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61.
Objective To investigate the differentiation of rat bone marrow mesenchymal stem cells (MSCs) to renal tubular epithelial-like cells under different conditions. Methods MSCs were obtained from rat marrow. MSCs were isolated by gradient density centrifugation and plastic adherence and then purified. Surface markers were identified with flow cytometry after amplification in vitro. The purified MSCs of the third passage were cultured respectively as follows: (1) control group: DMEM medium with fetal bovine serum(FBS). (2) all-trans retinoic acid (ATRA) group: DMEM medium with FBS, ATRA and ischemic reperfusion-injured kidney tissue homogenate. (3)combination group: DMEM medium with FBS, ATRA, ischemic reperfusion-injured kidney tissue homogenate, epidermal growth factor (EGF) and bone morphogenetic protein 7 (BMP-7). After 7 days, the MSCs were collected for alkaline phosphatase (AKP) staining, cytokeratin-18 and E-cadherin immunocytochemical analysis. Results The positive rates of the third passage MSCs in CD44, CD90 and CD29 were 97.8%±0.9%, 96.8%±1.4% and 97.6%±2.4%,respectively, but in CD11b/c and CD34 were only 13.2%±0.6% and 1.2%±0.5%. The MSCs in control group were spindle. The MSCs in ATRA group were round and elliptic. The MSCs in combination group became cobblestone-like cells after 7 days. AKP staining showed that tubular epithelial-like cells from MSCs in control group were negative, some above cells in ATRA group were positive and number of above cells increased in combination group. Compared with negative control group, the ratios of cytokeratin-18 positive cells in ATRA group and combination group were respectively increassed by 29.47%±1.08% and 47.52%±2.13% (all P<0.05), the ratios of E-cadherin positive cells in ATRA group and combination group were respectively increased by 14.88%±2.46% and 36.15%±1.13% (all P<0.05). Conclusion MSCs may differentiate by renal tubular epithelial-like cells under the induction of ischemic reperfusion-injured kidney tissue homogenate and ATRA in vitro, which are further differentiated under the combined induction of EGF and BMP-7.  相似文献   
62.
Background: Although hydrogen peroxide may play an important role in the development of cancer, it can be an efficient inducer of apoptosis in cancer cells; the exact mechanism by which this action occurs is not completely understood in oral cancer cells. Method: In this study, the mechanisms by which H2O2 inhibited growth and induced apoptosis were differentially investigated using HPV‐immortalized human oral keratinocytes (IHOK) and oral cancer cells (HN4). Results: H2O2 treatment sensitively and dose‐dependently induced growth inhibition and typical apoptosis in IHOK and HN4 cells, as demonstrated by a decreased level of cell viability, an increased population of cells in the sub‐G0/G1 phase, ladder formation of the genomic DNA, chromatin condensation and accumulation of Annexin V+/PI+ cells. Furthermore, the expression of Bax, p53 and p21WAF1/CIP1 increased, whereas the expression of Bcl‐2 decreased in immortalized and malignant keratinocytes that were treated with H2O2. In addition, cytochrome‐c from the mitochondria was observed in H2O2‐treated IHOK and oral cancer cells, and this was accompanied by the activation of caspase‐3 and ‐9. Additionally, H2O2 treatment induced upregulation of CHOP, GRP78 and several representative endoplasmic reticulum (ER) stress‐responsive proteins, including heme oxygenase‐1. Conclusion: Overall, these results suggest that H2O2 triggers apoptosis via the mitochondrial and ER stress pathway in IHOK and HN4 cells, and that increasing the cellular levels of H2O2 sufficiently may lead to selective killing of oral cancer cells and therefore be therapeutically useful.  相似文献   
63.
Suggestive associations have been reported between trace amines and heat shock proteins, and a disrupted pathophysiology that enhances the risk of psychosis and that modifies responses to antipsychotic treatments. Our group previously reported genetic studies on TAAR6 and HSP-70 separately in patients with schizophrenia. In the current study, we investigated possible epistasis between the same set of variations in a sample of 281 patients diagnosed with schizophrenia and 288 healthy controls. We applied the generalized multifactor dimensionality reduction (MDR) method and controlled covariates significantly associated with both diagnosis and treatment efficacy. To the best of our knowledge, epistasis between the present set of variations in schizophrenia has not been tested before. We found significant associations with both the risk of disease and response to treatment. However, the insufficiently balanced accuracy of the applied tests suggests that, despite significantly different genetic variations between cases and controls, these factors have a poor predictive value. Explanations for these findings and possible future directions are also discussed.  相似文献   
64.
