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991.
Increased circulating free fatty acid (FFA) concentrations have been demonstrated to potentially link obesity, insulin resistance and cardiovascular diseases. Astragaloside IV (AS-IV) is a saponin which is widely used in traditional Chinese medicine to treat type 2 diabetes and cardiovascular diseases. The purpose of the present study was to examine the effects of AS-IV on the lipolysis and insulin resistance induced by tumor necrosis factor-alpha (TNFalpha) in cultured 3T3-L1 adipocytes. TNFalpha promotes lipolysis in mammal adipocytes via the mitogen activated protein kinase (MAPK) family resulting in reduced expression/function of perilipin. Application of AS-IV inhibited TNFalpha-induced accelerated lipolysis in a dose-dependent manner, which was compatible with suppressed phosphorylation of ERK1/2 and reversed the downregulation of perilipin. Moreover, TNFalpha induced downregulation of key enzymes in lipogenesis, including LPL, FAS and GPAT, were also attenuated by AS-IV. Further studies showed that AS-IV improved TNFalpha-induced insulin resistance in 3T3-L1 adipocytes. This study provides the first direct evidence of the antilipolytic action of AS-IV in adipocytes, which may allow this agent to decrease the circulating FFA levels, thus increase insulin sensitivity and treat cardiovascular diseases.  相似文献   
992.
In patients with coronary artery disease (CAD), coronary blood flow is usually impaired due to imbalanced vasoactive substances such as nitric oxide (NO) and endothelin-1 (ET-1). The study was designed to test the effects of Ginkgo biloba extract (GBE) on the distal left anterior descending coronary artery (LAD) blood flow and plasma NO and ET-1 levels. Eighty CAD patients were randomly assigned to GBE (n = 42) and control (n = 38) groups. The LAD blood flow was assessed non-invasively using Doppler echocardiography at baseline and after 2 weeks. GBE treatment demonstrated a significant improvement in maximal diastolic peak velocity (MDPV), maximal systolic peak velocity (MSPV) and diastolic time velocity integral (DTVI) compared with controls (14.61 +/- 4.51% vs 0.67 +/- 2.66%, 9.03 +/- 4.81% vs 0.34 +/- 2.67% and 14.69 +/- 5.08% vs 0.68 +/- 3.00%, respectively, p < 0.01). NO was increased by 12.42% (p < 0.01), whereas ET-1 was decreased by 5.82% (p < 0.01). The NO/ET-1 ratio was increased by 19.47% (p < 0.01). A linear correlation was confirmed between the percentage change in LAD blood flow and in NO, ET-1 or NO/ET-1 ratio following GBE treatment. The results suggest that GBE treatment in CAD patients led to an increase of LAD blood flow, which might at least be related partly to the restoration of the delicate equilibrium between NO and ET-1.  相似文献   
993.

Objective

To analyse for the first time the response of the corticotroph-type and the melanotroph-type pituitary proopiomelanocortin (POMC) system with regard to in-vitro fertilisation (IVF) treatment using self-developed highly specific non-cross-reacting radioimmunoassay.

Study design

Setting: University hospital. Patients: A total of 28 patients undergoing IVF oocyte retrieval. Cross sectional exploratory study, one factorial design with repeated measurements on one factor, non-parametric tests. Blood was collected before anaesthesia (tA) (n = 28) and immediately after oocyte retrieval (tB) (n = 28). Main outcome measure(s): β-endorphin immunoreactive material (IRM), acetyl-N-β-endorphin IRM, β-lipotropin IRM, ACTH, cortisol, estradiol, progesterone, prolactin, luteinizing hormone, and follicle-stimulating hormone. For determination of authentic β-endorphin [β-endorphin (1–31)] a highly specific two-site fluid phase immunoprecipitation radioimmunoassay was developed, which did not cross-react with any β-endorphin derivative or any other opioid peptide tested.

