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1.
Arq. Inst. Biol ; 86: e1212018, 2019. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1024562

RESUMO

In this study, we investigated the contamination of refrigerated raw milk produced in the western region of Paraná, southern Brazil, with psychrotrophic microorganisms, aiming to assay the proteolytic activity of the isolates and to identify Pseudomonas fluorescens, the main proteolytic species associated with the spoilage of milk products. Raw milk samples from 50 dairy farms were submitted to the counting of psychrotrophic microorganisms, being the microbiota characterized by its mesophilic behavior and proteolytic capacity, besides molecular identification of P. fluorescens. Of the samples evaluated, 94% had psychrotrophic counts ranging from 3 to 7.1 log CFU mL-1, and 48.5% of these showed mesophilic behavior. Of the isolates, 48.0% had proteolytic activity in at least one evaluated temperature (21 and 30°C), and 39.3% had proteolytic activity in both temperatures. Among the 61 isolates submitted to molecular identification by polymerase chain reaction (PCR), 86.8% contained the expression of the 16S gene characteristic for P. fluorescens. In this study, we demonstrated that P. fluorescens is the most prevalent psychrotrophic bacteria species in raw refrigerated milk and their proteolytic ability poses high risks to the dairy industry.(AU)


No presente estudo, investigamos a contaminação do leite cru refrigerado produzido na região oeste do Paraná, sul do Brasil, com micro-organismos psicrotróficos, visando testar a atividade proteolítica dos isolados e identificar Pseudomonas fluorescens, a principal espécie proteolítica associada à deterioração de produtos lácteos. Amostras de leite cru de 50 fazendas leiteiras foram submetidas à contagem de micro-organismos psicrotróficos, caracterizando-se a microbiota por seu comportamento mesofílico e sua capacidade proteolítica, além de identificação molecular de P. fluorescens. Entre as amostras avaliadas, 94% apresentaram contagem psicrotrófica variando de 3 a 7,1 log UFC mL-1 e 48,5% destas apresentaram comportamento mesofílico. Entre os isolados, 48,0% apresentaram atividade proteolítica em pelo menos uma das temperaturas testadas (21 e 30°C) e 39,3% apresentaram atividade proteolítica em ambas as temperaturas. Entre os 61 isolados sub-metidos à identificação molecular por reação em cadeia da polimerase (PCR), 86,8% continham expressão do gene 16S característico de P. fluorescens. Neste estudo, demonstramos que P. fluorescens é a espécie de bactérias psicrotróficas mais prevalente em leite refrigerado cru e sua capacidade proteolítica promove elevados riscos de deterioração para a indústria de laticínios.(AU)


Assuntos
Pseudomonas fluorescens , Leite , Proteólise , Bactérias , Contaminação de Alimentos , Reação em Cadeia da Polimerase , Alimentos Resfriados
2.
Arq. bras. med. vet. zootec. (Online) ; 70(1): 247-253, Jan.-Feb. 2018. tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-888089

RESUMO

Este trabalho se propôs a desenvolver um modelo preditivo para identificação de perda de estabilidade e de sedimentação em leite UAT por determinação da atividade enzimática de aminopeptidase no leite por espectrofotometria. Foram analisadas amostras de leite cru, pasteurizado e UAT após envase durante seis meses, na região Sul do Brasil. Acidez, crioscopia, gordura, extrato seco total, extrato seco desengordurado e densidade foram analisados nos leites cru e pasteurizado. Amostras de leite cru foram ainda submetidas à análise de contagem de psicrotróficos e à atividade de aminopeptidase, e amostras de leite UAT estocadas foram analisadas quanto ao grau de proteólise mediante análises sensoriais e atividade de aminopeptidase. Alterações sensoriais foram observadas em tempos de estocagem menores para amostras originadas de leite cru com contagem de psicrotróficos acima de 107 UFC mL-1. Não houve correlação entre a atividade de aminopeptidase e proteólise e também não foi observada correlação significativa entre os parâmetros físico-químicos e a ocorrência de proteólise no leite estocado. O modelo estudado não foi apto para predizer perda de estabilidade e ocorrência de proteólise no leite UAT.(AU)


The aim of this work was to develop a predictive model for identifying loss of stability and sedimentation in UHT milk by determining the enzymatic activity of aminopeptidasis in milk by spectrophotometry. Samples of raw milk, pasteurized and UHT after filling for 6 months in Southern Brazil were analyzed. Acidity, freezing point, fat, total solids, nonfat solids and density were analyzed in raw and pasteurized milk. Raw milk samples were also subjected to psychrotrophic count analysis and aminopeptidasis activity and UAT samples of stored milk were analyzed for degree of proteolysis through sensory analysis and aminopeptidasis activity. Sensory changes were observed in smaller storage time for samples of raw milk originated with psychrotrophic count above 107 CFU ml-1. There was no correlation between aminopeptidasis activity and proteolysis and there was also no significant correlation between physicochemical parameters and the occurrence of proteolysis in stored milk. The model was unable to predict loss of stability and occurrence of proteolysis in UHT milk.(AU)


Assuntos
Animais , Feminino , Bovinos , Aminopeptidases/análise , Leite/enzimologia , Proteólise , Bovinos , Espectrofotometria
3.
Electron. j. biotechnol ; 29: 7-12, sept. 2017. ilus, graf, tab
Artigo em Inglês | LILACS | ID: biblio-1016095

