Time filter

Source Type

Tehrān, Iran

Farnia P.,Shahid Beheshti University | Farnia P.,The Republican Research and Practical Center for Epidemiology and and Microbiology | Farnia P.,University Putra Malaysia | Masjedi M.R.,Shahid Beheshti University | And 16 more authors.
International Journal of Clinical and Experimental Medicine | Year: 2010

The ultra-structure of Mycobacterium tuberculosis (MTB) was examined by transmission electronic (TEM)) and atomic force microscopy (AFM). The study was performed to describe the morphology of susceptible, multidrugresistant (MDR), extensively drug-resistant (XDR) and extremely drug-resistant tuberculosis isolates (XXDR-TB) during their exponential growth phase. Four types of cell division were observed and described. While three of them (symmetrical, asymmetrical and branching type) occurred in all isolates studied, the fourth one (adapted type) was seen only in XDR and XXDR-TB bacilli. In the fourth type of cell division, a rod shaped mother cell produced a small round shape bacillus (0.3-0.5 μm). These round cells were different from buds or polar division, but similar to terminal endospores without showing the typing heat resistance. Based on the present observation, we suggest that XDRand XXDR-TB bacilli accommodate changes helping them to overcome the hostile environment. Viewed under AFM, the other frequently detected shapes in MTB isolates were oval, V, Y and multi-branching filaments. These shape variation confirmed pleomorphic phenomena in MTB populations and the specific features of pan-resistant strains.

Moohebati M.,Mashhad University of Medical Sciences | Moohebati M.,University of Sfax | Bidmeshgi S.,Mashhad University of Medical Sciences | Azarpazhooh M.R.,University of Sfax | And 15 more authors.
Clinical Biochemistry | Year: 2011

Objective: This study aimed to evaluate the effects of statin therapy on serum levels of antibodies to several specific heat shock proteins (HSPs) in dyslipidemic patients. Design and methods: Participants (n= 102) were treated with simvastatin (40. mg/day), or placebo in a randomized, double-blind, placebo-controlled, cross-over trial. Anti-HSP60, 65, 70, and hs-CRP levels were measured before and after each treatment period. Seventy-seven subjects completed the study. Results: Treatment with simvastatin was associated with significant reductions in serum anti-HSP60, 65, and 70 titers in the dyslipidemic patients (10%, 14%, and 15% decrease, respectively) (p< 0.001). There have been previous reports of reductions in serum CRP with statin treatment, and although median CRP levels were 9% lower on simvastatin treatment, this did not achieve statistical significance. Conclusion: While it is unclear whether HSP antibodies are directly involved in atherogenesis, our findings suggest that simvastatin inhibits autoimmune responses that may contribute to the development of cardiovascular disease. © 2010 The Canadian Society of Clinical Chemists.

Pourghadamyari H.,Mashhad University of Medical Sciences | Moohebati M.,Mashhad University of Medical Sciences | Moohebati M.,University of Sfax | Parizadeh S.M.R.,University of Sfax | And 16 more authors.
Cell Stress and Chaperones | Year: 2011

Antibody titers to several heat shock proteins (anti-Hsps) have been reported to be associated with the severity and progression of cardiovascular disease. However, there are little data regarding anti-Hsp27 titers in patients with coronary artery disease (CAD). A total of 400 patients with suspected CAD were recruited. Based on the results of coronary angiography, these patients were classified into CAD+(n=300) and CAD-(n=100) groups defined as patients with ≥50% and <50% stenosis of any major coronary artery, respectively. Eighty-three healthy subjects were also recruited as the control group. Serum anti-Hsp27 IgG titers were measured using an in-house enzyme-linked immunosorbent assay. CAD+ patients had significantly higher anti-Hsp27 titers compared with both CAD- and control groups. Anti-Hsp27 titers were also higher in the CAD- group compared with the control group. With regard to the number of affected vessels in the CAD + group, patients with three-vessel disease had higher anti-Hsp27 titers compared with both two-vessel disease (2VD) and one-vessel disease (1VD) subgroups. However, there was no significant difference between 1VD and 2VD subgroups. In multiple linear regression analysis, the number of narrowed vessels and smoking were significant independent determinants of serum anti-Hsp27 titers. The present findings indicate that serum anti-Hsp27 titers may be associated with the presence and severity of coronary artery disease. © 2010 Cell Stress Society International.

Sardari S.,Pasteur Institute and 69 | Kohanzad H.,Deputy of Research | Ghavami G.,Pasteur Institute and 69 | Ghavami G.,A+ Network
Chemometrics and Intelligent Laboratory Systems | Year: 2014

Tuberculosis has become a serious condition with an estimated 2million deaths each year in the world. According to WHO report, multi-resistant tuberculosis is responsible for approximately 460 thousand recent cases per year and for about 740 thousand patients infected by both Mycobacterium tuberculosis and HIV/AIDS. In the current study, several bioactive structure databases were analyzed using cheminformatics tools to correlate the chemical structures of different compounds with their pharmacological activities; in addition, these tools were tried to identify molecules that could be candidate for experimental assays. In this regard, for defining the effective chemical compounds against Mycobacterium, a database consisting of 400 antimycobacterial compounds has been constructed. In the next step, more than 1400 molecular descriptors were defined by DRAGON application server for each compound. Then, the resulting descriptors were clustered by kNN and k-means clustering methods to be employed for ANN modeling. Utilizing PLS and ANN modeling methods led to building a model for predicting minimum inhibitory concentration (MIC) with R2=0.98 and MSE=0.0002. Applying the mentioned cheminformatics tools, it would be possible to design and introduce new compounds with broad applications in antimycobacterial drug discovery and development. © 2013 Elsevier B.V.

Najari A.,Collective Health | Yousefvand M.,Deputy of Research
Iranian Journal of Public Health | Year: 2013

Background: This study represents scientific production of Iran in medical sciences field at recent years, and the cor-relation between scientific productions with the number of indexed journals. Methods: Data extracted from SCOPUS database between years 2000 and 2011, and Iran's performance measured in terms of different Scientometrics indexes including self-citations, percent of cited articles, number of articles with in-ternational collaboration and contribution of Iran in medical sciences in Middle East and world. Moreover correlation between the number of articles, citations, self-citations, and H-index and number of indexed journals for 50 countries in all fields is included. Results: In 2011 year, Iran contributed 32.77 percent of the Middle East, and accounted for 1.57 percent of the world scientific production. The most frequent document type was original journal article published in English. Retrieved records revealed preferred subject areas, including medicine miscellaneous (14.53 percent of Iran publications in 2011 year). In 2011, according to the number of articles and citations to them, Iran was at 17th and 23th position between 226 countries, respectively. After adjustment for 19708 journals from 50 countries, Iran's rank based on the number of journals in medical sciences was 24th. Conclusion: The number of indexed journals with number of articles, citations, self-citations, and H-index of each country showed significant correlation (P-value<0.01). In recent years, by favoring quality over quantity of researches, the new rules have proven to be more effective for discriminating Iranian scientific productions.

Discover hidden collaborations