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Id: biblio-951810
Autor: Rungrattanakasin, Budsayachat; Premjet, Siripong; Thanonkeo, Sudarat; Klanrit, Preekamol; Thanonkeo, Pornthap.
Título: Cloning and expression of an endoglucanase gene from the thermotolerant fungus Aspergillus fumigatus DBiNU-1 in Kluyveromyces lactis
Fonte: Braz. j. microbiol;49(3):647-655, July-Sept. 2018. graf.
Idioma: en.
Resumo: Abstract An intronless endoglucanase from thermotolerant Aspergillus fumigatus DBINU-1 was cloned, characterized and expressed in the yeast Kluyveromyces lactis. The full-length open reading frame of the endoglucanase gene from A. fumigatus DBiNU-1, designated Cel7, was 1383 nucleotides in length and encoded a protein of 460 amino acid residues. The predicted molecular weight and the isoelectric point of the A. fumigatus Cel7 gene product were 48.19 kDa and 5.03, respectively. A catalytic domain in the N-terminal region and a fungal type cellulose-binding domain/module in the C-terminal region were detected in the predicted polypeptide sequences. Furthermore, a signal peptide with 20 amino acid residues at the N-terminus was also detected in the deduced amino acid sequences of the endoglucanase from A. fumigatus DBiNU-1. The endoglucanase from A. fumigatus DBiNU-1 was successfully expressed in K. lactis, and the purified recombinant enzyme exhibited its maximum activity at pH 5.0 and 60 °C. The enzyme was very stable in a pH range from 4.0 to 8.0 and a temperature range from 30 to 60 °C. These features make it suitable for application in the paper, biofuel, and other chemical production industries that use cellulosic materials.
Descritores: Aspergillus fumigatus/enzimologia
Proteínas Fúngicas/genética
Proteínas Fúngicas/química
Expressão Gênica
Celulase/genética
Celulase/química
Clonagem Molecular
-Aspergillus fumigatus/genética
Especificidade por Substrato
Estabilidade Enzimática
Kluyveromyces/genética
Kluyveromyces/metabolismo
Proteínas Recombinantes/genética
Proteínas Recombinantes/metabolismo
Proteínas Recombinantes/química
Proteínas Fúngicas/metabolismo
Celulase/metabolismo
Temperatura Alta
Concentração de Íons de Hidrogênio
Responsável: BR1.1 - BIREME


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Id: biblio-837953
Autor: Salvio, Ana Gabriela; Nunes, Adauto Jose; Angarita, Dora Patricia Ramirez.
Título: Laptop computer induced erythema ab igne: a new presentation of an old disease
Fonte: An. bras. dermatol;91(5,supl.1):79-80, Sept.-Oct. 2016. graf.
Idioma: en.
Resumo: Abstract Erythema ab igne is a condition characterized by skin changes due to chronic exposure to moderate temperature. We describe a female patient with continuous use of a laptop computer on exposed legs for 6 months and consequent development of reticulated hyperpigmentation at the area. Histopathological examination revealed epidermal atrophy, collagen fragmentation, and vacuolar changes in the basal layer, among other signs. We consider this case to be a modern cause of erythema ab igne.
Descritores: Microcomputadores
Hiperpigmentação/etiologia
Hiperpigmentação/patologia
Eritema/etiologia
Eritema/patologia
Temperatura Alta/efeitos adversos
-Epiderme/patologia
Limites: Seres Humanos
Feminino
Meia-Idade
Tipo de Publ: Relatos de Casos
Responsável: BR1.1 - BIREME


  3 / 473 LILACS  
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Id: biblio-839372
Autor: Mejía-Barajas, Jorge A; Montoya-Pérez, Rocío; Salgado-Garciglia, Rafael; Aguilera-Aguirre, Leopoldo; Cortés-Rojo, Christian; Mejía-Zepeda, Ricardo; Arellano-Plaza, Melchor; Saavedra-Molina, Alfredo.
Título: Oxidative stress and antioxidant response in a thermotolerant yeast
Fonte: Braz. j. microbiol;48(2):326-332, April.-June 2017. tab, graf.
Idioma: en.
