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B Beiguelman

Publications and source records attributed to B Beiguelman.

At least 19 recordsLinked to original sources
PubMed1996

Investigation on seasonality of twin births in Brazil.

The hypothesis of seasonality of twin births was investigated in two important maternity hospitals in the State of São Paulo, Brazil. The study included 1,386 twin births that occurred among 154,699 deliveries from 1984 to 1993. No evidence of seasonality has been detected either for the twin birth rate considered as a whole or for dizygotic twinning rate. The distributions of these rates fitted well sinusoidal regression curves but the cyclic trend did not correspond to any specific season.

Analysis of Variance↗
PubMed1996

Twinning rate in a southeastern Brazilian population.

The twinning incidence from 1984 to 1993 was investigated in Campinas, State of São Paulo, Brazil and the analyzed data were combined with previous series from the same population. This study has shown that the mean annual incidences and the standard deviations for DZ, MZ and DZ plus MZ twins for the period of 1984 to 1993 are estimated respectively as 4.7 +/- 0.92, 4.1 +/- 1.11, and 8.8 +/- 0.87 per 1,000. In the same period the mean annual incidence of triplets was 0.15 +/- 0.16. It was also shown that the incidence of DZ twins is steadily decreasing since 1925, while the incidence of MZ pairs, after a period of decline is increasing since the sixties, due perhaps to the widespread use of oral contraceptives. Concerning the twinning rate as a whole, it has been shown that its declining trend has disappeared over the last few years.

Brazil↗
PubMed1995

Annual variation of sex ratio in twin births and in singletons in Brazil.

The annual variation of the sex ratio (SR) of 1385 twin births was analyzed and compared to that of 85909 singletons. These births referred not only to live births but also to stillbirths in two southeastern Brazilian maternity hospitals from 1984 to 1993. While the annual variation of the SR of singletons was very small, that of twin births was extremely high, due to the significant heterogeneity of the annual data. It is suggested that the large SR annual variation of the twin birth might be a consequence of the variation of male or female monozygotic twins. The hypothesis that twin births show a lower sex ratio than singletons could be supported by the present data.

Adult↗
PubMed1995

The genetic epidemiology of leprosy in a Brazilian population.

Data on leprosy patients have been obtained from the Dispensary of Leprosy of Campinas, São Paulo, where records on practically all cases of leprosy in the Campinas area during the period 1960-70 are filed. The whole sample comprises 10,886 individuals, distributed among 1,568 families. Complex segregation analysis was utilized to determine the nature of the genetic factors that may operate on leprosy and its subtypes. The results suggest the presence of a recessive major gene controlling susceptibility to leprosy per se, with frequency of approximately .05, although there are deviations from the expected Mendelian segregation proportions. Possible etiologic heterogeneity was examined by considering two subtypes separately: for lepromatous leprosy and tuberculoid leprosy there are suggestions for a segregating major effect; however, Mendelian transmission could not be demonstrated in either case. Therefore, there is no evidence to suggest unique genetic determinants for leprosy subtypes.

Adolescent↗
PubMed1989

Decline of the twinning rate in Brazil.

The twinning rate during a twenty-year period (1965-1985) was investigated at five-year intervals in four Brazilian hospitals. During this period the twinning rate has decreased significantly (from 10.68% to 8.11%), being highly negatively correlated with the five-year intervals (r = -0.97). This change was due mainly to the decline in dizygotic twinning, since the incidence of DZ twins has fallen from around 7% in 1965 to around 3.6% in 1985. The detected decline in DZ twinning seems to be due to the remotion of the fertility advantage of the more fecundable DZ twin-prone women by the introduction of effective birth control at the present, while some other mechanisms are causing the decline irrespective of the type of twinning.

Brazil↗
PubMed1989

Heritability of quantitative orbital traits.

