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31.
Sibutramine is a serotonin-noradrenaline reuptake inhibitor that is effective for long-term weight reduction and maintenance in obese patients when used as an adjunct to dietary and behavioural measures. Because the inhibition of noradrenaline reuptake may be expected to increase systolic and diastolic blood pressure (SBP and DBP) and pulse rate (PR), a 12-week multi-centre, placebo-controlled, double-blind study was designed to evaluate the efficacy and tolerability of sibutramine for weight loss in obese patients whose hypertension was well controlled (DBP < or = 95 mm Hg) by beta-adrenergic blocking agents (beta-blockers), with or without concomitant thiazide diuretics. Of the 61 patients randomised to sibutramine 20 mg once daily or placebo, 55 patients (90%) completed the study. After 12 weeks, sibutramine-treated patients lost significantly more weight than placebo-treated patients: mean weight reductions were 4.2 kg (4.5%) in the sibutramine group vs 0.3 kg (0.4%) in the placebo group (P<0.001). Greater weight reduction on sibutramine was accompanied by trends for greater mean reductions in serum triglycerides and very low density lipoprotein cholesterol. Sibutramine was well tolerated, and most adverse events were mild or moderate in severity. No sibutramine patient discontinued treatment because of an adverse event. Mean supine and standing DBP and SBP were not statistically significantly different between the sibutramine group and the placebo group at any post-baseline visit during the 12-week trial. At week 12, mean increases from baseline supine SBP and DBP, respectively, were 1.6 and 1.7 mm Hg for the sibutramine group vs increases of 0.4 and 1.3 mm Hg for the placebo group. At week 12, mean increases from baseline standing SBP and DBP, respectively, were 1.5 and 1.8 mm Hg for the sibutramine group vs an increase of 0.3 and a decrease of 0.8 mm Hg for the placebo group (P > 0.05 for treatment comparison). A statistically significant mean increase of 5.6 bpm (+/-8.25, s.d.) in supine PR from a baseline of 62 bpm was reported in sibutramine-treated patients at week 12, whereas placebo-treated patients had a mean supine PR decrease of 2.2 bpm (+/-6.43) (P < 0.001). In summary, sibutramine was well tolerated and effective in weight reduction. The addition of sibutramine did not result in an increase in BP in obese patients whose hypertension was well controlled by a beta-blocker. However, based on the potential for changes in BP and PR, obese patients being treated with sibutramine should be monitored periodically for changes in BP and PR and managed appropriately.  相似文献   
32.

Purpose

Cumulative evidence suggests that moderate red wine consumption protects the cardiovascular system. The effect of cultured cells derived from red grape berry (RGC) on blood pressure (BP) has not been investigated. We therefore studied the antihypertensive effects of oral consumption of RGC in experimental rat model of metabolic-like syndrome and assessed its effect on human umbilical vein endothelial cells (HUVECs).

Methods

Forty male Sprague–Dawley rats were fed for 5 weeks with either a high fructose diet (HFD) (n = 10) or HFD supplemented, during the last 2 weeks, with different doses (200, 400 and 800 mg/kg/day) of RGC suspended in their food (n = 30). BP, plasma triglycerides, insulin and adiponectin levels were measured at the beginning and after 3 and 5 weeks of diet. RGC effect on vasodilatation was evaluated by its ability to affect endothelin-1 (ET-1) production and endothelial nitric oxide synthase (eNOS) expression in HUVECs.

Results

BP, plasma triglycerides, insulin and adiponectin increased significantly in rats fed with a HFD. The increase in BP, plasma triglycerides and insulin was attenuated by RGC supplementation. Incubation of HUVECs with RGC demonstrated a concentration-dependent inhibition of ET-1 secretion and increase in the level of eNOS, signaling a positive effect of RGC on vasodilatation.

Conclusion

In rats with metabolic-like syndrome, RGC decreased BP and improved metabolic parameters. These beneficial effects may be mediated by the cell constituents, highly rich with polyphenols and resveratrol, reside in their natural state.  相似文献   
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34.

Background

Current pneumococcal vaccine campaigns take a broad, primarily age-based approach to immunization targeting, overlooking many clinical and administrative considerations necessary in disease prevention and resource planning for specific patient populations. We aim to demonstrate the utility of a population-specific predictive model for hospital-treated pneumonia to direct effective vaccine targeting.

Methods

Data was extracted for 1,053,435 members of an Israeli HMO, age 50 and older, during the study period 2008–2010. We developed and validated a logistic regression model to predict hospital-treated pneumonia using training and test samples, including a set of standard and population-specific risk factors. The model's predictive value was tested for prospectively identifying cases of pneumonia and invasive pneumococcal disease (IPD), and was compared to the existing international paradigm for patient immunization targeting.

