A mathematical model predicting anti-hepatitis B virus surface antigen (HBs) decay after vaccination against hepatitis B.

The determination of serum levels of antibodies against hepatitis B virus surface antigen (anti-HBs) after hepatitis B vaccination is currently the only simple test available to predict the decay of protection and to plan the administration of booster doses. A total of 3085 vaccine recipients of plasma-derived and recombinant vaccine have been followed for 10 years to determine the kinetics of anti-HBs production and to construct a mathematical model which could efficiently predict the anti-HBs level decline. The anti-HBs peak level was reached 68 days after the last dose of recombinant vaccine and 138 days after the last dose of plasma-derived vaccines.

[Expression of the interleukin-2 receptor in T lymphocytes of the rheumatoid synovial membrane].

Indirect immunofluorescence was used to stain DR antigen and interleukin-2 receptor (Tac) of T-lymphocytes (Leu 4+). Tissue samples of synovial membrane were cut from arthroscopic biopsies of inflamed knees in four patients with active rheumatoid arthritis (RA). Consecutive cryostatic sections of rheumatoid sinovium were analysed using monoclonal antibodies.

Tissue antigen distribution in hepatocellular carcinoma.

An immunohistochemical study on 63 hepatocellular carcinomas (HCC) was performed for the demonstration of alpha 1-antitrypsin (AAT), alpha-fetoprotein (AFP) and hepatitis B virus (HBV) antigens. AAT and AFP were also investigated in 54 cases of cirrhosis not associated with HCC. AAT was frequently expressed both in HCC (82.

Membranous glomerulopathy and hepatitis B virus (HBV) infection in children.

Histological examination of renal biopsies in 64 Neapolitan children aged 13 months to 14 years who presented with nephrotic syndrome or persistent hematuria and/or proteinuria revealed membranous glomerulopathy (M.G.) in 14.

Correlation between Ito cells and fibrogenesis in an experimental model of hepatic fibrosis. A sequential stereological study.

The relationship between Ito cells and hepatic fibrogenesis has been investigated in an experimental model: intraperitoneal injection of heterologous serum in rats leads to the appearance of fibrous septa within 5 weeks. Groups of rats were sacrificed at various intervals (from 2.5 to 20 weeks), saline-injected rats being used as controls.

A post-embedding method: demonstration of fibronectin on human liver by PAP technique.

Fibronectin, one of the most relevant components of extracellular matrix, seems to mediate cell to cell and cell to substrate interactions by means of selective links with collagen fibrils and glycosaminoglycans. Post-embedding technique using PAP method has allowed us a precise localization of fibronectin on semi-thin sections and on adjacent thin sections, improving the knowledge of fibronectin-collagen relationships.

Relationship between connective tissue cells and fibronectin in a sequential model of experimental hepatic fibrosis.

The cellular and non-cellular components of fibrous septa formed at early and late stages in a sequential model of experimental hepatic fibrosis have been investigated using ultrastructural and immunocytochemical techniques. In the early septa, cells with intermediate features between lobular Ito cells and active fibroblasts were formed. These cells frequently displayed subplasmalemmal microfilaments (myofibroblast-like cells).

An improved method for HBcAg demonstration in paraffin-embedded liver tissue.

Factors influencing the preservation of HBcAg in formalin-fixed, paraffin-embedded liver tissue have been analysed. Fixation time, choice of the embedding medium, deparaffinization and selection of anti-HBc proved to be critical variables. For optimal results, fixation in 4% buffered formalin for no longer than 24-48 h, the use of wax with a low melting point, a heating step prior to deparaffinization, and a search for anti-HBc specifically reactive for paraffinated HBcAg are recommended.

Histochemistry of gamma-glutamyl transpeptidase in human liver biopsies.

The histochemical activity of gamma-glutamyl transpeptidase is examined in human liver biopsy specimens in normal and pathological conditions. Different histochemical patterns can be recognized. In histologically normal liver a faint sinusoidal membrane staining is observed.

HBsAg-induced hypertrophic smooth endoplasmic reticulum as a target for liver-kidney microsomal (LKM) antibodies.

To test the hypothesis that LKM antibodies are directed against antigen(s) of the smooth endoplasmic reticulum, liver biopsies from patients with HBsAg chronic hepatitis, rich in liver cells with HBsAg-induced hypertrophic SER, were used. A close correspondence was seen between cells with HBsAg-positive cytoplasm by immunoperoxidase and cells with a stronger and more homogeneous fluorescence by indirect immunofluorescence with LKM-positive sera. These results point to antigenic components of SER as reacting with LKM antibodies.

Ultrastructural changes in the liver of patients with chronic non-A, non-B hepatitis.

Electron microscopy examination of liver biopsies from 8 patients with chronic non-A, non-B hepatitis revealed ultrastructural changes similar to those previously described in chimpanzees with experimentally induced acute non-A, non-B hepatitis. These changes consisted of intranuclear clusters of electron-dense, 15-27-nm particles that were detected in five out of the eight patients and of circular cytoplasmic structures that were present in seven cases. Other cytoplasmic abnormalities found in our patients related to the presence of curved membranes apparently developing from apposition of two cisternae of endoplasmic reticulum.

Changes in the small biliary passages in the hepatic localization of Hodgkin's disease.

The authors have investigated the behaviour of the small biliary passages in the liver biopsies of six patients suffering from untreated Hodgkin's disease with hepatic localization. No obstruction of the major bile ducts was demonstrated in any patient. Three of the patients were anicteric, while the three others presented with jaundice.