Giornale di batteriologia, virologia ed immunologia最新文献

After analysing the etiopathogenesis and transmission process of the microorganism, the Authors have examined the latest and documented outbreaks owing to food-borne strains of Listeria monocytogenes in Europe and in North America. The considered studies indicate an increase of listeriosis cases caused by infected food, especially food of animal origin, such as meat and milk-dairy products.

Serum anti-HBc IgA antibodies can be demonstrated in acute hepatitis B patients. At first, they are mainly polymeric (p-IgA), whereas monomeric IgA (m-IgA) become detectable 3 months later. In most cases, anti-HBc IgA cannot be demonstrated after 6-12 months. From a diagnostic point of view, specific p-IgA can be regarded as a marker of active infection but, compared to IgM, their demonstration is more difficult.

In the last fifteen years the role of cytokines in the modulation of anti-tumor responses has been extensively studied at the Institute of Microbiology of the University of Turin. In retrospect many observations appear to have been quite innovative and original. Altogether they form the steps of a consequential intellectual endeavour leading progressively towards a precise definition of the role of the lymphokines in modulating the immune response to neoplasia. Starting from the characterization of the tumor signals required for lymphokine induction, this research progressed towards the definition of the cellular, molecular and genetic mechanisms involved, and provisionally ends with the direct manipulation of lymphokine genes transfected to tumor cells.

A retrospective study was made of all blood cultures performed over a 40-month period at the Ivrea-Castellamonte Hospital (Turin, Italy). A total of 4386 vials from 619 patients were examined. There were 619 positive vials (14.1%) from 131 patients (21.2%) corresponding to 145 bacteremia episodes, including 129 monomicrobial (89%) and 16 polymicrobial (11%). Ten patients (1.6%) had more than one episode. There were 73 polluted vials (1.7%). A total of 165 microorganism were isolated: Gram-positive (52.7%) and Gram-negative (46%) bacteria, and mycetes (1.2%), anaerobic flora (9.7%). The predominant families were: Enterobacteriaceae (29.5%), Micrococcaceae (27.3%), Pseudomonadaceae (4.8%), Bacteroidaceae (4.8%) and Streptococcus "Genus" (18.8%). The species frequencies were: Escherichia coli (20%), Staphylococcus aureus (15.8%), Enterococcus (8.5%), Staphylococcus epidermidis (7.3%), Pseudomonas aeruginosa (4.8%), Proteus mirabilis (4.2%), Brucella spp. (2.4%), Bacteroides fragilis, Streptococcus bovis e Propionibacterium acnes (1.8%). These findings are compared with those published in the Italian and international literature. Stress is laid on periodical review of the isolations from samples of this kind as a useful aid towards the diagnosis and treatment of hospital infections, and in their monitoring and epidemiological evaluation.

The AA. studied the effects of a polyvalent oral vaccine on the cellular immunity, and on IgA level in animal. They also studied its ability to reactivate the response to the Clostridium tetani toxin in human volunteers. The results show a very good ability of the vaccine as specific and aspecific stimulator.

An antagonistic activity of Enterococcus faecium SF 68 towards Plesiomonas shigelloides, Aeromonas sp., enteropathogenic Escherichia coli and Yersinia enterocolitica has been studied and demonstrated.

Host-parasite interactions were studied by several researchers in these last years, both to better understand some parasite diseases and to identify new targets and strategies for the control of these infections. In this paper some of the most important recognition's mechanisms demonstrated between specific parasite structures and host cell receptors are reported, and particularly those concerning protozoa Leishmania, Plasmodium, Entamoeba, Giardia and Pneumocystis.

The Authors have tested the new Tb-Elisa method to detect specific antibodies, raised against A60 major mycobacterial antigen complex, in patients of groups II, III and IV of CDC classification suffering from acquired immunodeficiency and in HIV-1 negative control subjects. The test results support laboratory diagnosis of acute phase and reactivation of mycobacterial infection.

Enteric infections in childhood are estimated to be a primary cause of illness and death in the third world and Rotaviruses play a very important role in acute nonbacterial diarrheal enterocolitis. The Authors analyse the latest results of the direct investigation of the virus in the feces by ELISA method. The improvements in diagnostic techniques and the new knowledges about Rotaviruses and their pathogenic power acquired during the last decade have made it easier to know the consequences of Rotavirus infections particularly in the poorest countries, with very bad sanitary conditions. Much attention has therefore been paid to the study of dietetics and immunoprophylaxis in order to find the most suitable cure. At present only some vaccines of animal origin are available that many Authors consider to be harmless, and that, might hopefully be employed in the third world countries.

IFNs are a family of proteins produced by various cells following stimulation by biological or synthetic inducers. The interaction with the membrane receptor is followed by the activation of the expression of particular genes that are responsible for their antiviral, antiproliferative and immunomodulatory properties. Initiation of transcription is an early and critical event in the control of eukaryotic gene expression. In this review we will briefly discuss the mechanisms exploited by IFNs to control at transcriptional level the expression of inducible genes. In particular we will focus on some characteristics if cis-acting DNA elements that are located upstream from the initiation site for RNA transcription and of nuclear trans-acting factors that are required for modulation of gene expression by IFNs.