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

RESUMEN

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)


Asunto(s)
Animales , Ratas , Oligosacáridos/metabolismo , Osteogénesis/fisiología , Calcio de la Dieta/farmacocinética , Fósforo Dietético/farmacocinética , Absorción Intestinal/fisiología , Lactosa/metabolismo , Magnesio/farmacocinética , Tibia/anatomía & histología , Yogur/análisis , Calcio de la Dieta/metabolismo , Absorciometría de Fotón , Densidad Ósea , Interpretación Estadística de Datos , Fósforo Dietético/metabolismo , beta-Galactosidasa/síntesis química , Ratas Wistar , Lactobacillus delbrueckii/aislamiento & purificación , Fémur/anatomía & histología , Intestino Grueso/anatomía & histología , Magnesio/metabolismo , Valor Nutritivo
2.
Chinese Journal of Medical Genetics ; (6): 537-541, 2022.
Artículo en Chino | WPRIM | ID: wpr-928454

RESUMEN

OBJECTIVE@#To explore the genotype-phenotype correlation of a case with GM1-gangliosidosis caused by compound heterogenic variants in GLB1.@*METHODS@#Genomic DNA was extracted from peripheral blood samples from the patient and her parents. Trio-based whole-exome sequencing (WES) was performed for the family and suspected mutation was verified by Sanger sequencing.@*RESULTS@#The proband, a 2-year-3-month old Chinese girl, presented with psychomotor deterioration, absent speech, intellectual disabilities and behavior problem. Trio-based WES has identified compound heterozygosity for 2 variants in the GLB1 gene: NM_000404.2:c.1343A>T, p.Asp448Val and c.1064A>C, p.Gln355Pro (GRCh37/hg19),which was inherited from the mother and father, respectively. Homozygous or compound heterozygous pathogenic variants in GLB1, encoding β-galactosidase, are responsible for GM1-gangliosidosis,an autosomal recessive lysosomal storage disorder characterized by variable degrees of neurodegeneration and skeletal abnormalities. The p.Asp448Val variant has been classified as pathogenic for GM1 gangliosidosis in medical literatures for the reason that functional studies demonstrated that expression of the p.Asp448Val variant in COS-1 cells resulted in no detectable β-galactosidase activity compared to wild type GLB1. The p.Gln355Pro variant has not been reported in literatures or database. The variant is highly conserved residue (PM1), and was not found in either the Genome Aggregation Database or the 1000 Genomes Project (PM2) and was predicted to have a deleterious effect on the gene product by multiple in silico prediction tools (PP3). Next, the β-galactosidase activity of the patient's peripheral blood leukocytes was determined by fluorescent method. The result was 0.0 nmol/mg. It showed that the p.Gln355Pro variant also resulted in loss of β-galactosidase activity, thus the variant was classified into clinical pathogenic variant.@*CONCLUSION@#Our study expands the mutational spectrum of the GLB1 gene and provides genetic counseling for the family.


Asunto(s)
Femenino , Humanos , Pueblo Asiatico/genética , China , Gangliósido G(M1) , Gangliosidosis GM1/genética , Mutación , beta-Galactosidasa/genética
4.
Electron J Biotechnol ; 49: 14-21, Jan. 2021. graf, tab
Artículo en Inglés | LILACS | ID: biblio-1291625

RESUMEN

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.


Asunto(s)
Oligosacáridos/biosíntesis , beta-Galactosidasa/metabolismo , Pantoea , Lactosa/metabolismo , Proteínas Recombinantes , Industria Lechera , Suero Lácteo
5.
Chinese Journal of Biotechnology ; (12): 321-330, 2021.
Artículo en Chino | WPRIM | ID: wpr-878565

