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1.
J Exp Med ; 169(3): 953-72, 1989 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-2494294

RESUMEN

Normal human kidney proximal tubule cells into which a ras oncogene was inserted undergo a series of transformation-related alterations that are characteristic of renal carcinomas. These include changes in morphology, growth potential, anchorage dependence, antigen expression, growth factor production, and chromosomal stability. Further, there are spontaneous progressive alterations in vitro in the karyotype and antigenic profile of the transformed cells. Cytogenetic analyses suggest that alterations of chromosome 21 may play an early and pivotal role in the development of transformed proximal tubule cells.


Asunto(s)
Transformación Celular Neoplásica , Transformación Celular Viral , Genes ras , Neoplasias Renales , Túbulos Renales Proximales , Retroviridae/genética , Antígenos de Neoplasias/análisis , Antígenos de Superficie/análisis , División Celular , Línea Celular Transformada , Cromosomas Humanos Par 21 , Gangliósidos/inmunología , Sustancias de Crecimiento/biosíntesis , Humanos , Cariotipificación , Neoplasias Renales/genética , Neoplasias Renales/inmunología , Neoplasias Renales/patología , Túbulos Renales Proximales/inmunología , Túbulos Renales Proximales/patología , Fenotipo , Células Tumorales Cultivadas
2.
Leukemia ; 4(9): 625-30, 1990 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2168505

RESUMEN

Immunohistochemical and immunophenotypic analyses were performed on 278 cases of karyotypically abnormal non-Hodgkin's lymphoma (NHL). Excluding cases of lymphoblastic lymphoma or mycosis fungoides, 20 cases showed evidence of non-B cell lineage. T cell lineage was proven by genotypic and immunophenotypic analyses in 15 of the 20 cases; five were of ambiguous lineage. All of the non-B lineage cases were of diffuse histology with a large cell component (DLCL). Twelve cases expressed the Ki-1 antigen; five of these cases also demonstrated a translocation with a break at 5q35. Patients with Ki-1 positive DLCL and t(5q35) had a younger median age compared with non-B cell DLCL without t(5q35). The Ki-1 positive patients had a higher frequency of skin involvement and lower incidence of bone marrow involvement compared with Ki-1 negative DLCL. Survival analysis was performed on 86 cases of B cell DLCL and 18 cases of non-B cell DLCL which were serially ascertained prior to receiving cytotoxic chemotherapy. Median duration of complete remission was significantly longer in the B cell compared with the non-B cell DLCL groups; there was only a trend for decreased overall survival in the non-B cell group. Among the subset of non-B cell lymphomas, overall survival of patients with Ki-1 expressing DLCL was significantly longer than those with Ki-1 negative DLCL, who had a median survival of less than a year. These results show that immunophenotypic, immunohistochemical, and cytogenetic markers can define subsets of patients with non-B cell lymphomas with differing clinical characteristics and outcome.


Asunto(s)
Antígenos CD/metabolismo , Antígenos de Diferenciación/metabolismo , Antígenos de Neoplasias/metabolismo , Linfoma no Hodgkin/inmunología , Adolescente , Adulto , Anciano , Antígenos CD/genética , Antígenos de Diferenciación/análisis , Antígenos de Diferenciación/genética , Antígenos de Neoplasias/genética , Niño , Cromosomas Humanos Par 2 , Cromosomas Humanos Par 5 , Femenino , Humanos , Inmunohistoquímica , Antígeno Ki-1 , Linfoma no Hodgkin/clasificación , Linfoma no Hodgkin/genética , Masculino , Persona de Mediana Edad , Fenotipo , Pronóstico , Linfocitos T , Translocación Genética
3.
Eur J Cancer ; 28A(4-5): 762-6, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1326305

RESUMEN

Monoclonal antibody (Mab) mediated immunotherapy of brain tumours requires the identification of tumour-restricted cell surface antigens. We have characterised four primitive neuroectodermal tumours, which included pineoblastoma, medulloblastoma and ependymoblastoma cultures, that demonstrated in vitro evidence of malignant behaviour (anchorage-independent growth and nu/nu xenograft tumour formation). The cytogenetic findings ranged from normal G-banded and Q-banded karyotypes through mixed near-diploid/hyperdiploid. These cultures resembled the cell surface immunophenotypic spectrum of malignant gliomas. They were distinguished from normal glia in vitro by the expression of restricted fetal mesenchymal, neuronal, myoblastic, melanocytic, epidermal, chondrocytic, lymphoid and epithelial antigens. Certain antigens appeared sufficiently represented among central nervous system (CNS) neoplasms to afford potential targets for Mab-mediated immunotherapy.


