Magnetoplasmonic crystal waveguide.

We propose a perspective type of insulator-metal-insulator magnetoplasmonic crystal waveguide, composed of a gold grating placed between two garnet layers. Using an original non-perturbing method for the deposition of the upper magneto-dielectric layer, we fabricate the samples and provide experimental results evidencing the coupling of surface plasmon-polaritons propagating on the opposite Au/garnet interfaces. In contrast to traditional Au/garnet magnetoplasmonic crystals, spectra of the magneto-optical effect measured in transmission through this waveguide demonstrate rather specific features: a high-quality resonance for the long-range surface plasmon-polariton and a broad 60 nm wide resonance for the short-range surface plasmon-polariton. Our findings open new routes towards the development of high-sensitivity robust magnetoplasmonic sensors.

[Characteristics of gram-negative microflora on environmental objects in puerperal wards and their resistance to antibacterial preparations and disinfectants]. / Kharakteristika gramotritsatel'noi mikroflory ob''ektov okruzhaiushchei sredy poslerodovykh otdelenii i ee rezistentnost' k antibakterial'nym preparatam i dezinfektantam.

The species composition of gram-negative opportunistic bacteria isolated from different objects at three puerperal wards of a maternity clinic was studied. Escherichia coli and Acinetobacter were found to have a fairly wide circulation. The objects most contaminated by these bacteria were determined. The study showed that up to 33.3% of the isolated hospital strains of gram-negative bacteria were characterized by multiple resistance to antibiotics used in medical practice and to sulfathiazole. The strains showed the highest sensitivity to gentamicin and kanamycin. Most of the hospital strains were sensitive to chloramine and nirtan, but 4-13% of Klebsiella and Pseudomonas aeruginosa strains showed enhanced resistance to 0.1% chloramine solution.

[Cytotoxic effect on L-cells of lymphotoxin obtained during hypersensitivity of the delayed type to streptococcal antigens]. / Tsitotoksicheskoe deistvie na L-kletki limfotoksina, poluchennogo pri giperchuvstvitel'nosti zamedlennogo tipa k antigenam streptokokka

A study was made (in vitro) of the cytotoxic action on the mouse L-cells of lymph otoxin obtained in cultivation with a thermostable fraction of streptococcus of the lymph node cells of guinea pigs with hypersensitivity of delayed type to the streptococcus antigens. The cytotoxic action was determined by the calculation of the number of the L-cells preserved in the monolayer after the action on it of a decanted fluid containing lymphotoxin. A marked cytotoxic action on the L-cells was produced only by decanted fluids obtained in cultivation of lymph node cells of guinea pigs sensitized by streptococcus culture with a specific antigen. In cultivation of lymphoid cells of the same animals with a nonspecific antigen (tuberculin) the decanted fluids produced no significant cytotoxic action on mous fibroblasts. The value of the cytotoxic effect depended on the dose of the thermostable fraction, with which the lymph node cells were incubated in the preparation of the decanted fluid, and also on the concentration of the lymph node cells in the initial suspension.

[The effect of blood serum components on the growth, biochemical and biological properties of streptococcus]. / Vliianie komponentov syvorotki krovi na rost, biokhimicheskie i biologicheskie svoistva streptokokka.

The components of cattle blood serum, added to the medium for the cultivation of group A streptococci, considerably decrease the period of adaptation and increase the balanced growth rate of streptococci, which is manifested by changes in the surface structures of the cell wall: the absence or modification of protein M. Streptococci grown under these conditions lose their capacity for phagocytosis, and from the cell walls obtained from these streptococci no surface protein M can be isolated by pepsin treatment. Nevertheless, the ratio of the main cell-wall components (proteins, polysaccharide and peptidoglycan), the amino acid composition, as well as the resistance of the cell walls to the action of trypsin and endo-N-acetylmuramidase are the same in M+ and Mx variants, that makes it possible to infer that the modification of protein M or the inhibition of its synthesis occurs during the growth of streptococci in the presence of blood serum components.

[The pharyngeal beta-hemolytic streptococcal carrier state among blood donors]. / Glotochnoe nositel'stvo beta-gemoliticheskikh streptokokkov sredi donorov krovi.

459 blood donors aged 18-50 years were examined in 1987-1988 in Moscow. Among them, carrier state with respect to beta-hemolytic streptococci was detected in 107 donors (23.3%). The number of carriers gradually decreased with the increase of age of the examined donors. Group C streptococci occurred least of all (6.9%). Group A beta-hemolytic streptococci were isolated in 16.7% of the carriers. The isolation rate of streptococci from blood achieved its maximum in autumn and winter months and did not depend on preceding diseases, unhealthy working conditions, the rhesus factor and, with the exception of group A streptococci, the blood group. Among tonsillectomized donors carrier state with respect to beta-hemolytic streptococci occurred 2.2 times less frequently than among donors who had not undergone tonsillectomy. Carrier state with respect to beta-hemolytic streptococci was accompanied by higher levels of salivary sIgA antibodies to polysaccharide A, serum antibodies to polysaccharide A and circulating polysaccharide A. All beta-hemolytic streptococci were sensitive to erythromycin. All groups of streptococci showed the highest percentage of cultures resistant to gentamicin and tetracycline. In 100% of cases group A streptococci were sensitive to benzylpenicillin, methicillin, ampicillin, erythromycin and lincomycin.

[Antibiotic sensitivity of streptococci of the A, B, C and G serogroups isolated in 1987-1990]. / Chuvstvitel'nost' k antibiotikam streptokokkov serologicheskikh grupp A, B, C, i G, vydelennykh v 1987-1990gg.

