Structure and luminescence properties of EuF3 and SrF2:Eu nanoparticles after microwave plasma annealing in "methane-hydrogen".

Recently, progress has been made in fabricating diamond-based scintillators with integrated rare-earth luminescent particles. These luminescent particles are integrated into the bulk of diamond during their synthesis by chemical vapor deposition (CVD). However, the growth conditions include a chemically aggressive plasma environment and elevated temperatures, which results in the partial degradation of particles and a decrease in the intensity of their luminescence. Here, we investigate the effect of thermal annealing of luminescent EuF3 and SrF2:Eu powders in microwave plasma that simulates the growth conditions of polycrystalline diamond. It was found that silicon substrates act as efficient reducing agents that lead to the partial reduction of trivalent europium to divalent europium. When annealing occurs on a diamond substrate, the reduction processes proceed at a significantly slower rate. The observed luminescence spectra showed both Eu2+ and Eu3+ luminescence bands, which allows for a targeted tuning of the luminescence spectrum of europium in composites and can be used to fabricate detectors and visualizers of X-ray radiation using a visible signal from the desired combination of Eu2±/Eu3± ions. During plasma annealing in pure hydrogen at moderate temperatures (600 °C), an intensive hydrogenation of particles is observed. Such hydrogen plasma treatment of fluorides may be considered a promising route to fabricate hydrides of various metals.

Impact of ligand-centered excited states on luminescence sensitization in Pr3+ complexes with ß-diketones.

In this study, two novel Pr3+ complexes with different 1,3-diketonate ligands were synthesized and investigated. To study the effect of the ancillary ligand on the energy transfer mechanisms in the complexes, a phenanthroline ligand was introduced. To take into account the influence of the ligand environment composed of different ligands on the energy transfer and relaxation processes, we compared the synthesized compounds with a similar complex containing the phenanthroline ligand. The spectroscopic studies in the visible and near-infrared spectral regions were supplemented with DFT and TD-DFT calculations. We found two ligand-to-ligand charge transfer (LLCT) states, with one state corresponding to energy transfer between 1,3-diketones and the other - to energy transfer from the 1,3-diketone to the phenanthroline motif. It was demonstrated that optical excitation via the latter channel leads to a fourfold increase in the luminescence quantum yield as compared with excitation via the π-π∗ transitions in 1,3-diketones. Moreover, both LLCT states provide sensitization of the Pr3+ luminescence involving the 3P0 and 3P1 levels.

[Rational approach to correction of intestinal microflora]. / Ratsional'nye podkhody k probleme korrektsii mikroflory kishechnika.

This paper reviews the present notions of the mechanisms of probiotics' action and analyzes selective approaches to correcting the intestinal microflora, such as the use of antibiotic-resistant and highly-adhesive probiotics, treatment with autostrains of lactobacilli and bifidobacteria, and the application of fermented-milk probiotics. Methods for optimization of the intestinal microflora in the newborns by using the maternal strains of bifidobacteria and the drug Zlemik that contains highly-adhesive lactobacilli are discussed. It is shown that parameters of immunotropic activity and involvement in the bacteriocin-mediated interactions may be used to design new probiotics. In future, the application of gene engineering methods will aid in designing a new generation of probiotics with predicted biological properties.

[The effect of "Solco" lactobacteria (Lactobacillus acidophilus) on the survival and microflora of mice with a Salmonella infection]. / Vliianie laktobakterii "Solko" (Lactobacillus acidophilus) na vyzhivaemost' i mikrofloru myshei pri sal'monelleznoi infektsii.

The Solco lactobacterial strain L. acidophilus Lat 11/83 has been used for the normalization of intestinal microflora in experimental post-infectious intestinal dysbacteriosis in mice. The results of experiments indicate that the intragastric administration of live Solco lactobacteria contributes to an increase in the survival rate of infected animals and the normalization of their gastrointestinal microflora. This strain may be used as a bacterial preparation for the regulation of intestinal microbiocenosis.

[Effect of human immunoglobulins on mouse intestinal microflora in dysbacteriosis]. / Vliianie immunoglobulinov cheloveka na mikrofloru kishechnika myshei pri disbakteriozakh.

