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Studies were carried out on some biological activities of Helicobacter pylori porins in vitro. We extracted and purified a porin with an apparent molecular mass of 30 kDa. Human polymorphonuclear leukocytes preincubated with H. pylori porins showed a decrease of chemotaxis, of adherence to nylon wool, and of chemiluminescence. Used as chemotaxins in place of zymosan-activated serum or as chemotaxinogens in place of zymosan, the porins induced polymorphonuclear leukocyte migration. Human monocytes and lymphocytes cultivated in the presence of H. pylori porins released cytokines. Release of the various cytokines studied was obtained with differentiated kinetics and at various porin concentrations. Starting only 3 h after culture, tumor necrosis factor alpha is released quickly, reaching a peak at 18 h, at a porin concentration of 1 microgram/ml/10(6) cells. Interleukin-6 (IL-6) appears later, with a peak at 10 micrograms/ml/10(6) cells, while IL-8 is released after 6 h of culture, with a peak at 24 h, at a porin concentration of 10 micrograms/ml/10(6) cells, while IL-8 is released after 6 h of culture, with a peak at 24 h, at a porin concentration of 10 micrograms/ml/10(6) cells. Lymphocytes stimulated by H. pylori porins release gamma interferon after 18 h of culture at higher concentrations of porins (20 micrograms/ml/10(6) cells). Granulocyte macrophage colony-stimulating factor is released from 6 to 48 h at a concentration of 1 microgram/ml/10(6) cells, while both IL-3 and IL-4 are released after 18 h of culture at different porin concentrations (0.1 and 1 microgram/ml/10(6) cells, respectively). Our results lead us to think that during H. pylori infection, surface components, porins in particular, are able to induce a series of chain reactions ranging from the inflammatory to the immunological responses.

The A.A. refer a recent experience about the isolation and identification of same species of storaged timber mites. They believe that these mites are responsible of dermatitis at the trunk and the arms of timber workers. Mites are the most elderly living species on the earth, they can live and grow in different environments, such as plants, flowers, animals, men, earth, lake and sea waters, organical rubles, houses, mattresses, old books etc. There are free-living, saprophitic, parasitic and predator mites. Generally, primary mites live either freely or as commensals feeding on conserved foodstuff and on what they find available. Secondary mites, i.e. parasites and predators, live off primary mites and insects infesting foodstuff. Direct damage to foodstuff are not to be considered important, whereas indirect damages are more serious, due to the contamination of bodies and stools of mites that are rich in nitrogen. Some secondary mites may attack foodstuff workers causing characteristic dermatitis: they can act either directly, by sting and bites, or indirectly, provoking on allergic hypersensitivity. In this study the A.A. used the floating method to isolate timber mites, and then, these have been photographed at the microscope to obtain an easier and more complete identification. The A.A. describe a heterogeneous fauna consisting of both adult and larval-status insects, some species of free-living mites (Oribatula Tibialis) and, in particular, of two species secondary mites, predator, belonging to the Prostigmata sub-order. The Cheyletus Eruditus (Cheylatidae family) is a whitish mite feeding mostly on insect larva and primary mites living in foodstuff. When no prey is available, the Cheyletus Eruditus eats individuals of its own species. The Pyemotes Herfsi (Pyemotidae family) is a little white mite feeding on insect larva. It lives in conserved foodstuff and may attack man causing characteristic dermatitis such as those described by the A.A. The A.A. conclude dealing with the possible preventive and therapeutic measures tend to keep phisic-chemicals parameters of foodstuff and others conserved products afar from the values suitable for the growth of parasites (water content min. 13%, environmental humidity min. 60-65%, appropriate temperature etc.). Therapeutic procedure are based either on physical media: infra-red rays, gamma-rays, electric fields for the transformation of temperature or using chemical mixtures containing methyl bromide, carbon tetrachloride and hydrogen sulphide. Among the therapeutic procedures, however, the biological pest control using chemical media associated with antagonist mites of the infesting species is to be preferred.

After a brief analysis of the present epidemiological situation both international and of our country, on the possibility of early diagnosis on clinical and laboratory bases, the A.A. dwell upon the most frequent dental pathologies in case of AIDS and upon the possibilities of singling patients suffering from the so-called "spy-lesions" of the oral cavity, which are characteristic in most cases. The A.A. conclude by reporting the methodologies (materials and methods) which are to be used, from time to time, in order to carry out a careful and correct anti-AIDS prophylaxis in dentistry, either of individuals and medical personnel or of instruments and work-environments.