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1.
Hum Reprod ; 21(4): 986-93, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16361286

RESUMEN

BACKGROUND: The pathophysiology of the testicular damage in varicocele has not been completely understood. Oxidative stress and related sperm DNA damage have been identified as significant causes of male infertility. The current study was designed to determine the extent of sperm nuclear DNA damage in patients with varicocele and to examine its relationship with oxidative stress. METHODS: Semen samples from 55 patients with clinical varicocele and 25 normozoospermic donors were examined. Varicocele sperm samples were classified as normal or abnormal according to World Health Organization guidelines. Sperm DNA damage was evaluated by the sperm chromatin structure assay/flow cytometry and by the terminal deoxyribonucleotidyl transferase-mediated dUTP nick-end labelling (TUNEL) assay. Levels of reactive oxygen species (ROS) and total antioxidant capacity were assessed by a chemiluminescence assay. RESULTS: DNA fragmentation index (DFI) (percentage of sperm with denatured DNA) values and the percentage of TUNEL-positive cells were significantly greater in patients with varicocele, either with normal (DFI, 20.7 +/- 4.0; TUNEL positive, 26.1 +/- 3.2) or with abnormal (DFI, 35.5 +/- 9.0; TUNEL positive, 32.2 +/- 4.1) semen profile, compared with controls (DFI, 7.1 +/- 0.9; TUNEL positive, 14.2 +/- 1.2). Similarly, ROS levels were significantly higher (P < 0.01) in both groups of patients with varicocele. CONCLUSIONS: The presence of a varicocele is associated with high levels of DNA-damage spermatozoa even in the presence of normal semen profile. The results also indicate that oxidative damage is associated with sperm DNA damage in these patients.


Asunto(s)
Daño del ADN , Estrés Oxidativo/fisiología , Espermatozoides/ultraestructura , Varicocele/genética , Biomarcadores , Fragmentación del ADN , Humanos , Etiquetado Corte-Fin in Situ , Masculino , Especies Reactivas de Oxígeno/metabolismo
2.
Ophthalmologica ; 180(6): 301-13, 1980.
Artículo en Alemán | MEDLINE | ID: mdl-7443196

RESUMEN

The structure of the pigment epithelium at the ora serrata is examined in 10 human eyes aged from 31 to 90 years. The cells of the pigment epithelium show a different construction depending on their position relative to the ora. Directly at the ora serrata, in the cohesion band, the cells are higher and contain more pigment granula than those which are situated in a central region. In this sector we sometimes find overlapping of cells, which feigns two layers of epithelium. There are clearly fewer basal folding ins of the pigment epithelial cells at the oral than in the other parts of the retina. At the ora serrata pathological changes start in the 3rd decade of life. They include swelling and later on more or less pronounced cystoid degeneration of the epithelial cells. Within Bruch's membrane two kinds of cells are seen. In the ora gap six types of free cells can be distinguished, whose origin is discussed especially. Probably they originate from the chorioidea, the pigment epithelium and the sensory retina.


Asunto(s)
Epitelio Pigmentado Ocular/ultraestructura , Adulto , Factores de Edad , Anciano , Femenino , Humanos , Masculino , Microscopía Electrónica , Persona de Mediana Edad , Epitelio Pigmentado Ocular/citología , Epitelio Pigmentado Ocular/patología
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