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1.
Actual. osteol ; 18(2): 60-74, oct. 2022. graf, ilus, tab
Artigo em Espanhol | LILACS, UNISALUD, BINACIS | ID: biblio-1437640

RESUMO

Introducción: Los GOS son prebióticos naturales presentes en la leche materna que pue-den obtenerse enzimáticamente a partir de la lactosa de leche de vaca durante la fabricación de yogur. El producto lácteo resultante será reducido en lactosa y contendrá prebióticos y bacterias potencialmente probióticas. Sin embargo, mantendrá la baja relación Ca/Pi que aporta la leche de vaca, lo que podría alterar el remodelamiento óseo y la mineralización. Objetivo: comparar si un yogur reducido en lactosa que contiene GOS (YE) ofrece ventajas adicionales respecto de un yogur regular sin GOS (YR) sobre las absorciones (Abs) de Ca y Pi, retención y calidad ósea durante el crecimiento normal. Al destete, ratas machos fueron divididas en 3 grupos alimentados con AIN ́93-G (C), YE o YR durante 28 días. Resultados: YE mostró el mayor aumento de lactobacilos fecales; producción de ácidos grasos de cadena corta especialmente p, profundidad de las criptas colónicas y menor pH cecal. El %AbsCa y %AbsPi aumentó en el siguiente órden: YE> YR> C (p < 0,05). El contenido de Ca y Pi en fémur, la densidad y contenido mineral óseos y los parámetros biomecánicos fueron similares en YE y C, mientras que YR mostró valores significativa-mente menores (p < 0,05). Conclusiones: YE aumentó las Abs y biodisponibilidad de minerales, alcanzando la retención y calidad ósea de C. El aumento en las Abs observado en YR no logró obtener la retención y calidad ósea de C. Conclusión: YE habría contrarrestado el efecto negativo del mayor aporte de Pi de la leche de vaca y sería una buena estrategia para lograr el pico de masa ósea y calidad del hueso adecuados, especialmente en individuos intolerantes a la lactosa. (AU)


Breast milk contains an optimal calcium/phosphate (Ca/Pi) ratio and GOS. These natural prebiotics can be enzymatically produced via cow's milk lactose inyogurt manufacture. This milk product is low in lactose and contains prebiotics and potentially probiotic bacteria but maintains a low Ca/Pi ratio that could alter bone remodeling and mineralization. We evaluated if a lactose-reduced yogurt containing GOS (YE) offers additional advantages over regular yogurt without GOS (YR) on Ca and Pi absorption (Abs), bone retention and quality during normal growth. Weaning male rats were divided into 3 groups fed AIN'93-G (C), YE or YR for 28 days. Results: YE showed the highest increase in fecal lactobacilli; short-chain fatty acids production, especially propionate and butyrate; intestine crypt depth, and the lowest cecal pH. AbsCa% and AbsPi% increased in this order: YE> YR> C (p <0.05). Ca and Pi content in femur, bone density and mineral content, and biomechanical parameters were similar in YE and C, while YR showed the significantly lowest value (p < 0.05). Conclusions: YE increased mineral Abs reaching the retention and bone quality of C. Although YR increased Abs, bone retention and quality did not achieve C values. Seemingly, YE compensated for the negative effect of the higher Pi supply and would be a good strategy to achieve adequate peak bone mass and bone quality, especially in lactose intolerant individuals. (AU)


Assuntos
Animais , Ratos , Oligossacarídeos/metabolismo , Osteogênese/fisiologia , Cálcio da Dieta/farmacocinética , Fósforo na Dieta/farmacocinética , Absorção Intestinal/fisiologia , Lactose/metabolismo , Magnésio/farmacocinética , Tíbia/anatomia & histologia , Iogurte/análise , Cálcio da Dieta/metabolismo , Absorciometria de Fóton , Densidade Óssea , Interpretação Estatística de Dados , Fósforo na Dieta/metabolismo , beta-Galactosidase/síntese química , Ratos Wistar , Lactobacillus delbrueckii/isolamento & purificação , Fêmur/anatomia & histologia , Intestino Grosso/anatomia & histologia , Magnésio/metabolismo , Valor Nutritivo
3.
Electron J Biotechnol ; 49: 14-21, Jan. 2021. graf, tab
Artigo em Inglês | LILACS | ID: biblio-1291625

RESUMO

BACKGROUND: Milk whey, a byproduct of the dairy industry has a negative environmental impact, can be used as a raw material for added-value compounds such as galactooligosaccharides (GOS) synthesis by bgalactosidases. RESULTS: B-gal42 from Pantoea anthophila strain isolated from tejuino belonging to the glycosyl hydrolase family GH42, was overexpressed in Escherichia coli and used for GOS synthesis from lactose or milk whey. Crude cell-free enzyme extracts exhibited high stability; they were employed for GOS synthesis reactions. In reactions with 400 g/L lactose, the maximum GOS yield was 40% (w/w) measured by HPAEC-PAD, corresponding to 86% of conversion. This enzyme had a strong predilection to form GOS with b(1 ? 6) and b (1 ? 3) galactosyl linkages. Comparing GOS synthesis between milk whey and pure lactose, both of them at 300 g/L, these two substrates gave rise to a yield of 38% (60% of lactose conversion) with the same product profile determined by HPAEC-PAD. CONCLUSIONS: B-gal42 can be used on whey (a cheap lactose source) to produce added value products such as galactooligosaccharides.