RESUMO

Background: DegP is a serine protease that specifically cleaves and refolds unfolding proteins in the periplasmic space of the cells. To date, there is no information regarding DegP from halophilic bacteria. Chromohalobacter salexigens BKL5 is a moderately halophilic bacterium that has the ability to grow in a media containing more than 15% salt. Therefore, the objectives of this work were to clone and overexpress DegP-encoding gene from C. salexigens BKL5 and characterize its biochemical properties. Results: DegP-encoding gene was overexpressed in Escherichia coli BL21(DE3) CodonPlus in an active form. SDS-PAGE analysis showed that the molecular weight of the recombinant DegP was 45 kDa. Size-exclusion chromatography analysis suggested that recombinant DegP was present in two multimeric states, hexameric and dodecameric, with molecular weights of 297.9 and 579.12 kDa, respectively. Both conformations were enzymatically active when casein was used as substrate for enzymatic assay. Circular dichroism analysis showed that recombinant DegP was composed of 0.21­0.29 helical content, which was comparable to the helical content in the crystal structure of E. coli DegP. The basic/acidic residue ratio of recombinant DegP was 0.56, which was slightly higher than that of DegP from extreme halophiles (average, 0.45) but significantly lower than that of DegP from nonhalophiles (average, 0.94). Conclusions: Recombinant DegP from C. salexigens BKL5 showed proteolytic activity when ß-casein was used as a substrate. In silico analysis indicated that recombinant DegP had characteristics similar to those of halophilic proteins depending on its amino acid composition.


Assuntos
Serina Endopeptidases/genética , Proteínas Periplásmicas/genética , Chromohalobacter/enzimologia , Proteólise , Proteínas de Choque Térmico/genética , Proteínas Recombinantes , Serina Endopeptidases/metabolismo , Caseínas , Cromatografia em Gel , Dicroísmo Circular , Clonagem Molecular , Proteínas Periplásmicas/metabolismo , Eletroforese em Gel de Poliacrilamida , Escherichia coli , Salinidade , Chromohalobacter/genética , Proteínas de Choque Térmico/metabolismo , Peso Molecular
4.
Braz. j. microbiol ; 48(1): 13-24, Jan.-Mar. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-839339

RESUMO

Abstract Specific proteases capable of degrading native triple helical or denatured collagen have been required for many years and have a large spectrum of applications. There are few complete reports that fully uncover production, characterization and purification of fungi collagenases. In this review, authors searched through four scientific on line data bases using the following keywords (collagenolytic OR collagenase) AND (fungi OR fungus OR fungal) AND (production OR synthesis OR synthesize) AND (characterization). Scientific criteria were adopted in this review to classify found articles by score (from 0 to 10). After exclusion criteria, 21 articles were selected. None obtained the maximum of 10 points defined by the methodology, which indicates a deficiency in studies dealing simultaneously with production, characterization and purification of collagenase by fungi. Among microorganisms studied the non-pathogenic fungi Penicillium aurantiogriseum and Rhizoctonia solani stood out in volumetric and specific collagenase activity. The only article found that made sequencing of a true collagenase showed 100% homology with several metalloproteinases fungi. A clear gap in literature about collagenase production by fungi was verified, which prevents further development in the area and increases the need for further studies, particularly full characterization of fungal collagenases with high specificity to collagen.


Assuntos
Colágeno/metabolismo , Colagenases/metabolismo , Fungos/metabolismo , Especificidade por Substrato , Colágeno/química , Colagenases/isolamento & purificação , Colagenases/biossíntese , Colagenases/química , Meios de Cultura , Ativação Enzimática , Proteólise , Fungos/classificação
5.
Braz. j. med. biol. res ; 50(12): e6733, 2017. graf
Artigo em Inglês | LILACS | ID: biblio-888967

RESUMO

Myostatin is a novel negative regulator of skeletal muscle mass. Myostatin expression is also found in heart in a much less extent, but it can be upregulated in pathological conditions, such as heart failure. Myostatin may be involved in inhibiting protein synthesis and/or increasing protein degradation in skeletal and cardiac muscles. Herein, we used cell cultures and isolated muscles from rats to determine protein degradation and synthesis. Muscles incubated with myostatin exhibited an increase in proteolysis with an increase of Atrogin-1, MuRF1 and LC3 genes. Extensor digitorum longus muscles and C2C12 myotubes exhibited a reduction in protein turnover. Cardiomyocytes showed an increase in proteolysis by activating autophagy and the ubiquitin proteasome system, and a decrease in protein synthesis by decreasing P70S6K. The effect of myostatin on protein metabolism is related to fiber type composition, which may be associated to the extent of atrophy mediated effect of myostatin on muscle.


Assuntos
Animais , Masculino , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miostatina/farmacologia , Proteínas Musculares/efeitos dos fármacos , Proteínas Musculares/metabolismo , Fosforilação/efeitos dos fármacos , Fosforilação/fisiologia , Fatores de Tempo , Tirosina/efeitos dos fármacos , Tirosina/metabolismo , Expressão Gênica , Células Cultivadas , Western Blotting , Reprodutibilidade dos Testes , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Proteólise/efeitos dos fármacos
6.
Einstein (Säo Paulo) ; 13(4): 510-517, Oct.-Dec. 2015. tab, graf
Artigo em Português | LILACS | ID: lil-770491

