RESUMO
We report a 9-year-old girl who had massive bone marrow infiltration of tumor cells at the onset of alveolar rhabdomyosarcoma. She was admitted to a surgical hospital because of abdominal pain and tumor in the buttock. Computerized tomographic scans of the pelvis revealed an abnormal mass. She was referred to our department. Hematological examination showed pancytopenia. Blood chemistry revealed hypercalcemia and hyperuricemia. Bone marrow was occupied with 100% tumor cells. Chromosome analysis of tumor cells in bone marrow revealed a specific translocation, t(2;13) (q37;q14). This finding enabled the diagnosis of a disseminated alveolar rhabdomyosarcoma to be established. She was treated with vincristine, cyclophosphamide and epirubicin, achieved a complete remission, but died of relapse 3 months after diagnosis.
Assuntos
Doenças da Medula Óssea/genética , Cromossomos Humanos Par 13 , Cromossomos Humanos Par 2 , Neoplasias Pélvicas/genética , Rabdomiossarcoma/genética , Translocação Genética , Doenças da Medula Óssea/patologia , Criança , Feminino , Humanos , Invasividade Neoplásica , Metástase Neoplásica , Neoplasias Pélvicas/patologia , Rabdomiossarcoma/patologiaRESUMO
Threonine deaminase (l-threonine dehydratase EC 4.2.1.16) has been partially purified from a new extreme thermophilic bacterium, Thermus X-1, which is similar to T. aquaticus YT-1. The threonine deaminase of strain X-1 has a maximal rate of reaction at 85 to 90 C and is more thermostable than the threonine deaminase from mesophilic bacteria. The enzyme has an apparent molecular weight of 100,000 to 115,000, a K(m) for l-threonine of 14 mM, a pH optimum of 8.0, and like other threonine deaminases also catalyzes the deamination of serine. However the Thermus X-1 threonine deaminase does not show a strong feedback inhibition by isoleucine. It is suggested that the regulation of the biosynthesis of isoleucine in this extreme theromophile may resemble that reported in Rodospirillum rubrum.