RESUMEN

To construct a prokaryotic promoter report system with wide applicability, a series of pFGH reporter vectors based on lacZ gene and pUC replicon were constructed from plasmid pFLX107 through the replacement of multiple cloning sites and sequence modifications. The plasmid with the lowest background activity was selected as the final report system with the lacZ gene deletion strain MC4100 as the host bacterium, following by testing with inducible promoter araBAD and the constitutive promoter rpsM. The background activity of pFGH06 was significantly lower than that of other plasmids of the same series, and even lower than that of reference plasmid pRCL at 28 °C (P<0.01). Further evaluation tests show that the plasmid pFGH06 could be used to clone and determine the activity of inducible promoter or constitutive promoter, and the complete recognition of the target promoter could be achieved through blue-white selection in the simulation test of promoter screening. Compared with the reported prokaryotic promoter report systems, pFGH06 has the advantages of smaller size, more multiple clone sites, adjustable background activity, high efficiency of promoter screening and recognition, thus with a wide application prospect.


Asunto(s)
Clonación Molecular , Escherichia coli/genética , Genes Reporteros/genética , Vectores Genéticos/genética , Operón Lac/genética , Plásmidos/genética , beta-Galactosidasa/genética
6.
Braz. arch. biol. technol ; 64: e21180747, 2021. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1345490

RESUMEN

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.


Asunto(s)
beta-Galactosidasa , Industria Lechera , Enzimas , Nanopartículas
7.
Rev. chil. nutr ; 47(1): 14-21, feb. 2020. graf
Artículo en Español | LILACS | ID: biblio-1092739

RESUMEN

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.


Asunto(s)
Desnaturalización Proteica , Temperatura , Reacción de Maillard , Leche/química , Lactosa/química , Tratamiento Térmico , beta-Galactosidasa , Color , Glucosa/análisis , Hidrólisis
8.
Electron. j. biotechnol ; 40: 78-83, July. 2019. tab, graf, ilus
Artículo en Inglés | LILACS | ID: biblio-1053493

RESUMEN

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.


Asunto(s)
Método de Montecarlo , Enzimas/metabolismo , Hidrólisis , Lactosa/metabolismo , Factores de Tiempo , Cinética , beta-Galactosidasa/metabolismo , Enzimas Inmovilizadas , Galactosa/metabolismo
9.
Journal of Zhejiang University. Science. B ; (12): 264-272, 2019.
Artículo en Inglés | WPRIM | ID: wpr-1010456

RESUMEN

β-Glucosidase activity assays constitute an important indicator for the early diagnosis of neonatal necrotizing enterocolitis and qualitative changes in medicinal plants. The drawbacks of the existing methods are high consumption of both time and reagents, complexity in operation, and requirement of expensive instruments and highly trained personnel. The present study provides a simplified, highly selective, and miniaturized glucometer-based strategy for the detection of β-glucosidase activity. Single-factor experiments showed that optimum β-glucosidase activity was exhibited at 50 °C and pH 5.0 in a citric acid-sodium citrate buffer when reacting with 0.03 g/mL salicin for 30 min. The procedure for detection was simplified without the need of a chromogenic reaction. Validation of the analytical method demonstrated that the accuracy, precision, repeatability, stability, and durability were good. The linear ranges of β-glucosidase in a buffer solution and rat serum were 0.0873-1.5498 U/mL and 0.4076-2.9019 U/mL, respectively. The proposed method was free from interference from β-dextranase, snailase, β-galactosidase, hemicellulase, and glucuronic acid released by baicalin. This demonstrated that the proposed assay had a higher selectivity than the conventional dinitrosalicylic acid (DNS) assay because of the specificity for salicin and unique recognition of glucose by a personal glucose meter. Miniaturization of the method resulted in a microassay for β-glucosidase activity. The easy-to-operate method was successfully used to detect a series of β-glucosidases extracted from bitter almonds and cultured by Aspergillus niger. In addition, the simplified and miniaturized glucometer-based assay has potential application in the point-of-care testing of β-glucosidase in many fields, including medical diagnostics, food safety, and environmental monitoring.


