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51.
Scorpion venoms are very complex mixtures of molecules, most of which are peptides displaying different kinds of biological activity. Indeed, these peptides specifically bind to a variety of pharmacological targets, in particular ionic channels located in prey tissues, resulting in neurotoxic effects. Toxins modulating Na+, K+, Ca2+ and Cl(-) currents have been described in scorpion venoms. In this work, we have used several specific antibodies raised against the most lethal scorpion toxins already described to screen the Moroccan scorpion Androctonus mauretanicus mauretanicus venom in order to characterize new compounds. This immunological screening was also implemented by toxicity tests in mice and with mass spectrometry study, providing new informations on the molecular composition of this venom. In fine, we were able to determine the molecular masses of 70-80 different compounds. According to the immunological data obtained, many toxins cross-react with three sera raised against the most lethal alpha-toxins found in North African scorpion venoms, but not at all with those raised against the main beta-toxins from South and North American venoms. Some of the previously described toxins from Androctonus mauretanicus mauretanicus venom could thus be detected by combining immunological tests, toxicity in mice and molecular masses. Among these toxins, one of them, which showed a mild cross-reaction with the serum raised against AaH I (a highly potent toxin from the venom of Androctonus australis), was identified as Amm III and fully sequenced.  相似文献   
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Background  

Nearly 50% of Canadians are overweight and their number is increasing rapidly. The majority of obese subjects are treated by primary care physicians (PCPs) who often feel uncomfortable with the management of obesity. The current research proposal is aimed at the development and implementation of an innovative, integrated, interdisciplinary obesity care management system involving both primary and secondary care professionals.  相似文献   
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A complete family history was obtained for 501 patients with Wilms' tumor, treated in departments of pediatric oncology in whole France. The information was collected by self-questionnaire and/or by interview of parents. The proportion of bilateral cases is 4.6% and there are 12 patients (2.4%) with a positive family history of Wilms' tumor. The affected relatives are most often distant and no first degree relative was affected. Apart from the well-known associations with aniridia, hemihypertrophy, genitourinary anomalies, Beckwith-Wiedeemann, and Drash syndromes, there is also a significant excess of congenital heart defects (P = .008) which remains to be explained. Several findings support the bimutational hypothesis such as earlier diagnosis and increased parental age in bilateral cases. No particular anomalies and no increased frequency of childhood cancer were found in patients' relatives. The frequency of Wilms' tumor in relatives was estimated to be less than 0.4% in sibs, 0.06% in unclesand aunts, and 0.04% in first cousins. These figures are very different from those found in retinoblastoma and suggest that the mechanism may be more complex in Wilms' tumor. This conclusion is in agreement with molecular biology studies in tumors and linkage analysis in multiple case families which suggest that more than one locus is involved. © 1992 Wiley-Liss, Inc.  相似文献   
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OBJECTIVES: To assess the safety and tolerability of a topical gel formulation combining methotrexate and laurocapram and to obtain preliminary information on the therapeutic potential of methotrexate-laurocapram in patients with early-stage mycosis fungoides (stage IA or IB). DESIGN: An open-label, phase 1/2 pilot study. SETTING: Two academic referral centers. PATIENTS: Ten patients 18 years or older with histologically confirmed stage IA or IB mycosis fungoides.Intervention The gel formulation of methotrexate-laurocapram was applied to the total body surface, excluding genital, perianal areas, nipples, face, and skin under the breasts, on an every-other-day basis for 24 consecutive weeks. MAIN OUTCOME MEASURES: The safety of methotrexate-laurocapram was assessed in this study by reviewing adverse events and laboratory data. Efficacy outcomes included changes in lesion condition and severity assessments, reduction in area of sample lesions, and the investigator's global evaluation. RESULTS: Adverse events consisted of skin reactions of mild severity. No clinically significant laboratory abnormalities were observed. Based on the investigator's global evaluation at the end of the treatment phase (week 24), 7 (78%) of 9 patients demonstrated a slight-to-moderate response to treatment with methotrexate-laurocapram. Statistical significance (P =.049) was reached for induration and pruritus, a trend (P =.10) was observed for erythema, and no change was found for scaling (P =.37). CONCLUSIONS: These findings indicate that the topical administration of methotrexate-laurocapram is safe and in general well tolerated. This treatment may represent a new therapeutic potential for patients with mycosis fungoides.  相似文献   
