1000 resultados para Faustino, Mário
Resumo:
Propolis possesses various biological activities such as antibacterial, antifungal, anti-inflammatory, anesthetic and antioxidant properties. A topically applied product based on Brazilian green propolis was developed for the treatment of burns. For such substance to be used more safely in future clinical applications, the present study evaluated the mutagenic potential of topical formulations supplemented with green propolis extract (1.2, 2.4 and 3.6%) based on the analysis of chromosomal aberrations and of micronuclei. In the in vitro studies, 3-h pulse (G(1) phase of the cell cycle) and continuous (20 h) treatments were performed. In the in vivo assessment, the animals were injured on the back and then submitted to acute (24 h), subacute (7 days) and subchronic (30 days) treatments consisting of daily dermal applications of gels containing different concentrations of propolis. Similar frequencies of chromosomal aberrations were observed for cultures submitted to 3-h pulse and continuous treatment with gels containing different propolis concentrations and cultures not submitted to any treatment. However, in the continuous treatment cultures treated with the 3.6% propolis gel presented significantly lower mitotic indices than the negative control. No statistically significant differences in the frequencies of micronuclei were observed between animals treated with gels containing different concentrations of propolis and the negative control for the three treatment times. Under the present conditions, topical formulations containing different concentrations of green propolis used for the treatment of burns showed no mutagenic effect in either test system, but 3.6% propolis gel was found to be cytotoxic in the in vitro test.
Resumo:
The peritoneal cavity (PerC) is a singular compartment where many cell populations reside and interact. Despite the widely adopted experimental approach of intraperitoneal (i.p.) inoculation, little is known about the behavior of the different cell populations within the PerC. To evaluate the dynamics of peritoneal macrophage (Mempty set) subsets, namely small peritoneal Mempty set (SPM) and large peritoneal Mempty set (LPM), in response to infectious stimuli, C57BL/6 mice were injected i.p. with zymosan or Trypanosoma cruzi. These conditions resulted in the marked modification of the PerC myelo-monocytic compartment characterized by the disappearance of LPM and the accumulation of SPM and monocytes. In parallel, adherent cells isolated from stimulated PerC displayed reduced staining for beta-galactosidase, a biomarker for senescence. Further, the adherent cells showed increased nitric oxide (NO) and higher frequency of IL-12-producing cells in response to subsequent LPS and IFN-gamma stimulation. Among myelo-monocytic cells, SPM rather than LPM or monocytes, appear to be the central effectors of the activated PerC; they display higher phagocytic activity and are the main source of IL-12. Thus, our data provide a first demonstration of the consequences of the dynamics between peritoneal Mempty set subpopulations by showing that substitution of LPM by a robust SPM and monocytes in response to infectious stimuli greatly improves PerC effector activity.
Resumo:
We construct a nonrelativistic wave equation for spinning particles in the noncommutative space (in a sense, a theta modification of the Pauli equation). To this end, we consider the nonrelativistic limit of the theta-modified Dirac equation. To complete the consideration, we present a pseudoclassical model (a la Berezin-Marinov) for the corresponding nonrelativistic particle in the noncommutative space. To justify the latter model, we demonstrate that its quantization leads to the theta-modified Pauli equation. We extract theta-modified interaction between a nonrelativistic spin and a magnetic field from such a Pauli equation and construct a theta modification of the Heisenberg model for two coupled spins placed in an external magnetic field. In the framework of such a model, we calculate the probability transition between two orthogonal Einstein-Podolsky-Rosen states for a pair of spins in an oscillatory magnetic field and show that some of such transitions, which are forbidden in the commutative space, are possible due to the space noncommutativity. This allows us to estimate an upper bound on the noncommutativity parameter.
