[Pharmacological prevention of fibrosis in dacryosurgery]. / Medikamentoznaya profilaktika fibrotizatsii v dakriokhirurgii.

Chronic inflammatory process in the lacrimal drainage system is the main etiological factor leading to dacryostenosis and consequent obliteration - partial and total nasolacrimal duct obstruction. Prevention of this process is an urgent problem in dacryology. Currently, there is very little research on the development and use of conservative methods for treating dacryostenosis using anti-inflammatory, as well as anti-fibrotic drugs. In this regard, the main method of treating lacrimal drainage obstruction is dacryocystorhinostomy. However, the problem of recurrence after this operation has not been resolved. The causes of recurrence can be cicatricial healing of dacryocystorhinostomy ostium, canalicular obstruction, formation of granulations and synechiae in its area. Surgical methods of recurrence prevention are associated with possible complications, and there is conflicting data on the feasibility of their use. Based on this, the development of pharmacological methods for the prevention of fibrosis in dacryology is promising, among which the antitumor antibiotic Mitomycin C is the most studied. However, there are no specific scientifically substantiated recommendations for the use of this drug, and the data on its effectiveness vary. This has prompted researchers to look for and study alternative anti-fibrotic agents, such as antitumor drugs, glucocorticoids, hyaluronic acid, small molecule, biological, immunological and genetically engineered drugs, as well as nanoparticles. This review presents the current data on the efficacy and prospects of the use of these drugs in dacryology.

Evaluation of the Efficiency of Lytic Mycobacteriophage D29 on the Model of M. tuberculosis-Infected Macrophage RAW 264 Cell Line.

Culture of mouse macrophages (RAW 264.7 ATCC strain) in wells of a 6-well plate was infected with M. tuberculosis in proportion of 15 mycobacteria per one macrophage and then treated with a lytic strain of mycobacteriophage D29. Antibacterial efficacy of mycobacteriophages was studied using D29 phage (activity 108 plaque-forming units/ml) previously purified by ion exchange chromatography. After single and double 24-h treatment, the lysed cultures of macrophages were inoculated onto Middlebrook 7H10 agar medium. The number of mycobacterial colonies in control and test wells (at least 3 wells in each group) was 300.178±12.500 and 36.0±5.4, respectively (p<0.01).

[The application of lytic micro-bacteriophage В29 for accelerated phenotype detection of sensitivity mycobacteria of tuberculosis to anti-tuberculosis medications.]

In conditions of prevalence of medicine-resistant strains of mycobacteria of tuberculosis necessity in accelerated, including phenotype techniques of detection of sensitivity of mycobacteria to anti-microbial chemotherapeutic medications in clinical samples is an actual issue. The results of application of accelerated phenotype techniques of detection of sensitivity of clinical strains of mycobacteria of tuberculosis to anti-microbial chemotherapeutic medications on the basis application of lytic mycobacteriophage D29 are presented. The principle of technique is in evaluation of reproduction of mycobacteriophage in cells of mycobacteria of tuberculosis in presence of sensitive to them anti-bacterial medications. The reproduction of mycobacteriophage is evaluated by quantitative analysis of phage DNA in polymerase chain reaction in real-time. The study used 102 clinical strains of mycobacteria of tuberculosis obtained after primary cultivation or re-cultivation in tubes of MGIT system (Bactec). After positive results of growth of mycobacteria of tuberculosis were obtained, the samples were incubated during 48 hours in CO2 incubator in the presence of critical concentrations of 10 widely applied in case of treatment tuberculosis medicinal substances in liquid nutrient medium Middlebrook 7H9 enriched with components OADC, in format of 24 well cultural plate with volume of nutrient medium 1 ml per well. Whereupon, in plate wells deposited 2x103 plaque-forming units of mycobacteriophage D29. After 24 hours a qualitative detection of phage DNA was implemented with polymerase chain reaction in real-time using reagents phage D29 ("Syntol", Russia). The increasing of threshold level of fluorescence of Ct more than to 2 cycles in samples with antibiotic as compared with control testifies sensitivity of the analyzed strain of mycobacteria of tuberculosis to antibiotic. The level of coincidence made up to 91% in comparative study with inoculation in Lowenstein-Jensen nutrient medium. The level of coincidence made up to 96% in comparative study with Bactec test-system of limited number of strains with establishment of sensitivity for 10 medications. The data was confirmed concerning inverse relationship of value ∆Ct and minimal inhibiting concentration of medication. The supposed high efficiency of possible reagents' set on the basis of presented technique on cost/quality criterion.

