18 research outputs found
Genetic relatedness among isolates of Shigella sonnei carrying class 2 integrons in Tehran, Iran, 2002–2003
<p>Abstract</p> <p>Background</p> <p><it>Shigella </it>spp. are major cause of diarrhoeal disease in both developing and developed countries. <it>Shigella sonnei </it>is the serogroup of <it>Shigella </it>most frequently responsible for sporadic and epidemic enteritis in developed countries. In recent years the emergence and spread of <it>S. sonnei </it>biotype g carrying class 2 integron have been frequently reported in many countries. Recently, <it>S. sonnei </it>has been reported as the prevalent serogroup of <it>Shigella </it>in Iran.</p> <p>The present study was carried out to investigate phenotypic and genetic characteristics of <it>Shigella sonnei </it>isolates identified in the years 2002 and 2003 in Tehran, Iran.</p> <p>Methods</p> <p>Biotyping, drug susceptibility testing, pulsed field gel electrophoresis (PFGE) and analysis of class 2 integrons have been carried out on 60 <it>S. sonnei </it>isolates, including 57 sporadic isolates from paediatric cases of shigellosis occurring in 2002 and 2003, two sporadic isolates recovered in 1984 and the ATCC 9290 strain.</p> <p>Results</p> <p>Biotype g and resistance to streptomycin, sulfamethoxazole-trimethoprim and tetracycline were exhibited by 54 of the 57 recent isolates. Of the 54 biotype g isolates, 28 exhibited a class 2 integron of 2161 bp, and 24 a class 2 integron of 1371 bp, respectively. Class 2 integrons were not detected in four isolates only, including the two endemic isolates recovered in 1984 and two strains from recent sporadic cases. PFGE divided the strains into eight pulsotypes labeled A to H, three major pulsotypes – A to C – including the large majority of the recent sporadic <it>S. sonnei </it>isolates. Pulsotypes A and C were the most prevalent groups, accounting for 41.6% and 35.0%, respectively, of the isolates under study.</p> <p>Conclusion</p> <p>The results suggest that biotype g, class 2 integron carrying <it>S. sonnei </it>are prevalent in our geographic area. <it>S. sonnei </it>isolated in the years 2002 and 2003 could be attributed to a few predominant clusters including, respectively, strains with pulsotypes B and C carrying a 2161 bp class 2 integron, and those having pulsotype A and a 1371 bp class 2 integron. A few epidemic clones are responsible for the apparently endemic occurrence of shigellosis in Tehran, Iran.</p
Goat and buffalo milk fat globule membranes exhibit better effects at inducing apoptosis and reduction the viability of HT-29 cells
Bovine milk fat globule membrane (MFGM) has shown many health benefits, however, there has not been much study on non-cattle MFGMs. The purpose of this study was to compare the anti-proliferation effects and investigate the mechanisms of MFGMs from bovine, goat, buffalo, yak and camel milk in HT-29 cells. Results showed that protein content in MFGM of yak milk is the highest among five MFGM. All MFGMs inhibited cellular proliferation which was in agreement with cell morphology and apoptosis. However, the number of cells in S-phase from 24 h to 72 h was increased significantly by treatment with goat, buffalo and bovine MFGMs (100 μg/mL), but not yak and camel. All MFGMs treatment significantly reduced the mitochondrial membrane potential (with an order of goat>buffalo>bovine>camel>yak) and Bcl-2 expression, but increased the expression of both Bax and Caspase-3. Taken together, the results indicate that all MFGMs, especially goat and buffalo MFGMs, showed better effects at inducing apoptosis and inhibition of the proliferation of HT-29 cells. The mechanism might be arresting the cell cycle at S phase, depolarization of mitochondrial membrane potential, down-regulation of Bcl-2 expression and increase of Bax and Caspase-3 expression
New species of endophytic fungi from grapevine (Vitis vinifera) in Iran
During the study on endophytic fungi of grapevine (Vitis vinifera L.), 655 fungal isolates were obtained and
studied taxonomically. Based on morphological and ITS sequences data, 15 species belonging to 10 genera including
Alternaria brassicicola, A. chlamydospora, A. malorum, A. atra, Arthrinium phaeospermum, A. sacchari, Aspergillus
nidulans, A. wentii, Beauveria bassiana, Cheatomium elatum, Epicoccum nigrum, Geosmithia pallida, Paecillomyces
variotii, Cytospora punicae, and Verrucobotrys geranii are introduced as endophytic fungi of grapevine. Grapevineis as
matrix nova for all mentioned species in Iran. Also, all identified species except A. phaeospermum, B. bassiana, and
E. nigrum are reported for the first time as endophytic fungi of grapevine worldwide. Four species viz. A. sacchari,
C. punicae, G. pallid, and V. geranii are introduced and described for the first time from Iran
Obesity measures and elevated levels of alanine aminotransferase: A population based study
Background: Obesity may lead to various morbidity including liver diseases. The present study was done to determine which obesity indices, including body mass index (BMI), waist circumference (WC), waist to hip ratio (WHR), and waist to height ratio (WHtR) have the stronger association with rising levels of alanine aminotransferase (ALT). Materials and Methods: Of 6143 subjects aged � 10 years of a cohort study in northern Iran, the data of 5052 subjects were analyzed. We performed multivariate logistic regression analyses for data of men and women, separately. In multivariate analyses the obesity measures were separately included in model in addition to other potential confounders. A high value of ALT was considered as outcome. The capability of obesity indices to discriminate an elevated level of ALT was evaluated using receiver operating characteristic (ROC). Results: Based on our results, men and women with obesity showed significantly higher values of liver enzymes for all obesity indices. In multivariate analysis, while WHtR showed the strongest association with a high value of ALT in men Wald=91.44; OR=3.348, 95%CI (2.613-4.289); P<0.001, WC showed the strongest association in women Wald=26.76; OR=1.724, 95%CI (1.402-2.119). Conclusion: WHtR in men and WC in women have more independent association with elevated levels of ALT
South-East Asia is the center of origin, diversity and dispersion of the rice blast fungus, Magnaporthe oryzae
BGPI : équipe 5International audienceInferring invasion routes and identifying reservoirs of diversity of plant pathogens are essential in proposing new strategies for their control. Magnaporthe oryzae, the fungus responsible for rice blast disease, has invaded all rice growing areas. Virulent genotypes regularly (re) emerge, causing rapid resistance breakdowns. However, the world-wide genetic subdivision of M. oryzae populations on rice and its past history of invasion have never been elucidated. In order to investigate the centers of diversity, origin and migration of M. oryzae on rice, we analyzed the genetic diversity of 55 populations from 15 countries. Three genetic clusters were identified world-wide. Asia was the center of diversity and the origin of most migrations to other continents. In Asia, two centers of diversity were revealed in the Himalayan foothills: South China–Laos–North Thailand, and western Nepal. Sexual reproduction persisted only in the South China–Laos–North Thailand region, which was identified as the putative center of origin of all M. oryzae populations on rice. Our results suggest a scenario of early evolution of M. oryzae on rice that matches the past history of rice domestication. This study confirms that crop domestication may have considerable influence on the pestification process of natural enemies