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51.
52.
Afshin Vafaei Tamer Ahmed Aline do N. Falc?o Freire Maria Victoria Zunzunegui Ricardo O. Guerra 《PloS one》2016,11(1)
Objectives
To assess the associations between gender roles and depression in older men and women and whether gender roles are independent risk factors for depression.Methods
International cross-sectional study of adults between 65 and 74 years old (n = 1,967). Depression was defined by a score of 16 or over in the Center for Epidemiologic Studies Depression Scale (CES-D). A validated 12-item Bem Sex Role Inventory (BSRI) was used to classify participants in gender roles (Masculine, Feminine, Androgynous, and Undifferentiated) using research site medians of femininity and masculinity as cut-off points. Poisson regressions were fitted to estimate the prevalence ratios (PR) of depression for each gender role compared to the masculine role, adjusting for sex, sufficiency of income, education, marital status, self-rated health, and chronic conditions.Results
Among men, 31.2% were androgynous, 26% were masculine, 14.4% were feminine, and 28.4% were undifferentiated; among women, the corresponding percentages were 32.7%, 14.9%, 27%, and 25.4%. Both in men and in women, depressive symptoms (CES-D≥16) were more prevalent in those endorsing the undifferentiated type, compared to masculine, feminine or androgynous groups. However, after adjusting for potential confounders, compared to the masculine group only those endorsing the androgynous role were 28% less likely to suffer from depression: PR of 0.72 (95% CI: 0.55–0.93). In fully adjusted models, prevalence rates of depression were not different from masculine participants in the two other gender groups of feminine and undifferentiated.Conclusions
Androgynous roles were associated with lower rates of depression in older adults, independently of being a man or a woman. 相似文献53.
Overexpression and optimization of glutamate decarboxylase in Lactobacillus plantarum Taj‐Apis362 for high gamma‐aminobutyric acid production 下载免费PDF全文
Naser Tajabadi Ali Baradaran Afshin Ebrahimpour Raha A. Rahim Fatimah A. Bakar Mohd Yazid A. Manap Abdulkarim S. Mohammed Nazamid Saari 《Microbial biotechnology》2015,8(4):623-632
Gamma‐aminobutyric acid (GABA) is an important bioactive compound biosynthesized by microorganisms through decarboxylation of glutamate by glutamate decarboxylase (GAD). In this study, a full‐length GAD gene was obtained by cloning the template deoxyribonucleic acid to pTZ57R/T vector. The open reading frame of the GAD gene showed the cloned gene was composed of 1410 nucleotides and encoded a 469 amino acids protein. To improve the GABA‐production, the GAD gene was cloned into pMG36e‐LbGAD, and then expressed in Lactobacillus plantarum Taj‐Apis362 cells. The overexpression was confirmed by SDS‐PAGE and GAD activity, showing a 53 KDa protein with the enzyme activity increased by sevenfold compared with the original GAD activity. The optimal fermentation conditions for GABA production established using response surface methodology were at glutamic acid concentration of 497.973 mM, temperature 36°C, pH 5.31 and time 60 h. Under the conditions, maximum GABA concentration obtained (11.09 mM) was comparable with the predicted value by the model at 11.23 mM. To our knowledge, this is the first report of successful cloning (clone‐back) and overexpression of the LbGAD gene from L. plantarum to L. plantarum cells. The recombinant Lactobacillus could be used as a starter culture for direct incorporation into a food system during fermentation for production of GABA‐rich products. 相似文献
54.
55.
Szegezdi E Duffy A O'Mahoney ME Logue SE Mylotte LA O'brien T Samali A 《Biochemical and biophysical research communications》2006,349(4):1406-1411
Myocardial ischemia is a severe stress condition that leads to loss of cardiomyocytes. The cell loss is attributed to apoptosis, although the exact mechanisms involved are only partially defined, which limits therapeutic opportunities. Here, we show caspase activation and apoptosis in neonatal rat cardiomyocyte cultures subjected to simulated ischemia by serum, glucose, and oxygen deprivation (SGO). Caspase activation was preceded by endoplasmic reticulum (ER) stress and the activation of the unfolded protein response (UPR), detected by the induction of Grp78, induction and splicing of XBP1, and phosphorylation of eukaryotic initiation factor 2-alpha (eIF2alpha). At a later time the ER stress response switched from UPR and cytoprotective response to a pro-apoptotic response as demonstrated by the upregulation of CHOP and processing of pro-caspase-12. Thus, we provide evidence that the ER can generate and propagate apoptotic signals in response to ischemic stress and this pathway is therefore a novel target for prevention of ischemia-mediated cardiomyocyte loss. 相似文献
56.
