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41.
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Multidrug-resistant tuberculosis (MDR-TB) is caused by bacteria that are resistant to the most effective anti TB drugs (Isoniazid and Rifampicin) with or without resistance to other drugs. Novel intervention strategies to eliminate this disease based on finding proteins can be used for designing new drugs or new and reliable kits for diagnosis. The aim of this study was to compare the protein profile of MDR-TB with sensitive isolates. Two-dimensional gel electrophoresis (2DE) along with mass spectrometry is a powerful and effective tool to identification and characterization of Mycobacterium tuberculosis. Two-dimensional gel electrophoresis and matrix assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry was used for diagnosis and comparison of proteins. We identified 14 protein spots in MDR-TB isolates that 2DE analysis showed these spots absent in M. tuberculosis sensitive isolates (Rv1876, Rv0379, Rv0147, Rv2031c, Rv3597c, Rv1886c, MT0493, Rv0440, Rv3614c, Rv1626, Rv0443, Rv0475, Rv3057 and unknown protein. The results showed 22 protein spots which were up regulated (or expressed) by the MDR-TB isolates, (Rv1240, Rv3028c, Rv2971, Rv2114c, Rv3311, Rv3699, Rv1023, Rv1308, Rv3774, Rv0831c, Rv2890c, Rv1392, Rv0719, Rv0054, Rv3418c, Rv0462, Rv2215, Rv2986c, Rv3248c and Rv1908c)). Two up regulated protein spots were identified in sensitive isolate (Rv1133c and Rv0685). These data will provide valuable clues in further investigation for suitable TB rapid tests or drug targets against drug resistant and sensitive of M. tuberculosis.  相似文献   
43.
An association between a hypercoagulable state and Mendelian susceptibility to mycobacterial disease (MSMD) has been established in a few studies; resultant thrombosis is considered rare. In a case‐control study, the prevalence of factor V Leiden, prothrombin G20210A and methylenetetrahydrofolate reductase (MTHFR) C677T, A1298C mutations were investigated in mycobacterium‐infected patients. The study comprised 30 patients with mycobacterial infections (invasive, disseminated and/or recurrent infections with Bacille Calmette–Guerin or non‐tuberculosis mycobacteria and Mycobacterium Tuberculosis with positive results for acid‐fast bacilli and tuberculin skin tests) and 30 normal healthy controls. Forty female (66.7%) and 20 male subjects (33.3%) aged from 3 to 70 years were recruited into this study. Genotyping of targeted genes was performed by RT‐PCR and cytokine TNF‐α concentrations were quantified using a commercially available ELISA kit. Significant associations between mycobacterial infection and TNF‐α production after stimulating peripheral blood mononuclear cells with LPS alone and with IFN‐γ plus LPS were identified. Moreover, genotyping analysis in the studied population revealed a significant association between MTHFR c.677C>T (OR, 3.28; 95% CI, 1.35–7.92; P < 0.05), MTHFR c.1298A>C (OR, 2.33; 95% CI, 1.10–4.93; P < 0.05) and mycobacterial infection in affected patients, indicating susceptibility to venous thromboembolism according to previous studies. Additionally, mycobacterium‐infected patients had a significantly greater prevalence of MTHFR C677T and A1298C mutations than controls.  相似文献   
44.
Hepatocellular carcinoma (HCC) is known as one of the major health problems worldwide. Pathological analysis indicated that a variety of risk factors including genetical (i.e., alteration of tumor suppressors and oncogenes) and environmental factors (i.e., viruses) are involved in beginning and development of HCC. The understanding of these risk factors could guide scientists and clinicians to design effective therapeutic options in HCC treatment. Various viruses such as hepatitis B virus (HBV) and hepatitis C virus (HCV) via targeting several cellular and molecular pathways involved in HCC pathogenesis. Among various cellular and molecular targets, microRNAs (miRNAs) have appeared as key players in HCC progression. miRNAs are short noncoding RNAs which could play important roles as oncogenes or tumor suppressors in several malignancies such as HCC. Deregulation of many miRNAs (i.e., miR-222, miR-25, miR-92a, miR-1, let-7f, and miR-21) could be associated with different stages of HCC. Besides miRNAs, exosomes are other particles which are involved in HCC pathogenesis via targeting different cargos, such as DNAs, RNAs, miRNAs, and proteins. In this review, we summarize the current knowledge of the role of miRNAs and exosomes as important players in HCC pathogenesis. Moreover, we highlighted HCV- and HBV-related miRNAs which led to HCC progression.  相似文献   
45.
