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991.
Yeganeh LP Azarbaijani R Sarikhan S Mousavi H Ramezani M Amoozegar MA Fazeli AS Salekdeh GH 《Journal of bacteriology》2012,194(8):2123-2124
Oceanimonas sp. GK1 (IBRC-M 10197) is a marine halotolerant gammaproteobacterium which was characterized as producing large amounts of poly-β-hydroxybutyrate. Here we present the whole-genome sequence of Oceanimonas sp. GK1, which consists of a single circular chromosome of 3,514,537 bp and two plasmids 8,462 and 4,245 bp in length. 相似文献
992.
Reza?Kachuei Mohammad Hossein?Yadegari?Email author Sasan?Rezaie Abdolamir?Allameh Naser?Safaie Farideh?Zaini Fatemeh?Khanezad?Yazdi 《Annals of microbiology》2009,59(2):383
Wheat is the most important cereal produced in Iran. A mycological survey was carried out for the first time, on the stored wheat samples in Tehran, East Azarbayejan and Mazandaran provinces in 2007. Exogenous and endogenous fungi, were isolated by the method of flotation with Malachite green agar (MGA 0.25) and Freeze blotter techniques respectively. In this study, 46 species belonging to 23 different genera were isolated.Cladosporium spp. (57.1–89.2%) andAlternaria spp. (82.4–100%) species were the predominant fungal species identified as endogenous mycoflora. The predominant exogenous fungi werePenicillium spp. (78.4–92.8%) andAspergillus spp. (71.4–85.7%) species.Fusarium proliferatum was the most prevalent species ofFusarium isolates.Aspergillus niger (39.4%) andAspergillus flavus (36.7%) were the predominantAspergillus species identified as exogenous mycoflora.Aspergillus flavus (26.6%) was the predominantAspergillus species identified as endogenous mycoflora. Flotation method with MGA 0.25 recommended for isolating of hyaline fungi from wheat cereals. In this study one isolate fromFusarium species was isolated on the basis of morphology and ribosomal internal transcribed spacer classified asFusarium langsethiae but on the basis of partial translation elongation factor-1alpha gene grouped withFusarium sporotrichioides. To our knowledge, this is the first report aboutF. cf.langsethiae in Iran and Asia. 相似文献
993.
Ahmadreza Mehrabian Alireza Naqinezhad Abdolrassoul Salman Mahiny Hossein Mostafavi Homan Liaghati Mohsen Kouchekzadeh 《植物学报(英文版)》2009,51(3):251-260
Add regions of the wodd occupy up to 35% of the earth's surface, the basis of various definitions of climatic conditions,vegetation types or potential for food production. Due to their high ecological value, monitoring of add regions is necessary and modem vegetation studies can help in the conservation and management of these areas. The use of remote sensing for mapping of desert vegetation is difficult due to mixing of the spectral reflectance of bright desert soils with the weak spectral response of sparse vegetation. We studied the vegetation types in the semiarid to arid region of Mond Protected Area, south-west Iran, based on unsupervised classification of the Spot XS bands and then produced updated maps.Sixteen map units covering t2 vegetation types were recognized in the area based on both field works and satellite mapping. Halocnemum strobilaceum and Suaeda fruticosa vegetation types were the dominant types and Ephedra foliata,Salicornia europaaa-Suaeda heterophylla vegetation types were the smallest. Vegetation coverage decreased sharply with the increase in salinity towards the coastal areas of the Persian Gulf. The highest vegetation coverage belonged to the riparian vegetation along the Mond River, which represents the northern boundary of the protected area. The location of vegetation types was studied on the separate soil and habitat diversity maps of the study area, which helped in final refinements of the vegetation map produced. 相似文献
994.
Adak Nasiripourdori Bijan Ranjbar Hossein Naderi-Manesh 《Theoretical biology & medical modelling》2009,6(1):3-15
Background
The details of interaction in a complex between potent antagonists such as long chain α-neurotoxins and α-conotoxins with nicotinic acetylcholine receptor (nAChR), and conformational changes induced by these antagonists, are not yet clear. 相似文献995.
Weiying Pan Chanteé M. Dancik Valery M. Nelson Zhi-Gang Jiang Michael S. Lebowitz Hossein A. Ghanbari 《Central European Journal of Biology》2009,4(1):34-40
Hydrogen peroxide (H2O2), a major non-radical reactive oxygen species (ROS) could elicit intracellular oxidative damage and/or cause extracellular
free calcium influx by activating the NMDA receptor or through calcium channels. In the present study, NMDA receptor antagonist
MK-801 fully blocked H2O2-induced neuronal cell death, whereas green tea (GT) extract containing-antioxidants only partially suppressed the neurotoxicity
of H2O2. These suggest that majority of ROS overproduction is downstream of H2O2-induced calcium influx. A novel neuroprotectant PAN-811 was previously demonstrated to efficiently attenuate ischemic neurotoxicity.
