RESUMO
In the search for early biological markers to detect genetic damage, a pilot study on a hydroarsenicism-exposed group was designed. Blood and urine samples were taken from 11 individuals chronically exposed and from 13 individuals with lower exposure to the metal. Lymphocyte cultures for cytogenetic studies and HGPRT assay were done with coded peripheral blood samples, while arsenic levels and the "rec assay" in B. subtilis were determined in urine samples. The highly exposed group excreted greater amounts of As, nevertheless the rec assay showed negative results. An interesting finding is that the cell-cycle kinetics exhibited a significant difference between the groups studied, the average generation time (AGT) was longer in the highly exposed group. The percentages of chromosomal aberrations and the frequencies of sister-chromatid exchanges were similar in both populations, although complex aberrations were more frequent in the highly exposed group, which also showed a higher average variation frequency in the HGPRT assay, but the 2 latter observations were not statistically significant. The lag in lymphocyte proliferation could mean an impairment of the immune response due to arsenic exposure.
Assuntos
Arsênio/toxicidade , Ativação Linfocitária , Adulto , Arsênio/urina , Biomarcadores , Células Cultivadas , Aberrações Cromossômicas , Feminino , Humanos , Hipoxantina Fosforribosiltransferase/genética , Cinética , Masculino , México , Pessoa de Meia-Idade , Testes de Mutagenicidade , Projetos Piloto , Troca de Cromátide IrmãRESUMO
El adenocarcinoma del colon es excepcionalmente raro en los ninos. Se presentan dos casos estudiados en un periodo de dos anos en el Hospital de Pediatria del Centro Medico de Occidente del IMSS. Se analiza su presentacion clinica, manejo quirurgico y control postoperatorio. Se efectuo una revision de la literatura mundial concluyendo en la necesidad de dedicar mas tiempo al estudio de este tipo de tumores en los ninos para conocer su frecuencia real y elaborar un protocolo de manejo, pues existe un punto importante:el comportamiento biologico del adenocarcinoma colonico es muy diferente al del adult