Results

No response of acetyl-N-β-endorphin IRM and of authentic β-endorphin (1–31) was observed to oocyte retrieval in contrast to a significant increase of corticotroph-type proopiomelanocortin derivatives. A significant rise in prolactin plasma concentration indicates a pronounced lactotroph response to oocyte retrieval stress. No significant correlation between POMC derivates and prolactin and between POMC derivatives and gonadotropins or sexual steroids except for ACTH and progesterone and for β-endorphin IRM and estradiol was observed.

Conclusion

IVF treatment stress led to significant corticotroph-type POMC and lactotroph responses, but not to responses of authentic β-endorphin or melanotroph-type POMC in women undergoing oocyte retrieval.  相似文献   
994.

Objectives

Gene expression analysis has identified several breast cancer subtypes, including luminal, epidermal growth factor receptor-2 positive (HER2+), and basal-like. To determine if our proposed molecular taxonomy correlates with biological and clinical behavior. This is based on four biological markers: estrogen and progesterone receptors (ER and PR, respectively), HER2 and the epidermal growth factor receptor-1 (HER1), all of them being determined by quantitative assays.

Study design

The biological parameters were examined by enzyme immunoassay, radioligand-binding assay or ELISA, in tumors from 787 patients with invasive breast cancer. Patients were prospectively evaluated over a median follow-up period of 50 months. Subtype definitions were as follows: luminal (ER+), HER2+ (HER2+, ER−, PgR−) and basal-like (HER2−, ER−, PgR−). In addition, we divided basal tumors into two groups based on their HER1 status.

Results

A 55.8% of tumors were of luminal type, 11.9% basal-like HER1+, 10.7 basal-like HER1−, and the remainder 21.6% HER2+. Both HER2+ and basal-like subtypes were more frequent in younger and premenopausal women, showing a higher percentage of cases of poorly differentiated tumors and higher S-phase fraction, when compared with those of luminal subtype. Multivariate analysis demonstrated that the subtype of tumor was related to both relapse and overall survival, being those of luminal subtype associated with the best prognosis.

