Patient factors affecting culture of Helicobacter pylori isolated from gastric mucosal specimens.

PURPOSE: Culture is one of the methods used for detecting Helicobacter pylori in the stomach. However, since it is costly, labor-consuming, and in a number of infected subjects gives a false negative result, the procedure is not routinely used. The aim of the study was to analyze some of the factors that may affect the outcome of H. pylori culture from endoscopic gastric mucosal specimens. MATERIAL AND METHODS: The study was conducted in a group of 265 subjects. The culture of gastric mucosal specimens was verified by urease test and histological examination. If the culture result was not consistent with one or two verifying tests, an additional two tests were used, i.e. H. pylori antigens in stool samples and anti-H. pylori antibodies in blood serum. RESULTS: In patients infected with H. pylori (at least two positive diagnostic tests), the analysis of factors that may affect the culture outcome revealed that neither age, gender, smoking, history of eradication, endoscopic diagnosis, use of proton pump inhibitors, ultrasonography of the abdomen or chest radiology performed the day before or on the day of gastroscopy, nor preparation for colonoscopy using osmotic fluids 1-2 days prior to gastroscopy had an effect on the culture outcome. Only high activity of gastritis (neutrophil infiltration) and low bacterial load in gastric mucosal specimens as well as drinking alcohol and the use of histamine H2 receptor blockers reduced culture efficacy in infected subjects. CONCLUSIONS: High activity of gastritis, low bacterial load, drinking alcohol and the use of histamine H2 receptor blockers can be the cause of failed H. pylori culture from gastric mucosa in the infected subjects. These factors should be taken into consideration when qualifying patients for the test and interpreting the results.

Application of immunoassay for detection of Helicobacter pylori antigens in the dental plaque.

PURPOSE: The aim of this study was to determine the viability of the commercial test currently used for detection of H. pylori antigens in the stool for detection of H. pylori antigens in dental plaque. MATERIALS AND METHODS: A total of 164 dyspeptic patients entered the study; 95 H. pylori infected (positive result of at least 4 of 5 diagnostic tests: Campylobacter-like organisms test (CLO test), histology, culture, stool antigens, serology) and 69 noninfected (negative results of 4 diagnostic tests: CLO test, histology, culture, stool antigens). Dental plaque was collected from natural teeth of the patients and incubated in microaerophilic conditions for 72 hours before immunoassay. RESULTS: Experimental findings included that optimal dental plaque weight to perform the examination was over 2 mg and that preliminary incubation increased significantly the number of positive results (p<0.002). It was also found that H. pylori antigens in the dental plaque were positive in 81.2% of infected and only 17.7% of non-infected subjects (p<0.001), while the reproducibility of results was 95%. CONCLUSIONS: The immunoassay for detection of H. pylori antigens in the stool may be used, after minor adaptations (specifically pre-incubation in microaerophilic conditions) for H. pylori antigen detection in dental plaque.

Indoor air studies of fungi contamination of social welfare home in Czerewki in north-east part of Poland.

PURPOSE: The contamination of the indoor environment with yeast-like fungi and moulds in social welfare home in Czerewki was evaluated. MATERIAL AND METHODS: The concentration of airborne fungi (in front of the building and in the corridors, patient rooms, study rooms, recreation rooms, kitchens, bathrooms, toilets) was determined using SAS-Super 100 (Pbi International). The fungal concentration on walls was assessed using the Count-Tact applicator and the plate Count-Tact irradiated (BioMerieux). Swabs were taken from the skin of the interdigital spaces of feet and hands, nails and the oral cavity of the residents. The fungi from the swabs were cultured on Sabouraud medium. Fungi were identified using standard microbial procedures. RESULTS: Tests of air and walls revealed significant differences in mycological flora in depending on the place isolation (e.g. corridor, rooms, reading room, nurse, room, kitchen, dining room, bathroom) and season (summer, autumn, winter, spring). A significant increase in the fungi isolated from the air and walls in the social welfare home was found, depending on the season. CONCLUSION: An increase in the fungi isolated from residents was found in relation to the season.

Pyrrole analogues of chloramphenicol. I. Synthesis and antibacterial activity of DL-threo-1-(1-methyl-4-nitropyrrole-2-yl)-2-dichloroacetamidopropane-1,3-diol.

The seven-stage synthesis of a pyrrole analogue of chloramphenicol [IX] was described. The compound exhibits a significant antibacterial activity, over the 12-50% range of the chloramphenicol activity.

Pyrrole analogues of chloramphenicol. II. Synthesis and antibacterial activity of DL-threo-1-(1-methyl-5-nitro-pyrrole-2-yl)-2-dichloroacetamidopropane-1, 3-diol.

