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Biomedical subjects

R Garza-Chapa

Publications and source records attributed to R Garza-Chapa.

29 records · Page 2Linked to original sources
PubMedDate not supplied

The effect of diphenylhydantoin on the frequency of micronuclei in bone-marrow polychromatic erythrocytes of mice.

Using the micronucleus test to evaluate the mutagenic effect of 5,5-diphenylhydantoin (DPH) on bone marrow polychromatic erythrocytes, male Balb-C mice were treated with the drug in single and multiple injection tests. A significant increase in the frequency of micronucleated polychromatic erythrocytes (MPE), P less than 0.05, was found when the mice received a single injection of DPH at doses of 0.5 and 1.0 mg/kg, and this frequency did not increase at higher doses. When mice were treated 3 times, at 24-h intervals, with 1.0 mg/kg of DPH, a significant increase in MPE was also observed (P less than 0.05) but this was lower than when they received a single injection of the same dose. A cytotoxic effect of NaOH, 0.1 N, which was used as solvent, was also observed either when alone or when DPH (1.0 mg/kg) was injected 3 times. This effect was comparable to the one produced by mitomycin C (MMC) at a dose of 0.5 mg/kg.

Animals↗
PubMedDate not supplied

Birth order, sibship size, and risk of epilepsy.

We examined the relation between epilepsy and birth order, using data on 1,950 probands with epilepsy and 4,636 of their full siblings without epilepsy from the Epilepsy Family Study of Columbia University. The proportion of first-born individuals appeared to be higher among probands with epilepsy than among their unaffected siblings, but this relation disappeared after we controlled for the confounding effect of sibship size. With sibship size controlled, the proportion of first-born individuals was similar to that in unaffected siblings for probands with idiopathic/cryptogenic epilepsy, generalized and partial onset seizures, and all ages at onset of epilepsy. Probands with remote symptomatic epilepsy had higher birth orders than their unaffected siblings, even after we controlled for sibship size.

Adolescent↗
PubMedDate not supplied

[Effect of sodium diphenylhydantoin on sister chromatid exchange frequency in mice].

In order to analyze the effect of the anticonvulsant diphenyl hydantoin (DPH) over the frequency of sister chromatid exchanges (SCE) in vivo, Balb-C mouse 8-12 weeks old, males and females, were injected intraperitoneally with a single dose and three different concentrations: 1, 10 and 20 mg/Kg, as negative and positive control, we used physiological serum and mitomycin-C respectively that were injected in the same way. Twenty five metaphases were analyzed per individual in the slide with the differential staining of sister chromatid, we found a light, but significantly increase, in the frequency of SCE in the concentrations of 10 and 20 mg/Kg when they were compared with the ones obtained for the negative control. In the males was observed a positive correlation in the levels of ICH when the doses of DPH were increased.

Animals↗
PubMedDate not supplied

[Relative frequency of glucose-6-phosphate dehydrogenase deficiency in jaundiced newborn infants in the metropolitan area of Monterrey, Nuevo León].

In order to estimate the frequency of G6PD deficiency in the icteric population of the Monterrey metropolitan área (MMA), in the state of Nuevo León, there were studied 829 newborn males were studied. It was found that 13 subjects were deficient of this enzyme, that is equivalent to a frequency of 1.57% and when this frequency was compared with the one that was found an a previous study in a random sample of newborn males (0.66%) no statistical difference was observed, but it was estimated that the icteric newborn males have a relative risk of 2.34 times higher than the population in general to be a G6PD deficient, and this fact suggests the necessity to establish this screening test as a routine for all icteric newborn males, in order to have an opportune detection and an appropriate counselling.

Adult↗
PubMedDate not supplied

[Frequency of color blindness and glucose-6-phosphate dehydrogenase enzyme deficiency in non-industrialized populations in the state of Nuevo León, México].