Human immunoglobulins, injected into mice subcutaneously after their irradiation or at the beginning of antibiotic therapy, protected the mucous membrane of the proximal section of the small intestine from the penetration of enterobacteria. The formation of the protective barrier was observed when immunoglobulin preparations with the titer of antibodies to Escherichia coli O14 between 1:16 and 1:256 was used. The preliminary exhaustion of immunoglobulin preparations with E. coli strain O14 led to the complete loss of their protective properties.

[Modern methods for the evaluation of qualitative and quantitative changes in the characteristics of intestinal and vaginal microflora]. / Sovremennye metody otsenki kachestvennykh i kolichestvennykh pokazatelei mikroflory kishechnika i vlagalishcha.

Disturbances in normal intestinal and vaginal microflora in women have recently become quite frequent. This accounts for the need of bacteriological laboratories for introduction of reliable methods for the diagnosis of such disturbances. Correct methodological approaches to objective evaluation of the state of intestinal and vaginal microflora are described. The methods used in the study of anaerobic microflora (lacto- and bifidobacteria, eubacteria, peptostreptococci, clostridia, bacteriods, fusobacteria) and facultative anaerobic microorganisms (enterobacteria, staphylococci, streptococci, Gardnerella, fungi of the genus Candida) have been analyzed. All stages of the study are described in consecutive order: the transportation of the material under study, its treatment in a laboratory, the spectrum of selective nutrient media for the isolation of microorganisms, methods of their identification.

[The determination of the antagonistic activity of Solco lactobacteria (Lactobacillus acidophilus Lat 11/83) using gnotobiotic technology]. / Opredelenie antagonisticheskoi aktivnosti laktobakterii Solko (Lactobacillus acidophilus Lat 11/83) pri ispol'zovanii gnotobiologicheskoi tekhnologii.

Lactobacillus acidophilus strain Lat 11/83 has been used for the study of its antagonistic activity with respect to pathogenic microorganisms in experiments on conventional germ-free animals. The results of these experiments indicate that the above strain may be recommended as a highly active antagonist for the treatment and prophylaxis of intestinal dysbacteriosis of different etiology.

[The effect of a preparation made from Solco lactobacteria on the survival rate and intestinal microflora of irradiated animals]. / Izuchenie vliianiia preparata iz laktobakterii "Solko" na vyzhivaemost' i mikrofloru kishechnika u obluchennykh zhivotnykh.

Lactobacillus acidophilus strain Lat 11/83 Solco has been used for the normalization of intestinal microflora in experimental post-irradiation intestinal dysbacteriosis in mice. The results of these experiments indicate that live Solco lactobacteria, introduced intragastrically, facilitate the enhancement of the survival rate of irradiated animals and the normalization of microflora in their gastrointestinal tract. The strain can be used as bacterial preparation for the regulation of intestinal microbiocenosis.

[Principles of decontaminating the small intestine with bacterial preparations in experimental antibiotic dysbacteriosis]. / Printsipy dekontaminatsii tonkogo kishechnika bakterial'nymi preparatami pri antibiotikovom disbakterioze v ékpserimente.

Introduction of antibiotic-resistant bifidobacterial and lactobacterial strains, separately or together, does not decrease the degree and duration of contamination of the small intestine by enterobacteria after oral administration of antibiotics in large doses. The use of antibiotic-resistant bifidobacterial and lactobacterial strains allows one to decrease contamination of the small intestine by enterobacteria, resulting from the administration of antibiotics in near-therapeutic doses. The therapeutic effectiveness of bacterial preparations with respect to antibiotic dysbacteriosis has been found to depend on the level of resistance to the administered antibiotic. Antibiotic-resistant strains of bifidobacteria decrease the number of opportunistic microorganisms in the intestine in cases of dysbacteriosis caused by irradiation and administration of antibiotics.

[The microflora of the peritoneal exudate in patients with disseminated peritonitis]. / Izuchenie mikroflory peritoneal'nogo ékssudata u bol'nykh s rasprostranennym peritonitom.

In 11 patients with diffuse peritonitis and 39 patients with general peritonitis the microflora of peritoneal exudate and the sensitivity of isolated microorganisms to antimicrobial preparations were studied. The study revealed that in the total number of microorganisms isolated from peritoneal exudate enterobacteria prevailed in patients with diffuse peritonitis and bacteroids, in patients with general peritonitis. Enterobacteria were most sensitive to ciprofloxacin and claforan, while bacteroids, to ciprofloxacin; at the same time 15.4% of the bacteroid strains under study were resistant to ciprofloxacin.