Asunto(s)
Neoplasias del Sistema Nervioso Central/patología , Glioma/patología , Neoplasias de Células Germinales y Embrionarias/patología , Adolescente , Anticuerpos Monoclonales , Neoplasias Encefálicas/química , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Neoplasias del Sistema Nervioso Central/química , Neoplasias del Sistema Nervioso Central/genética , Neoplasias Cerebelosas/química , Neoplasias Cerebelosas/genética , Neoplasias Cerebelosas/patología , Ependimoma/química , Ependimoma/genética , Ependimoma/patología , Femenino , Glioma/química , Glioma/genética , Humanos , Inmunohistoquímica , Inmunofenotipificación , Lactante , Cariotipificación , Masculino , Meduloblastoma/química , Meduloblastoma/genética , Meduloblastoma/patología , Neoplasias de Células Germinales y Embrionarias/química , Neoplasias de Células Germinales y Embrionarias/genética , Pinealoma/química , Pinealoma/genética , Pinealoma/patología , Células Tumorales Cultivadas
4.
J Neuroimmunol ; 25(1): 7-28, 1989 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2685039

RESUMEN

The karyotypic and antigenic phenotypes of early passage normal and malignant glial cultures were correlated in vitro. Astrocytomas (4) were distinguished from the normal glia (8) by a mixed near-diploid karyotype and anchorage-independent growth. Malignant gliomas (41) demonstrated cytogenetic abnormalities ranging from mixed normal G- and Q-banded and near-diploid cultures, through mixed near-diploid/hyperdiploid to predominantly hyperdiploid stem-lines. This correlated with the differential expression of certain antigens and established qualitative antigenic differences from normal glia. Associations were found between histopathologic grade of glial neoplasm and the expression of antigens 5.1H11 (p = 0.0002), CNT/11 (p = 0.001), CNT/10 (p = 0.004), CAT301 (p = 0.014), M111 (p = 0.024), and L101 (p = 0.044). An ominous association was demonstrated between the duration of clinical survival and the expression of antigens 5.1H11 (p = 0.0007), CNT/10 (p = 0.027) and B2.6 (p = 0.038). Correcting for diagnosis and age, multivariate analysis demonstrated that HLA-DR (p = 0.050) and 5.1H11 (p = 0.069) were unfavorably correlated with patient survival. This suggests the application of the in vitro immunophenotype for its predictive utility, as well as a novel method of selection of tumor-associated antigens for monoclonal antibody-mediated immunotherapy.


Asunto(s)
Astrocitoma/inmunología , Glioma/inmunología , Neuroglía/inmunología , Adolescente , Adulto , Astrocitoma/genética , Astrocitoma/fisiopatología , Niño , Glioma/genética , Glioma/fisiopatología , Humanos , Técnicas Inmunológicas , Cariotipificación , Neuroglía/fisiología , Fenotipo , Estadística como Asunto , Análisis de Supervivencia , Células Tumorales Cultivadas
5.
Am J Med Genet ; 102(4): 368-71, 2001 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-11503165

RESUMEN

Ring chromosomes are uncommon findings in prenatal diagnosis. Growth retardation is the most significant manifestation, in particular among patients with rings of larger chromosomes. A 30-year-old gravida 1, para 0 white woman was referred for genetic counseling because of maternal anxiety. Cytogenetic analysis of amniotic fluid cells at 16 weeks gestation revealed an abnormal mosaic female chromosome complement; 46,XX,r(11)(p15q25)[14]/45,XX,-11[7]. The ring 11 showed no detectable loss of chromosomal material at 450 band level. Both parents had a normal karyotype. Fluorescence in situ hybridization demonstrated intact subtelomeric regions in the ring chromosome. A targeted ultrasound evaluation at the time of consultation suggested no significant abnormalities. The parents were counseled and subsequently decided to terminate the pregnancy. The autopsy revealed an immature female fetus with abnormal craniofacial features including brachycephaly, low-set ears and hypertelorism, bicornuate uterus, and calcifications in the renal tubules. The abnormal phenotypes could be a consequence of the ring instability, submicroscopic deletion, and/or alteration of genetic material at the site of fusion.


