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Biomedical subjects

W Roszkowski

Publications and source records attributed to W Roszkowski.

At least 37 records · Page 2Linked to original sources

Tetracycline and 13-cis-retinoic acid inhibit production and activity of granulocyte activating factor (GAF) from Propionibacterium acnes.

The aim of this study was to evaluate different treatment schedules on release or activity of a granulocyte activating factor (GAF) from Propionibacterium acnes. Incubation of P. acnes in physiological saline (30 min, 37 degrees C) resulted in release of a soluble factor that elicited considerable chemiluminescence response and chemotactic stimulus on human granulocytes. Pretreatment of the microorganisms with subinhibitory concentrations of tetracycline or incubation of granulocytes with 13-cis-retinoic acid significantly reduced the activating potency of GAF on these phagocytic cells. Since GAF was considered to be one of the stimuli for inflammation in acne vulgaris, administration of tetracycline and 13-cis-retinoic acid appears to be an adequate therapy.

Chemotaxis, Leukocyte↗

Immunomodulation by propionibacteria.

The ability of bacteria and bacterial products to modulate the immune response to unrelated antigens is well documented. Propionibacteria are amongst the most potent immunomodulators stimulating cell populations involved in nonspecific resistance. Generally, the activated immune system provides protection from infectious pathogens and malignancies via mechanisms of recognition and elimination. Accordingly, administration of propionibacteria could be shown to be of benefit in the treatment of neoplastic and infectious diseases. Thus, it can be recommended for further clinical investigations.

Adjuvants, Immunologic↗

Lectins: mediators of adhesion for bacteria in infectious diseases and for tumor cells in metastasis.

Adhesion of bacteria and adhesion of tumor cells have much in common, especially the participation of lectins in this process. In the future it might be possible to inhibit the metastatic process into the liver (e.g. during surgical operations of malignant tumors) and bacterial adherence to mucosal linings or plastic devices by blocking of adhesion molecules (lectins) with appropriate glycoconjugates. Initial clinical trials are very promising.

Animals↗

Biological properties of staphylococcal lipoteichoic acid and related macromolecules.

Lipoteichoic acids (LTAs) and related macromolecules (e.g. cell surface substance, CSS; cell surface antigen, CSA; cell surface complex, CSC) are a group of phosphate-containing polymers associated with the cell walls of Gram-positive bacteria (32). They may be considered as surface-reactive antigens (immunogens, biological response modyfiers) as well as membrane components which mediate the attachment of certain bacteria (S. saprophyticus, S. aureus, group A streptococci) to host cell tissues.

Animals↗

[Effect of cellulose on iron, zinc and copper metabolism in growing rats].

The purpose of the study was determination of the effect of cellulose on the apparent absorption and tissue concentrations of iron, zinc and copper in growing rats. Male Wistar rats with initial body weight 108 +/- 2 g were fed during 6 weeks isocaloric diets containing 1%, 5% or 10% of dietary fibre. The diets contained about 18% protein (casein and wheat gluten 1:1) and iron 28 mg, zinc 17 mg and copper 4.5 mg per kg of diet. In the 2nd, 4th and 6th weeks of the experiment feaces were collected during 2 days. Mineral components of the diets, cases liver, spleen, kidneys and femur were determined by atomic absorption spectrophotometry. No significant differences were noted in diet intake or in body weight gain between these groups. Increased cellulose content in diet, that is 5% or 10%, reduced significantly the absolute and per cent apparent absorption of copper and its concentration in liver, which indirectly led to disturbances of iron metabolism. As a result, the concentration of haemoglobin was reduced and the hepatic iron reserve was raised. No adverse effect of cellulose was found on the apparent absorption of iron and zinc and on zinc concentration in the studied tissues. The per cent coefficients of apparent absorption of iron decreased during the experiment, while those of zinc and copper increased.

Age Factors↗

Blocking of lectin-like adhesion molecules on pulmonary cells inhibits lung sarcoma L-1 colonization in BALB/c-mice.

Adhesion and inhibition experiments with pulmonary cells of BALB/c-mouse origin and syngeneic sarcoma L-1 cells indicated that L-fucose specific lectin-like adhesion molecules, presumably situated on pulmonary cell surfaces are (at least partly) responsible for the specificity of this cell-cell interaction. Addition of specific sugars and glycoconjugates (L-fucose and fucoidan, respectively) to the incubation medium evidently inhibited the adhesion process as quantified using radiolabelled tumor cells. Unspecific carbohydrates (e.g. D-galactose) did not affect the cellular interaction. In vivo, repeated administration of fucoidan (but not of unspecific glycoconjugates) significantly inhibited the settling of metastatic sarcoma L-1 cells in the lungs of BALB/c-mice. Therefore, when lectin-like adhesion molecules on pulmonary cells were blocked with competitive glycoconjugates, tumor cell colonization of the lung could be significantly inhibited.

Animals↗

[Bacteriophage conversion as a factor modifying the intensity of phagocytosis of Staphylococcus aureus by human leukocytes].

Staphylococcus aureus NCTC 8325-4 and its eight variants lysogenized with phages responsible for the synthesis of staphylococcal staphylokinase were used for the study. Influence of phage conversion of S. aureus on its interaction with human leucocytes and influence of prophage on strain susceptibility to intracellular killing by human granulocytes without opsonins were evaluated. It was found that lysogenization of the strain with the bacteriophages decreased in each case reactivity of human leucocytes for staphylococcal strain what was expressed by lower bioluminescence values and by lower percentage of intracellular killing of bacterial cells carrying prophage.

Culture Media↗

[Preliminary evaluation of the diagnostic usefulness of bronchoalveolar lavage (BAL) in selected cases of interstitial lung diseases].

