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1.
Br J Cancer ; 98(4): 840-4, 2008 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-18283300

RESUMEN

To evaluate current guidelines criteria for inclusion of women in special 'breast cancer family history' surveillance programmes, records were reviewed of women referred to Scottish breast cancer family clinics between January 1994 and December 2003 but discharged as at 'less than 'moderate' familial risk'. The Scottish Cancer Registry was then interrogated to determine subsequent age-specific incidence of breast cancer in this cohort and corresponding Scottish population figures. Among 2074 women, with an average follow-up of 4.0 years, 28 invasive breast cancers were recorded up to December 2003, where 14.4 were expected, a relative risk (RR) of 1.94. Eleven further breast cancers were recorded between January 2004 and February 2006 (ascertainment incomplete for this period). The overall RR for women in the study cohort exceeded the accepted 'cutoff' level (RR=1.7) for provision of special counselling and surveillance. The highest RR was found for the age group 45-59 years and this group also generated the majority of breast cancers. The National Institute for Clinical Excellence ('NICE') guidelines appear to be more accurate than those of the Scottish Intercollegiate Guidelines Network ('SIGN') in defining 'moderate' familial risk, and longer follow-up of this cohort could generate an evidence base for further modification of familial breast cancer services.


Asunto(s)
Neoplasias de la Mama/epidemiología , Tamizaje Masivo , Adenocarcinoma/epidemiología , Adenocarcinoma/genética , Adulto , Distribución por Edad , Anciano , Neoplasias de la Mama/genética , Carcinoma Ductal de Mama/epidemiología , Carcinoma Ductal de Mama/genética , Carcinoma Lobular/epidemiología , Carcinoma Lobular/genética , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Guías como Asunto , Humanos , Incidencia , Mamografía , Persona de Mediana Edad , Invasividad Neoplásica , Vigilancia de la Población , Pronóstico , Estudios Prospectivos , Factores de Riesgo , Escocia/epidemiología
2.
Brain Res Dev Brain Res ; 130(1): 53-63, 2001 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-11557093

RESUMEN

Flathead is a rat neurological mutant which is phenotypically characterized by a flattened cranium, resting tremor, ataxia, progressive paralysis of the hind limbs, and death at 3-4 weeks after birth. Previous studies showed that rats homozygous for the mutation have a dramatically reduced brain size caused by a burst of apoptosis that begins after embryonic day 16 (E16) and which peaks at about E18. Late-developing structures such as the dentate gyrus, internal granule layer of the cerebellum, and superficial layers of the neocortex are severely depleted of cells. In the present study we have found that neurons and glia are both affected by the mutation. Immunohistochemical analysis with TAG-1, a marker for migratory neurons, revealed reduced staining in Fh neocortex and cerebellum, indicating that the mutation affects neuronal migration or a developmental event prior to it. Analysis of acutely dissociated neocortical cultures showed an accumulation of nestin-positive progenitor cells. Moreover, a substantial proportion of these progenitor cells were multinucleated with the nuclei organized as rosettes. Such multinucleated cells were also found in intact sections of the neocortex and the cerebellum where their presence was restricted to proliferative zones. Within the neocortex, the abundance of multinucleated progenitors is highest at E18 and decreases thereafter, thus correlating with the profile of cell death. This, along with the dramatically higher frequency of apoptosis among multinucleated cells, suggests that the aberrant cell death in Fh is due to defective cytokinesis that occurs in progenitor cells during late stages of brain development.


Asunto(s)
Apoptosis/genética , Moléculas de Adhesión Celular Neuronal , Cerebelo/anomalías , Neocórtex/anomalías , Proteínas del Tejido Nervioso , Neuronas/citología , Células Madre/citología , Animales , División Celular/genética , Cerebelo/patología , Contactina 2 , ADN/biosíntesis , Células Gigantes/química , Células Gigantes/citología , Etiquetado Corte-Fin in Situ , Proteínas de Filamentos Intermediarios/análisis , Glicoproteínas de Membrana/análisis , Neocórtex/patología , Nestina , Neuroglía/citología , Neuronas/química , Ratas , Ratas Mutantes , Cráneo/anomalías , Células Madre/química
3.
Protein Sci ; 10(4): 697-706, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11274460