目的:研究氨基胍(AG)减轻高糖培养系膜细胞(MC)肥大程度与周期素激酶抑制剂P27的关系.方法:Western 印迹方法测定MC裂解液P27水平,[3H]胸腺嘧啶核苷([3H]TdR)及[3H]亮氨酸([3H]Leu)掺入方法测定MC肥大情况.结果:同正常糖(100 mg/dl)培养相比,高糖(450 mg/dl)培养MC中P27水平增高(P<0.01),MC肥大;[3H]Leu掺入增加及[3H]TdR掺入降低(P<0.01);AG(0.25 mmol/L)降低高糖培养MC中P27水平[(2.5±0.6 ) vs (4.0±0.8),P<0.05],使MC肥大程度减轻;[3H]leu掺入降低,[(3 426±532) vs (4 652±309) cpm/孔,P<0.01],[3H]TdR掺入增加[(1 233±69) vs (543±27) cpm/孔,P<0.01].结论:AG可能通过降低高糖培养MC中P27水平减轻MC肥大程度.  相似文献   
65.
Objective To investigate the best way to control the blood sugar level during the perioperation of bone fracture patients with type 2 diabetes(T2DM).Methods Bone fracture patients with T2DM were randomly divided into three groups:continuous subcutaneous insulin infusion group(insulin aspart,group CSII,n=20),glargine treatment group(insulin aspart+insulin glargine,group GA,n=20),and NPH treatment(insulin aspart+rh-insulin,group NA,n=20).The levels of fasting plasma glucose(FPG)and the 2 hours postprandial glucose(2h PG),blood glucose fluctuation(BGF),insulin dosage(ID),good effective time(GET),incidence of hypoglycemia,dawn phenomenon and infection,average time of stitches removal(ATSR),average hospitalized length(AHL)of three groups were compared.Results FPG and 2hPG,ID in group CSII[(6.32±1.18)mmol/L,(7.72±1.53)mmol/L,(35.40±1.60)IU]and group GA [(6.25±0.88)mmol/L,(7.32±1.17)mmol/L,(36.20±0.80)IU]were significantly lower than those of group NA [(7.44±1.36)mmol/L,(8.52±0.76)mmol/L,(40.50±2.40)IU,all P<0.05],simulaneously,BGF,GET incidence of complications,ATSR,AHL of group CSII and GA were significantly lower than those of group NA(all P<0.05).There were not significant difference between group CSII and group GA.Compared with group CSII,group GA had less costs in-hospital and better practicability.Conclusion Both CSII and insulin glargine combined with insulin aspart can effectively,safely,rapidly and stablely control hyperglycemia.and might be the first choice to control blood sugar for bone fracture patients with T2DM in perioperation.  相似文献   
66.
67.
An assessment of the medium term efficacy of stress incontinence cure in a group of patients who had undergone the intravaginal slingplasty (IVS) operation is presented. Eighty-five unselected patients, aged 27 to 83 years at the time of surgery, 12 with pure stress symptoms, and 73 with mixed incontinence symptoms underwent the IVS procedure between 31 and 57 months previously (mean 3.9 years). The patients were assessed with the same self-administered semiquantitative questionnaire used in the initial assessment. The results were compared with the original cure rate which was 88% at 1.75 years with another 2.5% more than 70% improved (total 90.5%). The cure rate in the 75 patients assessed at 3.9 years was 81%, with another 8% reporting more than 70% improvement (total 89%). Included in the latter were 2 patients who, though originally designated as failures, gradually achieved almost 100% continence within 2 years of surgery. Deterioration of continence following the IVS operation appears more like the Burch colposuspension than needle suspensions. It is possible to explain deterioration of continence with time in terms of age-related connective tissue laxity of the vaginal hammock. Improvement in 2 women with time can be explained by tightening of the hammock via paraurethral scar contraction with time. Whether the IVS operation improves or deteriorates in the longer term may depend on which process predominates.  相似文献   
68.