Assuntos
Oligossacarídeos/biossíntese , beta-Galactosidase/metabolismo , Pantoea , Lactose/metabolismo , Proteínas Recombinantes , Indústria de Laticínios , Soro do Leite
4.
Braz. arch. biol. technol ; 64: e21180747, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1345490

RESUMO

Abstract Owing to the excellent catalytic potential, β-galactosidase (EC: 3.2.1.23) has been exploited as an important industrial enzyme for obtaining galactooligosaccharides (GOS) and lactose-free products in dairy industries. Moreover, novel technologies have been implemented in the recent past for preparing and modifying nanoparticles (NPs) for immobilizing therapeutically and industrially important enzymes. Nanoparticles based enzyme immobilization (NBEI) offered more stability and robustness to the enzymes due to their fixed conformation and hence extend their applications in broader areas. A quick overview of the results exhibited greater activity for the enzymes immobilized on NPs as compared to enzyme immobilized on 2-D matrices. Based on these findings, this review was aimed to emphasize the recent development achieved for immobilizing β-galactosidase on NPs with their specific utilization in obtaining dairy products. These studies includes β-galactosidases from various sources that were immobilized on various NPs for hydrolyzing lactose in batch and continuous reactors, and for the production of GOS in biotechnology industries. NBEI of β-galactosidase offered profound stability for transporting substrate and product for enzymatic reactions, apart from cost effective advantage due to reusable nature of immobilized enzyme.


Assuntos
beta-Galactosidase , Indústria de Laticínios , Enzimas , Nanopartículas
5.
Rev. chil. nutr ; 47(1): 14-21, feb. 2020. graf
Artigo em Espanhol | LILACS | ID: biblio-1092739

RESUMO

Se evaluó el efecto de la temperatura sobre la desnaturalización de proteínas y la reacción de Maillard en leche entera y descremada con lactosa hidrolizada. Las leches hidrolizadas se trataron térmicamente a 100, 110, 120 y 130 °C durante un período de 1 hora y se midió la concentración de glucosa, el grado de pardeamiento y la desnaturalización de proteínas. El grado de dorado en la leche entera varió de 14.4 (100 °C) a 42.6 (130 °C). Para la leche descremada fue de 20.2 (100 °C) a 38.0 (130 °C). La concentración de glucosa en leche entera (47% p/v) y en leche descremada (41% p/v) después del tratamiento térmico (130 °C) mostró una reducción significativa en relación con el control (25 °C). El efecto de la temperatura en la desnaturalización de proteínas en leche entera y descremada en relación con el control (25 °C) fue del 100%. La leche tratada térmicamente con lactosa hidrolizada promovió la desnaturalización de proteínas con un aumento del pardeamiento característico de la reacción de Maillard, lo que afectó la calidad nutricional.


The effect of temperature in protein denaturation and Maillard reaction in whole and skim milk with hydrolyzed lactose was evaluated. Hydrolyzed milk was thermally treated at 100, 110, 120 and 130 °C over a period of 1 hour and glucose concentration, browning degree and protein denaturation were measured. The browning degree in whole milk varied from 14.42 (100 °C) to 42.63 (130 °C) and 20.21 (100 °C) to 38.03 (130 °C) in skim milk. Glucose concentration in whole milk (47% - w/v) and skim milk (41% - w/v) after heat treatment (130 °C) showed a significant reduction in relation to the control (25 °C). The temperature effect in protein denaturation in whole and skim milk in relation to the control (25 °C) was 100%. Thermally treated milk with hydrolyzed lactose promoted protein denaturation with increasing browning characteristic of the Maillard reaction, thus affecting the nutritional quality.


Assuntos
Desnaturação Proteica , Temperatura , Reação de Maillard , Leite/química , Lactose/química , Tratamento Térmico , beta-Galactosidase , Cor , Glucose/análise , Hidrólise
6.
Electron. j. biotechnol ; 40: 78-83, July. 2019. tab, graf, ilus
Artigo em Inglês | LILACS | ID: biblio-1053493

RESUMO

Background: Mathematical modeling is useful in the analysis, prediction, and optimization of an enzymatic process. Unlike the conventional modeling methods, Monte Carlo method has special advantages in providing representations of the molecule's spatial distribution. However, thus far, Monte Carlo modeling of enzymatic system is namely based on unimolecular basis, not suitable for practical applications. In this research, Monte Carlo modeling is performed for enzymatic hydrolysis of lactose for the purpose of real-time applications. Results: The enzyme hydrolysis of lactose, which is conformed to Michaelis­Menten kinetics, is modeled using the Monte Carlo modeling method, and the simulation results prove that the model predicts the reaction kinetics very well. Conclusions: Monte Carlo modeling method can be used to model enzymatic reactions in a simple way for real-time applications.


