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1.
Epigenetic histone trimethylation on lysine 9 (H3K9me3) represents a major molecular signal for genome stability and gene silencing conserved from worms to man. However, the functional role of the H3K9 trimethylases SUV39H1/2 in mammalian tissue homeostasis remains largely unknown. Here, we use a spontaneous dog model with monogenic inheritance of a recessive SUV39H2 loss-of-function variant and impaired differentiation in the epidermis, a self-renewing tissue fueled by stem and progenitor cell proliferation and differentiation. Our results demonstrate that SUV39H2 maintains the stem and progenitor cell pool by restricting fate conversion through H3K9me3 repressive marks on gene promoters encoding components of the Wnt/p63/adhesion axis. When SUV39H2 function is lost, repression is relieved, and enhanced Wnt activity causes progenitor cells to prematurely exit the cell cycle, a process mimicked by pharmacological Wnt activation in primary canine, human, and mouse keratinocytes. As a consequence, the stem cell growth potential of cultured SUV39H2-deficient canine keratinocytes is exhausted while epidermal differentiation and genome stability are compromised. Collectively, our data identify SUV39H2 and potentially also SUV39H1 as major gatekeepers in the delicate balance of progenitor fate conversion through H3K9me3 rate-limiting road blocks in basal layer keratinocytes.  相似文献   
2.
Molecular Biology Reports - In this study we used two different techniques in order to isolate pericytes from the wall of human umbilical cord vein and get two different groups of cells were named...  相似文献   
3.
Bisphenol A (BPA) is an endocrine disruptor chemical, which is commonly used in everyday products. Adverse effects of its exposure are reported even at picomolar doses. Effects of picomolar and nanomolar concentrations of BPA on cytotoxicity, nitric oxide (NO) levels, acetylcholinesterase (AChE) gene expression and activity, and tumor necrosis factor‐α (TNF‐α) and caspase‐8 levels were determined in SH‐SY5Y cells. The current study reveals that low‐dose BPA treatment induced cytotoxicity, NO, and caspase‐8 levels in SH‐SY5Y cells. We also evaluated the mechanism underlying BPA‐induced cell death. Ours is the first report that receptor‐interacting serine/threonine‐protein kinase 1–mediated necroptosis is induced by nanomolar BPA treatment in SH‐SY5Y cells. This effect is mediated by altered AChE and decreased TNF‐α levels, which result in an apoptosis‐necroptosis switch. Moreover, our study reveals that BPA is an activator of AChE.  相似文献   
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This study aimed to investigate the relationship between endothelial nitric oxide synthase Glu(298)Asp gene polymorphism and hemorheological parameters. Red blood cell (RBC) deformability, aggregation were measured using an ectacytometry, whole blood, plasma viscosities were determined by a viscometer. Restriction fragment length polymorphism was used to detect polymorphism. Plasma nitrite, nitrate concentrations were determined by Griess method. The genotype distribution of the control group was as follows: 50 (67.5%) GG, 21 (28.4%) GT, 3 (4.1%) TT. A 48 (57.8%) of the patients with CAD had GG, 28 (33.7%) GT, 7 (8.5%) of them TT genotype. RBC aggregation index of CAD patients with G allele was higher and t½ lower compared to controls carrying the same allele. The amplitude of RBC aggregation of healthy subjects with T allele, who are under increased cardiovascular risk was lower compared to control subjects with G allele. The results of this study indicate that, alterations in RBC aggregation seem to be a consequence of CAD, more than being a preexisting cause. Additionally, some compensatory mechanisms by causing decrements in RBC aggregation, may help regulation of circulation in healthy individuals with high cardiovascular risk.  相似文献   
6.
We designed a randomized, rater blind study to assess the efficacy of EEG Biofeedback (Neurofeedback-NFB) in patients with fibromyalgia syndrome (FMS). Eighteen patients received twenty sessions of NFB-sensory motor rhythm (SMR) treatment (NFB group) during 4 weeks, and eighteen patients were given 10 mg per day escitalopram treatment (control group) for 8 weeks. Visual Analog Scales for pain and fatigue, Hamilton and Beck Depression and Anxiety Inventory Scales, Fibromyalgia Impact Questionnaire and Short Form 36 were used as outcome measures which were applied at baseline and 2nd, 4th, 8th, 16th, 24th weeks. Mean amplitudes of EEG rhythms (delta, theta, alpha, SMR, beta1 and beta2) and theta/SMR ratio were also measured in NFB group. All post-treatment measurements showed significant improvements in both of the groups (for all parameters p < 0.05). NFB group displayed greater benefits than controls (for all parameters p < 0.05). Therapeutic efficacy of NFB was found to begin at 2nd week and reached to a maximum effect at 4th week. On the other hand, the improvements in SSRI treatment were also detected to begin at 2nd week but reached to a maximum effect at 8th week. No statistically significant changes were noted regarding mean amplitudes of EEG rhythms (p > 0.05 for all). However, theta/SMR ratio showed a significant decrease at 4th week compared to baseline in the NFB group (p < 0.05). These data support the efficacy of NFB as a treatment for pain, psychological symptoms and impaired quality of life associated with fibromyalgia.  相似文献   
7.