Asunto(s)
Animales , Ratas , Aspergillus niger , Calibración , Celulasa/análisis , Química Clínica/métodos , Dextranasa/análisis , Enterocolitis Necrotizante/diagnóstico , Diseño de Equipo , Flavonoides/análisis , Glucosa/análisis , Ácido Glucurónico/análisis , Glucuronidasa/análisis , Glicósido Hidrolasas/análisis , Concentración de Iones de Hidrógeno , Modelos Lineales , Complejos Multienzimáticos/análisis , Plantas Medicinales , Poligalacturonasa/análisis , Reproducibilidad de los Resultados , beta-Galactosidasa/análisis , beta-Glucosidasa/análisis
10.
Chinese Journal of Medical Genetics ; (6): 128-131, 2019.
Artículo en Chino | WPRIM | ID: wpr-775797

RESUMEN

OBJECTIVE@#To explore the genetic cause for a child with growth retardation by next generation sequencing (NGS).@*METHODS@#Clinical data of the patient was collected. Peripheral venous blood samples were taken from the neonate and his parents. Targeted capturing and NGS were carried out to detect mutations of genes associated with inborn errors of metabolism. Suspected mutations were validated by Sanger sequencing.@*RESULTS@#The 15-month-old female patient was admitted to hospital for growth retardation for 4 months. Hypomyelination was found upon cranium MRI. Genetic testing revealed two novel insertional mutations in the GLB1 gene in the patient, namely c.2006-2007insT and c.475-476 insGGTCC.@*CONCLUSION@#The c.2006-2007insT and c.475-476 insGGTCC mutations of the GLB1 gene probably underlie the GM1 gangliosidosis resulting in the growth retardation in the child.


Asunto(s)
Femenino , Humanos , Lactante , Recién Nacido , Gangliosidosis GM1 , Genética , Mutación , Linaje , beta-Galactosidasa , Genética
11.
Chinese Journal of Contemporary Pediatrics ; (12): 71-76, 2019.
Artículo en Chino | WPRIM | ID: wpr-774125

RESUMEN

GM1 gangliosidosis is an autosomal recessive disorder caused by galactosidase beta1 (GLB1) gene variants which affect the activity of β-galactosidase (GLB). GLB dysfunction causes abnormalities in the degradation of GM1 and its accumulation in lysosome. This article reports the clinical and genetic features of a child with GM1 gangliosidosis. The girl, aged 2 years and 5 months, was referred to the hospital due to motor developmental regression for more than one year. Physical examination showed binocular deflection and horizontal nystagmus, but no abnormality was found on fundoscopy. The girl had increased muscular tone of the extremities, limitation of motion of the elbow, knee, and ankle joints, and hyperactive patellar tendon reflex. Blood biochemical examination showed a significant increase in aspartate aminotransferase. The 24-hour electroencephalographic monitoring detected frequent seizure attacks and diffuse θ wave activity, especially in the right hemisphere. Head magnetic resonance imaging showed thinner white matter in the periventricular region and diffuse high T2WI signal with unclear boundary. Three-dimensional reconstruction of white matter fiber tracts by diffusion tensor imaging showed smaller and thinner white matter fiber tracts, especially in the right hemisphere. Genetic analysis showed that the girl had compound heterozygous mutations of c.446C>T (p.Ser149Phe) and c.101T>C (p.Ile34Thr) in the GLB1 gene from her parents, among which c.101T>C (p.Ile34Thr) had not been reported in the literatures. The girl was finally diagnosed with GM1 gangliosidosis. Her conditions were not improved after antiepileptic treatment and rehabilitation training for 2 months.


