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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 EuF 3 and SrF 2 :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 Eu 2+ and Eu 3+ 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 Eu 2± /Eu 3± 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.

A series of cyclometalated complexes of ruthenium (II) with four different substituents in the aryl fragment of benzimidazole was synthesized in order to study the effect of substituent donation on the electronic structure of the substances. The resulting complexes were studied using X-ray diffraction, NMR spectroscopy, MALDI mass spectrometry, electron absorption spectroscopy, luminescence spectroscopy, and cyclic voltammetry as well as DFT/TDDFT was also used to interpret the results. All the complexes have intense absorption in the range of up to 700 nm, the triplet nature of the excited state was confirmed by measurement of luminescence decay. With an increase in substituent donation, a red shift of the absorption and emission bands occurs, and the lifetime of the excited state and the redox potential of the complex decrease. The combination of these properties shows that the complexes are excellent dyes and can be used as photosensitizers.

NIR emitting OLEDs (organic light-emitting diodes) with high photoluminescence quantum yields were developed on the basis of fluorinated 1,3-diketonate coordination compounds of the Nd 3+ ion. Both thermal evaporation and spin-coating techniques were successfully employed for active layer deposition resulting in electroluminescence quantum yields up to 1.38·10 -2 %. Blueish-green emission from exciplex and electroplax formations was almost suppressed with the topology optimization of the cell.

The interaction between diphenylacetylene and dichlorophenylphosphine under various conditions is a simple method for the preparation of pentaphenylphosphole derivatives exhibiting fluorescence properties. Depending on the electronic state of the various centers of the phospholic structure, it was possible to obtain molecules with fluorescence, as in the blue area for 1,2,3,4,5-pentaphenyl-2,5-dihydro-phosphole-1-oxide (H 2 PPPO), in the yellow area for 1,2,3,4,5-pentaphenylphosphole-1-oxide (PPPO) and in the cyan area for 1,2,3,4,5-pentaphenylphosphole (PPP). The effect of the structure and π-conjugation on the optical properties of these compounds was studied using PPP derivatives as examples. Unusual changes in the optical properties of PPP derivatives in solution and in the crystalline state are explained. In the case of agglomeration of PPPO and PPP molecules, the effect of aggregation-induced emission (AIE) was observed to have weak fluorescence in solution and strong fluorescence in the aggregated state. However, for H 2 PPPO, the AIE effect remains mild. With the help of experimental studies, supported by theoretical calculations, the main mechanism of the optical properties of pentaphenylphosphole derivatives has been revealed. It was observed that the intramolecular motions of PPPO and PPP are more limited in the solid state than the motions of H 2 PPPO, which is associated with less conjugation of the phenyl rotors of H 2 PPPO. The analysis of the structure and distribution of electron density showed why hydrogenation of the phosphole ring leads to a sharp change in the optical properties of pentaphenylphosphole derivatives, while the oxidation of phosphorus does not lead to the disappearance of the AIE effect and to a lesser extent affects the change in the fluorescence wavelength. Thus, it was shown how the regulation of various structural features of the phospholic ring helps to control the optical properties of such compounds.

A series of europium and gadolinium complexes comprising a β-diketone moiety modified with a fluorinated side-group and thiophene ring have been designed and synthesized and a comparative study of their luminescence properties has been carried out. In this study, when the methyl side group was modified by sequential addition of fluorine substituents and then the perfluorinated carbon chain was extended up to n -C 8 F 17 by adding CF 2 fragments, it transpired that the non-radiative energy processes are significantly suppressed in structurally more rigid polyfluorinated β-diketonate compounds of the series as C-H oscillators are replaced with low-energy C-F oscillators. The impact of other electron-withdrawing and electron-donating substituents on the spectroscopic and photophysical properties of the complexes in the present study has also been observed. Despite the presence of low-lying ligand-to-metal charge transfer states, the fluorinated Eu 3+ complexes proved to be bright luminophores capable of delivering ca. 50% quantum yield under UV radiation. The role of fluorination and carbon chain length was examined by using experimental spectroscopic methods and the results obtained were largely in good agreement with theoretical calculations (Judd-Ofelt theory analysis, and semiempirical quantum chemistry calculations) supporting our key experimental findings.