Julia Sandberg Patrik L. Sthl Afshin Ahmadian Magnus K. Bjursell Joakim Lundeberg 《Nucleic acids research》2009,37(8):e63
Massively parallel DNA sequencing is revolutionizing genomics research throughout the life sciences. However, the reagent costs and labor requirements in current sequencing protocols are still substantial, although improvements are continuously being made. Here, we demonstrate an effective alternative to existing sample titration protocols for the Roche/454 system using Fluorescence Activated Cell Sorting (FACS) technology to determine the optimal DNA-to-bead ratio prior to large-scale sequencing. Our method, which eliminates the need for the costly pilot sequencing of samples during titration is capable of rapidly providing accurate DNA-to-bead ratios that are not biased by the quantification and sedimentation steps included in current protocols. Moreover, we demonstrate that FACS sorting can be readily used to highly enrich fractions of beads carrying template DNA, with near total elimination of empty beads and no downstream sacrifice of DNA sequencing quality. Automated enrichment by FACS is a simple approach to obtain pure samples for bead-based sequencing systems, and offers an efficient, low-cost alternative to current enrichment protocols. 相似文献
57.
Hermatypic (reef building) corals live in an environment characterized by high ambient levels of photosynthetically active radiation (PAR) and ultraviolet radiation (UVR). Photoadaptive mechanisms have evolved to protect the sensitive cell structures of the host coral and their photosynthetic, endosymbiotic zooxanthellae. Environmental stressors may destabilize the coral-zooxanthellae system resulting in the expulsion of zooxanthellae and/or loss of photosynthetic pigment within zooxanthellae, causing a condition known as bleaching. It is estimated that 1% of the world’s coral population is lost yearly, partly due to bleaching. Despite intensive research efforts, a single unified mechanism cannot explain this phenomenon. Although UVA and UVB cellular damage is well documented, UVC damage is rarely reported due to its almost complete absorption in the stratosphere. A small scale coral propagation system at the University of Maine was accidentally exposed to 15.5 h of UVC radiation (253.7 nm) from a G15T8 germicidal lamp, resulting in a cumulative surface irradiance of 8.39 × 104 J m−2. An experiment was designed to monitor the progression of UVC induced damage. Branch sections from affected scleractinian corals, Acropora yongei and Acropora formosa were submitted to histopathology to provide an historical record of tissue response. The death of gastrodermal cells and necrosis resulted in the release of intracellular zooxanthellae into the gastrovascular canals. Zooxanthellae were also injured as evidenced by pale coloration, increased vacuolization and loss of membrane integrity. The recovery of damaged coral tissue likely proceeds by re-epithelialization and zooxanthellae repopulation of gastrodermal cells by adjacent healthy tissue. 相似文献
58.
Andrew F. Donnell Paul J. Dollings John A. Butera Arlene J. Dietrich Kerri K. Lipinski Afshin Ghavami Warren D. Hirst 《Bioorganic & medicinal chemistry letters》2010,20(7):2163-2167
Substituted pyridazino[4,5-b]indolizines were identified as potent and selective PDE4B inhibitors. We describe the structure–activity relationships generated around an HTS hit that led to a series of compounds with low nanomolar affinity for PDE4B and high selectivity over the PDE4D subtype. 相似文献
59.
The Dabska tumor also known as Endovascular papillary angioendothelioma is a rare type of hemangioendothelioma characterized by intraluminal papillary endothelial structures. Most of these are superficial in location but occurrence in deeper tissues is also known. We describe case report of testicular Dabska tumor in a child presenting as inguinal hernia. To the best of our knowledge this is the first case report describing the occurrence of this rare entity in testis. 相似文献
60.
The efficient functioning of the endoplasmic reticulum (ER) is essential for most cellular activities and survival. Conditions that interfere with ER function lead to the accumulation and aggregation of unfolded proteins. ER transmembrane receptors detect the onset of ER stress and initiate the unfolded protein response (UPR) to restore normal ER function. If the stress is prolonged, or the adaptive response fails, apoptotic cell death ensues. Many studies have focused on how this failure initiates apoptosis, as ER stress-induced apoptosis is implicated in the pathophysiology of several neurodegenerative and cardiovascular diseases. In this review, we examine the role of the molecules that are activated during the UPR in order to identify the molecular switch from the adaptive phase to apoptosis. We discuss how the activation of these molecules leads to the commitment of death and the mechanisms that are responsible for the final demise of the cell. 相似文献