Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 3.987
Filtrar
1.
Int. j. morphol ; 38(4): 1112-1119, Aug. 2020. tab, graf
Artigo em Inglês | LILACS (Américas) | ID: biblio-1124903

RESUMO

Monosodium glutamate (MSG) is a flavor enhancer widely used in the food industry, with obesogenic properties, in addition to causing alterations in the oral cavity. The aim of the study was to observe the morphofunctional changes in the parotid gland after the administration of MSG in rats. 18 newborn male Sprague Dawley rats were used, divided into three groups (Control group; MSG1 group: 4 mg/g weight of monosodium glutamate, 5 doses, kept for 8 weeks, and MSG2 group: 4 mg/g weight of MSG, 5 doses, kept for 16 weeks). The body mass index (BMI) was calculated, and the salivary flow, pH, a-amylase activity, Na, Cl, K and Ca were analyzed by quantitative analysis. After euthanasia by ketamine/xylazine overdose, parotid volume was analyzed and stereology was performed. MSG administration caused an increase in BMI and a decrease in parotid volume as well as a reduction in salivary flow and pH and an increase in a-amylase activity, also increasing the salivary sodium and chlorine levels. Alterations in the normal stereological parameters of the gland were observed. Exposure to MSG caused morphofunctional alterations at parotid gland.


El glutamato monosódico (MSG), es un potenciador del sabor ampliamente utilizado en la industria alimentaria. Diversos estudios han propuesto la relación entre éste y el desarrollo de obesidad, además de provocar alteraciones en la cavidad oral. El objetivo del estudio fue observar los cambios morfofuncionales a nivel de la glándula parótida, posterior a la administración de MSG en ratas. Se utilizaron 18 ratas neonatas Sprague Dawley machos, divididas en tres grupos según su tiempo de exposición y dosis a MSG (Grupo Control, Grupo MSG1: 4 mg/g peso de glutamato monosódico, 5 dosis, mantenidas 8 semanas, Grupo MSG2: 4 mg/g peso de MSG, 5 dosis, mantenidas 16 semanas. Fue calculado el índice de masa corporal (BMI), además de ser analizado el flujo salival, pH, actividad de α-amilasa, y Na, Cl, K y Ca mediante análisis semicuantitativo. Luego de la eutanasia por sobredosis de ketamina/xilasina, las glándulas parótidas fueron extraídas y analizado su volumen y fueron procesadas para histología, y estudio estereológico. La administración de MSG causó aumento en BMI y disminución del volumen parotídeo, además de disminución del flujo y pH salival, así como aumento en actividad de la a-amilasa, aumentando además los niveles de sodio y cloro salival. Fueron observadas alteraciones a nivel de los parámetros estereológicos normales de la glándula. La exposición a MSG causó alteraciones morfofuncionales a nivel parotídeo, observándose una disminución del volumen de la glándula, acompañado de alteraciones en el adenómero y conductos estriados de la glándula, implicados en la producción, secreción y modificación de la saliva, la cual se vio alterada, en el flujo, pH, y en sus componentes.


Assuntos
Animais , Masculino , Ratos , Glândula Parótida/efeitos dos fármacos , Glutamato de Sódio/administração & dosagem , Aromatizantes/administração & dosagem , Saliva/química , Sódio/análise , Glutamato de Sódio/farmacologia , Fatores de Tempo , Índice de Massa Corporal , Cloro/análise , Análise de Variância , Ratos Wistar , alfa-Amilases/análise , Aromatizantes/farmacologia , Concentração de Íons de Hidrogênio
2.
Electron. j. biotechnol ; 43: 23-31, Jan. 2020. ilus, graf
Artigo em Inglês | LILACS (Américas) | ID: biblio-1087514

RESUMO

Background: Hong Qu glutinous rice wine (HQGRW) is brewed under non-aseptic fermentation conditions, so it usually has a relatively high total acid content. The aim of this study was to investigate the dynamics of the bacterial communities and total acid during the fermentation of HQGRW and elucidate the correlation between total acid and bacterial communities. Results: The results showed that the period of rapid acid increase during fermentation occurred at the early stage of fermentation. There was a negative response between total acid increase and the rate of increase in alcohol during the early fermentation stage. Bacterial community analysis using high-throughput sequencing technology was found that the dominant bacterial communities changed during the traditional fermentation of HQGRW. Both principal component analysis (PCA) and hierarchical clustering analysis revealed that there was a great difference between the bacterial communities of Hong Qu starter and those identified during the fermentation process. Furthermore, the key bacteria likely to be associated with total acid were identified by Spearman's correlation analysis. Lactobacillus, unclassified Lactobacillaceae, and Pediococcus were found, which can make significant contributions to the total acid development (| r| N 0.6 with FDR adjusted P b 0.05), establishing that these bacteria can associate closely with the total acid of rice wine. Conclusions: This was the first study to investigate the correlation between bacterial communities and total acid during the fermentation of HQGRW. These findings may be helpful in the development of a set of fermentation techniques for controlling total acid.


Assuntos
Bactérias/isolamento & purificação , Vinho/microbiologia , Pediococcus/isolamento & purificação , Pediococcus/genética , Pediococcus/metabolismo , Fatores de Tempo , Acetobacter/isolamento & purificação , Acetobacter/genética , Acetobacter/metabolismo , Análise por Conglomerados , Análise de Sequência , Biologia Computacional , Análise de Componente Principal , Fermentação , Microbiota , Concentração de Íons de Hidrogênio , Lactobacillus/isolamento & purificação , Lactobacillus/genética , Lactobacillus/metabolismo
3.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-762459

RESUMO

BACKGROUND: The existing modified carbapenem inactivation methods (mCIMs) recommended by the CLSI for detecting carbapenemase production have not been applicable for Acinetobacter baumannii. We evaluated the influence of matrices used in mCIMs and CIMTris on the stability of the disks for detecting carbapenemase producers and suggested optimal mCIM conditions for detecting carbapenemase-producing A. baumannii. METHODS: Seventy-three A. baumannii isolates characterized for antimicrobial susceptibility and carbapenemase encoding genes were tested for carbapenemase production using mCIM and CIMTris. The influence of the matrices (Tryptic soy broth [TSB] and Tris-HCl) used in these methods on the stability of the meropenem (MEM) disk was also evaluated. The mCIM conditions were adjusted to enhance screening sensitivity and specificity for detecting carbapenemase-producing A. baumannii. RESULTS: The matrices had an impact on the stability of the MEM disk after the incubation period (two or four hrs). TSB nutrient broth is an appropriate matrix for mCIM compared with Tris-HCl pH 7.6, which leads to the loss of MEM activity in CIMTris. The sensitivity and the specificity of the optimal mCIM were both 100%. CONCLUSIONS: We established optimal mCIM conditions for simple, accurate, and reproducible detection of carbapenemase-producing A. baumannii.


