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2.
Actas dermo-sifiliogr. (Ed. impr.) ; 92(10): 461-464, oct. 2001. ilus
Artigo em Es | IBECS | ID: ibc-970

RESUMO

La aplasia cutánea congénita es un grupo heterogéneo de trastornos en los que áreas más o menos extensas de piel están ausentes al nacer. Fue descrito por Cordon en 1767. Aunque la mayoría de casos son esporádicos, están descritos casos familiares con herencia autosómica dominante o recesiva con expresividad variable. La aplasia cutánea puede aparecer de forma aislada o asociada a otras malformaciones, y se han propuesto varias clasificaciones según el tipo de herencia, la localización del defecto y las anomalías asociadas. Presentamos un caso localizado en el cuero cabelludo, sin otras anomalías asociadas, con otros tres miembros de la familia afectos, correspondiendo a una herencia autosómica dominante (AU)


Assuntos
Feminino , Lactente , Humanos , Couro Cabeludo/lesões , Couro Cabeludo/patologia , Displasia Ectodérmica/diagnóstico , Displasia Ectodérmica/terapia , Displasia Ectodérmica/mortalidade , Aberrações Cromossômicas/diagnóstico , Aberrações Cromossômicas/etiologia , Displasia Ectodérmica/classificação , Displasia Ectodérmica/genética , Teratógenos , Dermatopatias/congênito
3.
Fertil Steril ; 76(2): 249-53, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11476768

RESUMO

OBJECTIVE: To compare the karyotype of babies conceived through ICSI with that of naturally conceived babies. DESIGN: Prospective controlled study. SETTING: The Egyptian IVF-ET Center, Cairo, Egypt. PATIENT(S): Four hundred and thirty babies conceived through ICSI and 430 babies conceived naturally. INTERVENTION(S): ICSI and karyotyping. MAIN OUTCOME MEASURE(S): Abnormal karyotype. RESULT(S): Four hundred and thirty consecutive babies conceived through ICSI who were delivered in one hospital had 15 abnormal karyotypes (3.5%). Of the 15 babies, 7 were of female phenotype and 8 of male phenotype. Six babies had sex chromosome anomalies, 8 had autosomal anomalies, and 1 had combined sex chromosome and autosomal anomalies. A control group of 430 consecutive babies conceived naturally who were delivered in one hospital had no abnormal karyotype. The difference between the two groups was significant (P<.001). CONCLUSION(S): ICSI carries a small but significant increased risk of abnormal karyotyping to the offspring. This risk appears to be equally distributed between autosomal and sex chromosome anomalies.


Assuntos
Aberrações Cromossômicas/etiologia , Injeções de Esperma Intracitoplásmicas/efeitos adversos , Adulto , Aberrações Cromossômicas/genética , Transtornos Cromossômicos , Egito , Feminino , Humanos , Recém-Nascido , Cariotipagem , Masculino , Pessoa de Meia-Idade , Gravidez , Estudos Prospectivos , Aberrações dos Cromossomos Sexuais/etiologia
5.
Chromosome Res ; 9(3): 235-42, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11330398

RESUMO

Robertsonian translocations (ROBs) are the most common rearrangements in humans, contributing significantly to genetic imbalance, fetal wastage, mental retardation and birth defects. Rob(14q21q) and rob(13q14q), which are formed predominantly during female meiosis, comprise the majority (approximately 85%) of all ROBs. Previous studies have shown that the breakpoints are consistently located within specific regions of the proximal short arms of chromosomes 13, 14, and 21. The high prevalence of these translocations, the consistent breakpoints found, and the fact that roughly 50% of cases occur sporadically suggest that the sequences at or near the breakpoints confer susceptibility to chromosome rearrangement and that the rearrangements occur through a specific mechanism. To investigate this hypothesis, we developed hamster-human somatic cell hybrids derived from de novo rob(14q21q) patients that contained the translocated chromosome segregated from the other acrocentric chromosomes. We determined the physical order of five satellite III subfamilies on 14p, and investigated their involvement in formation of these de novo translocations.


