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991.
992.
Characteristics of spermatogonial stem cells derived from neonatal porcine testis 总被引:1,自引:0,他引:1
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H. Wei X. Zhang L. Li X. C. Tian Q. Jiang C. Wang L. Qin J. Cai S. Zhang 《Andrologia》2015,47(7):765-778
The aim of this study was to isolate and characterise porcine spermatogonial stem cells (PSSCs). The putative porcine germline stem cells from testis were isolated successfully by an improving way of enrichment with lymphocyte separation medium (LSM). Results from RT‐PCR analyses showed that PSSCs were positive for OCT4, SOX2, NANOG, PGP9.5, c‐MYC, KEL4 and PRDM‐14 which are multipotent stem cell markers. At the protein level, the results of immunofluorescence analyses showed that PSSCs were positive for OCT4, PGP9.5, SOX2 and CD29. We successfully differentiated these PSSCs into adipocytes and muscle cells and then defined their characteristics, including morphology, surface stem cell markers, and mechanical properties. But the experiment of teratoma formation was negative. The results indicated the PSSCs could be multipotent. Atomic force microscopy was used to characterise the morphological and mechanical properties of undifferentiated PSSCs, as well as the differentiated adipocytes and muscle cells, which could be potentially useful for distinguishing PSSCs from differentiated cells. 相似文献
993.
OBJECTIVE: To assess the efficacy and safety of cilostazol on the progression and regression of symptomatic intracranial artery stenosis.DATA RETRIVAL: We searched the main databases for eligible trials including Medline(from 1966 to June 2014), Embase(from 1980 to June 2014), Cochrane Library(Issue 6, 2014), Chinese National Knowledge Infrastructure(from 1995 to June 2014), Current Controlled Trials(http://controlled-trials.com), Clinical Trials.gov(http://clinicaltrials.gov), and Chinese Clinical Trial Registry(http://www.chictr.org). All studies regarding prevention and treatment of symptomatic intracranial arterial stenosis by cilostazol were collected. The Mesh or text keywords were the English words: "cilostazol, phosphodiesterase 3 inhibitor, atherosclerosis, and ischemic stroke." No restrictions were put on publications or publication language.SELECTION CRITERIA: Grade A or B randomized controlled trials were selected according to the quality of evaluation criteria from the Cochrane Collaboration, in which cilostazol and aspirin were used to evaluate the effects of cilostazol in the treatment of patients with symptomatic intracranial artery stenosis. The quality of study methodology was evaluated based on criteria described in Cochrane Reviewer's Handbook 5.0.1. Rev Man 5.2 software was used for data analysis.MAIN OUTCOME MEASURES: Clinical efficacy and safety of cilostazol in stopping progression and promoting regression of symptomatic intracranial artery stenosis were measured by magnetic resonance angiography and transcranial Doppler.RESULTS: Two randomized controlled trials with a total of 203 patients were included in this study. The results showed that while cilostazol was associated with a significantly reduced progression of intracranial artery stenosis(OR = 0.21, 95%CI: 0.09–0.47, P 0.01), it had no beneficial effect on symptom regression(OR = 1.42, 95%CI: 0.80–2.51, P = 0.24). During the follow-up period, although some adverse effects developed, including headache, gastrointestinal disturbance, and dizziness, incidences of bleeding were lower than in aspirin-treated patients.CONCLUSION: Cilostazol may prevent the progression of symptomatic intracranial artery stenosis, which could reduce the incidence of ischemic stroke. 相似文献
994.
Yi Cai Jun Liu Li Zhang Mei Liao Yan Zhang Lifeng Wang Hongjun Peng Zhong He Zexuan Li Weihui Li Shaojia Lu Yuqiang Ding Lingjiang Li 《神经科学通报》2015,31(1):4-12
Bipolar disorder and unipolar depressive disorder(UD) may be different in brain structure. In the present study,we performed voxel-based morphometry(VBM) to quantify the grey matter volumes in 23 patients with bipolar I depressive disorder(BP1) and 23 patients with UD,and 23 age-,gender-,and educationmatched healthy controls(HCs) using magnetic resonance imaging. We found that compared with the HC and UD groups,the BP1 group showed reduced grey matter volumes in the right inferior frontal gyrus and middle cingulate gyrus,while the UD group showed reduced volume in the right inferior frontal gyrus compared to HCs. In addition,correlation analyses revealed that the grey matter volumes of these regions were negatively correlated with the Hamilton depression rating scores. Taken together,the results of our study suggest that decreased grey matter volume of the right inferior frontal gyrus is a common abnormality in BP1 and UD,and decreasedgrey matter volume in the right middle cingulate gyrus may be specifi c to BP1. 相似文献
995.
Hongxia Cai Zhihao Mu Zhen Jiang Yongting Wang Guo-Yuan Yang Zhijun Zhang 《神经科学通报》2015,31(5):550-560
Matrix metalloproteinase-9(MMP-9) plays a beneficial role in the sub-acute phase after ischemic stroke.However,unrestrained MMP-9 may disrupt the blood-brain barrier(BBB),which has limited its use for the treatment of brain ischemia.In the present study,we constructed lentivirus mediated hypoxiacontrolled MMP-9 expression and explored its role after stroke.Hypoxia response element(HRE)was used to confine MMP-9 expression only to the hypoxic region of mouse brain after 120-min transient middle cerebral artery occlusion.Lentiviruses were injected into the peri-infarct area on day 7 after transient ischemia.We found hyperexpression of exogenous HRE-MMP-9 under the control of hypoxia,and its expression was mainly located in neurons and astrocytes without aggravation of BBB damage compared to the CMV group.Furthermore,mice in the HRE-MMP-9 group showed the best behavioral recovery compared with the normal saline,GFP,and SB-3CT groups.Therefore,hypoxia-controlled MMP-9 hyperexpression during the sub-acute phase of ischemia may provide a novel promising approach of gene therapy for stroke. 相似文献
996.