In this study, two novel Pr 3+ 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 Pr 3+ luminescence involving the 3 P 0 and 3 P 1 levels., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

A series of bis-cyclometalated iridium(iii) complexes with 2-arylphenanthroimidazole "antenna" ligands containing electron-donor or withdrawing substituents and a more flexible ancillary aromatic β-diketone bearing the "anchoring" carboxymethyl function has been prepared. Thorough X-ray study of the complexes revealed significant structural strains caused by bulky cyclometalated 2-arylphenanthroimidazoles resulting in dramatic distortions of the iridium octahedron and even in twist of the phenanthrene fragment. The crystal data were corroborated by gas-phase DFT calculations whereby the geometry of the complexes was distorted in the same way. While redox potentials, absorption and emission maxima of the complexes displayed expected change upon the variation of the electron-donating ability of the cyclometalated ligands, the complexes readily exchanged the bidentate ancillary ligand in the presence of a negligible amount of protons that was inspected in solution by UV-Vis spectroscopy. Moreover, after hydrolysis of the carboxymethyl group the resulting complexes readily react with the surface of titanium dioxide giving unique binuclear structures in which the deprotonated carboxy group of the coordinated β-diketonate binds the second bis-cyclometalated unit by forming a four-membered metallacycle. Though the enhanced reactivity of the complexes is contrary to the common idea of the high inertness of iridium(iii) compounds it can be seen as a consequence of the interplay between the steric hindrance induced by the ligands and the strong preference of the iridium(iii) ion for octahedral geometry. This study demonstrates that the use of bulky ligands provides access to light-harvesting iridium(iii) complexes with required extent of lability which may be promising as photocatalysts and biologically active molecules.

New fluorescent D-A-D dyes containing 9-( p -tolyl)-2,3,4,4a,9,9a-hexahydro-1 H -carbazole as a donor unit and 2,1,3-benzochalcogenadiazoles as an electron-withdrawing group were synthesized. The photoluminescent and electroluminescent properties of novel dyes for fluorescent OLED application were investigated. It was demonstrated that the replacement of lightweight heteroatoms by heavier ones enables the fine tuning of the maximum emission without significantly reducing the luminescence quantum yield. The maximum quantum yield value of 62.6% for derivatives based on 2,1,3-benzoxadiazole ( 1a ) in cyclohexane was achieved. Two devices with the architecture of glass/ITO/PEDOT-PSS/poly-TPD/EML/TPBi/LiF/Al (EML = emitting layer) were fabricated to check the suitability of the synthesized compounds as a single active emission layer in OLED. These OLEDs exhibited clear red electroluminescence of the dyes with the maximum current efficiency of 0.85 Cd/A.

Three novel lanthanide complexes with the ligand 4,4-difluoro-1-(1,5-dimethyl-1H-pyrazol-4-yl)butane-1,3-dione (HL), namely [LnL 3 (H 2 O) 2 ], Ln = Eu, Gd and Tb, were synthesized, and, according to single-crystal X-ray diffraction, are isostructural. The photoluminescent properties of these compounds, as well as of three series of mixed metal complexes [Eu x Tb 1-x L 3 (H 2 O) 2 ] (Eu x Tb 1-x L 3 ), [EuxGd 1-x L 3 (H 2 O) 2 ] (Eu x Gd 1-x L 3 ), and [Gd x Tb 1-x L 3 (H 2 O) 2 ] (Gd x Tb 1-x L 3 ), were studied. The Eu x Tb 1-x L 3 complexes exhibit the simultaneous emission of both Eu 3+ and Tb 3+ ions, and the luminescence color rapidly changes from green to red upon introducing even a small fraction of Eu 3+ . A detailed analysis of the luminescence decay made it possible to determine the observed radiative lifetimes of Tb 3+ and Eu 3+ and estimate the rate of excitation energy transfer between these ions. For this task, a simple approximation function was proposed. The values of the energy transfer rates determined independently from the luminescence decays of terbium(III) and europium(III) ions show a good correlation.

