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91.
Flodgren E Olde B Meidute-Abaraviciene S Winzell MS Ahrén B Salehi A 《Biochemical and biophysical research communications》2007,354(1):240-245
The free fatty acid receptor, GPR40, has been coupled with insulin secretion via its expression in pancreatic beta-cells. However, the role of GPR40 in the release of glucagon has not been studied and previous attempts to identify the receptor in alpha-cells have been unfruitful. Using double-staining for glucagon and GPR40 expression, we demonstrate that the two are expressed in the same cells in the periphery of mouse islets. In-R1-G9 hamster glucagonoma cells respond dose-dependently to linoleic acid stimulation by elevated phosphatidyl inositol hydrolysis and glucagon release and the cells become increasingly responsive to fatty acid stimulation when overexpressing GPR40. Isolated mouse islets also secrete glucagon in response to linoleic acid, a response that was abolished by antisense treatment against GPR40. This study demonstrates that GPR40 is present and active in pancreatic alpha-cells and puts further emphasis on the importance of this nutrient sensing receptor in islet function. 相似文献
92.
The efficiency of Trichoderma harzianum (MIAU 145 C) in promoting kidney bean (cv. Goli) growth in different soil texture (sandy loam, loam and clay loam) and organic matter content (0.5 and 2% of leaf litter) was assessed in a factorial experiment in the absence of Meloidogyne javanica. In another factorial experiment, the effect of soil texture, soil organic content and control measure (no control, 10?ml of T. harzianum containing 106 spore ml?1 and 2?mg ai cadusafos kg?1 soil) was determined on nematode-infected kidney bean’s growth, fungus controlling activity and M. javanica reproduction. Except for the shoot length, the fungus improved plant growth. Clay loam was not a proper soil type for the cultivation of kidney bean plants (even in the soil without nematode), but the plant grew better in sandy loam and loam soil. The presence of leaf litter in the soil enhanced plant growth, increased fungal efficiency and increased nematode reproduction. It seems that T. harzianum can activate the plant defence system in sandy loam soil. T. harzianum was more effective in sandy loam or loam soil containing 2% organic matter (leaf litter) and reduced the reproduction factor of the nematode in the tested soil textures equally to the chemical nematicide treatment. 相似文献
93.
M. Salehi S. A. Esmailzadeh Hosseini E. Salehi A. Bertaccini 《Folia microbiologica》2017,62(2):99-109
During 2010–14 surveys in the major sesame growing areas of Fars, Yazd and Isfahan provinces (Iran), genetic diversity and vector transmission of phytoplasmas associated with sesame phyllody were studied. Virtual RFLP, phylogenetic, and DNA homology analyses of partial 16S ribosomal sequences of phytoplasma strains associated with symptomatic plants revealed the presence of phytoplasmas referable to three ribosomal subgroups, 16SrII-D, 16SrVI-A, and 16SrIX-C. The same analyses using 16S rDNA sequences from sesame phyllody-associated phytoplasmas retrieved from GenBank database showed the presence of phytoplasmas clustering with strains in the same subgroups in other Iranian provinces including Bushehr and Khorasan Razavi. Circulifer haematoceps and Orosius albicinctus, known vectors of the disease in Iran, were tested for transmission of the strains identified in this study. C. haematoceps transmitted 16SrII-D, 16SrVI-A, and 16SrIX-C phytoplasmas, while O. albicinctus only transmitted 16SrII-D strains. Based on the results of the present study and considering the reported presence of phytoplasmas belonging to the same ribosomal subgroups in other crops, sesame fields probably play an important role in the epidemiology of other diseases associated with these phytoplasmas in Iran. 相似文献
94.
Zahra Kabiri Mansoor Salehi Fariborz Mokarian Farzaneh Mahmoodi Iman Doostan Mohammad Reza Ataollahi 《Cellular immunology》2009,259(2):111-116
The participation of Abl-Related Gene (ARG) is demonstrated in pathogenesis of different human malignancies. However there is no conclusive evidence on ARG expression level in mature B cell lymphomas. In this study we evaluated ARG protein expression in Follicular Lymphoma (FL), Burkitt’s Lymphoma (BL) and Diffused Large B Cell Lymphoma (DLBCL) in comparison with non-neoplastic lymph nodes. Semi-quantitative fluorescent ImmunoHistoChemistry was applied on 14, 7 and 4 patients with DLBCL, FL and BL respectively, adding to 4 normal and 4 reactive lymph nodes. The mean ratio of ARG/GAPDH expression was significantly different (p < 0.00) between lymphomas and control samples, with DLBCL having the highest ARG expression amongst all. Over expression of ARG was seen in FL and BL, with FL expressing statistically more ARG than BL. Moreover, the ARG/GAPDH expression ratio increased from DLBCL stage I towards stage VI, all showing significantly more ARG expression than FL and BL (in all cases p < 0.00). 相似文献
95.
Sameni S Ghayumi MA Mortazavi G Faghih Z Kashef MA Ghaderi A 《Molecular biology reports》2009,36(5):1001-1005
Lung cancer is one of the leading causes of death from cancer. Both immune cells and tumor cells play a key role in lung cancer
immunity by secretion of cytokines and developing type-2 cell-mediated immune response. IL-13 is an immunoregulatory cytokine
affecting tumor immunosurveillance by deviation of immune response from Th1 to Th2. In the present study we sought to determine
the association of single nucleotide polymorphisms (SNPs) of IL-13 gene at positions +2044 (G/A) and −1055 (C/T) and lung cancer. One hundred forty one patients and 113 controls were recruited;
control group was subdivided into smoker and nonsmoker individuals for serum detection. Genotyping was carried out by PCR-RFLP
assay and IL-13 detection by ELISA method. No statistically significant difference was found in the frequency of genotypes,
alleles, and haplotypes at positions +2044 (G/A) and −1055 (C/T) of IL-13 gene between lung cancer patients and controls. Serum level of IL-13 was not detectable in both groups. The results of this
study reveal that although +2044 (G/A) and −1055 (C/T) SNPs in IL-13 are implicated in some pulmonary processes, they do not confer susceptibility to lung cancer in Iranian population. 相似文献
96.
