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Melatonin is reportedly associated with intervertebral disc degeneration (IDD). Endplate cartilage is vitally important to intervertebral discs in physiological and pathological conditions. However, the effects and mechanism of melatonin on endplate chondrocytes (EPCs) are still unclear. Herein, we studied the effects of melatonin on EPC apoptosis and calcification and elucidated the underlying mechanism. Our study revealed that melatonin treatment decreases the incidence of apoptosis and inhibits EPC calcification in a dose‐dependent manner. We also found that melatonin upregulates Sirt1 expression and activity and promotes autophagy in EPCs. Autophagy inhibition by 3‐methyladenine reversed the protective effect of melatonin on apoptosis and calcification, while the Sirt1 inhibitor EX‐527 suppressed melatonin‐induced autophagy and the protective effects of melatonin against apoptosis and calcification, indicating that the beneficial effects of melatonin in EPCs are mediated through the Sirt1‐autophagy pathway. Furthermore, melatonin may ameliorate IDD in vivo in rats. Collectively, this study revealed that melatonin reduces EPC apoptosis and calcification and that the underlying mechanism may be related to Sirt1‐autophagy pathway regulation, which may help us better understand the association between melatonin and IDD.  相似文献   
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Biomechanics and Modeling in Mechanobiology - Planar biaxial testing is commonly used to characterize the mechanical properties of arteries, but stresses associated with specimen flattening during...  相似文献   
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The present study evaluates the groundwater quality for drinking and agricultural purposes and determines physicochemical characteristics of groundwater in the Sistan and Baluchistan province in Iran. In order to investigate the water quality, sampling was done in 654 open dug wells, the chemical parameters were analyzed, and water quality index was determined. In this regard, Langelier saturation index (LSI), Ryznar Stability index (RSI), Puckorius scaling index (PSI), Larson–Skold index (LS), and Aggressiveness index (AI) were considered to determine water suitability for industrial purposes. Finally, the analytical results were taken to generate the numerical spatial distribution of the parameters using the geographic information system (GIS) environment. According to the results, water sources were less corrosive based on AI and PSI, low and light corrosion according to RSI, and corrosion according to the Larsson–Sckold index. The results of the drinking water quality index showed that 1.2% shared extraction wells were classified as excellent, 52.1% as good, 39% as poor, 6% as very poor, and 1.7% as unsuitable for drinking purpose classes. In addition, irrigating water quality index illustrated that 19.9% and 80.1% wells were placed in the “excellent” and “Good” classes, respectively. Also, the quality of water in this study was categorized as brackish.  相似文献   
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Cerium oxide nanoparticles are associated with anticancer effects. While protecting normal cells, these nanoparticles exert their anticancer effects via oxidative stress and apoptosis in the cancer cells. In this study, the anticancer properties of nanoceria on fibrosarcoma cell line are evaluated. Cerium oxide nanoparticles were synthesized by the coprecipitation method and their anticancer effects on mouse fibrosarcoma tumor cells (WEHI164) were investigated. Viability assay was evaluated by MTT, and the DC-FDA assay performed for the detection of reactive oxygen species. For apoptosis assay, the annexin V/PI test was done as well as measuring the mRNA and protein expression levels of Bax and Bcl2 by real-time PCR and western blot method, respectively. Characterization of nanoceria reveals that synthesized nanoceria has cubic floruit structure with a size of about 30 nm. Toxicity assessment results show that nanoceria increases ROS levels and induced apoptosis in a dose-dependent manner in cancer cells (WEHI164), whereas low levels of toxicity were observed in normal cells (L929), even at the concentrations above 250 µg/ml in MTT assay. Real-time PCR and western blot assays showed that nanoceria could significantly increase the Bax expression in cancer cells. The results showed that nanoceria could act as a potential therapeutic agent for the treatment of fibrosarcoma.  相似文献   
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Heat-shock protein 27 (HSP27) is a chaperone molecule that plays a critical role in the refolding and activity of several proteins responsible for cancer cell drug toxicity. Upregulation of HSP27 is associated with decreased drug sensitivity as well as poorer survival in gastrointestinal (GI) malignancies. It is, therefore, possible that HSP27 may be of value in the assessment of prognostic and therapeutic efficacy in the treatment of GI cancers. Pharmacological and biological inhibitors of HSP27 enhance tumor cell chemosensitivity. This review summarizes the potential role of HSP27 in chemotherapy drug resistance and the therapeutic potential of HSP27 inhibitors as a novel strategy in the treatment of GI cancers.  相似文献   
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Prostate cancer is a major cause of cancer-related death in males. Wnt/β-catenin signaling plays a critical role in the pathogenesis of this disease by regulating angiogenesis, drug resistance, cell proliferation, and apoptosis. Suppression of Wnt canonical or noncanonical signaling pathways via Wnt biological or pharmacological antagonists is a potentially novel therapeutic approach for patients with prostate cancer. This review summarizes the role of Wnt signaling inhibitors in the pathogenesis of prostate cancer for a better understanding and hence a better management of this disease.  相似文献   
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Poor wound healing is a highly prevalent clinical problem with, as yet, no entirely satisfactory solution. A new technique, termed electrospinning, may provide a solution to improve wound healing. Due to their large surface area to volume ratio and porosity, the nanofibers created by electrospinning are able to deliver sustained drug release and oxygen to the wound. Using different types of polymers with varying properties helps strengthening nanofiber and exudates absorption. The nanofibers appear to have an ideal structure applicable for wound healing and, in combination with curcumin, can blend the anti-inflammatory and antioxidant properties of curcumin into a highly effective wound dressing. The use of suitable curcumin solvents and the slow release of curcumin from the nanofiber help in overcoming the known limitations of curcumin, specifically its low stability and limited bioavailability. Here, we review the studies which have been done on synthesized nanofibers containing curcumin, produced by the electrospinning technique, for the purpose of wound healing.  相似文献   
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