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1.
目的 探讨扶正化瘀方含药血清对肝星状细胞(HSC)激活素A(activinA)/smad信号通路活化的影响。方法 20只SD大鼠按照随机数字表法分为对照组及扶正化瘀(Fzhy)-低、中、高剂量含药血清组,每组5只,分别以蒸馏水,0.75、1.5、3.0 g/kg扶正化瘀溶液(扶正化瘀胶囊药物粉末与蒸馏水配制)灌胃1次/d,连续3 d,取血制备空白血清(对照组)和含药血清。以大鼠HSC-T6细胞为研究对象,分别用5%、10%、20%体积分数的各组含药血清培养细胞。CCK-8检测细胞存活率,选取细胞存活率在50%左右的体积分数重新分为对照组及Fzhy-低、中、高剂量组。流式细胞术检测细胞周期及凋亡率、线粒体膜电位变化和活性氧(ROS)水平;实时荧光定量聚合酶链反应检测细胞中activinA、smad3、samd7、核因子(NF)-κB的mRNA水平;蛋白质印迹法检测细胞中activinⅡA受体(ActRⅡA)、smad3、NF-κB p65、胱天蛋白酶(caspase)-3的蛋白水平。结果 各扶正化瘀含药血清组的细胞存活率均低于对照组(P<0.05),选择体积分数为10%的含药血清进行后续实验。对照组和各扶正化瘀方含药血清组细胞周期和凋亡率差异均无统计学意义。对照组及Fzhy-低、中、高剂量组细胞内ROS水平及线粒体膜电位水平降低比例逐次升高(P<0.05)。与对照组比较,Fzhy-中、高剂量组smad3 mRNA表达水平降低,smad7 mRNA升高,Fzhy-低、中、高剂量组NF-κB、activinA mRNA,smad3、NF-κB p65、ActRⅡA蛋白表达水平降低,Fzhy-低剂量组、中剂量组caspase-3蛋白表达水平升高(P<0.05);与Fzhy-低剂量组相比,Fzhy-中、高剂量组smad3 mRNA表达水平降低,Fzhy-中剂量组activinA及smad7 mRNA升高(P<0.05)。结论 扶正化瘀方含药血清可通过影响HSC-T6细胞增殖、参与细胞的氧化应激以及调节细胞activinA/smad信号转导通路来实现抗纤维化作用。  相似文献   
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《Clinical breast cancer》2020,20(1):e89-e98
IntroductionA reliable risk stratification on the basis of tumor biology and host factors of HER2-positive (HER2+) early breast cancer (eBC) patients is needed. The aim of our study was to assess the prognostic role of body mass index (BMI) and hormone receptor (HR) expression in this setting.Patients and MethodsWe retrospectively evaluated 238 women with stage I to III HER2+ breast cancer who completed adjuvant chemotherapy (CHT) and 1 year of treatment with trastuzumab. The end point was 3-year distant disease-free survival (3yDDFS). Survival analysis was evaluated using the Kaplan–Meier method. Multivariate analysis was performed using Cox proportional-hazards model adjusting for HR status, BMI, tumor staging, size, nodal status, and type of adjuvant CHT. Association among categorical variables was assessed using χ2 test.ResultsThe early recurrence rate after 3 years resulted as 4.2% (40% HR+ patients and 60% HR patients). Neither HR status nor BMI alone showed an association with 3yDDFS in multivariate analysis. However, the hazard ratios for patients with HR tumors who had also BMI ≥25 (3yDDFS 86.9%; 95% confidence interval [CI], 75.0%-97.7%) were amplified compared with patients with HR+ tumors and with BMI <25 (3yDDFS 98%; 95% CI, 94.8%-100.0%) and other subgroups (P = .003). This observation was confirmed in multivariate analysis (hazard ratio, 1.79; 95% CI, 1.04-3.07; P = .03).ConclusionOur real-life data highlight a different risk of eBC recurrence after grouping patients according to HR status and BMI. These results might help clinicians to identify correct treatment strategies. Patients who are HR and have BMI ≥25 might benefit from escalation approaches, whereas those who are HR+ and have BMI <25 might be eligible for a shorter duration of adjuvant treatment with anti-HER2 agents.  相似文献   
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目的:探讨miR-17-5p 通过调控乳腺癌转移抑制基因1 相似基因(breast cancer metastasis suppressor 1 like,BRMS1-like 或BRMS1L)表达调控鼻咽癌细胞增殖和侵袭的分子机制。方法:收集2014 年1 月至2017 年12 月间平煤神马医疗集团总医院收治的40 例鼻咽癌患者切除的鼻咽癌组织及其相应的癌旁组织标本,以及鼻咽癌细胞系CNE 2、HONE 1、C666-1 和鼻咽部永生化上皮细胞株NP69,采用qPCR 检测miR-17-5p 在癌组织和癌细胞系中的表达水平。通过StarBase 数据库预测BRMS1L 与miR-17-5p 的靶向关系,采用双荧光素酶报告基因实验进行验证。WB检测转染miR-17-5p 模拟物和抑制物对CNE2 细胞中BRMS1L表达的影响;CCK-8、Transwell 和流式细胞术检测miR-17-5p/BRMS1L分子轴对CNE2 细胞增殖、侵袭、迁移和凋亡的影响。结果:miR-17-5p 在鼻咽癌组织和鼻咽癌细胞系中呈高表达(P<0.05 或P<0.01),下调miR-17-5p 显著抑制CNE2 细胞增殖、侵袭、迁移但促进细胞凋亡(P<0.05 或P<0.01)。miR-17-5p 靶向作用于BRMS1L并下调其表达水平。过表达BRMS1L可显著抑制CNE2 细胞增殖、侵袭、迁移而促进细胞凋亡(均P<0.01);而同时过表达miR-17-5p 和BRMS1L 可逆转上述作用(均P<0.01)。结论:miR-17-5p通过靶向下调BRMS1L的表达,进而促进CNE2 细胞增殖、侵袭和迁移而抑制细胞凋亡。  相似文献   
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The prokinetic effects of 5‐HT4 receptor (5‐HT4R) agonists have been utilized clinically for almost three decades to relieve symptoms of constipation. Surprisingly, the mechanism(s) of action of these compounds is still being debated. Recent studies highlight luminal 5‐HT4Rs as an alternative and effective target for these prokinetic agents. These include the study by Shokrollahi et al (2019, Neurogastroenterol Motil, e13598) published in the current issue of Neurogastroenterology and Motility, who found that activation of mucosal 5‐HT4Rs by intraluminal prucalopride, significantly enhanced propulsive motor patterns in rabbit colon. The authors highlight the idea that development of agonists targeting luminal 5‐HT4Rs in the colonic mucosa might be more effective and safer in achieving prokinetic effects on intestinal motility. The purpose of this mini‐review is to discuss the evidence for luminal 5‐HT4Rs as an emerging target for prokinetic agents in facilitating propulsive motor patterns in the colon.  相似文献   