Assuntos
Método de Monte Carlo , Enzimas/metabolismo , Hidrólise , Lactose/metabolismo , Fatores de Tempo , Cinética , beta-Galactosidase/metabolismo , Enzimas Imobilizadas , Galactose/metabolismo
7.
Electron. j. biotechnol ; 27: 37-43, May. 2017. tab, ilus, graf
Artigo em Inglês | LILACS | ID: biblio-1010283

RESUMO

Background: ß-Galactosidases catalyze both hydrolytic and transgalactosylation reactions and therefore have many applications in food, medical, and biotechnological fields. Aspergillus niger has been a main source of ß-galactosidase, but the properties of this enzyme are incompletely studied. Results: Three new ß-galactosidases belonging to glycosyl hydrolase family 35 from A. niger F0215 were cloned, expressed, and biochemically characterized. In addition to the known activity of LacA encoded by lacA, three putative ß-galactosidases, designated as LacB, LacC, and LacE encoded by the genes lacB, lacC, and lacE, respectively, were successfully cloned, sequenced, and expressed and secreted by Pichia pastoris. These three proteins and LacA have N-terminal signal sequences and are therefore predicted to be extracellular enzymes. They have the typical structure of fungal ß-galactosidases with defined hydrolytic and transgalactosylation activities on lactose. However, their activity properties differed. In particular, LacB and lacE displayed maximum hydrolytic activity at pH 4­5 and 50°C, while LacC exhibited maximum activity at pH 3.5 and 60°C. All ß-galactosidases performed transgalactosylation activity optimally in an acidic environment. Conclusions: Three new ß-galactosidases belonging to glycosyl hydrolase family 35 from A. niger F0215 were cloned and biochemically characterized. In addition to the known LacA, A. niger has at least three ß-galactosidase family members with remarkably different biochemical properties.


Assuntos
Aspergillus niger/enzimologia , beta-Galactosidase/química , Especificidade por Substrato , Cinética , Sequência de Aminoácidos , Clonagem Molecular , beta-Galactosidase/genética , beta-Galactosidase/metabolismo
8.
Acta sci., Biol. sci ; 38(2): 149-155, abr.-jun. 2016.
Artigo em Inglês | LILACS | ID: biblio-2531

RESUMO

The permeabilization was used to transform microorganisms in cell biocatalysts with high enzymatic activity. The Saccharomyces fragilis IZ 275 yeast cells were permeabilized with ethanol, as permeabilizing agent. To optimize the permeabilization conditions were used the design of Box-Behnken 15 trials (3 central points). The independent variables and their levels were ethanol (29, 32 and 35%), temperature (15, 20 and 25°C) and time (15, 20 and 25 min). The answer (Y) function has beta-galactosidase activity (U mg-1). The optimum conditions for obtaining a high enzymatic activity were observed in 35% ethanol concentration, temperature 15ºC and 20 min. treatment time. The maximum activity of the enzyme beta-galactosidase obtained was 10.59 U mg-1. The permeabilization of the S. fragilis IZ 275 cells was efficient.


A permeabilização foi usada para transformar células de microrganismos em biocatalisadores com alta atividade enzimática. As células de levedura de Saccharomyces fragilis IZ 275 foram permeabilizadas com etanol, como agente permeabilizante. Para otimizar as condições de permeabilização foi utilizado o delineamento de Box-Behnken com 15 ensaios (3 repetições no ponto central) . As variáveis independentes e seus níveis foram etanol (29, 32 e 35%), temperatura (15, 20 e 25ºC) e tempo (15, 20 e 25 min.). A função resposta (Y) foi atividade de beta-galactosidase (U mg-1). As condições ótimas para a obtenção de uma alta atividade enzimática foram observadas em 35% de concentração de etanol, temperatura de 15°C e tempo de tratamento de 20 minutos. A máxima atividade da enzima beta-galactosidase obtida foi de 10.59 U mg-1. A permeabilização das células de S. fragilis IZ 275 foi eficiente.


Assuntos
Saccharomyces , beta-Galactosidase , Permeabilidade , Saccharomyces , Leveduras , Biotecnologia , Biocatálise , Hidrólise , Lactose
9.
Biol. Res ; 49: 1-16, 2016. ilus, graf
Artigo em Inglês | LILACS | ID: biblio-950861

RESUMO

BACKGROUND: Cellular senescence is induced either internally, for example by replication exhaustion and cell division, or externally, for example by irradiation. In both cases, cellular damages accumulate which, if not successfully repaired, can result in senescence induction. Recently, we determined the transcriptional changes combined with the transition into replicative senescence in primary human fibroblast strains. Here, by γ-irradiation we induced premature cellular senescence in the fibroblast cell strains (HFF and MRC-5) and determined the corresponding transcriptional changes by high-throughput RNA sequencing. RESULTS: Comparing the transcriptomes, we found a high degree of similarity in differential gene expression in replicative as well as in irradiation induced senescence for both cell strains suggesting, in each cell strain, a common cellular response to error accumulation. On the functional pathway level, "Cell cycle" was the only pathway commonly down-regulated in replicative and irradiation-induced senescence in both fibroblast strains, confirming the tight link between DNA repair and cell cycle regulation. However, "DNA repair" and "replication" pathways were down-regulated more strongly in fibroblasts undergoing replicative exhaustion. We also retrieved genes and pathways in each of the cell strains specific for irradiation induced senescence. CONCLUSION: We found the pathways associated with "DNA repair" and "replication" less stringently regulated in irradiation induced compared to replicative senescence. The strong regulation of these pathways in replicative senescence highlights the importance of replication errors for its induction.