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BACKGROUND: In response to the precipitous increase of melanoma, the American Academy of Dermatology (AAD) has coupled melanoma/skin cancer education with free skin cancer screening programs throughout the United States since 1985. The purpose of this analysis is to investigate the risk factors, access to dermatologic services, and screening results of participants in AAD-sponsored programs during the first 15 years that this service was available to the US public. METHODS: Before screening, participants completed a standardized AAD screening form. Screening forms were counted in the AAD central office and recorded in annual summaries. Forms were sent for keypunching and returned to the AAD on a computer disk annually. In 1999, disks were sent to Boston University and a master file was created. RESULTS: Computerized records were available for 819,019 screening forms and 639,835 individuals. In all, 65% of screenees had at least 1 risk factor and 33% had at least 2 risk factors. Of screenees, 33% reported a changing mole and 37% had skin type I or II. Among all screenees, nearly 80% did not have a regular dermatologist, 78% reported no prior AAD skin cancer screening, 60% had never had their skin checked by any doctor, and 51% would not have seen a doctor for skin cancer without the free screening. Nearly 30% of screenees had a presumptive diagnosis of skin cancer or a precursor lesion. Melanomas confirmed by postscreening biopsy were more likely than those in population-based registries to be less than 1.50 mm in thickness. CONCLUSIONS: AAD national screening and educational programs have expanded to all 50 states, provided educational messages about sun protection and early detection to millions, and served many US citizens with an above average risk for skin cancer and suboptimal access to dermatologic care. Screenees had a disturbingly high point prevalence of malignant and premalignant skin lesions. Sustained commitment by the AAD leadership and membership to the screening program is critical to reducing the morbidity and mortality of skin cancer.  相似文献   
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We examined the effects of feeding conjugated linoleic acids (CLA) to adult male hamsters on several components of energy metabolism and body composition. Hamsters (n = 54) were assigned for 6-8 wk to one of three diets: 1) a standard diet (in percentage energy: lipids, 33, carbohydrates, 49, and proteins, 18); 2) to the standard diet augmented with the 9c,11t-isomer of CLA to 1.6% of energy (R group); or 3) the standard diet augmented with the 9c,11t-isomer and the 10t,12c-CLA isomer to 3.2 (1.6 + 1.6) % of energy (CLA mix group). (15)N uniformly labeled milk-protein was included in the diet to measure the incorporation of dietary protein into liver and muscle. Basal metabolic rate, thermogenic response to feeding and energy expenditure during spontaneous activity or during an exercise at approximately 60% of VO(2max) were measured. Carnitine palmitoyltransferase-I (CPT-I), leptin, insulin and triiodothyronine concentrations, as well as the in vivo overall adiposity changes were also determined. After 6 wk, the whole-body triglyceride content determined in vivo by NMR was significantly higher in the R group than in the control and CLA mix groups. The CLA mix group differed from the others in the lack of body triglyceride accumulation between d 21 and d 45 of the study, and the appearance of a slight insulin-resistance (homeostatic model assessment index, P < 0.05). Paradoxically, the lack of effect on whole-body lipid oxidation was associated with a greater CPT-I-specific activity in tissues of both CLA-fed groups (P < 0.05). No other major effects of CLA feeding were detected. In conclusion, CLA supplementation in hamsters did not affect adipose weight or the components of energy expenditure despite a theoretically higher capacity of red muscle to oxidize lipids. Only a CLA mixture prevented whole-body triglyceride accumulation over time.  相似文献   
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Ewing sarcoma is the second most common bone tumor in childhood. Despite aggressive chemotherapy and radiotherapy strategies, the prognosis of patients with metastatic disease remains poor. We have recently reported that Ewing tumor cell proliferation was strongly inhibited by IFN-beta and to a lesser degree by IFN-alpha. Moreover, under IFN-beta treatment, some cell lines undergo apoptosis. Since the possibility of using IFNs for Ewing tumor treatments may be of interest, we have evaluated the efficacy of Hu-IFNs in a nude mice model of Ewing tumor xenografts. The results reported here show that human type I IFNs, Hu-IFN-alpha and Hu-IFN-beta impaired tumor xenograft take and displayed an anti-growth effect toward established xenografts. Furthermore, we have also shown that combined therapy with Hu-IFNs and ifosfamide (IFO), an alkylating agent widely used in high-dose chemotherapy of Ewing tumors, results in a strong antitumor effect. Pathological analysis showed that Hu-IFN-alpha/IFO and Hu-IFN-beta/IFO were characterized by a dramatic decrease in the mitotic index and marked necrosis, as well as extensive fibrosis associated with numerous calcifications. To our knowledge, this is the first demonstration of a potential antitumor effect of human type I IFNs and IFO on Ewing tumors, providing a rational foundation for a promising therapeutic approach to Ewing sarcoma.  相似文献   
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