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1.
Sci Total Environ ; 849: 157828, 2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-35934022

RESUMO

External Thermal Insulation Composite Systems (ETICS) are multilayer solutions which provide an enhanced thermal performance to the building envelope. However, significant anomalies can be detected on ETICS facades, in some cases shortly after the application of these systems. This study intends to evaluate and compare the durability of six commercially available ETICS after two years of outdoor exposure at both urban and maritime conditions in Portugal. The systems were characterized by means of non-destructive testing (i.e., visual and microscopic assessment, water transport properties, thermal conductivity, surface roughness), thus allowing to evaluate the performance loss throughout natural aging. The bio-susceptibility and aesthetic properties (color and gloss) were also investigated. Results showed that the performance and durability of the complete system is significantly affected by the rendering system formulation. The lime-based specimens obtained the highest rate of mold development after one year of aging in a maritime environment, becoming considerably darker and with lower surface gloss. Fungal analysis of this darkish stained area indicated the presence of mold species of the genera Alternaria, Didymella, Cladosporium and Epicoccum, and yeasts of the genera Vishniacozyma and Cystobasidium. An increase of both capillary water absorption and water vapor permeability was also registered for the aged lime-based specimens. Acrylic-based systems obtained lower capillary water absorption after aging and greater dirt deposition on their surfaces, especially in urban conditions. These systems had also higher color variation and surface gloss decrease and slightly higher mold growth, when compared with those aged in a maritime environment. Finally, no mold growth was detected on the silicate-based specimens after two years of aging. However, these specimens obtained higher capillary water absorption and lower vapor permeability after aging, possibly leading to moisture accumulation within the system. Results contribute towards the development of ETICS with enhanced performance and durability.


Assuntos
Resinas Compostas , Vapor , Compostos de Cálcio , Teste de Materiais , Óxidos , Propriedades de Superfície
2.
Stem Cell Rev Rep ; 8(4): 1211-22, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22773405

RESUMO

Mesenchymal stem cells have a great potential for application in cell based therapies, such as tissue engineering. Adipose derived stem cells have shown the capacity to differentiate into several lineages, and have been isolated in many animal species. Dog is a very relevant animal model to study several human diseases and simultaneously an important subject in veterinary medicine. Thus, in this study we assessed the potential of canine adipose tissue derived stem cells (cASCs) to differentiate into the osteogenic and chondrogenic lineages by performing specific histological stainings, and studied the cell passaging effect on the cASCs stemness and osteogenic potential. We also evaluated the effect of the anatomical origin of the adipose tissue, namely from abdominal subcutaneous layer and from greater omentum. The stemness and osteogenic differentiation was followed by real time RT-PCR analysis of typical markers of mesenchymal stem cells (MSCs) and osteoblasts. The results obtained revealed that cASCs exhibit a progressively decreased expression of the MSCs markers along passages and also a decreased osteogenic differentiation potential. In the author's knowledge, this work presents the first data about the MSCs markers profile and osteogenic potential of cASCs along cellular expansion. Moreover, the obtained data showed that the anatomical origin of the adipose tissue has an evident effect in the differentiation potential of the ASCs. Due to the observed resemblances with the human ASCs, we conclude that canine ASCs can be used as a model cells in tissue engineering research envisioning human applications.


Assuntos
Tecido Adiposo/citologia , Osteogênese , Células-Tronco/citologia , Tecido Adiposo/metabolismo , Animais , Antígenos de Diferenciação/biossíntese , Técnicas de Cultura de Células/métodos , Células Cultivadas , Cães , Feminino , Humanos , Masculino , Especificidade de Órgãos , Células-Tronco/metabolismo
3.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);63(1): 40-45, Feb. 2011. tab
Artigo em Inglês | LILACS | ID: lil-582322

RESUMO

Values of serum tartrate-resistant acid phosphatase ( TRAP) activity were obtained in adult dogs and its biological variability was assessed. Nine healthy skeletally mature Portuguese Podengo dogs were used for the determination of TRAP, total and bone alkaline phosphatase serum activities, and also to study their relationship with serum minerals, namely calcium (Ca), phosphorous (P), and magnesium (Mg). The serum TRAP activity was 2.19±0.56IU/mL, with intra-individual variation of 18.3 percent and inter-individual variation of 25.6 percent. Significant correlations were observed between serum TRAP activity and Ca (r=-0.3431; P<0.05), Ca and Mg (r=-0.787; P<0.01), and TRAP and Mg (r=0.397; P<0.05). The results indicate that serum TRAP activity in dog could be of great value in research and in clinical practice, providing complementary non-invasive information on bone metabolism.