SRPES and STM data for the model bimetallic Pd-In/HOPG catalysts: Effects of mild post-synthesis oxidative treatments.

Post-synthesis treatment of bimetallic catalysts in different gas phases resulting in the adsorption-induced segregation is among promising approaches to enhance their activity not compromising selectivity towards a number of low-temperature reactions. Our recently published paper (M.A. Panafidin, A.V. Bukhtiyarov, I.P. Prosvirin, I.A. Chetyrin, A.Yu. Klyushin, A. Knop-Gericke, N.S. Smirnova, P.V. Markov, I.S. Mashkovsky, Y.V. Zubavichus, A.Yu. Stakheev, V.I. Bukhtiyarov, A mild post-synthesis oxidative treatment of Pd-In/HOPG bimetallic catalysts as a tool of their surface structure fine tuning. Appl. Surf. Sci.) reports on Pd-In intermetallic formation regularities and their evolution after storage in air as well as during treatment in oxygen at submillibar pressures. The current paper gives an extended representation of experimental ex situ/in situ synchrotron-based photoelectron spectroscopy (SRPES) and scanning tunnelling microscopy (STM) data used to derive scientific conclusions in the paper quoted above.

Ultrastructure of Chlamydia pneumoniae in cell culture.

The electron microscopic appearance of Chlamydia pneumoniae elementary bodies with pear-shaped, loose outer membrane has been suggested as one criterion of its classification as a new chlamydial species. The study of the original strain TW 183 in LCL 929 and HL cells and a low-passage isolate of Kajaani-6 isolate in HL cells revealed spherical compact elementary bodies common to other chlamydia.

Sorption of noble-metal ions on silica with chemically bonded nitrogen-containing ligands.

A study has been made of the sorption of Ir(IV), Rh(III), Pt(IV), Ru(IV), Os(VIII), Pd(II) and Au(III) from aqueous solutions by silica chemically modified with nitrogen-containing organic ligands, as a function of hydrochloric acid concentration, time of contact, concentration of the element and the ionic strength. Sorption of noble-metal ions at pH > 1 on a sorbent containing monoamine groups seems to be due to a complexation mechanism, and to an anion-exchange mechanism at pH < 1. With aminopropyl-silica 1000-fold concentration of Ir(IV) and Rh(III) from their 10(-8)-10(-7)M solutions was achieved and these metals were subsequently determined on the sorbent surface by X-ray fluorescence. Detection limits were 10-20 ng/ml. There was no interference from 1000-fold quantities of non-ferrous metal ions and Fe(III). With the sorbent containing bonded diethylenetriamine groups, 1000-fold concentration of Au(III) was achieved, and it was then determined on the sorbent surface by an atomic-emission method. Conditions for desorption of Au(III) with pyridine and potassium thiocyanate were developed.

Peculiarities of Rickettsia prowazekii in the cell culture as revealed by cryoultramicrotomy.

Ultrastructure of Rickettsia prowazekii has been followed in L-929 cells 4 days post-infection (p.i.) by cryoultramicrotomy. Groups of rickettsiae were present in the cytoplasm outside of vacuoles forming microcolonies. The size of rickettsiae amounted to 400 X 700 nm, the average thickness of the cell wall was 5 nm, that of periplasmic space and cytoplasmic membrane 14 and 6 nm, respectively. Within intracytoplasmic colonies the rickettsiae were tightly packed and their cell walls were closely adjacent to each other. No halo or capsule-like coating around them was detected. No ultrastructural details were observed in the light translucent spaces between cells. Marginal rickettsiae of the microcolonies were often in close contact with the host cell mitochondria.

