RESUMEN
OBJECTIVES: To examine the association between methylenetetrahydrofolate reductase (MTHFR) (C677T and A1298C), methionine synthase (MTR) A2756G and methionine synthase reductase (MTRR) A66G gene polymorphisms and total homocysteine (tHcy), methylmalonic acid (MMA) and S-adenosylmethionine/S-adenosylhomocysteine (SAM/SAH) levels; and to evaluate the potential interactions with folate or cobalamin (Cbl) status. SUBJECTS/METHODS: Two hundred seventy-five healthy women at labor who delivered full-term normal babies. Cbl, folate, tHcy, MMA, SAM and SAH were measured in serum specimens. The genotypes for polymorphisms were determined by PCR-restriction fragment length polymorphism (RFLP). RESULTS: Serum folate, MTHFR 677T allele and MTR 2756AA genotypes were the predictors of tHcy levels in pregnant women. Serum Cbl and creatinine were the predictors of SAM/SAH ratio and MMA levels, respectively. The gene polymorphisms were not determinants for MMA levels and SAM/SAH ratios. Low levels of serum folate were associated with elevated tHcy in pregnant women, independently of the gene polymorphisms. In pregnant women carrying MTHFR 677T allele, or MTHFR 1298AA or MTRR 66AA genotypes, lower Cbl levels were associated with higher levels of tHcy. Lower SAM/SAH ratio was found in MTHFR 677CC or MTRR A2756AA genotypes carriers when Cbl levels were lower than 142 pmol/l. CONCLUSIONS: Serum folate and MTHFR C677T and MTR A2576G gene polymorphisms were the determinants for tHcy levels. The interaction between low levels of serum Cbl and MTHFR (C677T or A1298C) or MTRR A66G gene polymorphisms was associated with increased tHcy.
Asunto(s)
5-Metiltetrahidrofolato-Homocisteína S-Metiltransferasa/genética , Ferredoxina-NADP Reductasa/genética , Homocisteína/sangre , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Polimorfismo de Longitud del Fragmento de Restricción , Embarazo/sangre , Adolescente , Adulto , Alelos , Análisis de Varianza , Femenino , Ácido Fólico/sangre , Frecuencia de los Genes , Genotipo , Humanos , Ácido Metilmalónico/sangre , Reacción en Cadena de la Polimerasa , Embarazo/genética , S-Adenosilhomocisteína/sangre , S-Adenosilmetionina/sangre , Vitamina B 12/sangre , Adulto JovenRESUMEN
The frequency of X-chromatin was determined in pregnant women during the second trimester of gestation in order to establish possible correlations with the changes in steroid hormone levels occurring during this period and compare the curve with that for normal nonpregnant women. The mean frequency of X-chromatin in oral mucosa cells from a salivary suspension was 19.97% for the 24 patients studied, a statistically higher value than that obtained for nonpregnant women.
Asunto(s)
Frecuencia de los Genes , Embarazo/genética , Cromatina Sexual/ultraestructura , Cromosoma X/ultraestructura , Adulto , Análisis de Varianza , Femenino , Humanos , Mucosa Bucal/ultraestructura , Segundo Trimestre del EmbarazoRESUMEN
Procurou-se correlacionar ate que volume a perda sanguinea mentrual pode conduzir ao aparecimento de anemia ferropriva em mulheres. Para isso, determinou-se a quantidade de sangue perdido em 211 menstruacoes, pelo metodo de Hallberg & Nilsson. O volume medio foi de 40 ml e o uso de pilulas anovulatorias reduziu essa quantidade a 20,2 ml. A eliminacao de mais de 40 ml de liquido menstrual por ciclo coincidiu com quadros de anemia carencial, mostrando que o limite entre uma menstruacao normal e uma patologica e muito pequeno, nos casos estudados. Por outro lado a avaliacao subjetiva do volume mentrual feito pela propria paciente apresentou-se pouco confiavel