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1.
Anim. Reprod. (Online) ; 19(4): e20220010, 2022. tab
Artigo em Inglês | VETINDEX | ID: biblio-1403212

Resumo

The aim of this study was to evaluate the association of different concentrations of Trolox® and the addition of a fixed concentration of DHA in the freezing of semen of Mangalarga Marchador stallions. To that end, 16 ejaculates were frozen in the following extenders: E1) BotuCrio® (BC; Control); E2) BC + 50 ngml-1 DHA + 30 µM Trolox® (BCDHA30T); E3) BC + 50 ngml-1 DHA + 40 µM Trolox® (BCDHA40T); E4) BC + 50 ngml-1 DHA + 50 µM Trolox® (BCDHA50T). All the tested extenders were similar in preserving different kinematic parameters, cell functional integrity, compacted DNA, and high and intermediate mitochondrial activity (P>0.05). However, sperm cryopreserved in BCDHA40T showed higher velocities than sperm frozen in the control extender (P<0.05). The 30 µM concentration of Trolox® was worse for sperm motility and the 50 µM concentration of Trolox® did not adequately preserve the structural integrity of the membranes in an extender containing DHA when compared to the BotuCrio® (P<0.05) extender. The use of Trolox® in freezing extenders containing DHA did not maximize the effect of BotuCrio®, except for in the case of sperm velocity parameters when at a concentration of 40 µM.(AU)


Assuntos
Animais , Masculino , Preservação do Sêmen/veterinária , Criopreservação/métodos , Ácidos Docosa-Hexaenoicos/administração & dosagem , Capacidade de Absorbância de Radicais de Oxigênio , Cavalos/fisiologia
2.
Semina ciênc. agrar ; 43(4): 1637-1652, jul.-ago. 2022. graf
Artigo em Inglês | VETINDEX | ID: biblio-1369839

Resumo

Lactose is the main carbohydrate in milk, and its absorption occurs via enzymatic hydrolysis, generating glucose and galactose. Lactose intolerance is the reduction of intestinal hydrolysis capacity due to hypolactasia, which results in the need to consume dairy foods with low levels of this carbohydrate. ß-galactosidase enzymes are used in dairy industries to hydrolyze lactose, thereby allowing intolerant consumers access to dairy products without the negative health implications. Alternative and official analytical methods are used to quantify the carbohydrate content resulting from enzymatic hydrolysis. The objective of this study was to evaluate the enzymatic hydrolysis of two distinct industrial enzymes produced by the microorganisms Bacillus licheniformis and Kluyveromyces lactis using three analytical methods: enzymatic method, cryoscopy, and high performance liquid chromatography (HPLC) using artificial intelligence to improve the control of the industrial processes. After adding the enzymes to skim milk, time kinetics was performed by collecting samples at time 0, every 10 min for 1 h, and every 30 min until the end of 5 h of hydrolysis. In 97% of the cases, a decrease in lactose concentration was observed by HPLC, followed by the deepening of the cryoscopic point. Glucose measurements by absorbance and HPLC quantification were correlated (r = 0.79; p < 0.01) but not concordant (p < 0.01). It was concluded that by means of artificial intelligence, it was possible to indirectly estimate lactose concentration using an algorithm that associates cryoscopy and glucose concentration.(AU)


O principal carboidrato do leite é a lactose e a sua absorção ocorre devido à hidrólise enzimática, gerando glicose e galactose. A intolerância à lactose é a redução da capacidade de hidrólise intestinal devido à hipolactasia, gerando a necessidade do consumo de alimentos lácteos com baixo teor deste carboidrato. As enzimas ß-galactosidase são utilizadas nas indústrias de laticínios para hidrolisar a lactose, proporcionando ao consumidor intolerante a possibilidade de ingerir os produtos lácteos sem prejuízos à saúde. Para quantificar o conteúdo de carboidratos resultante da hidrólise enzimática, são utilizados métodos analíticos alternativos e oficiais. O objetivo deste estudo foi avaliar a hidrólise enzimática de duas enzimas industriais distintas produzidas pelos microrganismos Bacillus licheniformis e Kluyveromyces lactis, por meio de três métodos analíticos: método enzimático, crioscopia e HPLC. A inteligência artificial foi utilizada para melhorar o controle dos processos industriais. Após a adição das enzimas ao leite desnatado, foi realizada a cinética de tempo coletando as amostras no tempo 0, a cada 10 minutos, até completar 1 hora de reação, e a cada 30 minutos até serem atingidas 5 horas de reação de hidrólise. Em 97% dos casos, a diminuição da concentração de lactose por HPLC acompanhou o aprofundamento do ponto crioscópico. As medições de glicose por absorbância e HPLC foram correlacionadas (r = 0,79; p < 0,01), mas não concordantes (p < 0,01). Concluiu-se que, por meio da inteligência artificial, é possível estimar indiretamente a concentração de lactose a partir de um algoritmo que associa a crioscopia e a concentração de glicose.(AU)


Assuntos
Inteligência Artificial , Hidrólise , Lactose , Kluyveromyces , Bacillus licheniformis
3.
Acta sci., Biol. sci ; 43: e51737, 2021. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1460974

Resumo

Endophytes are growth-promoting agents capable of synthesizing phytohormones, uptaking nutrients, and controlling pathogens. There is a strong potential to exploit them in the agriculture field like biofertilizers and biocontrol agents. In this work, we aimed to evaluate endophytic fungi isolated from Pachystachys lutea for their potential to solubilize phosphate, synthesise indole acetic acid (IAA), antagonize phytopathogens, and promote plant growth under greenhouse conditions. The phosphate solubilization efficiency was assessed on Pikovskaya’s agar medium. For analysis of IAA production, mycelia plugs of endophytes were cultured in Potato Dextrose Broth medium supplemented with L-tryptophan, with Salkowski Reagent, and the absorbance of the culture was measured. The antagonism evaluation of strain Alternaria sp. PL75 against phytopathogens was performed using the paired-culture technique. The promotion of plant growth provided by Alternaria sp. PL75 was evaluated in tomato plants. All strains evaluated were able to solubilize phosphate; however, the strain Alternaria sp. PL75 was the most effective (4.29). Two strains, Nemania sp. PL27 and Alternaria sp. PL75, produced 1.86 and 1.73 & 956;g mL-1 of IAA, respectively. In the antagonism assay, the endophyte Alternaria sp. PL75 and its fungal extract showed the best results against the pathogen Moniliophthora perniciosa. The greenhouse experiment result showed the endophyte Alternaria sp. PL75 increased the plantlets emergency speed index and the percentage of germination from 60 to 81.63%. It was also observed a statistical significance in the shoot length of the treated plants with the endophyte suspension (55.38 cm) compared to the control (41.67 cm).