Diagnostic usefulness of BAL was assessed in 25 selected cases of interstitial lung diseases. There were 14 cases of allergic alveolitis, 6 cases of idiopathic pulmonary fibrosis and one case each of sarcoidosis, lymphangiomyomatosis, granulomotosis bronchocentrica, lymphogranulomatosis maligna, alveolitis of unknown etiology. BAL was assessed diagnostically usefull in 77% of the cases. More helpful was medical history which proved to be useful in all cases, and pulmonary function tests which were helpful in 84%. Lung biopsy was diagnostic in 66.6% of the cases, TBLB in 36.5%, while open lung biopsy carried out in 6 patients was diagnostic in 100%. Bronchoalveolar lavage is a useful element of diagnostic evaluation in patients with interstitial lung disorders, it is a safe method and well tolerated by the patients.

Adult↗

[Allergic alveolitis in rural inhabitants].

27 rural inhabitants with allergic alveoltis were evaluated in order to determine the diagnostic usefulness of clinical, radiological, functional examination, BAL, lung biopsy, presence of serum antibodies against environmental antigens in determining the diagnosis and clinical stage of the disease. The effect of therapy and exposition on lung function tests were also discussed. Corticotherapy in most of the patients produced an improvement of vital capacity. In part of the patients isolation from environmental antigens produced stabilization of respiratory parameters. Small dose continuous corticotherapy in patients with prolonged exposition proved to be beneficial and prevented occurrances of acute relapses, as well as decrease of respiratory functional parameters values.

Adrenal Cortex Hormones↗

Studies on a biological response modifying LYSAT from Propionibacterium avidum KP 40.

Propionibacterium avidum KP 40 cells were mechanically disintegrated in order to obtain the soluble immunostimulatory (antineoplastic) LYSAT. Chemiluminescence measurements of human leukocyte function yielded enhanced activation of the cells after incubation with 2.5 and 5 mg of LYSAT. As compared to non-treated controls, administration of LYSAT to BALB/c-mice (1, 2.5 and 5 mg; intraperitoneally, subcutaneously, intranasal; 7, 4 and 2 days prior to challenge) induced a significant enlargement of the spleen as well as significantly reduced sarcoma L-1 lung colonization 14 days after challenge and evidently enhanced chemiluminescence response of peritoneal macrophages.

Adjuvants, Immunologic↗

Granulocyte activating factor released from Propionibacterium acnes. A possible mediator of inflammation in acne vulgaris.

Incubation of Propionibacterium acnes but not of Propionibacterium granulosum or Propionibacterium avidum (for 30 min at 37 degrees C in physiological saline) released a soluble factor that produced enhanced chemiluminescence response of human granulocytes as well as increased chemotactic motility of these cells. Sephadex G-25 filtration of the granulocyte activating factor (GAF) revealed its low molecular weight and apparent peptide character. Thus, GAF may be a stimulus for inflammation in acne vulgaris since low molecular weight chemotactic factors can be expected to penetrate follicular walls.

Acne Vulgaris↗

Investigations on the opsonin-dependent interaction of Klebsiella bacteria and human polymorphonuclear leukocytes.

Encapsulated and nonencapsulated Klebsiella strains with different types of fimbriation were tested for their opsonin-dependent stimulation of human polymorphonuclear leukocytes (PMNs). Chemiluminescence (CL) of the PMNs was determined since CL-response can be used indirectly to quantitate phagocytosis. Apparently, the interaction between Klebsiella bacteria and human PMNs is dependent on the type of fimbration and on the presence of capsules. Evaluation of the bactericidal capacity of human PMNs against Klebsiella bacteria positively correlated with the chemiluminescence response demonstrating the importance of fimbriation and capsulation for this process, too.

Bacterial Adhesion↗

Intestinal microflora of BALB/c-mice and function of local immune cells.

BALB/c-mice were treated for 7 days with oral nonabsorbable dosages of mezlocillin to achieve digestive tract decontamination. Such a procedure resulted in rapid eradication of most species of aerobic and anaerobic intestinal microflora. Various functions of peritoneal macrophages (e.g. chemiluminescence response, chemotactic motility, bactericidal and cytostatic ability) and lymphocyte proliferation were decreased in decontaminated animals as compared to non-treated controls.

Animals↗

The role of plasmids in opsonin-independent Staphylococcus aureus-leukocyte interactions.

The opsonin-independent phagocytic and bactericidal activity of human polymorphonuclear leukocytes stimulated by two Staphylococcus aureus strains and their variants with differing plasmid patterns was investigated. Interactions between staphylococci and phagocytes were evaluated by chemiluminescence and intracellular killing tests. The results obtained indicate that the presence or absence of certain plasmids can modify staphylococcal phagocytosis and their susceptibility to intracellular killing. Pretreatment of the strains investigated with subinhibitory concentrations of mezlocillin and ofloxacin (10% MIC) influenced these parameters, too.

Humans↗

Antibiotic treatment, intestinal aerobic microflora and experimental sarcoma L-1 growth in Balb/c-mice.

The present paper deals with the influence of a 10 days treatment with mezlocillin, piperacillin, cefotaxime, clindamycin or gentamicin on the endogenous intestinal microflora of Balb/c-mice and on the local growth of sarcoma L-1 tumor. Clindamycin and gentamicin demonstrated no influence, whereas cefotaxime and piperacillin caused the eradication of gram-negative resp. gram-positive bacteria but these antibiotics didn't produce a growth inhibition of local L-1 sarcoma tumor. The oral or parenteral application of mezlocillin (a 3 days treatment was sufficient) eradicated the complete aerobic and anaerobic intestinal microflora. This effect was significantly correlated with an increase of the cecum weight and the inhibition of local tumor growth. Possible mechanisms of these effects are discussed.

Animals↗