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61.
Epigenetic dysregulation plays a crucial role in cardiovascular diseases. Previously, we reported that acetyltransferase p300 (ATp300) inhibitor L002 prevents hypertension‐induced cardiac hypertrophy and fibrosis in a murine model. In this short communication, we show that treatment of hypertensive mice with ATp300‐specific small molecule inhibitor L002 or C646 reverses hypertension‐induced left ventricular hypertrophy, cardiac fibrosis and diastolic dysfunction, without reducing elevated blood pressures. Biochemically, treatment with L002 and C646 also reverse hypertension‐induced histone acetylation and myofibroblast differentiation in murine ventricles. Our results confirm and extend the role of ATp300, a major epigenetic regulator, in the pathobiology of cardiac hypertrophy and fibrosis. Most importantly, we identify the efficacies of ATp300 inhibitors C646 and L002 in reversing hypertension‐induced cardiac hypertrophy and fibrosis, and discover new anti‐hypertrophic and anti‐fibrotic candidates.  相似文献   
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Toluene is used widely, not only in industry, but also in households where toluene exposure and abuse can occur. To estimate the genotoxic risk of toluene exposure, DNA damage was determined in peripheral lymphocytes of 20 glue sniffers and 20 age-matched controls by use of the alkaline comet assay. Urinary hippuric acid and o-cresol excretion rates, which are used as a marker for toluene exposure, were also measured in sniffers and compared with historical control values. The increase in genetic damage in sniffers was statistically significant as compared to control subjects (P<0.0001). The mean values of the hippuric acid and o-cresol excretion rate for glue sniffers was 73- and 1582-fold higher, respectively, than in controls and confirms the putative exposure. Education of the general public and efforts to keep adolescents away from volatile solvent-based products, which may lead to a desire of sniffing in the future, would be advisable.  相似文献   
64.
OBJECTIVE: To investigate possible detrimental effects on bone tissue induced by ovariectomy and tamoxifen (TMX) using bone densitometry and histomorphologic analysis. STUDY DESIGN: Twenty-four rats were allocated into 4 groups: group 1, intact normal rats (n = 6); group 2, ovariectomized rats (n = 6); group 3, normal female rats that received 1 mg/kg/day TMX dissolved in dimethyl sulfoxide (DMSO) for 2 months (n = 6); group 4, normal female rats that received DMSO for the same duration and with a volume equal to that of TMX (n = 6). Results of histomorphometric analysis for trabecular thickness, number of osteoblasts and osteoclasts, trabecular number, and area and cortical thickness were compared. RESULTS: No significant effects of ovariectomy on femoral or lumbar bone mineral density (BMD) were found. In the TMX group, the value of femoral BMD increased significantly compared to control group cellular and pathologic changes. TMX caused significant decrease in osteoblasts compared to the control group. CONCLUSION: TMX has a positive effect on inorganic bone tissue, but a negative effect on number of osteoblasts and osteoclasts. Future studies investigating estrogenic and antiestrogenic effects of TMX should include cellular parameters related to proliferation using histopathologic and histomorphometric analyses.  相似文献   
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We investigated abnormalities of the hypothalamic–pituitary–gonadal axis and cortisol concentrations in women with fibromyalgia and chronic fatigue syndrome (CFS) who were in the follicular phase of their menstrual cycle, and whether their scores for depressive symptoms were related to levels of these hormones. A total of 176 subjects participated – 46 healthy volunteers, 68 patients with fibromyalgia, and 62 patients with CFS. We examined concentrations of follicle-stimulating hormone, luteinizing hormone (LH), estradiol, progesterone, prolactin, and cortisol. Depressive symptoms were assessed using the Beck Depression Inventory (BDI). Cortisol levels were significantly lower in patients with fibromyalgia or CFS than in healthy controls (P < 0.05); there were no significant differences in other hormone levels between the three groups.  相似文献   
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Crimean-Congo hemorrhagic fever (CCHF) is an increasing health concern in Turkey since 2002. There were also some recent human cases from the South Marmara region of Turkey; thus, a tick survey was performed, and possible vector tick species for the CCHF virus were determined in the region. A total of 740 adult ticks were collected from infested livestock from five locations: Çanakkale-Biga, Bursa-Orhaneli, Bursa-Keles, Bal?kesir and Bilecik. Total of 11 tick species from the genera Hyalomma, Rhipicephalus, Dermacentor, Ixodes and Haemaphysalis were identified. Rhipicephalus ticks were dominant in the region; the most frequently observed tick species was R. turanicus, (53.1 %), and only 15.4 % of the identified ticks were H. marginatum. The occurrence of H. rufipes infestation in the region fort he first time. A total of 73 pools of adult ticks were tested with both an antigen-detecting ELISA and RT real-time PCR (RT rt PCR). The presence of the CCHF virus was demonstrated in 9 (12.3 %) of the tested tick pools. Although seven of the tick pools were positive for the CCHF virus with both of the methods, one pool was positive only with RT rt PCR and the other pool was only positive with the ELISA. Positive results were obtained from ticks collected from cattle, sheep and goats from two locations, Bursa-Orhaneli and Bilecik. The CCHF virus was detected in R. turanicus (n = 3), R. bursa (n = 2), H. marginatum (n = 2) and D. marginatus (n = 2) ticks. The results of this study confirm the presence of the CCHF virus and present preliminary data on the vector tick species in the southern Marmara region of Turkey.  相似文献   
68.