Varying the temperature of the reaction of [{Cd(pfb)(H 2 O) 4 } + n · n (pfb) - ], [Ln 2 (pfb) 6 (H 2 O) 8 ]·H 2 O (Hpfb = pentafluorobenzoic acid), and 1,10-phenanthroline (phen) in MeCN followed by crystallization resulted in the isolation of two type of products: 1D-polymers [LnCd(pfb) 5 (phen)] n · 1.5 n MeCN (Ln = Eu (I), Gd (II), Tb (III), Dy (IV)) which were isolated at 25 °C, and molecular compounds [Tb 2 Cd 2 (pfb) 10 (phen) 2 ] (V) formed at 75 °C. The transition from a molecular to a polymer structure becomes possible because of intra- and intermolecular interactions between the aromatic cycles of phen and pfb from neighboring tetranuclear Ln 2 Cd 2 fragments. Replacement of cadmium with zinc in the reaction resulted in molecular compounds Ln 2 Zn 2 [Ln 2 Zn 2 (pfb) 10 (phen) 2 ]·4MeCN (Ln = Eu (VI), Tb (VIII), Dy (IX)) and [Gd 2 Zn 2 (pfb) 10 (H 2 O) 2 (phen) 2 ]·4MeCN (VII). A new molecular EuCd complex [Eu 2 Cd 2 (pfb) 10 (phen) 4 ]·4MeCN (X)] was isolated from a mixture of cadmium, zinc, and europium pentafluorobenzoates (Cd:Zn:Ln = 1:1:2). Complexes II-IV, VII and IX exhibit magnetic relaxation at liquid helium temperatures in nonzero magnetic fields. Luminescent studies revealed a bright luminescence of complexes with europium(III) and terbium(III) ions.

The possibility of using a single light-emitting layer consisting of newly synthesized fluorescent small organic molecules of D-A-π-A type incorporated into a conductive matrix together with an electron conductive Alq 3 layer in order to form radiation in candle light-style OLEDs was shown for the first time. A record low color temperature of 1722 K OLED radiation was achieved, which is by 80 K lower than that of the best devices reported previously.

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.

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.

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 microbial status of the intestine and the influence of lavage with polyethylene glycol and balanced electrolyte solution (PEG + E), used in the process of the preparation of patients to polypectomy, on this status were evaluated. The study of microflora was made before oral lavage after, and 48-72 hours later its completion. For control, a group of healthy volunteers, also subjected to oral lavage with PEG + E, was used. The lavage of the digestive tract with PEG + E led to a sharp change in the microbial status in both groups. Some microorganisms, previously absent in the intestine, were found after lavage. The processes of the restoration of intestinal microflora after lavage in healthy volunteers and in patients with polyps had certain differences. In healthy volunteers intestinal microflora was completely restored, and even improved, 48-72 hours after lavage with PEG + E, while at the expiration of this time intestinal microflora in the patients with polyps could be characterized as dysbiotic.

The study of the microflora of the large intestine in healthy adult volunteers of different age groups (25-36, 55-68 and 88-94 years old), living in Switzerland, has been carried out. As revealed by the analysis of the result obtained in this study, normal intestinal microflora in adults has different qualitative and quantitative characteristics at different periods of their life. The greatest diversity of intestinal microflora is observed at a mature age (55-68 years old), while the poorest microflora is observed in people more advanced in age. The amount of microorganisms inhabiting the intestine reaches its maximum in people of mature age and is low in elderly people. Changes in normal intestinal microflora are probaly linked with morpho-functional transformations in the host body at different periods of life. It is expedient to work out the criteria of norm for the microflora of different age groups with a view to use these criteria for the evaluation of the microbial status of the intestine in persons of different age.

Intestinal microflora was studied in 3 groups of children; 55--living in Mongolia, 18--in Switzerland and 28--in Russia. Age of children of both sexual groups was 1.5-3 years. This study revealed that in none of these groups of clinically healthy children living in different regions and having different diet normal intestinal microflora corresponded to the standard considered to be the norm. The revision of norm criteria for normal intestinal microflora in children is recommended.

The study of intestinal microflora was made in clinically healthy young adults living in rural areas of Mongolia, in Russia (Moscow) and in Switzerland, as well as in Swiss citizens of elderly age groups (55-68 and 87-94 years). Essential differences in the quantitative and qualitative characteristics of intestinal microflora both in the inhabitants of different countries as well as in people belonging to different age groups in the same country were established. The results of the study demonstrated the expediency of working out the criteria of the norm for intestinal microflora both for the population of different countries and for people living in the same country, but belonging to different age groups.