We conducted a study of 63 couples and their 242 normal children from northeastern Brazil (no facial malformations or deformities) to evaluate the heritability of 4 quantitative traits of the orbital region adjusted by covariance for sex, age, (age)2, sex x age, and sex x (age)2. The heritability is estimated as 0.514 for the mean horizontal diameter of the palpebral fissures, 0.454 for the interpupillary distance, 0.390 for the internal intercanthal distance, and 0.337 for the external intercanthal distance. The heritability of the first principal component of the orbital region is estimated as 0.418.

Adolescent↗
PubMed1985

Chromosomal aberrations in cultures of skin fibroblasts of leprosy patients.

A search for structural and numerical chromosomal aberrations was made on metaphases obtained by culturing in vitro skin fibroblasts of 16 leprosy patients (10 lepromatous, 2 borderline, and 4 tuberculoid cases) and 2 healthy individuals used as controls. The data were analyzed taking into account sex, age, race, form of leprosy, bacterial index, type of therapy, and age of the fibroblast cultures. Structural chromosomal aberrations are the only type of chromosomal abnormality that may be accepted as significantly increased in the skin fibroblasts of leprosy patients who are under treatment with dapsone alone or with combined therapy.

Adolescent↗
PubMed1985

Histology of the Mitsuda reaction of healthy adults with no known contacts with leprosy patients.

Mitsuda tests were performed on 100 healthy adult Brazilian males unrelated consanguineously to leprosy patients and with no known contacts with this disease. Three lepromatous patients served as negative Mitsuda controls. The lepromin employed was from Mycobacterium leprae-infected armadillo tissue prepared according to WHO standards. Clinical response to the lepromin inoculation was graded according to the recommendations of the VI International Leprosy Congress held in Madrid (1953). The histological reaction was graded according to the authors' criteria based on the intensity of the granulomatous response. The clinically positive (77), the doubtful (19), and 1 out of 4 clinically negative Mitsuda reactors disclosed histologically positive reactions of different degrees of intensity. A significant association between the clinical and histological readings of the Mitsuda reaction was demonstrated when the results of both readings were grouped in two classes: negative and non-negative. However, the different degrees of the histologically positive lepromin reactions were distributed at random among the clinically positive Mitsuda reactors. The frequency of histologically negative Mitsuda reactors observed among the healthy subjects who had no known contacts with leprosy patients (3%) was significantly low when compared to the frequencies reported in the pertinent literature concerning healthy contacts of patients with Hansen's disease.

Adult↗
PubMed1984

NADH-methemoglobin reductase and methemoglobinemia among leprosy patients.

The NADH-methemoglobin reductase activity as well as hemoglobin and methemoglobin levels were investigated in blood samples of 182 adult leprosy patients and 137 Brazilian army enlisted men. The level of sulfones in the blood samples of the leprosy patients, all of them ingesting a daily dose of 100 mg dapsone, was also investigated. The mean value of NADH-methemoglobin reductase activity exhibited by the leprosy patients did not differ from that observed among the healthy individuals. However, the variance of the former group was significantly higher than that observed among the healthy subjects. As a consequence, the proportion of individuals showing a partial deficiency of NADH-methemoglobin reductase was significantly higher among the leprosy patients (22.5%) than among the healthy individuals (2.9%). The activity of this enzyme among the leprosy patients was negatively correlated to the hemoglobin level and slightly positively correlated to age. The concentration of methemoglobin among the leprosy patients was slightly but significantly higher as compared to the healthy individuals. The increase of the methemoglobin level among the leprosy patients was influenced by the amount of sulfones in the blood. However, no case in which dapsone was ingested in a daily dose of 100 mg presented the signs or symptoms of toxic methemoglobinemia.

Adult↗
PubMed1983

[Thalassemia and Hansen's disease].

The beta-thalassemia trait was investigated among 165 Brazilians who were unmixed Italian descendants (80 Virchowian patients and 85 normal controls, composed of universitary students). The frequency of the beta-thalassemia trait was 6.25% among the Virchowian patients and 5.88% in the control group. In spite of the similar geographical distribution of both hanseniasis and the gene for beta-thalassemia in Asia, the present data does not support the hypothesis that hanseniasis might have contributed to maintain high prevalence of this allele by selection favouring beta-thalassemia trait.

Female↗