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Biomedical subjects

M M Kaback

Publications and source records attributed to M M Kaback.

At least 91 records · Page 5Linked to original sources
PubMed1971

Adult hemoglobin synthesis by reticulocytes from the human fetus at midtrimester.

The synthesis of adult-type hemoglobin was measured in small samples of peripheral blood cells from 9- to 18-week human fetuses. Hemoglobin indistinguishable from hemoglobin A was identified by ion-exchange chromatography, electrophoresis at pH 8.6, tryptic peptide analysis, and the insensitivity of its synthesis to the action of O-methylthreonine. Synthesis of hemoglobin A accounted for 8 to 14 percent of total hemoglobin synthesis and was demonstrated in as little as 10 microliters of fetal blood. These studies provide sensitive methods for the detection of beta chain types in hemoglobin synthesized by the human fetus at midtrimester. If methods to obtain small quantities of fetal blood at midtrimester become available, these techniques should be applicable to the antenatal detection of sickle cell anemia and related hemoglobinopathies.

Amino Acids↗
PubMed1971

Xeroderma pigmentosum: a rapid sensitive method for prenatal diagnosis.

When normal human cells, capable of repairing ultraviolet-induced lesions in their DNA, are incubated in the thymidine analog 5-bromodeoxyuridine after ultraviolet irradiation, the analog is incorporated into the repaired regions. When such repaired cells are subsequently irradiated with 313-nanometer radiation and placed in alkali, breaks appear in the DNA at sites of incorporation of 5bromodeoxyuridine, inducing a dramatic downward shift in the sedimentation constant of the DNA. Cells from patients with the disease xeroderma pigmentosum, which causes sensitivity to ultraviolet, are incapable or only minimally capable of repair; such cells incorporate little 5-bromodeoxyuridine into their DNA under these conditions and, upon 313-nanometer irradiation and sedimentation in alkali, exhibit only minor shifts in DNA sedimentation constants. When fibroblasts developed from biopsies of normal skin and of skin from patients with xeroderma pigmentosum, as well as cells cultured from midtrimester amniotic fluid, were assayed in this fashion unequivocal differences between normal and xeroderma pigmentosum cells were shown. Xeroderma pigmentosum heterozygotes are clearly distinguishable from homozygous mutants, and results are available 12 hours after irradiation.

Amniocentesis↗
PubMed1971

Comparative production of interferon by human fetal, neonatal, and maternal cells.

Production of interferon was studied in fibroblasts cultured from human fetal, neonatal, and maternal tissue. Human fetal and maternal cells were paired to diminish genetic variability. Fetal cells displayed an increased response to two inducers of interferon, virus and synthetic double-stranded ribopolynucleotide. Fetal cells released 300-fold more interferon than maternal cells on exposure to poly rI:rC. This enhanced capacity for interferon production was consistent in cultures developed from fetal skin obtained between the 10th and 20th gestational week. The response was relatively stable, persisting in cells cultured for 18 generations (about 14 weeks). On infection with Newcastle disease virus, fetal cells produced, on the average, 4 to 6.5 times more interferon than maternal or neonatal cells. The virus was adsorbed with equal efficiency by each type of cell. Increased production is apparently independent of the rates of overall protein synthesis, since fetal and maternal cells have very similar rates of total protein synthesis.

Journal Article↗