Familial Band-shaped Nodular Keratonathy

A family is reported in which two brothers have a bilateral, symmetrical corneal disorder characterized by small yellowish to ambercolored globules arranged in a band-shaped configuration in the central superficial layers of the cornea. The globules have a similar clinical appearance to those found in Bietti's “band-shaped nodular dystrophy,” a keratopathy that is nonfamilial, has an onset later in life, and initially involves the peripheral cornea. Light and electron microscopic studies of corneal tissue obtained from the proband showed that the globular deposits autofluoresce, that they stain black with Verhoeff's elastic stain, and that they correspond to an electron-dense material found within corneal epithelial cells and keratocytes and within the extracellular tissues of the anterior cornea. A third, younger brother appears to have the early corneal signs of the condition. Unlike the condition described by Bietti, the keratopathy we report is unique in its familial nature, early onset in life, and initial, marked central corneal involvement.     

Fetal renal maturation. Studies on urinary beta 2 microglobulin the neonate

Beta 2 microglobulin [B2m] and creatinine [Cr] concentrations were measure in the urine of 27 newborn infants. At birth, urinary [B2m] and [B2m]/[Cr] ratios were significantly lower in infants born beyond 36 weeks' gestation. Serial measurements, postnatally, showed a progressive decrease in the urine [B2m]/[Cr] ratio of infants born prematurely. These findings suggest an increase in tubular uptake of B2m with increasing gestational and postnatal age. The current findings tend to support the hypothesis that the decrease in [B2m] observed in amniotic fluid beginning at approximately 36 weeks' gestation reflects maturation of fetal proximal renal tubular function.     

Preparative purification of the rat mast cell chymase. Characterization and Interaction with granule components

The rat mast cell granule chymotrypsinlike enzyme was purified to homogeneity from 1 M NaCl solubilized membrane and granule-rich fractions of concentrated rat peritoneal mast cells by a preparative technique utilizing chromatography on Dowex 1, filtration on Sephadex G-75, and affinity chromatography with D-tryptophan methyl ester. Acid disk gel electrophoresis of the purified chymase disclosed a single stained band with activity being eluted from a replicate sliced gel in the same region. SDS-polyacrylamide gel electrophoresis of purified protein gave a single stained band that did not change in position with reduction and alkylation. Mast cell chymase is thus a cationic protein of 25,000 mol wt composed of a single polypeptide chain. The apparent K(m) of the chymase for BTEE was 1.5 x 10(-3) M and the V(max) was 67.8 μmol/min per mg. The enzyme was inhibited by TPCK and not by TLCK. The chymase complexed with native macromolecular rat mast cell heparin in molar ratios of 12:1 and 16:1, and complete heparin uptake occurred at a 40:1 ratio of chymase to heparin. Chymase activity was partially masked by combination with heparin in the isolated granule or experimental chymase-heparin complex, and soluble purified chymase was inhibited by concentrations of 5-HT comparable to those present in mast cells. It is therefore possible that the active site of chymase in the mast cell granule is largely masked by the combined effects of macromolecular heparin and 5-HT.