Several genes encoding for different cytokines may play crucial roles in host susceptibility to tuberculosis (TB), since the cytokine production capacity varies among individuals and depends on the cytokine gene polymorphism. The association of the cytokine gene polymorphisms with the development of TB was investigated in this study. DNA samples were obtained from a Turkish population of 81 patients with the different clinical forms of TB, and 50 healthy control subjects. All genotyping (IL-6, IL-10, IFN-gamma, TGF-beta and TNF-alpha) experiments were performed using sequence-specific primers PCR (PCR-SSP). Analysis of allele frequencies showed that IL-10 -1082 G allele frequency was significantly more common in TB patients than healthy controls (37.7% vs 23.0%, p: 0.014). No statistically significant differences were observed between the different clinical forms of the disease. These results suggest that the polymorphisms in IL-10 gene may affect susceptibility to TB and increase risk of developing the disease. To confirm the biological significance of our results, further studies should be performed on other population groups.  相似文献   
8.
Biological decolorization of Benazol Black ZN, a reactive azo-type textile dyestuff, was comparatively studied using 3 different commercial-type white rot fungi strains (Pleurotus ostreatus, Pleurotus cornucopiae var. citrinopileatus, Pleurotus djamor, and 2 wild types of P. ostreatus (MCC07 and MCC20) isolated from the nature. The initial dye concentrations in the medium were 500 and 1000 mg.L-1. All the organisms studied decolorized Benazol Black ZN to varying degrees. At low dye concentration, both commercial and wild type of P. ostreatus resulted in the best decolorization, conversely, wild-type P. ostreatus (MCC07) was found to be much more robust against increasing dye concentration and provided the best decolorization efficiency at high dye concentration.  相似文献   
9.
In this study, cultivation of oyster mushroom, Pleurotus ostreatus, on wheat straw substrate containing tap water and olive mill effluent (OME) mixture containing varying volume of OME was studied in order to investigate the feasibility of using OME as an alternative wetting agent and OME's impact on some fundamental food quality characteristics of mushrooms. Time period for mycelial colonization, primordium initiation and first harvest were comparatively evaluated with the control group. It was shown that the use of OME and tap water mixture consisting of OME up to 25% volumetrically was possible for the purpose of commercial mushroom production. Experimental results obtained from substrate containing 25% OME mixture showed no statistically significant difference compared to control group. The negative effects of increasing volume of OME in the mixture were also indicated by bioefficiency, which was found to be 13.8% for substrates wetted with 100% OME, whereas bioefficiency was 53.6% for control group. Increasing volume of OME in the mixture resulted in deformation of fruit body shape, whereas no significant difference in food quality was observed due to the higher amount of OME. This work suggested that the use of OME up to 25% as moisturizer could be considered, especially for the locations having significant number of olive mills and mushroom producers, both as an environmentally friendly solution for the safe and ecological disposal of OME and a practical way for recovering OME's economic value thereby.  相似文献   
10.
Adhesion of four isolates of Candida albicans to buccal epithelial cells was determined after growth of the yeasts in defined medium containing 50 mM glucose or 500 mM galactose as the carbon source. With each isolate, adhesion of galactose-grown yeasts was significantly higher than that of glucose-grown organisms. Yeast cell-surface hydrophobicity was assessed by two methods, a modified hydrocarbon adhesion assay and a more sensitive polystyrene microsphere assay. All four isolates were significantly more hydrophobic after growth on 500 mM galactose than after growth on 50 mM glucose. Overall, a strong positive correlation between adhesion and surface hydrophobicity was observed (r = 0.965). These results are discussed in relation to the role of yeast-surface hydrophobicity in pathogenesis.  相似文献   
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