Assuntos
Acinetobacter baumannii , Acinetobacter , Concentração de Íons de Hidrogênio , Programas de Rastreamento , Métodos , Sensibilidade e Especificidade
4.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-782519

RESUMO

Currently, the optimal resuscitation fluid remains debatable. Therefore, in the present study, we designed a trometamol-balanced solution (TBS) for use as a resuscitation fluid for hemorrhagic shock. Hemorrhagic shock was induced in 18 male Wistar-Kyoto rats, which were assigned to normal saline (NS), Ringer's solution (RS), and TBS groups. During the hemorrhagic state, their hemodynamic parameters were recorded using an Abbott i-STAT analyzer with the CG4+ cartridge (for pH, pressure of carbon dioxide, pressure of oxygen, total carbon dioxide, bicarbonate, base excess, oxygen saturation, and lactate), the CG6+ cartridge (for sodium, potassium, chloride, blood glucose, blood urea nitrogen, hematocrit, and hemoglobin), and enzyme-linked immunosorbent assay kits (calcium, magnesium, creatinine, aspartate aminotransferase, alanine aminotransferase, bilirubin, and albumin). Similar trends were found for the parameters of biochemistries, electrolytes, and blood gas, and they revealed no significant changes after blood withdrawal-induced hemorrhagic shock. However, the TBS group showed more effective ability to correct metabolic acidosis than the NS and RS groups. TBS was a feasible and safe resuscitation solution in this study and may be an alternative to NS and RS for resuscitation in hemorrhagic shock patients without liver damage.


Assuntos
Acidose , Alanina Transaminase , Animais , Aspartato Aminotransferases , Bilirrubina , Glicemia , Nitrogênio da Ureia Sanguínea , Dióxido de Carbono , Creatinina , Eletrólitos , Ensaio de Imunoadsorção Enzimática , Hematócrito , Hemodinâmica , Humanos , Concentração de Íons de Hidrogênio , Fígado , Magnésio , Masculino , Oxigênio , Potássio , Ratos , Ressuscitação , Choque Hemorrágico , Sódio
5.
Artigo em Coreano | WPRIM (Pacífico Ocidental) | ID: wpr-820823

RESUMO

OBJECTIVES: The aim of this study was to investigate the effects of some commercial calamansicontaining beverages on the sound surface of bovine teeth as well as the dental erosion inhibitory effects of calcium.METHODS: The pH and titratable acidity of six kinds of commercially available calamansi beverages were determined. Further, 3% calcium was added to the calamansi beverage Oranssi in the experimental group to confirm its dental erosion inhibitory effect. Jeju Samdasoo was used in the negative control group and Coca-Cola in the positive control group. After immersing the sound teeth specimens for 10 min, surface microhardness was measured using the Vickers hardness number (VHN), and surface changes in specimens were observed under a scanning electron microscope.RESULTS: The average pH of the commercial calamansi beverages was 2.54±0.22. After 10 min of treatment with each experimental beverage, the surface hardness difference (ΔVHN) was highest in the Coca-Cola group (−49.05±12.59), followed by the Oranssi calamansi group (−43.77±13.70), 3% calcium-added Oranssi calamansi group (−2.71±12.58), and Samdasoo group (14.03±20.79). There was no significant difference between the bottled water and calcium-added Oranssi calamansi groups or between the Coca-Cola and Oranssi calamansi groups (P>0.05). However, there was a significant difference in the surface hardness between the bottled water and CocaCola groups (P<0.05). On scanning electron microscopy, the Samdasoo group showed a smooth surface without any loss, but Coca-Cola and Oranssi calamansi groups showed a rough surface due to erosion. However, although fine cracks and porosities were seen in the calcium-added Oranssi calamansi group, surfaces in the group were much smoother than those in the Oranssi calamansi group.CONCLUSIONS: Calamansi beverages of low pH may cause corrosion of the tooth surface, and the addition of calcium to the calamansi beverages inhibits demineralization of the tooth surface. Therefore, it is necessary to consider the risk of dental erosion when drinking calamansi beverages of low pH.


Assuntos
Bebidas , Cálcio , Corrosão , Esmalte Dentário , Ingestão de Líquidos , Água Potável , Dureza , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Porosidade , Dente
6.
Braz. dent. sci ; 23(1): 1-7, 2020. tab
Artigo em Inglês | LILACS (Américas), BBO | ID: biblio-1049765

RESUMO

Objetivo: O objetivo deste estudo foi avaliar o efeito in vitro de águas aromatizadas no esmalte dental humano utilizando um método gravimétrico. Material e Métodos: As superfícies linguais dos molares inferiores foram utilizadas para obter amostras de esmalte. O esmalte (n = 3) foi lavado, seco, e posteriormente imerso em 6 diferentes águas aromatizadas com gás disponíveis na região, e avaliado periodicamente por até 9 dias através de análise gravimétrica. Além disso, as medições de pH das águas aromatizadas foram registradas. Resultados: Todas as águas aromatizadas testadas apresentaram valores de pH abaixo do pH crítico. Os testes t pareados demonstraram reduções significativas na massa média do grupo para todas as amostras de esmalte desde o primeiro dia após a imersão em água com sabor, em comparação com as medições de referência. Reduções adicionais na massa média continuaram até o nono dia de imersão. Conclusão: As águas aromatizadas são potencialmente erosivas para as amostras de esmalte humano, sendo o efeito erosivo cumulativo ao longo do tempo. (AU)