RESUMO

ABSTRACT Objective To determine the presence of glycosaminoglycans in the extracellular matrix of connective tissue from neoplastic and non-neoplastic colorectal tissues, since it has a central role in tumor development and progression. Methods Tissue samples from neoplastic and non-neoplastic colorectal tissues were obtained from 64 operated patients who had colorectal carcinoma with no distant metastases. Expressions of heparan sulphate, chondroitin sulphate, dermatan sulphate and their fragments were analyzed by electrospray ionization mass spectrometry, with the technique for extraction and quantification of glycosaminoglycans after proteolysis and electrophoresis. The statistical analysis included mean, standard deviation, and Student’st test. Results The glycosaminoglycans extracted from colorectal tissue showed three electrophoretic bands in agarose gel. Electrospray ionization mass spectrometry showed characteristic disaccharide fragments from glycosaminoglycans, indicating their structural characterization in the tissues analyzed. Some peaks in the electrospray ionization mass spectrometry were not characterized as fragments of sugars, indicating the presence of fragments of the protein structure of proteoglycans generated during the glycosaminoglycan purification. The average amount of chondroitin and dermatan increased in the neoplastic tissue compared to normal tissue (p=0.01). On the other hand, the average amount of heparan decreased in the neoplastic tissue compared to normal tissue (p= 0.03). Conclusion The method allowed the determination of the glycosaminoglycans structural profile in colorectal tissue from neoplastic and non-neoplastic colorectal tissue. Neoplastic tissues showed greater amounts of chondroitin sulphate and dermatan sulphate compared to non-neoplastic tissues, while heparan sulphate was decreased in neoplastic tissues.


RESUMO Objetivo Determinar a presença de glicosaminoglicanos na matriz extracelular do tecido conjuntivo colorretal neoplásico e não neoplásico, tendo em vista seu papel central no desenvolvimento e na progressão dos tumores. Métodos Amostras de tecidos colorretais neoplásicos e não neoplásicos foram obtidas de 64 pacientes operados com carcinoma colorretal sem metástases a distância. As expressões de heparan sulfato, sulfato de condroitina e sulfato de dermatan e seus fragmentos foram analisadas por espectrometria de massa por ionização por electrospray, com técnica de extração e quantificação de glicosaminoglicanos após proteólise e eletroforese. Para análise estatística, utilizaram-se média, desvio padrão e teste t de Student. Resultados Em gel de agarose, os glicosaminoglicanos extraídos de tecido colorretal mostraram três bandas eletroforéticas. A espectrometria de massa por ionização por electrospray mostrou fragmentos de dissacarídeos característicos de glicosaminoglicanos e indicou sua característica estrutural. Alguns picos na espectrometria de massa por ionização por electrospray não foram caracterizados como fragmentos de açúcares, sugerindo a presença de fragmentos de proteínas estruturais dos proteoglicanos, formadas durante a purificação dos glicosaminoglicanos. A quantidade média de condroitina e dermatan aumentou no tecido neoplástico em relação ao tecido normal (p=0,01). Por outro lado, a quantidade média de heparan foi menor no tecido neoplásico em relação ao tecido normal (p=0,03). Conclusão O método empregado permitiu determinar o perfil estrutural dos glicosaminoglicanos nas amostras. Tecidos neoplásicos apresentaram maiores quantidades de sulfato de condroitina e sulfato de dermatan em comparação com os não neoplásicos, enquanto o sulfato de heparan foi encontrado em menores quantidades nos tecidos neoplásicos.


Assuntos
Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma/química , Neoplasias Colorretais/química , Matriz Extracelular/química , Glicômica/métodos , Glicosaminoglicanos/análise , Carcinoma/patologia , Sulfatos de Condroitina/análise , Neoplasias Colorretais/patologia , Tecido Conjuntivo/química , Progressão da Doença , Dermatan Sulfato/análise , Eletroforese em Gel de Poliacrilamida , Heparitina Sulfato/análise , Membrana Mucosa/metabolismo , Proteólise , Espectrometria de Massas por Ionização por Electrospray
7.
Arch. endocrinol. metab. (Online) ; 59(5): 400-406, Oct. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-764111

RESUMO

Objective To evaluate the effect of six-week anaerobic training on the mRNA expression of genes related to proteolysis Ubb (Ubiquitin), E2-14kDa, Trim63 (MuRF1 protein) and Nfkb1 in the skeletal muscle of diabetic rats.Materials and methods Four groups were established: DE (DiabetesExercised), DS (Diabetes Sedentary), CE (Control Exercised) and CS (Control Sedentary). The training consisted of 3 sets of 12 jumps in the liquid mean with load equivalent to 50% of BW for 6 weeks. Euthanasia occurred under ip anesthesia, and blood, adipose tissue and skeletal muscles were collected. Gene expression was quantified by RT–PCR in the gastrocnemius muscle. ANOVA one-way was used for comparison among groups, with post-hoc (Tukey) when necessary, considering p < 0.05.Results We observed reduction in the body weight and adipose tissue in the diabetic groups. The muscle mass was reduced in DS, which could be reversed by training (DE). Although DS and DE have presented similar body weight, the training protocol in DE promoted reduction in the adipose tissue, and increase of muscle mass. Anaerobic training was efficient to reduce glycaemia only in the diabetic animals until 6 hours after the end of training. The Trim63 gene expression was increased in DS; decreased Ubb gene level was observed in trained rats (CE and DE) compared to sedentary (CS and DS), and DE presented the lowest level of E2-14kDa gene expression.Conclusion Six-week anaerobic training promoted muscle mass gain, improved glycemic control, and exerted inhibitory effect on the proteolysis of gastrocnemius muscle of diabetic rats.


