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51.
Juliana Pavan Zuliani José María Gutiérrez Luciana Lyra Casais e Silva Sandra Coccuzzo Sampaio Bruno Lomonte Catarina de Fátima Pereira Teixeira 《Toxicon》2005,46(5):523-532
The in vitro effects of myotoxin III (MT-III), an Asp-49 catalytically-active phospholipase A(2), and myotoxin II (MT-II), a catalytically-inactive Lys-49 variant, isolated from Bothrops asper snake venom, on phagocytosis and production of hydrogen peroxide (H(2)O(2)) by thioglycollate-elicited macrophages were investigated. MT-II and MT-III were cytotoxic to mouse peritoneal macrophages at concentrations higher than 25 microg/ml. At non-cytotoxic concentrations, MT-II stimulated Fcgamma, complement, mannose and beta-glucan receptors-mediated phagocytosis, whereas MT-III stimulated only the mannose and beta-glucan receptors-mediated phagocytosis. Moreover, both myotoxins induced the release of H(2)O(2) by thioglycollate-elicited macrophages, MT-III being the most potent stimulator. MT-II induced the release of H(2)O(2) only at a concentration of 3.2 microg/ml (130% increment) while MT-III induced this effect at all concentrations tested (0.5-2.5 microg/ml; average of 206% increment). It is concluded that, at non-cytotoxic concentrations, MT-II and MT-III activate defense mechanisms in macrophages up regulating phagocytosis, mainly via mannose and beta-glucan receptors, and the respiratory burst. 相似文献
52.
Stella Regina Zamuner Juliana Pavan Zuliani Cristina Maria Fernandes José Maria Gutiérrez Catarina de Fátima Pereira Teixeira 《Toxicon》2005,46(7):806-813
Bothrops asper venom (BaV) causes systemic and local effects characterized by an acute inflammatory reaction with accumulation of leukocytes and release of endogenous mediators. In this study, the effects of BaV on the release of the cytokines IL-1, IL-6 and TNF-alpha and the eicosanoids LTB4 and TXA2 in the peritoneal cavity of mice were analyzed. We also investigated the participation of beta2 integrin chain, l-selectin, LFA-1, ICAM-1 and PECAM-1 adhesion molecules in the BaV-induced leukocyte accumulation. Levels of proinflammatory cytokines IL-6 and TNF-alpha, as well as eicosanoids LTB4 and TXA2 were significantly increased after BaV injection (250 microg/kg), whereas no increment in IL-1 was observed. Anti-mouse l-selectin, LFA-1, ICAM-1, PECAM-1 and beta2 integrin chain monoclonal antibodies resulted in a reduction of neutrophil accumulation induced by BaV injection compared with isotype-matched control injected animals. These data suggest that BaV is able to induce the activation of leukocytes and endothelium to express adhesion molecules involved in the recruitment of neutrophils into the inflammed site. Furthermore, these results showed that BaV induces the release of cytokines and eicosanoids in the local of the venom injection; these inflammatory mediators may be important for the initiation and amplification of the inflammatory reaction characteristic from Bothrops sp envenomation. 相似文献
53.
Eduardo Pernambuco de Souza Marcelo de Souza Teixeira 《Revista do Instituto de Medicina Tropical de S?o Paulo》2014,56(4):307-311
The aim of this cross-sectional study was to determine the hepatitis B
vaccination coverage among medical students at a public university in Rio de Janeiro,
Brazil, and their compliance with the postvaccination serologic testing
recommendations. Of the total of 858 students, 675 (78.7%) participated in the study.
Among the participants, 48.9% (95% CI: 45.1% to 52.7%) were vaccinated against
hepatitis B (received ≥ 3 doses of the vaccine), 31.6% were not (received 0, 1 or 2
doses), and 19.6% did not know their vaccination status. Hepatitis B vaccination
coverage increased from 26.0% among first-year students to 70.6% among sixth-year
students while the prevalence of unknown vaccination status decreased from 39.7%
among first-year students to 2.4% among sixth-year students. The frequency of
unvaccinated students ranged from 23.7% among fifth-year students to 34.4% among
first-year students. Only 34.8% of the vaccinated students performed the anti-HBs
testing after vaccination. Among these medical students, we found a low adherence to
the hepatitis B vaccination and to the postvaccination serologic testing. A
comprehensive hepatitis B immunization program should be offered to students at this
medical school. 相似文献
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56.
Liz Girardi Müller Camila Simonetti Pase Patrícia Reckziegel Raquel C.S. Barcelos Nardeli Boufleur Ana Cristina P. Prado Roseane Fett Jane Mara Block Maria Amália Pavanato Liliane F. Bauermann João Batista Teixeira da Rocha Marilise Escobar Burger 《Experimental and toxicologic pathology》2013,65(1-2):165-171
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
57.
