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71.
Bladder cancer (BC) is a lethal cancer that threatens the health of millions of people. Chemotherapy drug resistance, for example, cisplatin (DDP) resistance, is a huge limitation for BC therapy. PTEN pseudogene-1 (PTENP1) has been identified as a significant biomarker of multiple cancers. Therefore, it is essential to illuminate the molecular mechanism of PTENP1 in BC cell DDP resistance and progression. Serum exosomes were isolated using an ExoQuick precipitation kit. Serum exosomes were round-shaped vesicles of 100 ± 60 nm in size. The expression of PTENP1 was down-regulated in serum exosomes isolated from cisplatin non-responsive patients compared with responsive patients. ROC curves certified the diagnostic value of PTENP1. Apparently, PTENP1 transfection inhibited DDP-resistant BC cell proliferation, migration, cisplatin resistance and facilitated apoptosis. Next, we discovered that PTENP1 was a sponge of miR-103a, while PDCD4 was a target of miR-103a. More importantly, PTENP1 regulated DDP-resistant cell viability, migration, apoptosis and cisplatin resistance by interacting with the miR-103a/PDCD4 axis. In addition, PTENP1 hindered tumor growth of cisplatin-resistant mice. Exosome-derived PTENP1 suppressed the DDP resistance of BC by inhibiting cell proliferation, migration and promoting apoptosis through regulating the miR-103a/PDCD4 axis, representing a targeted therapy for DDP-resistant BC patients.

Bladder cancer (BC) is a lethal cancer that threatens the health of millions of people.  相似文献   
72.
目的探讨西安地区部分人群肺功能的特点,生活习惯和环境等因素与肺功能的关系。方法2012年7—8月对西安地区东郊和北郊共405人进行问卷调查和肺功能检测,并用多元逐步回归分析不同因素对肺功能指标的影响。结果西安地区东郊和北郊人群FVC,PEF和FEF25—75均低于正常预计值,东郊和北郊人群之间肺功能主要指标差异有统计学意义(P〈0.001);肺功能主要指标与年龄增长、性别和肺部疾病呈负相关(P〈0.05)。结论西安地区部分人群肺功能主要指标偏低,为今后该地区呼吸系统疾病防治提供依据。  相似文献   
73.
Standardized Ginkgo biloba leaf extract has been used in clinical trials for its beneficial effects on brain functions,particularly in dementia.Substantial experimental evidences indicated that Ginkgo biloba leaf extract (EGB) protected neuronal cells from a variety of insults.We investigated the effect of EGB on cognitive ability and protein kinase B (PKB) activity in hippocampal neuronal cells of dementia model rats.Rats received an intraperitoneal injection of D-galactose to induce dementia.Forty-eight Spraque-Dawley rats were randomly divided into six groups,including the control group,D-galactose group (Gal),low-dose EGB group (EGB-L),mid-dose EGB group (EGB-M),high-dose EGB group (EGB-H) and treatment group.The EGB-L,EGB-M and EGB-H groups were administered with EGB and D-galactose simultaneously.Y-maze,cresyl violet staining,TUNEL assays and immunohistochemistry staining were performed to detect learning and memory abilities,morphological changes in the hippocampus,neuronal apoptosis and the expressing level of phospho-PKB,respectively.Rats in the Gal group showed decreased abilities of learning and memory,and hippocampal pyramidal cell layer was damaged,while EGB administration improved learning and memory abilities.The Gal group exhibited many stained,condensed nuclei and micronuclei,either isolated or within the cytoplasm of cells (39.5±1.4).Apoptotic cells decreased in the groups of EGB-L (35.9±0.9),EGB-M (16.8±1.0) and EGB-H (10.1±0.8),and there were statistical significances compared with the Gal group.Immunoreactivity of phospho-PKB was localized diffusely throughout the cytosol of cells in all groups,while the immunoreactivity of the Gal group was weak.EGB significantly attenuated learning and memory impairment in a dose-dependent manner,while it could decrease the nmber of TUNEL-positive cells,and increase the activity of PKB.Our results demonstrated that EGB attenuated memory impairment and cell apoptosis in galactose-induced dementia model rats by activating PKB.  相似文献   
74.
Antigens encoded in the region of difference (RD) of Mycobacterium tuberculosis constitute a potential source of specific immunodiagnostic antigens for distinguishing tuberculosis (TB) infection from BCG vaccination. We evaluated the diagnostic potential of specific T-cell epitopes selected from two immunodominant antigens, Rv1985c and Rv3425, from RD2 and RD11, respectively, on the basis of epitope mapping, in TB patients and BCG-vaccinated healthy individuals. Using a whole-blood gamma interferon release assay, a wide array of epitopes was recognized on both Rv1985c and Rv3425 in TB patients. Those epitopes that could specifically discriminate TB infection from BCG vaccination were carefully selected, and the most promising peptide pools from Rv1985c showed a sensitivity of 53.9% and a specificity of 95.5%. When the novel specific peptides from Rv1985c joined the diagnostic antigens in the QuantiFERON-TB Gold In-Tube (QFT-IT) assay, the sensitivity was increased from 86.4% to 96.2%, with no drop in specificity. These results indicate that the peptide pools selected from Rv1985c and Rv3425 have the potential to diagnose TB infection by a method that may be routinely used in clinical laboratories.  相似文献   
75.