Asunto(s)
Femenino , Humanos , Lactante , Imagen de Difusión Tensora , Gangliosidosis GM1 , Genética , Mutación , Virulencia , beta-Galactosidasa , Genética
12.
Journal of Zhejiang University. Science. B ; (12): 630-642, 2018.
Artículo en Inglés | WPRIM | ID: wpr-1010400

RESUMEN

The storage and transportation of raw milk at low temperatures promote the growth of psychrotrophic bacteria and the production of thermo-stable enzymes, which pose great threats to the quality and shelf-life of dairy products. Though many studies have been carried out on the spoilage potential of psychrotrophic bacteria and the thermo-stabilities of the enzymes they produce, further detailed studies are needed to devise an effective strategy to avoid dairy spoilage. The purpose of this study was to explore the spoilage potential of psychrotrophic bacteria from Chinese raw milk samples at both room temperature (28 °C) and refrigerated temperature (7 °C). Species of Yersinia, Pseudomonas, Serratia, and Chryseobacterium showed high proteolytic activity. The highest proteolytic activity was shown by Yersinia intermedia followed by Pseudomonas fluorescens (d). Lipolytic activity was high in isolates of Acinetobacter, and the highest in Acinetobacter guillouiae. Certain isolates showed positive β-galactosidase and phospholipase activity. Strains belonging to the same species sometimes showed markedly different phenotypic characteristics. Proteases and lipases produced by psychrotrophic bacteria retained activity after heat treatment at 70, 80, or 90 °C, and proteases appeared to be more heat-stable than lipases. For these reasons, thermo-stable spoilage enzymes produced by a high number of psychrotrophic bacterial isolates from raw milk are of major concern to the dairy industry. The results of this study provide valuable data about the spoilage potential of bacterial strains in raw milk and the thermal resistance of the enzymes they produce.


Asunto(s)
Animales , Bacterias/genética , Proteínas Bacterianas/química , Biopelículas , Frío , Productos Lácteos , Endopeptidasas/química , Estabilidad de Enzimas , Microbiología de Alimentos , Calor , Lipasa/química , Leche/microbiología , Péptido Hidrolasas/química , Fosfolipasas/química , ARN Ribosómico 16S/genética , Alimentos Crudos/microbiología , beta-Galactosidasa/química
13.
Electron. j. biotechnol ; 27: 37-43, May. 2017. tab, ilus, graf
Artículo en Inglés | LILACS | ID: biblio-1010283

RESUMEN

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.


Asunto(s)
Aspergillus niger/enzimología , beta-Galactosidasa/química , Especificidad por Sustrato , Cinética , Secuencia de Aminoácidos , Clonación Molecular , beta-Galactosidasa/genética , beta-Galactosidasa/metabolismo
14.
Acta sci., Biol. sci ; 38(2): 149-155, abr.-jun. 2016.
Artículo en Inglés | LILACS | ID: biblio-2531

RESUMEN

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.


Asunto(s)
Saccharomyces , beta-Galactosidasa , Permeabilidad , Saccharomyces , Levaduras , Biotecnología , Biocatálisis , Hidrólisis , Lactosa
15.
Biol. Res ; 49: 1-16, 2016. ilus, graf
Artículo en Inglés | LILACS | ID: biblio-950861

RESUMEN

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.


Asunto(s)
Humanos , Masculino , Senescencia Celular/fisiología , Fibroblastos/efectos de la radiación , Factores de Tiempo , Daño del ADN , Immunoblotting , Regulación hacia Abajo/efectos de la radiación , Regulación hacia Arriba/efectos de la radiación , Células Cultivadas , Análisis de Varianza , Senescencia Celular/efectos de la radiación , Senescencia Celular/genética , beta-Galactosidasa/metabolismo , Análisis de Secuencia de ARN , Perfilación de la Expresión Génica , Feto Abortado , Reparación del ADN/efectos de la radiación , Replicación del ADN/efectos de la radiación , Fibroblastos/fisiología , Rayos gamma , Pulmón
16.
Korean Journal of Veterinary Research ; : 75-84, 2016.
Artículo en Inglés | WPRIM | ID: wpr-20943

RESUMEN

Probiotics that are able to provide beneficial effects on animal health have become important ingredients of dog foods. This study was conducted to characterize the probiotic potentials of two strains, Lactobacillus reuteri BCLR-42 and Lactobacillus plantarum BCLP-51, that were derived from feces of healthy dogs and evaluated based on tolerance to low pH and bile acid, antimicrobial activities, enzyme profiles, sensitivity to antibiotics, and innate immune enhancing potentials. Both strains showed survival of more than 90% at pH 3 and 0.2% bile acid and exhibited broad antimicrobial activities against indicator bacteria. Moreover, both strains showed high sensitivity to antibiotics, except vancomycin, metronidazole, and gentamicin. The alkaline phosphatase was negligible (score 0), whereas they showed strong beta galactosidase activity (score range 5 or 3, respectively). The phagocytosis and oxidative burst activities of canine granulocytes were significantly enhanced in response to both strains. These results show that both strains have the capability to act as probiotics and the potential for application as ingredients in dog foods.