[Effect of human immunoglobulins on microflora of the large intestine in nonspecific ulcerative colitis]. / Vliianie immunoglobulinov cheloveka na mikrofloru tolstogo kishechnika pri nespetsificheskom iazvennom kolite.

The use of commercial preparations of human immunoglobulin for the treatment of ulcerous colitis produces a positive effect on the microflora of the large intestine, contributing to the disappearance of Proteus, the lactose-negative forms of enterobacteria and the hemolytic variants of staphylococci, as well as to the increase of the amount of useful indigenous microflora (bifidobacteria and lactobacteria). The quantitative and qualitative improvement of the microflora leads, possibly, to the decrease of the intoxication of the body, improvement in the activity of the intestine and increased vitamin formation, thus giving a pronounced clinical effect and improvement in the endoscopic picture of the mucous membrane of the large intestine, peculiar for this disease.

[Joint use of antibiotics and antibiotic-resistant bifidobacteria in treating acute intestinal infections]. / Sovmestnoe ispol'zovanie antibiotikov i antibiotikoustoichivykh bifidobakterii pri lechenii ostrykh kishechnykh infektsii.

Acute dysentery and other acute intestinal diseases with obscure etiology are accompanied by pronounced intestinal dysbacteriosis which is manifested, on one hand, by the increased levels of Escherichia, enterobacteria, staphylococci and by the appearance of Klebsiella and Proteus in large amounts and, on the other hand, by an essential decrease in the number of lactic acid streptococci, lactobacteria, bifidobacteria. The treatment of dysentery and other intestinal diseases with obscure etiology with antibiotics, while eliminating the infective agent, leads to the aggravation of intestinal dysbacteriosis. The combined use of antibiotics and antibiotic-resistant bifidobacteria in intestinal infections with obscure etiology contributes to the effective restoration of normal intestinal microflora already in the process of antibiotic therapy.

[A new approach to selecting antibacterial preparations for treating patients with chronic urological infections]. / Novyi podkhod k podboru antibakterial'nykh preparatov dlia lecheniia bol'nykh khronicheskimi urologicheskimi infektsiiami.

The oral administration of microflora, isolated from the urinary tract or feces of urological patients, into the abacterial digestive tract of mice kept under the conditions of germ-free environment leads to the formation of the donors' microflora in the intestine of the recipient animals. Such recipient mice can be used as models for the rapid and highly reliable determination of the sensitivity of microflora in the patient's intestine and urinary tract to different antimicrobial preparations. In different patients such microflora, though similar in its qualitative and quantitative composition, differs in sensitivity to different antimicrobial preparations and their combinations. For the effective treatment of patients with chronic urinary tract infections a preliminary in vivo determination of the sensitivity of intestinal and urinary microflora to different combinations of antimicrobial preparations, carried out with the use of germ-free techniques, is necessary.

[Effect of normal and immune IgG, IgM and IgA on the intestinal microflora of mice with experimental dysbacteriosis]. / Vliianie normal'nykh i immunnykh IgG, IgM, IgA na mikrofloru kishechnika myshei pri éksperimental'nom disbakterioze.

Human IgG, IgM and IgA produce a pronounced protective effect, preventing enterobacteria from penetration into the mucous membrane of the proximal section of the small intestine of mice in antibiotic-induced dysbacteriosis. Normal mouse IgG and IgM, in contrast to IgA, are effective against mucosal enterobacteria of the small intestine. Immune mouse IgG, IgM and IgA show greater activity in protecting the mucous membrane than normal immunoglobulins of these classes.

[Sensitivity of the intestinal microflora of patients to antimicrobial preparations studied in order to conduct rational antibiotic treatment]. / Izuchenie chuvstvitel'nosti mikroflory kishechnika bol'nykh k protivomikrobnym preparatam s tsel'iu provedeniia ratsional'nogo lecheniia antibiotikami.

The oral administration of amikacin, ampiox, nystatin to CBA mice and the external treatment of the animals with 1% chlorhexidine solution makes it possible to create the germ-free state in the animals which must be then kept in a sterile box. If such animals receive the decantate of the patient's feces, introduced in a single administration, the microflora, which is subsequently formed in the intestine of the recipient animals, is identical to the donor's microflora. This permits the rapid and accurate determination of the sensitivity of the patient's intestinal microflora to different antimicrobial preparations and their combinations. The antibacterial preparations, effectively suppressing the patient's intestinal anaerobic opportunistic microflora in the intestine of the recipient mice, produce, if subsequently prescribed for treatment, a pronounced corrective effect on such microflora in the patient's intestine.