Assuntos
Anormalidades Múltiplas/genética , Aberrações Cromossômicas/genética , Cromossomos Humanos Par 14/genética , DNA Satélite , Translocação Genética/genética , Anormalidades Múltiplas/etiologia , Aneuploidia , Aberrações Cromossômicas/etiologia , Transtornos Cromossômicos , Cromossomos Humanos Par 21/genética , Síndrome de Down/etiologia , Síndrome de Down/genética , Rearranjo Gênico , Humanos , Cariotipagem , Pais , Trissomia
6.
Chromosome Res ; 9(3): 223-33, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11330397

RESUMO

The centromeres and the short arms of the five pairs of acrocentric chromosomes in humans are composed of tandemly ordered repetitive DNA. Previous studies have suggested that the exchanges between acrocentric chromosomes have resulted in concerted evolution of different DNA sequences in their short arms. The acrocentric chromosomes are clinically relevant since they are involved in Robertsonian translocation formation and non-disjunction resulting in aneuploidy. Here we have identified seven new satellite III repetitive DNA subfamilies, determined their nucleotide sequences and established their chromosomal distributions on the short arms of the acrocentric chromosomes. Knowledge of these related sequences may help to elucidate the molecular basis of Robertsonian translocation formation.


Assuntos
Aberrações Cromossômicas/etiologia , Cromossomos Humanos/genética , DNA Satélite/classificação , Sequência de Bases , Transtornos Cromossômicos , Segregação de Cromossomos , Cromossomos Humanos/ultraestrutura , Evolução Molecular , Humanos , Dados de Sequência Molecular , Homologia de Sequência do Ácido Nucleico , Translocação Genética
7.
Isr Med Assoc J ; 3(3): 178-83, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11303374

RESUMO

BACKGROUND: Congenital subependymal pseudocysts are incidental findings that are found in 0.5-5.2% of neonates during postmortem examination or head ultrasonography. In our institution we detected 10 neonates with CSEPC. OBJECTIVE: To investigate associated etiological factors, morphologic characteristics and outcome of CSEPC. METHODS: We performed a meta-analysis of the literature on CSEPC (1967-98), including our 10 cases. RESULTS: A total of 256 cases of CSEPC were analyzed. Ultrasound diagnosed 77.6% of CSEPC; 48.8% were bilateral and 53.4% were located in the caudothalamic groove or head of caudate nucleus. Altogether, 93.5% resolved during 1-12 months of ultrasonographic follow-up. Compared to the general neonatal population, the following features were more prevalent in the CSEPC population: prematurity, maternal vaginal bleeding, preeclamptic toxemia, intrauterine growth restriction, asphyxia, fetal cytomegalovirus and rubella infections, congenital malformations, chromosomal aberrations, infant mortality, and neurodevelopmental handicap. The risk for neurodevelopmental handicap was significantly higher when CSEPC were associated with fetal infections, IUGR, malformations and chromosomal aberrations, or persistence of CSEPC during follow-up. CSEPC infants without any of these four conditions had a low risk for neurodevelopmental handicap. CONCLUSIONS: CSEPC are morphologic features of various underlying conditions encountered in the fetus. Association of CSEPC with IUGR, fetal infections, malformations and chromosomal aberrations or persistence of CSEPC indicates a higher risk for future neurodevelopmental handicaps, probably because of the deleterious effects on the fetal brain that are inherent in these conditions. A favorable outcome is expected in the absence of these risk factors.


Assuntos
Neoplasias Encefálicas/congênito , Neoplasias Encefálicas/diagnóstico por imagem , Cistos/congênito , Cistos/diagnóstico por imagem , Epêndima , Asfixia Neonatal/etiologia , Peso ao Nascer , Neoplasias Encefálicas/complicações , Aberrações Cromossômicas/etiologia , Transtornos Cromossômicos , Cistos/complicações , Deficiências do Desenvolvimento/etiologia , Feminino , Retardo do Crescimento Fetal/etiologia , Ruptura Prematura de Membranas Fetais/etiologia , Idade Gestacional , Humanos , Incidência , Mortalidade Infantil , Recém-Nascido , Masculino , Pré-Eclâmpsia/etiologia , Gravidez , Prognóstico , Estudos Prospectivos , Fatores de Risco , Ultrassonografia
10.
Am J Perinatol ; 17(5): 229-32, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11110338