Assuntos
Endófitos , Fosfatos , Lamiales/crescimento & desenvolvimento , Ácido Acético/análise
4.
Acta Sci. Biol. Sci. ; 43: e51737, 2021. tab, ilus
Artigo em Inglês | VETINDEX | ID: vti-764583

Resumo

Endophytes are growth-promoting agents capable of synthesizing phytohormones, uptaking nutrients, and controlling pathogens. There is a strong potential to exploit them in the agriculture field like biofertilizers and biocontrol agents. In this work, we aimed to evaluate endophytic fungi isolated from Pachystachys lutea for their potential to solubilize phosphate, synthesise indole acetic acid (IAA), antagonize phytopathogens, and promote plant growth under greenhouse conditions. The phosphate solubilization efficiency was assessed on Pikovskayas agar medium. For analysis of IAA production, mycelia plugs of endophytes were cultured in Potato Dextrose Broth medium supplemented with L-tryptophan, with Salkowski Reagent, and the absorbance of the culture was measured. The antagonism evaluation of strain Alternaria sp. PL75 against phytopathogens was performed using the paired-culture technique. The promotion of plant growth provided by Alternaria sp. PL75 was evaluated in tomato plants. All strains evaluated were able to solubilize phosphate; however, the strain Alternaria sp. PL75 was the most effective (4.29). Two strains, Nemania sp. PL27 and Alternaria sp. PL75, produced 1.86 and 1.73 & 956;g mL-1 of IAA, respectively. In the antagonism assay, the endophyte Alternaria sp. PL75 and its fungal extract showed the best results against the pathogen Moniliophthora perniciosa. The greenhouse experiment result showed the endophyte Alternaria sp. PL75 increased the plantlets emergency speed index and the percentage of germination from 60 to 81.63%. It was also observed a statistical significance in the shoot length of the treated plants with the endophyte suspension (55.38 cm) compared to the control (41.67 cm).(AU)


Assuntos
Lamiales/crescimento & desenvolvimento , Endófitos , Ácido Acético/análise , Fosfatos
5.
Braz. J. Biol. ; 81(2): 387-391, Mar.-May 2021. ilus, tab
Artigo em Inglês | VETINDEX | ID: vti-762739

Resumo

Poor storage conditions provide favorable environment to stored grain pests for their growth. The bio-pesticides are the best alternatives to synthetic pesticides. Present study was conducted to compare toxicity of Rubus fruticosus and Valeriana jatamansi against granary weevil, Sitophilus granarius and subsequent changes in enzyme activity responsible for grain damage. In current research 5 g of R. fruticosus fruit and V. jatamansi rhizome powders were tested separately against S. granarius, in 50 g wheat whole grains for seven days in comparison with the control. The enzymatic activity of malate dehydrogenase and alpha-amylase was observed in the cellular extracts of S. granarius. The insects were crushed and homogenized in phosphate-buffer solution and centrifuged at 10000 rpm for 5 minutes. For the enzymatic measurement supernatant was tested; the spectrophotometer was adjusted at 340 nm. The reagents were mixed and incubated at 25 °C for five minutes. The cuvettes were placed in the experimental and reference sites of spectrophotometer and recorded the change in absorbance for 3-4 minutes. There was 5.60% and 14.92% reduction in the activity of malate dehydrogenase in R. fruticosus and V. jatamansi, treated insects, respectively. The alpha amylase enzyme activity was 6.82% reduced and 63.63% increase in R. fruticosus and V. jatamansi, treated insects, respectively. Present study addresses that both plant powders are effective against granary weevil by altering enzyme activities so both the plant powders can be used as bio-pesticides against the stored grains pests.(AU)


As más condições de armazenamento proporcionam um ambiente favorável às pragas armazenadas para o crescimento. Os biopesticidas são as melhores alternativas aos pesticidas sintéticos. O presente estudo foi conduzido para comparar a toxicidade de Rubus fruticosus e Valeriana jatamansi contra gorgulhos, Sitophilus granarius e subsequentes alterações na atividade enzimática responsáveis por danos aos grãos. Na pesquisa atual, 5 g de frutos de R. fruticosus e pós de rizoma de V. jatamansi foram testados separadamente contra S. granarius, em 50 g de grãos integrais de trigo por sete dias, em comparação com o controle. A atividade enzimática da malato desidrogenase e alfa-amilase foi observada nos extratos celulares de S. granarius. Os insetos foram esmagados e homogeneizados em solução tampão fosfato e centrifugados a 10000 rpm por 5 minutos. Para a medição enzimática, o sobrenadante foi testado; o espectrofotômetro foi ajustado a 340 nm. Os reagentes foram misturados e incubados a 25 °C por cinco minutos. As cubetas foram colocadas nos locais experimentais e de referência do espectrofotômetro e registradas as alterações na absorbância por 3-4 minutos. Houve redução de 5,60% e 14,92% na atividade da malato desidrogenase em R. fruticosus e V. jatamansi, insetos tratados, respectivamente. A atividade da enzima alfa amilase foi reduzida em 6,82% e aumento de 63,63% em R. fruticosus e V. jatamansi, insetos tratados, respectivamente. O presente estudo aborda que ambos os pós de plantas são eficazes contra o gorgulho do celeiro, alterando as atividades enzimáticas, de modo que ambos os pós de plantas possam ser usados como biopesticidas contra pragas de grãos armazenados.(AU)


