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91.
92.
Obesity is considered a worldwide public health problem showing an increased prevalence in developing countries, with urgent need for new and more efficient drugs and therapies. Enalapril, an angiotensin-I converting enzyme inhibitor (ACEi), is classically used in anti-hypertensive therapies, however, earlier publications have shown that this drug could also have significant impact on body weight in rats as well as in humans, besides reducing blood pressure. The effect of this drug in the white adipose tissue has been neglected for long time, even considering that most components of the renin-angiotensin and kallikrein-kinin system are expressed in this tissue. Furthermore, the adipose tissue is considered today as one of the most important sites for endocrine/inflammatory regulation of appetite and energy output and AngII has been linked to the metabolism in this tissue. Therefore, we analyzed the influence of chronic enalapril treatment in normotensive rats at earlier ages, evaluating body weight, energy homeostasis, lipid profile and serum levels of the hormones leptin and insulin, in the presence of a standard or a palatable hyperlipidic diet regimen for one month. Our results show that enalapril treatment is able to reduce body fat on both diets, without alteration in serum lipid profile. Furthermore, animals receiving enalapril showed reduction in food intake, leptin level and energy intake. In summary, these findings show for the first time that the ACEi enalapril reduces body fat in young normotensive rats and highlights a novel target to treat obesity and associated diseases.  相似文献   
93.
There have been publically expressed concerns about the costs and allocation of neonatal and perinatal health care resources in Canada and elsewhere for the past 15 years. This paper reports information from a symposium held during the 1996 Canadian Paediatric Society (CPS) annual meeting sponsored by the CPS Section on Perinatal Medicine. Experts in perinatal epidemiology, health care economics, public policy and finance, and consumer perspectives on the outcomes of neonatal and perinatal intensive care explored the following questions: How should the need for health care resources in the neonatal and perinatal area be objectively determined? When there are competing needs between the maternal-newborn area and other areas, how should these be rationalized? What evidence should be used (or should be available) to support the present use of resources? What evidence should be available (or is needed) to change or introduce new uses of resources? The conclusions indicated that there are no generally accepted methods to determine the allocation of health care resources but that considerations need to include population characteristics, desired outcomes, achievable results, values, ethics, legalities, cost-benefit analyses and political objectives. Information from families and adolescents who required the use of high technology and/or high cost programs will contribute individual, family and societal values that complement cost-efficacy analyses.  相似文献   
94.
B7-1和IL-12基因转染对肝癌细胞免疫原性的影响   总被引:2,自引:1,他引:1  
目的 观察B7-1和IL-12基因表达对人肝癌细胞免疫原性原影响。方法 分别将B7-1和IL-12基因以逆转录病毒介导转染HepG2细胞。阳性克隆细胞与健康人外周血淋巴细胞(PBL)混合培养后,用流式细胞仪检测PBL表面Ⅰ类人白细胞抗原(HLA-Ⅰ)分子表达,以MTT法检测PBL的特异性杀伤活性K562细胞的活性。结果 混合HepG2/B7-1HepG2/IL-12细胞组PBL表面的HLA-Ⅰ分子  相似文献   
95.
Tissue‐engineered heart valves aim to reproduce the biological properties of natural valves with anatomically correct structure and physiological performance. The closest alternative to creating an ideal heart valve substitute is to use decellularized porcine heart valves, due to their anatomy and availability. However, the immunological barrier and the structural maintenance limit the long‐term physiological performance of decellularized porcine heart valves. This study investigated the extracellular matrix (ECM) structure of aortic and pulmonary porcine valves decellularized by a low concentration sodium dodecyl sulfate (SDS)‐based method in order to determine the ECM scaffold (ECMS) conditions related to remodeling potential. To assess the structures of the leaflets and conduits of the heart valves, ECM components and their organization were evaluated by histology, biochemical analysis (BC), scanning electron microscopy, multiphoton microscopy, tensile test, immunofluorescence labeling (IF), and Raman microspectroscopy used to draw a profile of the cell niches. Histology and multiphoton imaging of decellularized aortic and pulmonary leaflets and conduits revealed a collagen and elastin histoarchitecture with rearrangement, loosening fibers, and glycosaminoglycan depletion confirmed by biochemistry quantification. The potential cytotoxicity of SDS residues was eliminated after 10 wash cycles. The mechanical properties of the structure of the valve indicated a functional resistance of decellularized ECM. The IF demonstrated the presence of basement membrane, suggesting a potential structure for host cell attachment. The RM analysis showed evidence of molecular interactions, suggesting conservation of the chemical composition, particularly among the protein molecular structures. The structural analyses performed in the semilunar porcine heart valves demonstrate that decellularized ECMS has structural properties that support physiological performance and potential host tissue integration. In fact, decellularized leaflet scaffolds were prone to cell interaction after human adipose‐derived stromal cell seeding and culturing. Further analysis of biocompatibility, particularly the ECM‐cell interaction, can elucidate the remodeling process, in preserved decellularized heart valve scaffold.  相似文献   
96.

