PubMed Health⌕ Search

Biomedical subjects

C J Chapman

Publications and source records attributed to C J Chapman.

At least 91 records · Page 5Linked to original sources

Two cases of ring chromosome 11.

Two cases of ring chromosome 11 are reported. Both had mental retardation, microcephaly, and short stature. High resolution G banding in case 1 showed no visible loss of chromatin, the karyotype being assessed as 46,XX,r(11) (p15 X 4q2 X 5). In case 2, a Wilm's tumour developed at 8 months and the child died at 18 months. Cytogenetic analysis by Q banding demonstrated minimal chromosome deletion and the karyotype was considered to be 46,XY,r(11) (p15q25).

Abnormalities, Multiple↗

Partial trisomy 14q24 leads to qter.

A newborn male with partial trisomy for the distal part of the long arm of chromosome 14 (14q24 leads to qter) is described. The anomaly arose as an adjacent 1 meiotic segregation product from a balanced translocation t(11;14) (q25;q24) in the mother (figure). To our knowledge only one previous case involving the same segment has been reported. The karyotype was confirmed as 46,XY,der(11),t(11;14)(q25;q24) mat.

Chromosomes, Human, 13-15↗

Lipid composition and (Na+ + K+)-ATPase activity in rat lens during triparanol-induced cataract formation.

The development of triparanol cataracts in rats is accompanied by the loss of lens (Na+ + K+)-ATPase activity and by alteration in the lens content and composition of phospholipids, sterols and phospholipid acyl groups. The lipid changes occur along the same time course as the loss of (NA+ + K+)-ATPase activity. Triparanol feeding produces a decrease in lens phospholipid content. The percentage contents of phosphatidylcholine and phosphatidyl-serine decrease while the content of sphingomyelin substantially increases. The amounts of oleic acid in lens phospholipids decrease while stearic and palmitic acids increase; however, these changes are relatively small. Sterol content is also decreased while the percentage content of desmosterol increases markedly. Feeding of the cataractogenic agents galactose and diazacholesterol also alters the lens lipid compositions and (Na+ + K+)-ATPase activity. A loss of phosphatidylserine is the only change in lipid properties which always accompanies a loss of the enzyme activity. The possible relationships between the lens content of phosphatidylserine, (Na+ + K+)-ATPase activity and the mechanism of triparanol-induced cataract formation are discussed.

Animals↗

Galactosaemia: estimated live birth incidence in New Zealand.

194 cord blood samples were studied in both a fluorimetric assay and an electrophoresis method for Gal-1-PUT. From this the expected live birth incidence was 1:37000. The New Zealand neonatal screening programme has detected 5 cases in 223326 live births--an apparent incidence of 1:44600. The Beutler testing of dried blood spots collected on filter paper cards is a satisfactory method of detecting galactosaemia in the neonate.

Fetal Blood↗

Familial leukaemia: a study of 909 families.

A family survey was conducted among 909 patients with leukaemia of all types, with the purpose of establishing the incidence of further cases of leukaemia among relatives. Among a total of 41,807 relatives 8,349 were deceased, and the cause of death was objectively confirmed in 5,011. 72 patients had one or more relatives with leukaemia. First degree relatives with leukaemia were much more frequent in families of patients with chronic lymphocytic than in those of patients with chronic granulocytic leukaemia. The incidence of leukaemia among first degree relatives was established to be 2.8-3.0 times, among more distant relatives about 2.3 times, and overall about 2.5 times that expected. This excess is of the order of that observed in relatives of patients with certain solid tumors. Genetic factors may have accounted for much of the excess incidence in chronic lymphocytic and acute leukaemia, but there was little evidence for a genetic background in chronic granulocytic leukaemia. With the possible exception of one family with multiple cases, a simple Mendelian mechanism did not appear to be involved in the leukaemia families investigated. It appeared more likely that a polygenic mechanism led to a heightened susceptibility to the disease in these families.

Acute Disease↗

A genetic study of bipolar affective disorder.

A group of 46 bipolar probands and their first degree relatives were studied. A high rate of affective disorder (19.6 per cent) was found, including both unipolar (13.2 percent) and bipolar (6.4 per cent) types, with females predominating (3 : 1). The presence of four fatherson pairs suffering from affective disorder made the hypothesis of X-linked dominance untenable. Results compatible with polygenic inheritance were found, using both Slater's and Falconer's methods. There was no evidence for assortative mating or for increased total number of females (both well and ill) among first degree relatives. The probands and affectively ill first degree relatives who have died show an alarmingly high rate of suicide (46 per cent). Other forms of mental disorder, including alcoholism, were no more common than in the rest of the community.

Adult↗

Nucleic acid synthesis in the chloroplasts of Acetabularia mediterranea.

Radioautographic and radiochemical techniques were used to establish the presence of replicating DNA in the chloroplasts of Acetabularia mediterranea. These techniques also demonstrated that these chloroplasts synthesize RNA. It was found that label from thymine was also incorporated into DNA and RNA in these chloroplasts. With the establishment of protein and nucleic acid synthesis in Acetabularia chloroplasts, it is clear that these chloroplasts carry out those metabolic processes which are most characteristic of autonomous cells.

Chloroplasts↗