RESUMEN

In contrast with other animal species, humans possess three distinct genes for class I alcohol dehydrogenase and show polymorphic variation in the ADH1B and ADH1C genes. The three class I alcohol dehydrogenase isoenzymes share approximately 93% sequence identity but differ in their substrate specificity and their developmental expression. We report here the first three-dimensional structures for the ADH1A and ADH1C*2 gene products at 2.5 and 2.0 A, respectively, and the structure of the ADH1B*1 gene product in a binary complex with cofactor at 2.2 A. Not surprisingly, the overall structure of each isoenzyme is highly similar to the others. However, the substitution of Gly for Arg at position 47 in the ADH1A isoenzyme promotes a greater extent of domain closure in the ADH1A isoenzyme, whereas substitution at position 271 may account for the lower turnover rate for the ADH1C*2 isoenzyme relative to its polymorphic variant, ADH1C*1. The substrate-binding pockets of each isoenzyme possess a unique topology that dictates each isoenzyme's distinct but overlapping substrate preferences. ADH1*B1 has the most restrictive substrate-binding site near the catalytic zinc atom, whereas both ADH1A and ADH1C*2 possess amino acid substitutions that correlate with their better efficiency for the oxidation of secondary alcohols. These structures describe the nature of their individual substrate-binding pockets and will improve our understanding of how the metabolism of beverage ethanol affects the normal metabolic processes performed by these isoenzymes.


Asunto(s)
Alcohol Deshidrogenasa/química , Sustitución de Aminoácidos/genética , Cristalografía por Rayos X/métodos , Isoenzimas/química , Polimorfismo Genético/genética , Especificidad por Sustrato/fisiología , Sitios de Unión , Cristalografía por Rayos X/instrumentación , Escherichia coli/genética , Expresión Génica , Humanos , Oxidación-Reducción
5.
Cancer Genet Cytogenet ; 116(2): 105-10, 2000 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-10640141

RESUMEN

Exciting new techniques in molecular cytogenetics--namely, spectral karyotyping, multiplex fluorescence in situ hybridization (M-FISH), and cross species color banding--have been recently developed. An increasing number of reports demonstrate the success of these procedures in providing additional cytogenetic information--identifying marker chromosomes and revealing the presence of previously undetected chromosomal changes. However, these procedures have their limitations, and their absolute sensitivity in the accurate identification of subtle chromosomal abnormalities remains to be established. M-FISH and color banding have been applied to a case of chronic myeloid leukemia with a complex Philadelphia translocation involving chromosomes 9, 17, and 22, which had initially been identified from G-banded chromosome analysis. The abnormalities were confirmed by chromosome "painting" and specific probes. Although M-FISH and color banding revealed no additional cryptic chromosomal changes, this study has clearly demonstrated the success of these multiple color FISH approaches in the accurate characterization of a complex rearrangement with subtle abnormalities.


Asunto(s)
Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Cromosoma Filadelfia , Adolescente , Bandeo Cromosómico , Pintura Cromosómica/métodos , Cromosomas Humanos Par 17 , Colorantes Fluorescentes , Proteínas de Fusión bcr-abl/genética , Humanos , Cariotipificación , Masculino
8.
Singapore Med J ; 40(4): 273-5, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10487083

RESUMEN

We describe a 7-year-old boy presenting with mental retardation and hyperactivity. Clinical features include microcephaly, hypertelorism, epicanthic eye folds and antimongoloid slant. He also has large ears, large hands and feet, and torticollis. The karyotype was 46, XY, r (22) (p13q13). In situ hybridisation studies with a subtelomeric probe for distal 22q confirmed that the ring was deleted causing partial monosomy of 22q.


Asunto(s)
Cromosomas Humanos Par 22 , Discapacidad Intelectual/genética , Monosomía , Cromosomas en Anillo , Anomalías Múltiples/genética , Niño , Humanos , Cariotipificación , Masculino
9.
Am J Med Genet ; 86(3): 289-93, 1999 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-10482883

RESUMEN

We describe an infant girl with an interstitial deletion of chromosome bands 5q33 to 5q35 inherited from a maternal interchromosomal insertion ins(8;5)(p23;q33q35) which was demonstrated by fluorescent in situ hybridization with whole chromosome paints. Physical anomalies included hypertonicity, microcephaly, short neck, apparently low-set ears, micrognathia, camptodactyly, mild rocker bottom feet, and hammer toe. Cardiac anomalies included a large ventricular septal defect, patent ductus arteriosus, pulmonary hypertension and hypoplastic right ventricle. She died at age 3 months.


