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61.
62.

Background

Acute myocardial infarction (AMI) causes irreversible myocardial damage and release of inflammatory mediators, including cytokines, chemokines and miRNAs. We aimed to investigate changes in the levels of cytokines (IL-6, TNF-α and IL-10), miRNAs profiles (miR-146 and miR-155) and distribution of different monocyte subsets (CD14++CD16-, CD14++CD16+, CD14+CD16++) in the acute and post-healing phases of AMI.

Methods

In eighteen consecutive AMI patients (mean age 56.78?±?12.4 years, mean left ventricle ejection fraction – LVEF: 41.9?±?9.8%), treated invasively, monocyte subsets frequencies were evaluated (flow cytometry), cytokine concentrations were analyzed (ELISA) as well as plasma miRNAs were isolated twice – on admission and after 19.2?±?5.9 weeks of follow-up. Measurements were also performed among healthy volunteers.

Results

AMI patients presented significantly decreased frequencies of classical cells in comparison to healthy controls (median 71.22% [IQR: 64.4–79.04] vs. 84.35% [IQR: 81.2–86.7], p?=?0.001) and higher percent of both intermediate and non-classical cells, yet without statistical significance (median 6.54% [IQR: 5.14–16.64] vs. 5.87% [IQR: 4.48–8.6], p?=?0.37 and median 5.99% [IQR: 3.39–11.5] vs. 5.26% [IQR: 3.62–6.2], p?=?0.42, respectively). In AMI patients both, analyzed plasma miRNA concentrations were higher than in healthy subjects (miR-146: median 5.48 [IQR: 2.4–11.27] vs. 1.84 [IQR: 0.87–2.53], p?=?0.003; miR-155: median 25.35 [IQR: 8.17–43.15] vs. 8.4 [IQR: 0.08–16.9], p?=?0.027, respectively), and returned back to the values found in the control group in follow-up. miR-155/miR-146 ratio correlated with the frequencies of classical monocytes (r=0.6, p?=?0.01) and miR-155 correlated positively with the concentration of inflammatory cytokines ? IL-6 and TNF-α.

