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41.

OBJECTIVE:

To analyze the association between the length of napping during the night shift and the recovery after work among nurses.

METHOD:

Cross-sectional epidemiological study involving 1940 nurses from 18 public hospitals in the City of Rio de Janeiro. A multidimensional and self-applied questionnaire was used with information about health, sociodemographic and occupational characteristics, health-related behaviors and housework. Multiple logistic regression was applied to identify the association, adjusted for confounding variables.

RESULTS:

The gross analyses showed 44%, 127% and 66% higher chances of a high level of recovery after work for nurses who sleep up to two hours, between 2.1 and 3 hours and 3.1 hours or more, respectively, when compared to the nurses who do not sleep. After adjusting for confounding variables, the association only continues significant for the group that sleeps 2.1 to 3 hours during the night shift (OR=1.79; 95%CI=1.33-2.41).

CONCLUSION:

The association between the length of napping and the high level of recovery after work, confirmed in the present results, can be included in the studies that aim to support more appropriate policies aimed at improving the workers'' work, life and health conditions, not only in nursing, but night-shift workers in general.  相似文献   
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Because swine influenza virus infection is seldom diagnosed in humans, its frequency might be underestimated. We report a immunocompromised hematologic patient with swine influenza A(H3N2) virus in 2014 in Italy. Local pigs were the source of this human infection.  相似文献   
44.
Chronic hepatitis C virus (HCV) infection is the principal etiology of cirrhosis and, ultimately, hepatocellular carcinoma (HCC). At present, approximately 71 million people are chronically infected with HCV, and 10%–20% of these are expected to develop severe liver complications throughout their lifetime. Scientific evidence has clearly shown the causal association between miRNAs, HCV infection and HCC. Although it is not completely clear whether miRNA dysregulation in HCC is the cause or the consequence of its development, variations in miRNA patterns have been described in different liver diseases, including HCC. Many studies have analyzed the importance of circulating miRNAs and their effect on cell proliferation and apoptosis. In this Review, we aim to summarize current knowledge on the association between miRNA, HCV and HCC from a diagnostic point of view, and also the potential implications for therapeutic approaches.  相似文献   
45.
BACKGROUND: Chlamydia pneumoniae has been associated with coronary artery disease by both seroepidemiological studies, and by direct detection of the micro-organism in atherosclerotic lesions. This bacteria could play a potential role in the development of acute coronary events. We examined coronary arteries from patients with unstable angina in order to verify an endovascular presence of C. pneumoniae, and to determine if there is any relationship between serology of acute infection by this pathogen and its presence inside the atherosclerotic plaque of these patients. METHODS: We analysed a total of 76 atherosclerotic plaques obtained from 45 patients who underwent coronary artery bypass surgery. In all patients unstable angina was present within the prior 3 weeks. The presence of C. pneumoniae in the plaque was determined by nested polymerase chain reaction (PCR). Antichlamydial immunoglobulin G (IgG), A (IgA) and M (IgM) was examined by microimmunofluorescence and compared to the PCR result. FINDINGS: DNA of C. pneumoniae was detected in 57 (75%) of 76 atherosclerotic lesions. In most cases (74/76: 97%) a positive IgA, IgM or IgG result was seen. Seven (12%) and 54 (94%) of the 57 PCR positive plaques came from patients with a positive IgM and IgA result, respectively. There was no statistical significant difference between PCR positive and PCR negative plaques in patients with a positive or negative serological result. Clinical characteristics were similarly distributed in patients with and without infected lesions. INTERPRETATION: C. pneumoniae organisms are frequently found in the atherosclerotic lesions of patients undergoing coronary surgery for unstable angina. Neither serological results of acute or recent infection by C. pneumoniae nor clinical characteristics are useful in predicting the individual risk of harbouring C. pneumoniae in the coronary lesions of patients with unstable angina.  相似文献   
46.
Summary Studies of59Fe clearance from the plasma are used for obtaining a quantitative measure of erythropoiesis. However, there are many difficulties associated with a good definition and a valid analysis of the plasma59Fe clearance curve. The low plasma activity, plasma iron variation, and traces of haemolysis are factors which make the measurement of the curve difficult. All these problems were examined in the present work. Liquid scintillation counting allows a more accurate assay of plasma59Fe activity than conventional gamma counting. Plasma iron fluctuations may affect tracer kinetics but adjustment of plasma activity for plasma iron variation (expressing59Fe activity per unit mass of iron) does not appear a satisfactory procedure for overcoming this difficulty. The removal of haemoglobin from plasma samples is a necessary procedure to avoid contamination by [59Fe] haemoglobin. Fitting three exponentials to the plasma59Fe clearance curve does not yield satisfactory results in some cases. A better prediction of the clearance curve in most cases can be obtained by means of a more refined mathematical model.The research was supported by C.N.R. Contract No. 78.00513.86 within the Special Project on Biomedical Engineering.  相似文献   
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Ouarhache  Maryem  Marquet  Sandrine  Frade  Amanda Farage  Ferreira  Ariela Mota  Ianni  Barbara  Almeida  Rafael Ribeiro  Nunes  Joao Paulo Silva  Ferreira  Ludmila Rodrigues Pinto  Rigaud  Vagner Oliveira-Carvalho  Cândido  Darlan  Mady  Charles  Zaniratto  Ricardo Costa Fernandes  Buck  Paula  Torres  Magali  Gallardo  Frederic  Andrieux  Pauline  Bydlowsky  Sergio  Levy  Debora  Abel  Laurent  Cardoso  Clareci Silva  Santos-Junior  Omar Ribeiro  Oliveira  Lea Campos  Oliveira  Claudia Di Lorenzo  Nunes  Maria Do Carmo  Cobat  Aurelie  Kalil  Jorge  Ribeiro  Antonio Luiz  Sabino  Ester Cerdeira  Cunha-Neto  Edecio  Chevillard  Christophe 《Journal of clinical immunology》2021,41(5):1048-1063
Abstract

Cardiomyopathies are an important cause of heart failure and sudden cardiac death. Little is known about the role of rare genetic variants in inflammatory cardiomyopathy. Chronic Chagas disease cardiomyopathy (CCC) is an inflammatory cardiomyopathy prevalent in Latin America, developing in 30% of the 6 million patients chronically infected by the protozoan Trypanosoma cruzi, while 60% remain free of heart disease (asymptomatic (ASY)). The cytokine interferon-γ and mitochondrial dysfunction are known to play a major pathogenetic role. Chagas disease provides a unique model to probe for genetic variants involved in inflammatory cardiomyopathy.

Methods

We used whole exome sequencing to study nuclear families containing multiple cases of Chagas disease. We searched for rare pathogenic variants shared by all family members with CCC but absent in infected ASY siblings and in unrelated ASY.

Results

We identified heterozygous, pathogenic variants linked to CCC in all tested families on 22 distinct genes, from which 20 were mitochondrial or inflammation-related – most of the latter involved in proinflammatory cytokine production. Significantly, incubation with IFN-γ on a human cardiomyocyte line treated with an inhibitor of dihydroorotate dehydrogenase brequinar (enzyme showing a loss-of-function variant in one family) markedly reduced mitochondrial membrane potential (ΔψM), indicating mitochondrial dysfunction.

Conclusion

Mitochondrial dysfunction and inflammation may be genetically determined in CCC, driven by rare genetic variants. We hypothesize that CCC-linked genetic variants increase mitochondrial susceptibility to IFN-γ-induced damage in the myocardium, leading to the cardiomyopathy phenotype in Chagas disease. This mechanism may also be operative in other inflammatory cardiomyopathies.

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