Assuntos
Animais , Masculino , Diabetes Mellitus/metabolismo , Músculo Esquelético/fisiologia , Proteólise , Condicionamento Físico Animal/fisiologia , Anaerobiose , Tecido Adiposo/anatomia & histologia , Glicemia/análise , Peso Corporal/fisiologia , Expressão Gênica , Modelos Animais , Músculo Esquelético/anatomia & histologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Distribuição Aleatória , Ratos Wistar , RNA Mensageiro/metabolismo , Ubiquitina/genética , Ubiquitina/metabolismo
8.
Pesqui. vet. bras ; 35(6): 518-524, June 2015. tab
Artigo em Português | LILACS | ID: lil-766189

RESUMO

A mastite é a principal afecção do gado destinado à produção leiteira, que impacta significativamente a cadeia produtiva do leite, com reflexos ainda para a saúde pública. Estudou-se aspectos relacionados à etiologia, celularidade e de contagem bacteriana em 10 propriedades leiteiras, localizadas no Estado de São Paulo. Foram examinadas 1148 vacas em lactação, totalizando 4584 glândulas mamárias. Foram considerados os casos, em que houve isolamento de estafilococos coagulase positiva (SCP) e estafilococos coagulase negativa (SCN). Os resultados revelaram microbiota com vários patógenos e diferentes espécies de SCN (128 casos) e SCP (45), Staphylococcus aureus(90), Streptococcus agalactiae(70), Streptococcus dysgalactiae (69), Streptococcus uberis(29), Corynebacteriumspp. (230), Klebsiella pneumoniae(28), Klebsiella oxytoca(2), Escherichia coli(15), Enterobactersp. (3). Os resultados de contagem de células somáticas (CCS) relacionados aos SCP e SCN não mostraram diferenças entre as propriedades avaliadas, entretanto com diferenças significantes ao se avaliar a CCS entre os dois grupos de estafilococos, como pode ser evidenciado ao comparar SCN Discreto e SCP exuberante (P<0,01), SCP Discreto e SCP exuberante (P<0,001) e SCN moderado e SCP exuberante (P<0,01). A avaliação da CCS relacionada à intensidade da infecção, considerando-se como crescimento discreto o isolamento de até nove colônias, moderado de dez a 29 colônias e exuberante, com 30 ou mais colônias, revelou para ambos os grupos de estafilococos que quanto maior o número de unidades formadoras de colônias (UFC), a CCS é mais elevada, sendo sempre maior nos casos de SCP. Conclui-se que quando há maior número de UFC, há concomitantemente maior CCS/mL de leite, no caso dos SCP e SCN...


Mastitis is the main affection of cattle intended for dairy production, which significantly impacts the milk production chain, with consequences yet to public health. It was studied aspects related to etiology, cellularity and bacterial count in 10 dairy farms, in the State of São Paulo. There were examined 1148 milking cows, totaling 4584 mammary glands. Cases in which there was isolation coagulase positive staphylococci (CPS) and coagulase-negative staphylococci (CNS) were considered. The results showed microbiota with various different pathogens and CNS (128 cases) and CPS (45), Staphylococcus aureus (90), Streptococcus agalactiae (70), Streptococcus dysgalactiae (69), Streptococcus uberis (29), Corynebacterium spp . (230), Klebsiella pneumoniae (28), Klebsiella oxytoca (2), Escherichia coli (15), Enterobacter spp. (3). The somatic cell count (SCC) related to CPS and CNS showed no differences among the evaluated properties, although with significant differences when evaluating the SCC between both groups of staphylococci, as evidenced by comparing discreet CNS and exuberant CPS (P <0.01), discreet CPS and exuberant CPS (P <0.001) and moderate SCN and exuberant SCP (P <0.01). The evaluation of SCC was related to the intensity of infection, considering how slight growth isolation of up to nine colonies, moderate ten to 29 colonies and lush, with 30 or more colonies, revealed for both groups of staphylococci that the higher the number of colony forming units (CFU), SCC is higher being larger in cases of CPS. The results indicate that the importance of both CPS and CNS when considering the high occurrence of the evaluated properties and the fact that it raises the SCC, which compromises the quality of milk. We conclude that when there is a larger number of CFU, is concomitantly higher SCC/ml of milk, in the case of CPS and CNS...


Assuntos
Animais , Feminino , Bovinos , Substitutos do Leite Humano , Mastite Bovina/epidemiologia , Mastite Bovina/prevenção & controle , Controle de Qualidade , Staphylococcus , Criação de Animais Domésticos/métodos , Prevenção de Doenças , Proteólise , Células-Tronco
9.
Int. arch. otorhinolaryngol. (Impr.) ; 19(2): 112-115, Apr-Jun/2015. tab
Artigo em Inglês | LILACS | ID: lil-747142

RESUMO

Introduction Parotid gland incidentalomas (PGIs) are unexpected hypermetabolic foci in the parotid region that can be found when scanning with whole-body positron emission/computed tomography (PET/CT). These deposits are most commonly due to benign lesions such as Warthin tumor. Objective The aim of this study was to determine the prevalence of PGIs identified in PET/CT scans and to assess the role of smoking in their etiology. Methods We retrospectively reviewed all PET/CT scans performed at our center in search of PGIs and identified smoking status and standardized uptake value (SUVmax) in each case. We also analyzed the database of parotidectomies performed in our department in the previous 10 years and focused on the pathologic diagnosis and the presence or absence of smoking in each case. Results Sixteen cases of PGIs were found in 4,250 PET/CT scans, accounting for 0.4% . The average SUVmax was 6.5 (range 2.8 to 16). Cytology was performed in five patients; it was benign in four cases and inconclusive in one case. Thirteen patients had a history of smoking. Of the parotidectomies performed in our center with a diagnosis of Warthin tumor, we identified a history of smoking in 93.8% of those patients. Conclusions The prevalence of PGIs on PET/CT was similar to that reported by other authors. Warthin tumor is frequently diagnosed among PGIs on PET/CT, and it has a strong relationship with smoking. We suggest that a diagnosis other than Warthin tumor should be considered for PGIs in nonsmokers. .