Ultrastructure of Rickettsia sibirica during interaction with the host cell.

Rickettsia sibirica (strain Netsvetaev) was found within large translucent spaces in the cytoplasm of L-929 cell monolayer cultures on day 6 postinfection (p.i.). These rickettsiae were rod shaped 0.3 X 10 microns in size encircled by a halo of up to 200 nm wide corresponding to a capsule-like coat. Directly on the cell wall was a 12 nm thick microcapsule in which subunit structures with 12 nm thick spacing could be recognized. The cell wall membrane was 14 nm thick with a wider internal layer occasionally in a section found split into two electron-dense lamels; the internal layer corresponded to peptidoglycan. The periplasmic space with an average thickness of 5 nm separated the cell wall from a 7 nm thick cytoplasmic membrane. The ultrastructure of R. sibirica was similar to that of other rickettsiae, although the capsule-like coat was thicker than in spotted fever (SF) group rickettsiae.

Persistence of Rickettsia prowazekii in cotton rat macrophage cultures.

Rickettsia prowazekii is able to multiply and persist for a long time in cotton rat macrophage culture (29-days observation period). Electron microscopic studies showed that the structure of Rickettsiae remained intact at different intervals post-inoculation (p.i.). In the course of persistence Rickettsiae revealed a reduced capacity to infect chick embryos and guinea pigs, however, the infectious agent could be isolated at all stages of persistence of cultured cells such as fibroblasts of the guinea pig embryo, macrophages of intact cotton rats.

Methods for purification of Rickettsia prowazekii separated from the host tissue: a step-by-step comparison.

Two methods for purification of Rickettsia prowazekii strains E, E Vir, and Breinl grown in chick embryo yolk sacs are described. These methods combine either differential centrifugation or sucrose mix, centrifugation through sucrose cushion, 10 mmol/l MgCl2 treatment, filtration through a glass filter AP-20 and 2 cycles of verografin discontinuous density gradient centrifugation. The purification procedure including sucrose mix allowed to recover about 38-42% biologically active rickettsiae, a yield which was by 10% higher than that obtained by the method beginning at differential centrifugation. The rickettsiae free of host cell components preserved their infectious activity. The obtained biomass was suitable for immunological and biological characterization of Rickettsia prowazekii and for isolation of its total DNA.

Electron microscopic analysis of in vitro interaction of Rickettsia prowazekii with guinea pig macrophages. II. Macrophages from immune animals.

Alike to macrophages from intact animals, reproduction, destruction and formation of spheroplast-like forms were observed in macrophages from immune guinea pigs 2 months post-infection (p.i.) with the virulent Breinl strain of Rickettsia prowazekii. Unlike to the former, immune macrophages revealed phagolysosomes which were larger in size and contained more rickettsiae showing morphologic signs of destruction. Spheroplast-like forms occurred more often and were more numerous than in intact animals. Structures morphologically similar to L-forms of gram-negative bacteria and that of chlamydiae were also detected. After adding immune serum, more intact rickettsiae and spheroplasts were found in phagosomes as well as more phagolysosomes contained rickettsiae and spheroplasts with morphologic signs of destruction. It is suggested that clearance of immune macrophages from rickettsiae is mediated by at least two processes: on one hand by destruction of rod-shaped rickettsiae within phagolysosomes and, on the other hand, by formation and subsequent destruction of spheroplast-like forms within vacuoles, which probably also function as phagolysosomes.

Electron microscopic analysis of in vitro interaction of Rickettsia prowazekii with guinea pig macrophages. I. Macrophages from nonimmune animals.

Monolayer cultures of peritoneal macrophages of intact guinea pigs were infected with Rickettsia prowazekii (strain Breinl) and examined by electron microscopy after 30 min, 4 and 24 hr post-infection (p.i.). Three parallel processes developed in infected macrophages: reproduction of rickettsiae in macrophage cytoplasm, destruction in phagolysosomes and production of spheroplast-like forms. Reproduction of rickettsiae yielded 2 cell types: those with dense and with light cytoplasm; they were located side by side in the microcolony and seemed to have a common capsule-like coat. Relatively small spheroplast-like forms of about 1 micron in size were regularly detected. Addition of immune serum to macrophages increased the number of rickettsiae, both of rod-shaped as well as of spheroplast-like ones located within phagosomes, but elicited no increase in the number of digested pathogen cells.