The natural polyphenolic compound resveratrol (3,4,5-trihydroxy-trans-stilbene) has broad spectrum health beneficial activities including antioxidant, anti-inflammatory, anti-aging, anti-cancer, cardioprotective, and neuroprotective effects. Remarkably, resveratrol also induces apoptosis and cellular senescence in primary and cancer cells. Resveratrol’s anti-aging effects both in vitro and in vivo attributed to activation of a (NAD)-dependent histone deacetylase family member sirtuin-1 (SIRT1) protein. In mammals seven members (SIRT1-7) of sirtuin family have been identified. Among those, SIRT1 is the most extensively studied with perceptive effects on mammalian physiology and suppression of the diseases of aging. Yet no data has specified the role of sirtuins, under conditions where resveratrol treatment induces senescence. Current study was undertaken to investigate the effects of resveratrol in human primary dermal fibroblasts (BJ) and to clarify the role of sirtuin family members in particular SIRT1 and SIRT2 that are known to be involved in cellular stress responses and cell cycle, respectively. Here, we show that resveratrol decreases proliferation of BJ cells in a time and dose dependent manner. In addition the increase in senescence associated β-galactosidase (SA-β-gal) activity and methylated H3K9-me indicate the induction of premature senescence. A significant increase in phosphorylation of γ-H2AX, a surrogate of DNA double strand breaks, as well as in levels of p53, p21CIP1 and p16INK4A is also detected. Interestingly, at concentrations where resveratrol induced premature senescence we show a significant decrease in SIRT1 and SIRT2 levels by Western Blot and quantitative RT-PCR analysis. Conversely inhibition of SIRT1 and SIRT2 via siRNA or sirtinol treatment also induced senescence in BJ fibroblasts associated with increased SA-β-gal activity, γ-H2AX phosphorylation and p53, p21CIP1 and p16INK4A levels. Interestingly DNA damaging agent doxorubicin also induced senescence in BJ fibroblasts associated with decreased SIRT1/2 levels. In conclusion our data reveal that resveratrol induced premature senescence is associated with SIRT1 and SIRT2 down regulation in human dermal fibroblasts. Here we suggest that the concomitant decline in SIRT1/2 expression in response to resveratrol treatment may be a cause for induction of senescence, which is most likely mediated by a regulatory mechanism activated by DNA damage response.  相似文献   
69.
The predator beetle Rhizophagus grandis Gyll. (Coleoptera, Rhizophaginae) is one of the most important biological control agents, mass-bred and used to suppress populations of an important pest: the great spruce bark beetle, Dendroctonus micans. The achlorophyllous alga Helicosporidium sp. was first discovered in the pest. Later it was also found in the predator, but only in the adults. In this study, the pathogenic alga Helicosporidium sp. was discovered in larvae and early pupae of R. grandis for the first time. The morphological characteristics of the pathogenic alga were revealed by light and electron microscopy. Infection rates of Helicosporidium sp. in the larvae and pupae of R. grandis were 23.5% and 6.25%, respectively.  相似文献   
70.
The purpose of this study is to investigate the relationship between the blood level of cadmium and the occurrence of ectopic pregnancy. Forty-one (41) case patients with ectopic pregnancy and 41 uncomplicated intrauterine pregnant patients as controls were recruited. The concentrations of cadmium (Cd) were measured from blood samples using atomic absorption spectrometry. The cases and controls were similar in age, body mass index, and smoking habits. The median blood level of Cd was 0.32 μg/l (interquartile range [IQR] 0.00–0.71) in the women with ectopic pregnancies and 0.34 μg/l (IQR 0.09–0.59) in the controls. There was no significant association between blood cadmium levels and ectopic pregnancy.  相似文献   
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