Assuntos
Humanos , Proteínas ADAM/metabolismo , Proteólise , Fator de von Willebrand/química , Fator de von Willebrand/metabolismo , Sítios de Ligação , Cálcio/metabolismo , Dissulfetos/química , Dissulfetos/metabolismo , Ligação de Hidrogênio , Modelos Moleculares , Mutagênese Sítio-Dirigida , Ligação Proteica , Estabilidade Proteica , Estrutura Terciária de Proteína , Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismo , Fator de von Willebrand/genética
10.
Braz. j. microbiol ; 46(1): 251-260, 05/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-748253

RESUMO

An Aspergillus niger UFV-1 phytase was characterized and made available for industrial application. The enzyme was purified via ultrafiltration followed by acid precipitation, ion exchange and gel filtration chromatography. This protein exhibited a molecular mass of 161 kDa in gel filtration and 81 kDa in sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), indicating that it may be a dimer. It presented an optimum temperature of 60 °C and optimum pH of 2.0. The KM for sodium phytate hydrolysis was 30.9 mM, while the kcat and kcat/KM were 1.46 ×105 s−1 and 4.7 × 106 s−1.M−1, respectively. The purified phytase exhibited broad specificity on a range of phosphorylated compounds, presenting activity on sodium phytate, p-NPP, 2- naphthylphosphate, 1- naphthylphosphate, ATP, phenyl-phosphate, glucose-6-phosphate, calcium phytate and other substrates. Enzymatic activity was slightly inhibited by Mg2+, Cd2+, K+ and Ca2+, and it was drastically inhibited by F−. The enzyme displayed high thermostability, retaining more than 90% activity at 60 °C during 120 h and displayed a t1/2 of 94.5 h and 6.2 h at 70 °C and 80 °C, respectively. The enzyme demonstrated strong resistance toward pepsin and trypsin, and it retained more than 90% residual activity for both enzymes after 1 h treatment. Additionally, the enzyme efficiently hydrolyzed phytate in livestock feed, liberating 15.3 μmol phosphate/mL after 2.5 h of treatment.


Assuntos
/isolamento & purificação , /metabolismo , Aspergillus niger/enzimologia , /química , Precipitação Química , Cromatografia em Gel , Cromatografia por Troca Iônica , Eletroforese em Gel de Poliacrilamida , Estabilidade Enzimática , Inibidores Enzimáticos/análise , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Peso Molecular , Multimerização Proteica , Proteólise , Peptídeo Hidrolases/metabolismo , Ácido Fítico/metabolismo , Especificidade por Substrato , Temperatura , Ultrafiltração
12.
Dental press j. orthod. (Impr.) ; 20(2): 35-41, Mar-Apr/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-745851

RESUMO

OBJECTIVE: The aim of the present study was to evaluate, comparatively, the periodontal response during orthodontic treatment performed with self-ligating and conventional brackets. METHODS: Sixteen Caucasian individuals of both sexes, aged between 12 and 16 years old and in permanent dentition were selected. Eight individuals were treated with conventional brackets installed on the lower dental arch and self-ligating brackets on the upper arch. Another eight individuals received self-ligating brackets in the lower arch and conventional brackets in the upper arch. The subjects received material and instructions for oral hygiene. Visible plaque index (VPI), gingival bleeding index (GBI) and clinical attachment level (CAL) were evaluated just after installation of orthodontic appliances, and 30, 60 and 180 days later. Mann-Whitney test was used to compare differences between groups (self-ligating and conventional), two-way ANOVA followed by Tukey's test was used to assess CAL at each site of each tooth. Significance level was set at 5%. RESULTS: No significant changes were found with regard to the assessed parameters (VPI, GBI and CAL) in either one of the systems. CONCLUSION: No significant changes were found with regard to the periodontal response to orthodontic treatment for the variables assessed and between subjects receiving passive self-ligating and conventional brackets. All individuals had received oral hygiene instructions and had their periodontal conditions monitored. .


OBJETIVO: o objetivo do presente estudo foi avaliar, comparativamente, a resposta periodontal durante o tratamento ortodôntico realizado com braquetes autoligáveis e convencionais. MÉTODOS: dezesseis indivíduos, leucodermas, em dentição permanente, de ambos os sexos, com idades de 12 a 16 anos, foram selecionados. Oito foram tratados com braquetes convencionais instalados na arcada inferior, e braquetes autoligáveis na arcada superior. Os outros oito indivíduos receberam braquetes autoligáveis na arcada inferior e braquetes convencionais na arcada superior. Os pacientes receberam materiais e instruções sobre higiene bucal. O índice de placa visível (IPV), o índice de sangramento gengival (ISG) e o nível de inserção clínica (NIC) foram avaliados logo após a instalação do aparelho e 30, 60 e 180 dias mais tarde. Para comparar as diferenças entre os grupos (braquetes autoligáveis e convencionais), foi utilizado o teste Mann-Whitney; para analisar o NIC em cada local de cada dente, foi utilizada a análise de variância de duas vias, seguida do teste de Tukey, com nível de significância a 5%. RESULTADOS: não houve alteração significativa nos parâmetros avaliados (IPV, ISG e NIC), em nenhum dos dois sistemas. CONCLUSÃO: a resposta periodontal ao tratamento ortodôntico não apresentou diferenças significativas, para nenhuma das variáveis analisadas, entre os indivíduos tratados com braquetes autoligáveis passivos e braquetes convencionais, os quais receberam instruções quanto à adequada higienização bucal e foram submetidos ao monitoramento das condições periodontais. .


