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51.
Not only training but also exposure to chlorinated compounds generates a response to oxidative stimuli in swimmers 总被引:4,自引:0,他引:4
Varraso R Massin N Hery M Fradier-Dusch M Michaely JP Fournier M Hubert G Biette P Rieger B Berthelin A Hecht G Nadif R 《Toxicology and industrial health》2002,18(6):269-278
Relations between exposure to chlorinated compounds and biological markers of response to oxidative stimuli were investigated in swimmers, taking into account the effect of training. Twenty-two male swimmers aged 15-25 years were surveyed twice. Prevalence of irritant symptoms and asthma and number of hours of training were reported. Exposure to nitrogen trichloride (NCl3) and blood response to oxidative stimuli [catalase, superoxide dismutase (Cu2+/Zn2+ SOD), glutathione peroxidase (GSH-Px) activities and ceruloplasmin, ferritin and total antioxidant concentrations] were measured. Univariate analyses were completed by multivariate analyses. High prevalences of irritant symptoms and asthma were found. Multivariate analysis confirmed the results of the univariate analyses and showed that Cu2+/Zn2+ SOD activity was increased by exposure and by training (P = 0.01, P = 0.0001, respectively). Erythrocyte GSH-Px was decreased, whereas plasma GSH-Px was increased by exposure (P = 0.002, P = 0.002). No other association was found. Higher irritant symptoms and increases in the activities of erythrocyte Cu2+/Zn2+ SOD and of plasma GSH-Px with exposure support the hypothesis that the production of reactive oxygen species is not only related to training but also to exposure to chlorinated compounds. Other athletes tend to have respiratory problems such as asthma, but the exposure to chlorinated compounds may increase the respiratory disease among swimmers. 相似文献
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53.
Foligne B Sénégas-Balas F Antoine JM Cayuela C Rolf-Pedersen N Balas D 《Digestive diseases and sciences》2004,49(7-8):1291-1301
Among the multifactorial causes of undernutrition in old age, gastrointestinal mucosa altered function and resulting specific malabsorption are the most relevant. Despite numerous studies that have dealt with the effects of aging on the digestive tract of mammals, results showed discrepancies in terms of proliferation and biochemical aging small intestine events. However, the slowing-down of the maturation process and the poor adaptation of metabolism and intestinal function are obvious and there is evidence that protective mechanisms are impaired with age and contribute to affecting the trophic activity and related systemic homeostasis. Good prospects to improve gastrointestinal function in the elderly are essential and research on nutritional intervention to limit and counteract age-related impairments must be extensive. Probiotics are good candidates and fermented milks might be of great interest. In the present study we first show the main structural and functional variations between 3- and 23-month-old rat small intestines. The trophic consequences of aging and nutritional adaptation under basal conditions are also analyzed and discussed after 20 days of a yogurt-supplemented specific diet in both young and aged rats. The main variations that occur with aging and yogurt diet are located in the proximal small intestine. The present findings indicate a slight improvement of morphological trophic parameters in both young and aged rats by yogurt, whereas enzymatic changes are more discrete. Despite the obvious age-related decrease in trophicity, we suggest that assessment of probiotic potentials on trophicity requires a more altered model than normal, healthy aging animals. 相似文献
54.
Côté AM Sobela F Dzokoto A Nzambi K Asamoah-Adu C Labbé AC Mâsse B Mensah J Frost E Pépin J 《AIDS (London, England)》2004,18(6):917-925
OBJECTIVE: To delineate the population attributable fraction (PAF) of transactional sex in prevalent cases of HIV infection in the male adult population of Accra, Ghana. DESIGN AND METHODS: Cross-sectional study of clients who visited a sex worker (SW), of boyfriends of SW and of male personnel in prostitution venues. A questionnaire was administered and urine obtained for detection of anti-HIV antibodies. The PAF of prevalent HIV acquired from SW was calculated using a combination of data from this survey of clients, from on-going SW surveys, the national HIV surveillance system and the national census. RESULTS: HIV prevalence was 4.9% (8/162) among clients of mobile SW, 15.8% (53/335) among clients of home-based SW, 17.5% (10/57) among personnel and 32.1% (9/28) among boyfriends. A condom was used in 90% of intercourses, according to clients. Non-use of a condom was clustered in selected locations and independently associated with older age of client, frequency of intercourse with SW in the last year and current urethritis. Among the male population of Accra aged 15-59 years, 84% of prevalent cases of HIV were attributable to transactional sex. A sensitivity analysis showed that under various assumptions PAF varied between 47% and 100%. CONCLUSIONS: In Accra, approximately four-fifths of prevalent cases of HIV in adult males were acquired from SW. Comprehensive interventions providing education, condoms and treatment for sexually transmitted diseases for SW and their clients should be approached as other public health priorities and provided in all cities, large and small, of West Africa. 相似文献
55.