Introduction

The aim of this study was to investigate the effects of pretreatment of gel chlorhexidine (CHX) and ethanol (EtOH) on the bond strength and durability of the adhesion of the fiber post relined with resin composite to the root dentin using a total etch adhesive system.

Methods

Forty bovine incisor roots were divided into four groups after phosphoric acid etching: irrigation with physiologic solution (control), 5 minutes with CHX, 1 minute with EtOH, and 5 minutes with chlorhexidine followed by 1 minute with EtOH. Fiber posts relined with resin composite were cemented with either RelyX ARC (3M ESPE, St Paul, MN) and a total etch adhesive system Scotchbond Multi-Purpose (3M ESPE). Each group was randomly divided into two subgroups: 24 hours of storage and 12 months of storage. All roots were sectioned transversely, and the push-out test was performed. Failure modes were observed, and the bond strength means were analyzed by analysis of variance and the Tukey test (α = 0.05).

Results

CHX irrigation resulted in homogeneous bond strength values at 24 hours and 12 months of storage (P < .05). A significant bond strength decrease was noticed after 12 months of storage when irrigations were performed with physiologic solution and EtOH application only or associated with CHX (P < .05).

Conclusions

The use of CHX pretreatment could preserve the bond strength of the fiber post relined with resin composite to root dentin for 12 months. The use of EtOH and CHX followed by EtOH did not preserve the bond strength of the total etch adhesive system Scotchbond Multi-Purpose.  相似文献   
97.

Objectives

To evaluate the sealing ability of five root canal sealers, including two experimental cements (MBP and MTA-Obtura) using the fluid filtration method.

Material and Methods

Teeth were divided into 5 study groups: G1-AH Plus; G2-Acroseal; G3-Sealapex; G4-MBP; G5-MTA-Obtura; and two controls. Chemical-mechanical preparation was performed with ProFile rotary nickel-titanium instruments 1 mm short of the apical foramen. The sealing ability was evaluated by fluid filtration at 15, 30, and 60 days.

Results

The statistical analysis showed significant difference between the materials at different periods (p<0.05). AH Plus and MBP had similar leakage values at 15 and 60 days, alternating with significant reduction at 30 days, while the other materials showed progressive increase in leakage values. Acroseal and Sealapex presented the best results at 15 days and the worst at 60 days.

Conclusions

All sealers evaluated presented fluid leakage, with AH Plus and MBP showing the best results at the end of the experimental period. Acroseal, Sealapex, and MTA-Obtura presented increase in leakage values at longer observation periods.  相似文献   
98.

Background

Prevalence of men with cardiometabolic risk factors (CMRF) is increasing in Japan. Few studies have comprehensively examined the relation between lifestyles and CMRF.