Objective: The aim of this study was to assess the in vitro effect of flavored waters on human tooth enamel using a gravimetric method. Lingual surfaces of lower molars were used to obtain enamel specimens. Material and Methods: Enamel (n=3) was washed and dried, immersed in 6 flavors of locally available flavored sparkling water and assessed using gravimetric analysis, periodically for up to 9 days. Additionally, pH measurements of the flavored waters were recorded. Results: All the tested flavored waters showed pH values below that of critical pH. Paired t-tests demonstrated significant reductions in the mean group mass for all enamel specimens from as early as day 1 after immersion in flavored water, compared to baseline measurements. Further reductions in mean mass continued up to day 9 of immersion. Conclusion: Flavored waters are potentially erosive to human enamel specimens with the erosive effect being cumulative over time. (AU)


Assuntos
Humanos , Erosão Dentária , Esmalte Dentário , Gravimetria , Água Carbonatada , Aromatizantes , Fatores de Tempo , Técnicas In Vitro , Água Carbonatada/análise , Concentração de Íons de Hidrogênio , Dente Molar
7.
Int. j. odontostomatol. (Print) ; 14(3): 442-447, 2020. tab, graf
Artigo em Inglês | LILACS (Américas) | ID: biblio-1114919

RESUMO

Dietary supplements are being consumed with an increasingly high frequency among sports practitioners, whether at professional and/or amateur level. The supplements contain some nutritional properties in their composition, so they can dissolute the hydroxyapatite crystals of the enamel and favor the process of dental corrosion. The objective was to measure the corrosive power of protein-based supplementation (Whey Protein), under conditions that resemble the use of the supplement by the athletes, increasing the ecological validity of the study. The teeth of the test group (TG) were placed in contact with the Whey protein solution and then exposed to artificial saliva. And the teeth of the control group (CG) were exposed only to artificial saliva. The analysis occurred in natural healthy molar teeth, so that each tooth of the TG was immersed in 50 mL of supplement for 1.5 minutes and then placed in contact with the artificial saliva for 30 seconds. The same procedure was performed 5 times a day for 30, 60, 90, 120, 150 and 180 days. Each group, in its time (TG0 to TG180), underwent analysis of superficial roughness with the aid of optical profilometer (Talysurf CCI®, 3D model). The control group (CG) did not change its superficial roughness. Half of the teeth of the test group (TG) suffered loss of enamel surface. The values, in micrometers, of surface loss of the TG samples were 1.21; 2.1; 2.0; 1.04; 0.97; 0.8; 0.53; 1.14; 1.9; 2.0; 1.66; 1.80. The dietary supplement (Whey protein®) may be a potential cause of the dental corrosion process, considering the demineralization of hydroxyapatite that occurs along with the surface enamel loss.


Los suplementos dietéticos se consumen con una frecuencia cada vez más alta entre los practicantes de deportes, sea a nivel profesional y / o aficionado. Los suplementos contienen algunas propiedades nutricionales en su composición, por lo que pueden disolver los cristales de hidroxiapatita del esmalte y favorecer el proceso de corrosión dental. El objetivo fue medir el poder corrosivo de la suplementación a base de proteínas (proteína de suero), en condiciones que se asemejan al uso del suplemento por parte de los atletas, aumentando la validez ecológica del estudio. Los dientes del grupo de prueba (TG) se pusieron en contacto con la solución de proteína de suero y luego se expusieron a saliva artificial. Y los dientes del grupo de control (CG) estuvieron expuestos solo a saliva artificial. El análisis se realizó en dientes molares sanos naturales, cada diente del TG se sumergió en 50 ml de suplemento durante 1,5 minutos y luego se puso en contacto con la saliva artificial durante 30 segundos. El mismo procedimiento se realizó 5 veces al día durante 30, 60, 90, 120, 150 y 180 días. Cada grupo, en su momento (TG0 a TG180), se sometió a un análisis de rugosidad superficial con la ayuda de un perfilómetro óptico (Talysurf CCI®, modelo 3D). El grupo de control (CG) no cambió su rugosidad superficial. La mitad de los dientes del grupo de prueba (TG) sufrieron pérdida de la superficie del esmalte. Los valores, en micrómetros, de pérdida de superficie de las muestras de TG fueron 1.21; 2.1; 2,0; 1.04; 0,97; 0.8; 0,53; 1.14; 1.9; 2,0; 1,66; 1.80. El suplemento dietético (Whey protein®) puede ser una causa potencial del proceso de corrosión dental, considerando la desmineralización de la hidroxiapatita que ocurre junto con la pérdida de esmalte superficial.


Assuntos
Humanos , Esportes , Proteínas na Dieta/efeitos adversos , Desmineralização do Dente/induzido quimicamente , Suplementos Nutricionais/efeitos adversos , Saliva/química , Técnicas In Vitro , Projetos Piloto , Grupos Controle , Durapatita , Corrosão , Corrosão Dentária , Concentração de Íons de Hidrogênio
8.
Rev. cient. odontol ; 7(2): 23-32, jul.-dic. 2019. tab
Artigo em Espanhol | LILACS (Américas) | ID: biblio-1046583

RESUMO

Objetivo: Determinar la relación entre el pH salival y la prevalencia de caries dental en escolares de 6 a 12 años de la ciudad de Lima. Metodología: Estudio transversal desarrollado en 129 escolares de la institución educativa San Gabriel, del distrito de Villa María del Triunfo, en 2017. Se obtuvieron las mediciones del pH salival en los pacientes mediante el uso del pH-metro, asistido por tiras de papel y se evaluó la presencia de caries dental mediante el método CPO-D. También se evaluaron las características de sexo y edad de todos los pacientes. La estadística emplea las pruebas de Chi-cuadrado y se trabajó a un nivel de significancia de p < 0,05. Resultados: Se encontró una prevalencia de caries dental del 85,3% en escolares entre los 6 y 12 años. La prevalencia de caries según el género fue del 45,7% en niñas y el 39,5% en varones. No se encontró asociación estadísticamente significativa entre el género y la prevalencia de caries dental (p = 0,935). El 55% del grupo muestral presentó un pH ácido; el 41,1%, un pH neutro, y el 3,9%, un pH alcalino. Se determinó la existencia de una asociación estadísticamente significativa entre pH salival y caries dental (p < 0,001). Conclusiones: Existe una relación directa entre el pH salival y la prevalencia de caries dental. Se calculó que el 95,8% de los pacientes con un pH salival ácido presentaron caries dental. (AU)


