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1.
Major histocompatibility complex (Mhc) genes are frequently used as a model for adaptive genetic diversity. Although associations between Mhc and disease resistance are frequently documented, little is known about the fitness consequences of Mhc variation in wild populations. Further, most work to date has involved testing associations between Mhc genotypes and fitness components. However, the functional diversity of the Mhc, and hence the mechanism by which selection on Mhc acts, depends on how genotypes map to the functional properties of Mhc molecules. Here, we test three hypotheses that relate Mhc diversity to fitness: (i) the maximal diversity hypothesis, (ii) the optimal diversity hypothesis and (iii) effect of specific Mhc types. We combine mark–recapture methods with analysis of long‐term breeding data to investigate the effects of Mhc class I functional diversity (Mhc supertypes) on individual fitness in a wild great tit (Parus major) population. We found that the presence of three different Mhc supertypes was associated with three different components of individual fitness: survival, annual recruitment and lifetime reproductive success (LRS). Great tits possessing Mhc supertype 3 experienced higher survival rates than those that did not, whereas individuals with Mhc supertype 6 experienced higher LRS and were more likely to recruit offspring each year. Conversely, great tits that possessed Mhc supertype 5 had reduced LRS. We found no evidence for a selective advantage of Mhc diversity, in terms of either maximal or optimal supertype diversity. Our results support the suggestion that specific Mhc types are an important determinant of individual fitness.  相似文献   
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Transfusion-transmitted virus (TTV) is a recently discovered transfusion-transmissible DNA virus. Its frequency and clinical impact has not been established in cancer patients in Turkey. In this study, we determined the prevalence of TTV DNA positivity, and its relationship with history of transfusion, amount of transfusion, age and sex in patients with hematological and solid malignancies. Sixty-one patients (35 male and 26 female) followed up for various malignancies and 45 healthy subjects were included in the study. ITV DNA was assayed by the polymerase chain reaction (PCR). TTV DNA was detected in 18 of 61 patients (29.5%) and in 5 of 45 control subjects (11.1%). In cancer patients, the prevalence of TTV DNA positivity was higher to comparison with control group. In addition, the prevalence of TTV DNA positivity was significantly higher in 22 patients who had a history of blood transfusion in the last 6 months than 39 patients who had no current or past history of transfusion (40.9% vs 23.0% respectively). These results suggest that the prevalence of TTV DNA is high and the parenteral route is an important mode of transmission for TTV in cancer patients. In addition, the high prevalence and persistence of TTV in cancer patients with parenteral risk exposure could be related to the immunodeficiency due to cancer and high viral loads by parenteral route.  相似文献   
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The functional role of IGFBP5 in breast cancer is complicated. Experimental and bioinformatics studies have shown that IGFBP5 is targeted by miR-140-5p and miR-193b, although this has not yet been proven in clinical samples. The aim of this study was to evaluate the expression of miR-140-5p and miR-193b in breast cancer and adjacent normal tissue and assess its correlation with IGFBP5 and the clinicopathological characteristics of the tumors. IGFBP5 protein expression was analyzed immunohistochemically and IGFBP5, miR-140 and miR-193b mRNA expression levels were analyzed with real-time RT-PCR. Tumor tissue had higher miR-140-5p expression than adjacent normal tissue (p = 0.015). Samples with no immunohistochemical staining for IGFBP5 showed increased miR-140-5p expression (p = 0.009). miR-140-5p expression was elevated in invasive ductal carcinomas (p = 0.002), whereas basal-like tumors had decreased expression of miR-140-5p compared to other tumors (p = 0.008). Lymph node-positive samples showed an approximately 13-fold increase in miR-140-5p expression compared to lymph node-negative tissue (p = 0.049). These findings suggest that miR-140-5p, but not miR-193b, could be an important determinant of IGFBP5 expression and clinical phenotype in breast cancer patients. Further studies are needed to clarify the expressional regulation of IGFBP5 by miR-140-5p.  相似文献   
4.