[Correction of intestinal microflora in chemotherapeutic dysbacteriosis using bifidobacterial and lactobacterial autologous strains]. / Korrektsiia mikroflory kishechnika pri khimioterapevticheskikh disbakteriozakh s pomoshch'iu autoshtammov bifidobakterii i laktobakterii.

The oral administration of kanamycin (40 mg/kg) or ampiox (500 mg/kg) to guinea pigs for 5 days led to disturbances in their normal intestinal microflora, manifested by a sharp decrease in the levels of lactobacteria and bifidobacteria, as well as by the appearance of large amounts of enterobacteria and enterococci, normally not detected in the proximal and distal sections of the intestinal tract. In adult volunteers receiving kanamycin orally in a dose of 40 mg/kg for 5 days disturbances in microbiocenosis also occurred: the amount of enterococci, staphylococci, lactobacteria and bifidobacteria considerably decreased, enterobacteria becoming the dominating microorganisms. Three oral administrations of bifidobacterial and lactobacterial autostrains immediately after the abolition of the antibiotic facilitated the rapid and effective restoration of the intestinal microflora.

[Study of the immunodepressive effect of passive immunization on a model of adaptive immunity]. / Izuchenie immunodepressivnogo deistviia passivnoi immunizatsii na modeli adaptivnogo immuniteta

The effect of various doses of specific serum administered in passive immunization on the formation of primary and secondary adaptive immunity in mice of the CBA strain was studied. Primary and secondary response was more sensitive to passive immunization on a model of adaptive immunity than in vivo. Most sensitive to the immunodepressive action of specific antibodies IgM and IgG were plaque-forming cells, and most resistant -- rosette-forming cells and cells. This led to a supposition that antibodies administered in passive immunization depressed the development of the immunological response acting at the level of T- and B cells.

[Microbial ecology of the vagina]. / Mikrobnaia ékologiia vlagalishcha.

In this review recent information on relationships between the vaginal environment and microflora, including new taxonomic groups of microorganisms, is updated. The role of normal microflora in formation of vaginal colonization resistance and possible participation of some representatives of normal microflora, mainly nonsporulating anaerobic organisms, in the development of perinatal, neonatal and gynecological infectious complications are considered.

[Characteristics of microorganisms colonizing human intestine]. / Kharakteristika mikroorganizmov, koloniziruiushchikh kishechnik cheloveka.

Introduction of novel methods of microbial diagnostics has considerably broadened our conceptions on the qualitative and quantitative variety of microorganisms inhabiting human gastrointestinal tract. In this review morphological and functional properties of obligate anaerobic bacteria (bifidobacteria, lactobacilli, eubacteria, peptostreptococci, clostridia, bacteroids, fusobacteria) and facultative anaerobic microorganisms (enterobacteria, staphylococci, streptococci, yeast-like fungi of the genus Candida) capable of colonizing human intestine are briefly characterized.

[The effect of new antimicrobial preparations used in combination with complete gnotobiotic isolation on the survivability and intestinal microflora of total-body irradiated mice]. / Izuchenie vliianiia novykh antimikrobnykh preparatov, primeniaemykh v komplekse s obshchei gnotobiologicheskoi izoliatsiei, na vyzhivaemost' i mikrofloru kishechnika total'no obluchennykh myshei.

The aim of these investigations was the study of the effect of different antimicrobial preparations on the survival rate and intestinal microflora of mice with experimental acute radiation sickness. These investigations revealed that the survival rate of the animals increased 3.1 times with the use of Supramycin, 2.4 times with the use of Tacef and 1.6 times with the use of Spizef and Pen-bristol. The study of the influence of these preparations on the intestinal microflora revealed that Spizef not only decreased the number of opportunistic microorganisms, but also led to a sharp drop in the level of lactobacteria. The use of Pen-bristol and Tacef led to practically complete elimination of enterobacteria enterococci, staphylococci, as well as lactobacteria. Supramycin essentially suppressed the number of opportunistic microorganisms and did not affect the level of lactobacteria. This was probably the cause of the highest effectiveness of Supramycin in comparison with Tacef, Spizef and Pen-bristol.