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Biomedical subjects

J Sternberg

Publications and source records attributed to J Sternberg.

At least 37 records · Page 2Linked to original sources
PubMed1988

Nuclear DNA content of Trypanosoma congolense.

We have measured the nuclear DNA content of the major life cycle stages of Trypanosoma congolense, in two clones of geographically distant origin. We find that nuclear DNA content in epimastigote, mammalian blood-stream and metacyclic forms is constant and that the nuclear DNA contents of the two clones were 0.1 pg and 0.09 pg, respectively.

Animals↗
PubMed1986

The relationship between emerging neural crest cells and basement membranes in the trunk of the mouse embryo: a TEM and immunocytochemical study.

The earliest stage of neural crest cell (NCC) migration is characterized by an epitheliomesenchymal transformation, as the cells leave the neural tube. There is evidence that in a number of cell systems this transformation is accompanied by alteration or depletion of associated basement membranes. This study examines the ultrastructural relationship between mouse NCCs and adjacent basement membranes during the earliest stages of migration from the neural tube. Basement membranes were identified by transmission electron microscopy (TEM) and immunofluorescence using antibodies to type-IV collagen. The ultrastructural features of NCCs and their relationship with surrounding tissues were also examined using TEM. In the dorsal region of the neural tube, from which NCCs originate, the basement membrane was depleted or absent, and with the immunofluorescence technique it was shown that this pattern was reflected in a deficit of type-IV collagen. TEM observations indicated that ultrastructurally NCCs differ from their neuroepithelial neighbours only in overall cell shape and their relationship to other cells and the extracellular matrix.

Animals↗
PubMed1986

Distribution of fibronectin, laminin and entactin in the environment of migrating neural crest cells in early mouse embryos.

The distribution of the extracellular matrix molecules fibronectin, laminin and entactin was studied in frozen sections of 9 1/2-day mouse embryos in order to relate their presence to neural crest cell migration. It was found that all three components were present in basement membranes, laminin and entactin being mainly restricted to these. Fibronectin was present at high levels in basement membranes and extracellular spaces throughout the embryo, including the regions of neural crest cell migration. Fibronectin is known to affect migration in a variety of cell systems, so its presence in the embryo at the time of migration may indicate that it is influencing cell movement. This influence is likely to be via the cell surface through interactions with other matrix components such as glycosaminoglycans, and possibly entactin and laminin.

Animals↗
PubMed1983

Dot-blotting--a novel screening assay for antibodies in hybridoma cultures.

A novel solid phase radioimmunoassay using nitrocellulose filters, is described. The method is of particular value in screening hybridoma cultures for monoclonal antibodies against chromosomal protein. Also it permits detection of antibodies directed against epitopes stable to SDS denaturation.

Animals↗
PubMed1978

Effect of vitamin E on post irradiation death in mice.

The 30-day survival after exposure to 800 Rad 60Co gamma radiation has been compared for female mice maintained on vitamin E deficient, vitamin E supplemented or regular lab rations before and/or after irradiation. Pre- or post-irradiation dietary supplementation had no effect on survival; however, injection of alpha-tocopherol immediately after irradiation significantly reduced radiation lethality.

Animals↗
PubMed1978

Bilateral renal cell carcinoma.

Bilateral renal cell carcinoma was diagnosed simultaneously in 6 patients and sequentially in 4 patients, 3 to 14 years after the first tumor had been removed by nephrectomy. Four patients treated conservatively with incomplete excision of the malignant disease are alive 18 months to 14 years after diagnosis. Oue experience suggests that a radical excision, requiring renal dialysis or transplantation, is seldom warranted.

Adenocarcinoma↗
PubMed1973

Radiation and pregnancy.

Irradiation during pregnancy may occur either as the result of radioactive pollution of the environment, or during a medical procedure using x-rays or radionuclides. While the former is usually unforeseeable, the latter is known and accepted by both physician and patient.Recent statistics estimate that about one quarter of pregnant women have had a radiographic experience during the pregnancy, either for obstetrical reasons or in the course of medical and dental examinations. The amount of radiation delivered to the fetus is in the range of one rad or less. Radionuclidic procedures may result in fetal radiocontamination, chiefly after placental transfer and fetal uptake. Radioiodine, radioactive calcium and selenomethionine are dangerous for the fetus, since they cross the placenta freely and are taken up by fetal tissues. The labelled proteins, radiocolloids and some mercury compounds remain in the maternal compartment and therefore can affect the fetus only through their gamma radiation at some distance from the fetus.The teratogenic effect, the leukemogenic threshold and the lowered resistance to neonatal infections have been demonstrated after irradiation with doses far higher than those encountered during diagnostic applications of ionizing radiation. Statistical data suggest an increase of susceptibility to leukemia in infancy after intra-uterine irradiation at a diagnostic level. Cytogenic analysis may.... offer valuable data for the establishment of the extent of radiation damage.

Chromosome Aberrations↗