Asunto(s)
Cromosomas Humanos Par 11/genética , Diagnóstico Prenatal , Cromosomas en Anillo , Adulto , Femenino , Retardo del Crecimiento Fetal/diagnóstico , Retardo del Crecimiento Fetal/genética , Edad Gestacional , Humanos , Embarazo , Diagnóstico Prenatal/métodos
6.
Am J Med Genet ; 85(5): 476-8, 1999 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-10405445

RESUMEN

A case of X-autosome translocation was diagnosed prenatally [46,X, t(X;9)(p21.3 approximately 22.1;q22]. We describe the use of fluorescence in situ hybridization (FISH) to estimate the integrity of the Duchenne muscular dystrophy (DMD) gene. X-inactivation studies were used as well to assess the probability of phenotypic abnormalities associated with functional partial disomy X and monosomy 9.


Asunto(s)
Cromosomas Humanos Par 9 , Distrofias Musculares/genética , Proteínas de Unión al ARN , Translocación Genética , Cromosoma X , Adulto , Mapeo Cromosómico , Femenino , Muerte Fetal , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil , Humanos , Hibridación Fluorescente in Situ , Cariotipificación , Masculino , Proteínas del Tejido Nervioso/genética , Embarazo , Diagnóstico Prenatal
7.
Am J Med Genet ; 90(3): 233-8, 2000 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-10678661

RESUMEN

This study is a prospective clinical trial with fluorescent in situ hybridization (FISH) as a "routine" test for prenatal detection of the most common aneuploidies in high-risk pregnancies. Since April 1996, FISH studies with multicolor, commercially available, specific probes for chromosomes 13, 18, 21, X, and Y have been routinely performed in our cytogenetic laboratory on uncultured chorionic villous samplings (CVS), amniotic fluid samples, or fetal blood obtained by cordocentesis from patients with major or minor fetal anomalies detected by ultrasonography. Among the 4,193 prenatal samples analyzed between April 1996 and June 1998, routine FISH studies were ordered by the referring physicians on 301 (7.2%) cases. Aneuploidies were detected in 32 (10.6%) samples. Fourteen trisomy-21, 10 trisomy-18, 3 trisomy-13, 4 monosomies of X, and 1 case of triploidy were diagnosed by FISH. All 1,505 hybridizations were informative, and all 301 results were available and reported to the referring physicians in 24-48 hr. All relevant FISH results were confirmed by subsequent cytogenetic analysis. In 10 (3.8%) cases with normal FISH results, the final cytogenetic analysis revealed abnormal chromosomal rearrangements that could not be detected by the routine FISH studies. We conclude that rapid FISH analysis of interphase, uncultured fetal cells is an accurate and very sensitive method for routine prenatal diagnosis of the most common aneuploidies in high-risk pregnancies.


Asunto(s)
Aneuploidia , Embarazo de Alto Riesgo , Diagnóstico Prenatal , Femenino , Humanos , Hibridación Fluorescente in Situ , Embarazo
8.
Am J Med Genet ; 84(1): 12-4, 1999 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-10213039

RESUMEN

We report on the prenatal diagnosis of a fetus with 46,XY and 46,XX cell lines with a normal male phenotype. Cytogenetic and molecular studies ruled out the possibility of maternal cell contamination and showed that all the X chromosomes present in both fetal cell lines were derived from a single maternal X chromosome. This suggests 46,XY/46,XX mosaicism.


