RESUMEN
The character of the cell membrane component destruction of the human epidermis when kept in a humid camera at 4 degrees or 37 degrees C was studied electron microscopically and by a freezing-chopping method. Intermembranous proteins undergo considerable changes and are more labile than a lipid membranous component.
Asunto(s)
Autólisis/patología , Epidermis/ultraestructura , Membrana Celular/ultraestructura , Técnica de Fractura por Congelación/métodos , Humanos , Lípidos de la Membrana/análisis , Proteínas de la Membrana/ultraestructura , Microscopía ElectrónicaRESUMEN
Ultrathin slices from the human abdominal skin and platinum-carbonic replicas, obtained by means of the freeze-fracture method have been studied electron microscopically. Transmembranous proteins are revealed on the membrane surface as membrane-bound particles with the diameter 5-7 nm. They mainly concentrate on the membrane protoplasmic surface. Certain difference is noted in distribution of tonofibrils in cytoplasm of the epidermal cells, when various methods for preparation of specimens to be investigated are used. Predominance of the freeze-fracture method comparing to the routine method of electron microscopy is discussed, since the specimens do not subjected to fixation, dehydration and resin saturation.
Asunto(s)
Desmosomas/ultraestructura , Células Epidérmicas , Uniones Intercelulares/ultraestructura , Queratinocitos/ultraestructura , Membrana Celular/fisiología , Membrana Celular/ultraestructura , Desmosomas/fisiología , Secciones por Congelación , Humanos , Uniones Intercelulares/fisiología , Microscopía ElectrónicaAsunto(s)
Pueblo Asiatico , Población Negra , Células Epidérmicas , Población Blanca , Adolescente , Adulto , Niño , Humanos , Masculino , Melanocitos/citología , Microscopía Electrónica , Persona de Mediana EdadRESUMEN
The skin of the negroid race albinos is studied light- and electron-microscopically. Morphological alterations, as compared to control, consist of the horny layer thickening, increase of the cellularity in the epidermis, appearance of numerous pronounced tonofibrillar-keratohyaline complexes in the granular cells and a well developed network of dense bundles of tonofibrils in the spinous layer. Melanocytes and Langerhans cells are similar by their structure and number to those in the control. The protein skeletons of melanosomes in keratinocytes and melanocytes are practically unchanged but they are completely deprived of melanine biopolymer. The dermal macrophages do not contain a melanin pigment. The morphological features of the albinos epidermis, particularly the horny layer thickening, increase of the cellularity and the presence of pronounced tonofibrillar-keratohyaline complexes represent most likely a compensatory protective mechanism against ultraviolet radiation.
Asunto(s)
Albinismo/patología , Población Negra , Epidermis/patología , Células de Langerhans/patología , Melanocitos/patología , Recuento de Células , Epidermis/ultraestructura , Humanos , Células de Langerhans/ultraestructura , Melaninas/deficiencia , Melanocitos/metabolismo , Melanocitos/ultraestructura , Microscopía ElectrónicaRESUMEN
Two types of melanocytes differing in their ultrastructural organization--active and "spent," or reserve--are present in the adult human epidermis. In active melanocytes, intensive melanogenesis takes place, and six stages of melanosomes development can be distinguished in them. The "spent" melanocytes do not contain premelanosomes, and the presence of glycogen inside and around them is evidently indicative of a phase preceding restoration of their function.
Asunto(s)
Melanocitos/ultraestructura , Adulto , Anciano , Citoesqueleto/ultraestructura , Desmosomas/ultraestructura , Glucógeno/metabolismo , Histocitoquímica , Humanos , Melaninas/biosíntesis , Melaninas/efectos de la radiación , Melanocitos/metabolismo , Persona de Mediana Edad , Monofenol Monooxigenasa/metabolismo , Piel/citología , Rayos UltravioletaRESUMEN
The data on complex histochemical and electron histochemical investigation reflecting specificity of the reactions applied in histochemical practice to reveal melanin are represented. Various ultrastructural localization of the substance is demonstrated both with silver and iron use (this demonstrate nonspecificity of the reactions mentioned above to melanin). Ultrastructures possessing affinity to the metal ions involved are detected; possible mechanisms of interaction between silver and iron with different cellular elements are suggested.
Asunto(s)
Melaninas/metabolismo , Piel/metabolismo , Adulto , Femenino , Ferricianuros , Histocitoquímica/métodos , Humanos , Hierro , Masculino , Microscopía Electrónica , Persona de Mediana Edad , Plata , Piel/ultraestructuraRESUMEN
The guthymine medication of a severe shock in rats started 10-20 minutes after injury is shown to eliminate energy metabolism disorders in the brain, liver and kidneys. In the brain of the guthamyine treated rats even a somewhat reduced adenosinetriphosphate content was demonstrable. Administration of guthymine together with polyglucin to cats in a torpid phase of the shock did not effect treir survival, but shortened the life-span of the test animals as compared to controls (receiving polyglucin alone). With guthymine addid to polyglucin the lactate and pyruvate concentration in the blood remained unchanged.