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Summary: Prevalence and incidence ofHelicobacter pylori infection among 250 Italian military students were studied using specific IgG antibodies. Subjects susceptible at enrollment were evaluated during a 10-month follow-up period, when two serum samples were collected after 5 and 10 months, respectively. Samples were also analyzed for anti-CagA (a protein associated with virulentH. pylori strains) IgG antibodies. Finally, spectrotypic analysis by isoelectric focusing and reverse blotting, (IEFRB) was performed in the majority of positive samples. Forty-three out of 250 (17.2%) were positive at the time of enrollment, a seroprevalence rate very similar to that observed in a larger Italian military population 5 years earlier. Among the 207 susceptible subjects, two seroconverted at 5 months after enrollment; they were still positive at the end of follow-up (incidence rate of 1.16 per 100 person/years of exposure). This data suggests a spread ofH. pylori in the Italian military population that is not negligible. Nearly all anti-H. pylori-positive subjects were also CagA antibody positive (agreement percentage: 97.6%; K=0.91), suggesting that the large majority ofH. pylori strains were of the virulent type. Sixty-four percent of positive sera presented an oligoclonal spectrotype, which seems to be a hallmark of humoral immune response toH. pylori.

Summary In order to investigate the role played by zidovudine (ZDV) as immune modulator, particularly on B-cell response, the anti-V3 loop spectrotype in 115 sera from 26 HIV-infected individuals was evaluated, prior to and during treatment with ZDV, by isoelectric focusing and reverse blotting (IEF-RB), a technique useful for indirectly measuring the activity and the number of B-cell clones. All 18 patients showing seroreactivity by IEFRB displayed a clear oligoclonal banding pattern, with no change in the spectrotype (i.e. new bands), in sequential analysis over the course of therapy. Only minor changes in band intensity were found, without any correlation with ZDV treatment or CD4+ cell count. In addition, among the sera reactive in spectrotypic analysis, the percentage of those with p24 antigen positivity was significantly lower than those with no detectable p24 antigen (19.8% vs 80.2%, respectively, p=<0.0001, Fisher's exact test). In conclusion, it could not be demonstrated by IEFRB that there was any effect of ZDV on the activity and the number of anti-V3 specific B-cell clones. This data is in line with previous studies showing the constancy of anti-gp120 antibody spectrotype over the long course of the disease.

The mechanism for the pathological increase in cell death in various disease states e.g. HIV immunodefficiency or even ageing or Alzheimer's disease, occurs by complex and as yet undefined mechanism(s) related to immunological, virological or biochemical disturbances (i.e. energy depletion, oxidative stress, increased protein degradation). We have studied mitochondrial uncoupling or inhibitor toxicity on neurones at the cellular level and at the mitochondrial level using rhodamine (Rh123) and 10-nonylacridine orange (NAO) fluorescence with confocal microscopy. Blockade of the mitochondrial chain complexes at various points was studied. The possible protective effects of the compound l-carnitine, which plays a central role in mitochondrial function, was tested in this form of neurotoxicity. It appears that l-carnitine and its acetylated form, acetyl-l-carnitine, can attenuate the cell damage, as assessed by lactate dehydrogenase (LDH) release, evoked by the uncoupler, p-(trifluoromethoxy)phenylhdyrazone (FCCP), or by the inhibitors, 3-nitropropionic acid (3-NPA) or rotenone. Further, the FCCP-induced inhibition of Rh123 uptake was antagonized by the preincubation of cells with l-carnitine. Since such neurotoxic mechanisms may be operating in the various pathological forms of myotoxicity and neurotoxicity, these observations suggest potential for a therapeutic approach.

In Italy, a dramatic decline of hepatitis B infection occurred in recent years as a result of nonmedical and medical factors. The national type-specific surveillance system shows that the age of maximum incidence changed from early childhood, when the risk of becoming a chronic carrier after infection is very high, to late adolescence. Data of several seroepidemiologic studies are consistent with this picture, but could not be compared with previous data on similar age groups. In 1981, a seroepidemiologic study on a national sample of 5,005 recruits showed a high prevalence of serologic markers of hepatitis B infection among young adults in Italy. In 1990, the authors replicated that original study on a national sample of 4,993 recruits. The adjusted prevalence of hepatitis B core antibodies among Italian male recruits dropped from 16.8% to 5.8% in 9 years. The authors anticipate a substantial reduction in the rate of production of chronic carriers and the rates of liver cirrhosis and primary liver carcinoma in Italy in the next decades. Vaccination campaigns, especially if combined with nonimmunologic preventive measures, will further reduce the rate of hepatitis B infection in Italy.

In 1990, a prospective serological survey to estimate the rate of clinical and inapparent infection with hepatitis A virus (HAV) was performed in a cohort of 1,268 soldiers, 18–24 years old, during an 8 month period in the Campania region in Italy. At the time of enrollment 318 (25%) of the 1,268 soldiers were positive for total antibodies to HAV (anti-HAV). None of them was positive for IgM anti-HAV. Among the 950 susceptible subjects who were followed up for 8 months, eight (0.8%) later seroconverted to anti-HAV positivity. This figure corresponds to an incidence of 1.3/100 person/years (eight seroconversions during 633.3 years of observation). There were two clinical (with presence of IgM-anti-HAV) and six inapparent infections. The clinical/subclinical HAV ratio was 1 : 3. These findings indicate that the risk of HAV infection among soldiers residing in this area is not negligible.