Acta microbiologica Hungarica最新文献

Delicate branching filaments, and cocci or rods, were seen by microscopic examination in the pus of the canaliculus lacrimalis in patients with chronic canaliculitis. Propionibacterium propionicus and different bacteria were cultivated and identified in the pus. After i.p. inoculation of mice with the Propionibacterium strains, the morphological changes characteristic of this microorganism were observed in the peritoneum, in the spleen and in the lung, giving an adequate explanation of the direct microscopic findings in the pus.

The effect of intravesical BCG vaccine treatment in 38 patients with superficial bladder tumour after TUR (Transurethral Resection) was followed by the lymphocyte transformation test (LTT) and the staphylococcus phagocytosis test of in vitro washed leukocytes. The results have confirmed the immunostimulating and hence anti-tumour effect of intravesical BCG vaccine. Monitoring of the cellular immune response is suitable for the continuous follow-up of the BCG effect. Comparing the tolerable side-effects with their favourable therapeutic results, BCG vaccine is considered to be effective for the prevention of recurrences in treating superficial bladder tumours.

The cytotoxic effects of the parent and radio-detoxified lipopolysaccharides (LPS and RD-LPS, respectively) were studied at various concentrations (0-50 micrograms/ml) upon cultured human lung carcinoma target cells. There was no significant difference between the effects of the two endotoxins. LPS and RD-LPS at the same concentrations, however, modified the cytolytic activity of human leukocytes (effector cells) and their mediators in different extent. The most remarkable difference was found at 10 micrograms/ml. A much higher cytotoxic activity of effector cells was observed in the case of RD-LPS as compared to the parent LPS. This concentration used for the treatment of X-irradiated and unexposed effector cells at 24 h incubation resulted in elevated release of some cytokines as measured by ELISA. For increasing the natural defence, RD-LPS as immunomodulator may be of practical value.

The effect of cadmium ion on growth and differentiation of the filamentous fungus Trichoderma viride was studied. Cd++ at a concentration of 10 mM strongly retarded growth and caused morphological changes. From cultures treated with cadmium, two white mutants and one yellow mutant were isolated. The white mutants formed no conidiophores and one of them produced colourless crystals in the cultivation medium. The yellow mutant differed from the parental strain mainly by the production of differently coloured conidia and by a slower growth rate.

Isozymes from 18 isolates representing seven species of the Fusarium sections Arthrosporiella and Sporotrichiella were compared by isoelectric focusing in polyacrylamide gels. Of the six enzyme systems tested esterase and malate dehydrogenase showed the largest variation. A numerical analysis of the pI values determined for acid phosphatase, esterase, glucose-6-phosphate dehydrogenase, malate dehydrogenase, phosphoglucose isomerase and phosphoglucomutase resulted in a dendrogam demonstrating the taxonomical relationships of the seven species. Fusarium avenaceum and Fusarium pallidoroseum were the two most closely related species. The high degree of isoenzyme dissimilarity among Fusarium chlamydosporum, Fusarium poae, Fusarium tricinctum, the fungi that produce pyriform or citriform microconidia, suggests that they are distinct species and their reduction to a variety level is not reasonable. The taxonomical distinctness of Fusarium camptoceras, a lesser known and rarely occurring fungus was also proven.

Experimental results suggest that protein kinase C (PK-C) may play a substantial role in the action of IFNs, but the precise biochemical pathway remains unknown. Recent evidences reveal the complexity of the mechanism of IFN-action and show that the IFN-alpha, -beta and -gamma induced pathways are overlapping. We briefly discuss what is known in this field and suggest a way in which the contrasting views might be reconciled.

Conidia of certain penicillin producing Penicillium chrysogenum industrial strains produced polyfructose. Two types of polyfructoses were formed by conidia of P. chrysogenum B10 from sucrose and with less yield from raffinose. Ten percent of fructans were in water insoluble form attached to the outer wall of conidia. The other, ethanol precipitable fructan formed a colloid opalescent solution. The latter had inulin type beta (2-->1) bonds--identified by 13C NMR spectroscopy--between fructose molecules and had a molecular weight of 217,000 Daltons. The KM value of sucrose hydrolysis--the first step of inulin production--was 0.86 M. The invertase hydrolysed about 70% of sucrose on the second day. Optimal conditions for inulin formation were: pH 6.0, 25-45 degrees C, 100 mg/ml sucrose, 10(7) spore/ml. The maximum conversion rate of fructose from sucrose into precipitable inulin was about 10% after 48 h incubation. The inulin production could be inhibited by glucose.

Starvation for 2 h does not disturb the insulin binding of Tetrahymena. At the same time imprinting does not develop at the first encounter with insulin and a down regulation is observed after 168 h. Starvation for 2 h reduces the insulin binding of the nucleus to the half value after starvation for 24 h and this change in binding becomes settled by 48 h. Imprinting is not elicited either in the nuclear membrane. The down-regulation can be observed also after 48 h but it is not present in the 168-h measurements. The experiments emphasize the increased sensitivity of binding sites of the nuclear envelope and the role of it in the development of imprinting.

The plasma fibronectin (pFN) concentration (cc) of untreated genetically or artificially athymic mice, or treated with TP-4 (thymus hormone sequence analog synthetic preparation) showed no significant difference from their euthymic or untreated controls. In contrast, the pFN cc in mice with different microbiological state showed significant alterations; the highest level occurred in conventional mice and the lower level in germfree mice was increased by bacterial monocontamination. The alternation from SPF into conventional state in nude mice also resulted in the increase of the pFN cc. Based on these and earlier results, it was assumed that the pFN cc is independent from the presence or absence of the thymus, but it depends on the actual microbiological state of the macroorganism.

Carriage of antigens and infectious herpes simplex virus type 1 (HSV-1) and human adenovirus type 1 (Ad-1) by salivary leukocytes was compared with the antibacterial activity of oral polymorphonuclear leukocytes (PMNL) and with the spectrum of oral bacterial and fungal flora. Risk of iatrogenic infections by microbes was assessed by detecting these viruses and microbes after disinfecting dental instruments. The results indicate carriage of antigens and infectious viruses in each age group between 6 and 60 years. Phagocytic activity by PMNL of virus carrier persons was found to be decreased as compared to virus-free subjects. The species number and survival after disinfection of oral bacteria and fungi were significantly higher in virus carrier persons. Infectious viruses were also obtained after disinfecting instruments used in their dental treatment. It is concluded that, virus infection of immune cells can contribute to the oral suppression of phagocytosis by PMNL. Intracellular viruses hidden from disinfectants can also result in infection of other subjects, especially if contemporary immunosuppression exists.