Asunto(s)
Mosaicismo/genética , Diagnóstico Prenatal , Cromosomas Sexuales/genética , Alelos , Apolipoproteínas B/genética , Quimera/genética , Feto/metabolismo , Humanos , Masculino , Meiosis/genética , Repeticiones de Minisatélite/genética , Mitosis/genética , Fenotipo , Reacción en Cadena de la Polimerasa , Caracteres Sexuales
9.
Am J Med Genet ; 82(2): 143-5, 1999 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-9934978

RESUMEN

Interstitial deletions are relatively rare chromosomal anomalies that usually arise de novo. The data describing the phenotype associated with interstitial deletions of 5q are very limited. We describe the first case of multiple fetal anomalies, diagnosed on prenatal sonographic examination, associated with a deletion at 5q31q33. Sonographic examination at 23 weeks' gestation demonstrated growth parameters consistent with 20 weeks' gestation; a 7-mm nuchal fold; a dilated loop of bowel adjacent to the stomach suggestive of duodenal atresia; clubbing of the left foot; a narrow aorta; suspected ventricular septal defect; and placental thickening. The patient delivered a severely growth-restricted fetus and enlarged placenta at 30 weeks' gestation. The infant died neonatally.


Asunto(s)
Deleción Cromosómica , Cromosomas Humanos Par 5 , Anomalías Congénitas/genética , Adulto , Anomalías Congénitas/diagnóstico por imagen , Femenino , Humanos , Cariotipificación , Embarazo , Ultrasonografía Prenatal
10.
Cancer Genet Cytogenet ; 80(1): 60-2, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7697634

RESUMEN

A balanced reciprocal translocation, t(6;9)(p21;q34), was identified in a female patient diagnosed with chronic myeloid leukemia (CML). Both homologs of chromosome 22 were of normal length and morphology. Southern blotting revealed a bcr rearrangement with BglII and HindIII. Two signals for the abl probe were demonstrated by fluorescence in situ hybridization (FISH), one on the normal chromosome 9 and the second on a chromosome 22. Thus, molecular rearrangement of bcr resulted from insertion of an abl gene within the bcr region despite absence of a Ph chromosome.


Asunto(s)
Cromosomas Humanos Par 6 , Cromosomas Humanos Par 9 , Proteínas de Fusión bcr-abl/genética , Leucemia Mieloide Crónica Atípica BCR-ABL Negativa/genética , Translocación Genética , Femenino , Humanos , Hibridación Fluorescente in Situ , Cariotipificación , Persona de Mediana Edad
11.
J Neurol Sci ; 89(1): 79-92, 1989 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2926444

RESUMEN

The treatment of CNS neoplasms with monoclonal antibody-mediated immunotherapy optimally requires the identification of tumor restricted cell surface antigens. However, little is known regarding the antigenic phenotype(s) of malignant astrocytomas. The interrelated expression of four neuroectodermal tumor antigens, CNT/11, AJ8, A010 and CNT/2, has been studied in cultured malignant gliomas and correlated with anchorage independent growth, morphology, glial fibrillary acidic protein, and the surface expression of other antigens. Many of these latter antigens have been reported to be expressed by specific fetal and differentiated adult cell lineages or tissues, as well as certain classes of malignant tumors. The tumor-associated expression of these antigens may be broadly classified as lineage-consistent, lineage-independent or putatively tumor-restricted. Malignant glioma tumor antigenic heterogeneity represents the expression of neuroectodermal and non-neuroectodermal cell surface markers. The importance of this observation is 2-fold. Lineage-independent antigen expression may be an indication of altered genome regulatory processes within tumor cells, and thus reflect the degree of anaplasia. The identification of lineage-consistent and lineage-independent tumor associated antigens may contribute to the selection of "target" antigens and the prediction of toxicity for monoclonal antibody mediated immunotherapy.


Asunto(s)
Antígenos de Neoplasias/metabolismo , Regulación de la Expresión Génica , Glioma/metabolismo , Células Tumorales Cultivadas/metabolismo , Línea Celular , Proteína Ácida Fibrilar de la Glía/metabolismo , Humanos , Fenotipo
12.
Genet Test ; 4(1): 61-3, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10794363

RESUMEN

Fluorescence in situ hybridization (FISH) of chromosome-specific probes to interphase uncultured amniocytes was performed in cases in which follow-up amniocenteses were done for confirmation of previously detected mosaicism. FISH results were informative in all seven cases included in the study, and confirmed by subsequent cytogenetic analysis. FISH analysis provides rapid results for referral physicians and in most cases reassurance for patients within 24 hours of the follow-up aminocentesis. Although FISH studies are not considered accurate in determining a primary diagnosis of mosaicism in uncultured cells, the analysis is accurate and clinically useful when the diagnosis is known and mosaicism involving a specific chromosome needs to be confirmed in follow-up testing.