Assuntos
Malato Desidrogenase , alfa-Amilases , Rubus , Gorgulhos , Valeriana , Controle Biológico de Vetores
6.
Braz. j. biol ; 81(2): 387-391, 2021. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1153349

Resumo

Poor storage conditions provide favorable environment to stored grain pests for their growth. The bio-pesticides are the best alternatives to synthetic pesticides. Present study was conducted to compare toxicity of Rubus fruticosus and Valeriana jatamansi against granary weevil, Sitophilus granarius and subsequent changes in enzyme activity responsible for grain damage. In current research 5 g of R. fruticosus fruit and V. jatamansi rhizome powders were tested separately against S. granarius, in 50 g wheat whole grains for seven days in comparison with the control. The enzymatic activity of malate dehydrogenase and α-amylase was observed in the cellular extracts of S. granarius. The insects were crushed and homogenized in phosphate-buffer solution and centrifuged at 10000 rpm for 5 minutes. For the enzymatic measurement supernatant was tested; the spectrophotometer was adjusted at 340 nm. The reagents were mixed and incubated at 25 °C for five minutes. The cuvettes were placed in the experimental and reference sites of spectrophotometer and recorded the change in absorbance for 3-4 minutes. There was 5.60% and 14.92% reduction in the activity of malate dehydrogenase in R. fruticosus and V. jatamansi, treated insects, respectively. The alpha amylase enzyme activity was 6.82% reduced and 63.63% increase in R. fruticosus and V. jatamansi, treated insects, respectively. Present study addresses that both plant powders are effective against granary weevil by altering enzyme activities so both the plant powders can be used as bio-pesticides against the stored grains pests.


As más condições de armazenamento proporcionam um ambiente favorável às pragas armazenadas para o crescimento. Os biopesticidas são as melhores alternativas aos pesticidas sintéticos. O presente estudo foi conduzido para comparar a toxicidade de Rubus fruticosus e Valeriana jatamansi contra gorgulhos, Sitophilus granarius e subsequentes alterações na atividade enzimática responsáveis ​​por danos aos grãos. Na pesquisa atual, 5 g de frutos de R. fruticosus e pós de rizoma de V. jatamansi foram testados separadamente contra S. granarius, em 50 g de grãos integrais de trigo por sete dias, em comparação com o controle. A atividade enzimática da malato desidrogenase e α-amilase foi observada nos extratos celulares de S. granarius. Os insetos foram esmagados e homogeneizados em solução tampão fosfato e centrifugados a 10000 rpm por 5 minutos. Para a medição enzimática, o sobrenadante foi testado; o espectrofotômetro foi ajustado a 340 nm. Os reagentes foram misturados e incubados a 25 °C por cinco minutos. As cubetas foram colocadas nos locais experimentais e de referência do espectrofotômetro e registradas as alterações na absorbância por 3-4 minutos. Houve redução de 5,60% e 14,92% na atividade da malato desidrogenase em R. fruticosus e V. jatamansi, insetos tratados, respectivamente. A atividade da enzima alfa amilase foi reduzida em 6,82% e aumento de 63,63% em R. fruticosus e V. jatamansi, insetos tratados, respectivamente. O presente estudo aborda que ambos os pós de plantas são eficazes contra o gorgulho do celeiro, alterando as atividades enzimáticas, de modo que ambos os pós de plantas possam ser usados ​​como biopesticidas contra pragas de grãos armazenados.


Assuntos
Animais , Valeriana/toxicidade , Gorgulhos , Agentes de Controle Biológico/administração & dosagem , Rubus/toxicidade , Controle Biológico de Vetores/métodos , alfa-Amilases , Armazenamento de Alimentos/normas , Malato Desidrogenase
7.
Artigo em Inglês | VETINDEX | ID: vti-745564

Resumo

Abstract Poor storage conditions provide favorable environment to stored grain pests for their growth. The bio-pesticides are the best alternatives to synthetic pesticides. Present study was conducted to compare toxicity of Rubus fruticosus and Valeriana jatamansi against granary weevil, Sitophilus granarius and subsequent changes in enzyme activity responsible for grain damage. In current research 5 g of R. fruticosus fruit and V. jatamansi rhizome powders were tested separately against S. granarius, in 50 g wheat whole grains for seven days in comparison with the control. The enzymatic activity of malate dehydrogenase and -amylase was observed in the cellular extracts of S. granarius. The insects were crushed and homogenized in phosphate-buffer solution and centrifuged at 10000 rpm for 5 minutes. For the enzymatic measurement supernatant was tested; the spectrophotometer was adjusted at 340 nm. The reagents were mixed and incubated at 25 °C for five minutes. The cuvettes were placed in the experimental and reference sites of spectrophotometer and recorded the change in absorbance for 3-4 minutes. There was 5.60% and 14.92% reduction in the activity of malate dehydrogenase in R. fruticosus and V. jatamansi, treated insects, respectively. The alpha amylase enzyme activity was 6.82% reduced and 63.63% increase in R. fruticosus and V. jatamansi, treated insects, respectively. Present study addresses that both plant powders are effective against granary weevil by altering enzyme activities so both the plant powders can be used as bio-pesticides against the stored grains pests.