Resumo: Abstract Stress tolerance is a key attribute that must be considered when using yeast cells for industrial applications. High temperature is one factor that can cause stress in yeast. High environmental temperature in particular may exert a natural selection pressure to evolve yeasts into thermotolerant strains. In the present study, three yeasts (Saccharomyces cerevisiae, MC4, and Kluyveromyces marxianus, OFF1 and SLP1) isolated from hot environments were exposed to increased temperatures and were then compared with a laboratory yeast strain. Their resistance to high temperature, oxidative stress, and antioxidant response were evaluated, along with the fatty acid composition of their cell membranes. The SLP1 strain showed a higher specific growth rate, biomass yield, and biomass volumetric productivity while also showing lower duplication time, reactive oxygen species (ROS) production, and lipid peroxidation. In addition, the SLP1 strain demonstrated more catalase activity after temperature was increased, and this strain also showed membranes enriched in saturated fatty acids. It is concluded that the SLP1 yeast strain is a thermotolerant yeast with less oxidative stress and a greater antioxidant response. Therefore, this strain could be used for fermentation at high temperatures.
Descritores: Saccharomyces cerevisiae/fisiologia
Estresse Fisiológico
Kluyveromyces/fisiologia
Estresse Oxidativo
Antioxidantes/metabolismo
-Saccharomyces cerevisiae/crescimento & desenvolvimento
Saccharomyces cerevisiae/efeitos da radiação
Saccharomyces cerevisiae/química
Kluyveromyces/crescimento & desenvolvimento
Kluyveromyces/efeitos da radiação
Kluyveromyces/química
Peroxidação de Lipídeos
Catalase/análise
Membrana Celular/química
Espécies Reativas de Oxigênio/metabolismo
Biomassa
Ácidos Graxos/análise
Temperatura Alta
Responsável: BR1.1 - BIREME


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Id: lil-623599
Autor: Soares, C. M. A; Urmenyi, T. P; Ferreira, C. S; Carvalho, E. F. de; Carvalho, J. F. O; Rondinelli, E; Castro, F. T. de.
Título: Thermal and developmental regulation of gene expression in Trypanosoma cruzi
Fonte: Mem. Inst. Oswaldo Cruz;83(supl.1):337-344, Nov. 1988. ilus.
Idioma: en.
Conferência: Apresentado em: Annual Meeting on Basic Research in Chagas's disease, 15, Apresentado em: Meeting of the Brazilian Society of Protozoology4, Caxambu, 7-10 Nov. 1988.
Descritores: Trypanosoma cruzi/genética
Tubulina (Proteína)/uso terapêutico
-Regulação da Expressão Gênica
Temperatura Alta
Responsável: BR1.1 - BIREME


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Id: lil-777218
Autor: SANT’ANNA JUNIOR, Arnaldo; GUERREIRO-TANOMARU, Juliane Maria; MARTELO, Roberta Bosso; SILVA, Guilherme Ferreira da; TANOMARU FILHO, Mário.
Título: Filling of simulated lateral canals with gutta-percha or thermoplastic polymer by warm vertical compaction
Fonte: Braz. oral res. (Online);29(1):1-6, 2015. tab, ilus.
Idioma: en.
Projeto: Fundação de Amparo à Pesquisa do Estado de São Paulo.
Resumo: The aim of this study was to evaluate the ability of gutta-percha and a thermoplastic synthetic polymer (Resilon) to fill simulated lateral canals, using warm vertical compaction. Forty-five single-rooted human teeth were prepared using the rotary crown-down technique. Artificial lateral canals were made at 2, 5, and 8 mm from the working length (WL) in each root. The specimens were divided into three groups (n = 15), according to the filling material: Dentsply gutta-percha (GD), Odous gutta-percha (GO), and Resilon cones (RE). The root canals were obturated using warm vertical compaction, without endodontic sealer. The specimens were subjected to a tooth decalcification and clearing procedure. Filling of the lateral canals was analyzed by digital radiography and digital photographs, using the Image Tool software. The data were subjected to the Kruskal-Wallis and Dunn tests at 5% significance. RE had the best filling ability in all root thirds (p < 0.05), with similar results for GO in the coronal third. In the middle and apical thirds, GD and GO had similar results (p > 0.05). Resilon may be used as an alternative to gutta-percha as a solid core filling material for use with the warm vertical compaction technique. The study findings point to the potential benefit of the warm vertical compaction technique for filling lateral canals, and the study provides further information about using Resilon and gutta-percha as materials for the warm vertical compaction technique.
Descritores: Polímeros/química
Materiais Restauradores do Canal Radicular/química
Obturação do Canal Radicular/métodos
Guta-Percha/química
-Obturação do Canal Radicular/instrumentação
Teste de Materiais
Reprodutibilidade dos Testes
Estatísticas não Paramétricas
Radiografia Dentária Digital
Temperatura Alta
Limites: Seres Humanos
Tipo de Publ: Research Support, Non-U.S. Gov't
Estudos de Avaliação
Responsável: BR1.1 - BIREME


  6 / 473 LILACS  
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Id: biblio-1021034
Autor: Mihálik, Daniel; Gubisová, Marcela; Kraic, Ján; Hudcovicová, Martina; Havrlentová, Michaela; Moravcíková, Jana; Glasa, Miroslav; Matusíková, Ildikó.
Título: Introduction of a synthetic Thermococcus-derived α-amlyase gene into barley genome for increased enzyme thermostability in grains
Fonte: Electron. j. biotechnol;30:1-5, nov. 2017. ilus, tab, graf.
Idioma: en.
Projeto: Slovak Research and Development Agency.
Resumo: Background: The enzymes utilized in the process of beer production are generally sensitive to higher temperatures. About 60% of them are deactivated in drying the malt that limits the utilization of starting material in the fermentation process. Gene transfer from thermophilic bacteria is a promising tool for producing barley grains harboring thermotolerant enzymes. Results: Gene for α-amylase from hydrothermal Thermococcus, optimally active at 75­85°C and pH between 5.0 and 5.5, was adapted in silico to barley codon usage. The corresponding sequence was put under control of the endosperm-specific promoter 1Dx5 and after synthesis and cloning transferred into barley by biolistics. In addition to model cultivar Golden Promise we transformed three Slovak barley cultivars Pribina, Levan and Nitran, and transgenic plants were obtained. Expression of the ~50 kDa active recombinant enzyme in grains of cvs. Pribina and Nitran resulted in retaining up to 9.39% of enzyme activity upon heating to 75°C, which is more than 4 times higher compared to non-transgenic controls. In the model cv. Golden Promise the grain α-amylase activity upon heating was above 9% either, however, the effects of the introduced enzyme were less pronounced (only 1.22 fold difference compared with non-transgenic barley). Conclusions: Expression of the synthetic gene in barley enhanced the residual α-amylase activity in grains at high temperatures.
Descritores: Sementes/enzimologia
Hordeum/enzimologia
Thermococcus/metabolismo
alfa-Amilases/metabolismo
-Sementes/genética
Sementes/microbiologia
Transformação Genética
Hordeum/genética
Hordeum/microbiologia
Cerveja
Estabilidade Enzimática
Plantas Geneticamente Modificadas/enzimologia
Clonagem Molecular
Técnicas de Transferência de Genes
alfa-Amilases/genética
Fermentação
Termotolerância
Temperatura Alta
Concentração de Íons de Hidrogênio
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-1008708
Autor: Valdebenito-Rolack, Emky; Ruiz-Tagle, Nathaly; Abarzúa, Leslie; Aroca, Germán; Urrutia, Homero.
Título: Characterization of a hyperthermophilic sulphur-oxidizing biofilm produced by archaea isolated from a hot spring
Fonte: Electron. j. biotechnol;25:58-63, ene. 2017. tab, graf, ilus.
Idioma: en.
Projeto: FONDECYT.
Resumo: Background: Sulphur-oxidizing microorganisms are widely used in the biofiltration of total reduced sulphur compounds (odorous and neurotoxic) produced by industries such as the cellulose and petrochemical industries, which include high-temperature process steps. Some hyperthermophilic microorganisms have the capability to oxidize these compounds at high temperatures (N60°C), and archaea of this group, for example, Sulfolobus metallicus, are commonly used in biofiltration technology. Results: In this study, a hyperthermophilic sulphur-oxidizing strain of archaea was isolated from a hot spring (Chillán, Chile) and designated as M1. It was identified as archaea of the genus Sulfolobus (99% homology with S. solfataricus 16S rDNA). Biofilms of this culture grown on polyethylene rings showed an elemental sulphur oxidation rate of 95.15 ± 15.39 mg S l-1 d-1, higher than the rate exhibited by the biofilm of the sulphur-oxidizing archaea S. metallicus (56.8 ± 10.91 mg l-1 d-1). Conclusions: The results suggest that the culture M1 is useful for the biofiltration of total reduced sulphur gases at high temperatures and for other biotechnological applications.
Descritores: Sulfetos/metabolismo
Archaea/metabolismo
Biofilmes
-Oxirredução
Filogenia
Reação em Cadeia da Polimerase
Sulfolobus
Archaea/isolamento & purificação
Archaea/genética
Polietileno
Fontes Termais/microbiologia
Eletroforese
Filtração
Extremófilos
Temperatura Alta
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-1008576
Autor: Deng, Nan; Liu, Caixia; Chang, Ermei; Ji, Jing; Yao, Xiamei; Yue, Jianyun; Bartish, Igor V; Chen, Lanzhen; Jiang, Zeping; Shi, Shengqing.
Título: High temperature and UV-C treatments affect stilbenoid accumulation and related gene expression levels in Gnetum parvifolium
Fonte: Electron. j. biotechnol;25:43-49, ene. 2017. ilus, tab, graf.
Idioma: en.
Projeto: State Key Laboratory of Tree Genetics and Breeding; . 948 project; . Fund of National Non-profit Research Institutions of CAF.
Resumo: Background: Gnetum parvifolium stems and roots have been used for a long time in traditional Chinese medicines. Stilbenes are bioactive compounds present in G. parvifolium plants, and they possess antioxidative and anticancer properties. However, little is known about the responses of G. parvifolium stilbene biosynthetic pathways to stress conditions. Therefore, we investigated stilbene biosynthesis, including the expression of relevant genes, in G. parvifolium exposed to high-temperature and ultraviolet-C treatments. Results: High temperatures did not influence the accumulation of total stilbenes in stems but decreased stilbene concentrations in roots at 3 h, with a subsequent restoration to control levels. In contrast, ultraviolet irradiation induced the accumulation of total stilbenes in stems but not in roots. We also observed that high temperatures inhibited the production of resveratrol and piceatannol in G. parvifolium stems and roots, whereas ultraviolet treatments initially inhibited their accumulation (up to 6 h) but induced their production at later time points. Analyses of specific genes (i.e., PAL, C4H, 4CL, STS, and CYP) revealed that their expression levels generally increased in stress-treated stems and roots, although there was some variability in the expression profiles during treatments. Conclusions: Our results indicated that high temperatures and ultraviolet irradiation differentially affect the biosynthesis of specific stilbenes in G. parvifolium stems and roots. Therefore, cultivating G. parvifolium seedlings under optimal stress conditions may increase the biosynthesis of specific stilbene compounds.
Descritores: Estilbenos/análise
Gnetum/metabolismo
-Estilbenos/efeitos da radiação
Estilbenos/metabolismo
Raios Ultravioleta
Reação em Cadeia da Polimerase Via Transcriptase Reversa
Gnetum/efeitos da radiação
Gnetum/genética
Plântulas
Polifenóis/análise
Polifenóis/efeitos da radiação
Polifenóis/metabolismo
CHLOROFLUOROCARBONS, METHANE1
Temperatura Alta
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-895557
Autor: Borges, Karen A; Furian, Thales Q; Souza, Sara N; Menezes, Rafaela; Tondo, Eduardo C; Salle, Carlos T. P; Moraes, Hamilton L. S; Nascimento, Vladimir P.
Título: Biofilm formation capacity of Salmonella serotypes at different temperature conditions / Capacidade de produção de biofilme por cepas de diferentes sorovares de Salmonella em quatro temperaturas de incubação
Fonte: Pesqui. vet. bras = Braz. j. vet. res;38(1):71-76, Jan. 2018. tab.
Idioma: en.
Projeto: CNPq.
Resumo: Salmonella spp. are one of the most important agents of foodborne disease in several countries, including Brazil. Poultry-derived products are the most common food products, including meat and eggs, involved in outbreaks of human salmonellosis. Salmonella has the capacity to form biofilms on both biotic and abiotic surfaces. The biofilm formation process depends on an interaction among bacterial cells, the attachment surface and environmental conditions. These structures favor bacterial survival in hostile environments, such as slaughterhouses and food processing plants. Biofilms are also a major problem for public health because breakage of these structures can cause the release of pathogenic microorganisms and, consequently, product contamination. The aim of this study was to determine the biofilm production capacity of Salmonella serotypes at four different temperatures of incubation. Salmonella strains belonging to 11 different serotypes, isolated from poultry or from food involved in salmonellosis outbreaks, were selected for this study. Biofilm formation was investigated under different temperature conditions (37°, 28°, 12° and 3°C) using a microtiter plate assay. The tested temperatures are important for the Salmonella life cycle and to the poultry-products process. A total of 92.2% of the analyzed strains were able to produce biofilm on at least one of the tested temperatures. In the testing, 71.6% of the strains produced biofilm at 37°C, 63% at 28°C, 52.3% at 12°C and 39.5% at 3°C, regardless of the serotype. The results indicate that there is a strong influence of temperature on biofilm production, especially for some serotypes, such as S. Enteritidis, S. Hadar and S. Heidelberg. The production of these structures is partially associated with serotype. There were also significant differences within strains of the same serotype, indicating that biofilm production capacity may be strain-dependent.(AU)

Salmonella spp. são um dos mais importantes agentes causadores de doenças transmitidas por alimentos em vários países, inclusive no Brasil. Produtos avícolas e ovos são os principais alimentos envolvidos na transmissão dos sorovares de Salmonella que são responsáveis por surtos de salmonelose em humanos. Salmonella possui a capacidade de formar biofilmes em diversas superfícies. O processo de formação de biofilme depende da interação entre as células bacterianas, a superfície de adesão e as condições do ambiente onde a bactéria se encontra. Estas estruturas favorecem a sobrevivência bacteriana em ambientes hostis, como em matadouros-frigoríficos e em indústrias processadoras de alimentos. Biofilmes são um grande problema em saúde pública, pois a ruptura destas estruturas pode provocar a liberação de microrganismos patogênicos e, consequentemente, a contaminação dos produtos. O objetivo deste estudo foi avaliar a capacidade de produção de biofilme por diferentes sorovares de Salmonella submetidos a quatro temperaturas de incubação. Cepas de Salmonella de 11 sorovares foram selecionadas. A produção de biofilme foi avaliada através do método de incubação em microplacas de poliestireno incubadas a 37°, 28°, 12° e 3°C. Estas temperaturas são importantes durante o ciclo de vida de Salmonella e para o processamento de produtos avícolas. Do total de cepas avaliadas, 92,2% foram capazes de produzir biofilme em pelo menos uma das quatro temperaturas testadas. Neste estudo, 71,6% das cepas produziram biofilme a 37°C, 63% a 28°C, 52,3% a 12°C e 39,5% a 3°C, independentemente do sorovar. Os resultados indicam uma forte influência da temperatura na produção de biofilme, especialmente para os sorovares S. Enteritidis, S. Hadar e S. Heidelberg. A produção de biofilme está parcialmente associada com o sorovar da cepa. Também foi observado que existe variação quanto à produção destas estruturas dentro de um mesmo sorovar, indicando que possivelmente a produção de biofilme é cepa-dependente.(AU)
Descritores: Salmonella
Biofilmes
Sorogrupo
-Aves Domésticas/virologia
Temperatura Baixa
Temperatura Alta
Responsável: BR68.1 - Biblioteca Virginie Buff D'Ápice


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Id: biblio-893657
Autor: Figueiredo, Viviane Maria Gonçalves de; Pereira, Sarina Maciel Braga; Bressiani, Eduardo; Valera, Márcia Carneiro; Bottino, Marco Antônio; Zhang, Yu; Melo, Renata Marques de.
Título: Effects of porcelain thickness on the flexural strength and crack propagation in a bilayered zirconia system
Fonte: J. appl. oral sci;25(5):566-574, Sept.-Oct. 2017. tab, graf.
Idioma: en.
Projeto: US National Institute of Dental and Craniofacial Research.
Resumo: Abstract Objective: This study evaluated the influence of porcelain (VM9, VITA Zahnfabrik, Germany) thickness on the flexural strength and crack propagation in bilayered zirconia systems (YZ, VITA Zahnfabrik, Germany). Material and Methods: Thirty zirconia bars (20.0x4.0x1.0 mm) and six zirconia blocks (12.0x7.5x1.2 mm) were prepared and veneered with porcelain with different thickness: 1 mm, 2 mm, or 3 mm. The bars of each experimental group (n=10) were subjected to four-point flexural strength testing. In each ceramic block, a Vickers indentation was created under a load of 10 kgf for 10 seconds, for the propagation of cracks. Results: The results of flexural strength were evaluated by One-way ANOVA and Tukey's test, with a significance level of 5%. The factor "thickness of the porcelain" was statistically significant (p=0.001) and the l-mm group presented the highest values of flexural strength. The cracks were predominant among the bending specimens with 1 and 2 mm of porcelain, and catastrophic failures were found in 50% of 3-mm-thick porcelain. After the indentation of blocks, the most severe defects were observed in blocks with 3-mm-thick porcelain. Conclusion: The smallest (1 mm) thickness of porcelain on the zirconia infrastructure presented higher values of flexural strength. Better resistance to defect propagation was observed near the porcelain/ zirconia interface for all groups. Higher flexural strength was found for a thinner porcelain layer in a bilayered zirconia system. The damage caused by a Vickers indentation near and far the interface with the zirconia shows that the stress profiles are different.
Descritores: Zircônio/química
Cerâmica/química
Porcelana Dentária/química
-Valores de Referência
Propriedades de Superfície
Resistência à Tração
Fatores de Tempo
Teste de Materiais
Reprodutibilidade dos Testes
Análise de Variância
Maleabilidade
Microscopia Confocal
Falha de Restauração Dentária
Análise do Estresse Dentário
Testes de Dureza
Temperatura Alta
Tipo de Publ: Estudos de Avaliação
Responsável: BR1.1 - BIREME



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