RESUMO

The objective to characterize neonatal outcome associated with ultrasonographic identification of a single umbilical artery. Pregnancies diagnosed with single umbilical artery antenatally were identified. All prenatal/antenatal and pediatric records were reviewed for maternal demographics, associated anomalies, karyotypic analysis, pregnancy complications, and neonatal outcome. Twenty-seven pregnancies complicated by fetal single umbilical artery were identified. Of the 27 pregnancies, 5 (18.5%) underwent pregnancy termination and 1 (3.7%) experienced fetal demise. Of the 21 liveborn infants, 4 (19%) died within the first year of life. Sixty-seven percent of fetuses had an associated structural anomaly. Sixteen of the 27 pregnancies underwent amniocentesis and 7 of these were chromosomally abnormal. All of the karyotypically abnormal fetuses had a structural defect in addition to the single umbilical artery. Of the six fetuses without any associated structural or chromosomal anomalies, three (50%) demonstrated growth restriction. Single umbilical artery is relatively rare finding. When a single umbilical artery is identified, a vigilant search for associated anomalies should be undertaken. Pregnancies identified as having fetuses with associated structural anomalies should be offered amniocentesis. Pregnancies with isolated single umbilical artery should be carefully monitored for evidence of fetal growth restriction.


Assuntos
Aberrações Cromossômicas/etiologia , Retardo do Crescimento Fetal/etiologia , Complicações na Gravidez , Artérias Umbilicais/anormalidades , Adulto , Aberrações Cromossômicas/genética , Transtornos Cromossômicos , Feminino , Humanos , Recém-Nascido , Cariotipagem , Gravidez , Estudos Retrospectivos , Ultrassonografia Pré-Natal , Artérias Umbilicais/diagnóstico por imagem
11.
Med Tr Prom Ekol ; (8): 16-20, 2000.
Artigo em Russo | MEDLINE | ID: mdl-11019542

RESUMO

The article represents results of long cytogenetic survey among liquidators of Chernobyl accident. The parameters studied are frequency of unstable chromosomal aberrations and frequency of symmetrical translocations. The authors show that, in spite of long term after irradiation, average frequency of cells with dicentrics and centric fusions (unstable chromosomal aberrations) remains relatively high. Discussion includes possible use of cytogenetic methods in reconstruction of absorbed radiation doses in many years after exposure.


Assuntos
Aberrações Cromossômicas/diagnóstico , Lesões por Radiação/diagnóstico , Liberação Nociva de Radioativos , Aberrações Cromossômicas/etiologia , Transtornos Cromossômicos , Citogenética/métodos , Exposição Ambiental/efeitos adversos , Humanos , Hibridização In Situ , Lesões por Radiação/complicações , Ucrânia
12.
Genes Chromosomes Cancer ; 29(3): 266-75, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10992301

RESUMO

It is believed that two important factors in the genesis of reciprocal chromosomal translocations in malignant cells are the physical proximity of the involved regions and local structural features of the chromatin fiber that make them more susceptible to breakage and rearrangement. In this work we sought to investigate whether PML-RARA fusion transcripts, characteristic of acute promyelocytic leukemia (APL), could be induced by a clastogenic agent in cells known to have, a priori, a favorable spatial distribution of these genes. A lymphoid-cell line, lacking the t(15;17) but having the PML and RARA genes in close proximity in specific phases of the cell cycle, was irradiated with 10 Gy of (60)Co, and the incidence of PML-RARA transcripts was analyzed by a highly sensitive PCR assay. Despite gene proximity, typical PML-RARA transcripts were only rarely detected in irradiated cells. The same phenomenon was observed at similar frequency in control non-irradiated cells. These findings made us investigate whether such transcripts could also be detected in peripheral blood cells from normal individuals. PML-RARA transcripts were observed at low frequencies in isolated lymphoid and granulocytic cell populations, with similar incidence in both cell types. The data thus indicate that the PML and RARA genes are not particularly susceptible to the clastogenic effects of gamma-irradiation, and that, similar to what has been reported for other chromosomal translocations, transcriptionally active PML-RARA rearrangements can be generated in normal hematopoietic cells of different lineages without apparent oncogenic consequences.


