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1.
Int J Biol Macromol ; 127: 169-177, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30639656

RESUMO

Pullulan is a biopolymer used in food industry produced by Aureobasidium pullulans from starch. In the present work, sugarcane bagasse (SCB) hydrolysate was evaluated as an alternative substrate in fermentation process assisted by blue LED lights. The best fermentation conditions in Erlenmeyer flasks were 25.3 °C, stirring speed of 232 rpm and yeast extract concentration of 1.88 g/L, yielding 25.19 g/L of pullulan, that corresponded to yield of 0.48 g/g and 0.28 g/(L·h) of volumetric productivity. By using a column bubble photobioreactor, similar yield values were obtained. Thermal properties of the produced pullulan as glass transition (Tg) and melting (Tm) temperatures were 38 °C and 160 °C, respectively, which were similar to the corresponding values of commercial food grade pullulan. Therefore, SCB hydrolysate is a promising substrate to produce good quality pullulan (86% of purity) with application in food industry, besides to represent a new alternative for biorefineries.


Assuntos
Ascomicetos/crescimento & desenvolvimento , Celulose/química , Glucanos , Saccharum/química , Glucanos/biossíntese , Glucanos/química , Glucanos/isolamento & purificação
2.
J Anim Physiol Anim Nutr (Berl) ; 100(3): 513-9, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26613801

RESUMO

The aim of this study was to evaluate the effects of oral creatine supplementation on the athletic performance of equines used for barrel racing. Ten healthy Quarter Horses, or Quarter Horse crossbred, weighing 429.7 ± 25.3 kg and with mean age of 3.8 ± 1.2 years, were used. Animals were evaluated in four different moments (M1, M2, M3, M4), and between M3 and M4, they were supplemented with 28 g of creatine/100 kg of body weight, orally, for 45 days. Although significant alterations for LDH activity, plasma glucose and packed cell volume were observed, it was possible to conclude that there was no improvement in the athletic performance for the animals used on the experiment, as there were no changes in time scores, heart rate and plasma lactate, variables considered as performance indicators, before and after supplementation.


Assuntos
Creatina/farmacologia , Cavalos/fisiologia , Condicionamento Físico Animal/fisiologia , Esportes , Administração Oral , Animais , Creatina/administração & dosagem , Feminino , Masculino
3.
Sci Total Environ ; 468-469: 12-8, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24012891

RESUMO

Radon levels in two old mines in San Luis, Argentina, were measured and analyzed, with the aim to assess the potential use of this radioactive noble gas as a tracer of geological processes in underground environments. La Carolina gold mine and Los Cóndores tungsten mine are today used as tourism mines. CR-39 nuclear track detectors were used for this purpose. Measurements were performed during both winter and summer seasons. The findings show that in these environments, significant radon concentrations are subject to large seasonal fluctuations, due to the strong dependence on natural ventilation with the outside temperature variations. For both mines, higher concentration values of (222)Rn were observed in summer than in winter; with an extreme ratio of 2.5 times between summer and winter seasons for Los Cóndores mine. The pattern of radon transport inside La Carolina mine revealed, contrary to what was believed, that this mine behaves as a system with two entrances located at different levels. However, this feature can only be observed in the winter season, when there is a marked difference between the inside and outside temperatures of the mine. In the case of Los Cóndores mine, the radon concentration pattern distribution is principally established by air current due to chimney-effect in summer and winter seasons. In both cases, the analyses of radon pattern distribution appear as a good method to trace air currents, and then localize unknown ducts, fissures or secondary tunnels in subterranean environments.


Assuntos
Monitoramento Ambiental/métodos , Mineração , Traçadores Radioativos , Radônio/análise , Movimentos do Ar , Argentina , Polietilenoglicóis , Estações do Ano , Temperatura
4.
Rev. bras. plantas med ; 16(2): 262-270, jun. 2014. graf, tab
Artigo em Português | LILACS | ID: lil-711786