Determinaram-se os valores da atividade da fosfatase ácida resistente ao tartarato (FART) e avaliou-se a sua variabilidade biológica. Neste estudo, foram utilizados nove cães adultos e saudáveis de raça Podengo Português para as determinações das atividades da FART, da fosfatase alcalina total, da isoenzima óssea da fosfatase alcalina e da concentração dos minerais séricos - cálcio, fósforo e magnésio. A atividade sérica obtida da FART foi de 2,19±0,56 UI/mL, com uma variação intra-individual de 18,3 por cento e interindividual de 25,6 por cento. Foram observadas correlações significativas ao longo do tempo entre FART e cálcio (r=-0,3431; P<0,05), entre FART e magnésio (r=0,3974; P<0,05) e entre cálcio e magnésio (r=-0,787; P<0,01). Os resultados indicam que este marcador de reabsorção óssea pode ser de grande valor na prática clínica e na investigação e, ainda, ser utilizado como um método auxiliar não invasivo para avaliação do metabolismo ósseo.


Assuntos
Animais , Cães/classificação , Fosfatase Ácida/análise , Cálculos Dentários , Isoenzimas/síntese química , Minerais/análise
4.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);62(2): 265-272, abr. 2010. tab
Artigo em Inglês | LILACS | ID: lil-551826

RESUMO

Hematological and biochemical parameters, including plasma electrolytes and thyroid hormones, were determined in 73 clinically healthy Churra-da-Terra-Quente ewes, a typical breed from the northeast of Portugal. The hemogram values were: erythrocytes 9.8±1.5×10(12)/L; haemoglobin 118.1±19.1g/L; haematocrit 40.8±5.9 percent; leukocytes 5.7±1.8×10(9)/L; and platelets 544.3±177.2×10(9)/L. The thrombin time was 17.3±1.7 seconds. The values of biochemical parameters were: total protein 76.4±6.1g/L; glucose 2.87±0.60mmol/L; total cholesterol 1.65±0.33mmol/L; aspartate aminotransferase 155.9±49.2U/L; alanine aminotransferase 23.2±9.6U/L; γ-glutamyl transferase 48.0±18.7U/L; total alkaline phosphatase 121.6±76.1U/L; glutamate dehydrogenase 6.4±3.7U/L; urea 7.32±2.22mmol/L; creatinine 123.0±54.1μmol/L; total calcium 2.53±0.25mmol/L; phosphorus 2.10±0.46mmol/L; magnesium 1.01±0.09mmol/L; sodium 152.04±3.65mmol/L; potassium 4.7±0.4mmol/L; ionized calcium 1.32±0.07mmol/L; total thyroxine 111.75±42.29nmol/L; total triiodothyronine 1.01±0.28nmol/L; free T4 11.93±1.78pmol/L; free T3 4.22±1.33pmol/L; and thyroid-stimulating hormone 0.18±0.19μIU/mL. Although differences among the Churra-da-Terra-Quente breed and other breeds may occur, the hematological and biochemical parameters, plasma electrolytes, and thyroid hormones, for this indigenous breed, were generally situated within the reference intervals previously reported for sheep.


