Study of the Dynamics of Biofilm Formation and Elastase Activity of Pseudomonas aeruginosa in the Presence of Dodecanoyl-Homoserine Lactone.

We studied the effect of early accumulation of N-3-oxo-dodecanoyl-homoserine lactone on the suppression of Pseudomonas aeruginosa reproduction, biofilm formation, and elastase activity. N-3-oxo-dodecanoyl-homoserine lactone in various concentrations was added to the P. aeruginosa culture, and changes in the concentration of bacteria and the formation of biofilms were studied in dynamics. N-3-oxo-dodecanoyl-homoserine lactone in a concentration of 25 µM, decelerated proliferation of bacterial cells during the first 6 h of culturing (p<0.05) and stimulated biofilm formation after 18 h of culturing. Elastase activity of P. aeruginosa increased significantly after addition of N-3-oxo-dodecanoyl-homoserine lactone in a concentration of 0.75 µM.

Aerosol inhalation delivery of cefazolin in mice: Pharmacokinetic measurements and antibacterial effect.

Aerosol inhalation delivery of cefazolin, a broad-spectrum first-generation cephalosporin antibiotic, was investigated. Inhalation system based on ultrasonic nebulizer was developed for the generation of dry cefazolin aerosol within mean particle diameter range 0.5-3.0 µm and mass concentration 0.01-3 µg/cm3. Pharmacokinetic measurements were carried out for the aerosolized form of cefazolin delivered in mice using nose-only chamber. Cefazolin concentrations in blood serum and in the lungs of mice were measured as a function of time by means of high performance liquid chromatography. Body-delivered dose depending on particle size, concentration and inhalation time as well as other pharmacokinetic parameters were determined. The antibacterial effect of aerosolized cefazolin was assessed through the aerosol inhalation treatment of mice infected with Klebsiella pneumoniae. Survival rate for infected mice after the treatment with cefazolin aerosol demonstrated high antibacterial efficiency of the inhalation delivery of cefazolin in comparison with intraperitoneal delivery.

[Cyclic neutropenia: a disease or a syndrome?]. / Tsiklicheskaia neitropeniia, zabolevanie ili sindrom!

Peripheral blood and bone marrow morphology, blood and bone marrow lymphocyte subpopulation composition were studied in two children with cyclic neutropenia, using flow cytofluorometry, monoclonal antibodies, colony-forming capacity of granulocytic macrophagal precursors in semi-fluid agar. The studies were conducted in varying periods of the neutropenic cycle. Differences were revealed in immunohematologic parameters and clinical course of neutropenia in the two patients. The analysis of the literature data and the authors' own observations of the patients with cyclic neutropenia permitted a suggestion on high heterogeneity of pathogenetic mechanisms of this disease.

[Phenotyping of blood and bone marrow lymphocytes in children with primary immunologic deficiency]. / Fenotipirovanie limfotsitov krovi i kostnogo mozga u detei s pervichnoi immunnoi nedostatochnost'iu.

Subpopulational composition of peripheral blood and bone marrow lymphocytes was studied in 17 children with different forms of immunodeficiency, combined with hematological shifts (agammaglobulinemia--6, mucocutaneous candidiasis--2, selective IgG-deficiency--2, hyper-IgM syndrome--3, cephalo-oculocutaneous telangiectasia (COCT)--2, general, variable immunodeficiency--2 patients; neutropenia was observed in all the patients, lymphopenia--in 13, anemia-in 6 patients. Surface markers were assayed by flow cytofluorometry with monoclonal antibodies OKT3, OKT4, OKT8, OKB7, produced by "Ortho diagnostics". Changes characteristic of certain forms of primary immunodeficiency have been revealed in the subpopulational composition of peripheral blood and bone marrow lymphocytes: decreased helper potential in patients with general variable immunodeficiency, T-lymphocyte deficiency in patients with COCT increased number of phenotype T3 cells and decreased amount of B-cell in agammaglobulinemia patients. Significant heterogeneity has been noted in the parameters of hemogram, myelogram and in the subpopulational composition of peripheral blood and bone marrow lymphocytes in each nosologic form, the group of patients with hyper-IgM syndrome has proved to be most heterogeneic. It has been suggested that the changes in the subpopulational composition of bone marrow lymphocytes may be responsible for primary immunodeficiency and disorders in hemopoiesis.

[Lymphocyte subpopulations in the bone marrow of children]. / Subpopuliatsii limfotsitov kostnogo mozga u detei.

Blood lymphocyte subpopulations, and bone marrow aspiration and biopsy materials were comparatively investigated in 10 children without hematologic or infectious diseases (the children had chest deformations and diaphragmatic hernias). Lymphocyte typing was conducted by the method of continuous cytofluorometry in a complete leucocyte suspension with the use of monoclonal antibodies. The results of the study have evidenced that the content of lymphocytes carrying T-cell markers in the aspiration material was twofold lower, and in the biopsy material fourfold lower than in the peripheral blood. The number of immature T-lymphocytes in the bone marrow is higher than their content in the peripheral blood. A total of 40% of aspiration cells and 60% of biopsy cells present in the lymphocytic window, do not carry lymphocytic markers. CD8+-lymphocytes prevail in the bone marrow.

[Lipid granularity and topographic characteristics of renomedullary interstitial cells in genetically spontaneous hypertension in rats]. / Lipidnaia granulirovannost' i topograficheskie osobennosti renomedulliarnykh interstitsial'nykh kletok pri geneticheskoi spontannoi gipertonii u krys.

Light microscopy was used to study lipid granularity of the renomedullary interstitial cells (IC) in spontaneously hypertensive rats (SHR) aged 4 months and in Wistar rats (control) of the same age. Altogether 2000 IC were examined per animal on an average. The concentric distribution of the granular IC in the renal papilla was demonstrated. Lipid granularity of the IC was discovered to be lowered and the zone of granular IC to be enlarged in the whole papilla in SHR rats as compared with control. Also, the differences were found in lipid granularity of the IC in individual zones of the papilla in both SHR and normotensive animals, which seems likely to indicate different functional significance of the individual parts of the renal papilla.