The seven-stage synthesis of a pyrrole analogue of chloramphenicol (VII) was described. The compound exhibits a significant antibacterial activity.

[The influence of antibiotics on phagocytic and bacteriocidal activity of rabbit peritoneal macrophages stimulated by filtrates of cultured t-lymphocytes]. / Wplyw antybiotyków na fagocytarna i bakteriobójcza aktywnosc króliczych makrofagów otrzewnowych stymulowanych przesaczem hodowli limfocytów T.

The aim of the study was to determine the influence of twelve antibacterial antibiotics (various concentrations) on the activation of rabbit peritoneal macrophages. Macrophages were stimulated by filtrates of culture of lymphocytes T obtained from OVA immunized rabbits. Phagocytic activity and intracellular killing against Listeria monocytogenes were tested by fluorescence method. Penicillin G (0.4-50 mg/l), erythromycin and lincomycin (2.5-40 mg/l) used at all concentrations, were not exerting significant effects on activation of peritoneal macrophages. Cephalosporins, aminoglycosides, and rifampicin at low concentrations (0.4-5.0 mg/l) had no influence on phagocytosis and intracellular killing, also. Cephalosporins at concentration 10 mg/l (cephradine and cefamandole) and 50 mg/l (cefotaxime) inhibited intracellular killing and phagocytic activity. The same results were observed with ampicillin and ticarcillin (50 mg/l). The highest suppression effect was demonstrated using rifampicin at concentration 10 mg/l or more. Gentamicin, streptomycin and amicacin at concentrations 40 mg/l or more significantly inhibited macrophage activation in response to filtrates lymphocytes of culture. These inhibitions were more marked with gentamicin (10 mg/l) than amicacin (20 mg/l) or streptomycin (40 mg/l). All antibiotics did not stimulated the activity of peritoneal macrophages. The suppression activity of peritoneal macrophages by some antibiotics probably acts at the level of specific immune system by interfering with cytokine production.

[The effect of selected antibacterial antibiotics on production of interferon gamma (IFN-G) by mouse T lymphocytes stimulated by Listeria monocytogenes]. / Wplyw wybranych antybiotyków przeciwbakteryjnych na wytwarzanie interferonu gamma (IFN-G) przez mysie limfocyty T stymulowane paleczkami Listeria monocytogenes.

The aim of the study was to determine the influence of certain antibiotics on the production of IFN-gamma by mouse lymphocytes T after four days incubation with Listeria monocytogenes. The level of mouse IFN-gamma was determined by ELISA method (Inter Test-gamma Mouse IFN-gamma Kit, Genzyme). The strongest immunosuppression effect was demonstrated using rifampicin (39 ng/ml IFN-gamma) (Control: 123 +/- 29 ng/ml IFN-gamma, p < 0.05). Lower immunosuppression effects were observed also with cephradine (54 ng/ml IFN-gamma), amikacin (56 ng/ml IFN-gamma) and ticarcillin (83 ng/ml). The obtained results show that all tested cephalosporins (cephamandole, cefotaxime, cephradine) and aminogllycosides (gentamicin, streptomycin, amicacin) inhibit production of IFN-gamma by mouse lymphocytes T. The influence of penicillin G and ampicillin, as well as, erythromycin and lincomycin on the production IFN-gamma was not observed. Our results suggest that rifampicin, ticarcillin, cephalosporins and aminoglycosides act as inhibitors of production IFN-gamma.

[Effect of selected bacteria on mycelial transformation of cells of Candida albicans]. / Wplyw wybranych bakterii na mycelialna przemiane komórek Candida albicans.

Influence of selected bacteria representing typical physiological flora of mucous membranes of man on transformation of Candida albicans from yeast phase to mycelial phase was evaluated, E. coli, S. viridans and S. faecalis inhibited to different degree mycelial transformation of fungal cells. A degree of inhibition in the case of E. coli was proportional to the period of preliminary culture of strains in medium containing serum while streptococci inhibited mycelial transformation mainly after 4 and 24 hr of preliminary culture. Production of factor(s) inhibiting mycelial transformation of C. albicans by E. coli was induced by direct contact with fungal cells and by low molecular weight substances produced by C. albicans. Streptococci produced inhibiting factors even when fungal cells or their metabolites were absent in the medium.

[Isolation and identification of the products of Streptococcus faecalis inhibiting mycelial transformation of Candida albicans]. / Próba izolacji identyfikacji produktów Streptococcus faecalis hamujacych mycelialna transformacje Candida albicans.