RESUMO

A erva-baleeira, espécie medicinal anti-inflamatória, pode ser propagada por sementes, no entanto, o desenvolvimento de métodos eficientes para a propagação vegetativa possibilitará a uniformidade nas populações e a clonagem de plantas de interesse quanto aos aspectos agronômico e de composição química. O presente trabalho objetivou avaliar os efeitos do ácido naftaleno acético (NAA) e do ácido indolbutírico (IBA) e de diferentes substratos no enraizamento de estacas semi-lenhosas de erva-baleeira. Os experimentos foram conduzidos em casa de vegetação em Montes Claros em delineamento inteiramente casualizados. Para o experimento teste da influência das auxinas, as estacas foram submetidas a tratamentos com NAA e IBA nas concentrações de 0, 500, 1000, 2000, 3000 e 4000 mg L-1, e para o experimento dos substratos, cinco substratos foram avaliados (vermiculita expandida + casca de arroz parcialmente carbonizada (proporção de 1:1); vermiculita expandida; substrato orgânico comercial para hortaliça (Tropstrato HT ®); areia; solo + compostagem (proporção de 1:1)). Após 90 dias, para ambos os experimentos, foram avaliadas porcentagem de estacas enraizadas, de estacas mortas, de estacas vivas com calos, de estacas mortas com calos, número de raízes formadas por estaca e comprimento das três maiores raízes (cm). O regulador vegetal ideal para o enraizamento da espécie é o IBA, na concentração de 2.000 mg L-1, sendo que o NAA não é recomendado para a indução radicial em estacas erva-baleeira. O substrato vermiculita com casca de arroz carbonizada na proporção de 1:1 proporcionou maior porcentagem de enraizamento nas estacas da erva-baleira que o substrato solo + compostagem (1:1), os demais substratos não diferenciaram entre si.


The Varronia curassavica Jacq., black sage, is an anti-inflammatory medicinal species that can be propagated by seed; however, the development of efficient methods for vegetative propagation will enable uniformity in the populations and cloning of plants of interest regarding the agronomic aspects and chemical composition. The aim of this study was to assess the effects of the naphthalene acetic acid (NAA) and indole butyric acid (IBA) and different substrates on the rooting of semi-hardwood cuttings of black sage. The experiments were conducted in a greenhouse at Montes Claros, in the State of Minas Gerais, Brazil, as a randomized complete design. For the experiment to test the influence of auxin, the cuttings were subjected to treatments with NAA and IBA at the concentrations of 0, 500, 1000, 2000, 3000 and 4000 mg L-1, and for the experiment with substrates, five substrates were evaluated (expanded vermiculite + carbonized rice husk (1:1); expanded vermiculite; commercial organic substrate for vegetable (Tropstrato ® HT); sand; soil + compost (1:1)). After 90 days, in both experiments, we evaluated the rooting percentage of cuttings, dead cuttings, live cuttings with callus, dead cuttings with callus, number of roots per cutting and length of the three longest roots (cm). The best plant growth regulator for the rooting of the species is the IBA at a concentration of 2.000 mg L-1, and the NAA is not recommended for the induction of roots in cuttings of black sage. Vermiculite with carbonized rice husk in the ratio of 1:1 showed greater percentage of rooting in cuttings of black sage than soil + composting (1:1); other substrates did not differ among themselves.


Assuntos
Substratos para Tratamento Biológico/classificação , Cordia/metabolismo , Reguladores de Crescimento de Plantas , Plantas Medicinais/classificação
5.
J Environ Radioact ; 102(11): 1055-61, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21729819

RESUMO

Health hazard from natural radioactivity in Brazilian granites, covering the walls and floor in a typical dwelling room, was assessed by indirect methods to predict external gamma-ray dose rates and radon concentrations. The gamma-ray dose rate was estimated by a Monte Carlo simulation method and validated by in-situ measurements with a NaI spectrometer. Activity concentrations of (232)Th, (226)Ra, and (40)K in an extensive selection of Brazilian commercial granite samples measured by using gamma-ray spectrometry were found to be 4.5-450 Bq kg(-1), 4.9-160 Bq kg(-1) and 190-2029 Bq kg(-1), respectively. The maximum external gamma-ray dose rate from floor and walls covered with the Brazilian granites in the typical dwelling room (5.0 m × 4.0 m area, 2.8 m height) was found to be 120 nGy h(-1), which is comparable with the average worldwide exposure to external terrestrial radiation of 80 nGy h(-1) due to natural sources, proposed by United Nations Scientific Committee on the Effects of Atomic Radiation. Radon concentrations in the room were also estimated by a simple mass balance equation and exhalation rates calculated from the measured values of (226)Ra concentrations and the material properties. The results showed that the radon concentration in the room ventilated adequately (0.5 h(-1)) will be lower than 100 Bq m(-3), value recommended as a reference level by the World Health Organization.


Assuntos
Contaminação Radioativa do Ar/análise , Materiais de Construção , Raios gama , Radônio/análise , Poluentes Radioativos do Solo/análise , Brasil , Simulação por Computador , Humanos , Exposição por Inalação/análise , Método de Monte Carlo , Doses de Radiação , Medição de Risco/métodos
6.
Electromyogr Clin Neurophysiol ; 49(6-7): 305-10, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19845103

