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Two basic myotoxic PLA(2)s, namely BnpTX-I and II, were isolated from Bothrops neuwiedi pauloensis snake venom through three chromatographic steps: ion-exchange chromatography on CM-Sepharose, gel filtration on Sephadex G-50 and reverse phase HPLC on a C18 column. Both PLA(2)s showed a M(r) around 14,000 for the monomer and 28,000 for the dimer (as estimated by SDS-PAGE), pI approximately 7.8 and approximately 121 amino acid residues cross-linked by seven disulfide bonds. The N-terminal sequences revealed significant homology with Asp49 basic myotoxic PLA(2)s from other snake venoms. The catalytic and anticoagulant activities of BnpTX-I were higher than those of BnpTX-II. Both were able to induce cytotoxicity in vitro, as well as, myotoxicity, edema and lethality in mice. BnpTX-I also induced neurotoxic effect on mouse neuromuscular preparations and bactericidal activity on Eschericia coli and Staphylococcus aureus. After chemical modification of BnpTX-I with BPB or incubation with EDTA or Mn(2+) ions, the catalytic activity was completely abolished, while the toxic and pharmacological activities were partially reduced. Interaction with heparin inhibited the cytotoxic and bactericidal effects. Anti-BthTX-I, anti-BthTX-II and anti-115-129-C terminal antibodies strongly recognize both BnpTX-I and II. It is shown that the neurotoxic effect induced by B. neuwiedi pauloensis venom is due to the presence of myotoxic PLA(2)s. The data also corroborate the hypothesis of a partial dissociation between toxic and enzymatic domains. In addition, BnpTX-I displays a heparin binding C-terminal region, which is probably responsible for the cytotoxic and bactericidal effects.  相似文献   
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Aim. To study any discriminative properties of SF-36 and QQL-EPM in stable and non-controlled moderate asthmatic patients. Methods. A total of 63 asthmatic patients were assessed regarding asthma symptoms, FEV1 % predicted value, PEF, ED visits and hospitalizations, QQL-EPM and SF-36 questionnaires. Results. QQL-EPM highlighted significance in all domains to distinguish stable from non-controlled patients (p = 0.0001) while SF-36 was only significant in 3 of its 7 domains (p = 0.009). Conclusion. The study showed that the specific quality of life questionnaire for asthma (QQL-EPM) demonstrates better discriminative properties that characterize asthma control when compared with the more generic SF-36 questionnaire.  相似文献   
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The hepatoprotective activity of the aqueous extract of the shells of pecan nut was investigated against ethanol-induced liver damage. This by-product of the food industry is popularly used to treat toxicological diseases. We evaluated the phytochemical properties of pecan shell aqueous extract (AE) and its in vitro and ex vivo antioxidant activity. The AE was found to have a high content of total polyphenols (192.4 ± 1.9 mg GAE/g), condensed tannins (58.4 ± 2.2 mg CE/g), and antioxidant capacity, and it inhibited Fe2+-induced lipid peroxidation (LP) in vitro. Rats chronically treated with ethanol (Et) had increased plasmatic transaminases (ALT, AST) and gamma glutamyl transpeptidase (GGT) levels (96%, 59.13% and 465.9%, respectively), which were effectively prevented (87; 41 and 383%) by the extract (1:40, w/v). In liver, ethanol consumption increased the LP (121%) and decreased such antioxidant defenses as glutathione (GSH) (33%) and superoxide dismutase (SOD) (47%) levels, causing genotoxicity in erythrocytes. Treatment with pecan shell AE prevented the development of LP (43%), GSH and SOD depletion (33% and 109%, respectively) and ethanol-induced erythrocyte genotoxicity. Catalase activity in the liver was unchanged by ethanol but was increased by the extract (47% and 73% in AE and AE + Et, respectively). Therefore, pecan shells may be an economic agent to treat liver diseases related to ethanol consumption.  相似文献   
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A real-time PCR assay developed to quantify Methanobrevibacter oralis indicated that its inoculum significantly correlated with periodontitis severity (P = 0.003), despite a nonsignificant difference in prevalence between controls (3/10) and patients (12/22) (P = 0.2, Fisher test). The M. oralis load can be used as a biomarker for periodontitis.  相似文献   
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Introduction: Medical education provides students with abundant learning opportunities, each of which is embodied with messages concerning what is expected from students. This paper analyses students? exposure to instances of unprofessional behavior, investigating whether they judge such behavior to be unprofessional and whether they also participate in unprofessional behavior.

Methods: The survey developed in the Pritzker School of Medicine at the University of Chicago was the basis of this questionnaire that was answered by 276 students from two medical schools in Brazil and Portugal.

Results: Unprofessional behavior was observed frequently by students in both universities, and the mean participation rates were similar (26% and 27%). Forty-five percent of students? participation in unprofessional behavior was explained by academic year, prior observation, and judgment.

Discussion: The results indicate that once students have observed, participated in or misjudged unprofessional behavior, they tend to participate in and misjudge such behavior. The frequency with which students judged behaviors they had observed or participated in as ?borderline? or unprofessional could mean that they are experiencing moral distress.

Conclusion: Proper discussion of unprofessional behavior should foster a broad debate to encourage empowered students, faculties, and physicians to co-create a more professional environment for patient care.  相似文献   
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