Conclusions

These results may suggest cooperation of both pro-inflammatory and anti-inflammatory signals in AMI in order to promote appropriate healing of the infarcted myocardium.  相似文献   
63.
64.
We pooled multiethnic data from four population-based studies and examined associations of menstrual and reproductive characteristics with breast cancer (BC) risk by tumor hormone receptor (HR) status [defined by estrogen receptor (ER) and progesterone receptor (PR)]. We estimated odds ratios and 95% confidence intervals using multivariable logistic regression, stratified by age (<50, ≥50 years) and ethnicity, for 5,186 HR+ (ER+ or PR+) cases, 1,365 HR− (ER− and PR−) cases and 7,480 controls. For HR+ BC, later menarche and earlier menopause were associated with lower risk in non-Hispanic whites (NHWs) and Hispanics, and higher parity and longer breast-feeding were associated with lower risk in Hispanics and Asian Americans, and suggestively in NHWs. Positive associations with later first full-term pregnancy (FTP), longer interval between menarche and first FTP and shorter time since last FTP were limited to younger Hispanics and Asian Americans. Except for nulliparity, reproductive characteristics were not associated with risk in African Americans. For HR− BC, lower risk was associated with later menarche, except in African Americans and older Asian Americans and with longer breast-feeding in Hispanics and Asian Americans only. In younger African Americans, HR− BC risk associated with higher parity (≥3 vs. 1 FTP) was increased fourfold in women who never breast-fed, but not in those with a breast-feeding history, suggesting that breast-feeding may mitigate the adverse effect of higher parity in younger African American women. Further work needs to evaluate why menstrual and reproductive risk factors vary in importance according to age and ethnicity.  相似文献   
65.
目的:研究组蛋白去乙酰化酶1(histone deacetylase 1,HDAC1)和细胞周期蛋白依赖性激酶1(cyclin-dependent kinase 1,CDK1)在结肠癌组织中的表达水平及其与患者临床病理特征及预后的关系。方法:收集2012年2月至2013年6月在本院普外科进行手术切除的51例结肠癌患者的肿瘤组织和癌旁非肿瘤组织,采用qRT-PCR法检测组织中HDAC1和CDK1 mRNA相对表达量,采用免疫组织化学染色法检测HDAC1和CDK1蛋白阳性表达率,分析肿瘤组织中HDAC1和CDK1表达的相关性及其与患者肿瘤直径、淋巴结转移等临床病理特征的关系,采用Kaplan-Meier生存函数分析HDAC1和CDK1不同表达情况与患者5年总生存率的关系。结果:肿瘤组织中HDAC1和CDK1 mRNA表达水平和蛋白阳性表达率均高于癌旁非肿瘤组织(P<0.05);肿瘤组织中HDAC1表达水平与CDK1表达水平呈显著正相关(P=0.012);肿瘤组织中HDAC1表达与患者肿瘤直径和组织分化程度有关(P<0.05),CDK1与肿瘤直径、TNM分期、分化程度、淋巴结转移有关(P<0.05);HDAC1、CDK1阳性表达患者5年总生存率均低于其相应阴性表达患者(P<0.05),HDAC1和CDK1共阳性表达患者5年总生存率低于HDAC1和(或)CDK1阴性患者(P<0.05)。结论:HDAC1和CDK1在结肠癌组织中高表达,与患者不良预后有关且两者呈正相关,推测两者在促进结肠癌进展中可能存在协同作用。  相似文献   
66.
目的:观察地黄饮子加减方对血管性痴呆模型大鼠学习记忆能力及海马CA1区神经元的影响。方法:将84只SD雄性大鼠,按随机原则选出12只大鼠作为假手术组,其余72只大鼠采用两血管阻断法制备血管性痴呆模型,筛选60只模型大鼠,每组12只,随机分为模型组,尼莫地平组(0. 011 g·kg~(-1)),地黄饮子加减方高、中、低(4. 54,2. 27,1. 14 g·kg~(-1))剂量组。连续灌胃30 d后,Morris水迷宫检测大鼠学习记忆能力,苏木素-伊红(HE)观察海马CA1区神经元形态结构改变,透射电镜观察海马CA1区神经元超微结构变化,原位细胞凋亡检测法(TUNEL)检测海马CA1区细胞凋亡水平,免疫组化(IHC)检测海马CA1区组织磷脂酰肌醇3-激酶(PI3K),蛋白激酶B(Akt),半胱氨酸蛋白酶-3(Caspase-3)表达水平。结果:与假手术组比较,模型组大鼠逃避潜伏期显著延长,穿越原平台次数显著减少(P 0. 01),海马CA1区神经元形态均有不同程度地损伤,凋亡率显著增加(P 0. 01),PI3K,Akt的积分吸光度和平均积分吸光度明显降低(P 0. 01),Caspase-3的积分吸光度和平均积分吸光度显著增高(P 0. 01);与模型组比较,各给药组大鼠逃避潜伏期缩短(P 0. 05,P 0. 01),穿越原平台次数增加(P 0. 05,P 0. 01),PI3K,Akt的积分吸光度和平均积分吸光度值显著增高(P 0. 01),Caspase-3的积分光密度和平均积分吸光度不同程度降低(P 0. 05,P 0. 01)。结论:地黄饮子加减方可改善血管性痴呆模型大鼠学习记忆能力和海马CA1区神经元损伤,潜在机制可能与PI3K/Akt信号转导途径的激活,抑制大鼠海马CA1区神经细胞的凋亡有关。  相似文献   
67.
BACKGROUND Aloe vera exerts several biological activities, such as, anti-inflammatory, antioxidant, and antimicrobial effects. It was recently shown to reduce insulin resistance and triglyceride level. We hypothesized that aloe vera would have beneficial effects in alleviating non-alcoholic steatohepatitis(NASH) in rats.AIM To examine the therapeutic effects of aloe vera in NASH rats.METHODS All rats were randomly divided into 3 groups(n = 6 in each group). Rats in the control group were fed ad libitum with a standard diet for 8 wk. Rats in the NASH group were fed ad libitum with a high-fat high-fructose diet(HFHFD) for 8 wk. Rats in the aloe vera group were fed ad libitum with a HFHFD and aloe vera in dimethylsulfoxide(50 mg/kg) by gavage daily for 8 wk. Liver samples were collected at the end of the treatment period.RESULTS Hepatic malondialdehyde(MDA) levels increased significantly in the NASH group as compared with the control group(377 ± 77 nmol/mg vs 129 ± 51 nmol/mg protein, respectively, P 0.001). Glutathione(GSH) levels were significantly lower in the NASH group than the control group(9 ± 2 nmol/mg vs 24 ± 8 nmol/mg protein, respectively, P = 0.001). The expression of interleukin-18(IL-18), nuclear factor-kappa β, and caspase-3 increased, while peroxisome proliferator-activated receptor gamma decreased in the NASH group compared with the controls. Following aloe vera administration, MDA levels decreased(199 ± 35 nmol/mg protein) and GSH increased(18 ± 4 nmol/mg protein) markedly. Steatosis, hepatocyte ballooning, lobular inflammation and increased hepatocyte apoptosis were observed in the NASH group. Aloe vera treatment attenuated these changes in liver histology.CONCLUSION Aloe vera attenuated oxidative stress, hepatic inflammation and hepatocyte apoptosis, thus improving liver pathology in rats with NASH.  相似文献   
