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61.
Léa Rodrigues-Simioni Stella R Zamunér José C Cogo Caroline R Borja-Oliveira Júlia Prado-Franceschi Maria Alice da Cruz-H?fling Alexandre P Corrado 《Toxicon》2004,43(6):633-638
Whereas the presynaptic action of Crotalus durissus terrificus venom is well-established, Bothrops venoms have historically been considered to have only postsynaptic and muscular effects. However, some studies have also suggested a presynaptic action for these venoms. In this work, we used chick biventer cervicis preparations to compare the presynaptic actions of two Bothrops venoms (B. insularis and B. neuwiedi) with that of C. d. terrificus venom. At 10 microg/ml, all venoms produced irreversible blockade of the twitch tension responses, with no reduction in acetylcholine (ACh)-induced contractures and only a slight decrease in potassium induced-contractures. The times (in min) required to produce 50% neuromuscular blockade (C. d. terrificus: 16.3+/-0.7, n = 8; B. insularis: 30.0+/-1.9, n = 5; B. neuwiedi: 42.0+/-2.0, n = 8; mean +/- SEM) were significantly different among the venoms (p < 0.01). Lowering the temperature at which the experiments were done (from 37 to 24 degrees C) prevented neuromuscular blockade by the three venoms, indicating that enzyme activity may be involved in this response. At concentrations capable of causing complete neuromuscular blockade, creatine kinase release remained close to levels seen in control preparations incubated with Krebs solution alone (500-1200 IU/l). Commercial crotalic antivenom, but not bothropic antivenom, protected against the neuromuscular blockade caused by B. insularis and B. neuwiedi venoms. These observations indicate that bothropic venoms may contain components which act presynaptically in a manner similar to C. d. terrificus venom, and that at low venom concentrations a direct action on skeletal muscle does not contribute to this presynaptic neurotoxicity. 相似文献
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Today, only a limited number of training courses specifically in human health risk assessment are available in Europe and although some basic training in health risk assessment is part of most toxicology university programmes, the preparation is often not enough. The purpose of this commentary is to present provision of training program in risk assessment based on common European criteria, easily adopted by institutions across Europe and focusing on risk assessment methodology and procedure. It is worth mentioning that the following paper does not deal with microbiological risk assessment and ecotoxicological risk assessment but mainly with chemical risk assessment. The project focuses on understanding the profile and training requirements of risk assessors in order to design a modular training program covering a range of disciplines in risk assessment and providing a model to establish guidelines for the training and recognition of risk assessors in accordance to a well-defined and properly acknowledged training standard. 相似文献
63.
S. Roperto V. Russo L. Leonardi M. Martano F. Corrado M. G. Riccardi F. Roperto 《Transboundary and Emerging Diseases》2016,63(6):628-634
Bovine papillomavirus type 13 (BPV‐13), a novel Deltapapillomavirus, has been found associated with urothelial tumours of the urinary bladder of cattle grazing on lands infested with bracken fern. BPV‐13 was detected in 28 of 39 urothelial tumours. Diagnosis was based on sequencing of L1 and E5 amplicons from tumour samples. The nucleotide sequences generated from these amplicons showed a 100% homology with the sequences of BPV‐13 L1 and E5 DNA found in Brazil from a fibropapilloma of the ear in a cow and from equine sarcoids in two horses. GenBank accession number of our representative BPV‐13 sequences is JQ798171.1 . Furthermore, mRNA encoding BPV‐13 E5 oncoprotein was also documented, and its expression was also shown by immunohistochemistry and immunofluorescence in the basal and suprabasal urothelial tumour cells. In twenty‐three tumours, BPV‐13 was simultaneously found with BPV‐2, a Deltapapillomavirus genus, species 4. The latter virus was detected by amplifying and sequencing a 154‐bp‐sized DNA fragment of BPV‐2 E5. In addition, BPV‐13 by itself was seen to be expressed in five BPV‐2‐negative urothelial tumours. This study shows that BPV‐13 is present in urothelial tumour cells thus sharing biological properties with BPV‐1 and BPV‐2. Although further studies are needed, BPV‐13 appears to be another worldwide infectious agent responsible for a distressing disease causing severe economic losses in cattle industry. 相似文献
64.
L Manzoli V Simonetti MM D'Errico C De Vito ME Flacco C Forni G La Torre G Liguori G Messina A Mezzetti M Panella C Pizzi R Siliquini P Villari G Cicolini 《Journal of hypertension》2012,30(10):1955-1960
OBJECTIVES:: The diagnosis and control of hypertension depend on accurate measurement of blood pressure (BP). The literature on the accuracy of BP recording by health professionals is, however, limited, and no study directly interviewed patients in the hospital setting. This multicenter cross-sectional study aimed at evaluating the compliance to current recommendations on BP measurement by health professionals directly from patients and to investigate potential predictors of higher quality in BP recording. METHODS:: A trained nurse interviewed a random sample of adult patients hospitalized for an ordinary admission (except in the emergency room) lasting more than one night, without mental disorder, who had their BP routinely measured by the hospital personnel less than 3?h before. The questionnaire contained 15 items on the main procedures that are common to current guidelines. RESULTS:: Fourteen public hospitals from seven regions of Italy participated, and 1334 questionnaires were collected. Nine of the recommended practices were followed in the majority (>70%) of BP recordings, whereas some others were infrequent or rare: in 98.6, 82.2 and 81.1% of the participants, respectively, the arm circumference was never recorded, BP was measured only once, and BP was never recorded in both arms. Overall, 10 or more recommended procedures were followed during 33.4% recordings. At multivariate analysis, physicians were less likely than nurses to provide a more accurate BP measurement. CONCLUSIONS:: The operator's compliance to some recommendations in BP measurement is unacceptably low. This survey provides detailed indications for medical directors on the procedures and settings to prioritize in educational programs, which are definitely needed. 相似文献
65.
Treatment of Rheumatoid Arthritis With Anti–Tumor Necrosis Factor or Tocilizumab Therapy as First Biologic Agent in a Global Comparative Observational Study 下载免费PDF全文
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Giacomo Mugnai Mariantonietta Cicoira Andrea Rossi Corrado Vassanelli 《Experimental & Clinical Cardiology》2011,16(2):51-53
Primary systemic amyloidosis is a relatively uncommon disease characterized by the production and deposition of pathological insoluble fibrillar proteins in organs and tissues. It has been estimated that between one-third and one-half of all patients with primary amyloidosis experience clinically significant cardiac involvement. The present study reports a case involving a 77-year-old woman with ischemic heart disease who presented to the cardiology department because of syncope due to slow atrial fibrillation. Laboratory tests revealed a monoclonal spike in the gamma fraction and impairment of renal function, normocytic anemia, mild hypercalcemia, hypoalbuminemia and increased levels of beta-2 microglobulin. Suspicion of cardiac involvement was supported by the echocardiographic pattern and increased levels of troponin I and brain natriuretic peptide, along with clinical signs of heart failure and systemic amyloidosis diagnosis, confirmed by abdominal fat aspiration. 相似文献