8.
Insulin, insulin‐like growth factor‐1 (IGF‐1) and essential amino acids activate the mechanistic target of rapamycin complex 1 (mTORC1), the main nutrient‐sensitive kinase. Metformin, through inhibition of mTORC1 may improve acne. A 12‐week, randomized, open‐labeled study evaluated the efficacy and safety of metformin as an adjunct for moderate to severe facial acne. In total, 84 patients received either oral tetracycline 250 mg bd and topical benzoyl peroxide 2.5% with or without metformin 850 mg daily. Evaluations constituted lesion counts, the Cardiff Acne Disability Index (CADI), metabolic parameters and treatment success rate (Investigators Global Assessment score of 0 or 1 or improvement of two grades). Treatment success rates were higher in the metformin group (66.7% vs. 43.2%; p = .04). The mean percentage reduction from baseline in total lesion counts at Week 12 was greater in the metformin group (71.4% vs. 65.3%; p = .278). The CADI scores showed a greater mean reduction in the metformin group (4.82 vs. 4.22; p = .451). Metformin was equally efficacious in improving acne in lean and overweight subjects. Gastrointestinal symptoms were noted in 31.7% of subjects on metformin. This study presents favorable data for metformin as an adjunct for acne treatment. Further randomized placebo‐controlled studies are required.  相似文献   
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Ghrelin is a hormone associated with feeding and energy balance. Not surprisingly, this hormone is secreted in response to acute stressors and it is chronically elevated after exposure to chronic stress in tandem with a number of metabolic changes aimed at attaining homeostatic balance. In the present review, we propose that ghrelin plays a key role in these stress‐induced homeostatic processes. Ghrelin targets the hypothalamus and brain stem nuclei that are part of the sympathetic nervous system to increase appetite and energy expenditure and promote the use of carbohydrates as a source of fuel at the same time as sparing fat. Ghrelin also targets mesolimbic brain regions such as the ventral segmental area and the hippocampus to modulate reward processes, to protect against damage associated with chronic stress, as well as to potentially increase resilience to stress. In all, these data support the notion that ghrelin, similar to corticosterone, is a critical metabolic hormone that is essential for the stress response.  相似文献   
10.
Toll‐like receptors (TLRs) are involved in colorectal cancer (CRC) pathogenesis. However, the significance of serum TLR concentrations in CRC is unknown. We analyzed serum TLR2 and TLR4 concentrations with ELISA in preoperative samples from 118 patients with CRC and 88 matched controls. We also assessed tissue TLR expression with immunohistochemistry and by detecting serum determinants of systemic inflammation. Most participants (>70%) had undetectable serum TLR2. The mean serum TLR4 levels were lower in patients than in controls (1.1 vs 1.8 ng/mL; p = 0.015). Undetectable TLR4 was more common in stage I (39%) than in stages II–IV (11%, p < 0.001). TLR2 or TLR4 expression in tumor cells did not correlate with serum levels, but abundant TLR2 expression in normal colon epithelium was associated with detectable serum TLR2 (p = 0.034). Undetectable serum TLR2 was linked to high modified Glasgow prognostic scores (p = 0.010), high CRP levels (p = 0.013), blood vessel invasion (p = 0.013), and tended to be associated with worse 5‐year survival (p = 0.052). In conclusion, serum TLR2 levels were inversely associated with systemic inflammation in patients with CRC. Moreover, serum TLR2 levels might depend more on normal colorectal mucosa contributions than on tumor tissue contributions. Further studies are required to assess the prognostic value of serum TLR2.  相似文献   
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