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1.
The aim of this study was to examine hormonal and metabolic changes in a group of 18 professional male cyclists ((.)VO(2)max 69.9 [95 % CI 64.9 to 74.9] mL x kg(-1) x min(-1) ) during two successive periods of adapted intensive training. The second training period included 4 days of cycling competition. Intensity was increased while volume was decreased in the second training. Anthropometric data were collected before and at the end of the two training periods. Venous blood samples were taken in a basal state before the two training sessions and after each training session. Serum concentrations of cortisol (C), testosterone (T), dehydroepiandrosterone sulfate (DHEAs), and catecholamines were determined as well as branched-chain amino acids (valine, leucine, isoleucine) (BCAA) and free fatty acids (FFAs). At the end of the two training periods, the subjects lost fat mass whereas mean body mass was unchanged. The T/C ratio was reduced transiently after the first training session (45.90 %), while DHEAs/C remained unchanged. T/C and DHEAs/C were significantly increased after the second training session compared to the first (48.40 and 97.18 %, respectively). Catecholamines and FFAs were unchanged. The significant increase in BCAA levels after the second training session was of note as it might constitute a "store shape" of amino acids in anticipation of future intense training loads. Based on the responses of testosterone, DHEAs, and cortisol, and on the training-induced increase in BCAA, there appeared to be hormonal and metabolic adaptation despite the inherent psychological stress of competition.  相似文献   
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In Rwanda, frequent mutations in the pfdhfr and pfdhps genes of Plasmodium falciparum have suggested intense sulfadoxine-pyrimethamine resistance. However, data on pfmdr1 are not available but might be important in the context of the first-line treatment with artemether-lumefantrine. During a survey among 749 children under five years of age in southern highland Rwanda, 104 P. falciparum isolates were obtained. Parasite polymorphisms associated with drug sensitivity were typed including the genes pfdhfr, pfdhps, pfmdr1, and pfcrt. Plasma concentrations of chloroquine and pyrimethamine were measured by ELISA. Treatment with artemether-lumefantrine within the preceding two weeks was stated by 12.5% of the respondents; chloroquine in plasma was detected in 17.6%, pyrimethamine in none. Isolates with pfdhfr triple and pfdhps double/triple mutations occurred in 75% and 93%, respectively; 69% of the isolates comprised pfdhfr/pfdhps quintuple or sextuple mutations associated with high-grade sulfadoxine-pyrimethamine resistance. Pfdhfr L164 was absent. The pfmdr1 pattern revealed more than 50% of the F184 polymorphism and almost 40% of the N86-F184-D1246 allele combination known to be selected in infections reappearing following artemether-lumefantrine treatment. Molecular markers demonstrate intense antifolate drug resistance of P. falciparum in southern Rwanda. The present, first-time data on pfmdr1 alleles from Rwanda reveal a pattern which might reflect a predominance of wild types for some alleles or, alternatively, substantial artemether-lumefantrine pressure on the local parasite population.  相似文献   
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A low intake of fruit and vegetables and a high intake of meat are associated with higher cardiometabolic disease risk; however much prior research has relied on subjective methods for dietary assessment and focused on Western populations. We aimed to investigate the association of blood folate as an objective marker of fruit and vegetable intake and holotranscobalamin (holoTC) as a marker of animal-sourced food intake with cardiometabolic risk factors. We conducted a population-based cross-sectional study on 578 adults (mean ± SD age = 38.2 ± 8.6 years; 64% women). The primary outcome was a continuous metabolic syndrome score. The median serum folate was 12.9 (IQR: 8.6–20.5) nmol/L and the mean holoTC was 75 (SD: 34.3) pmol/L. Rural residents demonstrated higher serum folate concentrations (15.9 (9.8–25.9) nmol/L) than urban residents (11.3 (7.9–15.8) nmol/L), but lower holoTC concentrations (rural: 69.8 (32.9) pmol/L; urban: 79.8 (34.9)) pmol/L, p < 0.001 for both comparisons. There was an inverse association between serum folate and metabolic syndrome score by −0.20 in the z-score (95% CI, −0.38 to −0.02) per 10.8 (1 SD) of folate) in a model adjusted for socio-demographic factors, smoking status, alcohol intake, BMI, and physical activity. HoloTC was positively associated with the metabolic syndrome score in unadjusted analysis (0.33 (95% CI, 0.10 to 0.56)) but became non-significant (0.17 (−0.05 to 0.39)) after adjusting for socio-demographic and behavioural characteristics. In conclusion, serum folate and holoTC were associated with the metabolic syndrome score in opposite directions. The positive association between serum holoTC and the metabolic syndrome score was partly dependent on sociodemographic characteristics. These findings suggest that, based on these biomarkers reflecting dietary intakes, public health approaches promoting a higher intake of fruit and vegetables may lower cardiometabolic risk factors in this population.  相似文献   
