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P Simi

Publications and source records attributed to P Simi.

31 records · Page 2Linked to original sources

The unbalanced offspring of the male carriers of the 11q;22q translocation: nondisjunction at meiosis II in a balanced spermatocyte.

Carriers of the standard translocation t(11;22) (q23.3;q11.2) produce only one type of unbalanced offspring, a tertiary trisomy resulting into the karyotype 47,XX or XY, +der(22)t(11;22)(q23.3;q11.2), usually derived from the mother. The exception is one single patient 47,XY,t(11;22)(q23.3;q11.2), +der(22)t(11;22) (q23.3;q11.2)pat. We report a second case with the same karyotype, also of paternal origin. Thus, the rare unbalanced offspring of a carrier father (only 5 cases known) may receive a supernumerary der(22), as a consequence of tertiary trisomy, but also as a consequence of nondisjunction at meiosis II of a balanced spermatocyte.

Chromosome Banding↗

Clonal chromosome changes in renal carcinoma do not correlate with clinical stages and histopathologic grades.

We analyzed the correlations between chromosome abnormalities and clinical and histopathologic characteristics in 77 cases of renal cell carcinoma (RCC). Chromosome changes such as +5,+7,+8,+10,+18,+X,+Y, and -Y have been excluded from the analysis because they also occur in nonneoplastic kidney tissue and cytogenetic analysis indicates that these anomalies are not involved in tumor progression. The most frequent specific chromosome abnormalities in this sample were 3p rearrangements, trisomy 17, and hyperdiploidy and were not related to tumor stage or grade or to development of distant metastases.

Adult↗

A deletion map of the human Yq11 region: implications for the evolution of the Y chromosome and tentative mapping of a locus involved in spermatogenesis.

A deletion map of Yq11 has been constructed by analyzing 23 individuals bearing structural abnormalities (isochromosomes, terminal deletions and X;Y, Y;X, or A;Y translocations) in the long arm of the Y chromosome. Twenty-two Yq-specific loci were detected using 14 DNA probes, ordered in 11 deletion intervals, and correlated with the cytogenetic map of the chromosome. The breakpoints of seven translocations involving Xp22 and Yq11 were mapped. The results obtained from at least five translocations suggest that these abnormal chromosomes may result from aberrant interchanges between X-Y homologous regions. The use of probes detecting Yq11 and Xp22.3 homologous sequences allowed us to compare the order of loci within these two chromosomal regions. The data suggest that at least three physically and temporary distinct rearrangements (pericentric inversion of pseudoautosomal sequences and/or X-Y transpositions and duplications) have occurred during evolution and account for the present organization of this region of the human Y chromosome. The correlation between the patient' phenotypes and the extent of their Yq11 deletions permits the tentative assignment of a locus involved in human spermatogenesis to a specific interval within Yq11.23.

Adolescent↗

Correlation between cytogenetic and histopathological findings in 65 human meningiomas.

The correlations between cytogenetic and histopathological findings were analyzed in 65 cases of human meningiomas. Clonal chromosome abnormalities were present in 28 cases (43%). The overall female/male ratio was 1.7, but it was 1.1 in the group of 28 cases with chromosomal abnormalities. Abnormalities of chromosome 22 as sole abnormality predominate in the female patients. The mean age of patients with normal karyotype was significantly lower (50.7 years) than that of patients with chromosome changes (57.3 years). The tumor origin was predominantly at the base in the patients with normal karyotype but different at the convexity, falx cerebri, and spinal cord. The five abnormal cases from the spinal cord all showed involvement of chromosome 22. The proportion of chromosome anomalies was different in the various histological types, and a significant difference was found between the meningotheliomatous (23%) and psammomatous (58%) types. The cytogenetically abnormal cases of the psammomatous type all showed involvement of chromosome 22. In three patients with multiple meningiomas, we found different karyotypes in the different tumors of the same patient, which may indicate a multifocal origin of the tumors.

Adult↗

A constitutional 5q23 deletion.

A 14 month old girl was found to have a deletion of the whole of band 5q23. By comparing 19 other cases monosomic for a part of the 5q13-q31 segment, the constitutional 5q interstitial deletions fall into two groups: adult patients with Gardner-like symptoms and mental retardation associated with deletion 5q21-q22, and patients (mostly children) with unspecific signs and symptoms and different deletions.

Chromosome Deletion↗

Chronic lymphocytic leukemia (B-cell) in the course of polycythemia vera. Description of a case with an unusual chromosomic anomaly.