Soltani F Mosaffa F Iranshahi M Karimi G Malekaneh M Haghighi F Behravan J 《Cell biology and toxicology》2009,25(3):291-296
The protective properties of a prenylated coumarin, umbelliprenin (UMB), on the human lymphocytes DNA lesions were tested.
Lymphocytes were isolated from blood samples taken from healthy volunteers. DNA breaks and resistance to H2O2-induced damage were measured using a single-cell microgel electrophoresis technique under alkaline conditions (comet assay).
Human lymphocytes were incubated in UMB (10, 25, 50, 100, 200, and 400 μM) alone or a combination of different concentrations
of UMB (10, 25, 50, 100, 200, and 400 μM) and 25 μM H2O2. Untreated cells, ascorbic acid (AA; 25, 50, 100, 200, and 400 μM) and H2O2 (25 μM) were considered as negative control, positive control, and the standard antioxidant agent for our study, respectively.
Single cells were analyzed with “TriTek Cometscore version 1.5” software. The DNA damage was expressed as percent tail DNA.
UMB exhibited a concentration-dependent increase in protection activity against DNA damage induced by 25 μM H2O2 (from 67.28% to 39.17%). The antigenotoxic activity of AA, in the range 0–50 μM, was greater than that of UMB. However, no
significant difference (p > 0.05) in the protective activity was found between UMB and AA at concentrations of approximately higher than 50 μM. 相似文献
97.
Parvin Salehi Shanjani Mohsen Mardi Leila Pazouki Marianna Hagidimitriou Damiano Avanzato S. Mostafa Pirseyedi Mohammad Reza Ghaffari S. Mojtaba Khayam Nekoui 《Tree Genetics & Genomes》2009,5(3):447-458
Knowledge of pistachio genetic diversity is necessary for the formulation of appropriate management strategies for the conservation
of these species. We analysed amplified fragment length polymorphisms in a total of 216 pistachio accessions, which included
seven populations from three wild species (Pistacia vera, Pistacia khinjuk and Pistacia atlantica subsp. kurdica) and most of the important cultivars from Iran, together with some foreign cultivars. High levels of genetic diversity were
detected within the Iranian cultivars, and they showed a clear separation from foreign cultivars, as revealed by unweighted
pair group method with arithmetic averaging and supported by analysis of molecular variance. The lowest amount of polymorphism
was observed in P. atlantica subsp. kurdica, which showed the lowest number of total bands as compared to the other species. This revealed strong genetic erosion of
P. atlantica subsp. kurdica, which reflected a severe decline in habitat and over-exploitation. Based on these findings, strategies are proposed for
the genetic conservation and management of pistachio species and cultivars. 相似文献
98.
Mojtaba Tabatabaei Yazdi Gholamreza Zarrini Elham Mohit Mohammad Ali Faramarzi Neda Setayesh Navid Sedighi Farzaneh Aziz Mohseni 《World journal of microbiology & biotechnology》2006,22(4):325-330
Summary One hundred and sixty-five strains of microorganisms with the ability to grow in a medium containing uric acid as a major
source of nitrogen were isolated from soil samples during a screening program. Among them, a zygomycete fungus with well-developed
columellae was recognized to produce high levels of the enzyme in a short time. Classification of the isolated fungus was
carried out according to the morphological and culture characteristics of the organism, and it was identified as Mucor hiemalis. The fungus was able to produce an intracellular urate oxidase in a fermentation medium mainly containing uric acid. Optimized
composition of the medium consisted of (l−1 of distilled water) uric acid, 7.0 g; maltose, 6.0 g; Vogel stock solution, 20 and 1 ml of 0.5 M copper sulphate. The optimum
pH and temperature for uricase production in the optimized medium were pH 6 and 30 °C, respectively. 相似文献
99.
100.
Tarlan Eslami-Arshaghi Saeid Vakilian Ehsan Seyedjafari Abdolreza Ardeshirylajimi Masoud Soleimani Mohammad Salehi 《In vitro cellular & developmental biology. Animal》2017,53(4):371-380
A combination of nanotopographical cues and surface modification of collagen and fibronectin is a potential platform in primordial germ cells (PGCs) differentiation. In the present study, the synergistic effect of nanotopography and surface modification on differentiation of nuclear transfer embryonic stem cells (nt-ESCs) toward PGC lineage was investigated. In order to achieve this goal, poly-anyline (PANi) was mix within poly-l-lactic acid (PLLA). Afterward, the random composite mats were fabricated using PLLA and PANi mix solution. The nanofiber topography notably upregulated the expressions of prdm14, mvh and c-kit compared with tissue culture polystyrene (TCP). Moreover, the combination of nanofiber topography and surface modification resulted in more enhancement of PGCs differentiation compared with non-modified nanofibrous scaffold. Additionally, gene expression results showed that mvh and c-kit were expressed at higher intensity in cells exposed to collagen and fibronectin rather than collagen or fibronectin solitary. These results demonstrated the importance of combined effect of collagen and fibronectin in order to develop a functional extracellular matrix (ECM) mimic in directing stem cell fate and the potential of such biofunctional scaffolds for treatment of infertility. 相似文献