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The ecology of ebolaviruses is still poorly understood and the role of bats in outbreaks needs to be further clarified. Straw-colored fruit bats (Eidolon helvum) are the most common fruit bats in Africa and antibodies to ebolaviruses have been documented in this species. Between December 2018 and November 2019, samples were collected at approximately monthly intervals in roosting and feeding sites from 820 bats from an Eidolon helvum colony. Dried blood spots (DBS) were tested for antibodies to Zaire, Sudan, and Bundibugyo ebolaviruses. The proportion of samples reactive with GP antigens increased significantly with age from 0–9/220 (0–4.1%) in juveniles to 26–158/225 (11.6–70.2%) in immature adults and 10–225/372 (2.7–60.5%) in adult bats. Antibody responses were lower in lactating females. Viral RNA was not detected in 456 swab samples collected from 152 juvenile and 214 immature adult bats. Overall, our study shows that antibody levels increase in young bats suggesting that seroconversion to Ebola or related viruses occurs in older juvenile and immature adult bats. Multiple year monitoring would be needed to confirm this trend. Knowledge of the periods of the year with the highest risk of Ebolavirus circulation can guide the implementation of strategies to mitigate spill-over events.  相似文献   
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We present an 11-year-old girl with acute myelogenous leukemia and hemoptysis from abscess erosion into the descending thoracic aorta. We report a pediatric case of an aortobronchial fistula treated with an aortic endograft and discuss the technical limitations and potential complications of this procedure.  相似文献   
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Erythropoiesis was studied in 11 subjects submitted to a 4-h hypoxia (HH) in a hypobaric chamber (4,500 m, barometric pressure 58.9 kPa) both before and after a 3-week sojourn in the Andes. On return to sea level, increased red blood cells (+3.27%), packed cell volume (+4.76%), haemoglobin (+6.55%) (P<0.05), and increased arterial partial pressure of oxygen (+8.56%), arterial oxygen saturation (+7.40%) and arterial oxygen blood content (CaO2) (+12.93%) at the end of HH (P<0.05) attested high altitude acclimatization. Reticulocytes increased during HH after the sojourn only (+36.8% vs +17.9%, P<0.01) indicating a probable higher reticulocyte release and/or production despite decreased serum erythropoietin (EPO) concentrations (–46%, P<0.01). Hormones (thyroid, catecholamines and cortisol), iron status (serum iron, ferritin, transferrin and haptoglobin) and renal function (creatinine, renal, osmolar and free-water clearances) did not significantly vary (except for lower thyroid stimulating hormone at sea level, P<0.01). Levels of 2,3-diphosphoglycerate (2,3-DPG) increased throughout HH on return (+14.7%, P<0.05) and an inverse linear relationship was found between 2,3-DPG and EPO at the end of HH after the sojourn only (r=–0.66, P<0.03). Inverse linear relationships were also found between CaO2 and EPO at the end of HH before (r=–0.63, P<0.05) and after the sojourn (r=–0.60, P=0.05) with identical slopes but different ordinates at the origin, suggesting that the sensitivity but not the gain of the EPO response to hypoxia was modified by altitude acclimatization. Higher 2,3-DPG levels could partly explain this decreased sensitivity of the EPO response to hypoxia. In conclusion, we show that altitude acclimatization modifies the control of erythropoiesis not only at sea level, but also during a subsequent hypoxia.  相似文献   
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This intervention study was to evaluate the impact of reproductive health education on the knowledge and attitude of adolescents in a rural Nigerian community to reproductive health issues. It compared adolescents in a secondary school (study group), which received health education on reproductive health with another secondary school (control group), which did not receive any. The impact of the programme was evaluated with a pre-test baseline knowledge and post-test gain in the knowledge 6 weeks later, using the same questionnaire. A total of 180 students selected by systematic sampling from each of the two randomly selected schools in Item, a rural community in south-east Nigeria participated in the programme. While all the respondents have heard of reproductive health and could identify at least one of its components, their knowledge of it prior to the health education were defective and were obtained mainly from peers and the mass media. Such information was incomplete and often coloured with cultural and religious bias. However, there was a significant (p < 0.05) gain in correct knowledge following the health education. The students in the study group showed a positive and permissive attitude towards reproductive health education and there was a drop in risky sexual behaviour following the intervention. Pre-marital sex (94.3%), pregnancy prevention and abortion (88.5%) and sexually transmitted infections (82.8%) were common reproductive health problems raised by the students. Reproductive health education as part of the school curriculum will provide an effective means of improving knowledge and reducing reproductive health problems among adolescents in developing countries.  相似文献   
10.
A case of pneumococcal pyarthrosis involving multiple joints in a moderate haemophiliac is reported. To our knowledge this is the second report of this rare complication in the English literature. Infection should be considered in an acutely inflamed joint in a haemophiliac with hyperpyrexia and unresponsive to replacement therapy. A review of the literature and our observation in this case highlight some criteria that could be used to diagnose this rare but debilitating complication early.  相似文献   
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