Os valores hematológicos e bioquímicos, incluindo os eletrólitos plasmáticos e os hormônios da tireoide, foram determinados em 73 ovelhas, clinicamente saudáveis, da raça Churra da Terra Quente, raça ovina característica do nordeste de Portugal. Os valores obtidos para o hemograma foram: eritrócitos 9,8±1,5×10(12) /L; hemoglobina 118,1±19,1g/L; hematócrito 40,8±5,9 por cento; leucócitos 5,7±1,8×10(9) /L e plaquetas 544,3±177,2×10(9)/L. O tempo de trombina foi de 17,3±1,7 segundos. Os valores dos parâmetros bioquímicos avaliados foram: proteínas totais 76,4±6,1g/L; glicose 2,87±0,60mmol/L; colesterol total 1,65±0,33mmol/L; aspartato amino transferase 155,9±49,2U/L; alanina amino transferase 23,2±9,6U/L; gama-glutamil transferase 48,0±18,7U/L; fosfatase alcalina total 121,6±76,1U/L; glutamato desidrogenase 6,4±3,7U/L; ureia 7,32±2,22mmol/L; creatinina 123,0±54,1μmol/L; cálcio total 2,53±0,25mmol/L; fósforo 2,10±0,46mmol/L e magnésio 1,01±0,09mmol/L; sódio 152,04±3,65mmol/L; potássio 4,7±0,4mmol/L e cálcio ionizado 1,32±0,07mmol/L; tiroxina total 111,75±42,29nmol/L; tri-iodotironina total 1,01±0,28nmol/L; T4 livre 11,93±1,78pmol/L; T3 livre 4,22±1,33pmol/L e hormônio estimulante da tireoide 0,18±0,19μIU/mL. Apesar de terem sido observadas algumas diferenças entre a raça Churra da Terra Quente e outras raças, os valores hematológicos e bioquímicos, eletrólitos plasmáticos e hormônios da tireóide, desta raça autóctone apresentam-se no geral situados dentro dos intervalos de referência publicados para a espécie ovina.


Assuntos
Animais , Enzimas/análise , Enzimas/sangue , Tiroxina/análise , Ovinos/fisiologia , Ovinos/genética
5.
Arch Microbiol ; 175(4): 301-7, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11382226

RESUMO

Acquisition of resistance to lethal concentrations of octanoic acid was induced in cells of Saccharomyces cerevisiae grown in the presence of sublethal concentrations of this lipophilic acid or following rapid exposure (1 h) of unadapted yeast cells to mild stress imposed by the same acid. Experimental evidence indicated that the referred adaptation involved de novo protein synthesis, presumably due to the rapid induction of a plasma membrane transporter which mediates the active efflux of octanoate out of the cell. Rapid exposure of cells to mild ethanol stress also led to increased resistance to lethal concentrations of octanoic acid. This cross-resistance to octanoic-acid-induced death was below the level of resistance induced by mild octanoic acid stress and did not involve induction of the active expulsion of octanoate out of the cell. However, the rapid exposure of yeast cells to octanoic acid or ethanol led to the activation of plasma membrane H+-ATPase. The physiological role of the two stress responses examined during the present study, namely, the active efflux of octanoate specifically induced by octanoic acid and the stimulation of plasma membrane H+-ATPase activity, is discussed.


Assuntos
Caprilatos/farmacologia , Etanol/farmacologia , Saccharomyces cerevisiae/efeitos dos fármacos , Adaptação Fisiológica , Ativação Enzimática , ATPases Translocadoras de Prótons/metabolismo
6.
Yeast ; 15(15): 1595-608, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10572257

RESUMO

In this work we report the disruption of a Saccharomyces cerevisiae ORF YBR008c (FLR1 gene) within the context of EUROFAN (EUROpean Functional Analysis Network) six-pack programme, using a PCR-mediated gene replacement protocol as well as the results of the basic phenotypic analysis of a deletant strain and the construction of a disruption cassette for inactivation of this gene in any yeast strain. We also show results extending the knowledge of the range of compounds to which FLR1 gene confers resistance to the antimitotic systemic benzimidazole fungicide benomyl and the antitumor agent methotrexate, reinforcing the concept that the FLR1 gene is a multidrug resistance (MDR) determinant. Our conclusions were based on the higher susceptibility to these compounds of flr1Delta compared with wild-type and on the increased resistance of both flr1Delta and wild-type strains upon increased expression of FLR1 gene from a centromeric plasmid clone. The present study also provides, for the first time, evidence that the adaptation of yeast cells to growth in the presence of benomyl involves the dramatic activation of FLR1 gene expression during benomyl-induced latency (up to 400-fold). Results obtained using a FLR1-lacZ fusion in a plasmid indicate that the activation of FLR1 expression in benomyl-stressed cells is under the control of the transcriptional regulator Pdr3p. Indeed, PDR3 deletion severely reduces benomyl-induced activation of FLR1 gene expression (by 85%), while the homologous Pdr1p transcription factor is apparently not involved in this activation.


Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Proteínas de Transporte/genética , Proteínas de Ligação a DNA/genética , Fungicidas Industriais/farmacologia , Regulação Fúngica da Expressão Gênica , Proteínas de Membrana Transportadoras , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Fatores de Transcrição/genética , 4-Nitroquinolina-1-Óxido/farmacologia , Antifúngicos/farmacologia , Benomilo/farmacologia , Carcinógenos/farmacologia , Cicloeximida/farmacologia , Primers do DNA/química , DNA Fúngico/química , Resistência Microbiana a Medicamentos/genética , Eletroforese em Gel de Ágar , Fluconazol/farmacologia , Metotrexato/farmacologia , Mutagênese Insercional , Transportadores de Ânions Orgânicos , Plasmídeos/química , Reação em Cadeia da Polimerase , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/efeitos dos fármacos
7.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;32(4): 407-11, Apr. 1999. tab, graf
Artigo em Inglês | LILACS | ID: lil-231730

RESUMO

We analyzed the flow-volume curves of 50 patients with complaints of snoring and daytime sleepiness in treatment at the Pneumology Unit of the University Hospital of Brasília. The total group was divided into snorers without obstructive sleep apnea (OSA) (N = 19) and snorers with OSA (N = 31); the patients with OSA were subdivided into two groups according to the apnea/hypopnea index (AHI): AHI<20/h (N = 14) and AHI>20/h (N = 17). The control group (N = 10) consisted of nonsmoking subjects without complaints of snoring, daytime sleepiness or pulmonary diseases. The population studied (control and patients) consisted of males of similar age, height and body mass index (BMI); spirometric data were also similar in the four groups. There was no significative difference in the ratio of forced expiratory and inspiratory flows (FEF50 per cent/FIF50 per cent) in any group: control, 0.89; snorers, 1.11; snorers with OSA (AHI<20/h), 1.42, and snorers with OSA (AHI>20/h), 1.64. The FIF at 50 per cent of vital capacity (FIF50 per cent) of snoring patients with or without OSA was lower than the FIF50 per cent of the control group (P<0.05): snorers 4.30 l/s; snorers with OSA (AHI>20/h) 3.69 l/s; snorers with OSA (AHI>20/h) 3.17 l/s and control group 5.48 l/s. The FIF50 per cent of patients with severe OSA (AHI>20/h) was lower than the FIF50 per cent of snorers without OSA (P<0.05): 3.17 l/s and 4.30 l/s, respectively. We conclude that 1) the FEF50 per cent/FIF50 per cent ratio is not useful for predicting OSA, and 2) FIF50 per cent is decreased in snoring patients with and without OSA, suggesting that these patients have increased upper airway resistance (UAR).


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Ventilação Pulmonar , Síndromes da Apneia do Sono/fisiopatologia , Ronco/fisiopatologia , Capacidade Inspiratória , Testes de Função Respiratória , Capacidade Vital
8.
Appl Environ Microbiol ; 64(2): 779-83, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9464423

RESUMO

Saccharomyces cerevisiae plasma membrane H(+)-ATPase activity was stimulated during octanoic acid-induced latency, reaching maximal values at the early stages of exponential growth. The time-dependent pattern of ATPase activation correlated with the decrease of cytosolic pH (pHi). The cell population used as inoculum exhibited a significant heterogeneity of pHi, and the fall of pHi correlated with the loss of cell viability as determined by plate counts. When exponential growth started, only a fraction of the initial population was still viable, consistent with the role of the physiology and number of viable cells in the inoculum in the duration of latency under acid stress.


