Molecular basis for pseudo vitamin D-deficiency rickets in the Hannover pig.

The molecular basis for pseudo vitamin D deficiency rickets (PDDR) in the Hannover pig model was determined in the current study. Consistent with the inability of Hannover PDDR pigs to maintain ambient levels of 1,25-dihydroxyvitamin D (i.e., 1,25D), the bioactivation enzyme cytochrome P450C1 (or CYP27B1) was determined to contain coding-region deletions that rendered the enzyme ineffective due to frame-shift mutations and expression of a premature termination codon. Expression levels of P450C1mRNA were up-regulated in response to the low-1,25D high-parathyroid hormone state of the PDDR animals. In a complementary manner, cytochrome P450C24 mRNA was not detectable in PDDR pigs. Two different deletions were detected within the Hannover pig strain in which the P450C1 coding region contained either 173 bp or 329 bp deletions that resulted in the expression of non-sense products beginning within the I-helix region and extending through the truncated C-terminal domains. The boundaries for the deletion segments aligned with derived mRNA processing sites. This observation was consistent with an mRNA processing error as the causative factor for the coding-region deletions. Based upon the expression of a non-functional P450C1 enzyme, the Hannover pig model for PDDR was determined to be identical to the human disease in which enzyme-inhibitory mutations are the molecular basis for the calcium disorder.

Decreased developmental stability as assessed by fluctuating asymmetry of morphometric traits in preterm infants.

Fluctuating asymmetry (FA) of 8 morphometric traits was studied in 113 preterm infants (26-36 wk of gestation), 103 term infants (37-41 wk), and their respective parents. With 3 different measures of FA, the highest values were obtained from extremely preterm infants (26-29 wk), and the lowest from the group of term infants. The estimates of FA values among parents, particularly mothers, showed a similar, albeit less pronounced, trend. Multiple regression analysis of individual mean FA values, calculated in infants for the 8 studied bilateral traits, documented a significant inverse correlation with gestational age and with the health status of the infants and their mothers, as well as a positive correlation with the mothers' mean FA values.

Some biological and social factors of risk associated with the birth of pre-term infants.

The main purpose of the present study was to evaluate the effects of factors associated with spontaneous pre-term births so that the high risk woman could be identified before or at early stages of pregnancy. For this purpose, we have compared the measurements of 21 anthropometric traits and mean fluctuating asymmetry over 8 bilateral anthropometric traits, as well as age, occupation, education, previous obstetric history, complications during pregnancy, medicines received during and after pregnancy and some others in women who delivered babies of short (26-36 wk, n = 113 ind.) and normal gestational age (n = 103). Diseases and mean fluctuating asymmetry of eight morphological traits in the newborn infants themselves were also studied. Both univariate and multivariate analyses were carried out and these were in agreement, showing a highly significant increase in the morbidity rate (especially of respiratory diseases) among pre-term infants and in complications during pregnancy in their mothers. Among other variables associated with the current pre-term birth were previous spontaneous pre-term births, suggesting their special risk value. The estimate of the sib correlation in gestational age on the liability scale was about 0.63. Spearman and Pearson correlations in gestational age for siblings were 0.34 and 0.31, respectively.