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Biomedical subjects

A Chiba

Publications and source records attributed to A Chiba.

At least 163 records · Page 9Linked to original sources
PubMed1979

Histological observation of some of the endocrine glands in the sterile carp-funa hybrid (F1), with special reference to the hypophysis.

Some endocrine glands of the carp-funa hybrids were studied with a light microscope to elucidate their detailed structure and the possible causal factor of sterility in the males. Adult specimens of carp (Cyprinus carpio), gengoroh-buna (Carassius auratus cuvieri), and their hybrid (F1) were examined. The hybrid males are sterile as manifested by the failure of meiosis and seminomatous neoplasm in their testes. The hybrid females revealed well-developed ovaries, but their fertility was not tested. The hybrid hypophysis shows an intermediate condition between the parent species in the grade of ramification of the pars nervosa into the pars intermedia. Among seven types of granular cells demonstrated in the adenohypophysis, certain degenerative and anomalous changes are recognized only in the gonadotrophs of the hybrid hypophysis, especially in the female. These changes are discussed as a possible cause of sterility. A considerable amount of aldehyde fuchsin stainable neurosecretory material occurs in the cells of the nucleus preopticus and in the pars nervosa. The nucleus lateralis tuberis exhibits a histologically healthy condition.

Animals↗
PubMed1978

Histological observations on some of the endocrine glands in the ironfish, with special regard to the hypophysis.

Endocrine glands of the ironfish were studied light microscopically to elucidate the relationship between the races of the genus Carassius. The rostral pars distalis of the adenohypophysis consists mainly of acidophils corresponding to prolactin cells and lead-hematoxylin positive cells corresponding to corticotrophs (ACTH cells). The prolactin cells are obviously arranged in the form of follicles. The proximal pars distalis contains orangenophils (STH cells) and two types of basophils (TSH and GTH cells). In the pars intermedia, three types of cells are identified: periodic acid Schiff positive cells, lead-hematoxylin stainable cells and orangenophils containing PAS positive coarse granules. In addition, small agranular cells are seldom demonstrated in the entire adenohypophysis. A considerable amount of aldehyde fuchsin positive neurosecretory material is laden in the cells of the nucleus preopticus and in the pars nervosa. The nucleus lateralis tuberis is composed of three portions: pars anterior, pars posterior, and pars lateralis. The thyroid follicles found in the pharyngeal region and head kidney show a mild state of activity. The interrenal cells intermingled with the chromaffin cells have a considerable amount of eosinophil cytoplasm. Judging from the gonadal condition, the breeding season of the ironfish may extend to the end of July.

Animals↗
PubMed1977

Glycosaminoglycans in congenital pseudarthrosis.

Light and electron microscopic studies on cells and matrices of congenital pseudarthrosis of the femur of a 5.5-year-old male revealed three areas with different morphological features; a fibrous area, a cartilaginous area and an osseous area. Glycosaminoglycans were isolated from each of the three areas and characterized by the degradation with chondroitinases. Although chondroitin sulfate was the major component in all regions, a significant amount of dermatan sulfate occurred in the fibrous area. A small amount of hyaluronic acid was found in both fibrous and osseous areas. These suggest that the peculiar composition of glycosaminoglycans in the affected part may account for some clinical aspects of the disease which resists treatment.

Child, Preschool↗
PubMed1976

Changes in the cells of the adenohypophysis associated with the diadromous migration of the threespine stickleback, Gasterosteus aculeatus L.

The adenohypophysis of the threespine stickleback, Gasterosteus aculeatus, was studied light-microscopically to determine and estimate the cell types and their function. For these purposes, the adult specimens obtained during the period from migration to spawning were examined. Further, the juveniles caught in the spawning bed were subjected artificially to sea water. The rostral pars distalis (RPD) consists mainly of two types of cells: dorsally shifted lead hematoxylin (PbH)-positive cells bordering the neurohypophysis correspond to corticotrophs, and antero-ventrally shifted acidophil cells are identified as prolactin cells. The latter undergo marked hypertrophy and active state just at the time of entering the river (February), while no detectable change was seen in the former throughout anadromous migration. The role of prolactin on the osmoregulation in freshwater environment is thus suggested. The proximal pars distalis (PPD) consists mainly of two cell types: the basophil cells in round shape are regarded as the gonadotrophs and the acidophil cells in ellipsoid shape are considered to be somatotrophs. The size of the gonadotrophs reaches the maximum at the time of spawning. A few AF-positive cells of elongate shape occur in the dorsal region and are identified as thyrotrophs. In the pars intermedia (PI), two types of cells are discernible: PAS-positive and PAS-negative cells. The latter attained their maximal size in the earliest time of anadromous migration.

Animals↗