Assuntos
Humanos , Masculino , Senescência Celular/fisiologia , Fibroblastos/efeitos da radiação , Fatores de Tempo , Dano ao DNA , Immunoblotting , Regulação para Baixo/efeitos da radiação , Regulação para Cima/efeitos da radiação , Células Cultivadas , Análise de Variância , Senescência Celular/efeitos da radiação , Senescência Celular/genética , beta-Galactosidase/metabolismo , Análise de Sequência de RNA , Perfilação da Expressão Gênica , Feto Abortado , Reparo do DNA/efeitos da radiação , Replicação do DNA/efeitos da radiação , Fibroblastos/fisiologia , Raios gama , Pulmão
10.
Rev. ciênc. farm. básica apl ; 36(1)mar. 2015. tab
Artigo em Inglês | LILACS | ID: lil-761234

RESUMO

An alternative to relieve the symptoms of lactose intolerance is the intake of the enzyme ?-galactosidase in pharmaceutical dosage forms. The ability of ?-galactosidase produced by Kluyveromyces lactis and Aspergillus oryzae to hydrolyze lactose in simulated conditions of the human gastrointestinal tract was investigated. The experiment was carried out in the optimum temperature for each enzyme activity, 40 and 55°C, respectively, and at the normal human body temperature (37°C) at concentrations of 1.5, 3.0, and 5.0 g/L (enzyme from A. oryzae) or mL/L (enzyme from K. lactis). Both enzymes were completely inactivated under simulated gastric conditions (pH 2). When the enzymes were subjected to simulated small intestine conditions (pH 7.4), lactose hydrolysis has occurred, but at 37°C the percentage was lower than that under the optimal temperatures. At concentrations of 1.5, 3.0, and 5.0 mL/L the enzyme from K. lactis hydrolyzed 76.63%, 88.91% and 94.80% of lactose at 40°C, and 55.99%, 80.91% and 81.53% at 37°C, respectively. In contrast, the enzyme from A. oryzae hydrolyzed 7.11%, 16.18% and 21.29% at 55°C, and 8.4%, 11.85% and 16.43% at 37°C. It was observed that under simulated intestinal conditions, the enzyme from K. lactis was more effective on lactose hydrolysis as compared to the enzyme from A. oryzae. Considering the findings of this study, it is extremely necessary to use an enteric coating on ?-galactosidase capsules so that this enzyme is released only in the small intestine, which is its site of action, thus not suffering the action of the stomach pH.(AU)


Uma das alternativas para amenizar os sintomas da intolerância à lactose é a ingestão de ?-galactosidase em formas farmacêuticas. Neste trabalho avaliou-se a capacidade de hidrólise de ?-galactosidase produzida por Kluyveromyces lactis e Aspergillus oryzae simulando as condições do trato gastrintestinal humano. O teste foi realizado nas temperaturas ótimas de ação para cada enzima, 40 e 55°C, respectivamente, e na temperatura corpórea humana (37°C), nas concentrações de 1,5; 3,0 e 5,0 g/L para a enzima de Aspergillus oryzae ou mL/L para a de Kluyveromyces lactis. Na simulação da condição estomacal humana (pH 2), ambas enzimas foram totalmente inativadas. Quando as enzimas foram submetidas às condições simuladas do intestino delgado (pH 7,4), observou-se hidrólise da lactose, porém, a 37°C, a porcentagem foi menor do que a observada nas temperaturas ótimas de cada enzima. A enzima de K. lactis nas concentrações de 1,5; 3,0 e 5,0 mL/L apresentou hidrólise de 76,63%, 88,91% e 94,80% a 40°C e 55,99%, 80,91% e 81,53%, a 37°C, respectivamente. Nas concentrações 1,5; 3,0 e 5,0 g/L, a porcentagem de hidrólise pela enzima de A. oryzae a 55°C foi de 7,11%, 16,18% e 21,29%. Para esta enzima, nessas concentrações, a hidrólise obtida a 37°C foi 8,4%, 11,85% e de 16,43%. Sob condições intestinais simuladas, a enzima de K. lactis apresentou maior eficiência na hidrólise da lactose quando comparada à enzima de A. oryzae. Considerando-se as etapas avaliadas neste estudo, observa-se que é extremamente necessário o uso de um revestimento entérico em cápsulas de ?-galactosidase, para que esta enzima seja liberada somente no intestino delgado, seu local de ação, não sofrendo, portanto, a ação do pH estomacal.(AU)


Assuntos
Humanos , Trato Gastrointestinal , Lactase/administração & dosagem , Intolerância à Lactose , Aspergillus oryzae/enzimologia , Kluyveromyces/enzimologia , beta-Galactosidase/análise
11.
Braz. j. microbiol ; 45(3): 873-883, July-Sept. 2014. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-727016

RESUMO

The mutant Penicillium chrysogenum strain dogR5, derived from strain AS-P-78, does not respond to glucose regulation of penicillin biosynthesis and β-galactosidase, and is partially deficient in D-glucose phosphorilating activity. We have transformed strain dogR5 with the (hexokinase) hxk2 gene from Saccharomyces cerevisiae. Transformants recovered glucose control of penicillin biosynthesis in different degrees, and acquired a hexokinase (fructose phosphorylating) activity absent in strains AS- P-78 and dogR5. Interestingly, they also recovered glucose regulation of β-galactosidase. On the other hand, glucokinase activity was affected in different ways in the transformants; one of which showed a lower activity than the parental dogR5, but normal glucose regulation of penicillin biosynthesis. Our results show that Penicillium chrysogenum AS-P-78 and dogR5 strains lack hexokinase, and suggest that an enzyme with glucokinase activity is involved in glucose regulation of penicillin biosynthesis and β-galactosidase, thus signaling glucose in both primary and secondary metabolism; however, catalytic and signaling activities seem to be independent.