Assuntos
Animais , Humanos , Transportador de Glucose Tipo 1/metabolismo , Neoplasias/metabolismo , Ilhas de CpG , Metilação de DNA , Regulação Neoplásica da Expressão Gênica , Glicólise , Transportador de Glucose Tipo 1/genética , Camundongos Nus , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Neoplasias/genética , Oxigênio/metabolismo , Regiões Promotoras Genéticas , Proteólise
13.
Rev. latinoam. enferm ; 23(2): 329-336, Feb-Apr/2015. graf
Artigo em Inglês | LILACS, BDENF - Enfermagem | ID: lil-747176

RESUMO

OBJECTIVE: to analyze the socio-familial and community inclusion and social participation of people with disabilities, as well as their inclusion in occupations in daily life. METHOD: qualitative study with data collected through open interviews concerning the participants' life histories and systematic observation. The sample was composed of ten individuals with acquired or congenital disabilities living in the region covered by a Family Health Center. The social conception of disability was the theoretical framework used. Data were analyzed according to an interpretative reconstructive approach based on Habermas' Theory of Communicative Action. RESULTS: the results show that the socio-familial and community inclusion of the study participants is conditioned to the social determinants of health and present high levels of social inequality expressed by difficult access to PHC and rehabilitation services, work and income, education, culture, transportation and social participation. CONCLUSION: there is a need to develop community-centered care programs in cooperation with PHC services aiming to cope with poverty and improve social inclusion. .


OBJETIVO: analisar a inclusão sociofamiliar e comunitária e a participação social de pessoas com deficiência, bem como sua inserção em ocupações na vida cotidiana. MÉTODO: estudo qualitativo, com coleta de dados por meio de entrevistas abertas sobre história de vida e observação sistemática. A amostra foi composta por dez pessoas com deficiência, adquirida ou congênita, moradoras de região adstrita a um Núcleo de Saúde da Família. O referencial teórico foi a concepção social da deficiência. Os dados foram analisados segundo abordagem interpretativa reconstrutiva, fundamentada no referencial da Teoria da Ação Comunicativa de Habermas. RESULTADOS: os resultados evidenciaram que a inclusão sociofamiliar e comunitária dos sujeitos do estudo condiciona-se a determinantes sociais da saúde, apresentando índices de iniquidades sociais, expressos pela dificuldade de acesso a serviços de Atenção Primária à Saúde e de reabilitação, trabalho e renda, educação, cultura, transporte e participação social. CONCLUSÃO: conclui-se a necessidade da elaboração de programas de atenção centrados na comunidade, voltados ao enfrentamento da pobreza e à inclusão social, em articulação com serviços de Atenção Primaria à Saúde. .


OBJETIVO: analizar la inclusión social familiar y comunitaria, y la participación social de personas con deficiencia, así como su inserción en ocupaciones en la vida cotidiana. MÉTODO: estudio cualitativo, con recolección de datos por medio de entrevistas abiertas sobre historia de vida y por observación sistemática. La muestra estuvo compuesta por diez personas con deficiencia, adquirida o congénita, habitantes de una región adscrita a un Núcleo de Salud de la Familia. El referencial teórico fue la concepción social de la deficiencia. Los datos fueron analizados según abordaje interpretativo reconstructivo, fundamentado en el referencial de la Teoría de la Acción Comunicativa de Habermas. RESULTADOS: los resultados evidenciaron que la inclusión social familiar y comunitaria de los sujetos del estudio se condiciona a determinantes sociales de la salud, presentando índices de iniquidades sociales, expresados por la dificultad de acceso a servicios de Atención Primaria de la Salud y de rehabilitación, trabajo y renta, educación, cultura, transporte y participación social. CONCLUSIÓN: se concluye que existe la necesidad de elaborar programas de atención centrados en la comunidad, dirigidos al enfrentamiento de la pobreza y a la inclusión social, en articulación con servicios de Atención Primaria a la Salud. .


Assuntos
Humanos , Animais , Feminino , Camundongos , Antineoplásicos/farmacologia , Proteínas de Choque Térmico HSP90/metabolismo , Lactonas/farmacologia , /tratamento farmacológico , Oximas/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Camundongos Nus , Camundongos Transgênicos , /metabolismo , Proteólise , Transcriptoma/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Mem. Inst. Oswaldo Cruz ; 110(1): 65-74, 03/02/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-741608

RESUMO

Aiming to identify new sources of bioactive secondary metabolites, we isolated 82 endophytic fungi from stems and barks of the native Brazilian tree Caesalpinia echinata Lam. (Fabaceae). We tested their ethyl acetate extracts in several in vitro assays. The organic extracts from three isolates showed antibacterial activity against Staphylococcus aureus and Escherichia coli [minimal inhibitory concentration (MIC) 32-64 μg/mL]. One isolate inhibited the growth of Salmonella typhimurium (MIC 64 μg/mL) and two isolates inhibited the growth of Klebsiella oxytoca (MIC 64 μg/mL), Candida albicans and Candida tropicalis (MIC 64-128 μg/mL). Fourteen extracts at a concentration of 20 μg/mL showed antitumour activities against human breast cancer and human renal cancer cells, while two isolates showed anti-tumour activities against human melanoma cancer cells. Six extracts were able to reduce the proliferation of human peripheral blood mononuclear cells, indicating some degree of selective toxicity. Four isolates were able to inhibit Leishmania (Leishmania) amazonensis and one isolate inhibited Trypanosoma cruzi by at least 40% at 20 μg/mL. The trypanocidal extract obtained from Fusarium sp. [KF611679] culture was subjected to bioguided fractionation, which revealed beauvericin as the compound responsible for the observed toxicity of Fusarium sp. to T. cruzi. This depsipeptide showed a half maximal inhibitory concentration of 1.9 μg/mL (2.43 μM) in a T. cruzi cellular culture assay.