Objective: To determine the relationship between the salivary pH and the prevalence of dental caries in school children between the ages of 6 and 12 in the city of Lima. Methods: Transversal study of prevalence carried out on 129 schoolchildren from the "San Gabriel" Educational Institution from the district of Villa Maria del Triunfo, in the year 2017. The salivary pH measurements were obtained using the pH-meter with the respective test-strips, and the presence of caries was evaluated in patients utilizing the CPO-D method. In addition, the sex and age characteristics were evaluated in all the patients. The statistics employed the Chi-squared test and we worked at a level of significance of p < 0.05. Results: The prevalence of dental caries found in schoolchildren between 6 and 12 years old is 85,3%. The prevalence of caries in accordance to gender was 45,7% amongst girls and 39,5% amongst boys. No statistically significant association was found between gender and the prevalence of dental caries (p = 0,935). 55% of the sample group exhibited an acidic pH, while 41,1% had a neutral pH, and 3, 9% an alkaline pH respectively. There is a statistically significant association between the salivary pH and dental caries. (p < 0,001). Conclusions: There's an existing association between salivary pH and the prevalence of dental caries. It was calculated that 95,8% of the patients with an acidic salivary pH presented dental caries. (AU)


Assuntos
Humanos , Masculino , Feminino , Saliva , Estudantes , Cárie Dentária , Concentração de Íons de Hidrogênio
9.
Braz. j. biol ; 79(4): 589-593, Nov. 2019. tab
Artigo em Inglês | LILACS (Américas) | ID: biblio-1001490

RESUMO

Abstract The objective of this study was to evaluate the ability to degrade organic matter by edaphic macrofauna (worms), carbon/nitrogen (C/N) ratio and hydrogenation potential (pH) during the vermicomposting process in different organic residues. The treatments were constituted by organic residues of animal origin (bovine, ovine and equine manure) and vegetable (herb-checkmate and coffee drag), which were conditioned in plastic pots with a capacity of 10 liters, comprising five treatments in a completely randomized experimental design, with five replications. Were inoculated 150 earthworms of the species Eisenia foetida, into each plot. After 87 days, the evaluation of the multiplication of the earthworms was carried out, through its manual count and its cocoons. At the beginning and at the end of the experiment, the samples were submitted to analysis of humidity at 60 °C, pH, volumetric density, chemical analysis of macronutrients and C/N ratio. There was a dominance of worms and cocoons in the process of vermicomposting in the residues of ovine manure and herb-checkmate. The macronutrients (P, K and Mg) and C/N ratio were higher in the vegetal residues, while for N higher values were found in ovine manure and coffee drag treatments, and for Ca higher value among treatments was observed in the coffee drag treatment at the end and the lowest value at initiation. The results obtained in this study demonstrate the importance of the edaphic macrofauna to the vermicomposting process, since it allows more information about its influence on the continuity of soil organic matter decomposition processes.


Resumo Este estudo objetivou avaliar a capacidade de degradar a matéria orgânica pela macrofauna edáfica (minhocas), a relação carbono/nitrogênio (C/N) e o potencial hidrogeniônico (pH), durante o processo da vermicompostagem em diferentes resíduos orgânicos. Os tratamentos foram constituídos por resíduos orgânicos de origem animal (esterco bovino, ovino e equino) e vegetal (resíduo de erva-mate e borra-de-café), os quais foram acondicionados em vasos plásticos com capacidade de 10 litros, compondo cinco tratamentos em delineamento experimental inteiramente casualisado, com cinco repetições. Foram inoculadas 150 minhocas da espécie Eisenia foetida, em cada recipiente. Após 87 dias, foi realizada a avaliação da multiplicação das minhocas, através da sua contagem manual e seus casulos. Os resíduos foram submetidos, ao inicio e ao final do experimento, a análises de umidade a 60 °C, pH, densidade volumétrica, análise química de macronutrientes e relação C/N. Houve uma dominância de minhocas e casulos no processo da vermicompostagem nos resíduos de esterco ovino e erva-mate. Observou-se para os macronutrientes (P, K e Mg) e para a relação C/N uma maior quantidade nos resíduos vegetais, enquanto que para N valores maiores foram encontrados nos tratamentos esterco ovino e borra-de-café, e para Ca o maior valor entre os tratamentos foi observado no tratamento com borra de café ao final e o menor valor no inicio. Os resultados obtidos neste estudo demonstram a importância da macrofauna edáfica para o processo da vermicompostagem por possibilitar maiores informações sobre sua influência na continuidade dos processos de decomposição da matéria orgânica.


Assuntos
Animais , Oligoquetos/fisiologia , Solo/química , Compostagem , Resíduos de Alimentos , Esterco/análise , Biodegradação Ambiental , Brasil , Bovinos , Carbono/análise , Carneiro Doméstico , Cavalos , Concentração de Íons de Hidrogênio , Nitrogênio/análise
10.
Electron. j. biotechnol ; 42: 6-15, Nov. 2019. ilus, graf, tab
Artigo em Inglês | LILACS (Américas) | ID: biblio-1087345

RESUMO

Background: The increasing rate of breast cancer globally requires extraordinary efforts to discover new effective sources of chemotherapy with fewer side effects. Glutaminase-free L-asparaginase is a vital chemotherapeutic agent for various tumor malignancies. Microorganisms from extreme sources, such as marine bacteria, might have high L-asparaginase productivity and efficiency with exceptional antitumor action toward breast cancer cell lines. Results: L-Asparaginase-producing bacteria, Bacillus velezensis isolated from marine sediments, were identified by 16S rRNA sequencing. L-Asparaginase production by immobilized cells was 61.04% higher than that by free cells fermentation. The significant productivity of enzyme occurred at 72 h, pH 6.5, 37°C, 100 rpm. Optimum carbon and nitrogen sources for enzyme production were glucose and NH4Cl, respectively. L-Asparaginase was free from glutaminase activity, which was crucial medically in terms of their severe side effects. The molecular weight of the purified enzyme is 39.7 KDa by SDS-PAGE analysis and was ideally active at pH 7.5 and 37°C. Notwithstanding, the highest stability of the enzyme was found at pH 8.5 and 70°C for 1 h. The enzyme kinetic parameters displayed Vmax at 41.49 µmol/mL/min and a Km of 3.6 × 10−5 M, which serve as a proof of the affinity to its substrate. The anticancer activity of the enzyme against breast adenocarcinoma cell lines demonstrated significant activity toward MDA-MB-231 cells when compared with MCF-7 cells with IC50 values of 12.6 ± 1.2 µg/mL and 17.3 ± 2.8 µg/mL, respectively. Conclusion: This study provides the first potential of glutaminase-free L-asparaginase production from the marine bacterium Bacillus velezensis as a prospect anticancer pharmaceutical agent for two different breast cancer cell lines.