997.
Jin Shi Yan Jiayi Cai Hong Zhang Weiming Lu Renhua Zhu Mingli Qi Chaojun Fang Yan Xie Yuanyuan Lu Jiayue Jiang Rong Shao Xinghua Wang Qin Zhou Yijun Ni Zhaohui. 《中华肾脏病杂志》2015,31(10):729-735
Objective To explore the relationship between serum sclerostin level, and mineral metabolism, bone density, abdominal aortic calcification in maintenance hemodialysis (MHD) patients. Methods Serum sclerostin levels from 175 cases of MHD patients were measured by ELISA. Calcaneus bone mineral density (BMD) was measured by quantitative ultrasound (QUS). The abdominal aortic calcification was detected by abdomen lateral plain radiographs. Interrelations among above parameters were examined statistically. Results The median sclerostin concentration of 175 patients was 160.50(100.67, 256.39) pmol/L. Serum sclerostin levels were correlated positively with age, BMI, serum calcium and serum 25(OH)-vitamin D, while negatively with spKt/v and serum iPTH. In multiple regression analysis, serum sclerostin levels were associated significantly and independently with age, sex, BMI and serum iPTH. Compared to patients with normal BMD (T score≥-1s), the patients with low BMD (T score<-1s) had lower serum sclerostin level [142.97(99.52, 226.02) vs 201.13(107.40, 327.84) pmol/L, P=0.035]. Serum sclerostin levels were correlated significantly and positively with calcaneus BMD. Multivariate logistic regression analysis showed that serum sclerostin level was an independent protective factor for low BMD in MHD patients[OR=0.241, 95%CI (0.078, 0.749), P=0.014]. Conclusions Serum sclerostin levels are associated with mineral disorder and bone density. Sclerostin may become a promising marker of bone turnover in MHD patients. 相似文献
998.
目的 观察双氢青蒿素(DHA)对人骨肉瘤细胞活性、转移能力以及细胞中尿激酶型纤溶酶原激活物(uPA)和色素上皮衍生因子(PEDF)表达的影响.方法 将不同浓度的DHA(5、10、20、40、80 μmol/L)作用于体外培养的正常人成骨细胞和人骨肉瘤细胞TE85 12、24、48 h后,噻唑蓝(MTT)法测定DHA对细胞活性的影响,反转录-聚合酶链反应(RT-PCR)法检测细胞中uPA和PEDF mRNA水平的表达,Westen blot法检测uPA和PEDF蛋白水平的表达.结果 DHA对人成骨细胞活性无明显影响(P>0.05).DHA能够明显抑制人骨肉瘤细胞TE85的活性(P<0.05).不同作用时间下DHA对人骨肉瘤细胞TE85的半数抑制浓度(IC50)分别为(12 h)=(41.66±0.53) μmol/L、IC50(24 h)=(32.28 ±0.27)μmol/L和IC50 (48 h)=(22.53±1.26) μmol/L.DHA能够明显减少人骨肉瘤细胞的迁移和细胞中uPA的表达水平,同时细胞中PEDF表达升高(P<0.05).结论 DHA对正常人体骨组织无害,能够有效抑制骨肉瘤细胞生长和转移. 相似文献
999.
Expression of SOCS-1 in the liver tissues of chronic hepatitis B and its clinical significance 总被引:3,自引:0,他引:3
AIM: To study the expression of suppressor of cytokine signaling-1 (SOCS-1) in the liver tissues of chronic hepatitis 13 (CHB) and the clinical significance of this expression. METHODS: The expression of SOCS-1 in liver tissues of 45 cases of CHB was investigated by immunohistochemical staining, and its correlations with inflammation grades and fibrosis stage were analyzed by SPSS statistics software. RESULTS: The result showed SOCS-1 expressing could be observed in the liver tissue of CriB. The expression of SOCS-1 was mainly distributed near the portal area in the liver tissue of mild inflammation CriB group, and was diffusely distributed in the liver tissue of moderate and severe inflammation groups. SOCS-1 positive stains mainly appear in the hepatocytes, only a few of liver interstitial cells were involved. Inside the hepatocyte, SOCS-1 positive stains are mainly distributed in the plasma. Some of the staining was observed on the membrane. The inclusion bodies in the plasma of hepatocytes were observed occasionally. There were both obvious correlations between the expression of SOCS-1 and the inflammatory grade, and that between the expression of SOCS-1 and the fibrosis stage, CONCLUSION: The distribution of SOCS-1 in the liver tissue of CriB is variable. This expression was correlated with the inflammation grade and fibrosis stage. 相似文献
1000.
Basal serum growth hormone and response of GH to GRF in 10 patients with noninsulin-dependent diabetes and in 10 control subjects were studied. The basal GH level in NIDDM was higher than that in control subjects. There was a significant difference. After an intravenous bolus of hGRF 1-29 NH2 with the dose of 1 microgram/kg body weight, GH (Peak level-basal level) decreased in NIDDM patients in comparing with control group (P < 0.05). These findings may suggest that the pituitary GH reserve is reduced in patients with NIDDM. There exists some defect in central GH control in diabetics with enhanced somatostatin secretion and abnormal sensitivity of the GH secretion cells to a variety of regulatory factors including GRF, glucose, amino-acids, free fat acid. 相似文献