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D F Roberts

Publications and source records attributed to D F Roberts.

At least 55 records · Page 3Linked to original sources
PubMed1987

HLA-A, B, DR and Bf allotypes in patients with idiopathic membranous nephropathy (IMN).

Fifty-five adult biopsy-proven patients with idiopathic membranous nephropathy were examined for HLA-A, B and DR antigens, and for the Bf allotypes. The phenotype frequencies of HLA-DR3 (52 vs. 23%) and HLA-B8 (46 vs. 24%) showed a significant increase in the IMN patient group compared to those of controls from the same region. The supraphenotype in which the combination of DR3-B8 alleles in Bf SS homozygotes occurred was significantly more common in the patient group than in the controls. A subset of six individuals carrying antigens DR3, B8, and common Bf*S alleles was identified, and the clinical course of those patients was found to be significantly worse compared to the rest of the patients. The present results do not support the existing suggestion that the clinical course of these diseases in Caucasians is determined by antigens B18 and the rare Bf allele (Bf*F1). It seems likely that IMN is not a single disease but a renal lesion that can result from several combinations of genetic predisposition and environmental stimuli.

Adult↗
PubMed1987

The relation of parenting style to adolescent school performance.

This article develops and tests a reformation of Baumrind's typology of authoritarian, permissive, and authoritative parenting styles in the context of adolescent school performance. Using a large and diverse sample of San Francisco Bay Area high school students (N = 7,836), we found that both authoritarian and permissive parenting styles were negatively associated with grades, and authoritative parenting was positively associated with grades. Parenting styles generally showed the expected relation to grades across gender, age, parental education, ethnic, and family structure categories. Authoritarian parenting tended to have a stronger association with grades than did the other 2 parenting styles, except among Hispanic males. The full typology best predicted grades among white students. Pure authoritative families (high on authoritative but not high on the other 2 indices) had the highest mean grades, while inconsistent families that combine authoritarian parenting with other parenting styles had the lowest grades.

Achievement↗
PubMed1987

HLA (class 1 antigen) status and cell-mediated immunity in multiple sclerosis.

In vitro lymphocyte proliferation in response to allogeneic pooled cells, phytohaemaglutinin (PHA), and pokeweed mitogen (PWM), was measured in relation to HLA A, B and C status in 67 patients with clinically definite multiple sclerosis and in 67 age- and sex-matched controls. Analysis of covariance taking age into account showed significant effects only for A9 and B12 in controls and B27 and Cw3 in patients, fewer than would be expected by chance. It is concluded that HLA Class 1 status is not an important factor in regulating mitogen responsiveness.

Concanavalin A↗
PubMed1987

Genetic structure and differentiation of human populations.

The concepts of genetic constitution and genetic structure are defined in terms of arrays of gene frequencies, the array and distribution of genotypes, and the distribution of probable ancestral contributions to the gene pool. These concepts can, however, be differentiated. Examples of their application to human populations, to illustrate their descriptive, analytical and epidemiological uses, show that the two concepts help to resolve different types of problems.

Alleles↗
PubMed1986

Oceanic islands--a unique opportunity for medical research.

Island populations have a great deal to offer the medical geneticist, ranging from the curiosity value of their individual diseases to the elucidation of the genetic contribution to aetiologies of specific disorders and the understanding of the complexity of morbidity patterns. In the light of our own experiences, upon which this article is based, we recommend oceanic islands to colleagues as a source of fruitful and rewarding research.

Atlantic Islands↗
PubMed1986

Anthropometry and the biological structure of the Hvar population.

Biological structure of the population of the island of Hvar was investigated by using the data on anthropometric variation among nine village populations; 24 body and 14 head dimensions were analysed from 487 male and 437 female adult subjects. Univariate and multivariate analyses revealed heterogeneity among the populations, which says much for the strength of the isolating factors on the island. Using correlations of anthropometric and geographic distance, the observed patterns of variation among villages were closely related to geography, suggesting migration to be an important factor in the formation of the island's population structure. Populations of the examined villages were further grouped to form the population of the eastern part and the population of the western part of the island, which have an ethnodemographic and sociocultural basis. The analyses revealed heterogeneity between the populations and thus provided evidence to support the hypothesis about the existence of the genetically different groups living in the same biotope.

