RESUMEN
We examined a panel of sporadic breast carcinomas for loss of heterozygosity (LOH) in a 10-cM interval on chromosome 10 known to encompass the PTEN gene. We detected allele loss in 27 of 70 breast tumour DNAs. Fifteen of these showed loss limited to a subregion of the area studied. The most commonly deleted region was flanked by D10S215 and D10S541 and encompasses the PTEN locus. We used a combination of denaturing gradient gel electrophoresis and single-strand conformation polymorphism analyses to investigate the presence of PTEN mutations in tumours with LOH in this region. We did not detect mutations of PTEN in any of these tumours. Our data show that, in sporadic breast carcinoma, loss of heterozygosity of the PTEN locus is frequent, but mutation of PTEN is not. These results are consistent with loss of another unidentified tumour suppressor in this region in sporadic breast carcinoma.
Asunto(s)
Neoplasias de la Mama/genética , Cromosomas Humanos Par 10 , Genes Supresores de Tumor , Pérdida de Heterocigocidad , Monoéster Fosfórico Hidrolasas/genética , Polimorfismo Conformacional Retorcido-Simple , Proteínas Supresoras de Tumor , Centrómero/genética , Mapeo Cromosómico , ADN de Neoplasias/genética , Femenino , Humanos , Repeticiones de Microsatélite , Fosfohidrolasa PTEN , Reacción en Cadena de la PolimerasaRESUMEN
The non-toxic binding fragment of tetanus toxin (fragment C) binds avidly to neural tissue and has a growing number of neurobiological uses. Its current utility is limited by both its high commercial cost and the complex procedure for its preparation requiring highly purified tetanus toxin. We have developed a short procedure which prepares fragments of tetanus toxin from crude C. tetani extracts. The resultant proteins are atoxic with molecular sizes and immunological properties closely resembling fragment C. These proteins undergo retrograde axonal and apparent transneuronal transport in a fashion similar to fragment C.
Asunto(s)
Bloqueantes Neuromusculares/química , Fragmentos de Péptidos/química , Toxina Tetánica/química , Animales , Anticuerpos Monoclonales/inmunología , Antígenos/inmunología , Transporte Axonal , Clostridium tetani , Electroforesis en Gel de Poliacrilamida , Nervio Hipogloso/anatomía & histología , Immunoblotting , Inmunohistoquímica , Técnicas In Vitro , Ratones , Peso Molecular , Bloqueantes Neuromusculares/inmunología , Bloqueantes Neuromusculares/metabolismo , Neuronas/metabolismo , Fragmentos de Péptidos/inmunología , Fragmentos de Péptidos/metabolismo , Toxina Tetánica/inmunología , Toxina Tetánica/metabolismoRESUMEN
Single-dose immunization against tetanus was studied in 511 previously non-immunized residents of rural villages in Upper Volta. Males and females were equally represented and a wide age range was covered. A single dose of adsorbed tetanus toxoid containing 17.5 Lf units of toxoid and 3.86 mg of aluminium phosphate per 0.5 ml dose was used. Blood samples were taken 7 days, 2 months, and 12 months after immunization, and serum antitoxin titres were determined by neutralization titrations in mice. Adverse reactions were negligible. Only 2 participants gave evidence of prior immunization by developing detectable antitoxin titres after 7 days; they were eliminated from the study. After 12 months, 59% of the participants had antitoxin titres of >/=0.01 IU/ml, a titre usually considered protective. The mean titre and the proportion of those protected decreased substantially with increasing age; overall, females gave somewhat greater serological responses than males. Mean titre increased by 25% between 2 months and 1 year after immunization; the increase was greater in females than in males. In children under 6 years of age, 100% of females and 82% of males had protective titres after 1 year.
Asunto(s)
Toxoide Tetánico/inmunología , Adolescente , Animales , Niño , Femenino , Humanos , Lactante , Masculino , Ratones , Pruebas Serológicas , Factores Sexuales , Tétanos/inmunología , Tétanos/prevención & control , Antitoxina Tetánica/análisis , Toxoide Tetánico/administración & dosificaciónAsunto(s)
Suero Antilinfocítico , Trasplante de Piel , Animales , Formación de Anticuerpos , Suero Antilinfocítico/administración & dosificación , Membrana Basal/inmunología , Femenino , Técnica del Anticuerpo Fluorescente , Haplorrinos , Caballos/inmunología , Humanos , Reacción de Inmunoadherencia , Inmunoglobulina G/análisis , Inyecciones Intravenosas , Inyecciones Subcutáneas , Glomérulos Renales/inmunología , Linfocitos/inmunología , Macaca/inmunología , Masculino , Trasplante HomólogoAsunto(s)
Suero Antilinfocítico/normas , Animales , Suero Antilinfocítico/administración & dosificación , Suero Antilinfocítico/aislamiento & purificación , Perros , Rechazo de Injerto , Caballos , Inmunoglobulina G/análisis , Inmunoglobulinas/aislamiento & purificación , Inmunoglobulinas/normas , Terapia de Inmunosupresión , Inyecciones Subcutáneas , Trasplante de Riñón , Factores de Tiempo , Supervivencia Tisular , Trasplante HomólogoRESUMEN
Sephadex gel filtration can be employed as a preparative procedure for the purification of both tetanus and diphtheria toxoids. A toxoid purification sequence is described in the text. By utilizing the described methods and columns, up to 100,000 human doses of diphtheria toxoid could be processed in a single operation. The method has given an 80% yield of diphtheria toxoid with a purity of 1,900 Lf per mg of N. The analysis of the material by immunodiffusion tests showed that a marked increase in purity was achieved. Antigenicity tests demonstrated that there was no significant difference in antigenic potency between the parent toxoid and its purified fraction. Factors limiting the effective separation of tetanus toxoid by gel filtration are discussed. The construction of the columns used is described in detail, as well as packing procedures and column characteristics such as bed volume, void volume, sample size, and flow rate.