In order to know if there would be genetic structural differences among non industrial and industrial populations, two genetic markers were studied: color-blindness (CPC) and glucose-6-phosphate dehydrogenase deficiency (G6PD), in students, males and females that were resident in five non industrial populations in the State of Nuevo Leon. The results were compared with the information for industrial zone from the Monterrey Metropolitan area (AMM). It was found that the frequencies of CPC and G6PD in non industrial populations (2.57 and 0.00 per cent), were lower than the ones in the industrial AMM (4.0 and 0.66 per cent), probably as a result that in the first populations, with minor urbanization, the main factors that influence are: natural selection, interacial mixed or genetic drift and the second population is the immigration, since 1940 to present time, of Mexican populations with greater influence from the Indians and Africans.

Adolescent↗
PubMedDate not supplied

[Activity of ribosomal genes and the association with acrocentric chromosomes in trisomy 21 and habitual abortion].

The frequency of silver stain of the nucleolus organizer regions (NOR's) an indicator of the transcriptional activity of the DNAr, and the frequency of the association between acrocentric chromosomes (A.A.C.), possible indicator of the non-disjunction risk, were studied in the chromosomes in metaphase of eight married couples with regular 21 trisomy children, five couples that have had consecutive miscarriages and fifteen control normal persons, eight men and seven women. In this three groups the mean age was 30 years and they were compared according to sex. Another seven couples, with a mean age of 52 years also parents of 21 trisomic were compared against the group of young parents of 21 trisomics in order to analyze the age effect. Moreover there were studied the trisomic children of eight of the above couples in order to find out the effect of the supernumerary 21 chromosome. In all the groups the correlation coefficients between the frequency of NOR's-Ag+ and the A.A.C. were determined. It was found that the young group of parents of trisomic and the couples with consecutive miscarriages, both men and women, had a significant increased frequencies of NOR's-Ag+ and A.A.C. in comparison to controls. In the parents of trisomic, either men or women it was found a significant diminished level in the frequency of NOR's-Ag+ when the age increased, meanwhile raise in the frequency of A.A.C. with the increase of age was observed only in the women. A positive correlation between the frequencies of NORs-Ag+ and A.A.C. was found in the women of the control group and in the young mothers of trisomic.(ABSTRACT TRUNCATED AT 250 WORDS)

Abortion, Habitual↗
PubMedDate not supplied

[Deficiency of glucose-6-phosphate dehydrogenase in a family].

The erytrocyte glucose-6-phosphate deshydrogenase (G6PD) identification and activity were determinated in all member of a family, which was selected because one of the sons showed the clinical signs of hemolitic anemia due to G6PD deficiency and this was confirmed by qualitative fluorescent test, enzyme activity quantification and electrophoretic runs. It was found that two clinically healthy brothers are G6PD deficients and that the mother and one sister are carriers of this enzimatyc defect of the A--variant. As an antecedent it was found that the propositus mother received chloramphenicol treatment for ten days during the first three months of pregnancy. The advantages of the opportune enzymatic studies, with the objective to avoid hemolitic crisis in those G6PD deficient persons, are commented.

Adolescent↗
PubMedDate not supplied

[Preferences on family composition among youngsters from Monterrey, Mexico].

In order to evaluate the effect of social and biological factors on family size (FS) and secondary sex ratio (SSR) in the families that they would desire to procreate as well as in the ones to which they belong, 1,518 unmarried persons of both sexes, students and workers, who reside in the metropolitan area of Monterrey, Mexico were interviewed. It was found that the average FS desired by the unmarried males and females, independently of their socioeconomic level and years of schooling, were 3.19 and 3.04, which are lower than half the FS of 6.81 observed in the families to which they belong. Both males and females in all the socioeconomic levels and years of schooling, would desire to procreate a larger number of male children: SSR of 0.576 and 0.524, which are higher than the 0.498 observed in the families to which they belong. Also they manifested a strong preference for the birth order of the sex of their children, being of males for the first (SSR of 0.924 and 0.838) and of females for the second (SSR of 0.301 and 0.269). The fact that all children would be of the same sex did not change the desired FS in about 80% of the persons, but in the remainder 20% the desired FS would be increased to an average of five children. In order to reduce the growth rate it would be convenient to offer special counseling on family planning to these persons. In conclusion, the obtained information indicates that aside from the socioeconomic, cultural and biological factors, probably the family planning programs have had a positive influence on the persons that in the near future will start their reproductive stage, and it is possible to anticipate a reduction on the growth rate for the next generation.

Adult↗