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Biomedical subjects

H H Spencer

Publications and source records attributed to H H Spencer.

At least 19 recordsLinked to original sources
PubMed1975

Chromosome constitution of cells from human gingiva.

This is a study of cells and chromosomes during serial transfer of tissue cultures, starting from the first mitosis occurring before explantation of normal gingival tissues and continuing until a genotypic variation was attained after explantation. From 16 specimens, 9 could be maintained in vitro for varying lengths of time, 7 for more than 50 weeks. In all cases, at 2 months in cultures and afterward, cells were found to be fibroblast-like cells with heteroploid chromosomal complement. The heteroploidy of the cells was due to extrasomy of chromosomes from all groups. However, chromosomes of the me cells before culturing showed the normal diploid number of 46 chromosomes.

Adult↗
PubMed1972

Biosynthesis of hemoglobin Ann Arbor: evidence for catabolic and feedback regulation.

Hemoglobin Ann Arbor, in which arginine replaces leucine in position 80 of the a chain, occurs in aflected individuals in low proportion to hemoglobin A. Biosynthetic studies were perforined on reticulocytes of a patient heterozygous for this hemoglobin. These studies suggested that the low percentage of hemoglobin Ann Arbor is prinlarily due to preferential destruction of the abnormal component. The reduced concentration of alpha Ann Arbor chains was also reflected in a decreased synthesis of normal beta chains.

Amino Acids↗
PubMed1971

Erythrocytes: pits and vacuoles as seen with transmission and scanning electron microscopy.

Vacuoles containing inclusions were observed by transmission electron microscopy in erythrocytes of a splenectomized patient with hemoglobin Ann Arbor. The membranes of these vacuoles became fused with the surface membrane of the red cell, thus opening the vacuoles and exposing their contents to the outside. These vacuoles when they have become thus attached to the cell membrane of the erythrocyte are responsible for the pits observed with scanning electron microscopy.

Cytoplasm↗
PubMed1967

Hydroxyethyl starch: extracellular cryophylactic agent for erythrocytes.

Studies in vitro indicate that hydroxyethyl starch is an effective extracellular cryoprotective agent for erythrocytes. It is as effective as polyvinylpyrrolidone in cryophylactic ability. It is degraded to glucose units in the circulation, is not retained in tissues, and is inexpensive to produce. Changes in the size and degree of hydroxyethylation of the branched-chain starch may result in a more effective cryoprotective agent.

Blood Preservation↗