Assuntos
Células-Tronco Hematopoéticas/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/efeitos da radiação , Proteínas Nucleares , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/efeitos da radiação , Receptores do Ácido Retinoico/genética , Receptores do Ácido Retinoico/efeitos da radiação , Fatores de Transcrição/genética , Fatores de Transcrição/efeitos da radiação , Aberrações Cromossômicas/etiologia , Transtornos Cromossômicos , Raios gama/efeitos adversos , Células-Tronco Hematopoéticas/efeitos da radiação , Humanos , Leucemia Promielocítica Aguda/genética , Leucemia Promielocítica Aguda/metabolismo , Mutação , Proteína da Leucemia Promielocítica , Recombinação Genética/efeitos da radiação , Receptor alfa de Ácido Retinoico , Células Tumorais Cultivadas/metabolismo , Células Tumorais Cultivadas/efeitos da radiação , Proteínas Supressoras de Tumor
14.
Genes Chromosomes Cancer ; 28(3): 329-36, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10862039

RESUMO

The comparative genomic hybridization technique (CGH) was used to identify common chromosomal imbalances in osteosarcomas (OS), which frequently display complex karyotypic changes. We analyzed 13 high-grade primary tumors, 5 corresponding cell lines, 2 primary tumors grade 2, and 1 recurrent tumor from a total of 16 patients. Some of the CGH results have been verified by fluorescence in situ hybridization (FISH) studies. Gains of chromosomal material were more frequent than losses. Most common gains were observed at 8q (11 cases), 4q (9 cases), 7q (8 cases), 5p (7 cases), and 1p (8 cases). The smallest regions of overlap have been narrowed down to 8q23 (10 cases), 4q12-13 (8 cases), 5p13-14 (7 cases), 7q31-32 (7 cases), 8q21 (7 cases), and 4q28-31 (5 cases). These data demonstrate that a number of chromosomal regions and even two distinct loci on 4q and 8q are involved in the pathogenesis of OS, with gain of 4q12-13 chromosomal material representing a newly identified locus. Seven of 16 cases displayed, besides gain of 8q23 sequences, gain of MYC copies in CGH and FISH. Previous CGH reports confined gain of 8q material to 8cen-q13, 8q21.3-8q22, and 8q23-qter, whereas our data suggest that the loci 8q21 and 8q23-24 are affected in the development of OS. In contrast to recent reports, copy number increases at 8q and 1q21 did not have an unfavorable impact on prognosis in the present series. Genes Chromosomes Cancer 28:329-336, 2000.


Assuntos
Neoplasias Ósseas/etiologia , Neoplasias Ósseas/genética , Aberrações Cromossômicas/etiologia , Aberrações Cromossômicas/genética , Osteossarcoma/etiologia , Osteossarcoma/genética , Adolescente , Adulto , Criança , Transtornos Cromossômicos , Coloração Cromossômica , Feminino , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Masculino , Hibridização de Ácido Nucleico
15.
Arch Dis Child ; 82(5): 349-52, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10799420

RESUMO

AIMS: To investigate socioeconomic inequalities in the risk of congenital anomalies, focusing on risk of specific anomaly subgroups. METHODS: A total of 858 cases of congenital anomaly and 1764 non-malformed control births were collected between 1986 and 1993 from four UK congenital malformation registers, for the purposes of a European multicentre case control study on congenital anomaly risk near hazardous waste landfill sites. As a measure of socioeconomic status, cases and controls were given a value for the area level Carstairs deprivation index, by linking the postcode of residence at birth to census enumeration districts (areas of approximately 150 households). RESULTS: Risk of non-chromosomal anomalies increased with increasing socioeconomic deprivation. The risk in the most deprived quintile of the deprivation index was 40% higher than in the most affluent quintile. Some malformation subgroups also showed increasing risk with increasing deprivation: all cardiac defects, malformations of the cardiac septa, malformations of the digestive system, and multiple malformations. No evidence for socioeconomic variation was found for other non-chromosomal malformation groups, including neural tube defects and oral clefts. A decreasing risk with increasing deprivation found for all chromosomal malformations and Down's syndrome in unadjusted analyses, occurred mainly as a result of differences in the maternal age distribution between social classes. CONCLUSION: Our data, although based on limited numbers of cases and geographical coverage, suggest that more deprived populations have a higher risk of congenital anomalies of non-chromosomal origin and some specific anomalies. Larger studies are needed to confirm these findings and to explore their aetiological implications.


