Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Braz J Biol ; 84: e279474, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38747862

RESUMO

Variability in snake venom composition is well-documented and crucial for understanding snake ecology and predicting snakebites. In this study, we characterize the venom composition and biological activities of newborn female and male Bothrops moojeni and their mother. Our results reveal significant differences between the venom of newborn females and males, demonstrating a broad and diverse range of proteins. The venoms of newborn females showed higher serine protease effects, increased hemorrhagic activity, and greater lethality compared to the venom of newborn males. However, no differences were observed in phospholipase A2 and coagulant activity. The differences in protein composition and toxic activities between maternal and neonatal venom, as well as between the venoms of newborn females and males, contribute to understanding the diverse outcomes of snakebites. These results underscore the importance of considering sex and ontogeny in understanding venom composition in snakes.


Assuntos
Animais Recém-Nascidos , Bothrops , Venenos de Crotalídeos , Animais , Bothrops/classificação , Bothrops/fisiologia , Feminino , Masculino , Fatores Sexuais
2.
Braz J Biol ; 82: e264933, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36350940

RESUMO

The objective of this study was to describe the histology and histochemistry of the integument covering the back and stinger of the freshwater stingray Potamotrygon rex, endemic to the Middle Upper Tocantins River. The species has a dark back and yellowish circular spots that extend to the tail, which has one to two stings located in the median portion of the tail. Through histological study it was observed that the epithelia of the back and stinger are composed of non-keratinized stratified pavement epithelial tissue, and are organized in three layers: basal, intermediate and superficial. The differences between the tissues are related to the cell types that compose them. The back is organized with epithelial cells, mucus cells, granulocyte cells and chromatophores. The mucus cells are distributed in different layers along the animal's back, influencing the thickness of the tissue. The tissue that covers the stinger is composed of epithelial cells, chromatophores and specialized cells in protein synthesis. In the histochemistry, the stinger epithelial cells were stained with Bromophenol Blue, especially those of the intermediate layer, which were called specialized cells. In the back the epithelial cells were stained with Bromophenol Blue, Alcian Blue and PAS, and the mucous cells with PAS. In both tissues the presence of protein reserves was detected, areas so called because they are stained strongly with Bromophenol Blue. The results show that the stinger presents activity directed to the production of proteins, and that the back is organized to produce different components, which constitute the cuticle that covers the animal's body.


Assuntos
Mordeduras e Picadas , Rajidae , Animais , Azul de Bromofenol/metabolismo , Água Doce , Rios
3.
Braz J Biol ; 82: e264677, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36287404

RESUMO

Sodium lauryl sulfate is the main cleaning ingredient in shampoos, even though it may be potentially damaging to hair. The demand for antioxidant-rich cosmetics, on the other hand, has encouraged green cosmetics research. Brazil has vast biodiversity that can be exploited for the production of these cosmetics. This work aimed to develop a minimalist antioxidant lauryl-free shampoo formulation with leaf extracts from the Brazilian plant Hancornia speciosa Gomes. Two hydroethanolic extracts were prepared using different extraction methods, Soxhlet, and ultrasound. The extracts were characterized by the presence of saponins, polyphenol quantification, and HLPC chemical identification of the compounds. Antioxidant activity was determined using the DPPH method. The antioxidant lauryl-free shampoo was developed using hydroxyethyl cellulose with two concentrations of leaf extract obtained by Soxhlet, 0.125 mg/g (XP1) and 0.250 mg/g (XP2). Along with the antioxidant activity, the physical and chemical properties, cleaning potential, and foam quality were evaluated. The Soxhlet leaf extract revealed a more favorable chemical profile, including a positive result for saponins, as well as a larger quantity of polyphenols and increased antioxidant activity. The XP2 formulation showed better foam height, dirt dispersion, and antioxidant activity. Thus, the use of mangabeira leaf extract appears to be promising for the development of shampoos with antioxidant activity.


