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1.
Biochem Biophys Rep ; 26: 100992, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33898765

RESUMO

This study aimed to assess the effect of supplementation with omega-3 in Wistar rats exposed to ionizing radiation in a dose of 18 Gy on the cortical electrical activity, using mathematical methods such as the power spectrum (PS) and the detrended fluctuation analysis (DFA) in the evaluation of the electrocorticogram (ECoG) record. The PS analysis showed that in non-irradiated animals but supplemented with omega-3 there was a decrease in the power of the beta rhythm, while the DFA applied to different frequency ranges of the ECoG showed a significant increase in the long-range correlation only for the theta wave when compared with non-supplemented animals. In the evaluation of the radiation effect through the PS, an increase in the power of the theta rhythm was observed in both groups (non-supplemented and supplemented animals) only when they were evaluated one week after irradiation. The DFA method also showed difference in this wave. The PS and DFA methods applied to the ECoG record allowed a quantitative analysis of the cortical electrical activity in rats in response to the omega-3 effects, ionizing radiation, or both.

2.
Braz J Med Biol Res ; 53(8): e9268, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32578717

RESUMO

Leptospirosis is a zoonotic disease caused by bacteria of the genus Leptospira, which can cause lipid changes in the erythrocyte membrane. Optical tweezers were used to characterize rheological changes in erythrocytes from patients with leptospirosis in the late stage. Biochemical methods were also used for quantification of plasma lipid, erythrocyte membrane lipid, and evaluation of liver function. Our data showed that the mean elastic constant of erythrocytes from patients with leptospirosis was around 67% higher than the control (healthy individuals), indicating that patient's erythrocytes were less elastic. In individuals with leptospirosis, several alterations in relation to control were observed in the plasma lipids, however, in the erythrocyte membrane, only phosphatidylcholine showed a significant difference compared to control, increasing around 41%. With respect to the evaluation of liver function of individuals with leptospirosis, there was a significant increase in levels of alanine transaminase (154%) and aspartate transaminase (150%), whereas albumin was 43.8% lower than control (P<0.01). The lecithin-cholesterol acyltransferase fractional activity was 3.6 times lower in individuals with leptospirosis than in the healthy individuals (P<0.01). The decrease of the erythrocyte elasticity may be related to the changes of erythrocyte membrane phospholipids composition caused by disturbances that occur during human leptospirosis, with phosphatidylcholine being a strong candidate in the erythrocyte rheological changes.


Assuntos
Eritrócitos , Leptospirose , Membrana Eritrocítica , Humanos , Lipídeos de Membrana , Fosfolipídeos
3.
Braz. j. med. biol. res ; 53(8): e9268, 2020. tab, graf
Artigo em Inglês | LILACS, Coleciona SUS | ID: biblio-1132539

RESUMO

Leptospirosis is a zoonotic disease caused by bacteria of the genus Leptospira, which can cause lipid changes in the erythrocyte membrane. Optical tweezers were used to characterize rheological changes in erythrocytes from patients with leptospirosis in the late stage. Biochemical methods were also used for quantification of plasma lipid, erythrocyte membrane lipid, and evaluation of liver function. Our data showed that the mean elastic constant of erythrocytes from patients with leptospirosis was around 67% higher than the control (healthy individuals), indicating that patient's erythrocytes were less elastic. In individuals with leptospirosis, several alterations in relation to control were observed in the plasma lipids, however, in the erythrocyte membrane, only phosphatidylcholine showed a significant difference compared to control, increasing around 41%. With respect to the evaluation of liver function of individuals with leptospirosis, there was a significant increase in levels of alanine transaminase (154%) and aspartate transaminase (150%), whereas albumin was 43.8% lower than control (P<0.01). The lecithin-cholesterol acyltransferase fractional activity was 3.6 times lower in individuals with leptospirosis than in the healthy individuals (P<0.01). The decrease of the erythrocyte elasticity may be related to the changes of erythrocyte membrane phospholipids composition caused by disturbances that occur during human leptospirosis, with phosphatidylcholine being a strong candidate in the erythrocyte rheological changes.