RESUMO

The objective of this study is to verify the coincidence between the occurrence of the electromyographic fatigue threshold (EMGth) and the ventilatory threshold (Vth) in an incremental test in the cyclosimulator, as well as to compare the calculation of the RMS from the EMG signal using different time windows. Thirteen male cyclists (73.7 +/- 12.4 kg and 174.3 +/- 6.2 cm) performed a ramp incremental test (TI) in a cyclosimulator until voluntary exhaustion. Before the start of each TI subjects had the active bipolar electrodes placed over the superficial muscles of the quadriceps femoris (QF) of the right leg: rectus femoris (RF), vastus medialis (VM) and vastus lateralis (VL). The paired student's t test, pearson's correlation coefficient and the analysis method described by Bland and Altman for the determination of the concordance level were used for statistical analysis. The significance level adopted was P < 0.05. Although no significant differences were found between Vth and the EMGth calculated from windows of 2, 5, 10, 30 and 60 seconds in the studied muscles, it is suggested that the EMGth values determined from the calculation of the RMS curve with windows of 5 and 10 seconds seem to be more appropriate for the calculation of the RMS curve and determination of EMGth from visual inspection.


Assuntos
Limiar Anaeróbio/fisiologia , Eletromiografia/métodos , Fadiga Muscular/fisiologia , Músculo Esquelético/fisiologia , Adulto , Análise de Variância , Ciclismo/fisiologia , Índice de Massa Corporal , Teste de Esforço , Humanos , Masculino
7.
Clin Lab Haematol ; 28(2): 126-9, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16630218

RESUMO

Acute promyelocytic leukemia (APL) is characterized by the presence of rearrangements involving the retinoic acid receptor alpha (RARalpha) gene and a variable incidence in different populations. The hybrid gene PML-RARalpha, present in 98% of cases, encodes a fusion protein essential to the pathogenesis of the disease. Depending of the PML's gene breakpoint in chromosome 15, the transcript subtypes bcr1, bcr2 and bcr3 may be formed. The correlation between these transcript subtypes and clinical parameters is still controversial. The objective of this study was to determine the frequencies of the PML-RARalpha transcripts and subtypes in a series of 32 APL patients from Northeast Brazil and to evaluate the association of these subtypes to different parameters. The method used was RT-PCR. The frequency of our APL cases is approximately 28% of the acute leukemias. The results showed the presence of PML-RARalpha isoform in all patients and a higher frequency of the bcr1/2 subtype. No significant statistical association was found between molecular subtypes and age, sex, French-American-British (FAB) classification, leukocyte and platelet count, hemoglobin level or coagulation tests. In conclusion, these data suggest similar molecular and biological features for our APL patients at diagnosis in comparison with those reported in current scientific literature.


Assuntos
Leucemia Promielocítica Aguda/genética , Proteínas de Neoplasias/genética , Proteínas de Fusão Oncogênica/genética , Adolescente , Adulto , Brasil , Criança , Feminino , Hemoglobinas/metabolismo , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/sangue , Proteínas de Fusão Oncogênica/sangue , Contagem de Plaquetas , Isoformas de Proteínas/sangue , Isoformas de Proteínas/genética , Proteínas Proto-Oncogênicas c-bcr/genética
8.
Hig. aliment ; 15(88): 71-6, set. 2001. tab, graf
Artigo em Português | LILACS | ID: lil-298833

RESUMO

Foram investigadas as possíveis alteraçöes da qualidade do iogurte natural de duas marcas com maior vendagem. Dois experimentos foram delineados. No primeiro experimento as amostras foram mantidas sob refrigeraçäo a 5§C e 8§C. A avaliaçäo foi realizada em amostras dentro da 4ª semana de validade e aos 7 e 15 dias após o vencimento da validade. No segundo experimento, as amostras foram coletadas em quatro pontos de distribuiçäo e avaliadas dentro da terceira semana da validade, totalizando 11 amostras para cada marca. Nos dois experimentos, foram avaliadas as populaçöes de coliformes totais e fecais e de bactérias láticas totais. Também avaliadas as variaçöes de pH e acidez titulável, expressa em porcentagem de ácido lático. No primeiro experimento observou-se que independentemente da marca e, dentro do prazo de validade (4ª semana) näo houve variaçäo significativa de pH e da acidez total, os quais mantiveram-se entre 3,9 e 4,5 e 0,7 e 0,9 por cento respectivamente, valores estes considerados normais para o iogurte natural. Quanto à populaçäo de bactérias láticas, observou-se que as proporçöes de cultura lática empregadas difere de um fabricante para outro, sendo que a marca 2 apresentou maior número de bactérias láticas totais e portanto, maior acidez titulável. Isto levou no teste sensorial a uma maior aceitaçäo pelo produto da marca 1, com menor número de bactérias láticas e menor acidez. No segundo experimento, embora a temperatura de armazenamento tenha variado entre os pontos de distribuiçäo (até 17§C), näo foram observadas alteraçöes significativas na qualidade dos produtos.


Assuntos
Laticínios/microbiologia , Qualidade dos Alimentos , Laticínios/análise
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