Structure and histophysiological considerations on the arterial wall of the dog / Estructura y aspectos histofisiológicos de la pared arterial del perro

This paper described the architecture of the dog aortic arterial wall focused in the ascendant; thoracic descendent, and abdominal parts of the aorta. Furthermore, in this study we analyzed the wall structure of the right external iliac artery and the left vertebral artery of dog aiming to compare their architectural patterns with the aortic wall mainly in abdominal aortic part, which was structured by a mixed muscular and connective matrix equilibrated elements. The variables analyzed were the thickness of each mural layer; the number of elastic lamellae, mainly localized into the medial layer structure, and the diameters of each aortic segment. The aortic structure showed a typical elastic pattern in the ascendant and descendant thoracic parts, but in its abdominal segment a lesser presence of elastic lamellae permitted to classify it with a mixed mural composition. The aortic segments mainly presented variable amounts of smooth muscle cells and connective matrix assuming a meshwork pattern. Furthermore, smooth muscle cells were seen intermingled with connective lamellae and fibers forming the complex meshwork related, which certainly helped to guarantee the aortic mural integrity during the aortic blood flow.

El objetivo de este trabajo fue describir la estructura histológica de la aorta del perro adulto, a través del análisis morfométrico. Fueron estudiados los tres segmentos de la aorta, ascendente y descendente torácicos, y el segmento abdominal inferior a los riñones. Esta última porción presentó un patrón estructural mixto, con tejido muscular liso y conectivo, con equilibrio entre las células musculares lisas y el componente mural tipo estroma, con elementos fibrosos y laminillas elásticas. En las otras partes de la aorta, se observó el clásico patrón elástico en la estructura mural, con una mayor proporción de los componentes activos (musculares lisos) que los pasivos, o sea, laminillas y fibras conectivas. El número de las laminillas elásticas fue decreciente desde la aorta ascendente en dirección a la parte abdominal de la aorta. Los diámetros de los tres segmentos tiñeron de manera similar. La comparación entre la estructura mural de la aorta y la histología de la arteria iliaca interna derecha y arteria subclavia izquierda, ambas musculares, fueron analizadas de manera objetiva, encontrando diferencias en el patrón mural aórtico, principalmente en el segmento aórtico terminal.

Histofisiologia e classificação das queimaduras: consequencias locais e sistêmicas das perdas teciduais em pacientes queimados / Histophysiology and classification of burn: consequences of local systems and tissue loss in patients burnt

As queimaduras são lesões desencadeadas por agentes físicos, químicos, elétricos e térmicos que resultam em níveis variados de perda tecidual. O grau com que estas lesões danificam a pele depende de muitas variáveis, incluindo a duração e intensidade de contato com o agente agressor, a espessura da pele da região anatômica acometida, tamanho da área exposta, vascularização local e idade. Ainda, a perda tecidual é um dos fatores prognósticos destas lesões fornecendo clinicamente a base para a classificação destas lesões, o que faz com que a compreensão da histomorfologia da pele seja fundamental para o entendimento da fisiopatologia das queimaduras. O presente trabalho aborda os mecanismos fisiopatológicos envolvidos nas queimaduras e os vários critérios de classificação destas lesões, buscando fornecer subsídios teóricos para tal compreensão através de uma revisão de literatura abordando a histofisiologia da pele.

Burns are injuries triggered by physical, chemical, electrical and thermal result in varying levels of tissue loss. The degree to which these lesions damage the skin depends on many variables, including duration and intensity of contact with the offending agent, the skin thickness of the anatomical region affected, the size of the exposed area, local vascularization and age. In addition, tissue loss is one of the prognostic factors of these lesions clinically providing the basis for the classification of these lesions and the understanding of the morphology of skin is essential to understanding the pathophysiology of burns. The present paper discusses the pathophysiological mechanisms involved in burns and various criteria for classifying these lesions and to provide theoretical understanding for such a thorough review of literature dealing with histophysiology skin.

Vas deferens surface epithelium of Agouti paca: fine structural features / Epitelio del conducto deferente de Agouti paca: observaciones de estructura fina

The surface epithelium of the vas deferens of Agouti paca, a wild and large South American rodent, was basically formed by principal and basal cells being only the principal cells related to endocytosis processes and also secretion taking base on their cytoplasmic ultrastructural features. Principal cell of vas deferens epithelium were characterized mainly by presence of vesicles with several shapes, sizes and internalized content at their apical cytoplasm occurring smaller pits and pale small vesicles seen next to the apical brush border of microvillus. Moreover, coated vesicles, smooth surface vesicles and great vesicles; multivesicular bodies, endosomes and lysosomes were seen. Presence of an apocrine secretory apparatus was also viewed, showing apical cytoplasmic expansions protruding into the vas deferens luminal compartment. The basal flattened cells, without luminal surface contact, occurred next to the basement membrane of the ductus, and did no exhibit special ultrastructural features.

El epitelio que recubre la luz del conducto deferente de la laca (Agouti paca), un roedor silvestre de Sudamérica, está formado por células principales (P) y básales (B), en donde las células principales están asociadas a los procesos de endocitosis y secreción, teniendo una base en su característica ultraestructural citoplasmática. Las células principales de los vasos deferentes del epitelio se caracteriza principalmente por la presencia de vesículas con variadas formas, tamaños y contenido interior en su citoplasma apical produciendo pequeñas invaginaciones y pequeñas vesículas pálidas ubicadas continuas al borde en cepillo de las microveilosidades apicales. Además, fueron observados, vesículas de superficie lisa y vesículas de gran tamaño; órganos multivesiculares, endosomas y lisosomas. También se observó la presencia de un aparato secretor apocrino, con expansiones citoplasmáticas apicales que se protruyen en el compartimiento luminar del conducto deferente. Células básales aplanadas, sin contacto con la superficie luminal, se encuentran junto a la membrana basal del conducto, las que no presentan características ultraestructurales especiales.

Response of blood glucose, hepatic glycogen and pancreatic islets to treatment of sulphydryl inhibitors in Clarias batrachus L.

The correlative effects of the two sulphydryl inhibitors viz., the mono-and dithiol reagent, alloxan and cobalt chloride, were studied in the fresh water air breathing catfish, Clarias batrachus. Alloxan induced a typical mammalian-like triphasic response and necrobiotic changes in the islet β-cells. Cobalt chloride elicited a discontinuous hyperglycemia with cytopathological changes in β-cells following nearly the same sequence as those induced by alloxan. However, the α-cells of cobalt-treated fish showed, unlike those after alloxanization, specific degranulation, vacuolization and nuclear enlargement. The changes in the hepatic glycogen content of two experimental groups were observed to be equal. Both the drugs appeared to be detrimental to the normal islet function and were, thus, overtly or potentially diabetogenic agents to the fish.