Autopsies of exhumed cadavers can reveal important evidence for clarification of medical insurance and social issues. This study concerns insects sampled on 22 exhumed cadavers in the Lille area. For each corpse, the species and the stages of development were noted, as well as the time elapsed after burial, the location of the cemetery, the stage of decay and possible preservation treatment. A total of eight Diptera and two Coleoptera species were sampled on the corpses. The relationships between entomofauna and conditions of burial are discussed. Three species were regularly found because of their preference for underground environments or closed environments: Conicera tibialis, typically associated with buried bodies, Leptocera caenosa which is known to be associated with human faeces, water closets, caves and cracked soil pipes, and Ophyra capensis, sometimes found on human bodies kept indoors for several months, where blowflies have not had access. Triphleba hyalinata, which is associated with human bodies in wooden coffins, was found only twice. 相似文献
56.
Proulle V Hugel B Guillet B Trichet C Rafowicz A Lambert T Freyssinet JM Dreyfus M 《Thrombosis and haemostasis》2004,91(5):873-878
Recombinant activated factor VII (rFVIIa) is an effective haemostatic treatment in haemophiliacs with inhibitors. In vitro, FVIIa concentrations corresponding to those obtained with therapeutic doses of rFVIIa have been shown to induce normal thrombin generation and platelet activation in the absence of factors VIII or IX. To further study the in vivo haemostatic changes induced by rFVIIa, circulating procoagulant microparticles (MP) were measured in patients treated with discontinuous injections of Novoseven. In 6 out of 15 patients, a transient peak of procoagulant MP was observed after injection, occurring 15 min to 2 h after infusion. It was composed primarily of platelet-derived MP and was of very short duration. This peak was not observed in haemophiliacs without inhibitor, who were treated with conventional replacement therapies. Our results provide further in vivo evidence that rFVIIa specifically activates platelets, either directly or as a consequence of a burst of thrombin generation that could account for its haemostatic efficacy. 相似文献
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58.
Intracytoplasmic filamentous aggregates, such as neurofibrillary tangles in Alzheimer's disease and Lewy bodies in Parkinson's disease, are composed of the proteins tau and alpha-synuclein, respectively. These pathological inclusions are linked directly to the etiology and mechanisms of disease in a wide spectrum of neurodegenerative disorders, termed 'tauopathies' and 'synucleinopathies'. Emerging evidence indicates that there is frequent overlap of the pathological and clinical features of patients with tauopathies and synucleinopathies, thereby re-enforcing the notion that these disorders might be linked mechanistically. Indeed, several lines of investigation suggest that tau and alpha-synuclein might constitute a unique class of unstructured proteins that assemble predominantly into homopolymeric (rather than heteropolymeric) fibrils, which deposit mainly in separate amyloid inclusions, but occasionally deposit together. Thus, the ability of tau and alpha-synuclein to affect each other directly or indirectly might contribute to the overlap in the clinical and pathological features of tauopathies and synucleinopathies. 相似文献
59.
