RESUMO
Male and female Syrian hamsters were used to investigate the influence of two husbandry systems on their physiological aspects. The hypothesis is that there may be physiological, behavioral and final results differences in a litter that is managed in different housing systems (open cage or micro isolator). For the present study, 5 male and 5 female hamsters were kept separately in open cages and 5 male hamsters and 5 females separately in micro isolators from the age of 28 to reproductive age (60 days). Animal management was controlled by monitoring the supply and consumption of water, feed and environmental enrichment provided, with the micro isolator group receiving sterilized water and management carried out exclusively at a changing station. To evaluate metabolic changes caused by water supply, urine tests were carried out on dipstick in sample pools. After reaching reproductive age, ten couples were formed, 5 of them in micro isolators and the other 5 in open cages, uniting a male with a female from the same experimental group to evaluate reproductive data. The animals were weighed until the week of the females' birth, followed by counting and sexing the puppies for data analysis. The groups demonstrated through growth curves that the environment in which the animals are housed has an influence on the animal's physiology. The study showed differences in weight gain in addition to a lower rate of stress in the female, resulting in less aggression towards the male after mating. of couples when comparing the two experimental groups. It also showed a difference in the number of puppies per female between the groups. In addition to providing evidence that housing conditions can influence the hamster's physiology, there is evidence that it also influences the animals' aggressive behavior. This study aims to assist peers in breeding the species in breeding and experimental animal facilities, in addition to ensuring confidence in the reproducibility of future studies, since there is currently not enough information for the correct management of the biomodel.
Hamsters sírios machos e fêmeas foram utilizados para investigar a influência de dois sistemas de criação sob seus aspectos fisiológicos. A hipótese é que pode haver diferenças fisiológicas, comportamentais e no resultado final de uma ninhada a qual é manejada em sistemas diferentes de alojamento (gaiola aberta ou micro isolador). Para o presente estudo foram mantidos 5 hamsters machos e 5 fêmeas separadamente em gaiolas abertas e 5 exemplares machos e mais 5 fêmeas separadamente em micro isoladores na idade de 28 até a idade reprodutiva, (60 dias). O manejo dos animais foi controlado acompanhando a oferta e consumo de água, ração e enriquecimento ambiental fornecidos, sendo que o grupo de micro isolador recebeu água esterilizada e seu manejo feito exclusivamente em estação de troca. Para avaliação de alteração metabólica pelo fornecimento de água foram realizados testes de urina em fita reagente em pools de amostra. Após atingirem a idade reprodutiva foram formados dez casais, sendo 5 deles de micro isolador e os outros 5 de gaiolas abertas, unindo um macho com uma fêmea do mesmo grupo experimental para avaliação de dados reprodutivos. A pesagem dos animais foi feita até a semana de parto das fêmeas, seguindo com a contagem e sexagem dos filhotes para análise dos dados. Os grupos demonstraram por meio das curvas de crescimento que o meio em que os animais são alojados tem influência na fisiologia do animal, o estudo apontou diferenças no ganho de peso além de menor taxa de estresse da fêmea resultando em menor agressão ao macho após a união dos casais quando comparados os dois grupos experimentais. Apontou diferença também, no número de filhotes por fêmeas entre os grupos. Além de fornecer evidências de que as condições de alojamento podem influenciar na fisiologia do hamster há indícios de que também há influência no comportamento de agressividade dos animais. Este estudo visa auxiliar os pares na criação da espécie em biotérios de criação e experimentação, além de garantir confiança na reprodutibilidade de futuros estudos, uma vez que atualmente não existem informações o suficiente para o manejo correto do biomodelo.
RESUMO
Andes virus, an orthohantavirus endemic to South America, causes severe hantavirus cardiopulmonary syndrome associated with human-to-human transmission. No approved treatments or vaccines against this virus are available. We show that a combined treatment with 2 monoclonal antibodies protected Syrian hamsters when administered at midstage or late-stage disease.
Assuntos
Infecções por Hantavirus , Orthohantavírus , Animais , Anticorpos Monoclonais/uso terapêutico , Cricetinae , Infecções por Hantavirus/tratamento farmacológico , Humanos , Mesocricetus , América do SulRESUMO
Leptospirosis is a world-wide zoonotic disease caused by pathogenic Leptospira and can be asymptomatic or can cause clinical signs ranging from influenza-like to multi-organ failure and death in severe cases. While species and strain specificity can play a major role in disease presentation, the hamster is susceptible to most leptospiral infections and is the model of choice for vaccine efficacy testing. During evaluation of blood smears from hamsters challenged with different species and strains of Leptospira, a circulating population of large, mononuclear, lipid-filled cells, most similar to foamy macrophages (FMs), was detected. Circulating FMs were identified by Giemsa staining and verified by scanning and transmission electron microscopy. FMs were found in the circulating blood of all Leptospira-challenged hamsters, indicating that the finding was not species or strain specific, although higher numbers of FMs tended to correlate with severity of disease. The unique finding of circulating FMs in the hamster model of leptospirosis can yield additional insights into the pathogenesis of leptospirosis and other diseases that induce circulating FMs.