Assuntos
Animais , Humanos , Antibacterianos/isolamento & purificação , Conservantes de Alimentos/isolamento & purificação , Myrica/química , Perciformes/microbiologia , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Alimentos Marinhos/microbiologia , Antibacterianos/efeitos adversos , Antibacterianos/química , China , Qualidade dos Alimentos , Armazenamento de Alimentos , Conservantes de Alimentos/efeitos adversos , Conservantes de Alimentos/química , Doenças Transmitidas por Alimentos/microbiologia , Doenças Transmitidas por Alimentos/prevenção & controle , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/crescimento & desenvolvimento , Bactérias Gram-Positivas/isolamento & purificação , Concentração de Íons de Hidrogênio , Peroxidação de Lipídeos , Testes de Sensibilidade Microbiana , Oceano Pacífico , Proteólise , Extratos Vegetais/efeitos adversos , Extratos Vegetais/química , Alimentos Marinhos/análise
16.
Rev. bras. ciênc. vet ; 22(3-4): 220-223, jul.-dez.2015. il.
Artigo em Português | LILACS | ID: biblio-998712

RESUMO

A proteólise do leite e da bebida láctea UAT durante a estocagem é um dos fatores mais importantes na determinação da validade comercial desses. O teor de glicomacropeptídeos (GMP) é um marcador das ações proteolíticas no leite, pois é capaz de indicar indiretamente a integridade da κ-caseína. Assim, no presente trabalho, objetivou-se avaliar a proteólise da κ-caseína do leite e da bebida láctea UAT ao longo do período de validade. Foram avaliadas 60 amostras de cinco diferentes marcas comerciais de cada produto através do método espectrofotométrico para quantificação de ácido siálico. Para o leite UAT foi observado o intervalo entre 3,83 e 15,27 µg de ácido siálico/mL no início do período de validade (D0), 5,95 a 17,16 µg de ácido siálico/mL 60 dias após o início do período (D60) e 6,54 a 21,11 µg de ácido siálico/mL no final do período, ou seja, 120 dias após (D120) a produção. Já para as bebidas lácteas foram observados intervalos entre 11,12 e 24,25; 15,74 e 24,73 e 17,19 e 26,49 µg de ácido siálico/mL para o dia inicial, 60 e 120 dias do período de validade, respectivamente. Os valores obtidos para o índice proteolítico do leite e bebida láctea UAT aumentaram gradativamente ao longo do período de validade dos produtos, sendo tal diferença detectável a partir de sessenta dias. Não foi observada influência da abertura da embalagem na proteólise da k-caseína.


The UHT milk and milk beverage proteolysis during storage is the major factor that limits the shelf-life of these products. The GMP content has assumed importance because it can indirectly indicate the integrity of κ-casein in milk. So, this study focused on evaluates the κ-casein proteolysis in UHT milk and milk beverage during the shelf-life. 60 samples obtained of five different brands of each product were evaluated by spectrophotometric assay for quantifying acid sialic. For UHT milk was observed the values ranging from 3.83 to 15.27 µg acid sialic/ml at the begin of the shelf-life, from 5.95 to 17.16 mg sialic acid/ml at the middle of the period (60 days after the production) and 6.54 to 21.11 mg sialic acid/ml at the end of shelf-life (120 days). For milk beverages were observed ranges between 11.12 to 24.25, 15.74 to 24.73 µg of sialic acid/ml and from 17.19 to 26.49 mg sialic acid/ml respectively for the beginning, 60 and 120 days of the shelf-life. The proteolysis rate in UHT milk and milk beverage increased during the shelflife and is detectable after 60 days of the shelf-life. The practice of open the package did not influence the κ-casein proteolysis.


Assuntos
Caseínas , Proteólise , Espectrofotometria , Ácido N-Acetilneuramínico
17.
Braz. j. microbiol ; 45(3): 1039-1046, July-Sept. 2014. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-727036

RESUMO

Numerous bacteria coordinate gene expression in response to small signalling molecules in many cases known as acylhomoserine lactones (AHLs), which accumulate as a function of cell density in a process known as quorum sensing. This work aimed to determine if phenotypes that are important to define microbial activity in foods such as biofilm formation, swarming motility and proteolytic activity of two Pseudomonas fluorescens strains, isolated from refrigerated raw milk, are influenced by AHL molecules. The tested P. fluorescens strains did not produce AHL molecules in none of the evaluated media. We found that biofilm formation was dependent on the culture media, but it was not influenced by AHLs. Our results indicate that biofilm formation, swarming motility and proteolytic activity of the tested P. fluorescens strains are not regulated by acyl-homoserine lactones. It is likely that AHL-dependent quorum sensing system is absent from these strains.


