RESUMO
Debrisoquin hydroxylation capacity determined as the ratio of debrisoquin to 4-OH-debrisoquin (DMR) in urine after a single oral dose (10 mg) was studied in 52 nuclear families comprising 226 subjects. The relative importance of genetic and environmental factors for DMR was studied by path analysis. There was a significant negative correlation between DMR and coffee intake but no significant correlations between DMR and sex, age, alcohol intake, or smoking habits. Path analysis showed that genetic heritability was 0.79 while cultural heritability was only 0.06. Complex segregation analysis gave evidence for a major locus with incomplete dominance (d = 0.28) between a recessive and an additive gene. The frequency of the major gene was 0.31, allowing an estimate of the frequency of slow hydroxylators in the Swedish population of 9.4%. There was also evidence for a multifactorial component accounting for 14% of the total variation. It was not possible to distinguish between the different genotypes within the rapid hydroxylator phenotype. Our data agree with previous studies in British and German populations showing that two alleles at a major autosomal locus can explain most of the observed variation in DMR. The frequency of slow hydroxylators in Sweden is very similar to that reported in other European studies. The debrisoquin metabolic phenotype seems to be extensively controlled by a monogenic system and not significantly influenced by environmental factors or age.
Assuntos
Debrisoquina/metabolismo , Família , Isoquinolinas/metabolismo , Administração Oral , Adolescente , Adulto , Idoso , Consumo de Bebidas Alcoólicas , Biotransformação , Cromatografia Gasosa , Debrisoquina/urina , Meio Ambiente , Feminino , Genótipo , Humanos , Hidroxilação , Masculino , Pessoa de Meia-Idade , Fenótipo , FumarRESUMO
The results of some family and experimental studies related to psoriasis are summarized. Complex segregation analysis of Lomholt's classical family material of psoriasis from the Faroe Islands gave clear evidence of a major locus (additive gene with a frequency of 0.07) plus a strong polygenic component (genetic heritability 0.87). An analysis of another family material showed complete linkage between the major locus for psoriasis and the HLA region. Treatment of cells with 8-methoxypsoralene plus a small dose of UVA induces monoadducts, some of which appear to remain in the DNA for at least 7 days of post-treatment incubation. These monoadducts can be activated to form DNA cross-links by a second, larger UVA dose. 8-Methoxypsoralene plus UVA-induced DNA cross-links can be modified by a repair process which involves the formation of DNA breaks. This process in not observed in XPA cells.
Assuntos
Terapia PUVA , Fotoquimioterapia , Psoríase/genética , DNA/efeitos da radiação , Reparo do DNA , Ligação Genética , Antígenos HLA/genética , Humanos , Psoríase/tratamento farmacológico , Psoríase/radioterapia , Terapia UltravioletaAssuntos
Transtornos da Audição/complicações , Síndrome de Turner/complicações , Adolescente , Adulto , Fatores Etários , Audiometria , Cefalometria , Criança , Pré-Escolar , Citogenética , Eletroencefalografia , Feminino , Humanos , Lactente , Manifestações Neurológicas , Otite Média/complicações , Testes de Função VestibularAssuntos
Meio Ambiente , Neoplasias/epidemiologia , Ocupações , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Sistema de Registros , SuéciaAssuntos
Anencefalia/diagnóstico , Proteínas Fetais/análise , Disrafismo Espinal/diagnóstico , alfa-Fetoproteínas/análise , Amniocentese , Líquido Amniótico/imunologia , Feminino , Doenças Fetais/imunologia , Idade Gestacional , Humanos , Gravidez , Segundo Trimestre da Gravidez , Diagnóstico Pré-NatalRESUMO
In 2001 the centennial of the first Nobel Prizes is celebrated. This essay, which portrays the Nobel Laureate in Physiology or Medicine in 1906 Don Santiago Ramón y Cajal, should be seen as a contribution to that celebration. The aim of the essay is to present one of the founders of modern neuroscience and greatest scientists of all time, his life history, personality, working methods and driving forces as well as his scientific contributions. The title of the essay "Ideas -- like the white water-lily - flourish only in tranquil waters" is a quotation from Ramón y Cajal which characterizes him very well as a scientist. He was extremely productive, he made fundamental contributions to a number of fields within neurobiology with a very few mistakes, and he did it all by himself.
Assuntos
Neurobiologia/história , História do Século XIX , História do Século XX , Prêmio Nobel , EspanhaRESUMO
A continuous increase in the incidence of Down syndrome in Sweden was noted during 1979-1981. This increase mainly occurred among children of younger mothers and was more pronounced for the males than for the females. There was no evidence of a significant seasonal variation, increased frequency of prematurely born children, or decrease in the number of cases aborted after prenatal diagnosis. An analysis of the whole 15-year period indicates that the incidence of Down syndrome has increased slowly in both sexes, and that there might have been a superimposed cyclic variation limited to the males.