Assuntos
Asparaginase/metabolismo , Bacillus/enzimologia , Neoplasias da Mama/metabolismo , Glutaminase/metabolismo , Asparaginase/biossíntese , Temperatura , Neoplasias da Mama/tratamento farmacológico , Cinética , Células Imobilizadas , Ensaios Enzimáticos , Fermentação , Células MCF-7 , Concentração de Íons de Hidrogênio
11.
Electron. j. biotechnol ; 42: 42-48, Nov. 2019. graf, tab, ilus
Artigo em Inglês | LILACS (Américas) | ID: biblio-1087459

RESUMO

Background: Foods including probiotics are considered "functional foods." As an alternative to dairy products, we investigated the behavior of Lactobacillus casei when exposed to low-pH fruit juice. Juices of fruits such as pineapple, raspberry, and orange were assessed. Free and microencapsulated forms of L. casei were compared, and the viability of the probiotic was evaluated under storage at 4°C for 28 d. Microbiological analyses were carried out to ensure a safe and healthy product for consumers who look for foods with probiotics from sources other than dairy. Results: Low pH affected L. casei survival during storage depending on the type of fruit juice. In the case of pineapple juice, some microcapsules were broken, but microcapsules recovered at the end of the storage period had 100% viability (2.3 × 107 CFU/g spheres). In the case of orange juice, more than 91% viability (5.5 × 106 CFU/g spheres) was found. In raspberry juice, viability decreased rapidly, disappearing at the end of the storage period, which was caused by the absorption of high concentrations of anthocyanin inside microcapsules more than low pH. Conclusion: Low pH affected the survival of L. casei under refrigeration; even when they were microencapsulated, acidic conditions impacted their viability. Although pH affects viability, its value is very sensitive and will depend on the type of fruit juice and its composition. Some fruit juices contain compounds used as substrates for Lactobacillus and other compounds with antimicrobial effects.


Assuntos
Viabilidade Microbiana , Sucos de Frutas e Vegetais , Lactobacillus casei/crescimento & desenvolvimento , Vibração , Temperatura Baixa , Probióticos , Alginatos/química , Armazenamento de Alimentos , Pasteurização , Concentração de Íons de Hidrogênio , Antocianinas
12.
Neumol. pediátr. (En línea) ; 14(3): 126-130, sept. 2019. tab, ilus
Artigo em Espanhol | LILACS (Américas) | ID: biblio-1087566

RESUMO

Gastroesophageal reflux is a frequent condition in the daily life of infants and older children. When reflux causes symptoms, it is called gastroesophageal reflux disease. Different extraesophageal symptoms have been frequently attributed to gastroesophageal reflux, however, new diagnostic techniques available, such as pHmetry with impedance measurement, have allowed us to evaluate and eventually dismiss such relationships. In this article we review the relationship between gastroesophageal reflux and laryngeal pathology, chronic cough, asthma and aspiration. In general terms, the empirical treatment of a presumed reflux is not recommended in asymptomatic patients, in whom its presence is not demonstrated by techniques such as pHmetry with impedance, given that therapeutic response is low and similar to placebo, with potential adverse effects.


El reflujo gastroesofágico es una condición frecuente en la vida diaria de lactantes y niños mayores. Cuando produce síntomas, se denomina enfermedad por reflujo gastroesofágico. Se ha atribuido frecuentemente diferentes síntomas extraesofágicos al reflujo, sin embargo, nuevas técnicas diagnósticas disponibles, como la pHmetría con medición de impedanciometría, han permitido evaluar y eventualmente descartar tales asociaciones. En este artículo se revisa la relación entre el reflujo gastroesofágico y patología laríngea, tos crónica, asma y aspiración. En términos generales, no se recomienda el tratamiento empírico de un supuesto reflujo en pacientes asintomáticos, en quienes tampoco esté demostrada su presencia por técnicas como la pHmetría con impedanciometría, dado que la respuesta terapéutica es baja y similar a placebo, con potenciales efectos adversos.


Assuntos
Humanos , Lactente , Criança , Doenças Respiratórias/etiologia , Refluxo Gastroesofágico/complicações , Refluxo Gastroesofágico/diagnóstico , Asma/etiologia , Refluxo Gastroesofágico/terapia , Doenças da Laringe/etiologia , Endoscopia do Sistema Digestório , Tosse/etiologia , Aspiração Respiratória/etiologia , Concentração de Íons de Hidrogênio , Manometria
13.
Electron. j. biotechnol ; 41: 60-71, sept. 2019. graf, tab, ilus
Artigo em Inglês | LILACS (Américas) | ID: biblio-1087169

RESUMO

Background: The aim of this work was to purify and characterize exo-ß-1,3-glucanase, namely, TtBgnA, from the thermophilic fungus Thielavia terrestris Co3Bag1 and to identify the purified enzyme. Results: The thermophilic biomass-degrading fungus T. terrestris Co3Bag1 displayed ß-1,3-glucanase activity when grown on 1% glucose. An exo-ß-1,3-glucanase, with an estimated molecular mass of 129 kDa, named TtBgnA, was purified from culture filtrates from T. terrestris Co3Bag1. The enzyme exhibited optimum activity at pH 6.0 and 70°C and half-lives (t1/2) of 54 and 37 min at 50 and 60°C, respectively. Substrate specificity analysis showed that laminarin was the best substrate studied for TtBgnA. When laminarin was used as the substrate, the apparent KM and Vmax values were determined to be 2.2 mg mL-1 and 10.8 U/mg, respectively. Analysis of hydrolysis products by thin-layer chromatography (TLC) revealed that TtBgnA displays an exo mode of action. Additionally, the enzyme was partially sequenced by tandem mass spectrometry (MS/MS), and the results suggested that TtBgnA from T. terrestris Co3Bag1 could be classified as a member of the GH-31 family. Conclusions: This report thus describes the purification and characterization of TtBgnA, a novel exo-ß-1,3-glucanase of the GH-31 family from the thermophilic fungus T. terrestris Co3Bag1. Based on the biochemical properties displayed by TtBgnA, the enzyme could be considered as a candidate for potential biotechnological applications.