Resumo:
BACKGROUND: Nisin is a commercially available bacteriocin produced by Lactococcus lactis ATCC 11454 and used as a natural agent in the biopreservation of food. In the current investigation, milk whey, a byproduct from dairy industries was used as a fermentation substrate for the production of nisin. Lactococcus lactis ATCC 11454 was developed in a rotary shaker (30 degrees C/36 h/100 rpm) using two different media with milk whey (i) without filtration, pH 6.8, adjusted with NaOH 2 mol L-1 and without pH adjustment, both autoclaved at 121 degrees C for 30 min, and (ii) filtrated (1.20 mu m and 0.22 mu m membrane filter). These cultures were transferred five times using 5 mL aliquots of broth culture for every new volume of the respective media. RESULTS: The results showed that culture media composed of milk whey without filtration supplied L. lactis its adaptation needs better than filtrated milk whey. Nisin titers, in milk whey without filtration (pH adjusted), was 11120.13 mg L-1 in the second transfer, and up to 1628-fold higher than the filtrated milk whey, 6.83 mg.L-1 obtained in the first(t) transfer. CONCLUSIONS: Biological processing of milk byproducts (milk whey) can be considered a profitable alternative, generating high-value bioproducts and contributing to decreasing river disposals by dairy industries. (C) 2008 Society of Chemical Industry.
Resumo:
Background: Evidence indicates that infection with Ascaris lumbricoides may promote development of allergy and asthma. Objective: To study the role of tropomyosin, a pan-allergen in invertebrates, in IgE responses to A lumbricoides. Methods: Recombinant A lumbricoides and Periplaneta americana tropomyosins were expressed in Pichia pastoris. Levels of IgE to tropomyosins from A lumbricoides and P americana were determined by chimeric ELISA in sera from 119 children living in a parasite-endemic area and 112 patients with cockroach allergy from the allergy clinics. Presence of tropomyosin in A lumbricoides larvae at L3 stage was evaluated by immunofluorescence using mAb IA6, directed against mite tropomyosin. Molecular modeling of P americana and A lumbricoides tropomyosins was performed by using the MODELLER program. Results: A lumbricoides tropomyosin showed 69% to 98% sequence identity to tropomyosins from other invertebrates. The predicted structure of A lumbricoides tropomyosin was similar to that of P americana tropomyosin and showed the characteristic coiled-coil structure. Strong correlation was found for IgE antibodies to tropomyosins from A lumbricoides and P americana in sera from children living in a parasite-endemic area and from patients with cockroach allergy. Larvae of A lumbricoides reacted strongly with mAb IA6. Conclusion: Tropomyosin induces IgE responses in A lumbricoides-infected children and in patients allergic to cockroach.
Resumo:
During the process of maturation in the oviduct, canine oocytes in the germinal vesicle stage are exposed to decreasing levels of estradiol-17 beta and increasing levels of progesterone. However, hormone concentrations in the microenvironments in which they act are higher than serum concentrations. Therefore, the aim of the present study was to compare the meiotic competence of canine oocytes harvested from anestrous bitches in culture medium containing high concentrations (20 mu g ml(-1)) of estradiol-17 beta and/or progesterone in association to gonadotropins (luteinizing hormone and follicle-stimulating hormone) using three different maturation periods (48, 72, and 96 h). Oocytes were cultured in tissue culture medium (TCM-199) and arranged in four experimental groups: group control, group E2 (estradiol-17 beta), group P4 (progesterone), and group E2 + P4. Regardless of the maturation period, groups P4 and E2 + P4 presented statistically higher rate of germinal vesicle breakdown oocytes compared to the group control and group E2. There were no significant differences among groups on germinal vesicle, metaphase I, metaphase II, and degenerated or unidentifiable oocytes rates. The mean percentage of metaphase II oocytes was higher at 96 h when compared to 72 h. Results of the present research indicate no influence of estradiol-17 beta supplementation, unless in association with progesterone. There is an evidence of the positive effect of progesterone on germinal vesicle breakdown. Results also showed that extended periods of in vitro maturation affect positively maturation rates to metaphase II of low competent oocytes harvested from anestrous bitches, independent of the maturation media. In conclusion, high concentrations of steroids, especially progesterone, have positive effect on in vitro oocyte maturation when the oocytes are derived from the anestrous status.