Assuntos
Anormalidades Congênitas/epidemiologia , Estudos de Casos e Controles , Aberrações Cromossômicas/epidemiologia , Aberrações Cromossômicas/etiologia , Transtornos Cromossômicos , Anormalidades Congênitas/etiologia , Síndrome de Down/epidemiologia , Síndrome de Down/etiologia , Resíduos Perigosos/efeitos adversos , Humanos , Recém-Nascido , Idade Materna , Razão de Chances , Sistema de Registros , Fatores de Risco , Classe Social , Reino Unido/epidemiologia
16.
Semin Nucl Med ; 30(2): 133-40, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10787193

RESUMO

A marked increase in the incidence of papillary thyroid cancer in children has been documented in regions of the former Soviet Union most heavily contaminated by radioactive fallout from the Chernobyl nuclear power plant accident in April 1986. Accumulation of radioactive iodines by normal iodine trapping mechanisms resulted in significant radiation doses to the thyroid gland. Although it has long been known that thyroidal radiation resulted in nuclear and chromosomal abnormalities visible by light microscopy, modern molecular biology techniques are beginning to identify much smaller alterations in chromosomal coding sequences that are associated with malignant transformation. Although stable chromosomal abnormalities can be detected in Chernobyl-associated thyroid cancers, they are much less prevalent than in thyroid cancers developing after external beam irradiation. However, several unique chromosomal breakpoints have been described in radiation-associated thyroid cancers that are not commonly found in spontaneously occurring thyroid cancer. Furthermore, activation of specific subtypes of the ret/PTC tyrosine kinase oncogene appears to be more common in radiation-associated thyroid cancers than in spontaneous thyroid cancers. In summary, thyroid cancers developing in the aftermath of the Chernobyl accident provide a unique opportunity to search for chromosomal abnormalities that may be specific for radiation-induced thyroid cancer.


Assuntos
Neoplasias Induzidas por Radiação , Liberação Nociva de Radioativos , Neoplasias da Glândula Tireoide/etiologia , Aberrações Cromossômicas/etiologia , Transtornos Cromossômicos , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Induzidas por Radiação/diagnóstico , Neoplasias Induzidas por Radiação/epidemiologia , Neoplasias Induzidas por Radiação/genética , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/epidemiologia , Neoplasias da Glândula Tireoide/genética , Ucrânia
19.
Acta Biomed Ateneo Parmense ; 71 Suppl 1: 473-8, 2000.
Artigo em Italiano | MEDLINE | ID: mdl-11424791

RESUMO

The introduction and widespread application of Assisted Reproductive Techniques (ART) have raised major concern about the offspring 's health. The incidence of congenital and chromosomal anomalies after standard In Vitro Fertilization and Embryo Transfer seems to be similar to that expected in the general population. The prevalence of congenital malformations does not seem to be higher in children conceived by ICSI. On the other hand, it seems that there is a slight risk for transmission of chromosomal aberration of paternal origin and a certain risk of de novo sex-chromosomal and structural aberrations after ICSI. We report the results of the follow-up of 938 children conceived in our public ART by standard IVF(649) and by ICSI(289) from 21-2-1987 to 30-6-1999. The incidence of the congenital malformations results of the 1.8% (17/938); the incidence of chromosomal anomalies results 0.5% (5/938). The incidence of congenital malformations and chromosomal anomalies results 1.5% (10/649) and 0.6% (4/649), respectively, for standard IVF and 2.4% (7/289) and 0.3% (1/289) for ICSI. Our data seems to be reassuring but the incidence of chromosomal anomalies in ICSI children needs further investigation.


Assuntos
Aberrações Cromossômicas/epidemiologia , Anormalidades Congênitas/epidemiologia , Transferência Embrionária/efeitos adversos , Fertilização In Vitro/efeitos adversos , Aberrações Cromossômicas/etiologia , Transtornos Cromossômicos , Anormalidades Congênitas/etiologia , Humanos , Incidência , Recém-Nascido
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