Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Food Chem Toxicol ; 49(9): 1989-97, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21609751

RESUMO

Virtually ever since it was first commercialized in 1995, there have been several studies focusing on the use of olive leaf extract (OLE) as a natural therapy and its medical properties. The aim of this study was to investigate the effects of three different concentrations of OLE on the function of mice livers over the course of 14 weeks. Female ICR mice were divided into four groups, depending on OLE concentration used: 0%, 0.25%, 0.5%, and 0.75%. Alanine aminotransferase, alkaline phosphatase, total bilirubin and albumin serum concentrations were all measured. Histopathological changes of the liver were observed after haematoxylin and eosin, reticulin, and Masson's trichrome staining was carried out while liver mitochondrial bioenergetics were also evaluated. Alanine aminotransferase and alkaline phosphatase serum enzyme activities increased significantly in the groups in which 0.5% and 0.75% OLE concentrations were used. Histologically, all the groups exposed to OLE exhibited hyperplasia of the bile ducts, cholestasis, hepatocyte necrosis and inflammatory infiltrated. Hepatic fibrosis was observed in the groups featuring 0.5% and 0.75% OLE concentrations. The mitochondrial membrane potential, respiratory control ratio and ADP/O of samples from animals fed the higher OLE concentration was significantly decreased when compared to the control group.


Assuntos
Fígado/efeitos dos fármacos , Olea/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Animais , Relação Dose-Resposta a Droga , Feminino , Camundongos , Camundongos Endogâmicos ICR
2.
Radiat Prot Dosimetry ; 144(1-4): 140-3, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21081520

RESUMO

In this paper, the results aimed at assessing the performance of two varieties of LiF detectors (LiF:Mg,Ti and LiF:Mg,Cu,P) in photon fields relatively to reproducibility, detection threshold and angular dependence as defined in the ISO 12794 standard are presented. The fading properties and the limit of detection were also investigated for both materials. The results suggest that both LiF varieties are well suited for extremity monitoring. However, better fading properties of LiF:Mg,Cu,P when compared with LiF:Mg,Ti, combined with previous results relatively to energy dependence suggests that LiF:Mg,Cu,P dosemeters are better suited for extremity monitoring.


Assuntos
Monitoramento de Radiação/normas , Proteção Radiológica/normas , Radiometria/normas , Algoritmos , Cobre/análise , Fluoretos/análise , Humanos , Compostos de Lítio/análise , Magnésio/análise , Teste de Materiais , Modelos Estatísticos , Fósforo/análise , Doses de Radiação , Monitoramento de Radiação/métodos , Proteção Radiológica/métodos , Radioisótopos/análise , Radiometria/métodos , Reprodutibilidade dos Testes , Titânio/análise
3.
Arq. bras. med. vet. zootec ; 57(4): 465-475, ago. 2005.
Artigo em Português | LILACS | ID: lil-415187

RESUMO

Realizou-se uma análise estereológica comparativa de complexos cumulus-ovócito (COCs) de bovino da raça Holtein-Friesian aspirados de folículos antrais pequenos (com diâmetro de 1-4mm) e médios (com diâmetro de 4-8mm) durante as fases de metaestro, diestro e de proestro. Foram estimados o volume médio dos COCs, dos ovócitos (com e sem zona pelúcida), dos núcleos dos ovócitos e das células foliculares e seus respectivos núcleos. Estimou-se a espessura da zona pelúcida e calculou-se a percentagem relativa da freqüência dos diferentes tipos de células foliculares encontradas no cumulus. Os folículos pequenos apresentaram crescimento acelerado e sem sincronia entre o volume do citoplasma e o do núcleo. No folículo médio ocorreu expansão harmoniosa núcleo-citoplasmática. Identificaram-se três populações de células foliculares (C1, C2 e C3), cuja distribuição na massa do cumulus é independente de sua posição relativamente ao ovócito. Durante o ciclo estral, as células C1 foram progressivamente substituídas por C2 e estas, por C3.


Assuntos
Bovinos , Corpo Lúteo/anatomia & histologia , Folículo Ovariano/anatomia & histologia , Ovário/anatomia & histologia
4.
Tissue Cell ; 35(5): 313-23, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14517099

RESUMO

Stereological methods were applied to bovine cumulus-oocyte complexes (COCs) in order to characterize them quantitatively during the estrous cycle. COCs from medium (4-8mm) antral follicles with a compact and complete cumulus mass, and with an uniform or a non-visible ooplasm were aspirated from ovaries of Holstein-Friesian cows, fixed in glutaraldehyde, randomly embedded in glycol-methacrylate, and sectioned at 20 microm. The unbiased nucleator principle was used for estimating the mean volumes of complexes, oocytes, cumulus cells, and nuclei of oocytes and cumulus cells. The thickness of the zona pellucida and the relative numerical percentages of the several morphological types (C1-C3) of cumulus cells were also evaluated. The optical disector procedure was used for cumulus cell sampling. Quantitative data show that COCs appear heterogeneous for all studied parameters. From metestrus to proestrus the volumes of COCs and oocytes remained constant, the volumes of oocytes and oocyte nuclei were correlated, the thickness of the outer zona pellucida decreased, and the relative numerical frequency of follicular type C3 cells increased. Results suggest that COCs from distinct estrus stages are structurally different, with type C3 follicular cells gradually differentiating from cell types C1 and C2.