The major functional alpha1-adrenoceptor in the rat aorta is of the alpha1Dsubtype and that in the caudal artery is of the alpha1A subtype. In the present study, the participation of protein kinase C (PKC) and Rho kinase (RhoK) in contractile responses to stimulation of the alpha1-adrenoceptors in these two arteries was investigated. Both the PKC inhibitor Ro-318220 and the RhoK inhibitor Y-27632 significantly blocked contractile responses of the aorta to phenylephrine (PE) and the selective alpha1A-adrenoceptor agonist A61603. When used in combination, the inhibitors had an additive blocking effect. In the caudal artery, Y-27632 but not Ro-318220 inhibited contractile responses to PE and A61603, and, in combination, the antagonism produced was no greater than that by Y-27632 alone. Contractile responses to direct activation of PKC with phorbol 12,13-dibutyrate were much smaller and levels of CPI-17 (PKC-activated protein phosphatase inhibitor of 17 kDa) were much lower in the caudal artery than the aorta. The results suggest that both PKC and RhoK contribute independently to contractile responses to stimulation of alpha1D-adrenoceptors in the aorta. However, RhoK, but not PKC, participates in contractile responses to stimulation of alpha1A-adrenoceptors in the caudal artery. This difference may largely be due to differences between the two arteries in the extent to which PKC participates in contraction.  相似文献   
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Automated cell imaging systems facilitate fast and reliable analysis of biological events at the cellular level. In these systems, the first step is usually cell segmentation that greatly affects the success of the subsequent system steps. On the other hand, similar to other image segmentation problems, cell segmentation is an ill-posed problem that typically necessitates the use of domain-specific knowledge to obtain successful segmentations even by human subjects. The approaches that can incorporate this knowledge into their segmentation algorithms have potential to greatly improve segmentation results. In this work, we propose a new approach for the effective segmentation of live cells from phase contrast microscopy. This approach introduces a new set of “smart markers” for a marker-controlled watershed algorithm, for which the identification of its markers is critical. The proposed approach relies on using domain-specific knowledge, in the form of visual characteristics of the cells, to define the markers. We evaluate our approach on a total of 1,954 cells. The experimental results demonstrate that this approach, which uses the proposed definition of smart markers, is quite effective in identifying better markers compared to its counterparts. This will, in turn, be effective in improving the segmentation performance of a marker-controlled watershed algorithm.  相似文献   
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There is a growing body of evidence about metformin being effective in cancer therapy. Despite controversies about the ways of its effectiveness, several ongoing clinical trials are evaluating the drug when used as an adjuvant or a neo-adjuvant agent. We aimed to investigate metformin’s effects on proliferation, metastasis, and hormone receptor expressions in breast cancer cell line MCF-7 incubated in two different glucose conditions. MCF-7 cells were incubated in high or low glucose media and treated with various doses of metformin. The cell viability was studied using MTT test. The Ki-67, estrogen and progesterone receptor expression were evaluated by ICC and galectin-3 expression was evaluated by ELISA or spectrophotometrically. The cell viability following consecutive metformin doses in either glucose condition for 24 and 48 h represented a significant decrease when compared to control. The proliferation detected in low glucose medium following metformin at doses < 20 mM was found significantly decreased when compared to high glucose medium at 48 h. In terms of galectin-3 levels, the increase in high glucose medium treated with metformin and the decrease in low glucose medium were found statistically significant when compared to control. Progesterone receptor staining demonstrated a significant increase in low glucose medium. Our findings represent better outcomes for cancer lines incubated in low glucose medium treated with metformin in terms of viability, receptor expression and metastatic activity, and highlight the potential benefit of metformin especially in restraining the cancer cell’s ability to cope energetic stress in low glucose conditions.  相似文献   
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The genus Verbascum (mulleins), belonging to the family Scrophulariaceae, comprises about 360 species of flowering plants. The leaves, flowers and whole aerial parts of Verbascum spp. have been widely used in traditional medicine for the treatment of respiratory and inflammatory disorders and also display powerful wound healing activity. Verbascum species are found to accumulate several groups of bioactive molecules, therefore they might be utilized as attractive sources of new (drug) leads. The present review attempts to provide an up-to-date comprehensive overview on phytochemical and pharmacological aspects of Verbacum spp. research along with some successful examples of growing (and transforming) mulleins in vitro.  相似文献   
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