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Biomedical subjects

E C Jenkins

Publications and source records attributed to E C Jenkins.

At least 91 records · Page 5Linked to original sources
PubMed1983

The effect of oral contraceptives on sister chromatid exchange, blast transformation, mitotic index and micronuclei formation.

Lymphocytes from 5 individuals were cultured to study the effect of mestranol and norethindrone on sister chromatid exchange (SCE), blast transformation, mitotic index and micronuclei formation. Four combinations of the drugs were compared to water and ethanol controls. Some steroid combinations increased the SCE frequency compared to ethanol controls. There was no uniform effect on blast transformation or mitotic index. In 3 individuals, micronuclei formation was reduced in treated cultures. In conclusion, contraceptive steroids may be mutagenic in some individuals.

Adult↗
PubMed1980

A liveborn case of 49,XXXY, + 18.

The first case of a liveborn male infant trisomic for both the X and the No 18 chromosome is presented. The patient had multiple congenital anomalies many of which were similar in appearance to patients with trisomy 18. The proband died after 2 days. Both maternal and paternal karyotypes were normal.

Abnormalities, Multiple↗
PubMed1979

Slow versus fast postthaw dilution for the recovery of lymphocytes in whole blood frozen in either dimethyl sulfoxide or glycerol.

It was previously shown by the authors that human whole blood was cryoprotected by dimethyl sulfoxide (DMSO) for use as inoculum in short-term lymphocyte cultures. That procedure utilized a fast postthaw dilution where the cryoprotective agent was diluted in two steps. In this paper it is shown that a five-step 'slow' dilution technique is much superior to the two-step 'fast' dilution procedure, which significantly revises our original report of 1972. This method has strikingly improved the degree of blastogenic response to phytohemagglutinin as measured by 3H-thymidine incorporation. The increase in amount of tritium incorporation was seen in cultures which were protected with either DMSO or glycerol. A similar effect was observed in unfrozen control cultures exposed to either cryoprotectant.

Blood Preservation↗
PubMed1977

De novo trisomy 9pter leads to q13.

A case of de novo trisomy 9p was observed. Cytogenetic analysis of G-, R-, Q-, and C-banded preparations revealed a karyotypic description of 47,XY,+del(9)(pter leads to q13). In addition to the principal characteristics of the 9p trisomy syndrome, the child presented with skeletal and urogenital abnormalities. It appears that certain clinical abnormalities are due to trisomy of 9q1.

Abnormalities, Multiple↗
PubMed1977

A case of 46,XY,t(1;13) (q24;q32) with mental retardation.

A 14-year-old mentally retarded boy with congenital malformations of unknown etiology was found to have a de novo apparently balanced reciprocal translocation between chromosomal arms 1q and 13q. There is only one other case where a similar translocation was observed but the breakpoints could be localized only by regions and the individual was not mentally retarded.

Abnormalities, Multiple↗
PubMed1977

Human sister chromatid exchange caused by methylazoxymethanol acetate.

The incidence of sister chromatid exchange was determined in human leucocyte cultures treated with methylazoxymethanol acetate. In all individuals examined, treated cultures manifested a significantly higher frequency of sister chromatid exchanges than controls. Two concentrations of MAM AC were tested in blood cultures from nine individuals. The concentrations varied from individual to individual since they were determined by means of individual dose-response curves, which involved [3H]-thymidine incorporation in PHA-stimulated short-term lymphocyte cultures versus MAM AC contraction. The lower concentration was less than the TD50 dose. Compared to control cultures, the lower concentration caused a higher incidence of sister chromatid exchange in eight of nine individuals. The cumulative mean value for all control cultures was 5.32 exchanges per cell while that for cultures treated with the higher concentration was 10.73.

Adult↗
PubMed1976

PHA response and methylazoxymethanol acetate.

Several reports have indicated the mutagenicity of the cycasin aglycone, methyl azoxymethanol (MAM). Van Den Berg and Ball (1972) have demonstrated the inhibitory effects of MAM acetate (MAMac), a more stable form of the aglycone, on DNA synthesis and cell proliferation in HeLa cells. The purpose of this study was to observe the effects of MAMac on blastogenesis in the human short-term leucocyte culture system. A depression in blastogenesis by MAMac was observed cytologically derived from two individuals. The same effect was observed utilizing [3H] thymidine as an indicator of blastogenesis in a series of cultures from 11 male individuals exposed to varying doses of MAMac, ranging from 5 through 800 mug/ml.

Azo Compounds↗
PubMed1976

A child with presumptive monosomy 21 (45,XY,-21) in a family in which some members are Gq-.

Presumptive monosomy for chromosome 21 was found in a male child with multiple malformations and severe psychomotor retardation. Chromosome analyses of cells from blood and skin samples were performed at intervals during the first few years of his life. In preparations stained with nonbanding was well as quinacrine, Giemsa, and reverse acridine orange banding techniques, only one No. 21 chromosome could be detected with no apparent abnormalities of the other chromosomes. The proband's phenotypically normal father, paternal grandfather, brother, and paternal aunt have a deletion for a short segment of the long arm of a G-group chromosome. Genetic-marker studies allow the exclusion of a number of blood groups as being associated with No 21. There is inconclusive evidence suggesting that expression of the Duffy blood group, which has been mapped to chromosome 1, may be influenced by genetic information on chromosome 21. This family is of potential value for further gene-mapping studies.

Abnormalities, Multiple↗