RESUMEN
We have cloned and sequenced the gene encoding a novel ubiquitin-conjugating enzyme in Saccharomyces cerevisiae. Disruption of this gene shows that it is not essential for cell viability.
Asunto(s)
Proteínas Portadoras/genética , Proteínas Fúngicas/genética , Ligasas/genética , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Enzimas Ubiquitina-Conjugadoras , Ubiquitinas/metabolismo , Secuencia de Aminoácidos , Secuencia de Bases , Proteínas Portadoras/metabolismo , ADN de Hongos , Proteínas Fúngicas/metabolismo , Genes Fúngicos , Ligasas/metabolismo , Datos de Secuencia Molecular , Mapeo Restrictivo , Saccharomyces cerevisiae/enzimología , Homología de Secuencia de AminoácidoRESUMEN
Mutations in the MSS1 gene render the yeast cells respiratory deficient only in the presence of the PR454 mutation (paromomycin resistance) in the mitochondrial 15 S ribosomal RNA gene. The MSS1 gene product works in association with the small subunit of mitoribosomes and seems to play some part in mitochondrial translation. The block in the splicing of introns of cytochrome c oxidase subunit 1 could result from a specific impeding of the translation of maturases. Comparison of the MSS1 putative protein with data libraries revealed that it contains, in its second half, the consensus sequences characteristic of GTP binding proteins and is very homologous to the bacterial "genes 50K".
Asunto(s)
Complejo IV de Transporte de Electrones/genética , Proteínas Fúngicas/genética , GTP Fosfohidrolasas/genética , Proteínas de Unión al GTP/genética , Regulación Fúngica de la Expresión Génica , Genes Fúngicos , Mitocondrias/fisiología , Proteínas de Saccharomyces cerevisiae , Secuencia de Bases , ADN Mitocondrial/genética , Proteínas de Unión al GTP/química , Datos de Secuencia Molecular , Conformación de Ácido Nucleico , Paromomicina/farmacología , Biosíntesis de Proteínas , Empalme del ARN , ARN Ribosómico/ultraestructura , Mapeo Restrictivo , Saccharomyces cerevisiae/genética , Alineación de SecuenciaRESUMEN
The use of probes detecting polymorphic loci within the human population has enabled accurate localization of the genetic defect responsible for familial adenomatous polyposis on chromosome 5. This was used to screen two families for the presymptomatic diagnosis in children of an affected parent. In both cases, the use of 8 polymorphic probes located on either side of the gene provided information which could be used in the management of children born from the patients at risk. The set of probes used in this work should be informative in most of the affected adenomatous polyposis families.
Asunto(s)
Poliposis Adenomatosa del Colon/diagnóstico , Aberraciones Cromosómicas/genética , Poliposis Adenomatosa del Colon/genética , Trastornos de los Cromosomas , Mapeo Cromosómico , Cromosomas Humanos Par 5 , Femenino , Marcadores Genéticos/genética , Haplotipos/genética , Humanos , Masculino , Embarazo , Recombinación GenéticaRESUMEN
In order to specify the frequency and the potential consequences of drug interactions in the elderly, we retrospectively analysed 409 discharge prescriptions. The possibility of drug interactions was screened out for each prescription in the software version of the Vidal drug compendium. It appears that prescriptions are mainly adapted to the elderly with respect to posology and pharmacokinetics. Potentially dangerous drug interactions ('contraindicated' or 'unsuitable' associations) were found in 6 per cent of prescriptions; after careful assessment, this frequency decreased to less than 1 per cent. The most common orthoergic side effects were sedation (15 per cent) and hypotension (14.5 per cent). This study points out the multiplicity of criteria to be considered in order to prevent drug interactions, and the gaps in available software.
Asunto(s)
Interacciones Farmacológicas , Prescripciones de Medicamentos/estadística & datos numéricos , Servicios de Salud para Ancianos , Anciano , Anciano de 80 o más Años , Contraindicaciones , Femenino , Francia , Hospitales Especializados/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Preparaciones Farmacéuticas/clasificaciónAsunto(s)
Fibroínas , Proteínas de Insectos , Péptidos , Alanina , Animales , Betaína , Bombyx , Cristalización , Sustancias Macromoleculares , Polímeros , Conformación Proteica , Proteínas , SedaRESUMEN
The nucleotide sequence of a 5 kb EcoRI-NcoI fragment of chromosome IV, contiguous to gene POL3 (CDC2), has been determined. It contains three open reading frames: QRI1, QRI2 and QRI7. Two of them are essential genes. QRI7 is homologous to the Escherichia coli orfx gene.
