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Helicobacter pylori (H.p.), has been shown, experimentally, to exert a proteolytic activity against mucous fractions. Aim of this study was to assess the prevalence of H.p. in peptic ulcer and to analyze its possible influence on gastric mucus components, on peptic activity in gastric juice and the possible action on peptic secretion. 223 patients undergoing upper gastrointestinal endoscopy were analyzed for the presence of H.p. in the mucosa: 99 duodenal ulcer patients (D.U.), 58 gastric ulcer patients (D.U.) and 66 dyspeptic subjects. In each patients, three contiguous gastric biopsies were taken at the antrum: the first was evaluated for gastritis (Whitehead Criteria), the two other analyzed for H.p. with a rapid urease test. In a subgroup of 25 D.U. and 18 G.U. patients, two other biopsies were taken at the fundus corpus of the stomach, to evaluate peptic secretion. To determinate mucous components (acid and neutral glycoproteins, galactose and N-acetylneuraminic acid), gastric juice samples were collected during endoscopy. H.p. was present in 89% of antral biopsies in D.U., in 56% of G.U. and in 51% of D., and was associated to antral gastritis. As regard gastric juice components, we observed an increase and a decrease of acid glycoproteins, respectively, in D.U. and G.U. patients with H.p. infection. An increase of peptic activity has been found in the gastric juice of both gastric and duodenal ulcer patients H.p. positive (G.U. p less than 0.05). On the contrary, no significant differences were observed on peptic activity in the fundus-corpus biopsies between H.p. positive and H.p. negative patients.(ABSTRACT TRUNCATED AT 250 WORDS)

The Author, after recalling the fundamental concepts of the function and structure of living cells, illustrate the functions characteristic of cellular membranes. He examines in detail the principal models which have been proposed for the interpretation of the structure of membranes, particularly those of DANIELLI and DAVSON and of ROBERTSON. He recalls his own biochemical experiments on the endoplasmic reticulum of the liver and spleen, from which useful information can be drawn on the locating of some catalytic proteins in the membrane. He then devoted particular attention to the relationships between proteins, lipids and glucides as constitutent parts of membranes and discusses the recent "fluid mosaic model" proposed by SINGER and NICOLSON. He concludes giving some examples of the functional flexibility of membranes and remarks that the collaboration between biochemists and electron microscopists has proved in the last few years to be a fertile point of encounter, promising results which will provide spectacular information on the structure and function of cellular membranes.

In the present study we have analyzed the biochemical characteristics of murine immune interferon (IFN-y). Ionic or non-ionic detergents inactivate IFN-y, while as far as organic solvents are concerned only those with high polarity inhibit antiviral activity. Finally when different kinds of enzymes were used, proteases but not lipases or neuraminidase inactivated IFN-y.

Personal experience with acute enzymatic pancreatitis in 113 cases observed, over 11 years, at the Santa Croce Hospital Surgical Division is described. Only 58 cases (51,3%) were submitted to surgery and the remaining 55 cases (48,7%) were treated with medical therapy. A mortality of 16,8% was observed.

The aim of the present paper is to evidence whether a variation of activity of neutral proteases occurs during regeneration and neonatal growth in rat liver. Protease activity is assayed with a spectrophotometric method in total liver and hepatocyte homogenates using casein as substrate. Results show that the protease activity is Ca++-dependent; it is lower either in neonatal liver or in regenerating liver 4 hours after partial hepatectomy with respect to controls.

Laennec and later workers attributed the aetiopathogenesis of emphysema to mechanical causes. This view has been superseded by the current proteolytic theory. It is now believed that the destruction of the pulmonary parenchyma in emphysema occurs when the homeostatic equilibrium between cellular proteases (polymorphonucleates and macrophages) and serum antiproteases (primarily alpha-1-antitrypsin) which protects the respiratory ways, is disturbed. This imbalance not only produces idiopathic emphysema due to alpha-1-antitrypsin but also post-bronchitic forms due to increased protease release.

Within the framework of immunological mechanisms involved in allergic forms, and view of the fact that immunoglobulins represent one of the cardinal points thereof, the attention is focused on the IgA, first getting a deeper insight into the current knowledge of their structure and localization, which has recently been added to with some important details. The models set forth are aimed to show the molecular organization of monomeric and polymeric IgA, and the functional significance of their different distribution in secretory and serous tissues, with particular stress on the action displayed by IgA specific bacterial proteases. Thus the problem of IgA synthesis and secretion, analyzing the model of formation of secretory IgA, and the defensive role they play in protecting the mucous surfaces, is tackled. Lastly, within the framework of IgA-specific immunodeficiencies, the pathogenetic mechanisms of the selective hypo-IgA, the variability of the IgA selective defect, and the pathology connected therewith, are examined with particular stress on the relationships between IgA and allergopathies along with the latest immunotherapy trends, understood as a supply of the lacking immunoglobulin class.