PAN-811 hereby fully blocks H2O2-elicited neuronal cell death with a more advanced neuroprotective profile than that of GT extract. PAN-811 was also shown
to protect against CaCl2-elicited neurotoxicity. Efficient protection against oxidative stress-induced neurotoxicity by PAN-811 indicates its potential
application in treatment of ROS-mediated neurodegenerative diseases.
W.P. and C.M.D. had equal contributions to this project 相似文献
996.
Ewa Kolosionek Rajkumar Savai Hossein Ardeschir Ghofrani Norbert Weissmann Andreas Guenther Friedrich Grimminger Werner Seeger Gamal Andre Banat Ralph Theo Schermuly Soni Savai Pullamsetti 《Molecular biology of the cell》2009,20(22):4751-4765
Epithelial–mesenchymal transition (EMT) has emerged as a critical event in the pathogenesis of organ fibrosis and cancer and is typically induced by the multifunctional cytokine transforming growth factor (TGF)-β1. The present study was undertaken to evaluate the potential role of phosphodiesterases (PDEs) in TGF-β1-induced EMT in the human alveolar epithelial type II cell line A549. Stimulation of A549 with TGF-β1 induced EMT by morphological alterations and by expression changes of the epithelial phenotype markers E-cadherin, cytokeratin-18, zona occludens-1, and the mesenchymal phenotype markers, collagen I, fibronectin, and α-smooth muscle actin. Interestingly, TGF-β1 stimulation caused twofold increase in total cAMP-PDE activity, contributed mostly by PDE4. Furthermore, mRNA and protein expression demonstrated up-regulation of PDE4A and PDE4D isoforms in TGF-β1-stimulated cells. Most importantly, treatment of TGF-β1 stimulated epithelial cells with the PDE4-selective inhibitor rolipram or PDE4 small interfering RNA potently inhibited EMT changes in a Smad-independent manner by decreasing reactive oxygen species, p38, and extracellular signal-regulated kinase phosphorylation. In contrast, the ectopic overexpression of PDE4A and/or PDE4D resulted in a significant loss of epithelial marker E-cadherin but did not result in changes of mesenchymal markers. In addition, Rho kinase signaling activated by TGF-β1 during EMT demonstrated to be a positive regulator of PDE4. Collectively, the findings presented herein suggest that TGF-β1 mediated up-regulation of PDE4 promotes EMT in alveolar epithelial cells. Thus, targeting PDE4 isoforms may be a novel approach to attenuate EMT-associated lung diseases such as pulmonary fibrosis and lung cancer. 相似文献
997.
Seyed Mehdi Razavi Saber Zahri Gholamreza Zarrini Hossein Nazemiyeh Sariyeh Mohammadi 《Russian Journal of Bioorganic Chemistry》2009,35(3):376-378
Cytotoxic, phytotoxic, antimicrobial and antioxidant effects of quercetin 3-O-glucoside (Q3G) isolated by HPLC from aerial parts of Prangos ferulaceae was studied by MTT assay, lettuce germination assay, disk diffusion and DPPH method. Our results showed that Q3G exhibits
high antioxidant effect with RC50 of 22 μg/mL, it has low cytotoxicity and no antibacterial effects. Q3G exhibits high phytotoxic effect with IC50 value of 282.7 μg/ml, as well. It is assumed that Q3G does not play a defense role in plants and it may act as an allelopatic
agent.
The article is published in the original. 相似文献
998.
