Abnormal oral vascular network pattern geometry: a new clinical sign of down syndrome.

Down syndrome is a leading genetic cause of mental retardation. Here, we show high fractal dimensions and Lempel-Ziv complexity and lower minimum path fractal dimension (P < or = .0006) for the oral vascular networks of patients (n = 14) and their unaffected parents. This newly recognized sign may provide a useful phenotypical marker for identifying couples potentially at risk for offspring with Down syndrome.

Congenital oral mucosal abnormalities in true umbilical cord knots.

OBJECTIVE: The pathogenesis and clinical significance of true umbilical cord knots remain controversial. Here, we tested the hypothesis of the presence of congenital oral mucosal changes in newborns with true umbilical cord knots. STUDY DESIGN: Seven consecutive infants with true umbilical cord knots and 50 gestational age- and sex-matched controls were enrolled. The proportion of oral frenulum abnormalities and the two-dimensional vascular network geometry [fractal dimension, D, at two scales: D(1-46), and D(1-15), with the relative Lempel-Ziv complexity, (L-Z)], were analyzed. RESULTS: Infants with true umbilical cord knots showed significantly higher proportions of mandibular frenulum agenesis compared to controls (p = 0.000006). The oral vascular networks of these infants exhibited a significantly higher D(1-46) and D(1-15) (p < 0.0001, respectively), and higher L-Z values (p < 0.0001) than control networks. CONCLUSION: These findings indicate the presence of significant congenital oral mucosal changes in newborn infants with true umbilical cord knots, thus suggesting a previously unrecognized association between true umbilical cord knots and a subclinical extracellular matrix disorder.

Nephrogenic adenoma of the urethra: an unusual cause of hematuria in the child.

The authors describe a 9-year-old boy who had an accident with his bicycle. He presented with hematuria a few weeks later, and cystoscopy results showed a polypod lesion near the veru montanum. The lesion was resected, and histologic examination showed a nephrogenic adenoma (NA), which recurred 6 years later with hematuria. NA is a rare lesion in a child's urethra and can be a source of hematuria.

Structural, functional and circulatory placental changes associated with impaired glucose metabolism.

OBJECTIVE: To investigate associations between structural, functional and circulatory placental changes in pregnancies complicated by impaired glucose metabolism. DESIGN: Umbilical artery (UA) blood flow resistance was measured by Doppler velocimetry in 21 gravidae with diabetes/impaired glucose tolerance (IGT) and 10 healthy gravidae. Umbilical and placental vessel segments were incubated for determination of prostacyclin and thromboxane synthesis, and tissues histologically examined. Non-parametric statistical tests at a two-tailed P<0.05 were used. RESULTS: Placental lesions were more common in diabetes/IGT and, although not being an uniform finding, in general associated with a higher vascular synthesis of thromboxane and/or lower prostacyclin/thromboxane synthesis ratio. As an exception, ischemic villitis was associated with a higher ratio and higher UA flow resistance. CONCLUSIONS: Placental lesions are associated with an altered vascular prostanoid synthesis in diabetes/IGT, but not until structural signs of ischemia develop is a rise of UA blood flow resistance detected.

PPAR expression and function during vertebrate development.

The peroxisome proliferator activated receptors (PPARs) are ligand activated receptors which belong to the nuclear hormone receptor family. As with other members of this superfamily, it is thought that the ability of PPAR to bind to a ligand was acquired during metazoan evolution. Three different PPAR isotypes (PPARalpha, PPARbeta, also called 6, and PPARgamma) have been identified in various species. Upon binding to an activator, these receptors stimulate the expression of target genes implicated in important metabolic pathways. The present article is a review of PPAR expression and involvement in some aspects of Xenopus laevis and rodent embryonic development. PPARalpha and beta are ubiquitously expressed in Xenopus early embryos but become more tissue restricted later in development. In rodents, PPARalpha, PPARbeta and PPARgamma show specific time- and tissue-dependent patterns of expression during fetal development and in the adult animals. PPARs are implicated in several aspects of tissue differentiation and rodent development, such as differentiation of the adipose tissue, brain, placenta and skin. Particular attention is given to studies undertaken by us and others on the implication of PPARalpha and beta in rodent epidermal differentiation.