RESUMO
We report a case of a 25 year old man presenting with acute headache, vomiting and nuchal rigidity. Computed Tomography (CT) scan and MRI without contrast showed a right ventricular hemorrhage surrounding a mass lesion. The tumor and hematoma were completely removed by neurosurgical transcortical-transventricular approach. Anatomopathological analysis revealed a central neurocytoma. Central neurocytoma seldom present with hemorrhage. We review 16 cases of neurocytoma with hemorrhage. It is important to recognize central neurocytoma as a cause of intraventricular hemorrhage, especially in adolescents and young adults. Outcome is often favorable when the tumor is completely removed. In some patients the clinical course is more aggressive and additional treatment such as radiotherapy, radiosurgery or chemotherapy is needed.
Assuntos
Hemorragia Cerebral/etiologia , Neoplasias do Ventrículo Cerebral/complicações , Neoplasias do Ventrículo Cerebral/patologia , Neurocitoma/complicações , Neurocitoma/patologia , Adulto , Neoplasias do Ventrículo Cerebral/cirurgia , Humanos , Imageamento por Ressonância Magnética , Masculino , Neurocitoma/cirurgia , Procedimentos Neurocirúrgicos , Tomografia Computadorizada por Raios XRESUMO
As part of the European Scientists Sequencing Arabidopsis program, a contiguous region (396607 bp) located on chromosome 4 around the APETALA2 gene was sequenced. Analysis of the sequence and comparison to public databases predicts 103 genes in this area, which represents a gene density of one gene per 3.85 kb. Almost half of the genes show no significant homology to known database entries. In addition, the first 45 kb of the contig, which covers 11 genes, is similar to a region on chromosome 2, as far as coding sequences are concerned. This observation indicates that ancient duplications of large pieces of DNA have occurred in Arabidopsis.
Assuntos
Duplicação Gênica , Genes de Plantas , Proteínas de Homeodomínio/genética , Proteínas Nucleares/genética , Proteínas de Plantas/genética , Arabidopsis/genética , Proteínas de Arabidopsis , Sequência de Bases , Mapeamento Cromossômico , Mapeamento de Sequências Contíguas , DNA de Plantas , Genoma de Planta , Íntrons , Computação Matemática , Dados de Sequência Molecular , Família MultigênicaRESUMO
As a contribution to the European Scientists Sequencing Arabidopsis (BIOTECH ESSA) project, a contig of almost 40kb has been sequenced at the extreme top of chromosome 1, around the Arabidopsis thaliana gene coding for a member of the 1-aminocyclopropane-1-carboxylate synthesis gene family. The region contains, besides the ACS1 gene itself, 10 putative genes, all new for Arabidopsis. Among these are three genes encoding kinases, a late embryogenesis-abundant protein, a MADS box-containing protein, a dehydrogenase, and a Myb-related transcription factor. In addition, six cDNAs have been sequenced that correspond to this region.
Assuntos
Arabidopsis/genética , Cromossomos/genética , DNA de Plantas/genética , Proteínas Proto-Oncogênicas c-myb , Arabidopsis/química , Proteínas de Arabidopsis , Mapeamento Cromossômico , Clonagem Molecular , DNA de Plantas/química , Proteínas de Ligação a DNA/genética , Expressão Gênica/genética , Genes de Plantas/genética , Genoma de Planta , Proteínas de Domínio MADS , Dados de Sequência Molecular , Oxirredutases/genética , Fosfotransferases/genética , Proteínas de Plantas/genética , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Fatores de Transcrição/genéticaRESUMO
As part of the European Union program of European Scientist Sequencing Arabidopsis (ESSA), the DNA sequence of a 24.053-bp insert of cosmid clone CC17J13 was determined. The cosmid is located on chromosome 1 at the PFL locus (position 30 cM). Analysis of the sequence and comparison to public databases predicts seven genes in this area, thus approximately one gene every 3.3 kb. Three cDNAs corresponding to genes in this region were also sequenced. The homologies and/or possible functions of the (putative) genes are discussed. Proteins encoded by genes in this region include a polyadenylate-binding protein (PAB-3) and a GTP-binding protein (Rab7) as well as a novel protein, possibly involved in double-stranded RNA unwinding and apoptosis. Intriguingly, the gene encoding the PAB-3 protein, which is very specifically expressed, is flanked by putative matrix attachment regions.
Assuntos
Arabidopsis/genética , Mapeamento Cromossômico , Proteínas rab de Ligação ao GTP , Sequência de Bases , DNA Complementar , DNA de Plantas/química , Bases de Dados como Assunto , Europa (Continente) , Proteínas de Ligação ao GTP/genética , Genoma de Planta , Dados de Sequência Molecular , Proteínas de Ligação a Poli(A) , Proteínas de Ligação a RNA/genética , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico , proteínas de unión al GTP Rab7RESUMO
The influence of Mg2+ ions on the secondary and tertiary structure of the RNA from bacteriophage MS2 was investigated by small-angle X-ray scattering and light scattering and by sedimentation experiments. The analysis of the outer part of the X-ray scattering curve obtained at low temperature in the absence of Mg2+ yielded a cross-section radius of gyration of 0.88 nm and a mass per unit length of 1720 g mol-1 nm-1. Very similar values for these parameters, which refer to the secondary structure of the RNA molecule, were also derived from the X-ray scattering curves obtained in the presence of different amounts of Mg2+ (0.07 to 1 ions per nucleotide). On the contrary, the inner part of the X-ray scattering curves turned out to be highly dependent on the Mg2+ concentration: the cross-section radius of gyration and the mass per unit length, which were determined from the scattering curves at small angles as parameters related to the tertiary structure of the RNA, amounted to 3.11 nm and 4000 g mol-1 nm-1, respectively, in the absence of Mg2+ and increased significantly upon raising the concentration of Mg2+. The increase of these structural parameters was found to be accompanied by a decrease of the overall radius of gyration (as revealed indirectly by X-ray scattering and directly by light scattering measurements) and by an increase of the sedimentation coefficient. The results from the investigations of the RNA at low temperature clearly establish the existence of double-stranded structures down to very low Mg2+ concentrations as well as the occurrence of Mg2+ induced changes of the tertiary structure.(ABSTRACT TRUNCATED AT 250 WORDS)