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Background

Beta-thalassaemia major (b-TM) has been defined as a combination of chronic hemolytic anemia, iron storage disease and myocarditis, and it has been associated with premature death especially due to heart failure. To the best of our knowledge the status of blood lipids in these patients has rarely been investigated. Thus, we assessed the levels of lipids and lipoproteins in a sample of cardiovascular disease free adult men and women with b-TM.

Methods

During 2003 we enrolled 192 consecutive patients with b-TM that visited our Institution for routine examinations. The Institution is considered the major reference center for b-TM in Greece. Of the 192 patients, 88 were men (25 ± 6 years old) and 104 women (26 ± 6 years old). Fasting blood lipid levels were measured in all participants.

Results

Data analysis revealed that 4% of men and 2% of women had total serum cholesterol levels > 200 mg/dl, and 11% of men and 17% of women had triglyceride levels > 150 mg/dl. In addition, mean HDL cholesterol levels were 32 ± 11 mg/dl in men and 38 ± 10 mg/dl in women, lipoprotein-a levels were 8.3 ± 9 mg/dl in men and 8.8 ± 9 mg/dl in women, apolipoprotein-A1 levels were 111 ± 17 mg/dl in men and 123 ± 29 mg/dl in women, and apolipoprotein-B levels were 60 ± 20 mg/dl in men and 59 ± 14 mg/dl in women. Total-to-HDL cholesterol ratios were 3.7 ± 1.2 and 3.8 ± 1.5 in men and women, respectively.

Conclusions

The majority of the patients had blood lipid levels (by the exception of HDL-cholesterol) within the normal range, and consequently the prevalence of lipid and lipoprotein abnormalities was much lower as compared to the general population of the same age. Interestingly, is that the total – to HDL cholesterol ratio was high in our patients, and may underline the importance of this index for the prognosis of future cardiac events in these patients.
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Context: It has been indicated that acute active and passive tobacco cigarette smoking may cause changes on redox status balance that may result in significant pathologies. However, no study has evaluated the effects of active and passive e-cigarette smoking on redox status of consumers.

Objective: To examine the acute effects of active and passive e-cigarette and tobacco cigarette smoking on selected redox status markers.

Methods: Using a randomized single-blind crossover design, 30 participants (15 smokers and 15 nonsmokers) were exposed to three different experimental conditions. Smokers underwent a control session, an active tobacco cigarette smoking session (smoked 2 cigarettes within 30-min) and an active e-cigarette smoking session (smoked a pre-determined number of puffs within 30-min using a liquid with 11?ng/ml nicotine). Similarly, nonsmokers underwent a control session, a passive tobacco cigarette smoking session (exposure of 1?h to 23?±?1?ppm of CO in a 60?m3 environmental chamber) and a passive e-cigarette smoking session (exposure of 1?h to air enriched with pre- determined number of puffs in a 60?m3 environmental chamber). Total antioxidant capacity (TAC), catalase activity (CAT) and reduced glutathione (GSH) were assessed in participants’ blood prior to, immediately after, and 1-h post-exposure.

Results: TAC, CAT and GSH remained similar to baseline levels immediately after and 1-h-post exposure (p?>?0.05) in all trials.

Conclusions: Tobacco and e-cigarette smoking exposure do not acutely alter the response of the antioxidant system, neither under active nor passive smoking conditions. Overall, there is not distinction between tobacco and e-cigarette active and passive smoking effects on specific redox status indices.  相似文献   
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Asymmetric dimethylarginine (ADMA) is a robust marker of endothelial dysfunction in patients with essential hypertension. We investigated ADMA levels and their association with vascular damage in untreated hypertension. We enrolled consecutive patients with untreated, recently diagnosed hypertension and age‐matched normotensive individuals. 24‐hour blood pressure, central hemodynamics, and arterial stiffness were recorded. A total of 311 individuals were studied: 165 with essential hypertension, 50 with masked hypertension, 25 with white‐coat hypertension, and 71 normotensive individuals. ADMA levels significantly correlated with aortic augmentation index (AIx75) (r = .156, P = .006), aortic pulse pressure (r = .153, P = .007) and marginally with carotid‐femoral pulse wave velocity (r = .110, P = .051), as well as with diastolic office BP. In the multivariate model, aortic AIx75 and age were the only statistically significant predictors of ADMA. This is the largest study to document an independent association between ADMA and aortic AIx75 but not with other indices of arterial stiffness.  相似文献   
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In response to concern about lengthy waiting times for cancer treatment in the UK, the Department of Health introduced 'the colorectal cancer target referral scheme' to improve the referral process for suspected cancer. A user-centred web-based intranet software was developed reflecting the core work of the multi-disciplinary cancer team and the patient journey. The method used was primarily based on the concept of involving the end users (clinicians, nurses, administration staff) in the process of problem definition, software design, formative evaluation, development and implementation, from the very beginning, to ensure its relevance, functionality, and effectiveness. This software improved the interdisciplinary communication among doctors. All patients met the government waiting targets and proved to be a facilitative tool for audit, research and further prospective assessment of our service. Implementing a functional software design is mandatory for the management of target referral patients.  相似文献   
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Introduction

Heart failure (HF) is a major public health problem associated with high rates of morbidity and mortality. Patients with HF exhibit a high prevalence of sleep-disordered breathing (SDB). We have investigated the long-term impact of positive airway pressure (PAP) therapy on heart function and clinical outcomes in patients with advanced HF and concomitant SDB.

Materials and methods

We assessed 18 patients with advanced HF (New York Heart Association (NYHA) functional classification III?CIV) and concomitant SDB (diagnosed with polysomnography) either of obstructive or central type. Eleven patients who received PAP therapy (auto-titrating PAP or adaptive servo-ventilation) for 12 months were compared with seven patients who refused this therapy. All participants were assessed at both baseline and end of follow-up for NYHA functional status, left and right ventricular function, neurohormonal activation, and exercise tolerance. The rates of hospitalization, deaths, and the combination of both were also recorded.

Results

Patients treated with PAP achieved better functional status, higher left ventricular ejection fraction, improved longitudinal right ventricular contractile function, lower levels of b-type natriuretic peptide, and greater exercise performance compared to those who remained untreated. PAP-treated group had a significantly lower incidence of the prespecified combined end-point (i.e., hospital admissions and death) than the control group (87.5 vs. 18.2%, p?=?0.013). Interestingly, the mortality rate was 28% (two out of seven patients) in the control group, while no deaths were recorded in the PAP-treated group.

Discussion

In this preliminary study, we found that treatment of SDB, irrespective of type, in stable patients with advanced HF receiving optimal medical therapy was associated with improvement in cardiac functional status, ventricular contraction, physical performance, and neurohormonal status, leading to better clinical outcomes.  相似文献   
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