Asunto(s)
Aneuploidia , Hibridación Fluorescente in Situ , Mosaicismo/genética , Diagnóstico Prenatal/métodos , Trisomía/diagnóstico , Amniocentesis , Amnios/citología , Cromosomas Humanos Par 12/genética , Cromosomas Humanos Par 13/genética , Cromosomas Humanos Par 7/genética , Cromosomas Humanos Par 9/genética , Femenino , Estudios de Seguimiento , Humanos , Cariotipificación/métodos , Valor Predictivo de las Pruebas , Embarazo , Factores de Tiempo , Trisomía/genética , Cromosoma X/genética , Cromosoma Y/genética
13.
Waste Manag ; 29(8): 2404-9, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19380221

RESUMEN

Hazardous healthcare waste has become an environmental concern for many developing countries including the Kingdom of Bahrain. There have been several significant obstacles facing the Kingdom in dealing with this issue including; limited documentation regarding generation, handling, management, and disposal of waste. This in turn hinders efforts to plan better healthcare waste management. In this paper, hazardous waste management status in the Kingdom has been investigated through an extensive survey carried out on selected public and private healthcare premises. Hazardous waste management practices including: waste generation, segregation, storage, collection, transportation, treatment, and disposal were determined. The results of this study along with key findings are discussed and summarized. In addition; several effective recommendations and improvements of hazardous waste management are suggested.


Asunto(s)
Residuos Peligrosos/estadística & datos numéricos , Eliminación de Residuos Sanitarios/métodos , Residuos Sanitarios/estadística & datos numéricos , Bahrein , Instituciones de Salud/clasificación , Instituciones de Salud/estadística & datos numéricos , Eliminación de Residuos Sanitarios/estadística & datos numéricos , Encuestas y Cuestionarios , Transportes
14.
Blood ; 74(6): 1876-9, 1989 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-2804338

RESUMEN

Of 187 specimens of non-Hodgkin's lymphoma and four hyperplastic lymphoid proliferations with clonal chromosome abnormalities ascertained serially over a 4 1/2-year period, nine cases with t(3;22)(q27;q11) were identified. Seven of the lymphomas were diffuse tumors, predominantly large cell type. The eighth tumor, a follicular small cleaved cell lymphoma, exhibited a t(3;22) and a t(14;18)(q32;q21). The ninth case was a lymph node from a human immunodeficiency virus-positive patient which showed atypical hyperplasia. Overall survival of t(3;22) diffuse lymphoma patients was not different from that of patients with abnormal karyotypes without t(3;22). The t(3;22) diffuse tumors studied showed a disproportionate frequency of lambda light chain on their cell surfaces, a finding similar to that observed in t(8;22)(q24;q11) Burkitt's lymphomas. Our results indicate that the t(3;22)(q27;q11) is the third most common recurring translocation in diffuse non-Hodgkin's lymphoma.


Asunto(s)
Cromosomas Humanos Par 22 , Cromosomas Humanos Par 3 , Linfoma no Hodgkin/genética , Translocación Genética , Adulto , Anciano , Femenino , Humanos , Cariotipificación , Masculino , Persona de Mediana Edad
15.
J Neurooncol ; 15(3): 209-27, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8395568