15 pregnant women with pregnancy lasting 28-32 weeks, whose medico-laboratory data (the positive result of the amino test, high pH value and the detection of "key" cells) suggested the presence of bacterial vaginosis, were placed under observation. The bacteriological study of vaginal microflora in all these women revealed pronounced disturbances simultaneously with the development of intestinal dysbacteriosis. The local application of the bacterial preparation "Zhlemik" containing freeze-dried live lactic acid bacteria of vaginal origin and the oral administration of lactic acid bifidumbacterin containing live bifidobacteria of intestinal origin permitted the successful restoration of vaginal and intestinal microbiocenosis. The capacity of biotherapeutic preparations for inducing non-specific immunostimulation led to a significant rise in the levels of IgA, IgM and IgG in vaginal secretions.

Aerobic microbes in ENT departments were studied. The following strains were isolated: Staphylococcus, Streptococcus, Enterococcus, Acinetobacter, Klebsiella, Pseudomonas, Flavobacter, Citrobacter, Enterobacter, Escherichia, Aspergillus, Candida. 54.5% of the isolated strains were of hospital origin. Comparative evaluation of antibiotic resistance has shown a wide spectrum of resistance of the isolated microorganisms to antimicrobial drugs, among those to the drugs used in the ENT departments.

The vaginal microflora in 11 women suffering with bacterial vaginosis was corrected by BTA "Zlemik" contained highly adhesive strain Lactobacillus. BTA was administered intravaginal in dose 1 suppositoria at night during 15 days. It was established in majority cases that clinical symptoms and discharges have disappeared. The value of pH has decreased from 5.6-6.2 to 4.6-4.8. After biotherapeutic therapy significantly increased of the levels of Lactobacillus and percentage of the presence Bifidobacterium. The number of non-spore-forming obligatory anaerobic bacteria, Streptococcus and Gardnerella decreased in 10 and 100 times respectively.

10 Bifidobacterium strains and 10 Lactobacillus strains were studied for their antagonistic activity with respect to Escherichia coli, Klebsiella ozaenae, Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa and for their sensitivity to antibiotics, widely used in clinical practice. L. acidophilus strain 5/4, L. acidophilus strain 18/4, B. adolescentis strain UX, B. longum strain 44 exhibited the highest antagonistic activity and the highest degree of antibiotic resistance. The restriction analysis of the chromosomal DNA of these strains was then made and their plasmid content was studied, making it possible to recognize these strains in future in the course of in vivo experiments.

The antagonistic activity of 4 strains of bifidobacteria (B. adolescentis 2 F1, B. longum Z4, B. breve R2 and B. bifidum G1), isolated from the vagina of healthy females of the reproductive age, with respect to Escherichia coli, Klebsiella ozaenae, Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa and Gardnerella vaginalis were studied in vitro and in vivo. The in vitro experiments revealed that all above-mentioned bifidobacteria were capable of inhibiting the growth of all indicator bacterial strains. Still of all the bifidobacteria under study had different levels of activity. B. adolescentis strain 2 F1 exhibited the highest inhibiting activity in vitro. In contrast to in vitro experiments, in vivo experiments with B. breve R2 demonstrated its high antagonistic activity with respect to E. coli. The data thus obtained indicate that in the study of antagonistic activity the use of the in vivo model as also expedient, for it is mainly in vivo that probiotic preparations show their activity.

The composition of vaginal bifidoflora in 56 clinically healthy women of reproductive age was studied. The study revealed that four species of bifidobacteria, viz. Bifidobacterium bifidum, B. breve, B. adolescentis 2 and B. longum, dominated in the composition of this bifidobacterial population. Nine out of 11 isolated strains were found to be capable of inhibiting indicator microorganisms Staphylococcus aureus and Enterococcus faecalis when tested in vitro; in addition, strains B. adolescentis 2 F1, B. bifidum G1, B. breve P2 and B. longum Z4 inhibited Klebsiella ozaenae, Pseudomonas aeruginosa, Escherichia coli and were also active acid producers. Three of these 4 bifidobacterial strains were capable of adhesion to vaginal epitheliocytes, while B. bifidum G1 was practically incapable of adherence to these cells, similarly to B. bifidum strain 791 of intestinal origin. In addition, the spectra of antibiotic susceptibility varied from strain to strain, but all bifidobacterial strains were susceptible to benzylpenicillin and resistant to lomefloxacin, most of them being also resistant to cyprofloxacin and gentamicin. Thus the data presented in this work are indicative of the possibility and advantages of using bifidobacterial strains belonging to this ecological niche as probiotics for the correction of the microflora of the urogenital tract in females.

