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61.
Emerging mosquito-borne alphavirus infections caused by chikungunya virus (CHIKV) or o'nyong-nyong virus (ONNV) are responsible for sporadic and sometimes explosive urban outbreaks. Currently, there is no licensed vaccine against either virus. We have developed a highly attenuated recombinant CHIKV candidate vaccine (CHIKV/IRES) that in preclinical studies was demonstrated to be safe, immunogenic and efficacious. In this study we investigated the potential of this vaccine to induce cross-protective immunity against the antigenically related ONNV. Our studies demonstrated that a single dose of CHIKV/IRES elicited a strong cross-neutralizing antibody response and conferred protection against ONNV challenge in the A129 mouse model. Moreover, CHIKV/IRES immune A129 dams transferred antibodies to their offspring that were protective, and passively transferred anti-CHIKV/IRES immune serum protected AG129 mice, independently of a functional IFN response. These findings highlight the potential of the CHIKV/IRES vaccine to protect humans against not only CHIKV but also against ONNV-induced disease.  相似文献   
62.
In order to define a dose regimen of teicoplanin for patients undergoing chronic haemodialysis so that they achieved trough drug serum levels above 10 mg/l, two single doses of 5 and 10 mg/kg were administered intravenously in seven anuric patients immediately after the end of haemodialysis. Concentrations of teicoplanin were determined by a microbiological assay in samples collected from peripheral veins via the arterial and the venous lines of the fistulae and from the dialysate during haemodialysis. The administration of a 5 and 10 mg/kg dose gave mean C(max) of 62.80 and 122.43 mg/l, mean AUC of 526.43 and 1103.98 mg h/l, mean half life (t(1/2)) of 109.09 and 107.06 h, mean clearance rates of 12.85 and 12.44 ml/min, mean apparent volumes of distribution of 1.68 and 1.68 l/kg and mean volumes of distribution at steady state of 0.31 and 0.28 l/kg, respectively. Trough serum levels above 10 mg/l were found for 24 h after the administration of the 5 mg/kg dose and for 48 h after the administration of the 10 mg/kg dose. Teicoplanin was not detected in the dialysate. Its concentrations in both the arterial and the venous lines of the fistulae were similar. Based on the time period after the administration of teicoplanin where the desired trough serum levels were found and on the observed t(1/2), it is proposed that teicoplanin should be administered at a dose of 10 mg/kg at 48-72 h intervals, in patients undergoing chronic haemodialysis for the therapy of infections caused by Gram-positive cocci.  相似文献   
63.
The aim of this study was to investigate the association of breakfast consumption with children’s diet quality and cardiometabolic risk factors. Study sample consisted of 1558 children aged 4–8 years from Cyprus. Breakfast frequency was assessed through a parental questionnaire. Body mass index (BMI), BMI z-scores, waist circumference, blood lipid profile and blood pressure were examined in relation to breakfast frequency consumption. Habitual breakfast consumers’ daily nutrient intake was assessed through a 24-Hour Dietary Recall, according to their breakfast choices. Girls who have breakfast on a daily basis had lower mean BMI and BMI z-score; they were also less likely of having abnormal levels of serum triglycerides, atheromatic index (total cholesterol to high density lipoprotein-cholesterol ratio) and diastolic blood pressure after controlling for several confounding factors. Within regular breakfast consumers, of both boys and girls, those having ready to eat cereals had a superior nutrient intake profile. Daily breakfast consumption along with good breakfast choices is an important public health message for Cypriot children.  相似文献   
64.
Arterial stiffness is an independent predictor of cardiovascular (CV) morbidity and mortality in patients with hypertension, as well as a potential therapeutic target. There is increasing awareness that the pulsatile hemodynamics (central blood pressure [CBP], pulse pressure [PP], wave reflections [augmentation index or AIx] and pulse wave velocity [PWV]) may provide better insight into the pathophysiology of CV disorders and target organ damage related to hypertension. Different antihypertensive drugs produce diverse effects on arterial stiffness variables, despite similar effects on peripheral (brachial) blood pressure. Identifying the pharmacologic interventions that can improve arterial stiffness ('de-stiffening' treatment) is a promising field of research.  相似文献   
65.
Thrombosis plays a key role in the pathophysiology of acute coronary syndromes (ACS). The management of patients with ACS includes interventional procedures and use of antithrombotic agents acutely, and dual antiplatelet therapy (aspirin and a P2Y12 receptor antagonist) for secondary prevention. However, patients with recent ACS remain at a substantial residual risk for recurrent ischemic events or death. The idea of follow-up treatment with an oral anticoagulant on top of standard therapy seems promising. Warfarin was the first oral anticoagulant thoroughly investigated in this direction, but the widespread long-term use of warfarin in ACS has been limited by challenges associated with pharmacodynamic/pharmacokinetic deficiencies of the drug and the risk of bleeding. Novel oral anticoagulants, such as direct thrombin inhibitors (DTIs) and FXa inhibitors overcome the downsides of VKAs. Ximelagatran was the first DTI, investigated and proven to be effective in prevention of recurrent ischemic events in ACS patients, but the drug association with hepatotoxicity prompted its withdrawal. Dabigatran etexilate, apixaban, darexaban (YM150) and TAK-442 were studied in phase II dose-escalation trials in order to determine the balance between clinical effectiveness and bleeding risk in daily use with dual antiplatelet therapy, with both positive and negative results. Rivaroxaban is the only agent that completed a phase III trial, showing reduction in recurrent ischemic events rate and death from cardiovascular causes as well as all-cause death. This review summarizes the data from completed and ongoing clinical trials of the new oral anticoagulants in patients with ACS.  相似文献   
66.
Statins, angiotensin-converting enzyme (ACE) inhibitors, and calcium channel blockers (CCBs) have markedly changed the clinical progression of patients with coronary artery disease (CAD). The goal of this paper is to review the rationale and evidence for combining these three drug classes in hypertensive patients with hypercholesterolemia or CAD. Data sources include a literature search for publications on the use of a statin combined with various antihypertensive drugs in patients with hypertension and hypercholesterolemia or stable CAD. Hypercholesterolemia and hypertension constitute major physiological risk factors of ischemic heart disease. Current guidelines recommend a global approach to risk management, using agents that address as many risk factors as possible. Dual combination therapies are an important component of guideline-recommended therapy in hypertension. Our review of the literature indicates that triple therapy with a statin, ACE inhibitor, and CCB is associated with a significant reduction in major cardiovascular events. For example, a post hoc analysis in 1056 patients with stable CAD participating in the EUROPA trial indicated that the addition of perindopril to a CCB and a lipid-lowering agent was associated with a 46 % reduction in the composite of cardiovascular death, myocardial infarction, and resuscitated cardiac arrest (p = 0.023). In addition, single pill formulations are known to result in better adherence to the treatment. Single-pill formulations that combine a statin, an ACE inhibitor, and a CCB appear to offer an effective approach to the management of global cardiovascular risk.  相似文献   
67.
Persistent oxidative stress in the vascular wall may lead to endothelial dysfunction, a pathological process widely implicated in the morbidities observed in a spectrum of cardiovascular disease. The production of reactive oxygen species (ROS) is regulated by various oxidase enzymes and mitochondrial electron transport mechanisms. Nitric oxide (NO) is a key mediator of endothelial function via its effect on endothelium dependent vascular relaxation. Therapeutic interventions aimed to increase NO bioavailability in the vasculature may improve the long term cardiovascular outcome for healthy individuals, high-risk subjects, and patients with advanced atherosclerosis. Current therapeutic strategies focus on enhancing synthesis or lowering oxidative inactivation of NO in human vasculature. Of the available therapeutic agents, angiotensin converting enzyme inhibitors and statins have shown most promise at improving endothelial function and cardiovascular outcome after long term administration. Other therapeutic approaches may also be useful towards improving endothelial dysfunction. These strategies include targeting NO synthesis by modulation of endothelial nitric oxide synthase (eNOS) coupling, such as folates and tetrahydrobiopterin. Evidence for the benefits of gene therapy to improve endothelial function is also emerging. However, the long term direct clinical benefit of these strategies aimed to improve endothelial function still remains unclear.  相似文献   
68.
69.