RESUMEN

We compared the BCNU sensitivity of 4 freshly resected tumors (astrocytoma WM, and malignant gliomas MK, MB, and AM) and their clones to their karyology. The majority of primary cells in all 4 tumors had near-diploid chromosome numbers (2n +/-) and all were resistant to concentrations of BCNU exceeding 10 micrograms/ml. Following in vitro cultivation, the cells from tumors WM and MB retained their 2n +/- modal chromosome number with little change in the complexity of the karyotype. In contrast, tumors MK and AM demonstrated a more unstable genome. The modal chromosome number of MK shifted from 45 to 86 and that of tumor AM from 45 to 90. Karyotyping demonstrated additional ploidy changes and new marker chromosomes in both tumors. The colony forming assay (CFA) performed on the in vitro cultivated cells demonstrated little change in the sensitivity to BCNU in tumors WM and MB, while tumors MK and AM exhibited greater than a one log cell kill at 10.0 micrograms/ml and 15.0 micrograms/ml BCNU, respectively. The modal chromosome number and BCNU sensitivity followed a similar pattern in the 30 clones that were isolated; 21 clones with near-diploid and pseudodiploid chromosome numbers were all resistant to BCNU doses at or greater than 10 micrograms/ml. In contrast, 9 clones isolated from the 3 malignant gliomas with 3n +/- and 4n +/- modal chromosome numbers were sensitive to this concentration of BCNU. The karyotypes of the hyperdiploid clones were more complex; they contained 5 or more ploidy changes and/or had marker chromosomes. These studies confirm the association of diploidy and BCNU-resistance in freshly resected malignant gliomas.


Asunto(s)
Astrocitoma/genética , Neoplasias Encefálicas/genética , Carmustina/farmacología , Diploidia , Glioblastoma/genética , Células Clonales/efectos de los fármacos , Resistencia a Medicamentos/genética , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Cariotipificación , Persona de Mediana Edad , Células Tumorales Cultivadas
16.
Cancer ; 71(12): 4007-21, 1993 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-8389658

RESUMEN

BACKGROUND: Although some patients with malignant gliomas respond to treatment with chemotherapeutic agents like BCNU, tumor recurrence inevitably occurs, heralding the development of chemoresistance. Treating and/or preventing chemoresistance requires distinguishing newly developed resistance from the presence of intrinsically resistant cells in the primary tumor population. This study relates the chromosomal complements of freshly resected astrocytomas to the cells' chemosensitivity and ultimately to the patients' response to treatment. METHODS: The authors dissociated 31 freshly resected human gliomas (5 astrocytomas, 10 anaplastic astrocytomas, 16 glioblastomas multiforme) into single cells, and performed cytogenetic analysis and BCNU sensitivity testing using the colony-forming assay (CFA) on first division cells from these tumors. RESULTS: The major cytogenetic abnormalities involved the loss of a sex chromosome in all three classes of gliomas and the gain of chromosome 7 in anaplastic astrocytoma and glioblastoma multiforme; clonal marker chromosomes were observed in only anaplastic astrocytoma and glioblastoma multiforme with no common rearrangement observed among the tumors. The five astrocytomas were near-diploid (2n+/-, 35-57 chromosomes/cell), and all were resistant to BCNU. Seven of ten anaplastic astrocytomas were composed primarily of 2n+/- cells and were BCNU resistant. Three other anaplastic astrocytomas had a 39% or greater representation of 4n+/- cells (88-101 chromosomes/cell), and these tumors were sensitive to BCNU. Ten of 16 glioblastomas multiforme were composed predominantly of 2n+/- cells and were resistant to carmustine. Six other glioblastomas multiforme had at least 41% 3n+/- (58-87 chromosomes/metaphase) and 4n+/- cell populations and were sensitive to carmustine. Thus, gliomas demonstrating BCNU sensitivity were more than 60% hyperdiploid (60 or more chromosomes/metaphase) with 1 to 8 clonal marker chromosomes and multiple clonal populations involving complex karyotypic deviations. In contrast, all 22 resistant tumors were composed primarily of near-diploid cells. Only 4 of 22 tumors had a clonal marker, and the chromosome ploidy changes were less extensive. CONCLUSIONS: In freshly resected untreated human gliomas, BCNU is most effective against hyperdiploid cells that have extensive ploidy changes and chromosome rearrangement, whereas resistance to carmustine is characteristic of near-diploid populations with few ploidy changes and rearranged chromosomes. This observation was consistent for all three classes of gliomas.