Resumo As más condições de armazenamento proporcionam um ambiente favorável às pragas armazenadas para o crescimento. Os biopesticidas são as melhores alternativas aos pesticidas sintéticos. O presente estudo foi conduzido para comparar a toxicidade de Rubus fruticosus e Valeriana jatamansi contra gorgulhos, Sitophilus granarius e subsequentes alterações na atividade enzimática responsáveis por danos aos grãos. Na pesquisa atual, 5 g de frutos de R. fruticosus e pós de rizoma de V. jatamansi foram testados separadamente contra S. granarius, em 50 g de grãos integrais de trigo por sete dias, em comparação com o controle. A atividade enzimática da malato desidrogenase e -amilase foi observada nos extratos celulares de S. granarius. Os insetos foram esmagados e homogeneizados em solução tampão fosfato e centrifugados a 10000 rpm por 5 minutos. Para a medição enzimática, o sobrenadante foi testado; o espectrofotômetro foi ajustado a 340 nm. Os reagentes foram misturados e incubados a 25 °C por cinco minutos. As cubetas foram colocadas nos locais experimentais e de referência do espectrofotômetro e registradas as alterações na absorbância por 3-4 minutos. Houve redução de 5,60% e 14,92% na atividade da malato desidrogenase em R. fruticosus e V. jatamansi, insetos tratados, respectivamente. A atividade da enzima alfa amilase foi reduzida em 6,82% e aumento de 63,63% em R. fruticosus e V. jatamansi, insetos tratados, respectivamente. O presente estudo aborda que ambos os pós de plantas são eficazes contra o gorgulho do celeiro, alterando as atividades enzimáticas, de modo que ambos os pós de plantas possam ser usados como biopesticidas contra pragas de grãos armazenados.

8.
Ci. Rural ; 50(1): e20190506, Jan. 31, 2020. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-25091

Resumo

Among the soil constituents, special attention is given to soil organic matter (SOM) and clay contents, since, among other aspects, they are key factors to nutrient retention and soil aggregates formation, which directly affect the crop production potential. The methods commonly used for the quantification of these constituents have some disadvantages, such as the use of chemical reactants and waste generation. An alternative to these methods is the near-infrared spectroscopy (NIRS) technique. The aim of this research is to evaluate models for SOM and clay quantification in soil samples using spectral data by NIRS. A set (n = 400) of soil samples previously analyzed by traditional methods were used to generate a NIRS calibration curve. The clay content was determined by the hydrometer method while SOM content was determined by sulfochromic solution. For calibration, we used the original spectra (absorbance) and spectral pretreatment (Savitzky-Golay smoothing derivative) in the following models: multiple linear regression (MLR), partial last squares regression (PLSR), support vector machine (SVM) and Gaussian process regression (GPR). The curve validation was performed with the SVM model (best performance in the calibration based on R² and RMSE) in two ways: with 40 random samples from the calibration set and another set with 200 new unknown samples. The soil clay content affects the predictive ability of the calibration curve to estimate SOM content by NIRS. Validation curves showed poorer performance (lower R² and higher RMSE) when generated from unknown samples, where the model tends to overestimate the lower levels and to underestimate the higher levels of clay and SOM. Despite the potential of NIRS technique to predict these attributes, further calibration studies are still needed to use this technique in soil analysis laboratories.(AU)


Dentre os constituintes do solo, especial atenção é voltada aos teores de argila e de matéria orgânica do solo (MOS), pois, entre outros aspectos, são determinantes para retenção de nutrientes e a formação de agregados no solo, os quais afetam diretamente o potencial produtivo das culturas. Os métodos mais comumente utilizados para quantificação destes constituintes apresentam algumas desvantagens, como o uso de reagentes químicos e a geração de resíduos. Uma alternativa a estes métodos é o uso da espectroscopia no infravermelho próximo (near infrared spectroscopy - NIRS). O objetivo deste trabalho é avaliar modelos de quantificação dos teores de argila e de MOS em amostras de solo utilizando dados espectrais por meio da técnica NIRS. Foram utilizadas 400 amostras de solos com amplitude nos teores de MOS e argila para geração de uma curva de calibração. A argila foi determinada pelo método do densímetro e a MOS por meio da solução sulfocrômica. Para calibração, utilizou-se os espectros originais (absorbância) e com pré-tratamento espectral (Savitzky-Golay derivative) das 400 amostras nos seguintes modelos: multiple linear regression (MLR), partial last squares regression (PLSR), support vector machine (SVM) e Gaussian process regression (GPR). A validação da curva foi realizada com o modelo que apresentou melhor desempenho na calibração (SVM) de duas maneiras: com 40 amostras aleatórias oriundas daquelas utilizadas na calibração e com outras 200 novas amostras desconhecidas. O teor de argila das amostras de solo afeta a capacidade preditiva da curva de calibração da estimativa do teor de MOS pelo NIRS. A validação das curvas apresentou pior desempenho (menor R² e maior RMSE) quando feita a partir de amostras desconhecidas, cujo modelo tende a superestimar os teores mais baixos e subestimar os teores mais elevados de argila e MOS...(AU)


Assuntos
Características do Solo/análise , Química do Solo/análise , Argila , Matéria Orgânica/análise , Espectroscopia de Luz Próxima ao Infravermelho
9.
Ciênc. Anim. (Impr.) ; 29(1,supl.1): 55-59, 2019. ilus
Artigo em Português | VETINDEX | ID: biblio-1472479

Resumo

A dengue é um problema grave para a saúde pública no Brasil e vários fatores agravam a situação, um deles é que a dengue pode ser confundida com outras doenças infecciosas. Este trabalho teve como objetivo a produção de um polipetídeo quimérico do vírus da dengue para a produção de um kit de imunodiagnóstico de baixo custo. Foi usada a proteína E do envelope viral do domínio III, fusionada ao Polipeptídeo Elastina-Like (ELP), a expressão foi feita em N. benthamiana. Os resultados do Western blotting mostraram que a fusão com a cauda de ELP foi melhor expressa do que a não fusionada. O teste de ELISA apresentou diferença significativa nas médias de absorbância entre pacientes positivos e negativos para dengue e de diferenciar pacientes com dengue positivo e de zika positivo, cujo os resultados de absorbâncias se equipararam aos resultados de pacientes negativos.


Dengue is a serious problem for public health in Brazil and several factors aggravate the situation, one of which is that dengue can be mistaken for other infectious diseases. This work aimed at the production of a chimeric dengue virus polypeptide for the production of a low cost immunodiagnostic kit. Domain E viral envelope protein E, fused to the Elastin-Like Polypeptide (ELP), was used in N. benthamiana. Western blotting results showed that fusion with the ELP tail was better expressed than the non-fused. The ELISA test showed a significant difference in the absorbance means between positive and negative patients for dengue and to differentiate patients with dengue positive and positive zika, whose absorbance results were similar to the results of negative patients.


