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71.
Abbas Azadmehr Keyvan Alizadeh Oghyanous Reza Hajiaghaee Zahra Amirghofran Mohammad Azadbakht 《Cellular and molecular neurobiology》2013,33(8):1135-1141
In this study, the neuroprotective effect of Scrophularia striata Boiss (Scrophulariaceae) extract, a plant growing in northeastern of Iran, against oxidative stress-induced neurocytotoxicity in PC12 was evaluated. The PC12 cell line pretreated with different concentrations (10, 50, 100, and 200 μg/ml) of the extract and then treated with H2O2 to induce oxidative stress and neurotoxicity. Survival of the cells, reactive oxygen species (ROS) generation, and apoptosis were measured using MTT assay, fluorescent probe 2′,7′-dichlorofluorescein diacetate, and annexin V/propidium iodide, respectively. Moreover, the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) was used to evaluate the antioxidant capacity of the plant extract. Phytochemical assay by thin layer chromatography showed that the main components, including phenolic compounds, phenyl propanoids and flavonoids, were presented in the S. striata extract. The extract in concentrations of 50–200 μg/ml protected PC12 cells from H2O2-induced toxicity. The survival of the cells at concentration of 200 μg/ml was 64 % compared to that of H2O2 alone-treated cells (48 %) (p < 0.001). The extract also dose-dependently reduced intracellular ROS production (p < 0.001). Moreover, the extract showed antioxidative effects and decreased apoptotic cells. Collectively, these findings indicated the ability of S. striata to decrease ROS generation and cell apoptosis and also suggest the presence of the neuroprotective agents in this plant. 相似文献
72.
Padideh Ebadi Saeed Daneshmandi Abbas Ghasemi Mohammad Hossein Karimi 《Molecular biology reports》2013,40(11):6255-6260
Gallstone is a common biliary disorder with several risk factors. Immune responses and inflammatory cytokines are important in this disease; as a result, some cytokines can be detected in bile fluid. In this research, cytokine gene polymorphisms were studied, and their effects on gallstone formation were evaluated. On 158 gallstone patients and 254 normal subjects, by PCR- RFLP method, IL-4-C590T polymorphism and by ARMS-PCR method, IFN-γ T+874A, TNF-α-A308G, IL-6 G-174C and TGF-β T+869C variants were studied. Pathologic evaluations were done on surgical specimens. There were no significant differences in distribution of evaluated polymorphisms between patient group and normal control group (P > 0.05), except TGF-β +869T allele (P = 0.04, OR = 1.23, 95 % CI = 1–1.79) which was higher in patients with gallstone. Although the pro-inflammatory cytokines such as TNF-α and IL-6 may promote gallstone formation, in this study no significant correlation between TNF-α and IL-6 polymorphisms and gallstone formation was seen. It is taught that TGF-β may affect gallbladder cells to promote gallstone formation and higher producer TGF-β +869T allele can be a risk factor of gallstone disease, so further studies would be more elucidative. 相似文献
73.
Seyed Mahmoud Hashemi Zuhair Mohammad Hassan Ali Akbar Pourfathollah Sara Soudi Abbas Shafiee Masoud Soleimani 《Journal of cellular biochemistry》2013,114(4):955-965
Adipose tissue‐derived mesenchymal stem cells (AD‐MSCs) have been shown to be capable of differentiating into multiple cell type and exert immunomodulatory effects. Since the selection of ideal stem cell is apparently crucial for the outcome of experimental stem cell therapies, therefore, in this study we compared AD‐MSCs conditioned media (CM) from BALB/c, C57BL/6, and DBA mouse strains. No significant difference was found in the morphology, cell surface markers, in vitro differentiation and proliferation potentials of AD‐MSCs isolated from C57BL/6, BALB/c, and DBA mice. The immunological assays showed some variation among the strains in the cytokines, nitric oxide (NO), and indoleamine 2,3‐dioxygenase (IDO) production and immunomodulatory effects on splenocytes functions. Our results indicated a suppression of splenocytes proliferation in the presence of AD‐MSC CM from the three inbred mouse strains. However, BALB/c CM exerted a higher suppression of splenocytes proliferation. AD‐MSCs isolated from C57BL/6 and BALB/c mice produced higher levels of TGF‐β than those from DBA mice. Furthermore, IL‐17 and IDO production was higher in AD‐MSCs isolated from BALB/c mice. Our results indicated an increased production of TGF‐β, IL‐4, IL‐10, NO, and IDO by splenocytes in response to CM from BALB/c AD‐MSCs. In conclusion, our results showed that the immunomodulatory properties of mouse AD‐MSCs is strain‐dependent and this variation should be considered during selection of appropriate stem cell source for in vivo experiments and stem cell therapy strategies. J. Cell. Biochem. 114: 955–965, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
74.
A body fossil of the starfish Metopaster parkinsoni was collected from chalky rocks of the Coniacian – Santonian transition in the Abderaz Formation at the Padeha section, east of Mashhad (Kopet-Dagh, Iran). The species is common in the English Chalk and is well known from the Cenomanian to the Maastrichtian of Europe. The new Iranian occurrence of M. parkinsoni extends its geographical range of 700 km to the South and 2500 km to the East. The species proliferated in upper offshore environments of the North Tethyan continental shelves. The outstanding occurrence of many well-preserved specimens during the Coniacian – Santonian transition in Europe and Iran may be related to favorable taphonomic conditions driven by the Ocean Anoxic Event (OAE III). 相似文献
75.
