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The 32-base pair deletion on the C–C chemokine receptor 5 gene (CCR5-delta32) is known as a protective allele against immune system disorders. We have studied this variation in Iranian multiple sclerosis (MS) patients and healthy controls. DNA samples were prepared from the whole blood of 254 patients with MS and 380 healthy controls. We amplified the fragment including the CCR5-delta32 polymorphism and visualized the products in a documentation system after agarose gel electrophoresis. Data were analysed using one-way ANOVA and Fisher’s exact tests with SPSS-v13 and STATA-v8 software. The delta32 allele was more frequent in MS patients when compared with controls (OR = 2.3, P < 0.0001). Also, we found a significant difference in the frequency of the delta32/delta32 genotype among patients and controls (OR = 7.4, P < 0.001). The mean age at onset and progression index was not significantly different between patients with various genotypes. According to our study, the delta32 allele of the CCR5 gene might be a predisposing factor for MS development in the Iranian population. However, there were no associations between this polymorphism and the clinical course of the disease in this study.  相似文献   
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Bacterial meningitis continues to be associated with high morbidity and mortality rate worldwide, especially in the pediatric age group. This study was performed to identify the microbial etiologies of meningitis among 31 children, who were admitted in the Emergency Ward of a referral pediatric hospital in Iran. Culture identification showed that Streptococcus pneumoniae (12 subjects), Haemophilus influenzae (11 subjects) were the most common bacteria, followed by Escherichia coli (7 cases) and Neisseria meningitidis (only one case). Antibiotic susceptibility tests revealed that vancomycin had the best effect on S. pneumoniae in comparison with other antibiotics, whereas H. influenzae and E. coli were more susceptible to ceftriaxone, ceftazidime, and ceftizoxime than other antibiotics. In conclusion, despite the advances in antibiotic therapy and vaccine development, bacterial meningitis still is a health problem. S. pneumoniae, H. influenzae, and N. meningitidis are the main sources of bacterial meningitis, but other organisms such as E. coli should also be suspected, when a case is admitted to a referral pediatric hospital.  相似文献   
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Molecular Biology Reports - Vinblastine and vincristine are two important anti-cancer drugs that are synthesized by the Terpenoid Indole Alkaloids (TIAs) pathway in periwinkle (Catharanthus...  相似文献   
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Aminoglycoside antibiotics are widely used against Gram‐negative infections. On the other hand, nephrotoxicity is a deleterious side effect associated with aminoglycoside therapy. Gentamicin is the most nephrotoxic aminoglycoside. Because of serious health complications ensue the nephrotoxicity induced by aminoglycosides, finding new therapeutic strategies against this problem has a great clinical value. This study has attempted to compare the nephrotoxic properties of gentamicin and a new nanosized formulation of this drug in a mice model. Animals were treated with gentamicin (100 mg/kg, i.p. for eight consecutive days) and nanogentamicin (100 mg/kg, i.p. for eight consecutive days). Blood urea nitrogen (BUN), plasma creatinine levels, and histopathological changes of kidney proximal tubule were monitored. It was found that gentamicin caused severe degeneration of kidney proximal tubule cells and an increase in serum creatinine and BUN. No severe injury was observed after nanogentamicin administration. This study proved that nanosized gentamicin is less nephrotoxic.  相似文献   
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Background

Breast cancer is one of the most common cancers among women throughout the world. Therefore, established cell lines are widely used as in vitro experimental models in cancer research.

Methods

Two continuous human breast cell lines, designated MBC1 and MBC2, were successfully established and characterized from invasive ductal breast carcinoma tissues of Malaysian patients. MBC1 and MBC2 have been characterized in terms of morphology analysis, population doubling time, clonogenic formation, wound healing assay, invasion assay, cell cycle, DNA profiling, fluorescence immunocytochemistry, Western blotting and karyotyping.

Results

MBC1 and MBC2 exhibited adherent monolayer epithelial morphology at a passage number of 150. Receptor status of MBC1 and MBC2 show (ER+, PR+, HER2+) and (ER+, PR-, HER2+), respectively. These results are in discordance with histopathological studies of the tumoral tissues, which were triple negative and (ER-, PR-, HER2+) for MBC1 and MBC2, respectively. Both cell lines were capable of growing in soft agar culture, which suggests their metastatic potential. The MBC1 and MBC2 metaphase spreads showed an abnormal karyotype, including hyperdiploidy and complex rearrangements with modes of 52–58 chromosomes per cell.

Conclusions

Loss or gain in secondary properties, deregulation and specific genetic changes possibly conferred receptor changes during the culturing of tumoral cells. Thus, we hypothesize that, among heterogenous tumoral cells, only a small minority of ER+/PR+/HER2+ and ER+/PR-/HER2+ cells with lower energy metabolism might survive and adjust easily to in vitro conditions. These cell lines will pave the way for new perspectives in genetic and biological investigations, drug resistance and chemotherapy studies, and would serve as prototype models in Malaysian breast carcinogenesis investigations.  相似文献   
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Plasmonics - In this paper, a graphene-based patch antenna is proposed. The antenna structure is designed so that each of the various antenna sections affected by chemical potential changes can...  相似文献   
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There are many published studies presenting ethanol and acetone as PHAs‐poor solvents, where these two solvents are shown to dissolve <2% (w/v) of PHAs at low temperatures. In this study, the suitability of ethanol and acetone for the recovery of PHB at different temperatures (from room temperature to near boiling point) in Cupriavidus necator was investigated. Experiments were performed using response surface methodology to examine the effects of different temperatures and heating incubation times on recovery percentage using the two solvents. The highest recovery percentage (92.3%) and product purity (up to 99%) were obtained with ethanol‐assisted extraction at 76°C for 32 min of incubation time. Under these conditions the extracted PHB exhibited a molecular mass of 1.2 × 106. The present strategy showed that at temperatures near its boiling point, ethanol, as a nonhalogenated solvent, represents a good alternative to halogenated solvents, like chloroform, when PHB recovery is concerned. DSC analysis showed good thermal properties for ethanol‐ and acetone‐extracted biopolymers. GC and 1H NMR analysis confirmed the extracted biopolymer to be polyhydroxybutyrate of good purity. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1480–1486, 2016  相似文献   
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