Assuntos
Dengue/diagnóstico , Vírus da Dengue/imunologia , Ensaio de Imunoadsorção Enzimática , Testes Imunológicos/métodos
10.
Ciênc. Anim. (Impr.) ; 29(1,supl.1): 55-59, 2019. ilus
Artigo em Português | VETINDEX | ID: vti-21657

Resumo

A dengue é um problema grave para a saúde pública no Brasil e vários fatores agravam a situação, um deles é que a dengue pode ser confundida com outras doenças infecciosas. Este trabalho teve como objetivo a produção de um polipetídeo quimérico do vírus da dengue para a produção de um kit de imunodiagnóstico de baixo custo. Foi usada a proteína E do envelope viral do domínio III, fusionada ao Polipeptídeo Elastina-Like (ELP), a expressão foi feita em N. benthamiana. Os resultados do Western blotting mostraram que a fusão com a cauda de ELP foi melhor expressa do que a não fusionada. O teste de ELISA apresentou diferença significativa nas médias de absorbância entre pacientes positivos e negativos para dengue e de diferenciar pacientes com dengue positivo e de zika positivo, cujo os resultados de absorbâncias se equipararam aos resultados de pacientes negativos.(AU)


Dengue is a serious problem for public health in Brazil and several factors aggravate the situation, one of which is that dengue can be mistaken for other infectious diseases. This work aimed at the production of a chimeric dengue virus polypeptide for the production of a low cost immunodiagnostic kit. Domain E viral envelope protein E, fused to the Elastin-Like Polypeptide (ELP), was used in N. benthamiana. Western blotting results showed that fusion with the ELP tail was better expressed than the non-fused. The ELISA test showed a significant difference in the absorbance means between positive and negative patients for dengue and to differentiate patients with dengue positive and positive zika, whose absorbance results were similar to the results of negative patients.(AU)


Assuntos
Dengue/diagnóstico , Vírus da Dengue/imunologia , Ensaio de Imunoadsorção Enzimática , Testes Imunológicos/métodos
11.
Acta sci. vet. (Impr.) ; 47: Pub.1654-2019. tab
Artigo em Inglês | VETINDEX | ID: biblio-1458052

Resumo

Background: The genus Salmonella, associated with poultry products, is considered the leading cause of foodborne outbreaks in humans in many countries. In Brazil, Salmonella Enteritidis (SE) is the serovar remains as one most frequentlyisolated from humans, and it is also a major serovar found in animals, food, animal feed, and environmental samples, despiteall the efforts to control this pathogen. Also, the bacterium is able to form biofilms on different surfaces, protecting cellsfrom both cleaning and sanitizing procedures in the food industries. This study aimed to verify the ability of SalmonellaEnteritidis isolates to form biofilm on polystyrene at different incubation temperatures.Materials, Methods & Results: A total of 171 SE samples were isolated from foodborne outbreaks (foods and stool cultures) and poultry products between 2003 and 2010. The biofilm-forming ability of samples was measured at four differenttemperatures (3°C, 9ºC, 25ºC, and 36ºC), for 24 h, simulating temperatures usually found in poultry slaughterhouses. Later,200 μL of each bacterial suspension was inoculated, in triplicate, onto 96-well, flat-bottomed sterile polystyrene microtiterplates, washed, after that, the biofilm was fixed with methanol. The plates were dried at ambient temperature, stained with2% Hucker’s crystal violet. Afterwards, absorbance was read using an ELISA plate reader and the optical density (OD)of each isolate was obtained by the arithmetic mean of the absorbance of three wells and this value was compared withthe mean absorbance of negative controls (ODnc). The following classification was used for the determination of biofilmformation: no biofilm production, weak biofilm production, moderate biofilm production and strong biofilm production.Results demonstrated all isolates from stool cultures and foods involved in foodborne outbreaks, at least one of the fourtemperatures tested, were able to form biofilm...


Assuntos
Animais , Aves Domésticas/microbiologia , Biofilmes , Incrustação Biológica/prevenção & controle , Produtos Avícolas/microbiologia , Refrigeração/veterinária , Salmonella enteritidis , Período de Incubação de Doenças Infecciosas
12.
Acta sci. vet. (Online) ; 47: Pub. 1654, Apr. 22, 2019. tab
Artigo em Inglês | VETINDEX | ID: vti-19104

Resumo

Background: The genus Salmonella, associated with poultry products, is considered the leading cause of foodborne outbreaks in humans in many countries. In Brazil, Salmonella Enteritidis (SE) is the serovar remains as one most frequentlyisolated from humans, and it is also a major serovar found in animals, food, animal feed, and environmental samples, despiteall the efforts to control this pathogen. Also, the bacterium is able to form biofilms on different surfaces, protecting cellsfrom both cleaning and sanitizing procedures in the food industries. This study aimed to verify the ability of SalmonellaEnteritidis isolates to form biofilm on polystyrene at different incubation temperatures.Materials, Methods & Results: A total of 171 SE samples were isolated from foodborne outbreaks (foods and stool cultures) and poultry products between 2003 and 2010. The biofilm-forming ability of samples was measured at four differenttemperatures (3°C, 9ºC, 25ºC, and 36ºC), for 24 h, simulating temperatures usually found in poultry slaughterhouses. Later,200 μL of each bacterial suspension was inoculated, in triplicate, onto 96-well, flat-bottomed sterile polystyrene microtiterplates, washed, after that, the biofilm was fixed with methanol. The plates were dried at ambient temperature, stained with2% Huckers crystal violet. Afterwards, absorbance was read using an ELISA plate reader and the optical density (OD)of each isolate was obtained by the arithmetic mean of the absorbance of three wells and this value was compared withthe mean absorbance of negative controls (ODnc). The following classification was used for the determination of biofilmformation: no biofilm production, weak biofilm production, moderate biofilm production and strong biofilm production.Results demonstrated all isolates from stool cultures and foods involved in foodborne outbreaks, at least one of the fourtemperatures tested, were able to form biofilm...(AU)