The present paper describes the case of a patient who developed a B-cell chronic lymphocytic leukemia (B-CLL) 15 months after the diagnosis of polycythemia vera, which had been treated only with phlebotomies. In spite of lymphocytosis and the clinical signs and symptoms of leukemia, the patient exhibited at the same time presumptive elements of polycythemia (high LAP index levels, a high number of neutrophils). Cytogenetic investigations, carried out after the appearance of B-CLL, revealed the presence of an unusual abnormality (18 p+) both in bone marrow not stimulated by mitogens and in PWM-stimulated circulating lymphocytes. This case, which is the ninth of its kind described in the literature, offers some interesting observations about the association between myeloproliferative and lymphoproliferative syndromes.

Aged↗

Recessive cancer genes in meningiomas? An analysis of 31 cases.

Cytogenetic studies on 31 human meningiomas revealed clonal abnormalities in 14 of them. Monosomy 22 was present in three cases as the only abnormality, and in five it was associated with monosomy 18, monosomy 14, loss of X, loss of Y, and trisomy 20, respectively. We found a number of rearrangements involving chromosome #22: an i psu dic(22)(pter----q11::q11----pter) in two cases and a t(18;22)(q12;q11) in another case. Two cases showed a complex translocation involving #7 and #14: t(2;7;14)(q23;q36;q22) and t(1;7;14)(q25;q32;q22), respectively. Other clonal chromosome abnormalities were del(1p) (present in two cases); der(9)t(9;?)(q34;?); der(7)t(7;?)(q31;?); der(22)t(22;?)(q11;?); and a 9p+ chromosome. The relevance for the pathogenesis of human meningiomas of these chromosome anomalies is also discussed with reference to the previous literature. The possible involvement of recessive cancer genes present on the long arm of chromosome #22 is also discussed.

Adult↗

Central precocious puberty in 48,XXYY Klinefelter syndrome variant.

We report the first case of central precocious puberty in a patient with 48,XXYY Klinefelter syndrome variant. We also report clinical characteristics, growth pattern, endocrine data and pathological testicular findings. The patient did not receive medical care for his precocious pubertal development, because of adequate height prognosis, and reached normal height for both his target height and Klinefelter patients. Since precocious puberty seems to occur in Klinefelter syndrome and its variants, we advise karyotype analysis in boys with mental retardation, gynecomastia, small testes and precocious onset of puberty.

Abnormalities, Multiple↗

Pericentric inversion of chromosome 5: a possible threat to male fertility?

Pericentric inversion of chromosome 5 (inv(5)(p12,q13] was diagnosed in two unrelated men with normal phenotype referred for infertility. The spermatogenic damage in these patients may be explained on the basis of the X-Y bivalent behaviour in cases of some balanced structural rearrangements of the chromosomes. The Authors propose a possible negative action of inv(5) in male gamete production and suggest a larger use of the chromosome analysis in the study of male infertility.

Adult↗

Centralized cytogenetic analysis of pediatric acute leukemia: results of an Italian collaborative experience.

BACKGROUND AND OBJECTIVE: Cytogenetic analysis of acute leukemia yields important information which has been demonstrated to be correlated to patient survival. A reference laboratory was created in order to perform karyotype analysis on all cases of acute leukemia enrolled in the AIEOP (Associazione Italiana Emato-Oncologia Pediatrica) protocols. METHODS: From January 1990 to December 1995, 1115 samples of children with ALL or AML were sent in for cytogenetic analysis. The results of cell cultures were screened in the Reference Laboratory and then the fixed metaphases were sent to one of the six cytogenetic laboratories for analysis. RESULTS: The leukemic karyotypes of 556 patients were successfully analyzed. An abnormal clone was detected in 49% of cases of ALL and in 66% of AML. In ALL the most frequent abnormality was 9p rearrangement. Other recurrent abnormalities were t(9;22), t(4;11) and t(1;19). In AML t(8;21), t(15;17) and 11q23 rearrangement were the most frequent structural abnormalities. These findings are similar to the results obtained in other multicenter studies using a similar approach. INTERPRETATION AND CONCLUSIONS: Our data confirm the feasibility of performing cytogenetic analysis in a centralized laboratory on mailed samples of bone marrow and/or peripheral blood; this is very important considering that cytogenetic analysis of neoplastic tissue requires a special laboratory and expert staff.

Acute Disease↗