We studied the effect of mokko lactone (ML) isolated from the roots of Saussurea lappa (Compositae), a plant that is used for medicinal purposes in Korea, on the induction of apoptosis in human leukemia HL-60 cells. ML was cytotoxic to HL-60 cells, and this cytotoxic effect of ML appears to be attributable to its induction of apoptotic cell death, as ML induced nuclear morphologic changes and internucleosomal DNA fragmentation and increased the proportion of Annexin V-positive cells and the activity of caspase-3. Further studies revealed that the induction of apoptosis by ML was associated with the loss of mitochondrial membrane potential. Collectively, our results suggest that apoptosis induced by ML in HL-60 cells was executed by a collapse of mitochondrial membrane potential followed by the activation of caspase-3. This is the first report on the mechanism of apoptosis-inducing effect of ML.  相似文献   
69.
目的 比较掌侧锁定接骨板与普通接骨板治疗桡骨远端骨折的长期疗效.方法 对2005年9月-2007年11月间,采用切开复位掌侧锁定接骨板或普通接骨板内固定的45例随访资料完整的患者,进行两种疗法的比较.其中23例行锁定接骨板内固定,22例行普通接骨板内固定.按照AO分型:A型11例,B型11例,C型23例.随访内容包括:腕关节活动度(屈曲、背伸、尺偏、桡偏),前臂旋前、旋后活动范围,影像学资料(尺偏角、掌倾角、桡骨高度),应用DASH上肢功能评定标准和Gartland/Wertey腕关节评分法进行评分.结果 术后随访时间平均为18.8个月(12~36个月).腕关节活动度中,锁定板组背伸及两组的桡偏范围低于Gartland/Werley腕关节评分的基本范围.两组DASH值、腕关节活动度及前臂旋转范围,握力、捏力的恢复差异无统计学意义.Gartland/Werley腕关节评分普通接骨板治疗组优于锁定接骨板治疗组,差异有统计学意义.掌倾角均值两组都低于正常范围,尺偏角与桡骨高度均值在正常范围内,两组间差异无统计学意义.结论 掌侧锁定接骨板与普通接骨板在桡骨远端骨折治疗中具有相同疗效.  相似文献   
70.
Objective To investigate the differentiation of rat bone marrow mesenchymal stem cells (MSCs) to renal tubular epithelial-like cells under different conditions. Methods MSCs were obtained from rat marrow. MSCs were isolated by gradient density centrifugation and plastic adherence and then purified. Surface markers were identified with flow cytometry after amplification in vitro. The purified MSCs of the third passage were cultured respectively as follows: (1) control group: DMEM medium with fetal bovine serum(FBS). (2) all-trans retinoic acid (ATRA) group: DMEM medium with FBS, ATRA and ischemic reperfusion-injured kidney tissue homogenate. (3)combination group: DMEM medium with FBS, ATRA, ischemic reperfusion-injured kidney tissue homogenate, epidermal growth factor (EGF) and bone morphogenetic protein 7 (BMP-7). After 7 days, the MSCs were collected for alkaline phosphatase (AKP) staining, cytokeratin-18 and E-cadherin immunocytochemical analysis. Results The positive rates of the third passage MSCs in CD44, CD90 and CD29 were 97.8%±0.9%, 96.8%±1.4% and 97.6%±2.4%,respectively, but in CD11b/c and CD34 were only 13.2%±0.6% and 1.2%±0.5%. The MSCs in control group were spindle. The MSCs in ATRA group were round and elliptic. The MSCs in combination group became cobblestone-like cells after 7 days. AKP staining showed that tubular epithelial-like cells from MSCs in control group were negative, some above cells in ATRA group were positive and number of above cells increased in combination group. Compared with negative control group, the ratios of cytokeratin-18 positive cells in ATRA group and combination group were respectively increassed by 29.47%±1.08% and 47.52%±2.13% (all P<0.05), the ratios of E-cadherin positive cells in ATRA group and combination group were respectively increased by 14.88%±2.46% and 36.15%±1.13% (all P<0.05). Conclusion MSCs may differentiate by renal tubular epithelial-like cells under the induction of ischemic reperfusion-injured kidney tissue homogenate and ATRA in vitro, which are further differentiated under the combined induction of EGF and BMP-7.  相似文献   
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