Asunto(s)
Animales , Perros , Fosfatasa Alcalina , Antibacterianos , Bacterias , beta-Galactosidasa , Bilis , Heces , Gentamicinas , Granulocitos , Concentración de Iones de Hidrógeno , Lactobacillus plantarum , Limosilactobacillus reuteri , Lactobacillus , Metronidazol , Fagocitosis , Probióticos , Estallido Respiratorio , Vancomicina
17.
Rev. ciênc. farm. básica apl ; 36(1)mar. 2015. tab
Artículo en Inglés | LILACS | ID: lil-761234

RESUMEN

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)


Asunto(s)
Humanos , Tracto Gastrointestinal , Lactasa/administración & dosificación , Intolerancia a la Lactosa , Aspergillus oryzae/enzimología , Kluyveromyces/enzimología , beta-Galactosidasa/análisis
18.
Braz. j. microbiol ; 45(3): 873-883, July-Sept. 2014. ilus, graf, tab
Artículo en Inglés | LILACS | ID: lil-727016

RESUMEN

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.


Asunto(s)
Regulación Fúngica de la Expresión Génica/efectos de los fármacos , Glucosa/metabolismo , Hexoquinasa/metabolismo , Penicilinas/biosíntesis , Penicillium chrysogenum/genética , Penicillium chrysogenum/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Hexoquinasa/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Transformación Genética , beta-Galactosidasa/biosíntesis
19.
Rev. Esc. Enferm. USP ; 48(spe): 74-79, 08/2014. tab
Artículo en Inglés | LILACS, BDENF | ID: lil-731303

RESUMEN

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.



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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.
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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.
 .


Asunto(s)
Azoarcus/metabolismo , Coenzima A Ligasas/genética , Fenilacetatos/metabolismo , Aerobiosis , Azoarcus/genética , Coenzima A Ligasas/metabolismo , Immunoblotting , Mutación , Proteínas Recombinantes de Fusión/genética , Análisis de Secuencia de ADN , beta-Galactosidasa/genética
20.
Rev. Esc. Enferm. USP ; 48(spe): 16-22, 08/2014. tab
Artículo en Inglés | LILACS, BDENF | ID: lil-731304

RESUMEN

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. .


Asunto(s)
Proteínas de Unión al ADN , Escherichia coli/genética , Mapeo de Interacción de Proteínas/métodos , Técnicas del Sistema de Dos Híbridos , Bacteriófago lambda/genética , ADN Bacteriano/genética , ARN Polimerasas Dirigidas por ADN/biosíntesis , ARN Polimerasas Dirigidas por ADN/genética , ARN Polimerasas Dirigidas por ADN/fisiología , Proteínas de Escherichia coli/biosíntesis , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/fisiología , Escherichia coli/enzimología , Genes Reporteros/genética , Fosforilación , Plásmidos/biosíntesis , Plásmidos/genética , Regiones Promotoras Genéticas/genética , ARN Bacteriano/genética , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/fisiología , Proteínas Represoras/biosíntesis , Proteínas Represoras/genética , Proteínas Represoras/fisiología , Transcripción Genética/genética , Transcripción Genética/fisiología , Proteínas Virales/biosíntesis , Proteínas Virales/genética , Proteínas Virales/fisiología , Proteínas Reguladoras y Accesorias Virales , beta-Galactosidasa/biosíntesis , beta-Lactamasas/biosíntesis
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