Assuntos
Sordariales/enzimologia , Glucana 1,3-beta-Glucosidase/química , Temperatura , Estabilidade Enzimática , Celulases , Glucana 1,3-beta-Glucosidase/isolamento & purificação , Eletroforese em Gel de Poliacrilamida , Espectrometria de Massas em Tandem , Ensaios Enzimáticos , Concentração de Íons de Hidrogênio
14.
Electron. j. biotechnol ; 40: 52-57, July. 2019. graf, tab
Artigo em Inglês | LILACS (Américas) | ID: biblio-1053462

RESUMO

Background: Plastic waste is a serious problem because it is difficult to degrade, thereby leading to global environment problems. Poly(lactic acid) (PLA) is a biodegradable aliphatic polyester derived from renewable resources, and it can be degraded by various enzymes produced by microorganisms. This study focused on the scale-up and evaluated the bioprocess of PLA degradation by a crude microbial enzyme produced by Actinomadura keratinilytica strain T16-1 in a 5 L stirred tank bioreactor. Results: PLA degradation after 72 h in a 5 L bioreactor by using the enzyme of the strain T16-1 under controlled pH conditions resulted in lactic acid titers (mg/L) of 16,651 mg/L and a conversion efficiency of 89% at a controlled pH of 8.0. However, the PLA degradation process inadvertently produced lactic acid as a potential inhibitor, as shown in our experiments at various concentrations of lactic acid. Therefore, the dialysis method was performed to reduce the concentration of lactic acid. The experiment with a dialysis bag achieved PLA degradation by weight loss of 99.93%, whereas the one without dialysis achieved a degradation of less than approximately 14.75%. Therefore, the dialysis method was applied to degrade a commercial PLA material (tray) with a conversion efficiency of 32%, which was 6-fold more than that without dialysis. Conclusions: This is the first report demonstrating the scale-up of PLA degradation in a 5 L bioreactor and evaluating a potential method for enhancing PLA degradation efficiency.


Assuntos
Poliésteres/metabolismo , Actinomycetales/enzimologia , Enzimas/metabolismo , Polímeros/metabolismo , Biodegradação Ambiental , Ácido Láctico/análise , Reatores Biológicos , Concentração de Íons de Hidrogênio
15.
J. Health Biol. Sci. (Online) ; 7(2): 121-125, abr.-jun. 2019.
Artigo em Inglês | LILACS (Américas) | ID: biblio-1005693

RESUMO

Objective: to evaluate antimicrobial action, pH, and tissue dissolution capacity of 2.5% sodium hypochlorite (NaOCl) gel and solution. Methods: The 2.5% NaOCl gel was produced from a colloidal base. The test groups included 2.5% NaOCl gel and solution and the control groups included gel base and distilled water. The antimicrobial activity was evaluated by the broth dilution technique against Enterococcus faecalis (ATCC 29212) at 15 and 30 seconds and at 1, 5, and 10 minutes. To evaluate tissue dissolution capacity, 30 pulp fragments of bovine incisors were weighed, 10 for each test group and 5 for each control group before and after exposure to the chemical auxiliaries. The final mass percentage of each fragment was calculated. The pH of the substances was measured in triplicate through a digital pH meter. Results: pH levels of 13.08 and 9.75 were observed for 2.5% NaOCl solution and gel, respectively. The antimicrobial action of 2.5% NaOCl was the same for both solution and gel, for all tested times. The 2.5% NaOCl solution group showed higher tissue dissolution capacity (Kruskal-Wallis and Student-Newman-Keuls tests P<0.0001). Conclusions: The type of medium, either solution or gel, containing 2.5% NaOCl did not influence the antimicrobial action at any of the tested times. However, 2.5% NaOCl gel did not present tissue dissolution capacity


Objetivo: avaliar a ação antimicrobiana, pH e capacidade de dissolução tecidual promovida por hipoclorito de sódio (NaOCl) 2,5%, nas formas líquida e gel. Métodos: O gel de NaOCl 2,5% foi produzido a partir de base coloidal. Os grupos testes foram NaOCl 2,5% gel e solução e os grupos controle incluíram a base gel e água destilada. A ação antimicrobiana foi avaliada por meio de método de diluição em caldo, frente a Enterococcus faecalis (ATCC 29212) após 15 e 30 segundos, e também a 1, 5 e 10 minutos. Para o teste de diluição tecidual, 35 fragmentos de polpa bovina (sendo 10 para cada grupo teste e 5 para o grupo controle) foram pesadas antes e após a exposição aos auxiliares químicos. O percentual de massa final de cada fragmento foi calculada. O pH dos auxiliares químicos foi medido em pHmetro digital, em triplicata. Resultados: Valores de pH iguais a 13,08 e 9,75 foram observados para solução e para o gel de NaOCl, respectivamente. A ação antimicrobiana do NaOCl foi a mesma para o gel e a solução, em todos os períodos testados. Maior capacidade de dissolução tecidual foi obtida no grupo onde se utilizou a solução de NaOCl 2,5% (Testes de Kruskal-Wallis e Student-Newman-Keuls, P<0,0001). Conclusões: A apresentação na forma de gel ou de líquido do NaOCl 2,5% não modificou a ação antimicrobiana em qualquer um dos períodos testados. Porém, o gel de NaOCl 2,5% não demonstrou capacidade de dissolução tecidual.