Asunto(s)
Astrocitoma/genética , Neoplasias Encefálicas/genética , Carmustina/uso terapéutico , Aberraciones Cromosómicas/genética , Glioblastoma/genética , Adolescente , Adulto , Anciano , Aneuploidia , Astrocitoma/tratamiento farmacológico , Neoplasias Encefálicas/tratamiento farmacológico , Carmustina/farmacología , Niño , Trastornos de los Cromosomas , Citogenética , Diploidia , Resistencia a Medicamentos/genética , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Glioblastoma/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana Edad , Tasa de Supervivencia , Células Tumorales Cultivadas , Ensayo de Tumor de Célula Madre
17.
Fetal Diagn Ther ; 12(5): 301-3, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9430214

RESUMEN

OBJECTIVE: To evaluate the effect of fetal sex on the concentration of amniotic fluid alpha-fetoprotein (AF-AFP) in singletons and twins. MATERIAL AND METHODS: Amniocentesis was performed for advanced maternal age between 15 and 20 weeks of gestation. Only patients with normal karyotypes, uncomplicated gestations and normal ultrasound examination were included. AFP was measured in amniotic fluid by RIA and results, expressed as multiples of the median (MoM), were grouped according to fetal sex and were compared by t test. RESULTS: A total of 603 singleton pregnancies (294 females and 309 males) and 45 twin pregnancies discordant for sex met the inclusion criteria. The mean AF-AFP in singleton males was 1.06 vs. 1.04 MoM in singleton females. In twins, the mean AF-AFP was, respectively, 1.05 and 1.07 MoM (p > 0.05). CONCLUSION: Gender had no impact on AF-AFP in singleton or twin pregnancies, suggesting that the differential influence of sex hormones on the activity of the AFP gene is negligible.


Asunto(s)
Líquido Amniótico/química , Embarazo Múltiple/fisiología , Embarazo/fisiología , Caracteres Sexuales , alfa-Fetoproteínas/análisis , Adulto , Amniocentesis , Estudios de Cohortes , Femenino , Humanos , Masculino , Edad Materna , Embarazo de Alto Riesgo , Gemelos
18.
Fetal Diagn Ther ; 14(3): 181-4, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10364671

RESUMEN

Nondisjunction associated with advanced maternal age, a well-established factor in the etiology of autosomal trisomy, should equally affect all chromosomes. In this study we evaluate the association of advanced maternal age with the occurrence of potentially viable autosomal trisomies (13, 18 and 21). 275 aneuploid pregnancies were ascertained prenatally and were grouped according to chromosome anomaly diagnosed. Mean maternal age was significantly younger (p = 0.009) in pregnancies affected by trisomy 13 than in pregnancies with trisomy 21. An intermediate mean maternal age was observed in pregnancies affected by trisomy 18. Our study shows a trend of the more severe, but potentially viable, autosomal trisomies to be diagnosed at younger maternal age. This may substantiate the 'relaxed selection hypothesis' proposed to explain the association of aneuploid conceptions with advanced maternal age.


Asunto(s)
Cromosomas Humanos 13-15 , Cromosomas Humanos 16-18 , Síndrome de Down/diagnóstico , Diagnóstico Prenatal , Trisomía/diagnóstico , Adulto , Femenino , Humanos , Edad Materna , Embarazo , Embarazo de Alto Riesgo , Estudios Retrospectivos
19.
Am J Obstet Gynecol ; 171(4): 1055-7, 1994 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7943069