Rheumatoid arthritis (RA) is an autoimmune disease, pathologically characterized by lymphocyte infiltration of the synovial membrane that leads to chronic inflammation and progressive joint damage. RA develops as a result of increased cell infiltration and cell proliferation as well as impaired cell death. Activated cells in joints including lymphocytes and fibroblast-like synoviocytes (FLS) survive for a long time as a consequence of compromised apoptosis, but the mechanism underlying cell survival in synovium remains to be firmly established. Inhibition of apoptosis by survivin, as a critical antiapoptotic protein, contributes to both the persistence of autoreactive T lymphocytes and tumor-like phenotype of FLS in RA. In addition to the antiapoptotic role, survivin also has prognostic relevance in RA prodromal phase. Hence, this review provides an overview of the current knowledge regarding the involvement of survivin protein in the pathogenesis of RA.  相似文献   
46.
Molecular Biology Reports - Metabolic syndrome (MetS) is associated with a pro-inflammatory state and endothelial dysfunction that places subjects with MetS at a higher risk of atherosclerosis....  相似文献   
47.
Background:Prostate cancer (PC) is one of the most abundant cancers among men, and In Iran, has been responsible for 6% of all deaths from cancer in men. NUF2 and GMNN genes are considered as loci of susceptibility to tumorigenesis in humans. Alterations in expression of these genes have been reported in various malignancies. The aim of our study was to test whether different NUF2 and GMNN expression levels are associated with PC incidence and hence, might be considered as new molecular tools for PC screening.Methods:Biopsy samples from 40 PC patients and 41 healthy Iranian men were used to determine the relative gene expression. After RNA extraction and cDNA synthesis, samples were analyzed using TaqMan Quantitative Real time PCR. Patients’ background information, included smoking habits and family histories of PC, were recorded. Stages and grades of their PC were classified by the TNM tumor, node, metastasis (TMN) staging system based on standard guidelines.Results:NUF2 expression did not significantly differ between the groups, while GMNN expression was significantly greater in the PC specimens than in the controls.Conclusion:Regarding the significant role of GMNN in various tumor phenotypes, and its importance in PC progression, the alteration in GMNN expression in PC samples vs. controls indicate that the genetic profiling of this cancer might be considered to personalize therapy for each patient in the future.Key Words: Family history, Geminin (GMNN), Tumor staging, NUF2, Prostate cancer  相似文献   
48.
Molecular Biology Reports - Breast Cancer is the most frequent neoplasm diagnosed among women worldwide. Genetic background and lifestyle/environment play a significant role in the disease...  相似文献   
49.
An in vitro cell suspension culture of Echium italicum was established and assayed for the production of shikonin and alkannin derivatives. Callus tissues were induced from cotyledon explants of the plant incubated onto the solidified B5 medium. A two-liquid-phase system suspension culture was then established to elicit pigments of shikonin and alkannin derivatives using liquid paraffin. The presence of liquid paraffin efficiently induced production of pigments in cultured cells. The production and/or accumulation of these compounds in the E. italicum cells was examined using fluorescence microscopy as the naphthoquinone molecules display autofluorescent properties. Phytochemical analysis of the n-hexane extract of the medium was also carried out using preparative HPLC. The chemical structure of shikonin and alkannin derivatives were characterized by UV, 1H-NMR, and 13C-NMR techniques. Based on our findings, this bioprocess engineering approach resulted in induction of shikonin and alkannin derivatives, whereupon it may be recruited for production of these important secondary metabolites.  相似文献   
50.
Allothrombium clavatum sp. n. with reduced inner claw of tarus III, one seta on coxa II, clavate dorsal idiosomal setae and 3-lobed posterior margin of scutum, collected as ectoparasite of an undetermined aphid, is described and illustrated from the central part of Montenegro (Balkan Peninsula). A key to world species of Allothrombium (larva) is presented.  相似文献   
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