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1.
目的 运用网络药理学方法及分子对接技术探讨黄芪干预腹膜纤维化的可能机制。方法 利用中药系统药理学数据库及分析平台(TCMSP)检索黄芪的主要化学成分及靶点,并补充文献报道相关药理作用的成分作为潜在活性成分。以"peritoneal fibrosis"为关键词分别在OMIM、Genecards获取目前已知的与腹膜纤维化相关的疾病靶点,后取两者的交集靶点;对交集基因通过STRING数据库与Cytoscape 3.7.2软件构建"药物-成分-靶点-疾病"网络及蛋白互作(PPI)网络并筛选核心网络。基于R软件使用Bioconductor生物信息软件对核心靶点进行GO及KEGG富集分析,最终采用AutoDock软件将主要有效成分与核心靶点进行分子对接,得出其结合能力。结果 筛选出20个黄芪活性成分及文献报道有相关药理作用4个, 457药物作用靶点,与674个腹膜纤维化病靶点取交集,得到86个共同靶点。GO功能富集分析提示黄芪拮抗腹膜纤维化主要参与了蛋白激酶B信号转导的调节、细胞对化学的应激反应、炎症反应的调节等通路; KEGG通路富集分析主要涉及调控肿瘤、磷脂酰肌醇-3-羟激酶-蛋白激酶B(PI3K-Akt)、晚期糖基化终末产物/晚期糖基化终末产物受体(AGE-RAGE)、人类巨细胞病毒感染、HIF-1信号通路等;分子对接结果显示关键靶点与活性成分具有较好的结合能力。结论 黄芪治疗腹膜纤维化的分子机制,可能与抑制炎症及氧化应激反应、调节多种信号通路等相关。  相似文献   
2.
目的:探讨姑息性胃切除联合术后化疗评分在腹膜转移的胃癌患者预后评估中的临床意义。方法:回顾性分析2010年1月至2016年12月7年间收治的287例发生腹膜转移的胃癌患者的临床病理资料。通过χ2检验分析评分与患者临床病理因素间的关系。通过Kaplan-Meier法绘制生存曲线,Log-rank检验比较患者生存率的差异;采用Cox比例风险回归模型对患者进行预后分析。结果:与评分中得分为2分和1分的患者相比,得分为0分的患者肿瘤侵润至T4b 期的患者较少[31%(18/58)比50.8%(63/124)、56.2%(59/105),P=0.039]。全组患者的中位生存时间仅为8.7月。对患者进行单因素预后分析结果显示,血清白蛋白浓度(≤40 g/L),腹水,腹膜转移范围较大,肿瘤T分期较晚,评分得分较高的患者预后较差(均P<0.05)。将上述因素纳入Cox多因素分析结果显示:评分[HR(95%CI):1.384(1.165~1.644),P=0.000],血清白蛋白浓度[HR(95%CI):0.759(0.593~0.971),P=0.028],肿瘤T分期[HR(95%CI):1.493(1.216~1.832),P=0.000]是患者预后的独立危险因素。结论:评分对于胃癌伴腹膜转移患者的预后生存评估具有重要的临床意义。  相似文献   
3.
ABSTRACT

Purpose

To investigate the expression of IL-11 and its receptor IL-11Rα and to quantify density of CD163+ M2 macrophages in proliferative diabetic retinopathy (PDR).  相似文献   
4.
In a biological microenvironment, free fatty acids (FFA) as ubiquitous biological molecules might interact with nanoparticles (NPs) and consequently change the toxicological responses. However, whether the chemical structures of FFA could influence their interactions with NPs remain unknown. This study investigated the interactions between ZnO NPs and saturated or unsaturated FFA (complexed to BSA), namely stearic acid (SA, C18:0), oleic acid (OA, C18:1), and α-linolenic acid (ALA, C18:3). It was shown that BSA, SA, OA, and ALA increased the atomic force microscope (AFM) heights as well the polydispersity index (PDI) of ZnO NPs. BSA modestly protected THP-1 macrophages from ZnO NP exposure, whereas OA and ALA led to relatively less cyto-protective effects of BSA. Moreover, only co-exposure to ZnO NPs and SA significantly promoted the release of interleukin-8. BSA, SA, OA, and ALA equally changed intracellular ROS and Zn ions associated with ZnO exposure, but co-exposure to ZnO NPs and OA/ALA particularly activated the expression of endoplasmic reticulum stress-apoptosis genes. In combination, these results showed that FFA could influence the colloidal aspects and toxicological signaling pathway of ZnO NPs, which is dependent on the number of unsaturated bonds of FFA.  相似文献   
5.
6.
Abstract.   Gurbuz A, Karateke A, Kabaca C, Kir G, Cetingoz E. Peritoneal tuberculosis simulating advanced ovarian carcinoma: is clinical impression sufficient to administer neoadjuvant chemotherapy for advanced ovarian cancer? Int J Gynecol Cancer 2006; 16(Suppl. 1): 307–312.
Peritoneal tuberculosis mimics advanced ovarian cancer because of the similarities in clinical signs and symptoms such as ascites, pelvic and abdominal pain and mass, and elevation of serum CA125 level. We have presented four cases of peritoneal tuberculosis that underwent exploratory laparotomy for suspected advanced ovarian cancer during a 3-year period. Definitive diagnosis of tuberculosis was performed at laparotomy in all the cases. The frozen-section analysis seems to be the gold standard in the differential diagnosis. In view of these data, clinical diagnosis of advanced ovarian cancer is not sufficient for administering neoadjuvant chemotherapy. Cytologic or pathologic findings must be consistent with ovarian cancer for candidates who are being considered for neoadjuvant chemotherapy.  相似文献   
7.
Arsenic pollution has become increasingly severe. It occurs as the result of geological processes and different human activities. Arsenic toxicity at the respiratory level occurs mainly by inhalation of products of coal combustion. The aim of this study was to evaluate sodium arsenite (As3+) toxicity in murine alveolar macrophages (AMs) in vitro and its association with the alterations in cell metabolism.