Assuntos
Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Glucose/metabolismo , Hexoquinase/metabolismo , Penicilinas/biossíntese , Penicillium chrysogenum/genética , Penicillium chrysogenum/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Hexoquinase/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Transformação Genética , beta-Galactosidase/biossíntese
12.
Rev. Esc. Enferm. USP ; 48(spe): 74-79, 08/2014. tab
Artigo em Inglês | LILACS, BDENF - Enfermagem | ID: lil-731303

RESUMO

Affective, cognitive and behavioral components affect nurses´ attitudes to include families in the care processes. The purpose of this study was to investigate the attitudes of nurses about the importance of including families in nursing care. Data collection was performed in pediatric and maternal-child unit of a Brazilian university hospital. A sample of 50 nurses completed the Portuguese version of the instrument Families’Importance in Nursing Care-Nurses’ Attitudes (FINC-NA). The results indicated that nurses have supportive attitudes regarding families participation in nursing care. Attitudes of lower support for involving families in nursing care were found among nurses with older age, more time in the profession and who had no previous contact with contents related to Family Nursing. The application of the instrument in other contexts of assistance may help to illuminate important aspects of the challenges to implementing a family-centered approach in clinical practice.



.


El propósito de este estudio fue identificar las actitudes de los enfermeros sobre la importancia de incluir a las familias en el cuidado de enfermería. La recolección de datos se llevó a cabo en las unidades de pediatría y materno-infantil de un hospital universitario brasileño. Una muestra de 50 enfermeras completó la versión en portugués del el instrumento Families’ Importance in Nursing Care-Nurses’ Attitudes (FINC-NA). Los resultados indicaron las puntuaciones más altas en dimensiones indicativas de actitudes de apoyo a la participación de las familias en el cuidado. Enfermeras con más tiempo en la profesión y que no tenían conocimiento previo de enfermería de familia tuvieron puntuaciones que indican actitudes de menor apoyo para involucrar a las familias en el cuidado de enfermería. La aplicación de este instrumento en otro tipo de asistencia contextos puede ayudar a iluminar aspectos importantes de los desafíos para la implementación de un enfoque centrado en la familia, en la práctica clínica.
.


Objetivo Identificar as atitudes dos enfermeiros sobre a importância de incluir as famílias nos cuidados de enfermagem. Método Estudo de abordagem quantitativa descritiva, cuja coleta de dados foi realizada em unidades de pediatria e materno-infantil de um hospital universitário brasileiro. Uma amostra de 50 enfermeiros completou a versão em português da escala Families Importance in Nursing Care-Nurses Attitudes (FINC-NA). Resultados Indicaram escores mais elevados em dimensões indicativas de atitudes de apoio sobre a participação das famílias no cuidado de enfermagem. Enfermeiros com mais tempo na profissão e que não tiveram conhecimento prévio de enfermagem da família apresentaram escores indicativos de atitudes de menor apoio para envolver as famílias no cuidado de enfermagem. Conclusão A aplicação desse instrumento em outros contextos de assistência poderá contribuir para iluminar importantes aspectos relacionados aos desafios para a implementação de uma abordagem centrada na família na prática clínica e subsidiar o desenvolvimento de pesquisas mais amplas.
 .


Assuntos
Azoarcus/metabolismo , Coenzima A Ligases/genética , Fenilacetatos/metabolismo , Aerobiose , Azoarcus/genética , Coenzima A Ligases/metabolismo , Immunoblotting , Mutação , Proteínas Recombinantes de Fusão/genética , Análise de Sequência de DNA , beta-Galactosidase/genética
13.
Rev. Esc. Enferm. USP ; 48(spe): 16-22, 08/2014. tab
Artigo em Inglês | LILACS, BDENF - Enfermagem | ID: lil-731304

RESUMO

Objective To analyze the determinants of emergency contraception non-use among women in unplanned and ambivalent pregnancies. Method Cross-sectional study with a probabilistic sample of 366 pregnant women from 12 primary health care units in the city of São Paulo, Brazil. A multinomial logistic regression was performed, comparing three groups: women who used emergency contraception to prevent ongoing pregnancies (reference); women who made no use of emergency contraception, but used other contraceptive methods; and women who made no use of any contraceptive methods at all. Results Cohabitation with a partner was the common determinant of emergency contraception non-use. No pregnancy risk awareness, ambivalent pregnancies and no previous use of emergency contraception also contributed to emergency contraception non-use. Conclusion Apart from what is pointed out in the literature, knowledge of emergency contraception and the fertile period were not associated to its use. .