Methods

We examined the baseline data from 3,498 male workers ages 19 to 69 years who participated in the high-risk and population strategy for occupational health promotion (HIPOP-OHP) study at 12 large-scale companies throughout Japan. The physical activity of each participant was classified according to the International Physical Activity Questionnaire (IPAQ). Dietary intake was surveyed by a semi-quantitative Food Frequency Questionnaire. We defined four CMRF in this study as follows: 1) high blood pressure (BP): systolic BP ≥ 130 mmHg, or diastolic BP ≥ 85 mmHg, or the use of antihypertensive drugs; 2) dyslipidemia: high-density lipoprotein-cholesterol concentration < 40 mg/dl, or triglycerides concentration ≥ 150 mg/dl, or on medication for dyslipidemia; 3) impaired glucose tolerance: fasting blood sugar concentration ≥110 mg/dl; 4) obese: a body mass index ≥ 25 kg/m2.

Results

Those who had 0 to 4 CMRF accounted for 1,597 (45.7%), 1,032 (29.5%), 587 (16.8%), 236 (6.7%), and 44 (1.3%) participants, respectively, in the Poisson distribution. Poisson regression analysis revealed that independent factors that contributed to the number of CMRF were age (b = 0.020, P < 0.01), IPAQ (b = -0.091, P < 0.01), alcohol intake (ml/day) (b = 0.001, P = 0.03), percentage of protein intake (b = 0.059, P = 0.01), and total energy intake (kcal)(b = 0.0001, P < 0.01). Furthermore, alcohol intake and its frequency had differential effects.

Conclusions

Alcohol intake, percent protein and total energy intake were positively associated, whereas drinking frequency and IPAQ were inversely associated, with the number of CMRF.  相似文献   
99.
ObjectiveTo assess serum retinol and levels of carotenoids in children and adolescents with acquired immunodeficiency syndrome (AIDS) and to correlate low serum retinol and carotenoid levels with the presence of lipodystrophy, lipid profile changes, lipid peroxidation, and insulin resistance.MethodsA cross-sectional, controlled observational study was carried out with 30 children and adolescents with AIDS (mean age 9.1 y) receiving antiretroviral therapy (median length of treatment 28.4 mo), including 30 uninfected healthy controls matched for age and gender. Clinical and laboratory assessments were performed to determine nutritional status, presence of lipodystrophy, serum concentrations of retinol, β-carotene, lycopene, lipid profile (high-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triacylglycerols), lipid peroxidation (thiobarbituric acid-reactive substances), glycemia, and serum insulin (homeostasis model assessment for insulin resistance, cutoff point >3). Statistical analysis was done with chi-square test and Student's t test.ResultsLipodystrophy was observed in 53.3% of patients with AIDS, and dyslipidemia was detected in 60% and 23% of subjects with human immunodeficiency virus and control subjects, respectively (P = 0.004). A higher prevalence of retinol deficiency (60% versus 26.7%, P = 0.009) and β-carotene deficiency (23.3% versus 3.3%, P = 0.026) was found in the group with human immunodeficiency virus than in the control group. No correlation was found for low retinol and β-carotene levels, changes in lipid and glucose metabolism, or lipodystrophy in children and adolescents with AIDS.ConclusionDespite the high frequency of dyslipidemia, lipodystrophy, and retinol and β-carotene deficiencies, it was not possible to demonstrate a correlation of these findings with lipid peroxidation and insulin resistance. More studies are needed to investigate the causes of retinol and β-carotene deficiencies in this population and the clinical consequences of these findings.  相似文献   
100.
Cell-free circulating DNA in plasma and serum may serve as a biomarker for malignant tumor detection and follow up in patients with a variety of solid tumors including prostate cancer. In healthy patients, DNA is normally released from an apoptotic source which generates small fragments of cell-free DNA, whereas cancer patients have cell-free circulating DNA that originated from necrosis, autophagy, or mitotic catastrophe. Cell-free circulating DNA levels were measured by a quantitative real-time PCR method with a set of primers targeted to amplify the consensus ALU apoptotic versus necrotic origin. Prostate cancer patients before and 3 months after diagnosis showed cell-free circulating DNA released at apoptotic and non-apoptotic cell death. Interestingly, all patients after 6 months demonstrated DNA released at non-apoptotic cell. The principal source of cell-free circulating DNA is of apoptotic and non-apoptotic cell death. However, during treatment, this feature could change. Therefore, the study of cell-free circulating DNA would be important to follow the evolution of the disease during the treatment.  相似文献   
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