68.
Cutaneous wound pain causes physical and psychological stress for patients with wounds. Previous studies reported that stress induces hyperalgesia and deteriorates wound healing. However, the effect of the stress response such as in hypothalamic‐pituitary‐adrenal (HPA) axis on local wound area is unclear. We aimed to investigate the effects of a stress response on the mechanical withdrawal threshold in the local wound area and describe the identification of a wound pain exacerbation. We topically injected adrenocorticotropic hormone (ACTH) into the granulation tissue of full‐thickness cutaneous wound model rats on the fifth day postwounding and measured the mechanical withdrawal thresholds, cytochrome P450 2Bs levels and concentration of 5,6‐epoxyeicosatrienoic acid in wound exudate. We found that ACTH induced mechanical hypersensitivity at 4 and 6 hours after injection (P = .004 and .021, respectively), and increased gene expression of cytochrome P450 2B12 expression (P = .046). Concentration of 5,6‐EET in the wound exudate was moderately correlated with the mechanical withdrawal threshold (r = ?.630). Finally, the mechanical withdrawal threshold in the 5,6‐EET group was significantly lower than that in the control group at 2 hours after the injection (P = .015). We propose that 5,6‐EET is one of the most promising contributors to the wound pain exacerbation. These findings could guide clinical wound and pain management.  相似文献   
69.
Schizophrenia is a chronic and severe psychiatric disorder that has profound impact on an individual’s life and on society. Thus, developing more effective therapeutic interventions is essential. Over the past quarter‐century, an abundance of evidence from pharmacologic challenges, post‐mortem studies, brain imaging, and genetic studies supports the role of glutamatergic dysregulation in the pathophysiology of schizophrenia, and the results of recent randomized clinical trials based on this evidence have yielded promising results. In this article, we review the evidence that alterations in glutamatergic neurotransmission, especially focusing on the N‐methyl‐d ‐aspartate receptor (NMDAR) function, may be a critical causative feature of schizophrenia, how this contributes to pathologic circuit function in the brain, and how these insights are revealing whole new avenues for treatment development that could reduce treatment‐resistant symptoms, which account for persistent disability.  相似文献   
70.
Objective: To analyze the effect of sirolimus and sunitinib in blocking the tumor growth and to evaluate the expressions of estrogen receptor (ER), progesterone receptor (PgR), and human epidermal growth factor receptor-2 (HER2/neu) after treated with sirolimus and sunitinib. Methods: Thirty-two female Sprague Dawley rats at age 21-days old were administered intraperitoneally with N-Methyl-N-Nitroso Urea (NMU), dosed at 70mg/kg body weight. The rats were divided into 4 groups; Group 1 (Control, n=8), Group 2 (Sirolimus, n=8), Group 3 (Sunitinib, n=8) and Group 4 (Sirolimus+Sunitinib, n=8), being treated twice when the tumor reached the size of 14.5±0.5 mm and subsequently sacrificed after 5 days. The protein expressions of ER, PgR and HER2/neu of the tumor tissues were evaluated by using immunohistochemistry analysis. Results: Treatment with sirolimus alone lowered expressions of ER and PgR of breast cancer and reduced tumor size. There was no significant difference of ER and PgR expressions between control and sunitinib treated tumor. Sunitinib treated tumors reduce in diameter after the first treatment, however the diameter increases after the second treatment. Histologically, sunitinib treated tumor did not show any aggressive invasive carcinoma of no special type (NST) histological subtypes. In addition, all NMU-induced tumors are HER2/neu-negative scoring. Conclusion: Sirolimus is neither synergistic nor additive with sunitinib for breast cancer treatment.  相似文献   
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