Objetivo Analizar los determinantes del no uso de la anticoncepción de emergencia entre las mujeres con embarazo no planeado o ambivalente. Método Estudio transversal en una muestra probabilística de 366 mujeres embarazadas de 12 Unidades Básicas de Salud de São Paulo. Mediante regresión logística multinomial, se comparó tres grupos de mujeres: aquellas que usaron la anticoncepción de emergencia para prevenir el embarazo en curso (referencia), aquellas que usaron algún método anticonceptivo, pero no la anticoncepción de emergência; y aquellas que no usaron ningún método. Resultados Los hallazgos mostraron que vivir com la pareja fue el determinante común del no uso de la anticoncepción de emergencia. No tener conciencia del riesgo de embarazo, estar en un embarazo ambivalente y nunca tener utilizado la anticoncepción de emergencia también fueron associados con su no uso para prevenir el embarazo en curso. Conclusión Contrariamente a lo que reporta la literatura, el conocimiento de la anticoncepción de emergencia y el período fértil no mostró asociación con el no uso. .


Objetivo Analisar os determinantes do não uso da anticoncepção de emergência entre mulheres com gravidez não planejada ou ambivalente. Método Estudo transversal com amostra probabilística de 366 gestantes de 12 Unidades Básicas de Saúde da cidade de São Paulo. Por meio de regressão logística multinomial, compararam-se três grupos de mulheres: as que usaram anticoncepção de emergência para prevenir a gravidez em curso (referência); as que usaram algum método contraceptivo, mas não anticoncepção de emergência; e as que não usaram nenhum método. Resultados Os achados mostraram que morar com o parceiro foi o determinante comum do não uso da anticoncepção de emergência. Não ter consciência do risco de engravidar, estar em uma gravidez ambivalente e nunca ter usado anticoncepção de emergência também foram associados ao seu não uso para prevenir a gravidez em curso. Conclusão Diferentemente do que relata a literatura, o conhecimento sobre anticoncepção de emergência e sobre o período fértil não mostrou qualquer associação ao não uso. .


Assuntos
Proteínas de Ligação a DNA , Escherichia coli/genética , Mapeamento de Interação de Proteínas/métodos , Técnicas do Sistema de Duplo-Híbrido , Bacteriófago lambda/genética , DNA Bacteriano/genética , RNA Polimerases Dirigidas por DNA/biossíntese , RNA Polimerases Dirigidas por DNA/genética , RNA Polimerases Dirigidas por DNA/fisiologia , Proteínas de Escherichia coli/biossíntese , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/fisiologia , Escherichia coli/enzimologia , Genes Reporter/genética , Fosforilação , Plasmídeos/biossíntese , Plasmídeos/genética , Regiões Promotoras Genéticas/genética , RNA Bacteriano/genética , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/fisiologia , Proteínas Repressoras/biossíntese , Proteínas Repressoras/genética , Proteínas Repressoras/fisiologia , Transcrição Gênica/genética , Transcrição Gênica/fisiologia , Proteínas Virais/biossíntese , Proteínas Virais/genética , Proteínas Virais/fisiologia , Proteínas Virais Reguladoras e Acessórias , beta-Galactosidase/biossíntese , beta-Lactamases/biossíntese
14.
Rev. cuba. pediatr ; 86(1): 103-107, abr.-jun. 2014.
Artigo em Espanhol | LILACS | ID: lil-709199

RESUMO

La gangliosidosis generalizada tipo 1 es una enfermedad de acúmulo lisosomal producida por mutaciones en el gen de la enzima b-galactosidasa, caracterizada fundamentalmente por toma del sistema nervioso central, la visceromegalia, disostosis ósea y dimorfismo facial. Se presenta el caso de un lactante varón, hijo de padres no consanguíneos, de 5 meses de edad, Apgar 6/8 debido a hipoxia neonatal, con historia de múltiples ingresos por enfermedad diarreica e infecciones respiratorias. Es remitido a la Consulta de Genética Clínica por retardo del desarrollo psicomotor, macrocráneo y hepatomegalia, además de máculas hipercrómicas en piel. En el examen físico se encontraron evidencias de una posible afectación por enfermedad metabólica lisosomal. Entre las enfermedades a descartar estaban la galactosialidosis, de características clínicas similares, y la enfermedad de Morquio, con diferente presentación clínica pero idéntico defecto enzimático


Generalized or GM 1 gangliosidosis is a lysosomal storage disease caused by mutations in the enzyme b-galactosidase gene, mainly characterized by affecting the central nervous system, visceromegalia, osseous dysostosis and facial dimorphism. This is the case of a male nursling born to non-consanguineous parents, 5 months of age, Apgar index of 6/8 due to neonatal hypoxia, with a history of several admissions to hospital because of diarrheal disease and respiratory infections. He was referred to the clinical genetic service since he presented with retarded psychomotor development, macrocrania and hepatomegalia, in addition to hyperchromic skin spots. The physical exam found evidence of possible effects by lysosomal metabolic disease. Among the diseases to be ruled out for the diagnosis were galactosialidosis of similar clinical characteristics and Morquio B disease with different clinical presentation but identical enzymatic deficiency


Assuntos
Humanos , Masculino , Lactente , Doenças por Armazenamento dos Lisossomos/complicações , Gangliosidose GM1 , beta-Galactosidase/genética , Relatos de Casos
15.
Braz. j. microbiol ; 45(2): 595-601, Apr.-June 2014. tab
Artigo em Inglês | LILACS | ID: lil-723123