Antibiotic susceptibility of 1114 cultures of beta-hemolytic streptococci belonging to serogroups A, B, C and G was tested. The cultures were isolated from healthy and diseased children and adults. Group A, C and G streptococci were shown to be highly susceptible to beta-lactams, erythromycin, lincomycin, chloramphenicol and ristomycin. Erythromycin, lincomycin, ristomycin and ampicillin (a beta-lactam) proved to be the most active antibiotics against group B streptococci. Streptococci of the four groups had low susceptibility to tetracycline and especially gentamicin. The different antibiotic susceptibility of the streptococcal cultures isolated from the diseased and healthy children and adults is discussed.

[Cytotoxic effect of lymphotoxin on a culture of macrophages]. / Tsitotoksicheskoe deistvie limfotoksina na kul'turu mikrofagov

Results of study of the cytotoxic effect of the lymphotoxin on the monolayer culture of the peritoneal macrophages used as target cells are presented. The lymphotoxin was obtained following an 18-hour incubation of the lymph node cells of guinea pigs with delayed hypersensitivity to tuberculoproteins, in the presence of the specific antigen (tuberculin). It was shown that only on the 5th--6th day of cultivation did the supernatants destroy more than half of the macrophages in 70% of the experiments. The death of the macrophages during the later periods of cultivation, in comparing with the L-cells, suggests a different resistance of these target-cells to the cytotoxic effect of the lymphotoxin.

[Death of adhering spleen cells (macrophages) in vitro in delayed hypersensitivity to microbial antigens]. / Gibel' prilipaiushchikh kletok (makrofagov) selezenki in vitro pri giperchuvstvitel'nosti zamedlennogo tipa k mikrobnym antigenam.

The cytotoxic action of immune lymphocytes on the adhering cells of the spleen obtained from guinea pigs sensitized and nonsensitized with BCG was studied in autologous and allogenous systems. A low cytotoxic effect revealed in cultivation with tuberculin of a suspension of spleen cells obtained from sensitized guinea pigs increased considerably after addition of lymph node cells from the same animal. Determination of death of the adhering cells of the spleen, as well as of the adhering cells of the lymph nodes could be used as a sensitive method for detection of hypersensitivity of a delayed type. Use of the splenic cells in the capacity of target cells is more convenient, since there are much more adhering cells in the spleen than in the suspension of lymph node cells.

[Morphological studies in delayed hypersensitivity to streptococcal antigens using film preparations of the mesentery]. / Morfologicheskie issledovaniia pri giperchuvstvitel'nosti zamedlennogo tipa k antigenam streptokokka s ispol'zovaniem plenochnykh preparatov bryzheiki.

Film preparations of the mesentery were used for morphological study of cell reactions, connected with the delayed type hypersensitivity (DTH). Twenty-four hours after intraperitoneal injection of small doses of the streptococcal thermostable fraction (TST fraction) the guinea-pigs sensitized with streptococcal culture developed a more intensive, as compared with control animals, diffuse infiltration of the peritoneum with mixed type cells (lymphocytes, monocytes and polynuclear leukocytes) abundant in mononuclear elements. With TST fraction dose build up the infiltration demonstrated an abrupt increase in polynuclear leukocytes completely masking the monocytic reaction in some cases. Large aggregations of lymphocytes were seen in the prelymph sinuses accompanying blood capillaries and nervous stemlets. Detection in the peritoneum of cell reactions characteristic of DTH following the injection of certain doses of specific antigens and comparative simplicity of obtaining film preparations allow recommending the technique described for disclosing and experimental study of DTH to microbial antigens.

[Proteins of bacterial membranes. NADH-dehydrogenase from the cells of Acholeplasma laidlawii]. / Belki bakterial'nykh membran. NADH-degidrogenaza kletok Acholeplasma laidlawii.

Using ion-exchange chromatography on DEAE-cellulose and gel filtration, a purified NADH-dehydrogenase was prepared from cell membranes of A. laidlawii. The enzyme specific activity exceeds the activity of the membrane preparation 45-fold. The enzyme is thermolabile and sensitive to lecithine. Electrophoresis of the enzyme preparation in the presence of Na-DS resulted in two proteins with Mr of 65 000 and 72 000. Specific staining of the gels with triphenyltetrasolium chloride in the presence of Triton X-100 revealed two protein bands, while in the presence of Triton X-100 and urea only one protein band was produced.

[Extraction of nontype-specific antigens of group A Streptococcus by potassium thiocyanate]. / Ekstraktsiia netipospetsificheskikh antigenov streptokokka gruppy A tiotsianatom kaliia.

A method for extraction of nontype-specific antigens of the group A streptococcus cellular wall from whole microbial cells is described. Potassium thiocyanate was used as an extracting agent. Nontype-specific antigens of the thiocyanate extract purified by ammonium sulfate precipitation were examined by immunodiffusion in agar gel. The thiocyanate extracts were found to contain several nontype-specific protein antigens part of which were absent from the HCl-extracts. No group A streptococcal polysaccharide was found in the thiocyanate extracts.

[Permeability of cutaneous macrophage lysosomal membrane in delayed hypersensitivity to streptococcal antigens]. / Pronitsaemost' membran lizosom makrofagov kozhi pri giperchuvstvitel'nosti zamedlennogo tipa k antigenam streptokokka.

The acid phosphatase (APh) was studied in the skin macrophage lysosomes of animals with delayed-type hypersensitivity (DTH) to the antigens of group A streptococci or tuberculoproteins. The histochemical procedure for the APh determination was employed in the skin sections without any preliminary tissue fixation. Intradermal injection of specific antigens in DTH proved to lead to the increase of the lysosomal membrane permeability in the skin macrophages. These data support the supposition that the lysosome enzymes of macrophages can act as factors causing tissue destruction in DTH.