Assuntos
Animais , Salmonella enteritidis , Biofilmes , Incrustação Biológica/prevenção & controle , Refrigeração/veterinária , Produtos Avícolas/microbiologia , Aves Domésticas/microbiologia , Período de Incubação de Doenças Infecciosas
13.
Acta sci. vet. (Impr.) ; 47: Pub.1681-2019. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1458080

Resumo

Background: Passive immunity acquired by colostrum ingestion is essential to prevent neonatal infections. Failure ofpassive transfer (FPT) of maternal immunity occurs in foals that fail to absorb enough immunoglobulins within 24 h afterbirth. Foals with FPT are at increased risk of infections and death. Serum samples from neonatal foals might be examinedfor FPT using the zinc sulphate turbidity (ZST) test. The aim of this study was to investigate the accuracy of the ZST test,performed at two different times after first suckling (12 and 18 h), to detect FPT in newborn foals. The effect of temperatureon the turbidity intensity resulting from the ZST reaction was also investigated.Materials, Methods & Results: Blood samples were collected from 112 newborn foals at 12 h after the first colostrumintake. In 36 foals, additional serum samples were collected at 18 h after first colostrum intake. The serum samples weretested with the ZST test and, later, in the laboratory setting, the ZST test was repeated. The IgG levels were measured bysingle radial immunodiffusion (SRID), which was used as the reference method. The standard solution used for the interpretation of results had a turbidity corresponding to approximately 800 mg/dL of immunoglobulins (IgG). The mean IgG concentration measured at 12 and 18 h after the first colostrum intake was analyzed using the t-test for paired samples.Values of absorbance of ZST test under different temperatures were analyzed using a one-way analysis of variance, andmeans were compared using the Tukey test. The relationship between the temperature of the solution and absorbance wasdetermined using the Pearson’s correlation coefficient. Based on SRID results, 12 foals (10.7%) had serum IgG concentration 0.05) between 12 h (943.9 ± 508.6 mg/dL) and 18 h (975.9 ± 525.6 mg/dL)...


Assuntos
Animais , Animais Recém-Nascidos/imunologia , Cavalos/imunologia , Imunidade Materno-Adquirida , Imunoglobulina G , Sulfato de Zinco , Colostro , Testes Imunológicos/veterinária
14.
Acta sci. vet. (Online) ; 47: Pub. 1681, Sept. 25, 2019. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-23846

Resumo

Background: Passive immunity acquired by colostrum ingestion is essential to prevent neonatal infections. Failure ofpassive transfer (FPT) of maternal immunity occurs in foals that fail to absorb enough immunoglobulins within 24 h afterbirth. Foals with FPT are at increased risk of infections and death. Serum samples from neonatal foals might be examinedfor FPT using the zinc sulphate turbidity (ZST) test. The aim of this study was to investigate the accuracy of the ZST test,performed at two different times after first suckling (12 and 18 h), to detect FPT in newborn foals. The effect of temperatureon the turbidity intensity resulting from the ZST reaction was also investigated.Materials, Methods & Results: Blood samples were collected from 112 newborn foals at 12 h after the first colostrumintake. In 36 foals, additional serum samples were collected at 18 h after first colostrum intake. The serum samples weretested with the ZST test and, later, in the laboratory setting, the ZST test was repeated. The IgG levels were measured bysingle radial immunodiffusion (SRID), which was used as the reference method. The standard solution used for the interpretation of results had a turbidity corresponding to approximately 800 mg/dL of immunoglobulins (IgG). The mean IgG concentration measured at 12 and 18 h after the first colostrum intake was analyzed using the t-test for paired samples.Values of absorbance of ZST test under different temperatures were analyzed using a one-way analysis of variance, andmeans were compared using the Tukey test. The relationship between the temperature of the solution and absorbance wasdetermined using the Pearsons correlation coefficient. Based on SRID results, 12 foals (10.7%) had serum IgG concentration < 400 mg and 26 foals (23.2%) had IgG levels between 400 and 800 mg/dL. Serum levels of IgG determined bySRID in 36 foals were similar (P > 0.05) between 12 h (943.9 ± 508.6 mg/dL) and 18 h (975.9 ± 525.6 mg/dL)...(AU)


Assuntos
Animais , Cavalos/imunologia , Sulfato de Zinco , Animais Recém-Nascidos/imunologia , Imunidade Materno-Adquirida , Imunoglobulina G , Testes Imunológicos/veterinária , Colostro
15.
Acta sci. vet. (Impr.) ; 47: Pub.1626-2019. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1458024

Resumo

Background: Mycotoxins produced by yeast and fungi have toxic effects on human and animal health. Aflatoxin B1 (AFB1)is the most toxic hepatocarcinogen to mammals. Aflatoxin M1 (AFM1), which has been found in milk and dairy products,is the hydroxylated metabolite of AFB1. Aflatoxin M1 is formed by the cytochrome P450 enzyme in the liver. OchratoxinA (OTA) is synthesized by Aspergillus and Penicillium species. Ochratoxin A is known to cause teratogenic, immunotoxic,nephrotoxic and carcinogenic effects. Due to the potential harmful effects on human and animal health, OTA has also beenreceiving increased attention globally; however, there is limited information on the presence of OTA in milk and dairy products. The aim of this study was to determine how mycotoxins impact the hygienic quality of raw and heat-processed milk.Materials, Methods & Results: In this study, a total of 105 milk samples were analyzed (35 raw, 35 pasteurized and 35UHT) to identify AFM1 and OTA in raw, pasteurized and ultra-high temperature processing (UHT) milk. The levels ofAFM1 were detected by using the enzyme-linked immunosorbent assay (ELISA). The milk samples were centrifuged inorder to remove the fat content from the milk. After centrifugation, the upper cream layer was withdrawn with a pipette.The non-fat liquid portion was placed in wells at 100 μL for analysis. The concentration of AFM1 in the milk sampleswas analyzed by AFM1 test kit. The milk samples with AFM1 levels greater than 50 ng/L were confirmed by using HighPerformance Liquid Chromatography (HPLC). An Ochratoxin A Serum / Milk ELISA test kit was used for the analysesof OTA. The analyses were made according to the manufacturer’s instructions, and samples were analyzed in duplicate.The absorbance value of milk samples was obtained from the ELISA plate reader at 450 nm...