Resumo:
A case of peripheral odontogenic keratocyst arising in it 57-year-old white female patient involving the posterior mandibular gingiva that recurred after 12 months of fellow-up is presented. This reported case reinforces that patients presenting peripheral odontogenic keratocyst should be carefully followed up after conservative surgical treatment.
Resumo:
Strong vascular endothelial growth factor-C (VEGF-C) expression has been correlated to occurrence of lymph-node metastases in patients with oral squamous cell carcinoma (OSCC). The incidence of occult lymph-node metastasis remains a decisive factor in the prognosis of patients with early OSCC. The aim of this study was to evaluate VEGF-C expression as a predictor of occult lymph-node metastasis in OSCC. Eighty-seven patients with primary OSCC arising in the tongue or floor of mouth, clinically T1N0M0 or T2N0M0, with (pN+) and without (pN0) occult lymph-node metastases were analyzed for VEGF-C expression by malignant cells. Occult lymph-node metastases (pN+) were detected in 22% of the 64 patients who were submitted to elective neck dissection. No statistically significant difference was found between OSCC with and without occult lymph-node metastasis in regard to VEGF-C immunoexpression by malignant cells and clinicopathologic features. Independently of VEGF-C expression, lymph-node metastasis (PN+) was the most significant prognostic factor for overall survival of patients with OSCC (p = 0.030). These findings indicate that isolated VEGF-C expression by malignant cells is not of predictive value for occult lymph-node metastasis in the early stages of OSCC.
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This study investigated if tumor-associated tissue eosinophilia (TATE) could be associated with the process of tissue invasion in oral squamous cell carcinomas (OSCCs) and its influence on patient`s prognosis. Forty-three patients treated for OSCCs with or without lymph nodes involvement, at A. C. Camargo Cancer Hospital, Brazil, were selected for TATE analysis. Two degrees of tissue eosinophilia were established in OSCC: absent/mild and intense. The TATE was evaluated in relation to the clinicopathological features and prognostic value using chi(2) test and the Kaplan-Meier method. Most of the patients with OSCC in advanced clinical stage presented Muscular infiltration and significantly intense TATE whereas those with tumors in early stage frequently showed absent/mild eosinophilia (P = .009). The TATE showed no prognostic value for 5-year and 10-year survival rates of the OSCC. These findings suggest that intense TATE seems to reflect the stromal invasion of the OSCCs that occur in advanced clinical stage.
Resumo:
A utilização da madeira de eucalipto na confecção de painéis MDF é recente, tornando-se necessário entender as modificações em sua estrutura anatômica durante as etapas do processo industrial, notadamente no desfibramento dos cavacos. Com esse objetivo, neste estudo foram aplicadas três condições diferenciadas de desfibramento dos cavacos, alterando-se (i) o tempo de aquecimento, (ii) as pressões de digestão e de desfibramento e (iii) a energia específica de desfibramento, sendo avaliadas as características anatômicas dos componentes celulares da madeira. O aumento da intensidade de refino dos cavacos de madeira reduziu o comprimento médio das fibras e aumentou o porcentual de fibras quebradas, corroborando as imagens de microscopia eletrônica de varredura, além da diminuição do número dos vasos e de células de parênquima. Essa condição de desfibramento mais intensa promoveu, também, um característico escurecimento da coloração da polpa composta pelos elementos celulares da madeira. A aplicação de variáveis de desfibramento mais brandas aumentou a presença de feixes de fibras e do número de vasos e de parênquima, resultando em uma polpa de coloração mais clara. As alterações das características morfológicas dos componentes celulares da madeira dos cavacos de eucalipto, após o tratamento de desfibramento, relacionaram-se com as etapas do processo operacional e com a qualidade tecnológica dos painéis de fibras MDF.
Resumo:
Objetivou-se neste trabalho avaliar a variação das dimensões das fibras e dos vasos da madeira de Eucalyptus grandis com quatro diferentes idades (10, 14, 20 e 25 anos), proveniente de talhões comerciais. A amostragem do material na árvore foi feita através da coleta de três discos, retirados da base e das extremidades das duas primeiras toras, ambas com o comprimento comercial de 3 m. De cada disco, retiraram-se cinco amostras, de dimensões 1,0 x 1,0 x 1,0 cm, tomadas de pontos eqüidistantes, correspondentes a 0; 25; 50; 75; e 100% da seção, no sentido radial medula-casca, fazendo-se a medição das fibras e dos vasos. Verificou-se, em todos os parâmetros, o efeito da idade e da variação radial, no sentido medula-casca, à exceção da largura e do diâmetro do lume das fibras; todos os demais parâmetros apresentaram correlação positiva.