Izabela Guimarães Barbosa Natália Pessoa Rocha Aline Silva de Miranda Rodrigo Barreto Huguet Moisés Evandro Bauer Helton José Reis Antônio Lúcio Teixeira 《Revista brasileira de psiquiatria (S?o Paulo, Brazil : 1999)》2013,35(1):67-69
IntroductionBipolar disorder (BD) is a prevalent, chronic and progressive illness. There is a growing body of evidence indicating that brain-derived neurotrophic factor (BDNF) plays an important role in the pathophysiology of BD.ObjectiveThe aim of this study was to evaluate BDNF plasma levels in BD patients with long term illness in comparison with controls.Methods87 BD type I patients and 58 controls matched by age, gender and education level were enrolled in this study. All subjects were assessed by the Mini-International Neuropsychiatric Interview and the patients by the Young Mania Rating Scale and the Hamilton Depression Rating Scale. The plasma levels of BDNF were measured by ELISA.ResultsOn average, patients had suffered from BD for 23.4 years. In comparison with controls, BD patients with mania presented a 1.90-fold increase in BDNF plasma levels (p = .001), while BD patients in remission presented a 1.64-fold increase in BDNF plasma levels (p = .03). BDNF plasma levels were not influenced by age, length of illness or current medications.ConclusionsThe present study suggests that long-term BD patients exhibit increased circulating levels of BDNF. 相似文献
58.
G.R. Coêlho B.A. Feitosa NetoC.C. de G. Teixeira D.S. MarinhoM.L.M. Rangel J.H.P. Garcia 《Transplantation proceedings》2013
Orthotopic liver transplantation (OLT) is the treatment of choice for patients with acute or chronic end-stage liver disease, irresectable primary liver tumor, and metabolic disorders. Historically, OLT has been associated with considerable blood loss and the need for transfusions. However, over the years there has been reduction is need for blood products. The aim of this article was to compare two distinct eras for perioperative blood transfusion rate among patients undergoing OLT; Era I, 200 transplantations in 188 patients, and Era II, 355 transplantations in 339 patients. The donor mean age was 33.70 (Era I) versus 35.34 (Era II). Cause of death in both eras was traumatic brain injury followed by cerebral vascular accident. Organ recipient data showed a mean age of 48.87 (Era I) versus 46.49 (Era II). During Era I patients with Child B (56.8%) prevailed, followed by Child C (35.4%) and Child A (7.8%). In Era II also patients with Child B (53.1%) prevailed, followed by Child C (39.6%) and Child A (7.3%). The prevalence of hepatocellular carcinoma (HCC) during Era I was 9% (18) and in Era II 20% (71). The use of blood products in the perioperative period: was as follows packed red blood cells 1.76 (Era I) versus 0.57 (Era II) units; fresh frozen plasma 1.89 (Era I) versus 0.49 (Era II) units; platelets 2.16 (Era I) versus 0.28 (Era II) units; and cryoprecipitate 0.08 (Era I) versus 0.03 (Era II) units. OLT using the piggyback technique was performed with a transfusion rate below <30%, and it reduced blood loss and prevented severe hemodynamic instability. 相似文献
59.
Fernanda Rodrigues Helmo Juliana Reis Machado Camila Souza de Oliveira Guimar?es Vicente de Paula Antunes Teixeira Marlene Ant?nia dos Reis Rosana Rosa Miranda Corrêa 《Disease markers》2013,35(6):939-944
Fetal skin has the intrinsic capacity for wound healing, which is not correlated with the intrauterine environment. This intrinsic ability requires biochemical signals, which start at the cellular level and lead to secretion of transforming factors and expression of receptors, and specific markers that promote wound healing without scar formation. The mechanisms and molecular pathways of wound healing still need to be elucidated to achieve a complete understanding of this remodeling system. The aim of this paper is to discuss the main biomarkers involved in fetal skin wound healing as well as their respective mechanisms of action. 相似文献
60.
Pedro Gouveia Catarina Silva Fátima Magalhães Claúdia Santos Emanuel Guerreiro Filipe Santos Teixeira Gomes 《International journal of surgery case reports》2013,4(5):524-527
INTRODUCTIONAngiosarcoma is a very rare entity of soft tissue neoplasm with an aggressive and destructive biological behavior. Thyroid angiosarcoma is usually reported in Alpine regions, with only exceptionally rare cases arising in non-mountainous areas. In the Alpine regions it constitutes 2–10% of all malignant thyroid tumors.PRESENTATION OF CASEWe report a case of a thyroid non-Alpine angiosarcoma in a 71-year-old female with a 10 years old multinodular goiter. The cervical mass underwent rapid growth in the last year, and she was referred for surgical treatment. A 15 cm mass was found on the right side of the neck invading adjacent tissues and displacing the trachea without obvious invasion of this organ. Fine needle aspiration cytology showed “carcinoma”. Lung metastasis were present. Although difficult, total thyroidectomy was possible with resection of an esophageal implant. Post-operatively, she had respiratory failure that eventually recovered, but, on 39th post-operative day, she died of violent hemoptysis, probably due to invasion by mediastinal metastasis.DISCUSSIONA clear distinction between angiosarcoma and anaplastic carcinoma of the thyroid is considerably difficult, despite treatments and prognosis are practically the same. However, in recent years, a thyroid malignancy exhibiting phenotypical features of endothelial differentiation was described. Keratin positivity cannot be reported as necessarily indicative of epithelial differentiation.CONCLUSIONOptimal treatment for thyroid angiosarcoma remains unclear, not only because the prognosis is poor, despite multimodal therapeutic efforts, but also because it is a very rare entity. 相似文献