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目的 观察半夏泻心汤对饮用葡聚糖硫酸钠(DSS)诱导建立的溃疡性结肠炎(UC)模型小鼠Th17/Treg细胞平衡及肠道微生态的影响,从免疫失衡及菌群紊乱角度分析半夏泻心汤治疗UC的作用机制。方法 将40只C57BL/6J雄性小鼠随机分为空白组、模型组、阳性药(美沙拉嗪)组及半夏泻心汤组,除空白组外的各小鼠采用2.5% DSS水溶液自由饮用7天诱导建立UC小鼠模型。自实验第8日起,分别采用灭菌水、美沙拉嗪水溶液、半夏泻心汤水溶液给上述各组别小鼠灌胃。采用HE染色观察结肠组织病理学变化,ELISA方法检测组织炎症因子含量,流式细胞术检测Th17及Treg细胞的相对数量,16S rRNA测序技术进一步检测模型小鼠粪便中菌群的变化。结果 与空白组比较,模型组小鼠结肠损伤严重,血清炎症因子含量显著升高(P<0.01);与模型组比较,中药干预组小鼠结肠损伤减轻,血清TNF-α、IFN-γ含量显著下降(P<0.05)。较空白组小鼠相比,模型组小鼠Th17细胞百分比显著升高(P<0.01),而Treg细胞百分比显著降低(P<0.01)。经半夏泻心汤干预后,其小鼠Th17细胞数量均显著降低(P<0.05),Treg细胞数量则显著升高(P<0.05)。同时,半夏泻心汤可升高门水平上Firmicutes、属水平上Lachnospiraceae_NK4A136_group、unclassified_f_Lachnospiraceae、Prevotellaceae_UCG-001、Alistipes;降低门水平上Actinobacteriota,科水平上Bifidobacteriaceae、Atopobiaceae、Clostridiaceae,属水平上Clostridium_sensu_stricto_1、Coriobacteriaceae_UCG-002、Bifidobacterium的相对丰度。结论 半夏泻心汤可使Treg细胞相对数量升高、Th17细胞相对数量降低,以维持Th17/Treg细胞动态平衡;同时可降低有害菌Clostridium_sensu_stricto_1、Coriobacteriaceae_UCG-002的相对丰度,升高产短链脂肪酸类菌Lachnospiraceae_NK4A136_group、Prevotellaceae_UCG-001、unclassified_f_Lachnospiraceae等菌属的相对丰度,调控肠道微生物结构及动态平衡,从而发挥治疗UC的作用。  相似文献   
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We aimed to explore the correlation between P27 expression and Helicobacter pylori (H. pylori) infection in gastric cancer, so as to provide evidence for understanding the pathogenesis of gastric cancer caused by H. pylori infection. A total of 82 samples of gastric cancer tissues and 56 samples of tumor-adjacent normal tissues collected from the gastrectomy were enrolled in this study. Then, 14C-urease breathing test was carried out to evaluate the infection of H. pylori in gastric cancer tissues, the expression of P27 in the tissue samples was detected by the immunohistochemistry staining, and the correlation between the H. pylori infection and P27 expression in gastric cancer was analyzed. Of 82 gastric cancer patients, there were 53 patients with H. pylori infection (64.63%). Among the patients with highly or moderately differentiated gastric cancer, the expression of P27 was much higher than that of patients with poorly differentiated gastric cancer (p < 0.01). Besides, comparison of the P27 expression between males and females, among different age groups, tumor sizes, TNM stages, tumor infiltration degrees, or lymph node metastasis, showed no significant differences (p > 0.05). Analysis of the correlation revealed that P27 expression was negatively correlated with the infection of H. pylori (p < 0.01). Multifactorial logistics regression analysis indicated that tumor differentiation was a risk factor of P27-positive expression in gastric cancer tissues (p < 0.01). In addition, P27 expression in the gastric cancer tissues was lower than that in the tumor-adjacent normal tissues (p < 0.01). In gastric cancer patients, expression of P27 is correlated with H. pylori infection which, via downregulating P27, can cause the cancerization of gastric mucosa, and P27, for its role in the development and progression of gastric cancer, is a potential auxiliary indicator for clinical diagnosis whether gastric cancer is complicated with H. pylori infection. So, P27 is a key indicator for diagnosis, treatment, and prognostic evaluation of disease in the advanced stage.  相似文献   
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Background

Advanced low-grade ovarian carcinoma (LGOC) is difficult to treat. In several studies, high estrogen receptor (ER) protein expression was observed in patients with LGOC, which suggests that antihormonal therapy (AHT) is a treatment option. However, only a subgroup of patients respond to AHT, and this response cannot be adequately predicted by currently used immunohistochemistry (IHC). A possible explanation is that IHC only takes the ligand, but not the activity, of the whole signal transduction pathway (STP) into account. Therefore, in this study, the authors assessed whether functional STP activity can be an alternative tool to predict response to AHT in LGOC.

Methods

Tumor tissue samples were obtained from patients with primary or recurrent LGOC who subsequently received AHT. Histoscores of ER and progesterone receptor (PR) were determined. In addition, STP activity of the ER STP and of six other STPs known to play a role in ovarian cancer was assessed and compared with the STP activity of healthy postmenopausal fallopian tube epithelium.

Results

Patients who had normal ER STP activity had a progression-free survival (PFS) of 16.1 months. This was significantly shorter in patients who had low and very high ER STP activity, with a median PFS of 6.0 and 2.1 months, respectively (p < .001). Unlike ER histoscores, PR histoscores were strongly correlated to the ER STP activity and thus to PFS.

Conclusions

Aberrant low and very high functional ER STP activity and low PR histoscores in patients with LGOC indicate decreased response to AHT. ER IHC is not representative of functional ER STP activity and is not related to PFS.  相似文献   
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Journal of Thrombosis and Thrombolysis - The ongoing controversy regarding optimal reversal agent for factor Xa-inhibitors is mainly due to lack of comparative data of andexanet alfa (AA) to...  相似文献   
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