An attempt was made to isolate and identify Streptococcus faecalis products responsible for the inhibition of mycelial transformation of Candida albicans. Five of streptococcal strains which 48 h broth culture supernatants run at 37 degrees C inhibited the most transformation of Candida albicans from yeast phase to mycelial phage. The strains were cultivated for 48 h in Tryptic Soy Broth at 37 degrees C, centrifuged and culture supernatants sterilised by means of filtration on millipore membranes of 0.4 micron diameter. After multistep purification of supernatants filtration on Diaflo PM 10 ultrafiltration membranes, Sephadex G 25, polyacrylamide gel electrophoresis) a homogenous, active fraction was obtained containing peptides of molecular weight around 6,000 Da. The peptides lost ability to induce mycelial transformation of C. albicans after heating at 100 degrees C for 10 min. Significant inhibition of morphological transformation of fungal cells was seen at the preparation concentration of 0.12 microgram/ml.

[Isolation of macrophage-activating phospholipid from Listeria monocytogenes]. / Izolacja fosfolipidu Listeria monocytogenes aktywujacego makrofagi.

The aim of this study was isolate a factor, contained in phospholipid fraction of Listeria monocytogenes, responsible for macrophage activation. Lipids extracted from L. monocytogenes cells were subjected consecutively to fractionation on colons with silicic acid, Florisil and Sephadex LH-20. Separated fractions were assayed for their ability to activate macrophages as well as for their homogeneity by thin layer chromatography. Multistep fractionation procedure allowed to obtain the pure preparation of glycerophospholipid with a high ability for macrophage activation and capable to increase significantly anti-infections immunity in mice.

The influence of some cephalosporins on immunological response.

The effect of cefotaxime and cephradine on the activity of some immune mechanisms was investigated in mice. It was found that cefotaxime in therapeutic doses did not affect the humoral and cellular immune response against sheep erythrocytes, whereas cephradine suppressed the humoral response in doses corresponding to those used for the treatment of patients. The response in vitro of mouse spleen lymphocytes to PHA was suppressed by both cephalosporins; however this occurred at therapeutic concentrations only in the case of cephradine. Neither cephalosporin affected the phagocytic and chemotactic activity of mouse peritoneal macrophages and rabbit microphages.

Sensitivity testing of bacteria to ceftriaxone using discs with different amounts of antibiotic.

Studies were performed to compare the results of sensitivity testing of bacteria to ceftriaxone using discs containing 10, 20, 30 and 40 micrograms of the antibiotic. The highest correlation between diameters of zone inhibition and MIC values was found with discs containing 30 micrograms of ceftriaxone. The lowest percentage of false results was also obtained with 30 micrograms discs.

The effect of phospholipids from Listeria monocytogenes and Aspergillus fumigatus on degradation of bacterial antigens by mouse peritoneal macrophages.

Investigations were carried out on an influence of phospholipids from L. monocytogenes and A. fumigatus on the degradation of Streptococcus faecalis cell walls by mouse peritoneal macrophages. It has been found, that macrophages from mice stimulated with phospholipids under studies degraded streptococcal cell walls labeled with DL-alanine-I-14C more efficiently than normal macrophages. Activated macrophages degraded also more rapidly antigenic structures of bacterial cell walls reacting with specific fluorescein-labeled antibodies. Moreover, the increase in activity of lysosomal acid hydrolases in stimulated macrophages was observed. The experiments performed suggest that increased ability of macrophages to degradation of bacterial antigens may be connected with a primary augmentation of lysosomal enzyme activity.

Influence of phospholipids from Listeria monocytogenes and Aspergillus fumigatus on the bactericidal and fungicidal activity of mouse peritoneal macrophages.

Investigations were carried out on an influence of phospholipids from A. fumigatus and L. monocytogenes on the bactericidal and fungicidal activity of mouse peritoneal macrophages. L. monocytogenes bacilli and C. neoformans fungi served as the experimental microorganisms. Phospholipids from A. fumigatus and L. monocytogenes were shown to significantly increase macrophage activity under in vivo and in vitro conditions. This was accompanied by an intensified bactericidal and fungicidal activity of extracts from the lysosomal fraction of phagocyte examined. Phospholipid-stimulated macrophages were observed to liberate bactericidal factors into the culture fluid. Lymphocytes had no influence upon this process.

Functional studies on mouse macrophages activated by phospholipids from Listeria monocytogenes and Aspergillus fumigatus.

The administration of phospholipids from Listeria monocytogenes and Aspergillus fumigatus to mice resulted in the development of macrophages with increased functional activity. It has been found that stimulated macrophages have increased phagocytic activity, enhanced chemotactic reactivity and augmented adherence to plastic surface. The activity of FcIg macrophages and complement receptors as well as the rate of the recovery of the FcIg receptors after phagocytosis were significantly higher in activated cells. The increase in phagocytosis, and FcIg and complement receptors activity was observed in macrophages cultured in vitro with phospholipids studied.