Assuntos
Humanos , Eritrócitos , Leptospirose , Fosfolipídeos , Membrana Eritrocítica , Lipídeos de Membrana
4.
Braz. j. med. biol. res ; 51(2): e6657, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-889026

RESUMO

Surfactants are amphipathic compounds containing both hydrophilic and hydrophobic groups, capable to lower the surface or interfacial tension. Considering the advantages of the use of biosurfactants produced by microorganisms, the aim of this paper was to develop and characterize a biosurfactant produced by Streptomyces sp. DPUA1559 isolated from lichens of the Amazon region. The microorganism was cultured in a mineral medium containing 1% residual frying soybean oil as the carbon source. The kinetics of biosurfactant production was accompanied by reducing the surface tension of the culture medium from 60 to values around 27.14 mN/m, and by the emulsification index, which showed the efficiency of the biosurfactant as an emulsifier of hydrophobic compounds. The yield of the isolated biosurfactant was 1.74 g/L, in addition to the excellent capability of reducing the surface tension (25.34 mN/m), as observed from the central composite rotational design when the biosurfactant was produced at pH 8.5 at 28°C. The critical micelle concentration of the biosurfactant was determined as 0.01 g/mL. The biosurfactant showed thermal and pH stability regarding the surface tension reduction, and tolerance under high salt concentrations. The isolated biosurfactant showed no toxicity to the micro-crustacean Artemia salina, and to the seeds of lettuce (Lactuca sativa L.) and cabbage (Brassica oleracea L.). The biochemistry characterization of the biosurfactant showed a single protein band, an acid character and a molecular weight around 14.3 kDa, suggesting its glycoproteic nature. The results are promising for the industrial application of this new biosurfactant.


Assuntos
Streptomyces/metabolismo , Tensoativos/metabolismo , Líquens/microbiologia , Valores de Referência , Sementes/efeitos dos fármacos , Temperatura , Fatores de Tempo , Óleo de Soja/química , Contagem de Colônia Microbiana , Análise de Variância , Espectroscopia de Infravermelho com Transformada de Fourier , Meios de Cultura , Eletroforese em Gel de Poliacrilamida , Fermentação , Concentração de Íons de Hidrogênio
5.
Braz J Med Biol Res ; 51(2): e6657, 2017 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-29267499

RESUMO

Surfactants are amphipathic compounds containing both hydrophilic and hydrophobic groups, capable to lower the surface or interfacial tension. Considering the advantages of the use of biosurfactants produced by microorganisms, the aim of this paper was to develop and characterize a biosurfactant produced by Streptomyces sp. DPUA1559 isolated from lichens of the Amazon region. The microorganism was cultured in a mineral medium containing 1% residual frying soybean oil as the carbon source. The kinetics of biosurfactant production was accompanied by reducing the surface tension of the culture medium from 60 to values around 27.14 mN/m, and by the emulsification index, which showed the efficiency of the biosurfactant as an emulsifier of hydrophobic compounds. The yield of the isolated biosurfactant was 1.74 g/L, in addition to the excellent capability of reducing the surface tension (25.34 mN/m), as observed from the central composite rotational design when the biosurfactant was produced at pH 8.5 at 28°C. The critical micelle concentration of the biosurfactant was determined as 0.01 g/mL. The biosurfactant showed thermal and pH stability regarding the surface tension reduction, and tolerance under high salt concentrations. The isolated biosurfactant showed no toxicity to the micro-crustacean Artemia salina, and to the seeds of lettuce (Lactuca sativa L.) and cabbage (Brassica oleracea L.). The biochemistry characterization of the biosurfactant showed a single protein band, an acid character and a molecular weight around 14.3 kDa, suggesting its glycoproteic nature. The results are promising for the industrial application of this new biosurfactant.


