STRUCTURAL ASSESSMENT OF VIOLATIONS OF THE ADAPTIVE MECHANISMS OF ADRENAL CALVESIN THE ACUTE COURSE OF CRYPTOSPORIDIOSIS

The study was the first to assess the adaptation mechanisms disorders of the adrenals of calves in acute cryptosporidiosis. The cryptosporidiosis in patients with symptoms of diarrhea in the farms of the Republic of Tatarstan was diagnosed through formalin-ether sedimentation and following staining of infectious agents by Ziehl-Neelsen acid fast staining method. For specific identification of cryptosporidium in the feces of calves, an enzyme immunoassay kit, “H&R Crypto Rapid Test”, was used to detect cryptosporidium in feces. The agents of cryptosporidiosis of the genus Cryptosporidium were determined in pathological material taken from sick and dead at the age of 5 to 10 days calves. Histological examination of the organs and tissues of calves with the cryptosporidiosis were carried out using generally accepted method of staining of histological sections with hematoxylin and eosin. Structural studies of adrenal cortex and medulla of calves with the cryptosporidiosis revealed significant changes in synthesized hormonal products profiles. The characteristics of intense glucocorticoid biosynthesis were found in the adrenal cortex at the height of disease, as shown by a sharp expansion in zona fasciculate of the cortex, numerous small and large vacuoles in the cytoplasm of spongiocytes and enhanced profiles of capillary net. Intense excretion of glucocorticoids in hemocirculation maximally activated the catabolic processes in the organisms of sick calves. Small number of adrenocorticocytes, the predominance of small hyperchromic nuclei in them and the absence of characteristics of mitotic activity were not edinzona glomerulosa of the cortex that corresponded to the morphological equivalent of retardation of mineralcorticodes biosynthesis. There had been a dramatic increase in cells with characteristics of apotosis among adrenocorticocytes in all zones of the cortex, including the small in width reticular zone. The small catecholamine-synthesizing cells in the medullary area were represented predominantly by small with sharply clarified cytoplasm and small rounded adrenocytes nuclei and by significantly smaller amount of larger noradrenocytes. The found pathological changes in the cortex and medulla of the adrenals characterized the increase of catabolic processes, vascular, metabolic disorders in organisms of calves with the cryptosporidiosis. In view of disorders of adaptation mechanisms and limited plastic resources, a fast death was observed in newborn calves.

Adrenal glands of Spix's yellow-toothed cavy (Galea spixii, Wagler, 1831): morphological and morphometric aspects

Considering the physiological importance and need of greater morphophysiological knowledge of adrenal glands, the aims of present study were compare the morphometric data between left and right adrenal of male and female; perform a histological, scanning and transmission electron microscopy study showing tissue constitution of glands; finally, in order to define the presence and correct site of the cytochrome P450c17 expression in adrenal glands, immunohistochemical study of this enzyme was performed in 18 adrenal glands (right n=9 and left n=9) of nine adult Galea spixii (four males and five females). Right adrenal was more cranially positioned than left adrenal; dimensions (weight, length and width) of right adrenal was larger than left adrenal; no differences between male and female body and adrenal measurements were found; the morphology of cells and different amounts of lipid droplets may be related to the different demands of steroid hormones production, related to each zone of the adrenal cortex; and, the cytochrome P450c17 immunolocalization in fasciculate and reticular zone may be related with synthesis of 17-hydroxy-pregnenolone, 17-hydroxy-progesterone, dehydroepiandrosterone or androstenedione.

Ultrastructure of rhoptry development in Plasmodium falciparum erythrocytic schizonts

Prior to the separation of merozoites from the Plasmodium falciparum schizont, various stage-specific organelles are synthesized and assembled within each merozoite bud. The apical ends of the merozoites are initiated close to the ends of endomitotic spindles. At each of these sites, the nuclear membrane forms coated vesicles, and a single discoidal or cup- like Golgi cisterna appears. Reconstruction from serial sections indicates that this structure receives vesicles from the nuclear envelope and in turn gives off coated vesicles to generate the apical secretory organelles. Rhoptries first form as spheroidal structures and grow by progressive fusion of small vesicles around their margins. As each rhoptry develops, 2 distinctive regions separate within it, an apical reticular zone with electron-lucent areas separated by cords of granular material, and a more homogenously granular basal region. The apical part elongates into the duct, with evidence for further vesicular fusion at the duct apex. The rounded rhoptry base becomes progressively more densely packed to form a spheroidal mass, and compaction also occurs in the duct. Typically, one rhoptry matures before the other. Cryofractured rhoptry membranes show asymmetry in the sizes and numbers of intramembranous particles at the internally- and externally-directed fracture faces.