Adult↗
PubMed1986

High resolution chromosome results in retinoblastoma families.

In three families in the North of England, where retinoblastoma is transmitted, 41 members were studied by high resolution chromosome banding at the 500+ and 900+ levels. None of the 10 affected individuals or their normal relatives showed any deletion in the 13q14 region.

Chromosome Banding↗
PubMed1986

Cell-mediated immunological status in multiple sclerosis patients.

In vitro lymphocyte proliferation in response to allogeneic pooled cells, mitogens (PHA, Con A and PWM), and PPD was measured in 67 patients with clinically definite MS and in 67 age and sex-matched controls. Overall, dose-response curves in the two groups were similar, but response to PHA and PWM was significantly greater among patients, and a greater percentage of patients failed to respond to peak and suboptimal PPD concentrations. There was a reduced response to allogeneic pooled cells in Dw2 positive controls, and, in both patients and controls, a tendency towards a higher PPD response in Dw2 positive males. The results suggest that there is some alteration of balance of immune regulation in MS, which is slightly affected by Dw2 status.

Adolescent↗
PubMed1986

Immunogenetic studies in retinoblastoma.

In three unrelated families with transmitted retinoblastoma 43 members were tested for HLA-A, B, C, and DR antigens. On 18 patients, 16 unaffected relatives, and 16 controls, mixed lymphocyte cultures were carried out and the response to mitogens, phytohaemagglutinin, concanavalin A, and pokeweed mitogen examined. There were no associations of retinoblastoma with any HLA antigen. A reduction in T cell function is suggested by the results of the mitogen tests.

Eye Neoplasms↗
PubMed1986

Differentiation of heterozygotes in recessive albinism.

Skin pigmentation was measured by reflectance spectrophotometry in 43 albinos, 44 of their relatives, and 123 random controls among Swazi subjects in southern Africa. Mean reflectance of the subject groups diminishes in the sequence affected subjects, obligate heterozygotes, other unaffected family members, random subjects, and the differences among the unaffected groups are highly significant. A discriminant function fitted to the obligate heterozygotes and random subjects is significant statistically but is not efficient enough to be applied in the diagnosis of the non-carrier state.

Albinism↗
PubMed1986

C3 variants and disease.

The distribution of C3 variants in dermatitis herpetiformis, thyroid cancer, spinal muscular atrophy, multiple sclerosis and psoriasis was studied, and also the Bf phenotype distribution in thyroid cancer. In thyroid cancer there was a significant deficit of heterozygotes for the C3 locus, a possible decrease in the C3F allele frequency and a significant elevation of frequency of the BfF allele. The possible involvement of these alleles in susceptibility to thyroid cancer appears worth further examination.

Alleles↗
PubMed1986

Genetic differentiation among Iranian Christian communities.

From some 500 members of Christian communities in Iran (Armenians and Assyrians from six localities), blood specimens were obtained and examined for a number of blood group, red cell enzyme, and serum protein systems. The results indicate the relatively closed nature of the Christian community as a whole but that moderate differentiation has already occurred among the local groups. One factor in this diversification process that can be distinguished is the effect of urbanization in Tehran, but otherwise it seems to be largely random.

Blood Group Antigens↗
PubMed1986

Karyotype abnormalities in non-Hodgkin lymphomas.

Karyotype anomalies were found in 9 of 13 non-Hodgkin lymphomas. The observed non-random involvement of chromosomes was non-specific and was associated with chromosome breakpoints rather than recurrent markers. The recurrent markers which were found were similar to those of previously published studies. An attempt to correlate histological classification and chromosome anomalies in published series indicated that there were limited histological associations, the frequency of abnormalities of chromosomes 14 and 18 showing the largest disparity between disease types. Among the breakpoints and translocations found are those known to be associated with oncogene location, and the possibility is raised of an oncogene on 18.

Chromosome Aberrations↗