Inflammatory process in mandibular bone was induced in 39 outbred rats by a pure culture of Bacteroides fragilis and by an associative culture of B. fragilis and Staphylococcus aureus. Anaerobic microflora notably aggravated the course of inflammation. In contrast to inflammation in other parts of the skeleton, inflammation of the jaws involves a high risk of infection of the oral cavity by pathogenic microflora. A variety of microorganisms is isolated from the focus: from gram-positive staphylococci to gram-negative enterobacteria, which fact should be borne in mind when planning antibiotic therapy. Combined use of antibiotics active towards the entire spectrum of agents detected in this study is the most effective.

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 standardization of all components ensures the optimum experimental conditions; for this reason the obtaining and maintenance of animals meeting GLP requirements is one of the development of scientific research in biology and medicine. The aim of the present work was the study of the possibility of using gnotobiological technology for obtaining animals with different microbial status of the intestine and their maintenance. Our investigations revealed that obtaining animals with different microbial status of the intestine and their maintenance under the conditions of total gnotobiological isolation (TGBI) prevented the contamination of the animals, thus facilitating the standardization of research procedures. Gnotobiological technology made it possible to create the optimum maintenance conditions and to ensure constant microbial status in animals, free from pathogenic flora. The maintenance to totally decontaminated mice under TGBI conditions ensured the total germ-free status in these animals for 9 days.

The microbiological study of vaginal microflora in 40 patients of the reproductive age (20-30 years) with papilloma virus infection in association with cervical intraepithelial neoplasia of the uterine neck revealed dysbiotic disturbances in vaginal microflora, manifested by a decrease in the isolation rate and amount of lacto- and bifidobacteria and by excessive growth of opportunistic microorganisms. The 10-day course of corrective therapy with the new bacterial preparation "Zhlemik" was carried out. Group 1 (81 women) received the preparation intravaginally on a tampon, group 2 (19 patients) received the preparation in the form of vaginal suppositories. The results of this treatment were indicative of a high sanative effect of the preparation irrespective of the method of its application. This was demonstrated by the results of the bacteriological study made after bacterial correction: the amount of the Lactobacillus was restored, and they could be isolated from all patients; the level of contamination of the cervicovaginal niche with opportunistic microbial strains considerably decreased. The positive clinical effect after bacterial therapy with "Zhlemik" was observed in 93-95% of cases, depending on the form of its application.

The microbiological study of vaginal secretions of 39 female patients of reproductive age (20-30 years) with papilloma virus infection associated with cervical intraepithelial neoplasia (CIN) was carried out. Of these patients, 28 with papilloma virus infection associated with CINI-II made up group I and II having this infection associated with CINII made up group 2. Dysbiotic disturbances in vaginal bacterial flora, found in these patients, were manifested by a decrease in the isolation rate and number of the lacto- and bifidobacteria simultaneously with the excessive growth of opportunistic bacteria. The results of the oral administration of Solco-Trichovac are indicative of the effectiveness of this preparation, which was confirmed by the data of clinical and bacteriological studies. Together with an increase in the isolation rate of lacto- and bifidobacteria, the level of the contamination of the cervicovaginal niche with opportunistic and pathogenic bacterial strains decreased. The results thus obtained make it possible to recommend Solco-Trichovac for the complex treatment of with papilloma virus infection associated with CIN.

The results of our investigations revealed that in 68% of cases the treatment of patients with diffuse peritonitis with ampiox, gentamicin and metronidazole led to arresting the infectious process and to a considerable decrease in microbial contamination of the abdominal cavity. The use of cephalosporins and metronidazole proved to be effective in 85% of cases. In this treatment a considerable decrease in the amount of aerobic and anaerobic bacteria in peritoneal exudate was registered. In the process of treatment with cyprophloxacin positive clinical and microbiological dynamics were observed in all patients.

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.

These investigations revealed that the treatment of patients with generalized peritonitis with ampiox, gentamicin and metronidazole, as well as with cephalosporins and metronidazole, led to the aggravation of dysbiotic disturbances in normal intestinal microflora, observed in these patients before treatment. Ciprofloxacin had a selective decontaminating effect on the intestine, which facilitated the decrease of suppuration in postoperative wounds.

