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D A Aitken

Publications and source records attributed to D A Aitken.

At least 73 records · Page 4Linked to original sources
PubMed1987

Growth and characterization of rabbit corneal cells in vitro.

Primary organ cultures of rabbit corneal epithelium, stroma, and endothelium were established by microdissection. Secondary cultures of epithelial cells, keratocytes, and endothelial cells were established by serial passage. The doubling time for epithelial cells and keratocytes was 18 h, and endothelial cells doubled their number in 5 days. Ultrastructural studies demonstrated characteristic morphological, nuclear, and cytoplasmic features of corneal epithelial cells, keratocytes, and endothelial cells and confirmed the identity of the cell lines. The purity of the three distinct cell types was ascertained by indirect immunofluorescence techniques, using antibodies against keratin, which identified epithelial cells, and fibronectin, which identified keratocytes and endothelial cells. The indirect immunofluorescence technique represents a simple method to screen an aliquot of a cell suspension and determine the purity of corneal cells grown in vitro.

Animals↗
PubMed1987

Multipoint linkage analysis of steroid sulfatase (X-linked ichthyosis) and distal Xp markers.

Six families with steroid sulfatase deficiency (STS; X-linked ichthyosis) have been studied with the Xg blood group (XG) and the DNA markers dic56 (DXS143), 782 (DXS85), pD2 (DXS43), and GMGX9. Carrier status of females was determined by assay of STS in hair roots. GMGX9 detects a frequent restriction fragment length polymorphism and also identifies a deletion in the majority of families with STS deficiency, including five of the six reported here. The linkage relationship of this marker to the others was studied in normal three-generation families yielding 32 phase-known meioses informative for two or more markers. No recombinants were observed between STS and GMGX9, giving a maximum lod score of 8.73 at zero recombination. Multipoint linkage analysis taking STS and GMGX9 as a single locus and incorporating two-point marker data and STS-XG data from published studies gave the map (Sequence: see text). This order was 2.4 times more likely than with (STS,GMGX9) and dic56 reversed and is supported by our findings in a male with steroid sulfatase deficiency due to a deletion of Xp22.3 which encompasses the XG locus. He is deleted for GMGX9 but shows normal hybridization to dic56 and 782.

Chromosome Mapping↗
PubMed1986

Duchenne muscular dystrophy due to familial Xp21 deletion detectable by DNA analysis and flow cytometry.

We report two male cousins with Duchenne muscular dystrophy (DMD) in whom cytogenetic studies have shown a small interstitial deletion at Xp21. The lesion is readily detectable in patients and carriers by flow cytometry which indicates that approximately 6000 kb of DNA are deleted in each case. The DNA markers OTC, C7, and B24 are present in the deleted X chromosome but 87-8, 87-1, and 754 are absent. Despite apparently identical deletions one affected boy has profound mental handicap while the other is only mildly retarded. The results confirm the assignment of familial DMD to Xp21 and illustrate the value of flow cytometry in improving the precision of chromosome analysis. We have also undertaken flow cytometry in a cell line from a previously reported DMD patient with a de novo Xp21 deletion who had, in addition, chronic granulomatous disease, retinitis pigmentosa, and the McLeod syndrome. The results indicate that the amount of DNA deleted from the X is similar in both families despite the striking differences in phenotype.

Child↗
PubMed1986

Age-related changes in the human outflow apparatus.

Tissue from 53 human eyes was used for qualitative and quantitative morphological study (light microscopy and electron microscopy) of age-related changes in the human outflow apparatus. The specimen source was surgical procedures. Qualitative observations showed that the general configuration of the trabecular meshwork changed gradually with age, from a long wedge shape to a shorter, more rhomboidal form. The scleral spur became more prominent, the uveal meshwork more compact, and localized canal closure increased in incidence. Intercellular cytoplasmic processes between neighboring trabecular endothelial cells were less evident and areas of trabecular denudation were frequently observed in older eyes. Quantitative light microscopic studies showed a progressive thickening of the trabeculae, and the numbers of giant vacuoles in the lining endothelium of Schlemm's canal decreasing significantly with age. Morphometric analysis of the cribriform layer (transmission electron microscopy) showed that there was a change in the character of the extracellular materials with an increase in the deposition of electron dense plaques and a decrease in the ground substances from the fifth decade onwards.

Adolescent↗
PubMed1986

Early prenatal investigation of a pregnancy at risk of adenosine deaminase deficiency using chorionic villi.

A pregnancy at risk for adenosine deaminase deficiency and severe combined immunodeficiency disease was investigated using samples of chorionic villi obtained during the eighth week of pregnancy. Adenosine deaminase levels suggested that the fetus was a probable carrier and that a diagnosis of severe combined immunodeficiency disease could be excluded. Enzyme and chromosome results were available within 24 hours of the chorionic villous sampling procedure, and were confirmed on amniotic fluid cell cultures after amniocentesis at 17 weeks' gestation and on cord blood at delivery.

