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T Lukusa

Publications and source records attributed to T Lukusa.

25 records · Page 2Linked to original sources
PubMed1991

Role of gonadal dysgenesis in gonadoblastoma induction in 46, XY individuals. The Leuven experience in 46, XY pure gonadal dysgenesis and testicular feminization syndromes.

To stress the importance of gonadal dysgenesis in the genesis of gonadoblastoma in the presence of the Y-chromosome, the authors report their experience on 7 patients with 46, XY Pure Gonadal Dysgenesis (PGD) and 14 patients with complete or incomplete forms of Testicular Feminization (TF) syndrome. The diagnostic criteria and the clinical and pathological findings are reviewed. Four patients with PGD were found to be affected by bilateral (1 patient) or unilateral (1 patient) gonadoblastomas, and by extragonadal (1 patient) or gonadal (1 patient) dysgerminoma, whereas no gonadal tumors were encountered in testes of patients with complete (CTF) or incomplete (ITF) forms of TF, underlining the pathogenic role of the gonadal dysgenesis.

Adolescent↗
PubMed1990

No significant increase in spontaneous and ethyl methane sulfonate-induced sister chromatid exchanges at the Xq27.3 fragile site.

The present study was performed to determine if the fra(X)(q27.3) site is inherently a high sister chromatid exchange (SCE) site independent of fragility. Therefore, we studied baseline and ethyl methane sulfonate (EMS)-induced SCEs in peripheral blood lymphocytes from 10 retarded fragile-X male patients and eight retarded nonfragile-X male controls. The distributions of SCE scores per chromosome within each experimental condition showed significant interindividual variability in response to EMS treatment in the fragile-X group. Each fragile-X patient was therefore compared with a matched control. No significant differences were found in the distribution of SCE scores per chromosome. In addition, at the Xq27 site, whatever the degree of expressed fragility, no significant differences between fragile-X and control groups were evident in the spontaneous or EMS-induced SCEs. The fra(X)(q27.3) site therefore is not a hot spot for spontaneous or EMS-induced SCEs. Because fluorodeoxyuridine (FUdR) treatment has been shown to induce SCE at this site, our results indicate that the Xq27.3 site must be structurally different from other nonfragile SCE sites.

Cells, Cultured↗
PubMed1988

SCE variability in lymphocytes and fibroblasts. A controlled study.

To determine whether the sister chromatid exchange (SCE) distributions obtained in lymphocytes and fibroblasts from different individuals are comparable, a controlled study was set up. Peripheral blood and skin biopsies were taken on the same day from five individuals living for years under the same environmental conditions. All samples were treated in the same fashion, and the SCEs were scored in 50 metaphases of peripheral blood lymphocytes and of skin fibroblasts in an early and in a late passage. A repeat blood sample was taken from the same five individuals 1 year later. Based on the results obtained in this first part of the study, five randomly chosen healthy blood donors were sampled at different times and studied in the same fashion. Each chromosome was identified, and the SCE scores were tabulated per chromosome over 50 metaphases. The statistical analysis consisted of fitting log linear models to these scores and examining the best fit by determining the exceedance probabilities (observed significance level). For lymphocytes, the results indicated that the SCE distributions depended only on the chromosome examined, and not on BrdU-exposure time, individuals, or time of sampling. Treatment with ethyl methane sulfonate (EMS) increased the number of SCEs proportionally on all chromosomes. Analysis of the SCE scores on lymphocytes and fibroblasts of the five individuals and on their low and high passage fibroblast cultures revealed the necessity of including higher order interactions in order to fit a suitable model to the data. Therefore comparison of the SCE scores of lymphocytes with those of fibroblasts or comparison of scores on fibroblasts from different individuals could not be done. In practice, to compare samples or individuals, it suffices to score the SCE on a limited number of chromosomes (e.G., the A group) of 50 metaphases.

Adult↗
PubMed1986

Internal male pseudohermaphroditism in a 6 week old child.

Here we describe a 6-week-old infant with internal male pseudo-hermaphroditism, detected during the repair of a left inguinoscrotal hernia. We advocate early orchidopexy during a first laparatomy and call attention to the risk of adhesions and subsequent complications if the gonads are replaced into the peritoneal cavity in advance of a precise histological and cytogenetic diagnosis.

Disorders of Sex Development↗
PubMed1986

Gonadoblastoma and Y-chromosome fluorescence.

In this report we summarize our experience in 4 patients with 45,X/46,XY, one patient with 45,X/47,XYY mosaicism, and one patient with 46,XY karyotype and ambiguous external genitalia. In the 3 patients with a fluorescent Y-chromosome, the development of one or two gonadoblastomas was found, independent of the age of the patients at the time of examination. In the 3 patients with 45,X/46,XYnf mosaicism no gonadoblastoma was detected. This finding prompted us to review the data on patients reported with 45,X/46,XYnf mosaicism. Up to now, no patient with well documented 45,X/46,XYnf mosaicism and convincing evidence of development of gonadoblastoma has been reported. These data seem to confirm that alterations of the characteristic distal fluorescence of Yq may protect the dysgenetic gonad against tumoral degeneration in patients with 45,X/46,XY mosaicism. Possible mechanisms responsible for these changes in the oncogenic potential of Yq in relation with the Y chromosome fluorescence are discussed.

Adolescent↗
PubMed1986

[Sexual ambiguity and non-fluorescent Y chromosome in 45,X/46,XY mosaicism].

The authors report 2 cases of mixed gonadal dysgenesis in a 45,X/46,XYnf mosaicism. The second case could also be considered as a true hermaphrodite at the time of examination. The discussion concerns the data (clinical, anatomical, histological and cytogenetic) which allowed for the diagnosis and treatment which relies overall on the configuration of the external genitalia.

Chromosome Banding↗