Muhammad Saqib Javaid Akhtar Ghulam Abbas Muhammad Nasim 《Acta Physiologiae Plantarum》2013,35(9):2761-2768
Salinity and drought are important agro-environmental problems occurring separately as well as together with the combined occurrence increasing with time due to climate change. Screening of bread wheat genotypes against salinity or drought alone is common; however, little information is available on the response of wheat genotypes to a combination of these stresses. This study investigates the response of a salt-resistant (SARC-1) and a salt-sensitive (7-Cerros) wheat genotype to drought at different growth stages under non-saline (ECe 2.1 dS m?1) and saline soil (ECe 15 dS m?1) conditions. Drought was applied by withholding water for 21 days at a particular growth stage viz. tillering, booting, and grain filling stages. At booting stage measurements regarding water relations, leaf ionic composition and photosynthetic attributes were made. At maturity grain yield and different yield, components were recorded. Salinity and drought significantly decreased grain yield and different yield components with a higher decrease in the case of combined stress of salinity × drought. The complete drought treatment (drought at tillering + booting + grain filling stages) was most harmful for wheat followed by drought at booting stage and grain filling–tillering stages, respectively. The salt-resistant wheat genotype SARC-1 performed better than the salt-sensitive genotype 7-Cerros in different stress treatments. A decrease in the water and turgor potentials, photosynthetic and transpiration rates, stomatal conductance, leaf K+, and increased leaf Na+ were the apparent causes of growth and yield reduction of bread wheat due to salinity, drought, and salinity × drought. 相似文献
76.
Ali Sonboli Nayyereh Olanj Valiollah Mozaffarian Abbas Gholipour 《Nordic Journal of Botany》2013,31(5):590-594
Ajania semnanensis (Compositae: Anthemideae), a new species of Ajania from northeast of Iran, Semnan province, is described and illustrated. Ajania semnanensis is a suffruticose perennial growing on rocky and stony slopes of mountains at altitudes of 1500–2800 m a.s.l. Karyological and micromorphological data of the pollen and achenes, as well as a distribution map for the species are provided. The cytotype of the species was found to be diploid (2n = 2x = 18) based on x = 9. The karyotype formula is 2n = 2x = 4M + 6m + 6sm + 2st. Pollen grains of A. semnanensis are prolate‐spheroidal (P/E = 1.1), 3‐zonocolporate and echinate (Anthemis type). The achenes of A. semnanensis are obovate, 1.0–1.5 × 0.5–0.6 mm, light brown, with 4–6 fine and inconspicuous ribs, glabrous, without pappus and with a subbasal carpopodium. The IUCN status of the new species is suggested to be ‘Least Concern’ (LC). 相似文献
77.
Yaghoub Yazdani Neda Keyhanvar Hamid Reza Kalhor Abbas Rezaei 《Biotechnology letters》2013,35(8):1191-1197
Hepcidin is a peptide hormone that plays an important role in iron metabolism. We have produced a recombinant mouse hepcidin-1 by using baculovirus expression system. Its expression yield was 25 μg/ml when cell culture media were supplemented with a protease inhibitor cocktail. The recombinant mouse hepcidin-1 and synthetic human hepcidin-25 had similar effects on reducing ferroportin expression in J774A cell line and in peritoneal macrophages. However, synthetic human hepcidin-25 was more efficient than recombinant mouse hepcidin-1 in reducing iron concentration in blood circulation (p < 0.01). 相似文献
78.
79.
Vishal M. Gohil Lin Zhu Charli D. Baker Valentin Cracan Abbas Yaseen Mohit Jain Clary B. Clish Paul S. Brookes Marica Bakovic Vamsi K. Mootha 《The Journal of biological chemistry》2013,288(49):35387-35395
We recently identified meclizine, an over-the-counter drug, as an inhibitor of mitochondrial respiration. Curiously, meclizine blunted respiration in intact cells but not in isolated mitochondria, suggesting an unorthodox mechanism. Using a metabolic profiling approach, we now show that treatment with meclizine leads to a sharp elevation of cellular phosphoethanolamine, an intermediate in the ethanolamine branch of the Kennedy pathway of phosphatidylethanolamine biosynthesis. Metabolic labeling and in vitro enzyme assays confirmed direct inhibition of the cytosolic enzyme CTP:phosphoethanolamine cytidylyltransferase (PCYT2). Inhibition of PCYT2 by meclizine led to rapid accumulation of its substrate, phosphoethanolamine, which is itself an inhibitor of mitochondrial respiration. Our work identifies the first pharmacologic inhibitor of the Kennedy pathway, demonstrates that its biosynthetic intermediate is an endogenous inhibitor of respiration, and provides key mechanistic insights that may facilitate repurposing meclizine for disorders of energy metabolism. 相似文献
80.
Amir Assadieskandar Amirali Amirhamzeh Marjan Salehi Keriman Ozadali Seyed Nasser Ostad Abbas Shafiee Mohsen Amini 《Bioorganic & medicinal chemistry》2013,21(8):2355-2362
A series of 4-aryl-5-(4-(methylsulfonyl)phenyl)-2-alkylthio and 2-alkylsulfonyl-1H-imidazole derivatives were synthesized. All compounds were tested in human blood assay to determine COX-1 and COX-2 inhibitory potency and selectivity. Among the synthesized compounds, 2-alkylthio series were more potent and selective than 2-sulfonylalkyl derivatives. In molecular modeling, interaction of 2-sulfonylalkyl moiety with Arg120 in COX-1 and an extra hydrogen bond with Tyr341 in COX-2 increased the residence time of ligands in the active site in 2-sulfonylalkyl and 2-alkylthio analogs, respectively. 相似文献