Angiola Fontanella

Isolation and characterization of dipeptidyl peptidase IV from human meconium: Functional role of β-casomorphins

Dipeptidyl aminopeptidase IV (DAP‐IV) (EC 3.4.14.1) was purified from meconium particles sedimenting at 105000 × g. Its molecular properties and activity on synthetic and natural substrates (casomorphin and procasomorphin) were investigated.

Serum hyaluronic acid and laminin in children with chronic hepatitis B

Objective: To evaluate whether hyaluronic acid and laminin PI serum concentrations reflect the presence of liver fibrosis and/or cirrhosis in children with chronic hepatitis B infection. Design and patients: Serum concentrations of hyaluronic acid and laminin PI were correlated with several clinical, biochemical and histological parameters in 54 children (mean age, 7.7 years) with chronic hepatitis B, in 13 healthy carrière, and in 18 age- and sex-matched controls. Results: Levels of hyaluronic acid in patients with cirrhosis were significantly higlher than in controls and patients without cirrhosis. Concentrations above 100μgfl were observed only in children with cirrhosis, but sensitivity was low. Serum concentrations of laminin PI in patients with cirrhosis were significantly higher than in controls, but overlapped with values in the other patient subgroups. The extent of fibrosis, assessed by computerized histomorphometry, correlated significantly with serum concentrations of both hyaluronic acid and laminin PI; no cut-off value discriminated between small and large lesions. The concentrations of hyaluronic acid and laminin P1 were highest in patients with marked capillarization of liver sinusoids at electron microscopy and/or thickened lesser omentum at sonography, two alleged features of portal hypertension. Conclusion: The correlation between serum concentrations of hyaluronic acid and laminin PI and the presence of liver fibrosis and/or cirrhosis in children with chronic hepatitis B virus infection was statistically significant but clinically limited.

Fulminant Hepatitis B and Neonatal Hepatitis with Galactosemia-Like Presentation

*Departments of Pediatrics and Pathology, II Faculty of Medicine, University of Naples, Italy. Correspondence to: Dr. Pietro Vajro, Dipartimento di Pediatria, II Facolta’ di Medicina, Universita’ di Napoli, Via S. Pansini, 5-80131 Napoli, Tel: 081/5467472 or 7463385. It has often been emphasized that the diagnosis of mild cases of galactosemia may be overlooked for weeks or months.1,2 Since the early course of galactosemia often includes cholestasis, it has been recommended that any jaundiced infant should be rapidly evaluated at the bedside for the presence of urinary non-glucose reducing substances in order to avoid the severe consequences of delayed diagnosis and treatment.3-’

Effect of prednisone on DR-positive T cells in children with chronic active hepatitis B

The effect of short-term immunosuppressive treatment on the percentage of circulating DR-bearing T cells was investigated in 16 children with HBsAg-positive chronic active hepatitis. DR-positive T cells, thought to represent activated T cells, were significantly increased in all patients as compared to 10 age-matched controls [14.5 ± 4.2% (mean ± SD) vs. 0.4 ± 0.1%, p < 0.001]. Fifty-six percent of patients showed a decrease in the percentage of DR-positive T cells after 72 h of prednisone therapy. A response did not correlate with the presence of HBeAg, anti-HBeAg, or anti-delta antibodies. There was an inverse relationship (r = −0.56; p < 0.05) between the decrease of the percent of DR-positive T cells during immunosuppression and pretreatment alanine aminotransferase levels. The persistence of high levels of circulating DR-bearing T cells during therapy may represent the immunological counterpart of more severe disease, and of nonresponsiveness to corticosteroids.

Immunoregulatory functional abnormalities in children affected by HBsAg-positive chronic active hepatitis: role of prostaglandins in T-mediated suppression.

Suppressor cell function was evaluated in children affected by HBsAg-positive chronic active hepatitis. Circulating concanavalin A- (ConA) precultured lymphocytes failed to suppress the proliferative response of autologous responder cells to a mitogen. In four of eight patients with a failure of ConA-induced suppressor activity, indomethacin added during the induction phase of T suppressor cells abolished the defect, indicating that prostaglandin-producing adherent cells may influence ConA-induced suppressor activity. An inverse relation ship between suppressor cell activity and the number of suppressor/cytotoxic subsets defined by the OK T8 monoclonal antibody was found. Our findings strongly support the hypothesis that an abnormality in the immunoregulatory system plays a role in the pathogenesis of HBsAg-related chronic active hepatitis. It is also suggested that non-T regulatory cells are implicated in the immunological abnormality in chronic active hepatitis.

CORRELATION OF SERUM HYALURONIC ACID (HA) AND lAMININ (LAM) WITH STANDARD LIVER HISTOLOGYAND HISTOMORPHOMETRY-PROVEN LIVER FIBROSIS IN CHILDREN AFFECTED BY CHRONIC HEPATITIS B VIRUS (HBV) INFECTION

Non invasive assessment of the progression of liver disease in chronic HBV infection is crucial in cihldhood, where long follow-ups are expected. Value of several markers of liver fibrosis, cirrhosis and portal hypertension in children with chronic HBV infection however is at present either questioned (i.e. N-terminal propeptide of type III procollagen) or poorly known (i.e.HA, LAM). WE therefore studied by RIA method the serum levels of HA(1) and Laminin Pepsin REsistent Fragment PI (LAM P1) (2) in relation to: A) standard hystologic grading of liver disease severity (Student t), B) degree of portal tract fibrosis (um2) assessed by computerized histomorphometry using a Zeiss Kontron Videoplan analysis system (Pearson correl.) in 53 children with chronic B hepatitis (age 7.7± 3.9 y; range 2-13 y), 13 HBV carriers and 18 age and sex matched healthy controls.Results:Conclusions: HA serum levels may prove a useful quantitative marker for evaluating histologic liver CIR and fibrosis in children with chronic HBV infection. Serum levels of laminin, a constituent of basement membranes in the perisinusoida 1 space, probably reflect several degrees of portal hypertension, rather than liver CIR itself. Correlations between LAM PI serum levels and hepatic sinusoids capillarization are presently under study in our patients.1) Hepatoogy, 1985,5:638-42. 1)J Clin Chem Clin Biochem, 1985, 23:572-3

Isolation and characterization of two particle-bound oligoaminopeptidases from human meconium that are different from oligoaminopeptidase of adult small intestine.

Two oligoaminopeptidases (substrate L-leucyl-β-naphthylamide) have been separated by ion exchange chromatography after Triton solubilization of meconial particles. The quantitatively major form (oligoaminopeptidase II) has been purified to apparent homogeneity. The two meconial oligoaminopeptidases differ from each other in their polyacrylamide gel electrophoretic mobility and iso-electric points. Both meconial enzymes differ from the adult enzyme by having more acidic isoelectric points and different affinities to Helix pomatia lectin-Sepharose columns. Oligoaminopeptidase II has a faster anodal electrophoretic mobility than the adult enzyme but a similar apparent molecular weight and subunit structure. Extensive neuramini-dase digestion of meconial oligoaminopeptidase II does not modify the gel electrophoretic mobility of the enzyme. The charge difference between adult and meconial human brush border oligoaminopeptidases is therefore probably due, at least in part, to differences in the carbohydrate composition of these glycoproteins, and differences in the number of terminal or exposed sialic acid residues do not explain the observed charge differences.