266 research outputs found
Genetic diversity of Azotobacter strains isolated from soils by amplified ribosomal DNA restriction analysis
Strains of Azotobacter mediate in the nitrogen fixation process by reducing of N2 to ammonia. In this study, 50 strains were isolated from different rhizospheric soil in central Iran, by using soil paste-plate method. These strains were biochemically identified and characterized on differential LG medium based on morphological and physiological properties. Results obtained showed that identified strains were belonging to three species, namely A. chroococcum, A. vinelandii and A. beijernckii. In order to molecular analysis, the 16S rRNA gene was amplified using 27f and 1495r primers and PCR products were subsequently restricted with RsaI, HpaII and HhaI. Cluster analysis based on amplified ribosomal DNA restriction analysis were revealed intraspecific polymorphism and differentiated strains into two mains clusters, clusters A and B. Cluster A strains were related to the A. vinelandii, whereas cluster B strains were related to the A. chroococcum and A. beijerinckii. The results show that amplified ribosomal DNA restriction analysis is a powerful and discriminatory tool for the identification of members of the genus Azotobacter.Штаммы Azotobacter являются посредниками в проессах фиксации азота, восстанавливая N2 до аммония. Из разных ризосферных почв Ирана выделено 50 штаммов. Эти штаммы биохимически идентифицированы и охарактеризованы на дифференциальной среде LG на основе морфологических и физиологических свойств. Полученные результаты показали, что идентифицированные штаммы принадлежат трем видам – A. chroococcum, A. vinelandii и A. beijerinckii. Для молекулярного анализа ген 16S рРНК был амплифицирован с использованием 27f и 1495r праймеров, а продукты ПЦР расщеплены с помощью RsaI, HpaII и HhaI. Кластерный анализ, основанный на рестрикционном анализе амплифицированных рибосомальных ДНК (ARDRA), показал межвидовой полиморфизм и разделение штаммов на два основных кластера, A и B. Линии кластера А относятся к A. vinelandii, а кластера В – к A. chroococcum и A. beijerinckii. Результаты показывают, что ARDRA является эффективным методом идентификации видов рода Azotobacter.We would like to express our special gratitude to Dr. M. Khosroshahli (Department of biotechnology) for his helpful support. This work was supported by Islamic Azad University, Science and Research Branch, Tehran, Iran
Screening of some Zygomycetes for cellulase activity
This study was aimed to screen the cellulytic ability of some genera of Zygomycetes under laboratory conditions. Carboxy methyl cellulose (CMC) and Wheat straw (WS) were used as the only carbon source in a minimal culture medium. Four days after inoculation, released proteins and sugars were assayed with related reagents and repeated each, 3 days up to the 31th day. Statistical analysis showed significant variation in released sugars but no significant variation in released proteins among tested genera. Mucor hiemalis f. corticola had highest and Mucor circinelloides f. circinelloides had lowest sugar levels. Glucose levels for M. hiemalis f. corticola increased until 16 days after inoculation, then decreased until 25th day, but had no variation until 30th day. These results showed that isolates belonging to the same forms had no significant difference in cellulase activity, but the ability of different genera and species were noticeable. This study also showed that WS medium can be effectively used for cellulase production by fungi
Coenzyme Q10 in the treatment of heart failure: A systematic review of systematic reviews
Introduction: This article is an attempt to provide an overview of systematic reviews to determine the efficacy of CQ10 supplementation in the treatment of patients with cardiovascular diseases (CVD). Method and material: All reviews were identified through a systematic search of the following databases: Cochrane, DARE, Ovid, EMBASE, ISI Web of Knowledge, and PubMed. Check references studies and the quality of the studies was assessed by means of AMSTTAR. No meta-analyses were performed due to the heterogeneity of studies. Result: Extracted data for Seven systematic reviews for primary outcomes, net changes in cardiac output, cardiac index, New York Heart Association functional classification, improved survival, based on existing evidence, there is a case for use of CoQ10 as an adjunctive therapy in congestive heart failure, especially in those patients unable to tolerate mainstream medical therapies. Conclusion: Evidence suggests that the CoQ10 supplement may be a useful tool for managing patients with heart failure. © 201
Coenzyme Q10 in the treatment of heart failure: A systematic review of systematic reviews
Introduction: This article is an attempt to provide an overview of systematic reviews to determine the efficacy of CQ10 supplementation in the treatment of patients with CVD. Method and material: All reviews were identified through a systematic search of the following databases: Cochrane, DARE, Ovid, EMBASE, ISI Web of Knowledge, and PubMed. Check references studies and the quality of the studies was assessed by means of AMSTTAR. No meta-analyses were performed due to the heterogeneity of studies. Result: Extracted data for Seven systematic reviews for primary outcomes, net changes in cardiac output, cardiac index, New York Heart Association functional classification, improved survival, based on existing evidence, there is a case for use of CoQ10 as an adjunctive therapy in congestive heart failure, especially in those patients unable to tolerate mainstream medical therapies. Conclusion: Evidence suggests that the CoQ10 supplement may be a useful tool for managing patients with heart failure. © 2018
Interactive effects of Arbuscular mycorrhizal fungi and rhizobial strains on chickpea growth and nutrient content in plant