No changes in viability, apoptosis or cell area were detected in AMs treated with As3+ concentrations up to 2 μM for 24–96 h. A marked decrease in these end-points was observed for As3+ concentrations ranging from 2.5 μM to 10 μM.

Regarding the dynamics of the endo-exocytic process triggered by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cell incorporation, no variations were detected for As3+ concentrations lower than 2 μM while higher concentrations markedly modified this response.

MTT specific activity, as a measure of cell metabolic activity, was not modified irrespective of the As3+ concentration assayed. However, nitroblue tetrazolium (NBT) specific activity, as a measure of superoxide anion generation, is responsive but only to low As3+ doses.

Although this study focuses on lung macrophages, the effects of As3+ described herein may also apply to the response of macrophages residing in other organs.

Arsenite modifies the metabolic and the oxidative status of AMs in vitro. When macrophages are in an As3+ rich medium, they exhibit a reduction in respiratory burst levels and lose their intrinsic capacity to respond to toxicants.  相似文献   

8.
Ganoderma sinensis has been used widely in Oriental countries for the prevention and treatment of various diseases including cancer. Previous studies have shown that the lipid extract from Ganoderma exhibits direct cytotoxicity against tumor cells. Here, it is reported that the lipid extract from germinating G. sinensis spores, at lower concentrations that have no direct tumoricidal activity, induce potent antitumor immune responses in human monocytes/macrophages. Upon stimulation with the lipid extract, monocytes/macrophages exhibited markedly increased production of proinflammatory cytokines and surface expression of costimulatory molecules. Conditioned medium from stimulated cells effectively suppressed the growth of tumor cells. Apparently, the lipid extract triggered macrophage activation via a mechanism different from that associated with LPS. Moreover, it was observed that the lipid extract could partially re‐establish the antitumor activity of the immunosuppressive tumor‐associated macrophages. These results indicated that in addition to its direct tumoricidal activity, the lipid extract from G. sinensis spores could exert antitumor activity by stimulating the activation of human monocytes/macrophages. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
9.
BACKGROUND: Dialysis patient mortality remains high, and this high mortality may be due to many factors. In peritoneal dialysis (PD) patients, old age, co-morbid diseases, malnutrition, low residual renal function (RRF) and a high peritoneal transport rate have been shown to influence survival, but the relative importance of these factors may differ between different patient populations. Besides, centre practice patterns may differ between centres and may influence patient survival. In addition, the literature suggests that dialysis patient survival may be better in Asian than in Caucasian patients. METHODS: The influence of centre and patient characteristics on patient survival was investigated in 132 Korean and 106 Swedish incident PD patients, who underwent initial biochemical measurements and assessment of adequacy of dialysis, nutritional status, RRF and peritoneal transport characteristics. RESULTS: At the start of PD, Korean patients had a higher prevalence of diabetes, peritoneal Kt/V(urea), peritoneal creatinine clearance and peritoneal fluid removal, and lower body mass index, RRF and dialysate to plasma creatinine concentration ratio (D/P Cr) compared with Swedish patients. Significantly more patients from Korea were placed on temporary haemodialysis before PD (100 out of 132) when compared with Swedish patients (21 out of 106). During the follow-up, there was a significantly higher rate of transfer to other units in Korea and a significantly higher rate of kidney transplantation in Sweden. On Kaplan-Meier analysis, overall patient survival did not differ and relative risk for death was also not different between the two centres even after adjustment for age, diabetes, cardiovascular disease, RRF and D/P Cr. On Cox proportional hazards multivariate analysis, age, diabetes, RRF and D/P Cr were found to be independent predictors of mortality in the combined cohort of patients. While age, diabetes and D/P Cr were independent predictors of mortality in Korean patients, age and RRF independently predicted mortality in Swedish patients. CONCLUSION: Although there were significant differences in centre and patient characteristics, we were unable to confirm a survival advantage for Korean over Swedish PD patients. The results of this study suggest that the reported difference in survival between Asian and Caucasian dialysis patients may have been due, in part, to differences in centre and patient characteristics rather than to race as such. The genetic influence on patient characteristics remains, however, to be elucidated.  相似文献   
10.
目的:探讨腹腔内注射沙培林增强人腹腔抗癌免疫功能的机制。方法:72例早中期胃肠道肿瘤患者术前48h和24h腹腔内分别注射生理盐水和5KE的沙培林,术中采集腹腔内巨噬细胞,计数并测定乳酸脱氢酶(LDH)和酸性磷酸酶(ACP)的活性,巨噬细胞吞噬活力,一氧化氮(NO)的分泌以及对人胃癌MKN1细胞的细胞毒性进行分析。同时采集大网膜,对大网膜乳斑的数量和面积进行观察。结果:沙培林显著增加腹腔巨噬细胞(PMΦ)的数量和NO的分泌,增强LDH和ACP的活性,吞噬活力,以及抗癌细胞毒性,也显著增加了大网膜乳斑的数量和面积。结论:腹腔内注射沙培林可显著增加人大网膜乳斑的数量和面积,并因此增加PMΦ的数量,增强PMΦ的活性。因而增强了腹腔巨噬细胞的免疫功能。  相似文献   
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