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Characteristic pathological changes in osteonecrosis of the femoral head (ONFH) include reduced osteogenic differentiation of bone mesenchymal stem cells (BMSCs), impaired osseous circulation and increased intramedullary adipocytes deposition. Osthole is a bioactive derivative from coumarin with a wide range of pharmacotherapeutic effects. The aim of this study was to unveil the potential protective role of osthole in alcohol‐induced ONFH. In vitro, ethanol (50 mmol/L) remarkably decreased the proliferation and osteogenic differentiation of BMSCs and impaired the proliferation and tube formation capacity of human umbilical vein endothelial cell (HUVECs), whereas it substantially promoted the adipogenic differentiation of BMSCs. However, osthole could reverse the effects of ethanol on osteogenesis via modulating Wnt/β‐catenin pathway, stimulate vasculogenesis and counteract adipogenesis. In vivo, the protective role of osthole was confirmed in the well‐constructed rat model of ethanol‐induced ONFH, demonstrated by a cascade of radiographical and pathological investigations including micro‐CT scanning, haematoxylin‐eosin staining, TdT‐mediated dUTP nick end labelling, immunohistochemical staining and fluorochrome labelling. Taken together, for the first time, osthole was demonstrated to rescue the ethanol‐induced ONFH via promoting bone formation, driving vascularization and retarding adipogenesis.  相似文献   
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Liu  Junwei  Bao  Yixuan  Zhang  Xuan  Zhang  Kaiyun  Chen  Shuaimin  Wu  Haiyan  He  Jian 《Antonie van Leeuwenhoek》2021,114(10):1541-1549
Antonie van Leeuwenhoek - An obligate anaerobic bacterial BAD-10 T was isolated from anaerobic acetochlor-degrading sludge. The strain was Gram-stain negative, curved rod-shaped,...  相似文献   
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Zhai  Wenjie  Zhou  Xiuman  Zhai  Mingxia  Li  Wanqiong  Ran  Yunhui  Sun  Yixuan  Du  Jiangfeng  Zhao  Wenshan  Xing  Lingxiao  Qi  Yuanming  Gao  Yanfeng 《中国科学:生命科学英文版》2021,64(4):548-562
The interaction of PD-1/PD-L1 allows tumor cells to escape from immune surveillance. Clinical success of the antibody drugs has proven that blockade of PD-1/PD-L1 pathway is a promising strategy for cancer immunotherapy. Here, we developed a cyclic peptide C8 by using Ph.D.-C7 C phage display technology. C8 showed high binding affinity with h PD-1 and could effectively interfere the interaction of PD-1/PD-L1. Furthermore, C8 could stimulate CD8+T cell activation in human peripheral blood mononuclear cells(PBMCs). We also observed that C8 could suppress tumor growth in CT26 and B16-OVA, as well as anti-PD-1 antibody resistant B16 mouse model. CD8+T cells infiltration significantly increased in tumor microenvironment, and IFN-γ secretion by CD8+T cells in draining lymph nodes also increased. Simultaneously, we exploited T cells depletion models and confirmed that C8 exerted anti-tumor effects via activating CD8+T cells dependent manner. The interaction model of C8 with h PD-1 was simulated and confirmed by alanine scanning. In conclusion, C8 shows anti-tumor capability by blockade of PD-1/PD-L1 interaction, and C8 may provide an alternative candidate for cancer immunotherapy.  相似文献   
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PurposeTo characterize cerebral glucose metabolism associated with different cognitive states in Parkinson’s disease (PD) using 18F-fluorodeoxyglucose (FDG) and Positron Emission Tomography (PET).MethodsThree groups of patients were recruited in this study including PD patients with dementia (PDD; n = 10), with mild cognitive impairment (PD-MCI; n = 20), and with no cognitive impairment (PD-NC; n = 30). The groups were matched for age, sex, education, disease duration, motor disability, levodopa equivalent dose and Geriatric Depression Rating Scale (GDS) score. All subjects underwent a FDG-PET study. Maps of regional metabolism in the three groups were compared using statistical parametric mapping (SPM5).ResultsPD-MCI patients exhibited limited areas of hypometabolism in the frontal, temporal and parahippocampal gyrus compared with the PD-NC patients (p < 0.01). PDD patients had bilateral areas of hypometabolism in the frontal and posterior parietal-occipital lobes compared with PD-MCI patients (p < 0.01), and exhibited greater metabolic reductions in comparison with PD-NC patients (p < 0.01).ConclusionsCompared with PD-NC patients, hypometabolism was much higher in the PDD patients than in PD-MCI patients, mainly in the posterior cortical areas. The result might suggest an association between posterior cortical hypometabolism and more severe cognitive impairment. PD-MCI might be important for early targeted therapeutic intervention and disease modification.  相似文献   