Assuntos
Aflatoxina M1/isolamento & purificação , Leite/microbiologia , Ocratoxinas/isolamento & purificação , Micotoxinas/análise
16.
Acta sci. vet. (Online) ; 47: Pub. 1626, 2019. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-738817

Resumo

Background: Mycotoxins produced by yeast and fungi have toxic effects on human and animal health. Aflatoxin B1 (AFB1)is the most toxic hepatocarcinogen to mammals. Aflatoxin M1 (AFM1), which has been found in milk and dairy products,is the hydroxylated metabolite of AFB1. Aflatoxin M1 is formed by the cytochrome P450 enzyme in the liver. OchratoxinA (OTA) is synthesized by Aspergillus and Penicillium species. Ochratoxin A is known to cause teratogenic, immunotoxic,nephrotoxic and carcinogenic effects. Due to the potential harmful effects on human and animal health, OTA has also beenreceiving increased attention globally; however, there is limited information on the presence of OTA in milk and dairy products. The aim of this study was to determine how mycotoxins impact the hygienic quality of raw and heat-processed milk.Materials, Methods & Results: In this study, a total of 105 milk samples were analyzed (35 raw, 35 pasteurized and 35UHT) to identify AFM1 and OTA in raw, pasteurized and ultra-high temperature processing (UHT) milk. The levels ofAFM1 were detected by using the enzyme-linked immunosorbent assay (ELISA). The milk samples were centrifuged inorder to remove the fat content from the milk. After centrifugation, the upper cream layer was withdrawn with a pipette.The non-fat liquid portion was placed in wells at 100 μL for analysis. The concentration of AFM1 in the milk sampleswas analyzed by AFM1 test kit. The milk samples with AFM1 levels greater than 50 ng/L were confirmed by using HighPerformance Liquid Chromatography (HPLC). An Ochratoxin A Serum / Milk ELISA test kit was used for the analysesof OTA. The analyses were made according to the manufacturers instructions, and samples were analyzed in duplicate.The absorbance value of milk samples was obtained from the ELISA plate reader at 450 nm...(AU)


Assuntos
Aflatoxina M1/isolamento & purificação , Ocratoxinas/isolamento & purificação , Leite/microbiologia , Micotoxinas/análise
17.
Ci. Rural ; 49(10): e20190428, 2019. graf, tab
Artigo em Inglês | VETINDEX | ID: vti-23945

Resumo

Baccharis alnifolia Meyen & Walp. is a native and medicinal, Chilean Altiplano herb that is used as a poultice and also consumed as an infusion to relieve inflammation. This study evaluated the antioxidant and cytotoxic effect of the ethanolic extract of B. alnifolia and their infusion. It was reported that the ethanol extract contains 4.42 mg GAE/g of dry weight and the infusion contains 35.86 mg GAE/L of total polyphenols. Also, it determined the antioxidant capacity using Ferric reducing antioxidant power (FRAP), Oxygen Radical Absorbance Capacity (ORAC) and Trolox equivalent antioxidant capacity (TEAC) assay. Moreover, seven metabolites including between phenolic acids and flavonoids were identified for the first time in both extracts of the medicinal plant Baccharis alnifolia. The UHPLC-DAD chromatograms revealed the majority presence of ferulic acid and luteolin, both could be responsible for the antioxidant and cytotoxic activity. Furthermore, we realized a preliminary screening of cytotoxicity in different tumor cell lines, finding that these extracts have cytotoxic potential on kidney cells.(AU)


Baccharis alnifolia Meyen & Walp. é uma erva altiplana nativa e medicinal, chilena que é usada como cataplasma e também consumida como uma infusão para aliviar a inflamação. Este estudo avaliou o efeito antioxidante e citotóxico do extrato etanólico de B. alnifolia e sua infusão. Verificou-se que o extrato etanólico contém 4,42 mg GAE / g de peso seco e a infusão contém 35,86 mg GAE / L de polifenóis totais. Além disso, determinou a capacidade antioxidante utilizando o poder antioxidante redutor de Fração (FRAP), Capacidade de Absorção Radical de Oxigênio (ORAC) e capacidade antioxidante equivalente de Trolox (TEAC). Além disso, sete metabólitos, entre ácidos fenólicos e flavonóides, foram identificados pela primeira vez em ambos os extratos da planta medicinal Baccharis alnifolia. Os cromatogramas UHPLC-DAD revelaram a presença majoritária de ácido ferúlico e luteolina, ambos podendo ser responsáveis pela atividade antioxidante e citotóxica. Além disso, realizamos uma triagem preliminar da citotoxicidade em diferentes linhagens de células tumorais, descobrindo que esses extratos têm potencial citotóxico nas células renais.(AU)


Assuntos
Baccharis/química , Plantas Medicinais/química , Antioxidantes/análise , Citotoxinas/análise , Chile
18.
Ciênc. Anim. (Impr.) ; 29(1,supl.1): 25-29, 2019. graf
Artigo em Português | VETINDEX | ID: biblio-1472473

Resumo

O objetivo deste trabalho foi desenvolver um modelo preditivo através de técnica multivariada para diferenciar meios de cultivo de células-tronco cultivadas in vitro e criopreservadas de acordo com os perfis de absorbância obtidas por NIR. Para tanto, foram coletados meios de cultivo de células-tronco oriundo do fluido amniótico de fetos caprinos, antes e após o processo de criopreservação por vitrificarão, e submetidos à análise pelo NIR. Foi possível estimar com alta acurácia o tratamento empregado nas amostras, gerando uma impressão digital dos meios de cultivo in vitro de células criopreservadas ou não.


