from prospective studies on mtDNA copy number and breast cancer risk are lacking. We evaluated the association between mtDNA copy number in peripheral blood and breast cancer risk in a nested case-control study of 183 breast cancer cases with pre-diagnostic blood samples and 529 individually matched controls among participants of the Singapore Chinese Health Study. The mtDNA copy number was measured using real time PCR. Conditional logistic regression analyses showed that there was an overall positive association between mtDNA copy number and breast cancer risk (Ptrend = 0.01). The elevated risk for higher mtDNA copy numbers was primarily seen for women with <3 years between blood draw and cancer diagnosis; ORs (95% CIs) for 2nd, 3rd, 4th, and 5th quintile of mtDNA copy number were 1.52 (0.61, 3.82), 2.52 (1.03, 6.12), 3.12 (1.31, 7.43), and 3.06 (1.25, 7.47), respectively, compared with the 1st quintile (Ptrend = 0.004). There was no association between mtDNA copy number and breast cancer risk among women who donated a blood sample ≥3 years before breast cancer diagnosis (Ptrend = 0.41). This study supports a prospective association between increased mtDNA copy number and breast cancer risk that is dependent on the time interval between blood collection and breast cancer diagnosis. Future studies are warranted to confirm these findings and to elucidate the biological role of mtDNA copy number in breast cancer risk.  相似文献   
35.
Cytochrome P450 3A4 (CYP3A4) is the major drug metabolic enzyme, and is involved in the metabolism of antiretroviral drugs, especially protease inhibitors (PIs). This study was undertaken to examine the effect of methamphetamine on the binding and metabolism of PIs with CYP3A4. We showed that methamphetamine exhibits a type I spectral change upon binding to CYP3A4 with δAmax and KD of 0.016±0.001 and 204±18 μM, respectively. Methamphetamine-CYP3A4 docking showed that methamphetamine binds to the heme of CYP3A4 in two modes, both leading to N-demethylation. We then studied the effect of methamphetamine binding on PIs with CYP3A4. Our results showed that methamphetamine alters spectral binding of nelfinavir but not the other type I PIs (lopinavir, atazanavir, tipranavir). The change in spectral binding for nelfinavir was observed at both δAmax (0.004±0.0003 vs. 0.0068±0.0001) and KD (1.42±0.36 vs.2.93±0.08 μM) levels. We further tested effect of methamphetamine on binding of 2 type II PIs; ritonavir and indinavir. Our results showed that methamphetamine alters the ritonavir binding to CYP3A4 by decreasing both the δAmax (0.0038±0.0003 vs. 0.0055±0.0003) and KD (0.043±0.0001 vs. 0.065±0.001 nM), while indinavir showed only reduced KD in presence of methamphetamine (0.086±0.01 vs. 0.174±0.03 nM). Furthermore, LC-MS/MS studies in high CYP3A4 human liver microsomes showed a decrease in the formation of hydroxy ritonavir in the presence of methamphetamine. Finally, CYP3A4 docking with lopinavir and ritonavir in the absence and presence of methamphetamine showed that methamphetamine alters the docking of ritonavir, which is consistent with the results obtained from spectral binding and metabolism studies. Overall, our results demonstrated differential effects of methamphetamine on the binding and metabolism of PIs with CYP3A4. These findings have clinical implication in terms of drug dose adjustment of antiretroviral medication, especially with ritonavir-boosted antiretroviral therapy, in HIV-1-infected individuals who abuse methamphetamine.  相似文献   
36.
