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1.
Results from a randomized clinical trial suggested that vitamin A/beta-carotene supplementation to HIV-1-infected women during pregnancy and lactation may increase the risk of vertical transmission. Limited information is available on the potential role of vitamin A on heterosexual HIV transmission. This is a relevant question in many resource-limited settings where both vitamin A deficiency and HIV infection are highly prevalent. We conducted a case-control study (34 cases and 38 controls) nested within a cohort of HIV-negative women attending family planning clinics in Tanzania, to examine whether low serum concentrations at baseline were associated with the risk of seroconversion. There was not a significant association (OR = 2.14, 95% C I = 0.54, 8.45). In light of these and previous results, we conclude that there is not enough evidence yet to suggest a causal association between vitamin A and heterosexual transmission.  相似文献   
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Allopurinol hypersensitivity syndrome (AHS) is a severe drug reaction. It is characterized by rash, fever, and internal organ involvement. It may present in different clinical forms. We present a case of acute generalized exanthematous pustulosis occurring as a manifestation of AHS.KEY WORDS: Allopurinol, hypersensitivity syndrome, pustulosis  相似文献   
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Background.We compared vaccine coverage achieved by 2 different delivery strategies for the quadrivalent human papillomavirus (HPV) vaccine in Tanzanian schoolgirls. Methods.In a cluster-randomized trial of HPV vaccination conducted in Tanzania, 134 primary schools were randomly assigned to class-based (girls enrolled in primary school grade [class] 6) or age-based (girls born in 1998; 67 schools per arm) vaccine delivery. The primary outcome was coverage by dose. Results.There were 3352 and 2180 eligible girls in schools randomized to class-based and age-based delivery, respectively. HPV vaccine coverage was 84.7% for dose 1, 81.4% for dose 2, and 76.1% for dose 3. For each dose, coverage was higher in class-based schools than in age-based schools (dose 1: 86.4% vs 82.0% [P?=?.30]; dose 2: 83.8% vs 77.8% [P?=?.05]; and dose 3: 78.7% vs 72.1% [P?=?.04]). Vaccine-related adverse events were rare. Reasons for not vaccinating included absenteeism (6.3%) and parent refusal (6.7%). School absenteeism rates prior to vaccination ranged from 8.1% to 23.5%. Conclusions.HPV vaccine can be delivered with high coverage in schools in sub-Saharan Africa. Compared with age-based vaccination, class-based vaccination located more eligible pupils and achieved higher coverage. HPV vaccination did not increase absenteeism rates in selected schools. Innovative strategies will be needed to reach out-of-school girls. Clinical Trials Registration. NCT01173900.  相似文献   
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TLR3 is a key receptor for recognition of double-stranded RNA and initiation of immune responses against viral infections. However, hyperactive responses can have adverse effects, such as virus-induced asthma. Strategies to prevent TLR3-mediated pathology are therefore desired. We investigated the effect of single-stranded DNA oligonucleotides (ssDNA-ODNs) on TLR3 activation. Human monocyte-derived dendritic cells up-regulate maturation markers and secrete proinflammatory cytokines on treatment with the synthetic TLR3 ligand polyinosine-polycytidylic acid (poly I:C). These events were inhibited in cultures with ssDNA-ODNs. Poly I:C activation of nonhematopoietic cells was also inhibited by ssDNA-ODNs. The uptake of poly I:C into cells was reduced in the presence of ssDNA-ODNs, preventing TLR3 engagement from occurring. To confirm this inhibition in vivo, we administered ssDNA-ODNs and poly I:C, alone or in combination, via the intranasal route in cynomolgus macaques. Proinflammatory cytokines were detected in nasal secretions in the poly I:C group, while the levels were reduced in the groups receiving ssDNA-ODNs or both substances. Our results demonstrate that TLR3-triggered immune activation can be modulated by ssDNA-ODNs and provide evidence of dampening proinflammatory cytokine release in the airways of cynomolgus macaques. These findings may open novel perspectives for clinical strategies to prevent or treat inflammatory conditions exacerbated by TLR3 signaling.  相似文献   
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Persistent fifth - double-lumen - aortic arch is a rarely seen entity, which is usually associated with other cardiac anomalies; it has been previously reported only in children. We report a new case of double-lumen aortic arch with a systemic-to-systemic connection diagnosed incidentally during cardiac multi-detector computer tomography evaluation of coronary artery bypass grafts in an adult.  相似文献   
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Patients with acute cardiac symptoms, elevated cardiac troponin and culprit-free angiograms comprise a significant proportion of patients admitted with presumed acute coronary syndromes (ACS). International guidelines recommend that these patients receive lifelong secondary prevention under the presumption that angiographically undetectable coronary artery disease is the likeliest cause for their presentation. Recent studies using cardiac MRI suggest myocarditis to be the most common cause of these presentations. Emerging data also suggest that myocarditis presenting like an ACS may not be benign. In this article the current literature on patients presenting with acute cardiac symptoms, elevated cardiac troponins but culprit-free angiograms is reviewed, focusing on the diagnostic utility of cardiac MRI in this cohort, and the importance of diagnosing acute myocarditis. The development of higher sensitivity troponin assays will undoubtedly lead to an increase in the number of patients with presumed ACS but culprit free angiography. Robust management pathways including cardiac MRI are vital for cardiac centres dealing with these patients in order to achieve cost-effective, individualised patient care.  相似文献   
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Background

Left ventricular (LV) trabeculation is highly variable among individuals and is increased in some diseases (e.g., congenital heart disease or cardiomyopathies), but its significance in population-representative individuals is unknown.

Objectives

The goal of this study was to determine if excessive LV trabeculation in population-representative individuals is associated with preceding changes in cardiac volumes and function.

Methods

For technical reasons, the extent of trabeculation, which is expressed as the ratio of noncompacted to compacted (NC/C) myocardium, was measured on cardiac magnetic resonance (CMR) long-axis cine images in 2,742 participants in the MESA (Multi-Ethnic Study of Atherosclerosis) (mean age 68.7 years; 52.3% women; 56.4% with hypertension; 16.8% with diabetes) at examination 5. These were considered in quintiles of trabeculation extent; the NC/C ratio of quintile 5 was 2.46 to 5.41. We determined the relationship between the maximal NC/C ratio and the preceding change (9.5 years between examinations 1 and 5) in end-systolic volume indexed (ESVi) to body surface area. Secondary analyses assessed the associations between the maximal NC/C ratio and preceding changes in end-diastolic volume indexed (EDVi) to body surface area and the ejection fraction (EF).

Results

Over 9.5 years, the ESVi decreased by 1.3 ml/m2, the EDVi decreased by 5.1 ml/m2, and the EF decreased by 0.6% (p < 0.0001). Even in subjects with excessive trabeculation, there were no clinically relevant differences in LV volumes and systolic function changes among the quintiles of trabeculation extent.

Conclusions

Greater extent of, and even excessive, LV trabeculation measured in end-diastole in asymptomatic population-representative individuals appeared benign and was not associated with deterioration in LV volumes or function during an almost 10-year period.  相似文献   
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