Assuntos
Líquens/microbiologia , Streptomyces/metabolismo , Tensoativos/metabolismo , Análise de Variância , Contagem de Colônia Microbiana , Meios de Cultura , Eletroforese em Gel de Poliacrilamida , Fermentação , Concentração de Íons de Hidrogênio , Valores de Referência , Sementes/efeitos dos fármacos , Óleo de Soja/química , Espectroscopia de Infravermelho com Transformada de Fourier , Streptomyces/crescimento & desenvolvimento , Streptomyces/isolamento & purificação , Tensão Superficial , Tensoativos/análise , Tensoativos/química , Temperatura , Fatores de Tempo
6.
Neotrop Entomol ; 46(2): 223-230, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27844468

RESUMO

In order to find new alternatives for vector control and personal protection, we evaluated the larvicidal and repellent activity of essentials oils from plants found in the Northeast of Brazil against Aedes aegypti Linnaeus mosquitoes. The plants tested include Xylopia laevigata, Xylopia frutescens, and Lippia pedunculosa and their major compounds, piperitenone oxide, and (R)-limonene. The essential oil of L. pedunculosa and its major volatile compounds were shown to be toxic for Ae. aegypti larvae with a LC50 lower than 60 ppm. The essential oil of plants from the Xylopia genus, on the other hand, showed no activity against Ae. aegypti, proving to be toxic to mosquito larvae only when concentrations were higher than 1000 ppm. All plants tested provided some degree of protection against mosquitoes landing, but only the essential oil of L. pedunculosa and the volatile compound piperitenone oxide suppressed 100% of mosquitoes landing on human skin, in concentrations lower than 1%. Among the plants studied, the essential oil of L. pedunculosa and its volatiles compounds have shown the potential for the development of safe alternative for mosquito larvae control and protection against Ae. aegypti mosquito bites.


Assuntos
Aedes , Inseticidas/toxicidade , Óleos Voláteis/toxicidade , Animais , Brasil , Humanos , Larva , Lippia , Controle de Mosquitos , Xylopia
7.
Genet Mol Res ; 14(2): 6303-11, 2015 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-26125833

RESUMO

Knowledge of dominance effects should improve ge-netic evaluations, provide the accurate selection of purebred animals, and enable better breeding strategies, including the exploitation of het-erosis in crossbreeds. In this study, we combined genomic and pedi-gree data to study the relative importance of additive and dominance genetic variation in growth and carcass traits in an F2 pig population. Two GBLUP models were used, a model without a polygenic effect (ADM) and a model with a polygenic effect (ADMP). Additive effects played a greater role in the control of growth and carcass traits than did dominance effects. However, dominance effects were important for all traits, particularly in backfat thickness. The narrow-sense and broad-sense heritability estimates for growth (0.06 to 0.42, and 0.10 to 0.51, respectively) and carcass traits (0.07 to 0.37, and 0.10 to 0.76, respec-tively) exhibited a wide variation. The inclusion of a polygenic effect in the ADMP model changed the broad-sense heritability estimates only for birth weight and weight at 21 days of age.


Assuntos
Peso ao Nascer/genética , Genômica , Herança Multifatorial/genética , Suínos/genética , Animais , Cruzamento , Variação Genética , Carne , Linhagem , Suínos/crescimento & desenvolvimento
8.
Reprod Domest Anim ; 50(4): 545-53, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25865710

RESUMO

This study aimed to assess the effects of different cooling curves and centrifugation regimes used in cryopreservation protocols on the post-thaw viability of Piau-breed wild boar (Sus scrofa) sperm using in vitro assessment tests. Two centrifugations (800 g for 10 min and 2400 g for 3 min) and two cooling curves (conventional cooling using nitrogen vapour - freezing 1 and automated cooling using a programmed freezing machine - freezing 2) were tested. Therefore, the treatments were divided into M3 - centrifugation at 2400 g for 3 min and freezing 2; M10 - centrifugation at 800 g for 10 min and freezing 2; R3 - centrifugation at 2400 g for 3 min and freezing 1; and R10 - centrifugation at 800 g for 10 min and freezing 1. No significant differences (p > 0.05) between treatments occurred post-thawing regarding the total sperm motility means recorded. The mean values of the different treatments were not different from each other regarding the supravital staining (SV), hypo-osmotic test (HO), sperm-egg binding assay or sperm morphology. This study showed that both the cooling curve and the centrifugation regime affected the quality of post-thaw sperm, and centrifugation for shorter times and cooling curves using automated cooling are the most suitable for minimizing sperm injury.


