RESUMEN
Remarkable chromosome abnormalities were observed in bone marrow cells from a woman with chronic myelocytic leukemia and atypical tuberculosis due to Mycobacterium avium-intracellulare infection. Four chromosome breaks occurred at bands 1p13, 1q32, 11p15, and 22q11. These breaks resulted in a complex Philadelphia (Ph) translocation between chromosomes #1, #11, and #22 and in an inversion of chromosome #1. Oncogenes on these chromosomes include N-ras and c-sk on chromosome #1, c-H-ras on chromosome #11, and c-sis on chromosome #22. Complex chromosome rearrangements may facilitate multiple oncogene changes, thereby permitting several steps in cancer development to occur simultaneously.
Asunto(s)
Inversión Cromosómica , Cromosomas Humanos 21-22 e Y , Leucemia Mieloide/genética , Translocación Genética , Adulto , Médula Ósea/microbiología , Médula Ósea/patología , Bandeo Cromosómico , Femenino , Humanos , Cariotipificación , Leucemia Mieloide/complicaciones , Hígado/microbiología , Hígado/patología , Ganglios Linfáticos/patología , Mycobacterium avium/aislamiento & purificación , Tuberculosis/complicacionesAsunto(s)
Plaquetas/enzimología , Carbolinas/sangre , Indoles/sangre , Metilenotetrahidrofolato Deshidrogenasa (NADP)/sangre , Oxidorreductasas/sangre , Serotonina/sangre , Animales , Encéfalo/enzimología , Carbolinas/metabolismo , Humanos , Cinética , Metilenotetrahidrofolato Deshidrogenasa (NADP)/aislamiento & purificación , Metilenotetrahidrofolato Deshidrogenasa (NADP)/metabolismo , Ratas , Serotonina/metabolismo , Tetrahidrofolatos/sangre , Tetrahidrofolatos/metabolismoRESUMEN
The function of 5'-nucleotidase in nucleoside uptake from AMP was investigated in human lymphocytes by comparing the transport in cells containing this enzyme (5'N+) with that in cells deficient in the activity (5'N-). The rate of adenosine and Pi uptake from AMP was 3.9-fold greater in the 5'N+ then in the 5'N- lymphocytes. There was no difference in transport between these cells when incubated with adenosine or Pi. These results indicate that phosphorylytic cleavage of AMP by 5'-nucleotidase is necessary for the uptake of the nucleotide and Pi moieties by the human lymphocyte.
Asunto(s)
Adenosina Monofosfato/metabolismo , Adenosina/metabolismo , Linfocitos/metabolismo , Nucleotidasas/metabolismo , Transporte Biológico Activo , Boratos/farmacología , Cianuros/farmacología , Fluoruros/farmacología , Humanos , Inosina/análogos & derivados , Inosina/farmacología , Yodoacetatos/farmacología , Cinética , Linfocitos/efectos de los fármacosRESUMEN
Contrary to previous reports, 5-methyltetrahydrofolic acid does not mediate the methylation of dopamine to epinine. Instead, this methyl donor is degraded enzymatically to formaldehyde, which condenses with dopamine to form a tetahydoisoquinoline derivative. The latter has chromotographic characteristics very similar to those of epinine, which likely accounts for the original misidentification of the product.