OBJECTIVE: Our study objectives were (a) to investigate the heritability of age of menarche in twins, (b) to obtain the association between age of menarche and childhood factors, and reproductive events/behavior, (c) to examine whether or not having a male co-twin affects early/late menarche.
METHODOLOGY: A group of female-female identical (n = 108, 54 pairs), non-identical twins (n = 68, 34 pairs) and 17 females from opposite-sex twin sets were identified from twin registries of Malaysia and Iran. Genetic analysis was performed via two methods of Falconers' formula and maximum likelihood.
RESULTS: Heritability was found to be 66% using Falconers' formula and 15% using univariate twin analysis. Model analysis revealed that shared environmental factors have a major contribution in determining the age of menarche (82%) followed by non-shared environment (18%).
DISCUSSION: Result of this study is consistent with that of the literature. Timing of menarche could be under the influence of shared and non-shared environmental effects. Hirsutism was found to have a higher frequency among subjects with late menarche. There was no significant difference in age of menarche between females of opposite-sex twins and females of same-sex twins.
CONCLUSION: It is concluded that twin models provide a powerful means of examining the total genetic contribution to age of menarche. Longitudinal studies of twins may clarify the type of environmental effects that determine the age of menarche.
METHODS: Workers from all 143 registered abattoirs in 11 of 13 states in Malaysia were invited to participate in this cross-sectional study. Participants were interviewed to ascertain information on illness and activities performed at the abattoir. A serum sample was obtained to test for Nipah virus antibody.
RESULTS: Seven (1.6 %) of 435 abattoir workers who slaughtered pigs versus zero (0%) of 233 workers who slaughtered ruminants showed antibody to Nipah virus (P = 0.05). All antibody-positive workers were from abattoirs in the three states that reported outbreak cases among pig farmers. Workers in these three states were more likely than those in other states to have Nipah antibody (7/144 [4.86%] versus 0/291 [0%], P < 0.001) and report symptoms suggestive of Nipah disease in pigs admitted to the abattoirs (P = 0.001).
CONCLUSIONS: Nipah infection was not widespread among abattoir workers in Malaysia and was linked to exposure to pigs. Since it may be difficult to identify Nipah-infected pigs capable of transmitting virus by clinical symptoms, using personal protective equipment, conducting surveillance for Nipah infection on pig farms which supply abattoirs, and avoiding handling and processing of potentially infected pigs are presently the best strategies to prevent transmission of Nipah virus in abattoirs.
METHODOLOGY: This was a prospective cohort study. Shortly after birth, cranial ultrasonography was carried out via the anterior fontanelles of 70 normal control infants and 104 asphyxiated infants with a history of fetal distress and Apgar scores of less than 6 at 1 and 5 min of life, or requiring endotracheal intubation and manual intermittent positive pressure ventilation for at least 5 min after birth. Neurodevelopmental assessment was carried out on the survivors at 1 year of age.
RESULTS: Abnormal cranial ultrasound changes were detected in a significantly higher proportion (79.8%, or n = 83) of asphyxiated infants than controls (39.5%, or n = 30) (P < 0.0001). However, logistic regression analysis showed that only three factors were significantly associated with adverse outcome at 1 year of life among the asphyxiated infants. These were: (i) decreasing birthweight (for every additional gram of increase in birthweight, adjusted odds ratio (OR) = 0.999, 95% confidence interval (CI) 0.998, 1.000; P = 0.047); (ii) a history of receiving ventilatory support during the neonatal period (adjusted OR = 8.3; 95%CI 2.4, 28.9; P = 0.0009); and (iii) hypoxic-ischaemic encephalopathy stage 2 or 3 (adjusted OR = 5.8; 95%CI 1.8, 18.6; P = 0.003). None of the early cranial ultrasound changes was a significant predictor.
CONCLUSIONS: Early cranial ultrasound findings, although common in asphyxiated infants, were not significant predictors of adverse outcome during the first year of life in asphyxiated term infants.