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The impact of paternal age on reproduction, especially using assisted reproductive technologies, has not been well studied to date. To investigate the effect of paternal age on reproductive outcomes, here we performed a retrospective analysis of 2,627 intracytoplasmic sperm injection (ICSI) cycles performed at the Reproductive Medicine Center of the Third Affiliated Hospital of Guangzhou Medical University (China) between January 2007 and May 2015. Effect of paternal age on embryo quality [number of fertilized oocytes, 2 pronucleus zygotes (2PNs), viable embryos, and high-quality embryos] was analyzed by multiple linear regression. Relationships between paternal age and pregnancy outcomes were analyzed by binary logistic regression. After adjusting for female age, no association between paternal age and the following parameters of embryo quality was observed: number of fertilized oocytes (B = -0.032; 95% CI -0.069–0.005; P = 0.088), number of 2PNs (B = -0.005; 95% CI -0.044–0.034; P = 0.806), and number of viable embryos (B = -0.025; 95% CI -0.052–0.001; P = 0.062). However, paternal age negatively influenced the number of high-quality embryos (B = -0.020; 95% CI -0.040–0.000; P = 0.045). Moreover, paternal age had no effect on pregnancy outcomes (OR for a 5-year interval), including the rates of clinical pregnancy (OR 0.919; 95% CI 0.839–1.006; P = 0.067), ongoing pregnancy (OR 0.914; 95% CI 0.833–1.003; P = 0.058), early pregnancy loss (OR 1.019; 95% CI 0.823–1.263; P = 0.861), live births (OR 0.916; 95% CI 0.833–1.007; P = 0.070), and preterm births (OR 1.061; 95% CI 0.898–1.254; P = 0.485). Therefore, increased paternal age negatively influences the number of high-quality embryos, but has no effect on pregnancy outcomes in couples undergoing ICSI cycles. However, more studies including men aged over 60 years with a longer-term follow-up are needed.  相似文献   
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Obesity and its associated metabolic disorders such as diabetes, hepatic steatosis and chronic heart diseases are affecting billions of individuals. However there is no satisfactory drug to treat such diseases. In this study, we found that alisol A, a major active triterpene isolated from the Chinese traditional medicine Rhizoma Alismatis, could significantly attenuate high‐fat‐diet‐induced obesity. Our biochemical detection demonstrated that alisol A remarkably decreased lipid levels, alleviated glucose metabolism disorders and insulin resistance in high‐fat‐diet‐induced obese mice. We also found that alisol A reduced hepatic steatosis and improved liver function in the obese mice model.In addition, protein expression investigation revealed that alisol A had an active effect on AMPK/ACC/SREBP‐1c pathway. As suggested by the molecular docking study, such bioactivity of alisol A may result from its selective binding to the catalytic region of AMPK.Therefore, we believe that Alisol A could serve as a promising agent for treatment of obesity and its related metabolic diseases.  相似文献   
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Ku Y  Ohara S  Wang L  Lenz FA  Hsiao SS  Bodner M  Hong B  Zhou YD 《PloS one》2007,2(8):e771
Our previous studies on scalp-recorded event-related potentials (ERPs) showed that somatosensory N140 evoked by a tactile vibration in working memory tasks was enhanced when human subjects expected a coming visual stimulus that had been paired with the tactile stimulus. The results suggested that such enhancement represented the cortical activities involved in tactile-visual crossmodal association. In the present study, we further hypothesized that the enhancement represented the neural activities in somatosensory and frontal cortices in the crossmodal association. By applying independent component analysis (ICA) to the ERP data, we found independent components (ICs) located in the medial prefrontal cortex (around the anterior cingulate cortex, ACC) and the primary somatosensory cortex (SI). The activity represented by the IC in SI cortex showed enhancement in expectation of the visual stimulus. Such differential activity thus suggested the participation of SI cortex in the task-related crossmodal association. Further, the coherence analysis and the Granger causality spectral analysis of the ICs showed that SI cortex appeared to cooperate with ACC in attention and perception of the tactile stimulus in crossmodal association. The results of our study support with new evidence an important idea in cortical neurophysiology: higher cognitive operations develop from the modality-specific sensory cortices (in the present study, SI cortex) that are involved in sensation and perception of various stimuli.  相似文献   
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