Assuntos
Antioxidantes , Saponinas , Antioxidantes/farmacologia , Antioxidantes/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Polifenóis , Brasil , Dodecilsulfato de Sódio , Celulose , Folhas de Planta
4.
Braz J Biol ; 84: e258041, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35674601

RESUMO

The serpent study involves physiological, behavioral and interaction factors with an extremely dynamic and complex environment. The relation of these animals with biodiversity is still quite preliminary, little studied and sustained by popular practices related to traditional medicine, esoteric and mystical currents. Therefore, this study proposed to know about the effect of 80% crude alcoholic extract of Petiveria alliacea L., popularly known as Tipi Herb, and its effects associated with the repellency of the Bothrops moojeni serpent. A complex of boxes was built for the observation of the snake's displacement, carried out for a total period of six days, the first three for defining the exploratory pattern and the other two for testing the alcoholic extract of Tipi, and finally on the sixth day, one cycle with the presence of a live attractant as bait. It was observed that the animal had no inhibition behavior and moved through the complex in a way like what occurs in nature and showed behavior to avoid remaining in the presence of the extract both with the presence of a live attractant or without it, preferring to move in the other compartments. The results show that this proposed tool is valid for the study of displacement of Bothrops moojeni snakes, in the same way that it added values on the importance of cerrado biome biodiversity and on the popular medicine practices of Tipi Herb, since the repellent effect on the snake was significant in the two tests performed.


Assuntos
Bothrops , Repelentes de Insetos , Animais , Medicina Tradicional , Extratos Vegetais/farmacologia , Serpentes
5.
Brain Res Bull ; 75(5): 629-39, 2008 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-18355639

RESUMO

The present study evaluated four phospholipase A2 (PLA2) (Mlx-8, Mlx-9, Mlx-11 and Mlx-12) isolated from Micrurus lemniscatus snake venom (Elapidae). The effects of intrahippocampal administration of these toxins have been determined on behavior, electroencephalography, and neuronal degeneration in rats. These four PLA2 toxins induced motor and EEG alterations in a dose-dependent manner. Behavioral convulsions were characterized by clonic movements and were often accompanied by EEG alterations. Mlx toxins were convulsive but weakly epileptogenic, since low rates of seizure discharges were observed in EEG records. Neuronal injury seemed to depend on the dose of the toxin used. The highest doses of toxins caused severe intoxication and death of some animals. The injury of hippocampal cells was characterized by massive neuronal loss and hippocampal gliosis. A high occurrence of compulsive scratching was observed. Moreover, the onset of seizures induced by Mlx toxins was markedly delayed. The similarities between the effects of Mlx PLA2s and those isolated from other Elapidae snakes venoms suggest that their toxicity are probably due to their specific binding to neuronal membranes and to the catalysis of phospholipid hydrolysis, producing lysophospholipids and fatty acids. These compounds likely disturb the membrane conformation, causing a marked increase in the release of neurotransmitters and concurrent inhibition of vesicle fission and recycling. These toxins can be a useful tool to investigate properties of endogenous secretory PLA2s and therefore may be important both to study mechanisms involved in neurotransmitter release at nerve terminals and to explain the convulsive properties of PLA2s toxins.


Assuntos
Comportamento Animal/efeitos dos fármacos , Venenos Elapídicos/química , Eletroencefalografia/efeitos dos fármacos , Síndromes Neurotóxicas/etiologia , Fosfolipases A2/análise , Fosfolipases A2/farmacologia , Animais , Cromatografia Líquida de Alta Pressão/métodos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Venenos Elapídicos/classificação , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Hipocampo/fisiopatologia , Masculino , Espectrometria de Massas/métodos , Camundongos , Degeneração Neural/induzido quimicamente , Degeneração Neural/patologia , Síndromes Neurotóxicas/patologia , Ratos
7.
Int J Aging Hum Dev ; 34(3): 175-84, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1582711

RESUMO

Two new issues of pet ownership were considered in a mail questionnaire and an interview survey of a large number of elderly people age sixty and over. First, evidence was obtained that pets are an important determinant of housing choice. Second, many elderly pet owners have made no arrangements for the pet if they predecease it or become unable to care for it. Problems related to these issues are discussed.


Assuntos
Atividades Cotidianas/psicologia , Envelhecimento/psicologia , Atitude Frente a Morte , Vínculo Humano-Animal , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Illinois , Masculino , Meio Social
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...