Objective

To assess whether the global target of halving tuberculosis (TB) mortality between 1990 and 2015 can be achieved and to conduct the first global assessment of the lives saved by the DOTS/Stop TB Strategy of the World Health Organization (WHO).

Methods

Mortality from TB since 1990 was estimated for 213 countries using established methods endorsed by WHO. Mortality trends were estimated separately for people with and without human immunodeficiency virus (HIV) infection in accordance with the International classification of diseases. Lives saved by the DOTS/Stop TB Strategy were estimated with respect to the performance of TB control in 1995, the year that DOTS was introduced.

Findings

TB mortality among HIV-negative (HIV−) people fell from 30 to 20 per 100 000 population (36%) between 1990 and 2009 and could be halved by 2015. The overall decline (when including HIV-positive [HIV+] people, who comprise 12% of all TB cases) was 19%. Between 1995 and 2009, 49 million TB patients were treated under the DOTS/Stop TB Strategy. This saved 4.6–6.3 million lives, including those of 0.23–0.28 million children and 1.4–1.7 million women of childbearing age. A further 1 million lives could be saved annually by 2015.

Conclusion

Improvements in TB care and control since 1995 have greatly reduced TB mortality, saved millions of lives and brought within reach the global target of halving TB deaths by 2015 relative to 1990. Intensified efforts to reduce deaths among HIV+ TB cases are needed, especially in sub-Saharan Africa.  相似文献   
70.
BACKGROUND AND PURPOSE: Nasopharyngeal carcinoma (NPC) represents a seldom malignancy in most developed countries. Nevertheless, NPC receives an endemic form in concrete racial entities. The aims of this study were to detect the presence of Epstein-Barr virus DNA (EBV-DNA) in peripheral blood of NPC patients, to molecularly define human leukocyte antigens (HLA) DRB1*, DQA1* and DQB1* allele frequencies, and, finally, to determine whether the genetic predisposition of an individual to NPC depends on the liability to EBV infection. PATIENTS AND METHODS: A total of 101 patients of Hellenic origin and nationality, with histologically proven NPC, participated in this study. EBV-DNA detection was also applied in 66 patients with EBV-related malignancies (Hodgkin's [HL] and non-Hodgkin's lymphoma [NHL]) and infectious mononucleosis (IM), as well as in 80 healthy EBV-seropositive controls. RESULTS: 81% of the NPC patients, 77.8% with HL, 72.2% with NHL, and 66.7% with IM were EBV-DNA positive, whereas the EBV genome was detected only in 15% of the healthy controls. These differences were statistically significant in all cases. Analysis of HLA class II antigens showed decreased frequency of the DRB1*07 (p = 0.003), DQA1*0103 (p = 0.002), and DQA1*0201 (p = 0.003) alleles among NPC patients. A significant association between the HLA-DR/DQ alleles and the presence of EBV-DNA in peripheral whole blood was not established. CONCLUSION: Circulating EBV-DNA and specific HLA class II alleles may predispose to or protect from NPC. However, the results of this study suggest that the genetic predisposition of an individual to NPC is independent of the liability to EBV infection.  相似文献   
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