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We report on a novel localization for a recessive form of deafness (DFNB), by linkage analysis in an Iranian consanguineous family. Affected individuals suffer from prelingual profound sensorineural hearing loss. Genome-wide analysis led to the characterization of a new locus, DFNB40, which maps to an approximately 9 Mb interval between markers D22S427 and D22S1144 at chromosome 22q11.21-12.1. Maximum lod score of 3.09 was obtained with D22S1174. Since the Bronx waltzer (bv) mouse mutant, characterized by waltzing behavior, deafness, and degeneration of cochlear inner hair cells, has been mapped to the syntenic region on murine chromosome 5, we suggest that DFNB40 and bv may result from orthologous gene defects.  相似文献   
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This paper examines the electrochemical and microstructural features of SrCo0.8Fe0.1Ga0.1O3−δ (SCFG) with a fibrous structure infiltrated by an SDC electrolyte for use as a cathode in solid oxide fuel cells (SOFCs). An electrospinning process is used to produce SCFG fibers. In a symmetrical cell, Sm0.2Ce0.8O1.9 (SDC) nanoparticles are infiltrated into the porous fibrous SCFG cathode layer after it was applied to the SDC dense electrolyte. Electrochemical impedance spectroscopy (EIS) analysis reveals that the polarization resistance of the SCFG cathode with fiber morphology is significantly lower than that of the same combination with powder morphology. In addition, it is shown that infiltration of SDC oxygen ion conductor nanoparticles enhanced electrochemical performance. The lowest value of polarization resistance, 0.03 Ω cm2 at 800 °C, is attained by the SCFG with a fibrous structure containing 14 wt% SDC nanoparticles.  相似文献   
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The present systematic review and meta‐analysis was conducted to investigate the effects of ginger supplementation on markers of inflammatory and oxidative stress. PubMed, Embase, Scopus, and Web of Science were systematically searched to identify relevant clinical trials evaluating the effects of ginger on serum CRP (C‐reactive protein), TNF‐α (tumor necrosis factor‐alpha), IL‐6 (interleukin‐6), PGE2 (prostaglandin E2), TAC (total antioxidant capacity), and MDA (malondialdehyde) from inception up to September 2019. Mean difference and 95% confidence intervals were pooled using a random‐effects model. Potential publication bias was assessed using visual inspection of funnel plot and Egger's weighted regression tests. After excluding irrelevant records, 20 full‐text articles that included 25 separate studies were included to the meta‐analysis. Pooled results of this study indicated a statistically significant effect of ginger on serum CRP, TNF‐α, IL‐6, TAC, and MDA levels following ginger supplementation in compared to the controls. Also, the effects of ginger on serum PGE2 was marginally significant. Moreover, the high heterogeneity was disappeared in subgroup analysis performed by age, duration, dosage, and quality. This current analysis indicates that ginger supplementation has a significant effects on serum inflammatory and oxidative stress markers.  相似文献   
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This investigation was conducted to evaluate the effect of deferasirox on selenium toxicity in male rat organs. After 50 days of selenium administration, all the rats showed toxicity symptoms. After poisoning, deferasirox was given orally to rats during 10 days. The results show that toxicity symptoms were unexpectedly increased. The new symptoms of toxicity after deferasirox administration were including loss of body hairs, yellowish discoloration of hair, weakness, brown spot on their skin, enlargement of the spleen and shrinking of sex organs. Selenium and iron concentrations were determined by GFAAS and FAAS, respectively. The results indicate the poisoned rats with selenium that received deferasirox as a drug, shown serious symptoms such as exacerbate toxicity, reduction in iron concentration, anemia and even death after a few days of deferasirox administration.  相似文献   
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Background: Interleukin 18 (IL-18) exerts pleiotropic roles in many inflammatory-related diseases including parasitic infection. Previous studies have demonstrated the promising therapeutic potential of modulating IL-18 bioactivity in various pathological conditions. However, its involvement during malaria infection has yet to be established. In this study, we demonstrated the effect of modulating IL-18 on the histopathological conditions of malaria infected mice. Methods: Plasmodium berghei ANKA infection in male ICR mice was used as a model for malaria infection. Modulation of IL-18 release was carried out by treatment of malarial mice with recombinant mouse IL-18 (rmIL-18) and recombinant mouse IL-18 Fc chimera (rmIL-18Fc) intravenously. Histopathological study and analysis were performed on major organs including brain, liver, spleen, lungs and kidney. Results: Treatment with rmIL-18Fc resulted in significant improvements on the histopathological conditions of the organs in malaria-infected mice. Conclusion: IL-18 is an important mediator of malaria pathogenesis and targeting IL-18 could prove beneficial in malaria-infected host.Key Words: Malaria, Interleukin-18, Plasmodium berghei, Histopathology  相似文献   
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Context: Vinoreline is a vinca alkaloid anticancer drug widely used in cancer therapy. Drugs are not target specific, therefore might affect normal tissues/cells, in which bone marrow is the important one. Objective: To elucidate the cytotoxic and genotoxic effect of vinca alkaloid anti cancer drug, vinorelbine, on mice non-adherent bone marrow cells in vitro. Materials and methods: Non-adherent bone marrow cells were isolated and exposed to various concentrations (0–160?µg/ml) for 4?h at 23?°C. The chromatin proteins were analyzed by SDS PAGE and western blot. Fluorescent dye staining of the cells, anion superoxide and DNA fragmentations assays were also employed. Result: The results from MTT and trypan blue exclusion assays represented reduction of the cells viability. Extractability of histones and HMG proteins contrasted with difficulty as their content was decreased on SDS-gel upon increasing drug concentration as western blots confirmed it. The amount of degradation form of PARP (89?KD) increased significantly in a dose dependent manner. Increase in anion superoxide production and DNA fragmentation together with cytological detection of chromatin condensation and cellular damage upon exposure of the cells to vinorelbine were indicative of apoptosis induction in these normal cells. Conclusion: Vinorelbine is genotoxic in non-adherent bone marrow cells as affects chromatin components, DNA, histone and HMGB1 proteins and induces apoptosis.  相似文献   
10.