Assuntos
Testes de Sensibilidade Microbiana , Polpa Dentária , Concentração de Íons de Hidrogênio , Hipoclorito de Sódio , Enterococcus faecalis , Dissolução
16.
Rev. argent. microbiol ; 51(1): 56-65, mar. 2019. ilus, graf, tab
Artigo em Inglês | LILACS (Américas) | ID: biblio-1003281

RESUMO

Thermoacidophiles can exist in a state of dormancy both in moderate temperatures and even in cold conditions in heap leaching. Sulphide mineral ores such as chalcopyrite produce sulfuric acid when exposed to the air and water. The produced sulfuric acid leads to the decrease of pH and exothermic reactions in heap leaching causing the temperature to increase up to 55 °C and the activation of thermoacidophilic microorganisms. The aim of the present study was to isolate indigenous extreme thermoacidophilic microorganisms at ambient temperature from Sarcheshmeh Copper Complex, to adapt them to the high pulp density of a chalcopyrite concentrate, and to determine their efficiency in chalcopyrite bioleaching in order to recover copper. In this study samples were collected at ambient temperature from Sarcheshmeh Copper Complex in Iran. Mixed samples were inoculated into the culture medium for enrichment of the microorganisms. Pure cultures from these enrichments were obtained by subculture of liquid culture to solid media. Morphological observation was performed under the scanning electron microscope. Isolates were adapted to 30% (w/v) pulp density. For the bioleaching test, the experiments were designed with DX7 software. Bioleaching experiments were carried out in Erlenmeyer flasks and a stirred tank reactor. The highest copper recovery in Erlenmeyer flasks was 39.46% with pulp 15%, inoculums 20%, size particle 90 pm and 160 rpm. The lowest recovery was 3.81% with pulp 20%, inoculums 20%, size particle 40 pm and 140 rpm after 28 days. In the reactor, copper recovery was 32.38%. Bioleaching residues were analyzed by the X-ray diffraction (XRD) method. The results showed no jarosite (KFe3(SO4)2(OH)6) had formed in the bioleaching experiments. It seems that the antagonistic reactions among various species and a great number of planktonic cells in Erlenmeyer flasks and the stirred tank reactor are the reasons for the low recovery of copper in our study.


Los microorganismos termoacidófilos pueden estar en estado latente tanto a temperatura moderada como baja, en lixiviación en pilas. Los minerales sulfurosos, como la calcopirita, producen ácido sulfúrico cuando se exponen al aire y al agua. El ácido sulfúrico producido conduce a la disminución del pH y a reacciones exotérmicas durante la lixiviación en pilas, lo que hace que la temperatura aumente hasta 55 °C y se activen los microorganismos termoacidófilos. El objetivo del presente estudio fue aislar del complejo de cobre Sarchesh-meh (Irán) microorganismos termoacidófilos extremos que proliferan a temperatura ambiente e investigar su adaptación a la alta densidad de pulpa del concentrado de calcopirita, así como su eficiencia para biolixiviarese mineral, con el objeto de recuperar el cobre. Se recogieron muestras a temperatura ambiente del citado complejo, y luego muestras mixtas se inocularon en un medio de cultivo de enriquecimiento. A partir de estos enriquecimientos, mediante el subcultivo del cultivo líquido a medio sólido, se obtuvieron cultivos puros. La observación morfológica se realizó bajo microscopio electrónico de barrido. Los aislados estaban adaptados al 30% p/v de densidad de pulpa. Para la prueba de biolixiviación, los experimentos fueron diseñados con el software DX7. Los experimentos de biolixiviación se llevaron a cabo en Erlenmeyers y en un reactor tanque con agitación. La mayor recuperación de cobre en los Erlenmeyers fue del 39,46% y se obtuvo con la pulpa al 15%, un inóculo del 20%, un tamaño de partícula de 90 µm y una agitación de 160 rpm. La menor recuperación fue del 3,81% y se obtuvo con la pulpa al 20%, un inóculo del 20%, un tamaño de partícula de 40 µm y una agitación de 140 rpm, después 28 días. En el reactor, la recuperación del cobre fue del 32,38%. El análisis de difracción de rayos X (XRD) no mostró que se formara jarosita (KFe3-#91;SO4-#93;2-#91;OH-#93;6) en los experimentos de biolixiviación. Dicha técnica sirve para determinar la estructura cristalina de una sustancia desconocida. Al parecer, las reacciones antagónicas entre las diversas especies y el mayor número de células planctónicas en los Erlenmeyers y en el reactor fueron las causas de la baja recuperación de cobre observada en este estudio.


Assuntos
Percolação/análise , Reações Químicas/análise , Cobre/economia , Causalidade , Adaptação , Concentração de Íons de Hidrogênio
17.
Pesqui. bras. odontopediatria clín. integr ; 19(1): 4107, 01 Fevereiro 2019. tab
Artigo em Inglês | LILACS (Américas), BBO | ID: biblio-997911

RESUMO

Objective: To evaluate the influence of gustatory stimuli on the buffering capacity of saliva. Material and Methods: The buccal ph of 18 male volunteers aged 18-35 years was measured after a mouthwash with 20 ml of water as a control, and in individual disposable cups they collected the saliva for two minutes. Then, each of chewed bubble gum with sugar for two minutes, discarding the gum and made new collection of saliva, for two minutes in other disposable cups individualized. After collection, each volunteer was again subject to regular brushing with toothpaste and waited another ten minutes. The same procedure was repeated with all other substances. Salivary buffer capacity was determined by Ericsson technique. Data were submitted to analysis of variance and the means were compared by the Scott-Knott grouping test and Mann-Whitney test at 5% probability. Estimates of Pearson correlations were calculated in order to determine possible associations between the variables. Results: It was not found statistically significant differences between the initial pH variation and after eating food (p>0.05), or between gustatory stimulation and variation of salivary buffer capacity (p>0.05). Conclusion: There is no influence of gustatory stimulus aroma and flavor on the variation of salivary buffer capacity.