Results

In a multivariate regression, age, co-morbidity burden and previous pneumonia events were most strongly positively associated with hospital-treated pneumonia. The model predicting hospital-treated pneumonia yielded a c-statistic of 0.80. Utilizing the predictive model, the top 17% highest-risk within the study validation population were targeted to detect 54% of those members who were subsequently treated for hospitalized pneumonia in the follow up period. The high-risk population identified through this model included 46% of the follow-up year's IPD cases, and 27% of community-treated pneumonia cases. These outcomes were compared with international guidelines for risk for pneumococcal diseases that accurately identified only 35% of hospitalized pneumonia, 41% of IPD cases and 21% of community-treated pneumonia.

Conclusions

We demonstrate that a customized model for vaccine targeting performs better than international guidelines, and therefore, risk modeling may allow for more precise vaccine targeting and resource allocation than current national and international guidelines. Health care managers and policy-makers may consider the strategic potential of utilizing clinical and administrative databases for creating population-specific risk prediction models to inform vaccination campaigns.  相似文献   
35.
Background.?Proprioception provides feedback which is essential for adequate motor control. Despite having detrimental functional implications, the assessment of proprioception deficits in current clinical practice is mostly qualitative and inadequate for diagnosis and longitudinal monitoring of subtle impairments and their effect on motor function.

Purpose.?To evaluate a novel quantitative approach to the assessment of proprioception deficits in stroke patients.

Method.?We designed and implemented an automated protocol where a magnetic motion tracking system and a sensor attached to each of the patient's hands, enables registration of trajectories in 3D coordinates. In this protocol the patient's affected and healthy hands are placed respectively below and above a square board. With vision blocked, the subject's affected hand is passively moved to one of four locations, and then the patient is instructed to actively position the healthy hand directly above his/her perceived location of the affected hand. The positional difference between the two hands is automatically recorded by the system. This procedure is repeated several times and the magnitude and direction of errors are used to quantify the proprioception deficit. The data for this pilot study was collected in a sample of 22 stroke patients and an age-matched group of neurologically intact subjects.

Results.?Stroke patients had significantly higher mean distance error compared with the control group (average values of 7.9 and 5.3 cm, respectively), and showed higher instability (variance) in repeated performance (average values of the standard deviation of errors 3.4 and 1.8 cm, respectively). Significant correlation was found between the mean distance error and the results of semi-quantitative clinical tests of proprioception.

Conclusion.?The system provides a reliable quantitative measure of upper limb proprioception, offering considerable advantage over the traditional means applied in the clinic.  相似文献   
36.
PURPOSE: To determine if serologic recognition of p53 mutations at the protein level depends upon the ability of mutant p53 to express new peptide epitopes that bind to human leukocyte antigen (HLA) class II molecules, we used anti-p53 antibody production as a marker for HLA class II-restricted T-cell involvement in head and neck cancer. EXPERIMENTAL DESIGN: An anti-p53 antibody response was correlated with specific p53 mutations and the patients' HLA class II alleles and haplotypes. HLA binding studies and in vitro stimulation (IVS) of peripheral blood mononuclear cells were done using a mutant versus wild-type HLA-DQ7-binding p53 peptide. RESULTS: Certain HLA-DQ and HLA-DR alleles were frequently present in p53 seropositive patients who produced serum anti-p53 antibodies. Selected mutated p53 peptides fit published allele-specific HLA class II binding motifs for the HLA-DQ7 or HLA-DR1 molecules. Moreover, a mutant p53 peptide bound with a 10-fold greater affinity than the wild-type p53 peptide to HLA-DQ7 molecules. IVS of CD4(+) T cells from seven healthy HLA-DQ7(+) donors using this mutant p53 peptide (p53(220C)) was associated with a partial T helper type 2 phenotype compared with IVS using the wild-type p53(210-223) peptide. CONCLUSIONS: Our results support the hypothesis that mutated p53 neoantigens can bind to specific HLA class II molecules, leading to a break in tolerance. This may lead to skewing of the CD4(+) T lymphocyte response toward a tumor-permissive T helper type 2 profile in head and neck cancer patients, as manifested by seropositivity for p53.  相似文献   
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The interferon system of 20 children aged 2 to 11 years (mean 5 years), diagnosed as having transient synovitis of the hip by clinical criteria, was studied. The mean blood interferon concentration was significantly higher than that of normal children, and the incidence of an antiviral state of cells (in 78% of patients) was also significantly higher than in the control group. These findings are compatible with the hypothesis that the aetiology of transient synovitis is an acute, possibly unusual, viral infection.  相似文献   
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