[The sensitivity of a number of cell cultures to different strains of Rickettsia prowazekii]. / Chuvstvitel'nost' riada kletochnykh kul'tur k razlichnym shtammam Rickettsia prowazekii.

The sensitivity of some cell cultures to different R. prowazekii strains (strain E with low pathogenicity, virulent strain Breinl, strains ERifRI and EVir) has been studied with a view to the selection of an adequate culture for growing these strains and the study of their biological properties. Experiments on titration in cells have revealed that 6- to 7-day primary and secondary irradiated quail fibroblasts and human amnion cells FL show the maximum sensitivity to all strains under study, comparable to that of chick embryos. The sensitivity of 6- to 7-day primary and secondary irradiated chick fibroblasts is faintly pronounced, and 24-hour chick and quail fibroblasts are still less sensitive. Cells FL have shown high sensitivity to strain E and mutant ERifRI in prolonged subculturing for 140 and 63 days (the term of observation) respectively after a single inoculation.

[Serotype characteristics of clinical strains of Pseudomonas aeruginosa]. / Kharakteristika serotipov klinicheskikh shtammov Pseudomonas aeruginosa.

A total of 348 P. aeroginosa strains isolated from patients with pulmonary and pleural diseases were studied, and 87% of the test showed the possibility of their serotyping with the use of group-specific agglutinating antisera. Serogroups II, III, IV were found to be prevalent among the strains isolated from patients with bronchopulmonary pathological states. Correlations between definite groups of P. aeroginosa in their sensitivity to antibiotics were established; thus, the cultures belonging the serogroups II, III, IV were found to be more sensitive to tetracycline annd chloramphenicol than the culture belonging to other serogroups.

[The surface antigens of Rickettsia prowazekii studied with monoclonal antibodies]. / Izuchenie poverkhnostnykh antigenov Rickettsia prowazekii pri pomoshchi monoklonal'nykh antitel.

R. prowazekii antigens have been tested with the use of monoclonal antibodies (McAb) to different epitopes of the microorganism. As revealed in these tests, McAb B4/4 and A-3/D, active against species-specific thermolabile antigen, interact with protein having a molecular weight of 90-120 KD. McAb C5/2, active against thermostable group antigen common with that of Rickettsia typhi, interact with LPS-like antigen having a molecular weight of 30 KD. Ultrastructural immunochemical studies have revealed that both R. prowazekii antigens are located on surface structures of rickettsiae, such as the microcapsule and cell wall.

[The ultrastructure of a new species of Chlamydia--Chlamydia pneumoniae]. / Ul'trastruktura novogo vida khlamidii--Chlamydia penumoniae.

The dynamic study of a new Chlamydia species, C. pneumoniae (strain TWAR, isolate TW-480), inoculated into the monolayer culture of cells L-929 was made 24, 48, 72 and 96 hours after inoculation. When compared with C. trachomatis and C. psittaci, C. pneumoniae were found to stand between these two species with respect to the morphology of their intracytoplasmic microcolonies (inclusions): they were round, almost bubble-like, but more densely packed with chlamydiae, surrounded by an undulate membrane, preserving its integrity until the late stages of their development cycle. In cells L-929 C. pneumoniae had a typical development cycle accompanied by the formation of vegetative and spore-like cells, reticular and elementary bodies, as well as intermediate cells, though this process was slower than in C. trachomatis and C. psittaci. Besides normal elementary bodies, many altered ones were formed in the process of the development of C. pneumoniae in cells L-929. Most of these alterations were similar to the process of bacterial L-transformation and could be regarded as the manifestation of chlamydial pathology related to the adaptation to new host cells.

[The ultrastructure of the interaction of Rickettsia sibirica and R. slovaca with the cells of ixodid ticks]. / Ul'trastruktura vzaimodeistviia Rickettsia sibirica i R. slovaca s kletkami iksodovykh kleshchei.

