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181.
Maedi-Visna is an important slow viral disease of sheep leading to progressive pneumonia, encephalitis and mastitis. Udder is one of the organs affected by MVV. Despite the fact that in Iran Maedi-Visna is known since 2000, to the authors’ knowledge correlation of subclinical mastitis and infection with MVV has not been assayed. In this study 50 milk samples from 10 flocks in East Azerbaijan Province of Iran were tested. None of the animals exhibited any clinical signs of the disease. Forty samples were collected from CMT positive ewes and ten were taken from CMT negative ewes. Milk samples were analyzed using PCR targeting gag sequence. Presence of provirus DNA was detected in one sample from CMT negative and seven samples from CMT positive ewes. These data demonstrate that 16.5 % of sheep with subclinical mastitis were infected to MVV. Thus this virus can be considered one of the main pathogenic agents of mastitis and can be dramatically transmitted to lambs by milk.  相似文献   
182.
Valerenic acid (VA) is a pharmacologically-active sesquiterpene found in valerian (Valeriana officinalis L., Valerianaceae) roots and rhizomes. The plant produces only small amounts of this metabolite naturally. So, induction of hairy roots as well as elicitation can be useful to increase its commercial production. In this study, Wild-type strain ‘A13’ of Agrobacterium rhizogenes was used to induce hairy roots in valerian. The influence of three different elicitors including Fusarium graminearum extract (FE), methyl jasmonate (MJ) and salicylic acid (SA) on VA production in the selected hairy root line ‘LeVa-C4’ was also investigated. The 23-day-old cultures were treated with different concentrations of the elicitors at exposure time of 3 and 7 days. FE (1%) and MJ (100 µM L?1) highly promoted VA production at 7 days after elicitation, to a level of 12.31- and 6-fold higher than that of non-elicited controls, respectively, and FE did not exert any negative effects on biomass yield of hairy root. SA did not significantly increase the production of VA. This is the first time study to assess the elicitation of hairy root cultures to promote VA biosynthesis in valerian and the resulting experiments demonstrated that F. graminearum extract and MJ were indeed a potent inducer of VA biosynthesis.  相似文献   
183.
Five species (14 ecotypes) belonging to three subgenera of ornamental-medicinal Iranian Fritillaria plant were chromosomally and karyotypically assessed, using squash technique and 1 % (w/v) aceto-orcein stain. All species were diploid (2n = 2x = 24) having mean chromosome length of 16.8 μm (14.2–18.6 μm). The satellites varied in number (1–4 pairs) and in size (1.27–3.01 μm): mostly locating on long arms. Four chromosome types (“m”, “sm”, “st”, “T”) formed 11 different karyotypic formulas: the latter is being reported for the first time in some ecotypes in either S1 or S4. Nine chromosomal parameters were calculated. ANOVA verified intra- and inter-specific chromosomal variation in examined Iranian Fritillaria species. Twelve different methods were used to assess the degree of karyotype asymmetry. Among those, one qualitative (Stebbins classification) and seven quantitative (TF %, CVTL, DI, AsK %, A2, Rec, CG %) parameters verified that S2 and S5 species were recognized as having the most asymmetrical and symmetrical karyotypes, respectively.  相似文献   
184.