RESUMO

A transconjugant of Azotobacter chroococcum Mac 27 tagged with lac Z(A. chroococcum Mac27 L) was found to possess high levels of β-galactosidase activity constitutively.Further, the lac Z marker was found to be stably integrated into the chromosome of the A. chroococcum Mac 27 and did not have any adverse effect on growth, nitrogen fixation and excretion of ammonia. A quick method to determine the viable cell number in broth culture and carrier based inoculants has been developed on the basis of β-galactosidase assay. It was found that there was a direct relationship between the number of cell as determined by standard plate count and intensity of colour that developed upon degradation of ONPG due to β-galactosidase activity .The method was found to be sensitive enough to determine 1.7 x 10(6) CFU mL-1 in broth culture as well as carrier based Azotobacter inoculants. Further, it was observed that when A. chroococcum Mac27 L was inoculated on Brassica campestris, it could be detected in the presence of other bacteria capable of growing on Burks agar medium containing X-gal on the basis of lac Z genetic marker.


Assuntos
Azotobacter/isolamento & purificação , Carga Bacteriana/métodos , Genes Reporter , beta-Galactosidase/análise , Brassica rapa/microbiologia , Sensibilidade e Especificidade , beta-Galactosidase/genética
16.
Biol. Res ; 47: 1-11, 2014. graf, tab
Artigo em Inglês | LILACS | ID: biblio-950746

RESUMO

BACKGROUND: Accumulating evidence indicates that reactive oxygen species (ROS) are an important etiological factor for the induction of dermal papilla cell senescence and hair loss, which is also known alopecia. Arctiin is an active lignin isolated from Arctium lappa and has anti-inflammation, anti-microbial, and anti-carcinogenic effects. In the present study, we found that arctiin exerts anti-oxidative effects on human hair dermal papilla cells (HHDPCs). RESULTS: To better understand the mechanism, we analyzed the level of hydrogen peroxide (H2O2)-induced cytotoxicity, cell death, ROS production and senescence after arctiin pretreatment of HHDPCs. The results showed that arctiin pretreatment significantly inhibited the H2O2-induced reduction in cell viability. Moreover, H2O2-induced sub-G1 phase accumulation and G2 cell cycle arrest were also downregulated by arctiin pretreatment. Interestingly, the increase in intracellular ROS mediated by H2O2 was drastically decreased in HHDPCs cultured in the presence of arctiin. This effect was confirmed by senescence associated-beta galactosidase (SA-ß-gal) assay results; we found that arctiin pretreatment impaired H2O2-induced senescence in HHDPCs. Using microRNA (miRNA) microarray and bioinformatic analysis, we showed that this anti-oxidative effect of arctiin in HHDPCs was related with mitogen-activated protein kinase (MAPK) and Wnt signaling pathways. CONCLUSIONS: Taken together, our data suggest that arctiin has a protective effect on ROS-induced cell dysfunction in HHDPCs and may therefore be useful for alopecia prevention and treatment strategies.


Assuntos
Humanos , Envelhecimento/metabolismo , Espécies Reativas de Oxigênio/antagonistas & inibidores , Folículo Piloso/efeitos dos fármacos , MicroRNAs/metabolismo , Furanos/farmacologia , Glucosídeos/farmacologia , Envelhecimento/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , beta-Galactosidase/análise , Folículo Piloso/citologia , Folículo Piloso/metabolismo , Derme/citologia , Derme/efeitos dos fármacos , Derme/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , MicroRNAs/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia
17.
Braz. j. microbiol ; 44(4): 1067-1074, Oct.-Dec. 2013. graf, tab
Artigo em Inglês | LILACS | ID: lil-705252

RESUMO

The aim of our study was to select the optimal operating conditions to permeabilize Kluyveromyces lactis cells using ethanol as a solvent as an alternative to cell disruption and extraction. Cell permeabilization was carried out by a non-mechanical method consisting of chemical treatment with ethanol, and the results were expressed as β-galactosidase activity. Experiments were conducted under different conditions of ethanol concentration, treatment time and temperature according to a central composite rotatable design (CCRD), and the collected results were then worked out by response surface methodology (RSM). Cell permeabilization was improved by an increase in ethanol concentration and simultaneous decreases in the incubation temperature and treatment time. Such an approach allowed us to identify an optimal range of the independent variables within which the β-galactosidase activity was optimized. A maximum permeabilization of 2,816 mmol L-1 oNP min-1 g-1 was obtained by treating cells with 75.0% v/v of ethanol at 20.0 °C for 15.0 min. The proposed methodology resulted to be effective and suited for K. lactis cells permeabilization at a lab-scale and promises to be of possible interest for future applications mainly in the food industry.


