Chorea as a manifestation of epidural hematoma. Case report.
A child with epidural hematoma presented with choreiform movements which promptly resolved following the evacuation of the hematoma.
Adolescent↗
Biomedical subjects
J R Adler
Publications and source records attributed to J R Adler.
Evidence of prolactin receptors in the choroid plexus and a possible role in water balance in neonatal brain.
Tissue dehydration, including that of the brain, is a natural part of maturation. In the newborn it is accompanied by an acute salt water diuresis which is particularly pronounced in the premature infant. The decrease in cranial volume and fall in intracranial pressure to subatmospheric levels observed in premature infants after birth suggests that the brain shares in this process. Since fluid homeostasis is normally under hormonal control, the inordinate loss of fluid in the prematurely born may be attributable to a hormonal imbalance. The possibility that prolactin, a proven osmoregulatory hormone in submammalian species but not in mammals and primates, may have an important role in this process is suggested by recent evidence that prolactin regulates tissue water in fetal and newborn animals. If this hormone assists in the regulation of water and electrolyte content of the brain during the perinatal period then prolactin receptors might be expected at blood-brain and blood-CSF barriers. Our study with preterm, term and adult rabbits indicates that prolactin receptors are present and in much higher concentrations in the choroid plexus than in other tissues examined. Specific binding of prolactin to receptors on tissues normally is observed to increase with age. Since binding to the choroid plexus decreased with age it would suggest that the effect of prolactin on choroid plexus function may be more important during the perinatal than later stages of development.
Age Factors↗
Solubilization and characterization of a platelet membrane ADP-binding protein.
Previous studies have shown that platelet membranes bind radiolabeled ADP and have nucleoside diphosphokinase activity which transforms added ADP to ATP. In order to further characterize these reactions, the ADP-binding and nucleoside diphosphokinase activity of purified platelet membranes were solubilized by freeze-thaw injury followed by extraction with isotonic buffered saline. Up to 80% of membrane ADP-binding activity was solubilized along with 20% of the total membrane protein, a 4-fold purification. A Millipore filter binding assay was developed to detect the soluble binding protein using [3H]ADP as radioligand. Binding of [3H]ADP was rapid, reversible, saturable, and was destroyed by heat, trypsin digestion, and 1 mM N-ethylmaleimide. By Scatchard analysis, there was a single class of binding sites with a Kd of 3.8 x 10(-7) M. Unlabeled nucleotides competed with [3H]ADP with the following potency series: ATP = ADP greater than AMP greater than adenosine. The solubilized nucleoside diphosphokinase activity could be separated from ADP-binding activity by ultracentrifugation on 5 to 20% sucrose density gradients containing 0.6 M KCl suggesting that the activities reside on separate molecules. Hydrodynamic parameters were calculated for the binding protein by gel filtration and ultracentrifugation. The s20,w was 4.1, Stoke's radius 35 x 10(-8)cm, axial ratio (f/fo) 1.09, and the Mr = 61,000. The studies suggest that this platelet ADP-binding protein may act as the receptor for initiating ADP-induced aggregation and release.
Adenosine Diphosphate↗