Giornale di batteriologia, virologia ed immunologia最新文献

An important role in the interaction between protozoan parasite Leishmania and host is determined by serum factors. The activation of complement can have resistance-promoting effects (due to the lysis of parasite) or disease-promoting effect (due to the opsonization of Leishmania). Also lymphokines can determine resolution or progression of the infection. Particularly, gamma-interferon "in vitro" increases the killing of the parasite and "in vivo" cures cutaneous leishmaniasis.

A study was made of 92 bacteremia episodes among patients admitted to the Ivrea-Castellamonte Hospital (Turin, Italy) between June 1986 and September 1989. A single microorganism was isolated in 84 episodes (91.3%), the most common being: Staphylococcus aureus (21.7%), Escherichia coli (18.5%), Enterococcus (9.8%), Pseudomonas aeruginosa (6.5%), and Proteus mirabilis (5.4%). The episodes were of both hospital and community origin: 54.3% vs. 45.7%. Their main sources were: the urinary tract (16.3%), abdominal infections (14.2%), endocarditis (7.6%), and the respiratory tract (5.5%). No source could be identified in 26%. Brucellosis, salmonellosis and listeriosis together constituted 8.7% of the episodes. Abdominal infections were primarily responsible for the 8 cases (8.7%) of polymicrobial bacteremia. The overall mortality was 18.5% (6.5% community vs. 12% hospital episodes). Mortality directly due to bacteremia was 8.7%. Bacteremia was the direct or indirect cause of death in 22.6% of patients greater than or equal to 65, compared with 19% and 10% in those aged 35-64 and 15-44 respectively. The patient's clinical picture at the time of infection was a prognostic factor: mortality was much lower in subjects previously healthy or free from basic diseases (11.8%) than in those with non-rapidly-fatal diseases (21.7%) or rapidly-fatal diseases (54.5%). Bacteremia-linked mortality (direct and indirect) was higher in Gram-positive vs Gram-negative infections: 22.2% vs 15.8%. Mortality was 12.5% in the group of patients with polymicrobial infections.

The central role of Streptococcus mutans in the pathogenesis of caries is universally recognized. In this article we discuss bacterial metabolism relevant to plaque formation and enamel destruction, and review current methods and new prospects in caries prophylaxis: the use of fluorine, possible substitutes for sucrose, active and passive immunoprophylaxis, teeth colonization with non-cariogenic strains of S. mutans. No one of these methods can be considered a definitive solution for every caries problem, but short term major achievements can be reasonably attained by ongoing field research.

Cells of Candida albicans, after 24 hours of growth in YM, were starved, alternatively, in citrate buffer, physiological solution, MMS deprived of glucose or ammonium sulphate. The eventual growth was monitored by determining the absorbance at 675 nm. Simultaneously, the cell morphology was also controlled. In a second series of experiments, the C. albicans cells taken from YM were starved for 72 hours in one of the mediums as stated above, and then reinoculated in MMS liquid without, alternatively, glucose or ammonium sulphate. Again the eventual growth was monitored as in the above method. The achieved results indicate the presence of a reserve of nitrogen, which can be utilized when a source of C is given to the cell. We therefore discuss the apparent lack of glucidic reserve and we propose a method for the consumption of nitrogen reserve. The aim of the work is to define how to obtain cells that contain the smallest amount possible of endogenous reserve.

In our laboratory KES group bacteria account for about 11% of all strains isolated from in-patients and are responsible for serious infections. Their well known increasing tendency to become resistant to beta-lactams prompted us to the KES strains isolated in medical or surgical patients in 1986.87. 30 Klebsiella retrospectively review the susceptibility to antibiotics of strains out of 59 had been isolated in that period from patients previously treated with beta-lactams: no significant variation in resistance to cephalosporins, compared to the 29 strains from non treated patients, was noted. However in the treated group one strain of Klebsiella pneumoniae out of 24 showed resistance to ceftazidime and one of Klebsiella oxytoca was resistant both to cefotaxime (1 out of 16) and ceftriaxone (1 out of 12). 19 strains of Enterobacter spp. out of 32 had bees isolated from treated patients; a significant increase in resistance to 3rd generation cephalosporins (p less than 0.01), compared to the 13 strains isolated from non treated patients, was noted. Our findings suggest that it is advisable to review the in-use antibiotic policy keeping in mind the severity of the infections caused by KES group bacteria.

An indirect enzyme-linked immunosorbent assay, using antigen coupled to paper, has been adapted for the detection of Brucella melitensis antibodies. Optimum conditions were achieved by incubation of 1 ml of diluted serum with a single piece of paper coated with purified Brucella antigens for a period of one hour, and by addition of a goat anti-human enzyme conjugate antibody for one hour again. Under these conditions 80 human sera were examined and the results obtained were compared with Wright agglutination test.

The results of a study made in the areas of Central Italy on a random community on the significant presence of cases with seroantibodies against Campylobacter, Yersinia, Legionella Pneumophila, Francisella Tularensis and Rotavirus confirm the hypothesis on the presence in the territory of microorganisms responsible. These positivities in man are not only single but also contemporaneous for at least two microorganisms. Hence the hypothesis of the presence in the environment (animals, soil, surface waters) of the microorganisms (Campylobacter, Yersinia, Legionella Pneumophila, Francisella Tularensis, and Rotavirus) responsible for the zoonoses of interest for man.

Ciprofloxacin was given in oral doses of 250 mg. each 8 hours to 21 patients with otitis. The efficacy of treatment was assessed by clinical and bacteriological parameters. The 61.9% of isolated bacteria are opportunistic. A case of chronic otitis by Achromobacter xylosoxidans is described.