RESUMO
SummaryThe Deleted in AZoospermia (DAZ) gene family regulates the development, maturation and maintenance of germ cells and spermatogenesis in mammals. The DAZ family consists of two autosomal genes, Boule and Dazl (Daz-like), and the Daz gene on chromosome Y. The aim of this study was to analyze the localization of DAZL and BOULE during testicular ontogeny of the seasonal-breeding Syrian hamster, Mesocricetus auratus. We also evaluated the testicular expression of DAZ family genes under short- or long-photoperiod conditions. In the pre-pubertal and adult testis, DAZL protein was found mainly in spermatogonia. BOULE was found in the spermatogonia from 20 days of age and during the pre-pubertal and adult period it was also detected in spermatocytes and round spermatids. DAZL and BOULE expression in spermatogonia was strictly nuclear only in 20-day-old hamsters. We also detected the novel mRNA and protein expression of BOULE in Leydig cells. In adult hamsters, Dazl expression was increased in regressed testis compared with non-regressed testis and DAZL protein expression was restricted to primary spermatocytes in regressed testis. These results show that DAZL and BOULE are expressed in spermatogonia at early stages in the Syrian hamster, then both proteins translocate to the cytoplasm when meiosis starts. In the adult regressed testis, the absence of DAZL in spermatogonia might be related to the decrease in germ cell number, suggesting that DAZ gene family expression is involved in changes in seminiferous epithelium during photoregression.
Assuntos
Fotoperíodo , Proteínas de Ligação a RNA/genética , Testículo/fisiologia , Fatores Etários , Animais , Regulação da Expressão Gênica , Células Intersticiais do Testículo/metabolismo , Masculino , Mesocricetus , Proteínas de Ligação a RNA/metabolismo , Espermatócitos/metabolismo , Espermatogônias/metabolismo , Testículo/citologiaRESUMO
Objetivo. El objetivo de este trabajo fue caracterizar en el biomodelo Mesocricetus auratus la sintomatología y lesiones anatomopatológicas que provocan 5 aislados clínicos de Leptospira spp., provenientes de Nicaragua. Materiales y métodos. Con este fin se inocularon 50 hámster por vía i.p con 1mL del cultivo de cada una de las cepas en fase exponencial teniendo una concentración celular de 7.5 x 106 leptospira/mL (10 animales por cepa), evaluándose signos de la enfermedad, mortalidad durante 14 días, lesiones anatomopatológicas macroscópicas y microscópicas mediante tinción con hematoxilina-eosina y tinción de Warthyn Starryn. Resultados. Todas las cepas presentaron alta mortalidad, mostrando un cuadro tanto clínico, como lesional característico de la infección experimental. Además, causaron la muerte al 100% de los animales entre el tercer y décimo día postinfección. En el estudio anatomopatológico la cepa del serogrupo Ballum y la del serogrupo Pomona produjeron focos de hemorragias específicamente en el riñón y pulmones. De forma similar ocurrió una congestión hepática y renal, mientras que la hemorragia renal fue observada con mayor frecuencia en la cepa del serogrupo Pomona, diferenciándose del resto de las cepas que mostraron esta lesión con menos frecuencia. Conclusiones. Este trabajo permitió una mayor caracterización de estas cepas siendo utilizadas como futuras candidatas vacunales frente a una nueva epidemia de Leptospirosis en Nicaragua.
Objective. The aim of this study was to characterize the symptomatology and anatomopathological lesions caused by 5 clinical isolated Leptospira spp. from Nicaragua in a Mesocricetus auratus biomodel. Materials and methods. 50 hamsters were inoculated via i.p with 1mL of the culture of each strain in exponential phase having a cellular concentration of 7.5 x 106 leptospira/mL, (10 animals per strain). Signs of the disease, mortality during 14 days, and macroscopic and microscopic anatomopathological lesions by haematoxylin-eosin and Warthyn Starryn stain technique were evaluated. Results. All the strains presented high mortality, showing clinical lesions of the experimental infection. Death to 100% of the animals was caused between the third and tenth day post-infection. In the anatomopathologic study, the strains of the Ballum and Pomona serogroup produced haemorrhaging specifically in the kidney and lungs. The animals manifested hepatic and renal congestion, while the renal haemorrhage was observed with more frequency in the strain of the Pomona serogroup, differing from the other strains, which presented this lesion less frequently. Conclusions. This work allowed a better characterization of these strains in order to use them as future vaccine candidates for future Leptospirosis epidemics in Nicaragua.
Assuntos
Humanos , Animais , Leptospira , Mesocricetus , Sinais e SintomasRESUMO
Flavonoids have been reported to exhibit several pharmacological properties, mainly in cardiovascular and inflammatory diseases. In the present study, we observed that rutin, a known glycosylated flavonoid isolated from Dimorphandra mollis, had a lowering effect on plasma triglyceride levels of diet-induced hypercholesterolemic Golden Syrian hamsters, but did not change total cholesterol and high-density lipoprotein cholesterol levels. Moreover, high-fat or rutin supplemented diets showed no immunotoxic effects, since no significant changes were observed on total white blood cells, granulocytes and mononuclear cells, as well as on the neutrophil apoptosis degree, when compared to untreated animals. Therefore, rutin seems to be a selective and non-toxic modulator of hypercholesterolemia, which can be promising for the development of new drugs.
Os flavonóides possuem diversas propriedades farmacológicas, principalmente nas doenças cardiovasculares e inflamatórias. No presente estudo, observamos que a rutina, um conhecido flavonóide glicosilado isolado da Dimorphandra mollis, diminuiu o nível de triglicerídeos plasmáticos em hamsters Golden Syrian hipercolesterolêmicos sem alterar os níveis de colesterol total e colesterol HDL. Além disso, observamos que dietas hipercolesterolêmicas ou suplementadas com rutina não apresentaram efeito imunotóxico, uma vez que nenhuma alteração significativa foi observada nos leucócitos totais, granulócitos e células mononucleares, bem como no grau de neutrófilos em apoptose, quando comparado com animais não tratados. Portanto, a rutina parece ser um modulador seletivo e não tóxico da hipercolesterolemia, o que pode ser promissor para o desenvolvimento de novos fármacos.