George A. Khoury Hossein Fazelinia Jonathan W. Chin Robert J. Pantazes Patrick C. Cirino Costas D. Maranas 《Protein science : a publication of the Protein Society》2009,18(10):2125-2138
In this study we introduce a computationally‐driven enzyme redesign workflow for altering cofactor specificity from NADPH to NADH. By compiling and comparing data from previous studies involving cofactor switching mutations, we show that their effect cannot be explained as straightforward changes in volume, hydrophobicity, charge, or BLOSUM62 scores of the residues populating the cofactor binding site. Instead, we find that the use of a detailed cofactor binding energy approximation is needed to adequately capture the relative affinity towards different cofactors. The implicit solvation models Generalized Born with molecular volume integration and Generalized Born with simple switching were integrated in the iterative protein redesign and optimization (IPRO) framework to drive the redesign of Candida boidinii xylose reductase (CbXR) to function using the non‐native cofactor NADH. We identified 10 variants, out of the 8,000 possible combinations of mutations, that improve the computationally assessed binding affinity for NADH by introducing mutations in the CbXR binding pocket. Experimental testing revealed that seven out of ten possessed significant xylose reductase activity utilizing NADH, with the best experimental design (CbXR‐GGD) being 27‐fold more active on NADH. The NADPH‐dependent activity for eight out of ten predicted designs was either completely abolished or significantly diminished by at least 90%, yielding a greater than 104‐fold change in specificity to NADH (CbXR‐REG). The remaining two variants (CbXR‐RTT and CBXR‐EQR) had dual cofactor specificity for both nicotinamide cofactors. 相似文献
999.
Silvaieh H Schmid MG Hofstetter O Schurig V Gübitz G 《Journal of biochemical and biophysical methods》2002,53(1-3):1-14
The development of an enantioselective flow-through chemiluminescence immunosensor for amino acids is described. The approach is based on a competitive assay using enantioselective antibodies. Two different instrumental approaches, a flow-injection (FIA) and a sequential-injection system (SIA), are used. Compared to the flow-injection technique, the sequential injection-mode showed better repeatability. Both systems use an immunoreactor consisting of a flow cell packed with immobilized haptens. The haptens (4-amino-L- or D-phenylalanine) are immobilized onto a hydroxysuccinimide-activated polymer (Affi-prep 10) via a tyramine spacer. Stereoselective antibodies, raised against 4-amino-L- or D-phenylalanine, are labeled with an acridinium ester. Stereoselective inhibition of binding of the acridinum-labeled antibodies to the immobilized hapten by amino acids takes place. Chiral recognition was observed not only for the hapten molecule but also for a series of different amino acids. One assay cycle including regeneration takes 6:30 min in the FIA mode and 4:40 min in the SIA mode. Using D-phenylalanine as a sample, the detection limit was found to be 6.13 pmol/ml (1.01 ng/ml) for the flow-injection immunoassay (FIIA) and 1.76 pmol/ml (0.29 ng/ml ) for the sequential-injection immunoassay (SIIA) which can be lowered to 0.22 pmol/ml (0.036 ng/ml) or 0.064 pmol/ml (0.01 ng/ml) by using a stopped flow system. The intra-assay repeatability was found to be about 5% RSD and the inter-assay repeatability below 6% (within 3 days). 相似文献
1000.
Larijani B Pajouhi M Ghanaati H Bastanhagh MH Abbasvandi F Firooznia K Shirzad M Amini MR Sarai M Abbasvandi N Baradar-Jalili R 《BMC endocrine disorders》2002,2(1):3-6
BACKGROUND: Autonomous thyroid nodules can be treated by a variety of methods. We assessed the efficacy of percutaneous ethanol injection in treating autonomous thyroid nodules. METHODS: 35 patients diagnosed by technetium-99 scanning with hyperfunctioning nodules and suppressed sensitive TSH (sTSH) were given sterile ethanol injections under ultrasound guidance. 29 patients had clinical and biochemical hyperthyroidism. The other 6 had sub-clinical hyperthyroidism with suppressed sTSH levels (<0.24 &mgr;IU/ml) and normal thyroid hormone levels. Ethanol injections were performed once every 1-4 weeks. Ethanol injections were stopped when serum T3, T4 and sTSH levels had returned to normal, or else injections could no longer be performed because significant side effects. Patients were followed up at 3, 6 and, in 15 patients, 24 months after the last injection. RESULTS: Average pre-treatment nodule volume [18.2 PlusMinus; 12.7 ml] decreased to 5.7 PlusMinus; 4.6 ml at 6 months follow-up [P < 0.001]. All patients had normal thyroid hormone levels at 3 and 6 months follow-up [P < 0.001 relative to baseline]. sTSH levels increased from 0.09 PlusMinus; 0.02 &mgr;IU/ml to 0.65 PlusMinus; 0.8 &mgr;IU/ml at the end of therapy [P < 0.05]. Only 3 patients had persistent sTSH suppression at 6 months post-therapy. T4 and sTSH did not change significantly between 6 months and 2 years [P > 0.05]. Ethanol injections were well tolerated by the patients, with only 2 cases of transient dysphonia. CONCLUSION: Our findings indicate that ethanol injection is an alternative to surgery or radioactive iodine in the treatment of autonomous thyroid nodules. 相似文献