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I Larripa

Publications and source records attributed to I Larripa.

At least 73 records · Page 4Linked to original sources
PubMed1975

Minute chromatin bodies in a murine in vitro cell line.

A murine anaplastic sarcoma and an in vitro cell line established from it were studied by the TG banding technique. The neoplasm originated in a BALB/c mouse inoculated with human tumor cells. Microchromatin bodies were found in 100% of the karyotypes in the original tumor and in the 120 in vitro passages. A long marker chromosome, also observed in all metaphases, was interpreted as a translocation in tandem of a No. 16 chromosome into a No. 1; this involved loss of the centromeric part of chromosome No. 1.

Animals↗
PubMedDate not supplied

Characterization of IIB-MEL-J: a new and highly heterogenous human melanoma cell line.

A highly heterogeneous cell line, IIB-MEL-J, was established from a human metastatic melanoma. This cell line contains small cells, dendritic cells, and megacells with multiple nuclei. IIB-MEL-J expresses S 100, cytokeratin intermediate filaments and the gangliosides GD2 and GD3. It requires growth factors (insulin, EGF, and transferrin) and antioxidants for optimal growth. When plated under optimal conditions, IIB-MEL-J grows with a doubling time of 70-80 hours. The cells may be fractionated by Percoll gradient centrifugation into several subpopulations (A, B, and C) with different characteristics. Subpopulation A is the slowest growing, and most of the DNA-synthesizing cells are concentrated in fractions B and C. Every subpopulation expresses S 100 and cytokeratin intermediate filaments, whereas only subpopulation B and C express GD2 and GD3. Pigmented cells are concentrated mainly in subpopulation C. Cytogenetic analysis of IIB-MEL-J revealed extensive chromosomal alterations, including a highly heterogeneous chromosome number and chromosomal rearrangements, gains, losses, isochromosomes, and double minutes. This highly heterogeneous cell line may be helpful to study cellular differentiation and interaction between different subpopulations in human melanoma.

Cell Transformation, Neoplastic↗
PubMedDate not supplied

Cytogenetic study of 50 de novo cases of ANLL from Argentina.

BACKGROUND AND METHODS: Consistent and specific chromosomal aberrations have been observed in an increasing number of neoplasias. In the present report, we describe the cytogenetic findings from 50 cases of de novo ANLL in Argentina, South America, studied at diagnosis. In addition, their relation with the FAB classification is analyzed. Children with Down's syndrome and secondary ANLL were excluded from this analysis. RESULTS AND CONCLUSIONS: Out of 50 banded cases studied, 11 (22%) had normal karyotype, while the remaining 39 (78%) presented abnormal metaphases with structural alterations in the majority of them. Chromosomes 7 and 22 were most frequently involved in numerical alterations in children, while chromosomes 6, 8, 14 and 16 were the ones most often involved in adults. Consistent chromosome rearrangements were observed and they were linked to specific cytomorphologic subsets. The translocations t(8;21) and t(15;17) were seen only in M2 and M3, respectively. The inversion of chromosome 16, inv(16), was a typical finding in M4, but was not restricted to this subtype. Translocation t(2;3) was observed in three cases, all M4, each with a variable chromosome pattern. These results are in accordance with cytogenetic findings in Western Europe and the USA.

Adolescent↗
PubMedDate not supplied

Leukemic transformation in patients with 5Q- and additional abnormalities.

BACKGROUND AND METHODS: We analyze myelodysplastic patients with the 5q- marker as sole abnormality, or with additional anomalies, and their relationship to clinical evolution. The study was performed on 12 patients (6 females and 6 males): 3 with refractory anemia (RA), 5 with RA with ring sideroblasts (RA-S), 3 RA with excess of blasts (RAEB) and 1 with RAEB in transformation (RAEB-T). The cytogenetic study was carried out on bone marrow cells at the time of diagnosis. The G- banding technique was used for chromosome identification. The follow-up was for 50 months. RESULTS AND CONCLUSIONS: Five patients (3 with RA and 2 with RA-S) showed a single 5q- marker. They had a long survival without evolution to leukemia. All cases with 5q- plus additional abnormalities: del(12p), del(7q), del(14q), i(11q) and i(17q), showed a neoplastic evolution in a short period of time. We can conclude that the presence of the 5q- marker with complex karyotypes or additional abnormalities is associated with a high risk of neoplastic evolution, indicating the prognostic value of cytogenetic study in myelodysplasia.

Aged↗