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Biomedical subjects

M Cerda-Nicolas

Publications and source records attributed to M Cerda-Nicolas.

6 recordsLinked to original sources

Complex rearrangement of chromosomes 6 and 11 as the sole anomaly in atypical teratoid/rhabdoid tumors of the central nervous system.

Atypical teratoid/rhabdoid tumor of the central nervous system is a rare childhood tumor with a distinct histologic appearance and an aggressive clinical course. Few tumors have been analyzed cytogenetically. The only consistent chromosomal abnormality identified in some of these tumors has been monosomy or deletions of chromosome 22; in others, a normal chromosome 22 was present. The authors report an atypical teratoid/rhabdoid neoplasm of the central nervous system with a novel complex rearrangement affecting chromosomes 6 and 11 as the sole anomaly. The involvement of region 11p15 could be important in the pathogenesis of this entity.

Central Nervous System Neoplasms↗

Gliofibromas (including malignant forms), and gliosarcomas: a comparative study and review of the literature.

The presence of connective tissue elements in gliomas necessitates in every case a thorough analysis of the character and derivation of such elements to allow the formulation of an appropriate diagnosis. Four cases are presented in this paper. In cases 1 and 2 (anaplastic astrocytomas in two children, 9 and 4 years old, respectively) all the neoplastic elements were astrocytes and their ability to produce or indirectly promote the production of reticulin and collagen fibers accounted for the presence of such elements in close association with the tumor cells. The term "gliofibroma" has been coined for such tumors, but "desmoplastic astrocytoma", (low grade or anaplastic) or in highly malignant cases "desmoplastic glioblastoma", as the case may be, also seem to be appropriate terms for such neoplasms. In contrast, cases 3 and 4 represented composite tumors in adults (66 and 58 years old, respectively) and the neoplasms of these patients consisted of glioblastoma and sarcoma, the latter component demonstrably being of vascular origin. This is the type of tumor usually referred to as gliosarcoma or "Feigin tumor". Although some apparent similarities between the two groups may exist at times, the histogenesis of the latter group's sarcomatous or sarcoma-like portions is different from that of the first group and, therefore, warrants separate diagnostic terms and placement in brain tumor classification.

Aged↗

Sequential morphological and functional changes in kaolin-induced hydrocephalus.

An experimental model of kaolin-induced hydrocephalus in the dog was studied in order to evaluate the progress of ventricular dilatation and the communications between the ventricular system and the subarachnoid space. Skull and spine radiological studies were obtained after metrizamide intraventricular injection, and the baseline ventricular pressure and cerebral pulse pressure amplitude were measured in anesthetized animals. Intracranial compliance and resistance to drainage of cerebrospinal fluid were calculated by means of bolus injection test. Light and scanning electron microscope studies were done at different developmental stages of hydrocephalus. With these experimental parameters, two successive phases were seen: an initial acute hypertensive hydrocephalus (H1) with high resistance, low compliance, severe ependymal damage, and subependymal edema; and a late chronic normotensive hydrocephalus (H2) with little resistance increase, normal compliance, epithelial regeneration, and subependymal gliosis. Both the H1 and H2 stages showed an increase in the cerebral pulse pressure amplitude.

Animals↗

Presence of ganglion cells in Wilm's tumours: a review of the possible neuroepithelial origin of nephroblastoma.

Twenty-seven cases of Wilms' tumour were reviewed in order to confirm the presence of nervous tissue which could imply a 'neuroepithelial' origin for these neoplasms. For this purpose a double-silver impregnation technique was used. Groups of ganglion cells with neurofibrils and non-myelinated axon-like processes appeared associated with a fine neurofibrillar network with neuromuscular junctions. Nervous tissue in nephroblastoma is mature and should not be confused with primary ganglioneuroblastoma of the kidney in which neuroblasts in rosette-like groupings are very numerous. A case report of such a lesion is discussed for purposes of comparison.

Axons↗

Association of chromosome 7, chromosome 10 and EGFR gene amplification in glioblastoma multiforme.

Glioblastoma multiforme (GBM) is characterized by intratumoral heterogeneity in both histomorphological and genetic changes, displaying a wide variety of numerical chromosome aberrations, the most common of which are trisomy 7 and monosomy 10. The amplification of the epidermal growth factor receptor (EGFR) gene is the most frequently reported genetic abnormality. The associations between these parameters and their implication in the tumoral progression are poorly understood. We performed simultaneous fluorescence in situ hybridization (FISH) with centromeric DNA probes for chromosomes 7 and 10 in smear preparations, and EGFR gene amplification by PCR from 25 cases of GBM. Trisomy/ polysomy for chromosome 7 was present in 76% of cases and monosomy 10 in 68%. Both alterations were associated in 56% of cases. The EGFR gene was amplified in 52% of tumors; in 44% associated with trisomy/ polysomy 7, and in 36% with monosomy 10. The three parameters were associated together in 28% of cases. Kaplan-Meier survival rate analysis demonstrated lower survival rates in patients with monosomy 10, trisomy 7, and monosomy associated with trisomy 7. The other combinations were not different in frequency in relation to survival. In the present study, trisomy/polysomy 7 and monosomy 10 have been found to be frequently associated. The combination of both anomalies is probably important in the tumorigenesis of glioblastoma. Moreover, this association is apparently independent of EGFR gene amplification, which could be a later event in this process.

Adult↗

Meningiomas: karyotypes and histological patterns.

The cytogenetic findings, based on G-banding, in six meningiomas are reported. Normal karyotypes were found in three cases and monosomy of chromosome 22 in the remaining three. In one of these three cases, a malignant meningioma, several chromosomes were lost, gonosome Y included. The possible significance of the association of chromosome alterations in meningiomas with the histology of the tumor and its biological aggressivity is discussed.

Adult↗