Assuntos
Membrana Celular/efeitos dos fármacos , Etanol/toxicidade , Kluyveromyces/efeitos dos fármacos , Permeabilidade/efeitos dos fármacos , Membrana Celular/fisiologia , Kluyveromyces/fisiologia , Modelos Estatísticos , Temperatura , Fatores de Tempo , beta-Galactosidase/análise
18.
Braz. j. med. biol. res ; 45(12): 1135-1140, Dec. 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-659653

RESUMO

Azospirillum brasilense is a diazotroph that associates with important agricultural crops and thus has potential to be a nitrogen biofertilizer. The A. brasilense transcription regulator NifA, which seems to be constitutively expressed, activates the transcription of nitrogen fixation genes. It has been suggested that the nitrogen status-signaling protein GlnB regulates NifA activity by direct interaction with the NifA N-terminal GAF domain, preventing the inhibitory effect of this domain under conditions of nitrogen fixation. In the present study, we show that an N-terminal truncated form of NifA no longer required GlnB for activity and lost regulation by ammonium. On the other hand, in trans co-expression of the N-terminal GAF domain inhibited the N-truncated protein in response to fixed nitrogen levels. We also used pull-down assays to show in vitro interaction between the purified N-terminal GAF domain of NifA and the GlnB protein. The results showed that A. brasilense GlnB interacts directly with the NifA N-terminal domain and this interaction is dependent on the presence of ATP and 2-oxoglutarate.


Assuntos
Trifosfato de Adenosina/metabolismo , Azospirillum brasilense/enzimologia , Proteínas de Bactérias/metabolismo , Ácidos Cetoglutáricos/metabolismo , Fatores de Transcrição/metabolismo , beta-Galactosidase/metabolismo , Azospirillum brasilense/metabolismo , Vetores Genéticos , Plasmídeos
19.
Clinics ; 67(2): 135-143, 2012. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-614637

RESUMO

OBJECTIVE: Human diploid fibroblasts undergo a limited number of cellular divisions in culture and progressively reach a state of irreversible growth arrest, a process termed cellular aging. The beneficial effects of vitamin E in aging have been established, but studies to determine the mechanisms of these effects are ongoing. This study determined the molecular mechanism of γ-tocotrienol, a vitamin E homolog, in the prevention of cellular aging in human diploid fibroblasts using the expression of senescence-associated genes. METHODS: Primary cultures of young, pre-senescent, and senescent fibroblast cells were incubated with γ-tocotrienol for 24 h. The expression levels of ELN, COL1A1, MMP1, CCND1, RB1, and IL6 genes were determined using the quantitative real-time polymerase chain reaction. Cell cycle profiles were determined using a FACSCalibur Flow Cytometer. RESULTS: The cell cycle was arrested in the G0/G1 phase, and the percentage of cells in S phase decreased with senescence. CCND1, RB1, MMP1, and IL6 were upregulated in senescent fibroblasts. A similar upregulation was not observed in young cells. Incubation with γ-tocotrienol decreased CCND1 and RB1 expression in senescent fibroblasts, decreased cell populations in the G0/G1 phase and increased cell populations in the G2/M phase. γ-Tocotrienol treatment also upregulated ELN and COL1A1 and downregulated MMP1 and IL6 expression in young and senescent fibroblasts. CONCLUSION: γ-Tocotrienol prevented cellular aging in human diploid fibroblasts, which was indicated by the modulation of the cell cycle profile and senescence-associated gene expression.


Assuntos
Humanos , Antioxidantes/farmacologia , Senescência Celular/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Cromanos/farmacologia , Fibroblastos/efeitos dos fármacos , Vitamina E/análogos & derivados , beta-Galactosidase/análise , Análise de Variância , Biomarcadores/análise , Células Cultivadas , Senescência Celular/genética , Ciclo Celular/genética , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Ciclina D1/genética , Ciclina D1/metabolismo , Diploide , Fibroblastos/citologia , Fibroblastos/metabolismo , /genética , /metabolismo , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 1 da Matriz/metabolismo , RNA Mensageiro/metabolismo , Proteína do Retinoblastoma/genética , Proteína do Retinoblastoma/metabolismo , Regulação para Cima/efeitos dos fármacos , Vitamina E/farmacologia , beta-Galactosidase/metabolismo
20.
Electron. j. biotechnol ; 14(6): 9-9, Nov. 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-640526

RESUMO

Whey is a co-product of processes for the production of cheese and casein that retains most of the lactose content in milk. World production of whey is estimated around 200 million tons per year with an increase rate of about 2 percent/per year. Milk production is seasonal, so surplus whey is unavoidable. Traditionally, whey producers have considered it as a nuisance and strategies of whey handling have been mostly oriented to their more convenient disposal. This vision has been steadily evolving because of the upgrading potential of whey major components (lactose and whey proteins), but also because of more stringent regulations of waste disposal. Only the big cheese manufacturing companies are in the position of implementing technologies for their recovery and upgrading, so there is a major challenge in incorporating medium and small size producers to a platform of whey utilization, conciliating industrial interest with environmental protection within the framework of sustainable development. Within this context, among the many technological options for whey upgrading, transformation of whey components by enzyme biocatalysis appears as prominent. In fact, enzymes are green catalysts that can perform a myriad of transformation reactions under mild conditions and with strict specificity, so reducing production costs and environmental burden. This review pretends to highlight the impact of biocatalysis within a platform of whey upgrading. Technological options are shortly reviewed and then an in-depth and critical appraisal of enzyme technologies for whey upgrading is presented, with a special focus on newly developed enzymatic processes of organic synthesis, where the added value is high, being then a powerful driving force for industrial implementation.


Assuntos
Lactose , Leite/enzimologia , Oligossacarídeos/metabolismo , Prebióticos , beta-Galactosidase/metabolismo , Biocatálise , Esterificação , Enzimas/metabolismo
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