Assuntos
Centrifugação/métodos , Criopreservação/veterinária , Preservação do Sêmen/veterinária , Sus scrofa , Acrossomo/ultraestrutura , Animais , Membrana Celular/ultraestrutura , Sobrevivência Celular , Criopreservação/métodos , Congelamento , Temperatura Alta , Masculino , Nitrogênio , Preservação do Sêmen/métodos , Motilidade dos Espermatozoides , Interações Espermatozoide-Óvulo , Espermatozoides/anormalidades , Espermatozoides/fisiologia , Espermatozoides/ultraestrutura , Fatores de Tempo
9.
Arq. bras. med. vet. zootec ; 66(4): 1003-1009, 08/2014. tab, graf
Artigo em Português | LILACS | ID: lil-722551

RESUMO

O objetivo deste trabalho foi observar a influência do campo magnético (CM) de baixa frequência na membrana do saco vitelínico (MSV) e no desenvolvimento do embrião de codornas japonesas (Coturnix japonica) em 72 horas de incubação. Ovos fertilizados foram expostos a nove horas consecutivas de CM, sendo um grupo a partir das 48 horas e o outro a partir das 63 horas de incubação. A quantificação da vascularização da MSV foi determinada pela obtenção da dimensão fractal por meio dos métodos de box-counting e de dimensão de informação, enquanto o peso corporal e o percentual de comprimento cefálico dos embriões foram utilizados como parâmetros de desenvolvimento embrionário. O CM não causou diferenças significativas na densidade vascular da MSV nem no desenvolvimento embrionário, quando comparados ao grupo controle...


The aim of this study was to observe the influence of the low frequency magnetic field (MF) on the yolk sac membrane (YSM) and embryonic development of Japanese quail (Coturnix japonica) in 72 hours of incubation. Fertilized eggs were exposed to 9 consecutive hours of MF, with a group from 48 hours and the second group from 63 hours of incubation. The evaluation of YSM vascularization was determined by the fractal dimensions obtained through box-counting method and information dimension, while body weight of the embryo and percentage of cephalic length were used as parameters for embryo development. The MF caused no significant differences in vessel density in the YSM, nor in the embryonic development considering the body weight and percentage cephalic length, when were compared to the control group...


Assuntos
Animais , Coturnix/embriologia , Desenvolvimento Embrionário , Campos Magnéticos , Saco Vitelino/crescimento & desenvolvimento , Membrana Vitelina/crescimento & desenvolvimento
10.
Arq. bras. med. vet. zootec ; 66(4): 1003-1009, 08/2014. tab, graf
Artigo em Português | VETINDEX | ID: vti-11120

RESUMO

O objetivo deste trabalho foi observar a influência do campo magnético (CM) de baixa frequência na membrana do saco vitelínico (MSV) e no desenvolvimento do embrião de codornas japonesas (Coturnix japonica) em 72 horas de incubação. Ovos fertilizados foram expostos a nove horas consecutivas de CM, sendo um grupo a partir das 48 horas e o outro a partir das 63 horas de incubação. A quantificação da vascularização da MSV foi determinada pela obtenção da dimensão fractal por meio dos métodos de box-counting e de dimensão de informação, enquanto o peso corporal e o percentual de comprimento cefálico dos embriões foram utilizados como parâmetros de desenvolvimento embrionário. O CM não causou diferenças significativas na densidade vascular da MSV nem no desenvolvimento embrionário, quando comparados ao grupo controle.(AU)


The aim of this study was to observe the influence of the low frequency magnetic field (MF) on the yolk sac membrane (YSM) and embryonic development of Japanese quail (Coturnix japonica) in 72 hours of incubation. Fertilized eggs were exposed to 9 consecutive hours of MF, with a group from 48 hours and the second group from 63 hours of incubation. The evaluation of YSM vascularization was determined by the fractal dimensions obtained through box-counting method and information dimension, while body weight of the embryo and percentage of cephalic length were used as parameters for embryo development. The MF caused no significant differences in vessel density in the YSM, nor in the embryonic development considering the body weight and percentage cephalic length, when were compared to the control group.(AU)


Assuntos
Animais , Coturnix/embriologia , Campos Magnéticos , Saco Vitelino/crescimento & desenvolvimento , Desenvolvimento Embrionário , Membrana Vitelina/crescimento & desenvolvimento
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