Asunto(s)
Cromosomas Fúngicos , ADN Polimerasa Dirigida por ADN/genética , Proteínas Fúngicas/genética , Proteínas de Homeodominio , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Transactivadores/genética , Secuencia de Aminoácidos , ADN Polimerasa III , Datos de Secuencia Molecular , Sistemas de Lectura AbiertaRESUMEN
We describe a simple method for characterizing a frequent polymorphism (that substitutes an arginine for a proline) in the coding sequence of the Tp53 gene in patients with colonic cancer and in a control population. We could find no evidence that this polymorphism is associated with a marked predisposition to colorectal cancer.
Asunto(s)
Neoplasias del Colon/genética , Polimorfismo Genético , Neoplasias del Recto/genética , Proteína p53 Supresora de Tumor/genética , Secuencia de Bases , Frecuencia de los Genes , Tamización de Portadores Genéticos , Humanos , Datos de Secuencia Molecular , Sondas de Oligonucleótidos , Reacción en Cadena de la Polimerasa , Valores de ReferenciaRESUMEN
BACKGROUND: Sex-specific issues have not been extensively addressed in studies of HIV prevalence, despite the strong implications of differences between men and women in the risk of HIV transmission. The objective of this study was to examine sex-specific behaviours associated with HIV infection among injection drug users in Montreal. METHODS: A total of 2741 active drug users (2209 [80.6%] men) were recruited between 1988 and 1998. Information was sought on sociodemographic characteristics, drug-related behaviour and sexual behaviour, and participants were tested for HIV antibodies. Sex-specific independent predictors of HIV prevalence were assessed by stepwise logistic regression. RESULTS: The overall prevalence of HIV among study subjects was 11.1%; the prevalence was 12.0% among men and 7.5% among women. In multivariate models, a history of sharing syringes with a known seropositive partner (odds ratio [OR] for men 2.44, 95% confidence interval [CI] 1.72-3.46; OR for women 3.03, 95% CI 1.29-7.13) and of sharing syringes in the past 6 months (OR for men 0.61, 95% CI 0.44-0.85; OR for women 0.32, 95% CI 0.14-0.73) were independently associated with HIV infection. Other variables associated with HIV infection were homosexual or bisexual orientation, cocaine rather than heroin as drug of choice, frequency of injection drug use, and obtaining needles at a pharmacy or through needle exchange programs (for men only) and obtaining needles at shooting galleries and being out of treatment (for women only). INTERPRETATION: These results support the hypothesis that risk factors for HIV seropositivity differ between men and women. These sex-related differences should be taken into account in the development of preventive and clinical interventions.
Asunto(s)
Infecciones por VIH/transmisión , Drogas Ilícitas , Abuso de Sustancias por Vía Intravenosa/epidemiología , Adolescente , Adulto , Bisexualidad/estadística & datos numéricos , Intervalos de Confianza , Estudios Transversales , Femenino , Infecciones por VIH/epidemiología , Homosexualidad Masculina/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Compartición de Agujas/estadística & datos numéricos , Quebec/epidemiología , Factores de Riesgo , Sexo Seguro , Factores SexualesRESUMEN
The EF5.44 locus is in close proximity to the chromosome 5 region to which the genetic defect responsible for familial adenomatous polyposis has been mapped. We have devised two oligonucleotides that promote the specific polymerase chain reaction (PCR) amplification of a 365-bp sequence in this region. Analysis by denaturing gradient gel electrophoresis of the resulting fragment has unravelled individual differences that could be identified as a single base pair change in a MnlI restriction site. This PCR assayable polymorphism increases the informativeness at this locus, and should be useful in the presymptomatic diagnosis of familial adenomatous polyposis.
Asunto(s)
Poliposis Adenomatosa del Colon/genética , Cromosomas Humanos Par 5 , Ligamiento Genético , Polimorfismo Genético , Secuencia de Bases , ADN , Electroforesis en Gel de Poliacrilamida , Femenino , Humanos , Masculino , Datos de Secuencia Molecular , Linaje , Reacción en Cadena de la PolimerasaRESUMEN
Familial adenomatous polyposis is a rare disease inherited in a Mendelian dominant fashion. It is characterized by the occurrence of more than 100 adenomatous polyps in the large bowels of affected individuals. The genetic defect responsible for adenomatous polyposis resides at a locus called APC which has been localized to the long arm of human chromosome 5. In this study, the APC locus was mapped with respect to 11 markers known to map to this chromosomal segment. Linkage of APC to four of these markers had been previously reported. Three additional markers are shown here to be linked to APC. By multipoint analysis, the APC locus maps to an interval bounded by D5S49 and D5S58. The refined map of the APC locus and the new markers described here improve the informativeness and accuracy of the presymptomatic diagnosis of familial adenomatous polyposis.