Assuntos
Humanos , Masculino , Adolescente , Adulto , Saliva/metabolismo , Papilas Gustativas , Dieta , Percepção Gustatória , Concentração de Íons de Hidrogênio , Salivação , Brasil , Tampões (Química) , Análise de Variância , Estatísticas não Paramétricas
18.
Braz. j. biol ; 79(1): 104-110, Jan.-Mar 2019. tab
Artigo em Inglês | LILACS (Américas) | ID: biblio-984011

RESUMO

Abstract Fruit flies (Diptera: Tephritidae) are considered the main fruit pests worldwide. In Brazil, two species are predominant: the South American fruit fly, Anastrepha fraterculus and the Mediterranean fruit fly, Ceratitis capitata. In this study, we evaluated the effect of artificial diets with variable pH in their larval development and adult performance. The experiments were carried out in the laboratory at 25 ± 2 °C, 70 ± 10% RH and 12:12h (L:D) photoperiod. Semisolid diets with pH values of 6.0, 5.0, 4.0, 3.0, 2.0, 1.5, and 1.0, adjusted by adding hydrochloric acid were tested. Results indicated that the diet with pH 6.0 did not support larval development of both species of fruit fly. Diets with greater acidic pH values did not allow egg, larvae or pupae development and adult reproduction of A. fraterculus. For C. capitata , the pH of artificial diet exerts greater influence compared to A. fraterculus on the duration and viability of the larval stage, number of pupae, sex ratio and longevity of males.


Resumo As moscas-das-frutas (Diptera: Tephritidae) são consideradas as principais pragas da fruticultura mundial. No Brasil, duas espécies são predomindantes: a mosca-das-frutas Sul-americana, Anastrepha fraterculus e a mosca-do-Mediterrâneo, Ceratitis capitata. Neste estudo avaliamos o efeito de dietas artificiais com pH variável no seu desenvolvimento larval e performance de adultos. Os experimentos foram realizados em laboratório a 25 ± 2 °C, 70 ± 10% UR e fotoperíodo de 12:12 horas. Foram testadas dietas semi-sólidas com valores de pH de 6,0; 5,0; 4,0; 3,0; 2,0; 1,5 e 1,0, ajustados pela adição de ácido clorídrico. Os resultados indicaram que a dieta com pH 6,0 não suportou o desenvolvimento larval de ambas as espécies de mosca-das-frutas. As dietas com pH ácido não permitiram o desenvolvimento de ovos, larvas ou pupas e a reprodução de adultos de A. fraterculus. Para C. capitata o pH da dieta artificial exerceu maior influência do que para A. fraterculus nos parâmetros de duração e viabilidade do estágio larval, número de pupas, razão sexual e longevidade de machos.


Assuntos
Animais , Masculino , Feminino , Controle de Insetos/métodos , Tephritidae/fisiologia , Ração Animal/análise , Óvulo/crescimento & desenvolvimento , Pupa/crescimento & desenvolvimento , Especificidade da Espécie , Tephritidae/crescimento & desenvolvimento , Ceratitis capitata/crescimento & desenvolvimento , Ceratitis capitata/fisiologia , Dieta , Concentração de Íons de Hidrogênio , Larva/crescimento & desenvolvimento
19.
Chinese Journal of Biotechnology ; (12): 415-424, 2019.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-771365

RESUMO

Acid protease, an important aspartic protease, has been widely used in food, pharmaceutical and tanning industries. To promote the research and application of acid protease, an acid protease gene (pepA) from Aspergillus oryzae was obtained from fermented soy based on metagenome sequencing, and then cloned and transformed into Pichia pastoris GS115 for heterologous expression. The characteristic of recombinant PepA was also investigated. The activity of acid protease in the culture supernatant of P. pastoris was 50.62 U/mL. The molecular mass of PepA was about 50 kDa, and almost no other proteins in the supernatant were observed, as shown by SDS-PAGE. The optimum pH and temperature of PepA were determined as pH 4.5 and 50 ℃. Mn²⁺ and Cu²⁺ enhanced the activity of PepA, whereas Fe³⁺, Fe²⁺ and Ca² had inhibitory effects on its activity. The above findings can provide guidance for heterologous expression and industrial application of acid protease from Aspergillus oryzae.


Assuntos
Aspergillus oryzae , Clonagem Molecular , Endopeptidases , Concentração de Íons de Hidrogênio , Pichia , Proteínas Recombinantes , Temperatura
20.
Chinese Journal of Biotechnology ; (12): 513-521, 2019.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-771356

RESUMO

To explore the immobilization of target proteins for screening libraries of ligand mixtures, magnetic submicron particles (MSP) functionalized with Ni²⁺-NTA and carboxyl were compared for the immobilization of Mycobacterium tuberculosis dihydrofolate reductase (MtDHFR). MtDHFR fused with 6×His was expressed, purified and characterized for kinetics. MtDHFR was immobilized on Ni²⁺-NTA-functionalized MSP directly and carboxyl-functionalized MSP upon activation. The immobilization capacity, residual activity, thermostability and affinities for putative inhibitors were characterized. MtDHFR immobilized on Ni²⁺-NTA-functionalized MSP retained about 32% activity of the free one with the immobilization capacity of (93±12) mg/g of MSP (n=3). Ni²⁺ and EDTA synergistically inhibited MtDHFR activity, while Fe³⁺ had no obvious interference. MtDHFR immobilized on carboxyl-functionalized MSP retained (87±4)% activity of the free one with the immobilization capacity of (8.6±0.6) mg/g MSP (n=3). In 100 mmol/L HEPES (pH 7.0) containing 50 mmol/L KCl, there was no significant loss of the activities of the free and immobilized MtDHFR after storage at 0 °C for 16 h, but nearly 60% and 35% loss of their activities after storage at 25 °C for 16 h, respectively. The inhibition effects of methotrexate on the immobilized and free MtDHFR were consistent (P>0.05). The immobilization of MtDHFR on carboxyl-functionalized MSP was thus favorable for higher retained activity and better thermostability, with promise for rapid screening of its ligand mixtures.


Assuntos
Estabilidade Enzimática , Enzimas Imobilizadas , Concentração de Íons de Hidrogênio , Cinética , Ligantes , Nanopartículas de Magnetita , Mycobacterium tuberculosis , Temperatura , Tetra-Hidrofolato Desidrogenase
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA