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1.
Braz J Med Biol Res ; 56: e12546, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37703106

RESUMO

Intense stimulation of most living cells triggers the activation of immediate early genes, such as Fos and Jun families. These genes are important in cellular and biochemical processes, such as mitosis and cell death. The present study focused on determining the temporal expression pattern of Fos and Jun families in fibroblasts and neural stem cells of cerebellum, hippocampus, and subventricular zone (SVZ) of rats of different ages at 0, 0.5, 1, 3, and 6 h after stimulation with fibroblast growth factor (FGF)-2. In neonates, a similar expression pattern was observed in all cells analyzed, with lower expression in basal condition, peak expression at 0.5 h after stimulation, returning to baseline values between 1 and 3 h after stimulation. On the other hand, cells from adult animals only showed Fra1 and JunD expression after stimulation. In fibroblasts and hippocampus, Fra1 reached peak expression at 0.5 h after stimulation, while in the SVZ, peak level was observed at 6 h after stimulation. JunD in fibroblasts presented two peak expressions, at 0.5 and 6 h after stimulation. Between these periods, the expression observed was at a basal level. Nevertheless, JunD expression in SVZ and hippocampus was low and without significant changes after stimulation. Differences in mRNA expression in neonate and adult animals characterize the significant differences in neurogenesis and cell response to stimulation at different stages of development. Characterizing these differences might be important for the development of cell cultures, replacement therapy, and the understanding of the physiological response profile of different cell types.


Assuntos
Fator 2 de Crescimento de Fibroblastos , Células-Tronco Neurais , Animais , Ratos , Mitógenos , Proliferação de Células , Fibroblastos
2.
Braz. j. med. biol. res ; 56: e12546, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1505884

RESUMO

Intense stimulation of most living cells triggers the activation of immediate early genes, such as Fos and Jun families. These genes are important in cellular and biochemical processes, such as mitosis and cell death. The present study focused on determining the temporal expression pattern of Fos and Jun families in fibroblasts and neural stem cells of cerebellum, hippocampus, and subventricular zone (SVZ) of rats of different ages at 0, 0.5, 1, 3, and 6 h after stimulation with fibroblast growth factor (FGF)-2. In neonates, a similar expression pattern was observed in all cells analyzed, with lower expression in basal condition, peak expression at 0.5 h after stimulation, returning to baseline values between 1 and 3 h after stimulation. On the other hand, cells from adult animals only showed Fra1 and JunD expression after stimulation. In fibroblasts and hippocampus, Fra1 reached peak expression at 0.5 h after stimulation, while in the SVZ, peak level was observed at 6 h after stimulation. JunD in fibroblasts presented two peak expressions, at 0.5 and 6 h after stimulation. Between these periods, the expression observed was at a basal level. Nevertheless, JunD expression in SVZ and hippocampus was low and without significant changes after stimulation. Differences in mRNA expression in neonate and adult animals characterize the significant differences in neurogenesis and cell response to stimulation at different stages of development. Characterizing these differences might be important for the development of cell cultures, replacement therapy, and the understanding of the physiological response profile of different cell types.

3.
J Mech Behav Biomed Mater ; 94: 110-125, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30884280

RESUMO

Zirconia implants are becoming a preference choice for different applications such as knee, dental, among others. In order to improve osseointegration, implant's surfaces are usually coated with bioactive materials like hydroxyapatite (HAp) and beta-tricalcium phosphate (ß-TCP) that are very similar to the calcium phosphates found in bones. However, due to the implantation process, these coatings can be detached from the zirconia surface, leading to implant premature failure. In this work, a new component materials design aiming to avoid this coating detachment problem is proposed. It is based on the use of a bioactive zirconia-calcium phosphate composite outer layer onto the zirconia bulk, where the zirconia bulk provides mechanical strength and the outer layer provides biological performance. In order to assess the potential of this new materials design, two types of bioactive zirconia outer composite layers (zirconia reinforced by 10 vol% of HAp and by 10 vol% of ß-TCP) were produced by press and sinter process and the gradated samples were fully characterized concerning materials, mechanical resistance, fatigue resistance, and biological performance, as measured by different approaches. Results showed that the novel component materials design and the manufacturing process proposed for producing the bioactive zirconia samples with outer composite layers on zirconia bulk substrates are a promising solution for implants, with improved biological performance without substantially compromising their overall mechanical and fatigue properties.


