Collagenous Colitis

ABSTRACT Collagenous colitis is a very rarely recognized disease characterized clinically by watery diarrhoea and histologically by a broad, band-like deposition of collagen under the surface epithelium of the colon and rectum. Two cases of collagenous colitis are reported in this paper. After treatment of one of the patients with metronidazole, the symptoms cleared up and biopsy specimens from the colon showed regression of the pathological picture. The pathogenesis of the diarrhoea is discussed. The aetiological agent seems to be infectious, but is still unknown.     

Secretory effects of cholecystokinins on the isolated perfused porcine pancreas

Three different molecular forms of cholecystokinin (CCK-39, -33, and -8) were used in concentrations from 10^-11 to 10^-8 mol/l to stimulate the endocrine and exocrine secretion from the isolated perfused porcine pancreas. During perfusion with a glucose concentration of 7.5 mmol/1 CCK-39 in the highest concentration increased the insulin secretion slightly. No significant effect was observed at lower glucose concentrations (5.0 and 3.5 mmol/l). CCK-33 and -8 did not stimulate the secretion of insulin significantly, and neither of the cholecystokinins increased the secretion of glucagon and bicarbonate. All three molecular forms stimulated the secretion of fluid and protein in concentrations above 10^-11 mol/l in a dose-dependent manner and with equal potency. We conclude that the effect of these three cholecystokinins on the endocrine pancreas is without physiological significance, whereas all three are sufficiently potent to play a role in the control of pancreatic protein secretion.     

Charcoal surface-assisted catalysis of intramolecular disulfide bond formation in peptides

A mild and highly efficient method for intramolecular disulfide bond formation in peptides mediated by charcoal has been developed. Completion of the charcoal-assisted catalysis of disulfide bond formation took less than 6 h, testing a series of peptides with ring sizes varying from 2 to 17 amino acids. Kinetic studies revealed that the formation of small and large intramolecular disulfide cycles especially was accelerated significantly by the aid of charcoal as compared with dimethyl sulfoxide- and air-mediated cyclization. Oxygen adsorbed onto the charcoal surface is a prerequisite for disulfide bond formation. Thermodynamic studies showed that cyclization is accelerated by reduction of entropy of the peptides, most likely because of transient adsorption to the charcoal surface, thus resulting in a lower activation energy. © Munksgaard 1998.     

Prenatal ultrasound diagnosis of clubfoot

Five cases of congenital clubfoot diagnosed prenatally by ultrasound are reported. The incidence of clubfoot may be higher within an affected family and may be associated with other structural anomalies or chromosomal abnormalities. Identifying a clubfoot in utero should therefore alert the sonographer that other anomalies may be present and should lead to a detailed structural survey.