Surgical management of primary hyperparathyroidism: the case for giving up quick intraoperative PTH assay in favor of routine PTH measurement the morning after 下载免费PDF全文
OBJECTIVE: To analyze the utility of quick intraoperative parathyroid hormone (PTH) measurement in the surgical management of primary hyperparathyroidism. BACKGROUND DATA: The use of intraoperative PTH monitoring is well established in the surgery of primary hyperparathyroidism. However, some false-negative predictions lead to unnecessary explorations; furthermore, surgeons are becoming increasingly dependent on hormone measurement for intraoperative decisions, which raises concerns about the cost-effectiveness of the method. METHODS: A retrospective analysis of 268 neck explorations performed for primary hyperparathyroidism using intraoperative PTH monitoring from April 2001 to February 2003 was done. We used the criterion of "biologic recovery" of hyperfunctioning tissue, defined as a more than 50% decrease in PTH level from baseline value at 5 minutes after excision to predict the outcome of successful parathyroidectomy documented by normal postoperative serum calcium level. Additionally, we also sampled PTH at 10 minutes, 30 minutes, and the morning after surgery to compare the predictive value of delayed sampling. Patients were classified according to the prediction being concordant or discordant with the outcome. The data were analyzed using a 2 x 2 table construct for each of the sampling times, therefore providing sequential sensitivity, specificity, positive and negative predictive values, and overall accuracy of the predictions. RESULTS: Concordance or overall accuracy of prediction (true positives and negatives) was obtained in 229 cases (85.4%), and discordance or failure of prediction (false positives and negatives) was obtained in 34 cases (12.7%) at T5. On analyzing the iPTH prediction at T10, T30, and D1 among the group of 33 false negatives, we found that 28 (10.4%) patients reached the concordance at 30 minutes, while by the first day 32 patients (12.3%) had achieved concordance. Thus, there was a progressive increase in sensitivity and overall accuracy, but more importantly, in the negative predictive value reaching 88.9% on the day after surgery. CONCLUSIONS: The method of sampling PTH intraoperatively at 5 minutes has a high positive predictive value (99.5%) but a low negative predictive value (19.5%), which can lead to unnecessary explorations and a delay in the operative procedure. The negative predictive value increases substantially at 30 minutes and is best on the day after surgery. We suggest giving up the intraoperative measurement of PTH to adopt the first day postoperative measurement of PTH as a predictor of successful parathyroidectomy. 相似文献
60.
Chapelier AR Missana MC Couturaud B Fadel E Fabre D Mussot S Pouillart P Dartevelle PG 《The Annals of thoracic surgery》2004,77(3):1001-6; discussion 1006-7
BACKGROUND: Primary malignant sternal tumors (PMST) are locally aggressive and their optimal surgical management still continues to evolve. METHODS: From 1986 to 2002, 38 patients (25 females/13 males) underwent radical resection of PMST. This series included 33 sarcomas, 17 of which had been radiation-induced, 3 hematologic tumors, and 2 carcinomas. Seventeen were high-grade tumors. Nine patients had received preoperative chemotherapy. Twelve patients required extensive skin excision. Eight total, seven subtotal, and 23 partial sternectomies were performed. Resection was extended to the anterior chest-wall in 4 patients, lung in 4, brachiocephalic vein in 3, superior vena cava in 2, and pericardium in 1. In 36 patients, chest wall stability was obtained by Marlex (n = 21) or Vicryl (n = 2) mesh and polytetrafluoroethylene patch (n = 13), with methylmethacrylate reinforcement in 12 patients. Soft tissue coverage was done by the pectoralis major muscles with skin advancement in 25 patients, a myocutaneous flap in 11, a breast transposition in 1, and a skin flap in 1. Omentoplasty was performed in 3 patients. RESULTS: One patient died from pneumonia. Two patients needed a tracheostomy after total sternectomy. No flap-related complication was observed. Four local septic complications required removal of the composite prosthesis with reoperations. Local recurrence occurred in 9 patients, 7 patients having a repeat resection. Metastases developed in eight. The 5-year overall and disease-free survival was 66% and 53%, respectively. The histologic grade of sarcomas was a survival predictor (high grade versus others p = 0.035). CONCLUSIONS: Wide resection of PMST is necessary to minimize local recurrence. Large sternal defects are safely reconstructed with a musculocutaneous flap. We suggest that the use of methylmethacrylate should be limited to reconstruction after total sternectomy. 相似文献