The ultrastructural aspects of the interaction of R. sibirica and R. slovaca with cells of mites of the species Dermacentor reticulatus, D. marginatus and Ixodes ricinus after their parenteral infection, as well as in the organs of D. marginatus infected naturally in the environment, have been studied. Both rickettsial species have similar morphology in different organs of the vector. These rickettsiae not only multiply, their populations are also partly destroyed in phagolysosomes. The natural mixed infection of R. sibirica and orbivirus in cells of D. reticulatus is described. As shown in this study, both associates pass through the complete ontogenetic cycle of development on the level of the host body and also on the level of an individual cell.

[Mechanism of action of lomefloxacin on Mycobacterium tuberculosis]. / Osobennosti mekhanizma deistviia lomefloksatsina na mikobakterii tuberkuleza.

The peculiarities of the mechanism of the lomefloxacin bactericidal action on Mycobacterium tuberculosis were studied. The electron microscopy of ultrathin sections of the cells of M.tuberculosis H37Rv exposed to 10 micrograms/ml of lomefloxacin for 24 hours revealed severe changes in their ultrastructure: exfoliation of the cell wall from the cytoplasmic membrane, loosening and fragmentation of the cytoplasmic membrane, lowering of the cytoplasm thickness, vacuolization and twisting of the mesosomes. The exposure of the cells to lomefloxacin for 72 hours resulted in their complete destruction: the cells proved to be a mass of unidentifiable fragments. Some destructions such as exfoliation of the intracytoplasmic membrane and the cytoplasm loosening and vacuolization were observed in the tubercle bacilli localized inside the phagosomes of the murine lung macrophages exposed to lomefloxacin. Such destructions were evident of the antibiotic good penetration not only into the macrophages but also through the phagosome walls as well as of the lomefloxacin intracellular bactericidal activity. In the experiments with the culture of the lung tissue from the tuberculosis foci of mice the basic mechanism fo the lomefloxacin action on M.tuberculosis was demonstrated: the lomefloxacin bactericidal effect was realized through the pathway of mechanism A of the antimicrobial action of fluoroquinolones.

[Comparison of nitrate reductase and automatic BACTEC MGIT 960 AST techniques for determining the drug sensitivity of mycobacteria tuberculosis]. / Sravnenie nitratreduktaznogo i avtomatizirovannogo BACTEC MGIT 960 AST metodov opredeleniia lekarstvennoi chuvstvitel'nosti mikobakterii tuberkuleza.

The accelerated nitrate reductase method (NRM) developed at the Central Research Institute of Tuberculosis versus the automatic assay of drug sensitivity by means of a BACTEC 960 bacteriological analyzer was assessed. NRM was carried out, by using the Lówenstein-Jensen medium for 10 days. It is based on the detection of alive Mycobacteria tuberculosis, by recording their enzymatic activity. The study showed a good agreement of the results obtained by NRM with those obtained on a BACTEC 960 analyzer. Agreements were found for 52 isolates in 47 (90.4%) cases, the results disagreed in the testing of 5 (9.6%) cultures. The results of NRM were identical to those for 21 of the 22 cultures sensitive on a BACTEC 960 device; the coincidence was 95.5%. The sensitivity of NRM ranged from 88.2% (for rifampicin) to 96.3% (for isoniazid) and the specificity did from 96% (for isoniazid) to 100% (for streptomycin, rifampicin, and ethambutol). The positive prognostic value of NRM was 100% (for streptomycin, rifampicin, and ethambutol) and 96.3% (for isoniazid). The negative prognostic value of NRM ranged from 94.6 to 96.8% for individual drugs. The efficiency of NRM (a ratio of the number of correct results to the total number of results) was greater than 0.96, which suggests that this method and the BACTEC MGIT 960 AST technique may be regarded as rather comparable. The testing of NRM versus the automatic BACTEC MGIT 960 AST technique has indicated that the former may be successfully used to determine the sensitivity of Mycobacteria to the critical concentrations of first-line antituberculous agents.