Background and study aims

Helicobacter pylori (H. pylori) has been implicated in the pathogenesis of most important gastro-duodenal diseases, such as gastritis, peptic ulcer disease (PUD) and gastric cancer. H. pylori upregulates the expression and activity of several matrix metalloproteinases (MMPs) in the gastric mucosa, but the role of MMP-3 and MMP-9 in infected patients with H. pylori have not been clearly defined yet. We examined mucosal MMP-3 and MMP-9 mRNA levels in gastric mucosa of H. pylori infected patients and evaluated the effects of virulence factors cagA and vacA allelic variants on these levels. We also determined correlation between mucosal MMP-3 and MMP-9 mRNA levels and types of disease.

Patients and methods

Total RNA was extracted from gastric biopsies of 50 H. pylori-infected patients and 50 H. pylori-negative patients. Mucosal MMP-3 and MMP-9 mRNA expression level in H. pylori-infected and non-infected gastric biopsies were determined by real time-polymerase chain reaction (PCR). Presence of vacA (vacuolating cytotoxin A) and cagA (cytotoxin associated gene A) virulence factors were evaluated using PCR.

Results

The levels of MMP-3 in gastric mucosa were not different between H. pylori-positive and H. pylori-negative patients. There was no correlation between MMP-3 mRNA expression and virulence factor (cagA and vacA allelic variants) and the different types of disease (gastritis and PUD) in infected patients. But MMP-9 mRNA expression was significantly higher in biopsies of H. pylori-infected patients compared to H. pylori-negative patients. Also mucosal MMP-9 mRNA expression in H. pylori-infected patients was significantly associated with cagA status PUD.

Conclusion

Our results suggest that MMP-9 might be involved in the pathogenesis of H. pylori. PUD could be associated with cag PAI-dependent MMP-9 upregulation.  相似文献   
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