Asunto(s)
Anomalías Múltiples/genética , Aberraciones Cromosómicas , Deleción Cromosómica , Cromosomas Humanos Par 5/genética , Cromosomas Humanos Par 8/genética , Facies , Femenino , Cardiopatías Congénitas/genética , Humanos , Hibridación Fluorescente in Situ , Lactante , Recién Nacido , Cariotipificación , Síndrome
11.
J Paediatr Child Health ; 35(2): 210-3, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10365364

RESUMEN

We report two female patients with gonadal dysgenesis and sex chromosome mosaicism involving the Y chromosome. Conventional karyotyping was supplemented with fluorescent in situ hybridisation techniques in order to confirm the presence of Y chromosomes. One patient is a phenotypic female with karyotype 45,X/46,X,idic(Y)(q11.2). She underwent a laparoscopic gonadectomy at which streak ovaries without evidence of gonadoblastoma were removed. The second patient presented as a virilised female with karyotype 45,X/47,XYY. At laparoscopy, she was found to have mixed gonadal dysgenesis with a gonadoblastoma in situ. We recommend early gonadectomy in female children presenting with gonadal dysgenesis and the presence of a Y chromosome although once the gonadoblastoma locus on Y chromosome gene has been cloned it may be possible to identify those patients who have a low risk of developing gonadoblastoma.


Asunto(s)
Disgenesia Gonadal/genética , Gonadoblastoma/genética , Neoplasias Ováricas/genética , Aberraciones Cromosómicas Sexuales/genética , Cromosoma Y , Preescolar , Femenino , Estudios de Seguimiento , Gonadoblastoma/diagnóstico , Gonadoblastoma/cirugía , Humanos , Hibridación Fluorescente in Situ , Mosaicismo/genética , Neoplasias Ováricas/diagnóstico , Neoplasias Ováricas/cirugía , Ovariectomía , Medición de Riesgo , Aberraciones Cromosómicas Sexuales/diagnóstico , Resultado del Tratamiento
14.
J Nurs Adm ; 26(7-8): 27-36, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8708792

RESUMEN

Distance learning refers to any educational experience in which the instructor (teacher) is separated from the student (learner) by geographic distance. Partnerships are being established between institutions of higher education and healthcare organizations to achieve a mutual goal, that of educating employees to work in a rapidly changing workplace environment. The authors describe one such partnership and the common issues confronted by both the academic and service institutions in implementing an outreach education program. The authors propose that these partnerships can be effective in implementing distance learning programs that meet the ongoing educational needs of nurses living and working in rural and underserved environments.


Asunto(s)
Redes de Comunicación de Computadores , Educación de Postgrado en Enfermería/organización & administración , Relaciones Interinstitucionales , Modelos Educacionales , Personal de Enfermería/educación , Universidades , Adulto , Estudios de Evaluación como Asunto , Docentes de Enfermería/organización & administración , Humanos , New York , Proyectos Piloto , Servicios de Salud Rural
15.
Clin Nurse Spec ; 9(6): 322-5, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8697377

RESUMEN

CONCEPTS AND ASSUMPTIONS of self-in-relation theory of women's development, as proposed by feminist scholars at the Stone Center in Wellesley, Massachusetts, are applied in this article. This theory was used as a framework to guide staff development and mentorship roles of advanced practice nurses. How the theory served to direct these roles and assisted in development of a professional practice model is discussed. Exemplars from the authors' practices and professional practice outcomes after 2 years of theory implementation are presented.


Asunto(s)
Perfil Laboral , Modelos de Enfermería , Enfermeras Clínicas/psicología , Teoría de Enfermería , Autoimagen , Derechos de la Mujer , Femenino , Humanos , Relaciones Interprofesionales , Mentores , Desarrollo de Personal
16.
Clin Genet ; 47(6): 311-7, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7554365