Adenosine Deaminase↗
PubMed1986

Herpes simplex virus in the cornea; an ultrastructural study on viral reactivation.

Infectious HSV was isolated from the corneal disc of a patient with chronic stromal keratitis. A morphological study was performed on the corneal tissue after detection of HSV by organ culture. The characteristic features of HSV replication were observed within the keratocytes, including formation of nucleocapsid structures; encapsidation of viral DNA; envelopment and egress of virons. The following effects of viral replication upon cells were seen, margination and condensation of nuclear chromatin, formation of aberrant viral structures, re-duplication of nuclear membranes and cellular destruction. This study demonstrates that HSV replication occurs within keratocytes. HSV replication is an important step in the evolution of disciform herpetic keratitis.

Adult↗
PubMed1985

Quantitative variation in cystic fibrosis-associated proteins in cystic fibrosis patients, carriers, and controls.

Serum samples from patients with cystic fibrosis (CF), obligate heterozygotes, and normal controls have been examined by isoelectric focusing (IEF). Our results suggest that cystic fibrosis protein (CFP) is a normal serum protein exhibiting quantitative variation primarily dependent on possession of the CF allele. It is concluded that detection of CFP by IEF is an inappropriate screening test for the CF gene due to lack of specificity.

Alleles↗
PubMed1982

Duncan Guthrie Institute of Medical Genetics, Glasgow, University of Glasgow, Scotland.

Unbalanced chromosome aberrations detected by routine chromosome diagnostic services can be used for gene mapping by gene dosage. This procedure, once discredited by early observations in Down's syndrome, has now provided some of the most precise intrachromosomal gene localizations known and these are reviewed. Cytogeneticists have an obligation to see that every opportunity is taken to obtain mapping information from suitable cases. Interpretation of cytogenetic findings may be improved by application of appropriate gene dosage studies, and examples are described in which a diagnosis was made possible by such studies. Cytogeneticists may also contribute to human gene mapping by application of the technique of in situ molecular hybridization. The localization of the immunoglobulin kappa light chain genes (IGKV) to the short arm of chromosome 2 reported at this workshop provides the first example of the localization of an unassigned, unique DNA gene sequence by this method. Combined with the use of chromosomal translocations, resolution of assignments to chromosomal sub-bands is possible, and, as suitable DNA clones become available, the technique should have wide applicability in human gene mapping.

Chromosome Aberrations↗
PubMed1980

Prenatal detection of a probable heterozygote for ADA deficiency and severe combined immunodeficiency disease using a microradioassay.

A pregnancy at risk for adenosine deaminase deficiency and severe combined immunodeficiency disease has been investigated by assay of adenosine deaminase activity in cultured amniotic fluid cells using a microradioassay. A low-normal level of activity consistent with heterozygote status in the foetus was found and confirmed after birth by assay of red cell and fibroblast adenosine deaminase activities. It is suggested that the radioassay method offers significant advantages in sensitivity and specificity over the standard spectrophotometric procedure.

Adenosine Deaminase↗
PubMed1980

Alkaline phosphatase activity of normal and cystic fibrosis fibroblasts.

Alkaline phosphatase (ALP) activities were compared in fibroblasts from three cystic fibrosis patients and two normal controls after culturing the cells in normal growth medium and in medium containing Tamm-Horsfall glycoprotein, isoproterenol, and theophylline. No consistent alterations in ALP activities were noted, either between the same cell lines grown under different conditions, or between normal and cystic cell lines. It is concluded that it is not possible to use changes in ALP activity in cultured cells for the prenatal diagnosis of cystic fibrosis.

Alkaline Phosphatase↗
PubMed1976

Localisation of the human ABO: Np-1: AK-1 linkage group by regional assignment of AK-1 to 9q34.

Quantitative red cell adenylate kinase (AK-1) assay has been used in 8 patients with partial duplication or deletion of chromosome 9 in an attempt to find the precise intrachromosomal location of the structural gene locus. All regions of chromosome 9 are represented in abnormal dosage in at least one patient. A 43% increase in AK-1 activity was found to be associated with duplication of the terminal band of the long arm of chromosome 9. Duplication of all other parts of chromosome 9 were associated with normal enzyme activity. These findings not only confirm the assignment of the AK-1 locus to chromosome 9 made previously in somatic cell hybrids, but suggest a more precise assignment to region 9q33 leads to qter. This places the ABO:Np-1:AK-1 linkage group at the distal end of the long arm of chromosome 9.

ABO Blood-Group System↗