Resumo:
A resistência natural ao apodrecimento se constitui numa importante propriedade da madeira. Em se tratando das madeiras provenientes do gênero Eucalyptus, tal atributo se torna ainda mais importante, uma vez que tais madeiras são, na grande maioria das vezes, de difícil tratabilidade pelos métodos de tratamento convencionais. O objetivo do presente trabalho foi determinar a resistência natural da madeira de sete espécies de eucalipto em ensaio acelerado de laboratório ao fungo causador da podridão-parda Gloeophyllum trabeum. Foram ensaiadas madeiras das espécies de Corymbia citriodora, Eucalyptus tereticornis, E. paniculata, E. pilularis, E. cloeziana, E. urophylla e E. grandis com 16 anos de idade, que cresceram na Estação Experimental de Anhembi, em São Paulo, pertencente ao Departamento de Ciências Florestais da ESALQ/USP. No que diz respeito ao apodrecimento causado pelo fungo Gloeophyllum trabeum, a madeira de eucalipto das sete espécies pode ser considerada resistente, uma vez que os valores de perda de massa foram sempre inferiores a 10%.
Resumo:
As variações de umidade e da densidade do lenho das árvores são as principais causas dos defeitos de secagem, como o empenamento e fendilhamento das peças de madeira. Os tipos de madeira presentes em um tronco estão relacionados com as variações dessas duas importantes propriedades físicas. Os gradientes de umidade e da densidade da madeira de sete espécies de eucalipto foram avaliados nas direções radial e longitudinal do tronco de árvores recém-abatidas. Os resultados apontaram uma maior homogeneidade de distribuição de umidade dentro das árvores de E. paniculata e E. citriodora, indicada pelos coeficientes de variação e desvio-padrão. O diferencial de umidade da madeira nas regiões internas do tronco de E. paniculata e E. citriodora foi de 20% e de E. urophylla e E. grandis, de 80%. A densidade básica da madeira aumentou na direção radial do tronco, e cada espécie de eucalipto apresentou um modelo de variação.
Resumo:
Myocardial infarction leads to compensatory ventricular remodeling. Disturbances in myocardial contractility depend on the active transport of Ca2+ and Na+, which are regulated by Na+-K+ ATPase. Inappropriate regulation of Na+-K+ ATPase activity leads to excessive loss of K+ and gain of Na+ by the cell. We determined the participation of Na+-K+ ATPase in ventricular performance early and late after myocardial infarction. Wistar rats (8-10 per group) underwent left coronary artery ligation (infarcted, Inf) or sham-operation (Sham). Ventricular performance was measured at 3 and 30 days after surgery using the Langendorff technique. Left ventricular systolic pressure was obtained under different ventricular diastolic pressures and increased extracellular Ca2+ concentrations (Ca2+e) and after low and high ouabain concentrations. The baseline coronary perfusion pressure increased 3 days after myocardial infarction and normalized by 30 days (Sham 3 = 88 ± 6; Inf 3 = 130 ± 9; Inf 30 = 92 ± 7 mmHg; P < 0.05). The inotropic response to Ca2+e and ouabain was reduced at 3 and 30 days after myocardial infarction (Ca2+ = 1.25 mM; Sham 3 = 70 ± 3; Inf 3 = 45 ± 2; Inf 30 = 29 ± 3 mmHg; P < 0.05), while the Frank-Starling mechanism was preserved. At 3 and 30 days after myocardial infarction, ventricular Na+-K+ ATPase activity and contractility were reduced. This Na+-K+ ATPase hypoactivity may modify the Na+, K+ and Ca2+ transport across the sarcolemma resulting in ventricular dysfunction.