RESUMEN

Two children presenting with sporadic unilateral retinoblastoma and exhibiting a high degree of chromosome breakage were noted to have unusual facies, microcephaly and abnormal skin pigmentation. In the first child the pattern of both spontaneous and mitomycin-C-induced chromosome breakage was characteristic of Fanconi's anaemia although the degree of breakage was extreme. She also exhibited a striking increase in X-ray-induced chromosomal damage in G0 lymphocytes as measured by dicentric formation and increase in chromatid-type aberrations. She had a number of typical clinical features, including cafe-au-lait patches and abnormalities involving the kidney; however, she demonstrated neither the hypoplasia of radius and thumb nor the typical aplastic phase of this disorder. At age 22 months the child became anaemic with trilineage myelodysplasia, which was rapidly followed by the development of acute myeloblastic leukaemia. The early onset (at age 4 months) of retinoblastoma may have been associated with the underlying genomic instability. The second child exhibited a pattern of chromosome breakage characteristic of Bloom's syndrome, in addition to a moderate increase in damage induced by mytomycin-C. She had the typical stunted growth and malar hypoplasia of Bloom's syndrome although she did not demonstrate the frequently described erythematous 'butterfly rash' Although patients with Fanconi's anaemia and Bloom's syndrome are recognised to be at an increased risk of cancer, retinoblastoma has not previously been described in patients with either condition. We suggest that underlying recessive chromosome breakage syndromes may be underdiagnosed in paediatric cancer patients, with important implications for prognosis and genetic counselling.


Asunto(s)
Síndrome de Bloom/complicaciones , Aberraciones Cromosómicas , Neoplasias del Ojo/genética , Anemia de Fanconi/complicaciones , Retinoblastoma/genética , Síndrome de Bloom/diagnóstico , Síndrome de Bloom/genética , Preescolar , Cromosomas/efectos de los fármacos , Cromosomas/efectos de la radiación , ADN/efectos de los fármacos , ADN/genética , ADN/efectos de la radiación , Anemia de Fanconi/diagnóstico , Anemia de Fanconi/genética , Femenino , Humanos , Lactante , Recién Nacido , Leucemia Mieloide Aguda/etiología , Leucemia Mieloide Aguda/genética , Linfocitos/química , Mitomicina/farmacología , Intercambio de Cromátides Hermanas
17.
Blood ; 85(7): 1742-50, 1995 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-7703482

RESUMEN

Clinical, morphologic, and cytogenetic features were examined in a group of 68 children with myelodysplasia (MDS) referred to a single institution between 1971-1991. The morphologic French-American-British (FAB) system of classification proved of limited value in this group of patients because 50% of the cases were categorized as chronic myelomonocytic leukemia and three patients with eosinophilia and MDS were unclassifiable. Cytogenetic analysis was performed in 63 cases and clonal abnormalities were detected in 55%; the most common chromosome involved was number 7. Modification of the FAB system to incorporate additional diagnostic features such as pretreatment fetal hemoglobin (Hb F) and cytogenetics allowed incorporation of the categories of juvenile chronic myeloid leukemia (JCML) and infantile monosomy 7 syndrome (IMo7). The resulting groups of patients had highly significant differences in survival (P = .00009). The overall 5-year survival for the patients was 31.9% (95% CI 21.7 to 44.1) and factors influencing prognosis included: modified FAB type, platelet count, Hb F level, and cytogenetic complexity. We developed a scoring system ("FPC") where each of the following findings at diagnosis scored one point: HbF greater than 10%, platelets < or = 40 x 10(9)/L, and complex karyotypic changes (two or more clonal structural/numerical abnormalities), which produced groups with highly significant differences, patients with a score of 0 having a 5-year survival of 61.6% (CI 33% to 84%), whereas those with a score of two or three all died within 4 years of diagnosis. The revised classification and scoring system may prove helpful in making treatment choices in pediatric MDS and now needs to be tested prospectively in large scale population-based studies.


Asunto(s)
Síndromes Mielodisplásicos/mortalidad , Índice de Severidad de la Enfermedad , Anomalías Múltiples/mortalidad , Análisis Actuarial , Enfermedad Aguda , Médula Ósea/patología , Niño , Preescolar , Aberraciones Cromosómicas , Enfermedades en Gemelos , Femenino , Humanos , Lactante , Leucemia Mieloide/epidemiología , Leucemia Mieloide/etiología , Leucemia Mielomonocítica Crónica/genética , Leucemia Mielomonocítica Crónica/mortalidad , Masculino , Síndromes Mielodisplásicos/genética , Síndromes Mielodisplásicos/patología , Síndromes Mielodisplásicos/terapia , Linaje , Pronóstico , Análisis de Supervivencia , Resultado del Tratamiento
18.
Leukemia ; 9(1): 102-6, 1995 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7845002