Assuntos
Ciclo Estral/fisiologia , Oócitos/ultraestrutura , Folículo Ovariano/ultraestrutura , Animais , Bovinos , Núcleo Celular/ultraestrutura , Feminino , Processamento de Imagem Assistida por Computador , Oócitos/fisiologia , Folículo Ovariano/fisiologia , Zona Pelúcida/fisiologia , Zona Pelúcida/ultraestrutura
5.
Theriogenology ; 60(3): 429-43, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12763157

RESUMO

Bovine cumulus-oocyte complexes (COCs) aspirated from slaughterhouse ovaries are used for in vitro maturation and fertilization after selection on the basis of morphological appearance of the cumulus and ooplasm. In this context, a quantitative characterization of COCs could provide additional criteria for selecting the most competent complexes. Bovine COCs from small (1-4mm) antral follicles were aspirated from metestrous and proestrous stage ovaries of Holstein-Friesian cows, fixed in glutaraldehyde, randomly embedded in glycol-methacrylate, and sectioned at 20 microm. The unbiased nucleator principle of stereology was used for estimating the mean volumes of complexes, oocytes, cumulus cells, and nuclei of oocytes and cumulus cells. The thickness of the zona pellucida and the relative numerical percentages of the several morphological types (C1, C2 and C3) of cumulus cells were also evaluated. The optical dissector procedure was used for cumulus cell sampling. Quantitative data show that the variability among complexes is generally high, especially for the volume of COCs. There were no linear correlations between the studied parameters, except between the volume of the oocyte and nucleus at metestrus. At proestrus, the volumes of COCs, oocytes and nuclei of oocytes, the volume of follicular cells and the thickness of the inner zona pellucida, were significantly higher than at metestrus. The relative numerical frequency of follicular type C1 cells was lower whereas that of type C3 cells was higher at proestrus than at metestrus. In conclusion, small antral follicles had larger COCs and oocytes at proestrus compared to metestrus and the COCs also had a higher percentage of follicular type C3 cells. Results suggest that for the same type of follicle size there may exist different functional populations of COCs at distinct stages of the bovine ovarian cycle.


Assuntos
Bovinos , Metestro , Oócitos/ultraestrutura , Folículo Ovariano/ultraestrutura , Proestro , Animais , Nucléolo Celular/ultraestrutura , Núcleo Celular/ultraestrutura , Tamanho Celular , Citoplasma/ultraestrutura , Feminino , Sucção , Coleta de Tecidos e Órgãos/métodos , Coleta de Tecidos e Órgãos/veterinária , Zona Pelúcida/ultraestrutura
6.
Biol Reprod ; 65(5): 1383-91, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11673254

RESUMO

Bovine ovarian cumulus-oocyte complexes (COCs) are used for in vitro maturation and fertilization after selection by size and morphology, but their developmental potential remains low. Stereology could provide more objective criteria for selecting the most competent complexes, but its application is lacking in cattle. COCs from small (1-4 mm) antral follicles were aspirated from diestrous ovaries of Holstein-Friesian cows, fixed in glutaraldehyde, randomly embedded in glycol-methacrylate, and sectioned at 20 microm. The unbiased nucleator principle was used for estimating the mean volumes of complexes, oocytes, cumulus cells, and nuclei of oocytes and cumulus cells. The thickness of the zona pellucida and the relative numerical percentages of the several morphologic types of cumulus cells were also evaluated. The optical disector procedure was used for cumulus cell sampling. Volume estimation based on a real physical unique point did not differ from those based on a particular point among many or on a virtual central point, and the mean cumulus cell volume was estimated by using the single section bearing the unique reference point. Quantitative data showed that COCs appear heterogeneous for all studied parameters and that the cumulus mass contains three different cell populations.


Assuntos
Diestro , Oócitos/citologia , Folículo Ovariano/citologia , Animais , Bovinos , Núcleo Celular/ultraestrutura , Tamanho Celular , Feminino , Fixadores , Glutaral , Microscopia/métodos , Inclusão do Tecido , Zona Pelúcida/ultraestrutura
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...