Esthesioneuroblastoma in a young child. Case report

Esthesioneuroblastoma is an uncommon malignant neoplasm that arises from olfactory mucosa, often with intracranial extension.A case report of the youngest victim in the literature (2-year-old boy) is presented.     

105Changes in Nitric Oxide Levels After Deep Dermal injury in the Female,Red Duroc Pig (FRDP)

Introduction : Hypertrophic scar is a devastating sequel to burns and other tangential skin injuries. It follows deep dermal injuries and does not occur after superficial injuries. Nitric oxide (NO) plays many important roles in wound healing from inflammation to scar remodeling. Studies have shown that expression of nitric oxide synthase and nitric oxide production are decreased in human hypertrophic scar. However little is known about NO involvement in the early stages of hypertrophic scarring, because of the lack of an animal model. It was recently reported that the female red Duroc pig (FRDP) makes thick scar, which is similar to human hypertrophic scar. We hypothesized that NO production in wounds on the female, red Duroc pig is similar to that of human hypertrophic scar and that NO involvement in deep wounds is different from that in superficial wounds. Methods : Superficial (0.015” to 0.030”) and deep (0.045” to 0.060”) wounds were created on the backs of four FRDPs. Biopsies were collected at weeks 1.5, 4, 8 and 21 post wounding including samples of uninjured skin. Nitric oxide levels were measured with the Griess reaction assay and normalized with tissue protein level. Results : Superficial wounds healed with an invisible scar whereas the deep wounds healed with scar resembling mild hypertrophic scar. The thickness of the scars from the deep wounds was significantly greater than uninjured skin and healed superficial wounds (p < 0.01). NO levels were increased at 1.5 weeks in deep wounds compared to superficial wounds and uninjured skin (p < 0.05). At 8 weeks, NO levels in deep wounds had returned to the level of uninjured tissue and superficial wounds. By 21 weeks, NO levels had decreased significantly when compared to superficial wounds (p < 0.01). There were no differences in NO levels between uninjured skin and superficial wounds at any time point (p > 0.05). Conclusions : NO production is similar in late, deep wounds on the female, red Duroc pig to that reported in the literature for human hypertrophic scar further validating this animal model. NO production is quite different after deep wounds as compared to superficial wounds in the FRDP. Early elevation in nitric oxide production might account for excessive inflammation in deep wounds that become thick scars in the FRDP. Nitric oxide regulators and effects at early stages of scar formation should be elucidated further and the FRDP appears to be a useful model.     

Enamel structure and composition in the tricho-dento-osseous syndrome

Tricho-dento-osseous syndrome (TDO) is an autosomal dominant disorder characterized by curly hair, hypoplastic enamel, taurodontism, and dense bone. The purpose of this investigation was to characterize the enamel defects in a TDO population in North Carolina. Twelve TDO teeth and 12 normal teeth were examined. The enamel thickness was decreased in all TDO teeth ranging from having no enamel to about 60% the thickness of normal teeth. Half of the TDO teeth had primarily prismless enamel while the remainder had at least occasional areas of prismatic enamel. TDO enamel crystallites appeared similar to normal crystallites with TEM. The mineral per volume of TDO enamel (n = 9) (68.5%) was significantly less, on average, compared with normal enamel (n = 8) (84.5). The genetic mutation responsible for the TDO phenotype results in alteration of a developmental pathway(s) common to hair, teeth and bone. This further illustrates that these embryologically diverse tissues share common developmental controls at the molecular level.     

Genetic linkage of the tricho-dento-osseous syndrome to chromosome 17q21

Tricho-dento-osseous syndrome (TDO), MIM# 190320, is transmitted as a highly penetrant autosomal dominant trait that is characterized by variable clinical expression. The principal clinical features include kinky/curly hair in infancy, enamel hypoplasia, taurodontism, as well as increased thickness and density of cranial bones. Possible genetic linkage has been reported for TDO with the ABO blood group locus, but the gene defect remains unknown. We have identified four multiplex families (n = 63, 39 affected, 24 unaffected) from North Carolina segregating TDO. We previously have excluded a major locus for TDO in the ABO region for these families. Utilizing a genome-wide search strategy, we obtained conclusive evidence for linkage of the TDO syndrome locus to markers on chromosome 17q21 (D17S791, Z max = 10.54, Theta = 0.00) with no indication of genetic heterogeneity. Multipoint analysis suggests the TDO locus is located in a 7 cM chromosomal segment flanked by D17S932 and D17S941. This finding represents the first step towards isolation and cloning of the TDO gene. Identification of this gene has important implications for understanding normal and abnormal craniofacial development of hair, teeth and bone.      

Neuropharmacological assessment of potential dopamine D4 receptor-selective radioligands

Radiolabeled dopamine D4 receptor-selective agents ([3H]1-benzyl-4-[ N-(3-isopropoxy-2-pyridinyl)-N-methyl]-aminopiperidine maleate; [3 H]PNU-101958. and [125I]1-[4-iodobenzyl]-4-[ N-(3-isopropoxy-2-pyridinyl)-N-methyl]-aminopiperidine; [125I]RBI-257) were prepared and characterized. With D4.2- and D2L receptor-transfected cell membranes, [3H]PNU-101958 showed high dopamine D4 receptor affinity and selectivity, and potent inhibition by dopamine D4 receptor-selective compounds. However, its binding with rat brain homogenates showed little regional selectivity, and pharmacology inconsistent with selective dopamine D4 receptor labeling. Autoradiography indicated partial displacement of [3H]PNU-101958 by unlabeled dopamine D4 receptor ligands without regional selectivity, and lack of selective labeling with [125I]RBI-257. The results encourage further efforts to develop better dopamine D4 receptor-selective radioligands.     

3H]beta-CIT: a radioligand for dopamine transporters in rat brain tissue

[3H]2-beta-carbomethoxy-3-beta-[4'-iodophenyl]tropane (beta-CIT) was prepared and evaluated. With rat forebrain tissue, [3H]beta-CIT showed high affinity for dopamine transporters (DAT), with selectivity for DAT over norepinephrine transporters, but not serotonin transporters, as well as DAT-stereoselectivity with beta-CIT, amphetamine and methylphenidate. Affinity and selectivity for 53 compounds assayed with [3H]beta-CIT and standard DAT radioligand [3H]GBR-12935 were highly correlated (r0.95). [3H]beta-CIT is proposed as a useful, high-affinity DAT radioprobe.     

TREATMENT OF PALMOPLANTER HYPERHIDROSIS BY IONTOPHORESIS

Twenty-seven patients with idiopathic palmoplanter hyperhidrosis were treated with Iontotherapy over a one year period. In twenty-four cases there was a good response but maintenance therapy was required every 3-4 weeks.KEY WORDS: Iontophoresis, Palmoplanter hyperhidrosis