RESUMEN

Fourteen cases of dic(9;12)(p11-13;p11-12) in early B-lineage acute lymphoblastic leukemia (ALL) and other hematological malignancies are reported with a review of the literature. Altogether 36 cases were collected for analysis: ALL at diagnosis (31 cases) or in relapse (one case), chronic myeloid leukemia in lymphoid blast crisis (two cases), T-cell lymphoblastic lymphoma (one case) and T-cell non-Hodgkin's lymphoma (one case). We report the first cases of dic(9;12) with a T-cell phenotype. Dic(9;12) occurs predominantly in B-progenitor ALL of childhood and young adults (age range, 1-47 years, median 12 years) but not of infancy. One or more adverse clinical features, age > 10 years, WBC > 100 x 10(9)/l, pre-B immunophenotype, platelets < 100 x 10(9)/l, were found in over 90% of cases. Additional structural chromosomal changes or trisomy 8 were frequently present. Nevertheless with a median follow-up of 5 years, 29/31 cases (94%) remain in first remission conferring an excellent prognosis to this leukemia. Additional cases are being sought to confirm the prognostic value of this cytogenetic aberration in various hematological malignancies.


Asunto(s)
Cromosomas Humanos Par 12 , Cromosomas Humanos Par 9 , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Translocación Genética , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico
19.
Cancer Genet Cytogenet ; 77(2): 99-105, 1994 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-7954328

RESUMEN

Deletion of 6q is a frequent finding in ovarian carcinoma, which would suggest that this region contains one or more putative tumor suppressor genes. Chromosome 6q abnormalities in six ovarian carcinoma cell lines were analyzed by G-banding and fluorescence in situ hybridization (FISH). Using a variety of probes, including a chromosome 6 paint, a probe specific for the chromosome 6 centromere, and cosmids that map to q24 (cCI6-115), q25 (cCI6-4), q26 (cCI6-91, cCI6-119), and q27 (cCI6-13, cCI6-24, and cCI6-111), abnormalities of 6q were found in three cell lines. In cell line OAW42 (hypotetraploid), the sequences complementary to cCI6-119, cCI6-91, and cCI6-13 probes were lost in two homologues of chromosome 6, which indicates the deletion of genetic material from bands q26-27. The same bands were translocated in cell line PEO1 (hypertriploid). The probes from this region were absent on two copies of chromosome 6, but hybridized to two or three markers. In cell line 59M (hyperdiploid) an interstitial deletion proximal to q24 was detected in one chromosome 6. We conclude that it is very likely that a gene or genes localized in bands 6q26-27, and perhaps in the region proximal to 6q24, play a critical role in the development or progression of ovarian carcinoma.


Asunto(s)
Adenocarcinoma/genética , Aberraciones Cromosómicas , Cromosomas Humanos Par 6 , Cósmidos/genética , Neoplasias Ováricas/genética , Femenino , Humanos , Hibridación Fluorescente in Situ , Cariotipificación , Ploidias , Células Tumorales Cultivadas
20.
Genes Chromosomes Cancer ; 10(4): 244-9, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7522537

RESUMEN

Eight patients with myeloid disorders characterised by a karyotype including apparent monosomy or partial monosomy 7, in the presence of a ring or marker chromosome, were investigated by fluorescence in situ hybridisation (FISH) with a chromosome 7 centromere-specific probe and an Alu-PCR derived chromosome 7 paint. In 4 of 5 cases a ring chromosome was shown to be of chromosome 7 origin; in one of these the apparent ring was shown to consist solely of chromosome 7 centromeric material, and in the fifth case the ring was derived from chromosome 18. In three cases monosomy 7 had arisen during the course of karyotype evolution and was clearly not the primary cytogenetic abnormality. One further case demonstrated fragmentation and cryptic translocation of chromosome 7 material. In the last case a chromosome described as der(l)t(1;7)(p11;p11) was redefined as dic(1;7)(p11;q11). The application of FISH has enabled a more accurate characterisation of chromosome abnormalities, and extended studies of this type may eventually lead to more precise prognostic groups defined by karyotype.


Asunto(s)
Deleción Cromosómica , Cromosomas Humanos Par 7 , Monosomía , Síndromes Mielodisplásicos/genética , Adulto , Anciano , Secuencia de Bases , Niño , Femenino , Humanos , Hibridación Fluorescente in Situ , Cariotipificación , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular
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