Microbiologica最新文献

Immunoblotting (IB) was used to detect the presence of serum antibody against each individual CMV structural polypeptide and the major nonstructural antigen during CMV hepatitis in 12 orthotopic liver transplant recipients to evaluate the diagnostic utility of this technique. The basic phosphoprotein p150 primarily, and to a much lesser extent p65 (lower matrix protein) and p52 (nonstructural DNA-binding protein) were the most recognized antigens by both IgG and IgM class antibodies. Collectively, IgM antibodies were detected to p150 in 9 of 12 (75%) patients and were detected before (2 cases), at the same time (1 case), or after (6 cases) detection of virus in cell cultures. IB was equal to indirect immunofluorescence (IIF) and enzyme immune assay (EIA) for the detection of IgG and superior to EIA for IgM class antibodies to CMV in OLT patients. Our results indicate that the p150 phosphoroprotein is an essential component of serologic assays, especially for the detection of IgM antibodies to CMV.

Three groups of crossbred calves were vaccinated with FMD vaccine only, combined FMD + rabies vaccine and rabies vaccine alone. Efficacy of the vaccines was determined by serum antibody assay at different intervals postvaccination. The results of the study indicated that the immune response of animals to a single inoculation of FMD vaccine only as well as combined FMD + rabies vaccine was unsatisfactory due to maternally derived antibodies to FMD virus antigen. However two inoculations elicited a satisfactory antibody response to FMD virus antigens in both group of animals. Rabies antigen alone as well as combined FMD + rabies antigen induced satisfactory serum antibody titres to rabies antigen. There was no significantly different serological responses in animal administered FMD vaccine only, rabies vaccine only or combined FMD + rabies vaccine.

A case of allergic bronchopulmonary aspergillosis without asthmatic attacks is described. An endobronchial biopsy established the diagnosis, and also highlighted histological aspects suggestive of a mechanism of humoral immunity for the pathogenesis of the disease process.

Twenty-nine strains of Bifidobacterium animalis, a species found only in animal habitats, were studied. Strains from known origins such as rat, rabbit and chicken feces and strains isolated from extrabody environments such as sewage and fermented milk products were examined. The intestinal origins of strains isolated from sewage and fermented milk products were determined by means of the comparison of electrophoretograms of cellular soluble proteins. Unknown origins of strains were recognized as being rabbit or chicken intestinal tract.

We have evaluated a simple and sensitive culture technique for isolation of Human Immunodeficiency Virus Type-1 (HIV-1) from small amounts of whole blood. Data shown in the paper demonstrate that: 1) cell cultures from small amounts of heparinized whole blood (HWB) allow a high isolation rate in infected subjects at all stages of diseases; 2) among asymptomatic subjects the HIV-1 isolation rate is increased in cell cultures from HWB, with respect to cell cultures from peripheral blood mononuclear cells; 3) cultural results from HWB are not influenced by the presence of detectable serum p24 antigen, but a good correlation was found with the titre of anti p24 antibodies in serum; 4) continuous cell lines (such as Molt-3 cells) instead of peripheral blood mononuclear cells can be used, obtaining good results, for HIV-1 isolation from HWB; 5) frozen samples of HWB can be used in cell cultures for HIV-1 isolation; 6) the type of anticoagulant (Heparin or EDTA) used for the collection of blood does not influence viral replication in cell cultures from whole blood; 7) viral isolation from HWB is highly sensitive; amounts so small as five microliters of whole blood are sufficient, in some cases, to obtain viral replication in cell cultures; 8) the minimal dose of HWB sufficient to infect cell cultures (HWB M.D.I.) varied among different patients. Although this work failed to establish a correlation between this parameter and the clinical and immunological status of patients, it is conceivable that HWB M.D.I. could give information about viral load in blood and have a prognostic significance; 9) the HWB M.D.I. rise in patients treated with Zidovudine, suggesting that this method could be employed in the virological evaluation of trials with antiretroviral drugs.

The epidemiological, clinical and therapeutical findings are described in a case of recurrent pulmonary histoplasmosis due to Histoplasma capsulatum. The patient, a bulldozer-operator, worked in Africa for a long period in extremely dusty conditions without any protection. Three different episodes of H. capsulatum pneumonia recurred during eighteen months after his return from Africa. A full dose treatment by Amphotericin B failed to eliminate disease recurrence on three occasions. The high concentration of airborne H. capsulatum spores inhaled could have been the main cause of the difficulty obtaining a rapid sterilization of the microorganism by Amphotericin B and disease recurrence. The late start of the treatment or the unexplained ability of some persons to develop repeated infections even with normal immunological parameters could be another explanation for the reported phenomenon.

Italian reports of PPNG strains are rare. In this paper we report the plasmidial characteristics of two strains: one harbouring 3.2 and 2.6 Mdal plasmids and the other 24.5, 4.5 and 2.6 Mdal plasmids. Restriction analysis was carried out on plasmids transferred to E. coli by transformation for "Africa" and conjugation for "Asia" plasmid.

The role of electrostatic interactions in the attachment and fusion at acidic pH of Sindbis virus (SNV) with goose erythrocytes was studied, investigating the effect of several anionic and cationic polyelectrolytes on SNV hemagglutination and hemolysis. In order to establish the target of active drugs, the compounds were incubated either with the virus particles or with the erythrocytes. Dextran sulfate was the only compound able to inhibit the attachment of SNV to the erythrocytes. Fusion of virus with red cells was reduced dose-dependently by the polyanions dextran sulfate, mucin and polygalacturonic acid. On the contrary two polycations, polylysine and polybrene, enhanced viral hemolytic activity. However the effect of polyions is not exclusively related to the electric charge since ineffective molecules were found in both classes of compounds.

We investigated a group of well characterized seronegative subjects "at risk" for HIV-1 infection including heterosexual partners of HIV-1 infected subjects and intravenous drug abusers. Pokeweed mitogen (PWM)-stimulated peripheral blood mononuclear cells (PBMCs) were studied for their ability to produce antibodies against HIV-1 structural proteins in vitro. Viral activity by means of HIV-1 isolation from PBMCs and presence of serum p24 antigen were also tested. In 7/42 cases (16.6%) HIV-1 immunoreactive specific antibodies were found, mostly directed against the envelope proteins (gp 120/160). Remarkably, none of these in vitro antibody producers yielded HIV-1 isolation in cell cultures or had detectable serum levels of p24 antigen.

4.2% Pseudomonas aeruginosa strains isolated in our hospital were resistant to ceftazidime. The 174K strain was also resistant to azthreonam but susceptible to imipenem and was studied as representative of these strains. It produced a single beta-lactamase (pI 8.6) which had all the characteristics of the chromosomal beta-lactamase Id and was the only beta-lactamase present. This enzyme hydrolyses slowly ceftazidime and imipenem. It could be a factor of imipenem resistance if the antibiotic influx into the bacteria was decreased or if the beta-lactamase Id was synthesized at a high level.