RESUMEN

OBJECTIVE: The development of fluorescent in situ hybridization chromosome-specific probes has allowed the use of new fetal tissue collection techniques, such as fetal cells in maternal blood and coelocentesis--both of which, with current techniques, cannot generate complete karyotypes. We evaluated chromosome-specific probes for additional potential limitations in the setting of a high-risk prenatal diagnosis center. STUDY DESIGN: The last 24 months of fetal karyotypes from our prenatal cytogenetics laboratory were analyzed for those abnormalities that should be detectable by chromosome-specific probes and those that would likely be missed. RESULTS: In 6006 karyotypes 207 (3.4%) abnormalities were found, of which 104 were common trisomies, 12 triploidies, and 19 monosomies that would have been detected with current probe combinations (13, 18, 21, X, and Y) (135/207, 65.2%). Seventy-two abnormalities (35%) represented other trisomies (16/207, 7.7% for 9, 12, 15, 16) and rearrangements (inversions, translocation markers were 56/207, 27.1%), which would have been missed. CONCLUSIONS: Use of current fluorescent in situ hybridization chromosome-specific probes protocols would have detected only 65% of chromosome abnormalities in our high-risk population. Incomplete ascertainment must be weighed against the cost and speed of fluorescent in situ hybridization chromosome-specific probes when comparing it with traditional karyotyping. Although this new technique may prove useful in low-risk screening programs (fetal cells in maternal blood), its current use in high-risk populations should be questioned until its sensitivity is expanded to identify more subtle and less common chromosomal abnormalities.


Asunto(s)
Aberraciones Cromosómicas/diagnóstico , Enfermedades Fetales/diagnóstico , Hibridación Fluorescente in Situ , Embarazo de Alto Riesgo , Diagnóstico Prenatal , Trastornos de los Cromosomas , Costos y Análisis de Costo , Sondas de ADN , Femenino , Humanos , Hibridación Fluorescente in Situ/economía , Cariotipificación , Embarazo , Diagnóstico Prenatal/economía , Sensibilidad y Especificidad
20.
Genes Chromosomes Cancer ; 2(1): 27-35, 1990 May.
Artículo en Inglés | MEDLINE | ID: mdl-2177640

RESUMEN

Although several independent series of non-Hodgkin's lymphomas (NHLs) have been subjected to cytogenetic studies or analyses of lineages by assaying for clonal immunophenotypes and clonal rearrangements affecting immunoglobulin (IG) and T-cell receptor (TCR) genes, no published reports exist of series of non-B-cell NHLs on which cytogenetic, immunohistochemical, and IG and TCR gene rearrangement studies have been undertaken together. Among 343 NHLs ascertained prospectively between January 1984 and December 1988 at the Memorial Sloan-Kettering Cancer Center, 278 cases with clonal chromosome abnormalities were identified. Of the latter, 20 were non-B-cell NHLs, which in turn comprised 15 peripheral T-cell lymphomas (PTCLs) and 5 lymphomas of uncertain lineage (LULs). The LULs either were biogenotypic, had discordant immunophenotype and immunogenotype, or showed no evidence of B-cell, T-cell, or histiocytic derivation. Of the 15 PTCLs, eight expressed the Ki-1 antigen and four of these had translocations involving the band 5q35 [t(5q35)]. Of the five LULs, four expressed the Ki-1 antigen and one of these had a translocation involving band 5q35. Previous studies have associated t(5q35) with Ki-1 positive NHLs characterized histologically by a pleomorphic diffuse large cell morphology. In our series of 12 Ki-positive non-B-cell NHLs, five (42%) had a 5q35 translocation. They were histologically indistinguishable from the subset without the translocation. The frequent lineage uncertainty exhibited by Ki-1 positive NHLs of similar histology and cytogenetic abnormalities suggests their derivation from an early uncommitted lymphoid cells.


Asunto(s)
Linfoma no Hodgkin/química , Linfoma de Células T/química , Antígenos de Diferenciación/análisis , Antígenos de Diferenciación/genética , Antígenos de Neoplasias/análisis , Antígenos de Neoplasias/genética , Biomarcadores de Tumor/análisis , Cromosomas Humanos Par 5/ultraestructura , Células Clonales/química , Células Clonales/ultraestructura , Reordenamiento Génico , Reordenamiento Génico de la Cadena beta de los Receptores de Antígenos de los Linfocitos T , Reordenamiento Génico de la Cadena gamma de los Receptores de Antígenos de los Linfocitos T , Genes de Inmunoglobulinas , Humanos , Cadenas Pesadas de Inmunoglobulina/genética , Inmunofenotipificación , Antígeno Ki-1 , Linfoma no Hodgkin/clasificación , Linfoma no Hodgkin/genética , Linfoma no Hodgkin/inmunología , Linfoma de Células T/genética , Linfoma de Células T/inmunología , Translocación Genética
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