Legumes form a tripartite symbiosis with Arbuscular mycorrhizal fungi (AMF) and rhizobia. Chickpea plants were inoculated with six strains of Mesorhizobium ciceri and three AMF species, Glomus intraradices (GI), G. mosseae (GM) and G. etunicatum (GE). The plants inoculated with a number of AMF species and bacterial strains increased overall plant dry mass compared to non-inoculated plants. GE was the most efficient in increasing plant dry matter. Individual AMF species were more effective than when mixed (GI+GM+GE). Bacterial treatments had increasing effect on root colonization by GI, GM and GI+GM+GE. The results revealed that dual inoculation with AMF and rhizobium enhanced nitrogen, phosphorus, zinc, iron and copper content in plants but these increasing effects was different between fungal and bacterial treatments.Key words: Arbuscular mycorrhizal fungi, Mesorhizobium ciceri, nutrient content, root colonization, nodule, chickpea
Nitric oxide metabolite levels during the ectopic osteoinduction in rats
Abstract Nitric oxide (NO) is a cell-signaling molecule
that has diverse biological functions. Recent evidence
suggests that its production may regulate the metabolism
of the osteoblasts and osteoclasts. The aim of this study was
to evaluate levels of nitrite and nitrates (NO metabolites)
during ectopic osteoinduction in rats. Eighteen male
Sprague–Dawley rats (body weight 200–300 g) were used
in this study. All animals were anesthetized and the right
and left flank areas were shaved, and under aseptic
conditions, a muscular pouch was created in each flank:
the left was filled with 20 mg of demineralized bone matrix
and the right remained empty (sham). Radiographs were
taken at 2, 4, and 6 weeks after surgery to trace the ectopic
bone formation and muscle mineralization. Blood samples
were taken before (as baseline values) and at 2, 4, and
6 weeks after surgery. The mean values of NO metabolites
after 6 weeks were significantly higher (p<0.05) than
baseline data and at 2 weeks post-surgery. Results from this
study indicate that the ectopic osteoinduction caused
increased activity of the osteoblasts which subsequently
caused increased serum levels of NO metabolites (nitrites
and nitrates)
Optimal, scalable forward models for computing gravity anomalies
We describe three approaches for computing a gravity signal from a density
anomaly. The first approach consists of the classical "summation" technique,
whilst the remaining two methods solve the Poisson problem for the
gravitational potential using either a Finite Element (FE) discretization
employing a multilevel preconditioner, or a Green's function evaluated with the
Fast Multipole Method (FMM). The methods utilizing the PDE formulation
described here differ from previously published approaches used in gravity
modeling in that they are optimal, implying that both the memory and
computational time required scale linearly with respect to the number of
unknowns in the potential field. Additionally, all of the implementations
presented here are developed such that the computations can be performed in a
massively parallel, distributed memory computing environment. Through numerical
experiments, we compare the methods on the basis of their discretization error,
CPU time and parallel scalability. We demonstrate the parallel scalability of
all these techniques by running forward models with up to voxels on
1000's of cores.Comment: 38 pages, 13 figures; accepted by Geophysical Journal Internationa
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The impact of statin therapy on the survival of patients with gastrointestinal cancer
Statins are 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors that may play an important role in the evolution of cancers, due to their effects on cancer cell metabolism. Statins effect several potential pathways, including: cell proliferation, angiogenesis, apoptosis and metastasis. The number of trials assessing the putative clinical benefits of statins in cancer is increasing. Currently, there are several trials listed on the global trial identifier website clinicaltrials.gov. Given the compelling evidence from these trials in a variety of clinical settings, there have been calls for a clinical trial of statins in the adjuvant gastrointestinal cancer setting. However, randomized controlled trials on specific cancer types in relation to statin use, as well as studies on populations without a clinical indication for using statins, have elucidated some potential underlying biological mechanisms, and the investigation of different statins is probably warranted. It would be useful for these trials to incorporate the assessment of tumour biomarkers predictive of statin response in their design. This review summarizes the recent preclinical and clinical studies that assess the application of statins in the treatment of gastrointestinal cancers with particular emphasize on their association with cancer risk
EW-7197 prevents ulcerative colitis-associated fibrosis and inflammation
EW‐7197 is a transforming growth factor‐β type I receptor kinase inhibitor with potential anti‐inflammatory and antifibrotic properties. Here, we investigate the potential therapeutic effects of EW‐7197 in a murine model of ulcerative colitis. EW‐7197 attenuated the colitis disease activity index by improving rectal bleeding, body weight, and degree of stool consistency. EW‐7197 also reduced colorectal tissue damage and the colon histopathological score by reducing crypt loss, mucosal damage, and tissue inflammation. Moreover, EW‐7197 appeared to ameliorate the inflammatory and fibrotic responses by reducing oxidative stress, reducing submucosal edema and inflammatory cell infiltration, downregulating proinflammatory and pro‐fibrotic genes, and inhibiting excessive collagen deposition in inflamed and fibrotic ulcerative colitis tissues. These results suggest that EW‐7197 has potentially useful therapeutic properties against colitis, with clinically translational potential of inhibiting key pathological responses of inflammation and fibrosis in patients with colitis
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