Conclusions

Through the classification of breast tumors in four groups, according to their ER, PgR, HER2 and HER1 status, it is possible to obtain a major division of breast tumors associated with significant differences in biological features and clinical behavior.  相似文献   
995.
目的 探讨限制性输液复苏法对失血性休克孕兔血流动力学变化及血清肿瘤坏死因子α(TNF-α)、白细胞介素6(IL-6)含量变化的影响.方法 将20只妊娠中晚期新西兰大白兔分为2组,分别采用生理盐水传统输液复苏法(PNL组)及限制性输液复苏法(PLH组),每组10只.建立非控制性失血性休克模型,实验设计分为休克期(0~30 min),院前复苏期(30~90 min)及院内复苏期(90~180 min).休克期:两组孕兔均接受颈动脉放血至平均动脉压(MAP)为40~45 mm Hg(1 mm Hg=0.133 kPa).院前复苏期:剪开两组孕兔孕囊血管放血,复制活动性出血模型,然后PNL组和PLH组孕兔分别接受生理盐水及自身血复苏至MAP为80、60 mm Hg.院内复苏期:两组孕兔均接受手术止血及输血、输液治疗.比较两组孕兔各时间点血流动力学、TNF-α及IL-6含量的变化,记录输血、输液量及生存率.结果 (1)120 min时,PLH组孕兔呼吸、心率分别为(66±16)、(235±41)次,PNL组分别为(78±16)、(291±37)次,两组分别比较,差异有统计学意义(P<0.01);PLH组孕兔MAP和中心静脉压(CVP)分别为(80.4±7.2)mm Hg、(8.0±4.4)cm H2O,PNL组孕兔分别为(72.5±8.2)mm Hg、(5.8±3.1)cm H2O,两组分别比较,差异也有统计学意义(P<0.01);(2)两组孕兔血清TNF-α、IL-6含量休克后均升高,且在240 min时达高峰,PLH组孕兔血清TNF-α、IL-6含量分别为(105±67)、(118±51)ng/L,PNL组分别为(280±160)、(311±240)ng/L,两组比较,差异有统计学意义(P<0.01),且PLH组孕兔血清TNF-α、IL-6含量在480 min时已降至正常;(3)PLH组输血、输液量在院前复苏期分别为(16.0±2.2)、(39.0±5.5)ml,在院内复苏期分别为(28.0±6.7)、(90.0±7.1)ml,PNL组在院前复苏期分别为(31.0±8.2)、(85.0±7.9)ml,在院内复苏期分别为(37.5±9.4)、(140.0±24.8)ml,两组比较,差异也有统计学意义(P<0.05);(4)PLH组孕兔24、72 h的生存率分别为100%、90%;PNL组为80%、60%,两组比较,差异有统计学意义(P<0.01).结论 限制性输液有利于失血性休克孕兔血流动力学指标的恢复,缓解血清TNF-α、IL-6含量升高的程度,从而提高了动物生存率.  相似文献   
996.
Material and methods We analyzed the expression of hypoxia inducible factor-1α (HIF-1α) and glucose transporter-1 (GLUT-1) by immunohistochemistry in ovarian serous and mucinous tumors from the point view of the histological characteristics and acquisition of malignancy. A total of 102 ovarian tumors were examined, composed of 31 adenomas (serous 17 and mucinous 14), 32 borderline tumors (serous 13 and mucinous 19), and 39 adenocarcinomas (serous 21 and mucinous 18). Results The overall positive ratios were as follows: HIF-1α, 74% of adenomas, 91% of borderline tumors, and 100% of adenocarcinomas; and GLUT-1, 68% of adenomas, 95% of borderline tumors, and 100% of adenocarcinomas. Comparing serous tumors and mucinous tumors, there was no significant difference in the positive ratios of HIF-1α and GLUT-1 of adenomas, borderline tumors, and adenocarcinomas. However, both markers were more strongly expressed in serous adenocarcinomas (HIF-1α, 3 + 100%; GLUT-1, 3 + 76%) than in mucinous adenocarcinomas (HIF-1α, 3 + 61%; GLUT-1, 3 + 28%). The results of immunoblotting and mRNA expression level analyses corresponded with those of immunohistochemical expression profiles. DNA binding assay also demonstrated that HIF-1 is more commonly activated in serous adenocarcinomas than in mucinous adenocarcinomas. Conclusion HIF-1α and GLUT-1 expressions seemed to be coordinated to adapt ovarian tumor cells into hypoxic conditions in close association with the acquisition of malignancy. We consider that the relatively strong expression of both markers in serous tumors compared with mucinous tumors is related to the difference in their histological characteristics.  相似文献   
997.
Aim:  Human endometrium is an active site of cytokine production and action. Among these cytokines, the interleukin-1 (IL-1) system seems to be relevant to the embryonic implantation process. We have previously reported the production of GnRH-I by human blastocyst, as well as the presence of GnRH-I receptor in human endometrium. This suggests a close interaction between the immune and endocrine systems through these cytokine mediators in embryonic implantation.
Methods:  To test the relevance of this interaction during embryonic implantation, we investigated GnRH-I regulation of IL-1b and IL-1ra mRNA and protein expression in human endometrial stromal cells using quantitative competitive polymerase chain reaction and ELISA.
Results:  IL-1b mRNA and protein expression in cultured human endometrial stromal cells was significantly enhanced by GnRH-agonist in comparison to control groups. IL-1ra mRNA and protein was significantly decreased by GnRH-agonist in comparison to control groups. In contrast, the GnRH-antagonist ablated the regulatory effects of GnRH agonist in 1b and IL-1ra mRNA and protein levels in a dose-dependent manner.
Conclusions:  In conclusion, these results suggest a possible close interaction between the immune and endocrine systems in human embryonic implantation through the classical neuropeptide hormone GnRH and its receptor.  相似文献   
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