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Biomedical subjects

L Zamboni

Publications and source records attributed to L Zamboni.

At least 37 records · Page 2Linked to original sources
PubMed1982

Preliminary observations on the role of the mesonephros in the development of the adrenal cortex.

The interrelationship between mesonephros, adrenal cortex, and gonads was studied in 28- and 31-day old sheep fetuses by means of light microscopy on plastic sections. At these stages, the adrenal cortex is just beginning to develop and mesonephros is undergoing involution; its regression is accompanied by mobilization of cells from the glomerulus of a peculiar nephron situated in the proximal third of the organ, and referred to as "giant" because of its large size. The mobilized cells egress from this glomerulus organized in trabeculae, some of which reach the cranial extremity of the adrenal cortex while others coalesce into a prominent cellular formation which extends uninterrupted toward and into the developing gonads. In previous studies we have shown that the mesonephric cells which colonize the gonads differentiate into sustentacular and interstitial steroidogenic cells; the presence of an analogous cellular migration from the mesonephros to the adrenal cortex now suggests that also the adrenal cortical cells may be of mesonephric origin.

Adrenal Cortex↗
PubMed1982

Ectopic germ cells: natural model for the study of germ cell sexual differentiation.

In the course of a study on the morphogenesis of the adrenal gland in random-bred Swiss albino mice, we noted the presence of ectopic germ cells in the adrenal cortexes and medullas in animals of both sexes, from day 12 1/2 of fetal development to postnatal day 12. Up to day 15 of fetal development, the cells exhibited characteristics of primordial germ cells. At day 17, and irrespective of the sex of the fetus, they all entered meiosis in synchrony with those in the ovary. Postnatally, in females as well as males, all ectopic germ cells displayed morphologic characteristics identical to those of young oocytes in unilaminar ovarian follicles. No germinal elements were seen in the adrenal glands past day 12 of life. Our study shows that mammalian germ cells are capable of undergoing sustained differentiation outside the gonads and that, in ectopic sites, they all differentiate into oocytes as they normally would in the ovary, even in males.

Adrenal Glands↗
PubMed1977

Ultrastructural appearance and morphogenesis of renal glomerular hematoxylin bodies.

The fine morphology of hematoxylin bodies--structures which, by light microscopy, are considered to be pathognomonic for systemic lupus erythematosus--is described in renal glomeruli. These bodies are highly pleomorphic and are predominantly of cellular origin. The nuclear components, which are responsible for the characteristic tinctorial properties, appear as aggregates of clumped chromatin and/or irregular masses of finely granular, moderately dense, lobulated material, generally enveloped by membranes. The cytoplasmic components consist of a multitude of vesicles, vacuoles, degenerating granules, and glycogen. Hematoxylin bodies are usually contained within the bounderies of mesangial cells. A transition from circulating leukocytes to typical hematoxylin bodies could be demonstrated. It is suggested that the changes in leukocytes which culminate in hematoxylin bodies are intiated by the action of antinuclear antibodies and also possibly by the ingestion of immune complexes. This proposed appearance and morphogenesis of hematoxylin bodies is in general agreement with a few previously published investigations on these structures and also with the in vitro counterpart, the lupus erythematosus (LE) cell.

Antibodies, Antinuclear↗
PubMed1976

Hereditary nephritis, deafness and abnormal thrombopoiesis. Study of a new kindred.

A fourth kindred displaying the triad of hereditary nephritis, deafness and thrombocytopenia with giant platelets is described. Renal involvement, a common cause of death amongst afflicted subjects, appears to have a better prognosis in the affected members of this family. Although the electron microscopic appearance of the megakaryocytes in the present case appears similar to that in previously reported cases, we suggest that the "giant" platelets may result from a degenerative process of megakaryocytes leading to nuclear regression and cytoplasmic fragmentation, rather than the usual blebbing process.

Adolescent↗
PubMed1975

Anomalous patterns of mammalian oocyte maturation and fertilization.

This report illustrates some of the errors that may occur during in vivo and in vitro maturation and fertilization of mammalian ova, considers the possible mechanisms accounting for their occurrence, and discusses their functional consequences. Included in the description are anomalies of oocyte and follicular development, i.e., multinucleated oocytes, polyovular follicles, and aberrations of zona pellucida formation. Also considered are deviations from the normal process of oocyte maturation such as chromosomal anomalies, development of abnormal nuclear structures (subnuclei), inhibition of polar body formation and abberations of polar body structure. Anomalies of the process of fertilization such as polyspermia, sperm penetration into polar bodies, and development of multinucleated blastomers in two-cell embryos are also described.

Animals↗