RESUMEN
We report a unique case of primary multiple liponeurocytoma. Liponeurocytoma is a rare benign tumor (Grade II) of the posterior cranial fossa with neural- or probably astrocytic-lineage cells; the tumor stroma contains mature adipocytes. This case is the thirty-eighth case of this pathology reported in the world literature and the first case of multiple form of this disease. We have provided a sufficiently thorough neuroradiological and histological picture that allows one to differentiate between a liponeurocytoma and other histological variants. Recommendations for the tactics for managing patients with this rare disease are proposed based on the analysis of treatment of this pathology reported in the world literature.
Asunto(s)
Neoplasias Cerebelosas/diagnóstico , Neoplasias del Ventrículo Cerebral/diagnóstico , Lipoma/diagnóstico , Neoplasias Primarias Múltiples/diagnóstico , Neurocitoma/diagnóstico , Neoplasias de la Médula Espinal/diagnóstico , Neoplasias Cerebelosas/radioterapia , Neoplasias Cerebelosas/cirugía , Neoplasias del Ventrículo Cerebral/radioterapia , Neoplasias del Ventrículo Cerebral/cirugía , Terapia Combinada , Humanos , Lipoma/radioterapia , Lipoma/cirugía , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Neoplasias Primarias Múltiples/radioterapia , Neoplasias Primarias Múltiples/cirugía , Neurocitoma/radioterapia , Neurocitoma/cirugía , Neoplasias de la Médula Espinal/radioterapia , Neoplasias de la Médula Espinal/cirugía , Resultado del TratamientoRESUMEN
Data on the molecular arrangement of viruslike particles (VLPs) of yeast and Drosophila retrotransposons are presented. Two methods for identifying VLPs from specific retrotransposon families have been offered. The first method is based on VLPs fractionation by electrophoresis in agarose gel under strictly controlled conditions. VLPs of the Drosophila melanogaster retrotransposon families copia and gypsy and D. virilis retrotransposon Tv1 were identified by this method. The method based on heterologous induction of retrotransposons in cells of the mutant spt3 strain of Saccharomyces cerevisiae was used to identify VLPs of yeast retrotransposon Tyl and D. melanogaster gypsy retrotransposon.
Asunto(s)
Drosophila melanogaster/genética , Drosophila/genética , Polimorfismo Genético , Retroelementos/genética , Saccharomyces cerevisiae/genética , Virión/genética , Animales , Fraccionamiento Químico , Drosophila/citología , Drosophila melanogaster/citología , Electroforesis en Gel de Agar , Microscopía Electrónica , Regiones Promotoras Genéticas , Saccharomyces cerevisiae/citología , Transformación GenéticaRESUMEN
A new method was developed to study the mechanism of initiation of the retrotransposition cycle: retrotransposons of Drosophila melanogaster, gypsy, copia, and 17.6 were expressed in yeast under the control of potent yeast promoters. Expression of retrotransposons induced formation of viruslike particles (VLPs) associated with full-length Ty1 RNA and DNA sequences. This phenomenon was termed heterologous induction. When the gene for reverse transcriptase of human immunodeficiency virus (HIV) was expressed in yeast, the same results were obtained. These data allowed us to assume the excess of active reverse transcriptase to play the central role in induction of transposition. Possible mechanisms of induction of Ty1 transposition by homologous and heterologous elements are discussed.