The goal of this study was to evaluate the protective and mitigative effect of vitamin C on oxidative stress in differentiated thyroid cancer (DTC) patients ablated with radioiodine. 58 DTC patients selected for radioactive iodine therapy (RAIT) with 5550 MBq 131Iodine were divided into four groups. Group 1 (control group) consisted of patients who underwent RAIT routinely. Other patients received 1500 mg vitamin C daily 2 days after (group 2), 2 days before to 2 days after (group 3) and 2 days before RAIT (group 4). Serum oxidative stress markers including malondialdehyde (MDA), glutathione (GSH), catalase (CAT), and superoxide dismutase (SOD) were measured immediately before and 2 days after RAIT. A significant increase in MDA after RAIT was observed in all groups (p?<?0.05). The concentrations of MDA were significantly higher in the control group compared to the intervention groups (p?<?0.05). A significant decrease in the control group (p?<?0.05) and increase in group 4 (p?<?0.05) were observed in GSH level after RAIT (p?<?0.05). Mean variation of GSH was significant between control group with groups 3 (p?<?0.01) and 4 (p?<?0.01). The results indicate that activity of SOD remained unchanged in all groups (p?>?0.05). A significant increase was observed in CAT activity after RAIT in all groups (p?<?0.05), which was higher in control group than intervention groups. In groups 3 (p?<?0.05) and 4 (p?<?0.05), this increase in CAT activity was significantly lower than the control group. RAIT causes serum oxidative stress, which can be ameliorated using vitamin C as an antioxidant. These results indicate that radioprotective effect of vitamin C is preferable to its mitigative effect.  相似文献   
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Since, proteins carry out many functional roles in a cell with different concentrations, proteomics is likely a more appropriate approach to explain biological processes and cellular events than mRNA studies. Although, gene ontology provides a systematic and organized vocabulary of biological terms for proteins, we need more details to decide about the correct duty and annotation of proteins in a specific condition. One can assume that a change of protein concentration is related to a biological process of that protein with negligible error. Therefore, we can obtain more information about the function of proteins by studying these profiles. In this study, we used time-course proteomic data of a twenty day differentiation study of embryonic stem cells (ESCs) differentiating to embryoid bodies (EBs). Hierarchical clustering was used to cluster time-series concentration profile of proteins. Our results demonstrate that there are eleven active processes with distinct concentration profiles in this initial differentiation. According to the concentration profiles of proteins, we suggest new change points (or equivalently, new stages) in the course of embryonic differentiation.  相似文献   
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189.
A variety of epigenetic factors involved in leukemia pathogenesis. Among various epigenetic factors, microRNAs (miRNAs) have emerged as important players, which affect a sequence of cellular and molecular signaling pathways. Leukemia is known as progressive cancer, which is related to many health problems in the world. It has been shown that the destruction of the blood-forming organs could lead to abnormal effects on the proliferation and development of leukocytes and their precursors. Despite many attempts for approved effective and powerful therapies for patients with leukemia, finding and developing new therapeutic approaches are required. One of the important aspects of leukemia therapy, identification of underlying cellular and molecular mechanisms involved in the pathogenesis of leukemia. Several miRNAs (ie, miR-103, miR-101, mit-7, let-7i, miR-424, miR-27a, and miR-29c) and play major roles in response to therapy in patients with leukemia. miRNAs exert their effects by targeting a variety of targets, which are associated with response to therapy in patients with leukemia. It seems that more understanding about the roles of miRNAs in response to therapy in patients with leukemia could contribute to better treatment of patients with leukemia. Here, for the first time, we summarized various miRNAs, which are involved in response to therapy in the treatment patients with leukemia.  相似文献   
190.
ABSTRACT: BACKGROUND: It was reported that antiretroviral drugs such as efavirenz can increase the catabolism of vitamin D in HIV infected individuals. We have not found any study that evaluated effects of vitamin D supplementation on the bone specific biomarkers in HIV positive patients under treatment with antiretroviral regimen containing efavirenz. FINDINGS: Vitamin D deficiency was detected in 88.4 % of included patients. Baseline osteocalcin, but not collagen telopeptidase, serum levels were lower than normal range in all of these individuals. Both bone biomarkers' concentrations increased significantly (p < 0.001 for both of them) after supplementation of vitamin D and it was more predominant for osteocalcin. CONCLUSION: In the HIV-infected patients under treatment with efavirenz, vitamin D deficiency is prevalent. After supplementation with single dose of 300,000 IU vitamin D in this population, the activation of osteoblasts and osteoclasts stimulates bone formation and resorption respectively with favorable bone formation without any adverse event. Significant percent of HIV infected individuals are vitamin d deficient that could benefit from vitamin D supplementation.  相似文献   
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