The objective of this work was to develop a predictive model through a multivariate technique to differentiate culture media from stem cells cultured in vitro and cryopreserved according to the absorbance profiles obtained by NIR. For this purpose, culture media were collected from stem cells from the amniotic fluid of goat fetuses, before and after cryopreservation by vitrification, and submitted to NIR analysis. It was possible to estimate with high accuracy the treatment used in the samples, generating a fingerprint of in vitro culture media of cryopreserved cells or not.


Assuntos
Feminino , Animais , Células-Tronco/fisiologia , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Espectroscopia de Luz Próxima ao Infravermelho/veterinária , Líquido Amniótico , Ruminantes , Técnicas In Vitro/métodos , Técnicas In Vitro/veterinária
19.
Ciênc. Anim. (Impr.) ; 29(1,supl.1): 25-29, 2019. graf
Artigo em Português | VETINDEX | ID: vti-19973

Resumo

O objetivo deste trabalho foi desenvolver um modelo preditivo através de técnica multivariada para diferenciar meios de cultivo de células-tronco cultivadas in vitro e criopreservadas de acordo com os perfis de absorbância obtidas por NIR. Para tanto, foram coletados meios de cultivo de células-tronco oriundo do fluido amniótico de fetos caprinos, antes e após o processo de criopreservação por vitrificarão, e submetidos à análise pelo NIR. Foi possível estimar com alta acurácia o tratamento empregado nas amostras, gerando uma impressão digital dos meios de cultivo in vitro de células criopreservadas ou não.(AU)


The objective of this work was to develop a predictive model through a multivariate technique to differentiate culture media from stem cells cultured in vitro and cryopreserved according to the absorbance profiles obtained by NIR. For this purpose, culture media were collected from stem cells from the amniotic fluid of goat fetuses, before and after cryopreservation by vitrification, and submitted to NIR analysis. It was possible to estimate with high accuracy the treatment used in the samples, generating a fingerprint of in vitro culture media of cryopreserved cells or not.(AU)


Assuntos
Animais , Feminino , Ruminantes , Líquido Amniótico , Espectroscopia de Luz Próxima ao Infravermelho/veterinária , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Técnicas In Vitro/veterinária , Técnicas In Vitro/métodos , Células-Tronco/fisiologia
20.
Semina Ci. agr. ; 40(5): 2071-2078, set.-out. 2019. mapas, tab, graf
Artigo em Inglês | VETINDEX | ID: vti-21883

Resumo

Dekkera bruxellensis is one of the most important contaminant yeasts of alcoholic fermentation. The use of propolis, which can selectively target contaminating yeasts without affecting the starter one, Saccharomyces cerevisiae, could be a useful nonconventional strategy for controlling the growth of contaminant yeasts. The objective of this research was to evaluate four samples of propolis produced by Apis mellifera honeybees from different regions of Argentina as antimicrobial agents against the growth of D. bruxellensis and S. cerevisiae. Hydroalcoholic extracts of propolis were prepared with ethanol:water (70:30 v/v), and the specific absorbance and final concentration of the samples were evaluated. A qualitative in vitro assay in solid medium was performed with different propolis concentrations, and the evaluation of yeast growth was based on a qualitative scale. A quantitative in vitro assay in liquid medium was also performed to assess the yeast cell number, using two different propolis concentrations. The cell number of D. bruxellensis decreased 1.52 and 1.85 log cycles with the two propolis extracts utilised at a concentration of 4.5 mg mL-1 while the cell number of S. cerevisiae decreased 0.48 and 0.76 log cycles with the same samples of propolis. The results from both assays demonstrated the selectivity of propolis use on the yeast species, leading to a higher inhibition of D. bruxellensis growth. This indicates a good potential for using propolis at the concentration of 4.5 mg mL-1, as a nonconventional strategy to control the growth of D. bruxellensis without significantly affecting S. cerevisiae, the yeast starter of ethanol fermentation.(AU)


Dekkera bruxellensis é uma das mais importantes leveduras contaminantes da fermentação alcoólica. O uso de própolis, que pode seletivamente afetar a levedura contaminante mas não a levedura do processo, Saccharomyces cerevisiae, pode ser uma estratégia não convencional útil para o controle de leveduras contaminantes. O objetivo deste trabalho foi avaliar quatro amostras de própolis produzidas por Apis mellifera de diferentes regiões da Argentina como agentes antimicrobianos no controle do crescimento de D. bruxellensis e S. cerevisiae. Foram preparados extratos hidroalcoólicos de própolis com etanol: água (70:30 v/v) e avaliadas a absorbância específica e concentração final das amostras. Um ensaio qualitativo in vitro foi realizado em meio sólido com diferentes concentrações de própolis e a avaliação do crescimento da levedura foi baseada em uma escala qualitativa. Um ensaio quantitativo in vitro em meio líquido foi realizado com duas concentrações de própolis, avaliando-se o número de leveduras. O número de células de D. bruxellensis diminuiu 1,52 e 1,85 ciclos log com dois extratos de própolis na concentração de 4,5 mg mL-1 enquanto para S. cerevisiae, a diminuição no número de células foi de 0,48 e 0,76 ciclos log com as mesmas amostras de própolis. Os resultados de ambos os ensaios demonstraram claramente a seletividade do efeito do emprego de própolis nas leveduras estudadas, resultando em maior inibição no crescimento da levedura D. bruxellensis. Isso indica a boa perspectiva do uso de própolis, na concentração de 4,5 mg mL-1, como uma estratégia não convencional para controlar o crescimento de D. bruxellensis sem afetar substancialmente S. cerevisiae, a levedura agente da fermentação etanólica.(AU)


Assuntos
Própole , Anti-Infecciosos/análise , Dekkera/efeitos dos fármacos , Saccharomyces cerevisiae/efeitos dos fármacos , 26016 , Leveduras/efeitos dos fármacos , Fermentação/efeitos dos fármacos
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