Assuntos
Animais , Acil-Butirolactonas/metabolismo , Leite/microbiologia , Pseudomonas fluorescens/isolamento & purificação , Pseudomonas fluorescens/fisiologia , Percepção de Quorum , Biofilmes/crescimento & desenvolvimento , Locomoção , Proteólise
18.
Braz. j. microbiol ; 45(2): 389-393, Apr.-June 2014. ilus
Artigo em Inglês | LILACS | ID: lil-723093

RESUMO

Proteolysis-resistant lipases can be well exploited by industrial processes which employ both lipase and protease as biocatalysts. A proteolysis resistant lipase from Bacillus pumilus SG2 was isolated, purified and characterized earlier. The lipase was resistant to native and commercial proteases. In the present work, we have characterized the lip gene which encodes the proteolysis-resistant lipase from Bacillus pumilus SG2. The parameters and structural details of lipase were analysed. The lip gene consisted of 650 bp. The experimental molecular weight of SG2 lipase was nearly double that of its theoretical molecular weight, thus suggesting the existence of the functional lipase as a covalent dimer. The proteolytic cleavage sites of the lipase would have been made inaccessible by dimerisation, thus rendering the lipase resistant to protease.


Assuntos
Bacillus/enzimologia , Bacillus/genética , Lipase/genética , Lipase/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Lipase/química , Dados de Sequência Molecular , Peso Molecular , Filogenia , Multimerização Proteica , Proteólise , Peptídeo Hidrolases/metabolismo , Homologia de Sequência
19.
Rev. chil. nutr ; 41(1): 77-84, mar. 2014. tab
Artigo em Espanhol | LILACS | ID: lil-710963

RESUMO

A source of dietary fiber obtained from plantain peel (Musa AAB) was characterized in terms of dietary fiber, total phenols and antioxidant capacity in order to generate proposal for use of the byproducts of plantain agribusiness. Thereafter, the effect of the inclusion of the source of dietary fiber was evaluated at levels of0 g, 5.5 g, y 6.5 g (treatment) of adding source of dietary fiber /100 g in a hamburger-type meat product during a time period of 28 days (with sampling on days 0, 7, 14, 21 and 28) on lipid and protein spoilage in terms of malonaldehyde production per gram of meatproduct and volatile nitrogenous bases per 100 g of meat product. Treatments including dietary fiber had no significant effect on lipid degradation (p>0.05) while protein degradation had statistically significant differences (p<0.05), volatile nitrogenous bases values were lower on treatments with 5.5, y 6.5 g of adding source of dietary fiber /100 g in a hamburger. It is concluded that the high fiber source obtained from dietary plantain peels by applied process may be used to increase hamburger's dietary fiber level and to prevent protein degradation.


Con el objetivo de generar una propuesta de aprovechamiento de los subproductos de la agroindustria del plátano, en esta investigación se caracterizó una fuente de fibra dietaria obtenida a partir de cáscara de plátano (Musa AAB) en términos de fibra dietaria, fenoles totales y capacidad antioxidante; posteriormente se evaluó el efecto de la inclusión de la fuente de fibra dietaria a niveles de 0 g, 5,5 g, y 6,5 g de inclusión de la fuente de fibra dietaria /100 g de producto cárnico tipo hamburguesa (tratamientos) durante un periodo de tiempo de 28 días (con muestreos los días 0, 7, 14, 21 y 28) sobre la degradación lipídica y proteica en términos de producción de malonaldehído por gramo de producto cárnico (hamburguesa) y bases nitrogenadas volátiles por cada 100 g de producto cárnico tipo hamburguesa. Los tratamientos con inclusión de fibra dietaria no tuvieron efecto significativo sobre la degradación lipídica (p>0,05) mientras que en la degradación proteica sí se presentaron diferencias estadísticamente significativas (p<0,05) siendo menores los valores de bases nitrogenadas volátiles obtenidos de los tratamientos con 5,5 g, y 6,5 g de inclusión de la fuente de fibra dietaria /100 g de hamburguesa. Se concluye que la fuente de fibra dietaria obtenida a partir de cáscara de plátano mediante el proceso aplicado, puede utilizarse para aumentar el nivel de fibra dietaria en un producto cárnico tipo hamburguesa y para obtener un efecto protector sobre la fracción proteica del producto cárnico.


Assuntos
Fibras na Dieta , Peroxidação de Lipídeos , Musa , Proteólise , Produtos da Carne , Antioxidantes
20.
Braz. j. microbiol ; 44(4): 1299-1304, Oct.-Dec. 2013. ilus
Artigo em Inglês | LILACS | ID: lil-705290

RESUMO

Halophilic microorganisms are source of potential hydrolytic enzymes to be used in industrial and/or biotechnological processes. In the present study, we have investigated the ability of the moderately halophilic bacterium Halobacillus blutaparonensis (strain M9), a novel species described by our group, to release proteolytic enzymes. This bacterial strain abundantly proliferated in Luria-Bertani broth supplemented with 2.5% NaCl as well as secreted proteases to the extracellular environment. The production of proteases occurred in bacterial cells grown under different concentration of salt, ranging from 0.5% to 10% NaCl, in a similar way. The proteases secreted by H. blutaparonensis presented the following properties: (i) molecular masses ranging from 30 to 80 kDa, (ii) better hydrolytic activities under neutral-alkaline pH range, (iii) expression modulated according to the culture age, (iv) susceptibility to phenylmethylsulphonyl fluoride, classifying them as serine-type proteases, (v) specific cleavage over the chymotrypsin substrate, and (vi) enzymatic stability in the presence of salt (up to 20% NaCl) and organic solvents (e.g., ether, isooctane and cyclohexane). The proteases described herein are promising for industrial practices due to its haloalkaline properties.


Assuntos
Halobacillus/enzimologia , Serina Proteases/análise , Meios de Cultura/química , Estabilidade Enzimática , Inibidores Enzimáticos/metabolismo , Concentração de Íons de Hidrogênio , Halobacillus/crescimento & desenvolvimento , Peso Molecular , Proteólise , Fluoreto de Fenilmetilsulfonil/metabolismo , Serina Proteases/química , Cloreto de Sódio/metabolismo
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