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63.

Purpose

In mouse models of prostate cancer, increased epinephrine levels accelerated tumor growth via the beta2-adrenoreceptor/PKA signaling pathway. It is unknown, however, whether men experience increased epinephrine levels sufficient to activate the beta2-adrenoreceptor/PKA pathway in the prostate gland. We measured epinephrine levels in blood samples collected immediately prior to prostate biopsies and measured phosphorylation of S133CREB (PKA site), S112BAD, T202/Y204ERK, and S473 Akt in prostate biopsy tissue samples.

Methods

Tissue samples and 3 ml of blood were obtained from men (n = 20) recruited from the patients scheduled for prostate biopsies. Epinephrine levels were measured by ELISA. Proteins were extracted from biopsied tissue, and protein phosphorylation was measured by Western blotting with phospho-specific antibodies. Pearson and Spearman’s rank correlations were analyzed to assess relationships between blood epinephrine levels and phosphorylation of CREB, BAD, AKT, and ERK.

Results

Epinephrine levels above 1 nM were detected in 5 of 20 patients. A strong positive correlation was observed between increased epinephrine levels and CREB phosphorylation. In contrast, no correlation was observed between epinephrine levels and phosphorylation of ERK, BAD, or AKT.

Conclusion

Our results suggest that increased blood epinephrine levels activate the beta2-adrenoreceptor/PKA signaling pathway in human prostate glands. These results will inform future studies to examine whether beta2-selective blockers can inhibit activation of the epinephrine/ADRB2/PKA pathway in prostate tumors of men with increased epinephrine levels and explore the use of beta2-selective blockers as adjuvant therapy for prostate cancer.  相似文献   
64.

Objective

The aim of the present study was to analyze in vitro the combinatorial effects of the antibiotic combination of amoxicillin plus metronidazole on subgingival bacterial isolates.

Design

Aggregatibacter (Actinobacillus) actinomycetemcomitans, Prevotella intermedia/nigrescens, Fusobacterium nucleatum and Eikenella corrodens from our strain collection and subgingival bacteria isolated from patients with periodontitis were tested for their susceptibility to amoxicillin and metronidazole using the Etest. The fractional inhibitory concentration index (FICI), which is commonly used to describe drug interactions, was calculated.

Results

Synergy, i.e. FICI values ≤ 0.5, between amoxicillin and metronidazole was shown for two A. actinomycetemcomitans (FICI: 0.3), two F. nucleatum (FICI: 0.3 and 0.5, respectively) and one E. corrodens (FICI: 0.4) isolates. Indifference, i.e. FIC indices of >0.5 but ≤4, occurred for other isolates and the 14 P. intermedia/nigrescens strains tested. Microorganisms resistant to either amoxicillin or metronidazole were detected in all samples by Etest.

Conclusion

Combinatorial effects occur between amoxicillin and metronidazole on some strains of A. actinomycetemcomitans, F. nucleatum and E. corrodens. Synergy was shown for a few strains only.  相似文献   
65.
目的了解河北省儿童医院住院患儿EB病毒(EBV)感染的流行病学特征,为儿童EBV感染的诊断和预防提供科学依据。方法收集2017年1—12月河北省儿童医院0~14岁EBV感染住院患儿的全血样本,采用酶联免疫吸附试验(ELISA)检测其EBV衣壳抗原(VCA)IgG及IgM抗体,抗早期抗原(EA)IgG抗体和抗核抗原1(NA1)IgG抗体,以检测结果为研究样本的抗体谱。根据4种EBV抗体的检测结果分为现症感染(抗VCA-IgM抗体阳性,抗NA1-IgG抗体阴性、抗VCA-IgG抗体、抗EA-IgG抗体阳性或阴性)、亚急性感染(抗VCA-IgG抗体阳性,抗VCA-IgM抗体、抗NA1-IgG抗体、抗EA-IgG抗体阳性或阴性)、既往感染(抗NA1-IgG抗体阳性,抗VCA-IgG抗体阳性或阴性,其他抗体均为阴性)和未感染(4种抗体均阴性)。按照患儿年龄、检出月份和性别分析各组的阳性率。结果共纳入符合要求的样本4 451例,其中3 257例(73.17%)抗体谱提示EBV感染,包括现症感染380例(8.54%)、亚急性感染616例(13.84%)、既往感染2 261例(50.80%)。不同年龄组原发阳性检出率差异有统计学意义(P<0.05),其中学龄前(>3岁)组的阳性检出率最高(P<0.05);不同检出月份组阳性检出率差异有统计学意义(P<0.05),7月份阳性检出率高于其他月份(P<0.05);男性患儿与女性患儿EBV感染率差异无统计学意义(P>0.05)。380例现症感染患儿的疾病谱以血液系统疾病[传染性单核细胞增多症、急性粒细胞缺乏症、血小板减少性紫癜、EBV相关嗜血细胞综合征]为主,其中传染性单核细胞增多症为临床常见疾病;其次是呼吸系统疾病(急性支气管炎、疱疹性咽峡炎、急性扁桃体炎);其他疾病谱包括神经系统疾病及血流感染、肾病综合征、川崎病。结论河北省儿童医院住院患儿EBV阳性检出率有年龄和检出月份差异,现症感染以血液系统疾病患儿为主,医院应根据流学病学特征制定相应预防措施。  相似文献   
66.
Psoriasis is a chronic inflammatory skin disease. Immunological, genetic, and environmental factors, including diet, play a part in the pathogenesis of psoriasis. Metabolic syndrome or its components are frequent co-morbidities in persons with psoriasis. A change of eating habits can improve the quality of life of patients by relieving skin lesions and by reducing the risk of other diseases. A low-energy diet is recommended for patients with excess body weight. Persons suffering from psoriasis should limit the intake of saturated fatty acids and replace them with polyunsaturated fatty acids from the omega-3 family, which have an anti-inflammatory effect. In diet therapy for persons with psoriasis, the introduction of antioxidants such as vitamin A, vitamin C, vitamin E, carotenoids, flavonoids, and selenium is extremely important. Vitamin D supplementation is also recommended. Some authors suggest that alternative diets have a positive effect on the course of psoriasis. These diets include: a gluten-free diet, a vegetarian diet, and a Mediterranean diet. Diet therapy for patients with psoriasis should also be tailored to pharmacological treatment. For instance, folic acid supplementation is introduced in persons taking methotrexate. The purpose of this paper is to discuss in detail the nutritional recommendations for persons with psoriasis.  相似文献   
67.
BackgroundThis paper is a follow‐up study continuing the COVISTRESS network previous research regarding health‐related determinants.ObjectiveThe aim was to identify the main consequences of COVID‐19 lockdown on Body Mass Index and Perceived Fragility, related to Physical Activity (PA), for different categories of populations, worldwide.DesignThe study design included an online survey, during the first wave of COVID‐19 lockdown, across different world regions.Setting and participantsThe research was carried out on 10 121 participants from 67 countries. The recruitment of participants was achieved using snowball sampling techniques via social networks, with no exclusion criteria other than social media access.Main outcome measures Body Mass Index, Physical Activity, Perceived Fragility and risk of getting infected items were analysed. SPSS software, v20, was used. Significance was set at P < .05.Results Body Mass Index significantly increased during lockdown. For youth and young adults (18‐35 years), PA decreased by 31.25%, for adults (36‐65 years) by 26.05% and for the elderly (over 65 years) by 30.27%. There was a high level of Perceived Fragility and risk of getting infected for female participants and the elderly. Correlations between BMI, Perceived Fragility and PA were identified.Discussion and ConclusionsThe research results extend and confirm evidence that the elderly are more likely to be at risk, by experiencing weight gain, physical inactivity and enhanced Perceived Fragility. As a consequence, populations need to counteract the constraints imposed by the lockdown by being physically active.  相似文献   
68.
流式细胞分析技术(flow cytometry,FCM),又称流式细胞术,是一种在功能水平上对单细胞或其他生物粒子进行定量分析和分选的技术,具有广泛的科研应用价值.采用理论与实践并举,结合讨论的教学方式,在教师队伍开设针对性的培训课程,对深刻理解并在科研工作中有效利用该技术具有及其重要意义.同时以教学促科研,以科研促技...  相似文献   
69.
70.
Lesions of the articular surfaces of the knee have been managed by various techniques over the last 50 years. Surgical management has involved: excising the damaged area, refashioning the underlying bone to produce a fibrous response, and introducing allograft, autograft and synthetic materials to encourage a repair matrix. The techniques and their pitfalls are reviewed and discussed, and suggestions made as to the direction of future studies for the repair of osteochondral lesions in the painful knee.  相似文献   
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