Assuntos
Caprilatos/farmacologia , ATPases Translocadoras de Prótons/metabolismo , Saccharomyces cerevisiae/enzimologia , Membrana Celular/enzimologia , Meios de Cultura , Ativação Enzimática , Concentração de Íons de Hidrogênio , Saccharomyces cerevisiae/fisiologia
9.
Appl Environ Microbiol ; 61(5): 1904-9, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7646027

RESUMO

During exponential growth at temperatures of 30 to 39 degrees C, the specific activity of H(+)-ATPase in the plasma membrane of Saccharomyces cerevisiae (assayed at the standard temperature 30 degrees C) increased with increases in growth temperature. In addition, the optimal temperature for in vitro activity of this ATPase was 42 degrees C. Therefore, the maximum values of ATPase activity were expected to occur in cells that grew within the supraoptimal range of temperatures. Activation induced by supraoptimal temperatures was not the result of increased synthesis of this membrane enzyme. When the growth temperature increased from 30 to 40 degrees C, expression of the essential PMA1 gene, monitored either by the level of PMA1 mRNA or the beta-galactosidase activity of the lacZ-PMA1 fusion, was reduced. Consistently, quantitative immunoassays showed that the ATPase content in the plasma membrane decreased. Like ATPase activity, the efficiency of the PMA2 promoter increased with increases in growth temperature in cells that had been grown at 30 to 39 degrees C, but its level of expression was several hundred-fold lower than that of PMA1. These results suggest that the major PMA1 ATPase is activated at supraoptimal temperatures.


Assuntos
Proteínas Fúngicas/metabolismo , Regulação Enzimológica da Expressão Gênica , Regulação Fúngica da Expressão Gênica , Temperatura Alta , Isoenzimas/metabolismo , Proteínas de Membrana/metabolismo , ATPases Translocadoras de Prótons/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/enzimologia , Ativação Enzimática , Proteínas Fúngicas/genética , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Isoenzimas/genética , ATPases Translocadoras de Prótons/genética , Proteínas Recombinantes de Fusão/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento
10.
Biochim Biophys Acta ; 1217(1): 74-80, 1994 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-8286419

RESUMO

A peak of plasma membrane H(+)-ATPase activity during exponential growth is correlated with the expression of the PMA1 gene as monitored by measurements of the beta-galactosidase activity from a PMA1-lacZ fusion. This peak of activity is also correlated to the content of the H(+)-ATPase protein in yeast plasma membrane as shown by quantitative immunodetection. The PMA2-lacZ fusion assay indicates that the expression of the PMA2 gene is activated somewhat later during exponential phase but under all circumstances its activity remains at least 500-fold lower than that of the PMA1-lacZ fusion. A slight but significant stimulation of ATPase activity by low concentrations of octanoic acid coincides with a decrease in the PMA1 gene expression. It is concluded that octanoic acid stimulates de PMA1 ATPase activity by posttranslational mechanisms.


Assuntos
Caprilatos/farmacologia , Regulação Enzimológica da Expressão Gênica , Genes Fúngicos , ATPases Translocadoras de Prótons/genética , Saccharomyces cerevisiae/enzimologia , Membrana Celular/enzimologia , Clonagem Molecular , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/crescimento & desenvolvimento
11.
J Gen Microbiol ; 137(3): 645-51, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1827836

RESUMO

Plasma membrane ATPase activity of Saccharomyces cerevisiae IGC 3507III grown in the presence of the lipophilic acid octanoic acid [4-50 mg l-1 (0.03-0.35 mM), pH 4.0] was 1.5-fold higher than that in cells grown in its absence. The Km for ATP, the pH profile and the sensitivity to orthovanadate of the basal and the activated forms of the membrane ATPase were identical. This activation was closely associated with a decrease in the biomass yield and an increase in the ethanol yield, and was rapidly reversed in vivo after removal of the acid. However, the activated level was preserved when membranes were extracted and subjected to manipulations which eliminated or decreased octanoic acid incorporation in the plasma membrane. The activity of the basal plasma membrane ATPase in the total membrane fraction was slightly increased by incubation at pH 6.5 with octanoic acid at 100 mg l-1 or less (2.4 mg acid form plus 97.6 mg octanoate ion l-1). However, destruction of the permeability barrier between the enzyme and its substrate could not explain the in vivo activation. A role for plasma membrane ATPase activation in the regulation of the intracellular pH (pHi) of cells grown with octanoic acid was not proven.


Assuntos
Adenosina Trifosfatases/metabolismo , Caprilatos/metabolismo , Membrana Celular/enzimologia , Saccharomyces cerevisiae/enzimologia , Caprilatos/toxicidade , Ativação Enzimática , Etanol/metabolismo , Concentração de Íons de Hidrogênio , Cinética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Vanadatos/metabolismo
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