AIM: To evaluate immunological protection of nitric oxide (NO) in hepatopulmonary syndrome and probable mechanisms of ischemia-reperfusion (IR) injury in rat liver transplantation.METHODS: Sixty-six healthy male Wistar rats were randomly divided into three groups (11 donor/recipient pairs). In group II, organ preservation solution was lactated Ringer’s solution with heparin 10  000/μL at 4 °C. In groups I and III, the preservation solution added, respectively, L-arginine or NG-L-arginine methyl ester (L-NAME) (1 mmol/L) based on group II, and recipients were injected with L-arginine or L-NAME (50 mg/kg) in the anhepatic phase. Grafted livers in each group were stored for 6 h and implanted into recipients. Five rats were used for observation of postoperative survival in each group. The other six rats in each group were used to obtain tissue samples, and executed at 3 h and 24 h after transplantation. The levels of alanine aminotransferase (ALT), tumor necrosis factor (TNF)-α and NO metabolites (NOx) were detected, and expression of NO synthase, TNF-α and intercellular adhesion molecule 1 (ICAM-1) was examined by triphosphopyridine nucleotide diaphorase histochemical and immunohistochemical staining.RESULTS: By supplementing L-arginine to strengthen the NO pathway, a high survival rate was achieved and hepatic function was improved. One-week survival rate of grafted liver recipients in group I was significantly increased (28.8 ± 36.6 d vs 4 ± 1.7 d, P < 0.01) as compared with groups II and III. Serum levels of ALT in group I were 2-7 times less than those in groups II and III (P < 0.01). The cyclic guanosine monophosphate (cGMP) levels in liver tissue and NOx in group I were 3-4 times higher than those of group II after 3 h and 24 h reperfusion, while in group III, they were significantly reduced as compared with those in group II (P < 0.01). The levels of TNF-α in group I were significantly lower than in group II after 3 h and 24 h reperfusion (P < 0.01), while being significantly higher in group III than group II (P < 0.01). Histopathology revealed more severe tissue damage in graft liver and lung tissues, and a more severe inflammatory response of the recipient after using NO synthase inhibitor, while the pathological damage to grafted liver and the recipient’s lung tissues was significantly reduced in group I after 3 h and 24 h reperfusion. A small amount of constitutive NO synthase (cNOS) was expressed in liver endothelial cells after 6 h cold storage, but there was no expression of inducible NO synthase (iNOS). Expression of cNOS was particularly significant in vascular endothelial cells and liver cells at 3 h and 24 h after reperfusion in group II, but expression of iNOS and ICAM-1 was low in group I. There was diffuse strong expression of ICAM-1 and TNF-α in group III at 3 h after reperfusion.CONCLUSION: The NO/cGMP pathway may be critical in successful organ transplantation, especially in treating hepatopulmonary syndrome during cold IR injury in rat orthotopic liver transplantation.  相似文献   
76.
AIM: To investigate the protective effect and mechanism of rebamipide on small intestinal permeability induced by diclofenac in mice.METHODS: Diclofenac (2.5 mg/kg) was administered once daily for 3 d orally. A control group received the vehicle by gavage. Rebamipide (100 mg/kg, 200 mg/kg, 400 mg/kg) was administered intragastrically once a day for 3 d 4 h after diclofenac administration. Intestinal permeability was evaluated by Evans blue and the FITC-dextran method. The ultrastructure of the mucosal barrier was evaluated by transmission electron microscopy (TEM). Mitochondrial function including mitochondrial swelling, mitochondrial membrane potential, mitochondrial nicotinamide adenine dinucleotide-reduced (NADH) levels, succinate dehydrogenase (SDH) and ATPase activities were measured. Small intestinal mucosa was collected for assessment of malondialdehyde (MDA) content and myeloperoxidase (MPO) activity.RESULTS: Compared with the control group, intestinal permeability was significantly increased in the diclofenac group, which was accompanied by broken tight junctions, and significant increases in MDA content and MPO activity. Rebamipide significantly reduced intestinal permeability, improved inter-cellular tight junctions, and was associated with decreases in intestinal MDA content and MPO activity. At the mitochondrial level, rebamipide increased SDH and ATPase activities, NADH level and decreased mitochondrial swelling.CONCLUSION: Increased intestinal permeability induced by diclofenac can be attenuated by rebamipide, which partially contributed to the protection of mitochondrial function.  相似文献   
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79.
J Clin Hypertens (Greenwich). 2012; 14:637–643. © 2012 Wiley Periodicals, Inc. The authors retrospectively examined data from 3 surveys on hypertension according to the 2010 Chinese Guidelines for the Management of Hypertension. These surveys were conducted in 1991, 1999, and 2007, and included 85,371 individuals 18 years and older who were living in Shandong Province, China. Age‐standardized prevalent hypertension increased from 15.6% in 1991 to 17.3% in 1999 and 32.7% in 2007 (both P<.0001). The ascending prevalence can be partially explained by increasing body weight. Among individuals with hypertension, awareness increased significantly from 27.8% in 1991 to 39.1% in 1999 and 49.2% in 2007. The proportion of pharmacologic treatment also considerably improved, with the estimate of 12.9%, 28.1%, and 43.3% in the 3 surveys, respectively. Hypertension control increased from 3.0% to 4.4% to 7.1% in the past 20 years. The upward trend in blood pressure control was mostly attributable to a rise among men and persons at middle age. This study suggests that the prevalence of hypertension increased in the Shandong population from 1991 to 2007. Although substantially improved, control rates were still unacceptably low. Comprehensive strategies are urgently required to put into practice for the management of hypertension in Shandong Province, China.  相似文献   
80.
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