HIV incidence estimates are used to monitor HIV-1 infection in the United States. Use of laboratory biomarkers that distinguish recent from longstanding infection to quantify HIV incidence rely on having accurate knowledge of the average time that individuals spend in a transient state of recent infection between seroconversion and reaching a specified biomarker cutoff value. This paper describes five estimation procedures from two general statistical approaches, a survival time approach and an approach that fits binomial models of the probability of being classified as recently infected, as a function of time since seroconversion. We compare these procedures for estimating the mean duration of recent infection (MDRI) for two biomarkers used by the U.S. National HIV Surveillance System for determination of HIV incidence, the Aware BED EIA HIV-1 incidence test (BED) and the avidity-based, modified Bio-Rad HIV-1/HIV-2 plus O ELISA (BRAI) assay. Collectively, 953 specimens from 220 HIV-1 subtype B seroconverters, taken from 5 cohorts, were tested with a biomarker assay. Estimates of MDRI using the non-parametric survival approach were 198.4 days (SD 13.0) for BED and 239.6 days (SD 13.9) for BRAI using cutoff values of 0.8 normalized optical density and 30%, respectively. The probability of remaining in the recent state as a function of time since seroconversion, based upon this revised statistical approach, can be applied in the calculation of annual incidence in the United States.  相似文献   
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Hypoxic preconditioning (HPC) may protect multiple organs from various injuries. We hypothesized that HPC would reduce lung injury in patients undergoing thoracoscopic lobectomy. In a prospective randomized controlled trial, 70 patients undergoing elective thoracoscopic lobectomy were randomly allocated to the HPC group or the control group. Three cycles of 5-min hypoxia and 3-min ventilation applied to the nondependent lung served as the HPC intervention. The primary outcome was the PaO2/FiO2 ratio. Secondary outcomes included postoperative pulmonary complications, pulmonary function, and duration of hospital stay. HPC significantly increased the PaO2/FiO2 ratio compared with the control at 30 min after one-lung ventilation and 7 days after operation. Compared with the control, it also significantly improved postoperative pulmonary function and markedly reduced the postoperative hospital stay duration. No significant differences between groups were observed in the incidence of pulmonary complications or overall postoperative morbidity. HPC improves postoperative oxygenation, enhances the recovery of pulmonary function, and reduces the duration of hospital stay in patients undergoing thoracoscopic lobectomy. This study was registered in the Chinese Clinical Trial Registry (ChiCTR-IPR-17011249) on April 27, 2017.  相似文献   
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Autocrine motility factor (AMF) is internalized via a receptor-mediated, dynamin-dependent, cholesterol-sensitive raft pathway to the smooth endoplasmic reticulum that is negatively regulated by caveolin-1. Expression of AMF and its receptor (AMFR) is associated with tumor progression and malignancy; however, the extent to which the raft-dependent uptake of AMF is tumor cell-specific has yet to be addressed. By Western blot and cell surface fluorescence-activated cell sorter (FACS) analysis, AMFR expression is increased in tumorigenic MCF7 and metastatic MDA-231 and MDA-435 breast cancer cell lines relative to dysplastic MCF10A mammary epithelial cells. AMF uptake, determined by FACS measurement of protease-insensitive internalized fluorescein-conjugated AMF, was increased in MCF7 and MDA-435 cells relative to MCF-10A and caveolin-1-expressing MDA-231 cells. Uptake of fluorescein-conjugated AMF was dynamin-dependent, methyl-beta-cyclodextrin- and genistein-sensitive, reduced upon overexpression of caveolin-1 in MDA-435 cells, and increased upon short hairpin RNA reduction of caveolin-1 in MDA-231 cells. Tissue microarray analysis of invasive primary human breast carcinomas showed that AMFR expression had no impact on survival but did correlate significantly with expression of phospho-Akt. Phospho-Akt expression was increased in AMF-internalizing MCF7 and MDA-435 breast carcinoma cells. AMF uptake in these cells was reduced by phosphatidylinositol 3-kinase inhibition but not by regulators of macropinocytosis such as amiloride, phorbol ester, or actin cytoskeleton disruption by cytochalasin D. The raft-dependent endocytosis of AMF therefore follows a distinct phosphatidylinositol 3-kinase-dependent pathway that is up-regulated in more aggressive tumor cells.  相似文献   
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