The impact of oral administration of heat-killed bifidobacteria, lactobacteria, enterococci and bacteroides on mouse resistance to experimental salmonellosis and content of immunoglobulin-synthesizing cells in the proper plate of the small intestine was studied. It was shown that the administration of the killed bifidobacteria, lactobacteria and enterococci increased the animal resistance to experimental salmonellosis infection and induced an increase in the content of immunoglobulin-synthesizing cells in the proper plate of the small intestine. The administration of the killed bacteroides had no such effect. Possible development of bacterial preparations with immunomodulating properties based on killed bifidobacteria, lactobacteria or enterococci is discussed.

Bacteriological study of intestinal microflora in test pilots, regularly exposed to excessive physical, as well as nervous and emotional strain, has revealed changes in the composition of their intestinal microflora. Correction of microflora by means of bifidumbacterin, a curative lactic fermentation alimentary product, was carried out. Rapid and effective restoration of intestinal microflora and improvement of the general state of patients were noted, which made it possible to recommend this product as a prophylactic remedy for subjects at risk of development of dysbiotic disturbances.

Comparative study of ciprofloxacin, pefloxacin and amikacin showed that ciprofloxacin and pefloxacin had a selective action on the intestinal microflora of conventional mice. Amikacin induced inhibition not only of the opportunistic bacteria but also of the representatives of the indigenous microflora. The use of the drugs in combination with total gnotobiological isolation in treatment of experimental radiation sickness provided an increase in survival of the irradiated animals, the more so as ciprofloxacin was used.

The possibility of stimulating the immunity of totally decontaminated mice, kept isolated under germ-free conditions, with the use of killed L. acidophilus Solco strains has been studied. As revealed in this study, the oral and intraperitoneal administration of strains O1 and O6 to mice leads to a significant increase in the content of immunoglobulin-synthesizing cells in the jejunal lamina propria of the animals. The oral administration of L. acidophilus Solco strain O6 and the intraperitoneal injection of L. acidophilus Solco strain O1 have been found to lead to a significant rise in the level of luminol-dependent chemiluminescence of mouse peritoneal macrophages. The total decontamination of mice induces the development of secondary immunodeficiency which influences the effectiveness of immunostimulating agents.

The state of enteric microbiocenosis in persons having contacts with different antimicrobial preparations, depending on the spectrum of such preparations and the duration of the contact, has been studied. Dysbiotic disturbances in enteric microflora have been detected even in those who have daily short-term contacts with antibacterial preparations.

In experiments on 406 CBA mice the effect of antimicrobial preparations, used in combination with total gnotobiotic isolation, on the survival rate of totally irradiated animals was studied. The use of antimicrobial preparations was shown to considerably enhance the survival rate of these animals. Cyprofloxacin, a new preparation of the kinolone row, exhibited a good effect ensuring selective decontamination of the intestine. The use of cyprofloxacin prior to irradiation with the subsequent isolation of the animals in gnotobiotic chambers increased the survival rate of these animals by 2.7 times. But the maximum survival rate of irradiated mice was observed in those cases when antimicrobial preparations were used both before and after irradiation in combination with the total gnotobiotic isolation of the animals.

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.

The study of the influence of cyprofloxacin on the microflora of the gastrointestinal tract has been made under experimental and clinical conditions. As revealed in this study, cyprofloxacin produces a corrective effect on the intestinal microflora; the action of this preparation, in contrast to that of other antimicrobial preparations, is retained for a long time. In patients having duodenal ulcer with bacteriosis caused by Campylobacter pylori and with intestinal dysbacteriosis the combination of cyprofloxacin and cimetidine yields a higher therapeutic effect than the use of cimetidine alone.

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.

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 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.

The effectiveness of a new bacterial preparation obtained from highly adhesive lactobacteria and intended for the correction of dysbiotic disturbances of vaginal microflora was studied in the treatment of 60 pregnant women with dysbacteriosis of the maternal passages. 30 pregnant women were simultaneously treated by the vaginal application of Lactobacterin. The study showed that the use of the preparation of highly adhesive lactobacteria caused the pronounced and stable correction of the microflora of the maternal passages. This correction was manifested by the domination of lactic acid bacterial flora and a decrease in the number of opportunistic microorganisms.