Assuntos
Próteses e Implantes , Zircônio/química , Fosfatos de Cálcio/química , Durapatita/química , Módulo de Elasticidade , Dureza , Propriedades de Superfície , Temperatura , Molhabilidade
4.
Food Chem ; 109(4): 840-7, 2008 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-26049999

RESUMO

Consumers are very concerned in "Protected Designation of Origin" (PDO) products, namely meat, since they associate these products to quality and healthy foods. Thus, it is necessary to implement analytical methodologies that could assure consumers about the products they purchase. Since this kind of meat is usually sold with no information concerning cattle sex, age and slaughter season, these characteristics were intentionally not taken into account. In this study, two Portugueses PDO bovine breeds (Mirandesa and Barrosã) and two production sub-systems (traditional and organic farming) were studied during a two-year period. Statistical analysis showed that production system and breed had a significant effect on the overall raw meat fatty acids (FA) content. Besides, the FA profiles could be used as an effective tool to differentiate the four groups studied allowing a 100% correct classification. The meat FA content was also correlated with the relative importance of the animal feeding stuff area.

5.
Microbiol Res ; 158(2): 117-24, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12906384

RESUMO

AIMS: The main aims of this work were the study of cork slabs moulds colonization and the evaluation of the moulds diversity during cork processing steps, in different cork stoppers factories. Simultaneously, it was envisaged to perform an evaluation of the air quality. METHODS AND RESULTS: Moulds were isolated and identified from cork slabs and cork samples in four cork stoppers factories. The identification was based on morphological characters and microscopic observation of the reproductive structures. Airborne spore dispersion was assessed using a two stage Andersen sampler. It was observed that Chrysonilia sitophila was always present on cork slabs during the maturing period, but mould diversity appeared to be associated to the different factory configurations and processing steps. CONCLUSIONS: Spatial separation of the different steps of the process, including physical separation of the maturation step, is essential to guarantee high air quality and appropriate cork slabs colonization, i.e. C. sitophila dominance. The sorting and cutting of the edges of cork slabs after boiling and before the maturing step is also recommended. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is very important for the cork stopper industry as it gives clear indications on how to keep high quality manufacturing standards and how to avoid occupational health problems.


Assuntos
Microbiologia do Ar , Fungos/crescimento & desenvolvimento , Indústrias , Casca de Planta/microbiologia , Quercus/microbiologia , Fungos/classificação , Fungos/isolamento & purificação , Esporos Fúngicos
7.
J Pediatr (Rio J) ; 75(4): 281-6, 1999.
Artigo em Português | MEDLINE | ID: mdl-14685531

RESUMO

OBJECTIVE: To draw pediatrician's and healthcare worker's attention to the Munchausen syndrome by proxy, a serious kind of child abuse. PATIENTS AND METHODS: We report the clinical history and the evolution of two patients, based on a review of these patient's files in the Children's Rights Committee of the Hospital da Criança Santo Antônio, for further discussion. The first case reports a 5- year old child that presented difficult-controlling seizures; this case had an excellent prognosis after being examined by several specialists and later on by the Children's Right Committee. The second case reported is a 5-month old infant who presented apnea crisis accompanied by cyanosis and seizures. COMMENT: Munchausen syndrome by proxy is a relatively rare clinical entity, that can be difficult to be diagnosed, leading to unnecessary and potentially harmful diagnostic procedures to the child.

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