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The bactericidal and bacteriostatic properties (in darkness) of salts RE(NO3)3 · xH2O (RE = La, Ce, Gd, Yb, Y) and composite hydrogels with poly(N-vinylpyrrolidone) against Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Proteus mirabilis, and Klebsiella pneumonia bacteria and Candida albicans fungi have been analyzed. A correlation between the regions of delayed growth of microorganisms and the object characteristics is proposed. The mechanisms of interaction of Yb3+ ions of Yb(NO3)3 · xH2O salt, which exhibit high antimicrobial activity against Escherichia coli, Staphylococcus aureus, and Candida albicans with bacterial cell walls are demonstrated on ordered phospholipid monolayers (a model of biological membranes).

Composite nanoparticles with a core consisting of associated anatase crystallites and a polymeric shell consisting of poly(N-vinylpyrrolidone) or poly(N-vinylcaprolactam) were synthesized and found to have antimicrobial activity against Escherichia coli and Staphylococcus aureus as well as photocatalytic activity in decomposition of methyl orange and methylene blue dyes. The highest antibacterial activity of the particles with poly(N-vinylpyrrolidone) shell is due to the larger amount of S O 4 2 − groups and water adsorbed on the surface, while their photocatalytic activity is comparable with that of commercial nanoanatase samples.

Hydrolysis of TiOSO4 · xH2SO4 · yH2O and TiOSO4 · xH2O, performed in the presence of poly-N-vinylcaprolactam (PVCL) or poly-N-vinylpyrrolidone (PVP) and in an aqueous medium, has provided for the first time samples containing nanophases of, respectively, η-modification of TiO2 – x · nH2O ( intercalates TiO2 – x · (nH2O, PVCL) or TiO2 – x · (nH2O, PVP)) and with anatase structure (TiO2). The samples have been characterized by X-ray diffraction and X-ray photoelectron spectroscopy. They are found to have different antimicrobial activities. A relationship is established between the antimicrobial activity and the structural features of titanium(IV) oxide; concentration of hydrated titanium dioxide in the samples; and the content of free water and hydroxyl and $${\text{SO}}_{4}^{{2 - }}$$ groups on the surface of anatase and η-phase nanoparticles, respectively. The choice of polymer does not affect the antimicrobial activity.

The anatase nanoparticles are stabilized with titanium tetraisopropoxide Ti[OCH(CH3)2]4 and isopropyl alcohol without surfactants suitable for biological studies. We showed that the hydrodynamic radii in suspensions depend on temperature and the duration of hydrolysis, whereas the composition (a mixture of anatase with brookite, anatase, brookite, and rutile) and the sizes of crystallites (X-ray), nanoparticles, and aggregates (SEM) in the dried state are mainly dependent on the pH of the environment. The nonphase of the samples stems from coherent intergrowth of unit cells of anatase and brookite via geometric and structural complementarity. We found that photocatalytic activity (PCA; Rhodamine 6G model dye under UV radiation) depends on OH/H2O ratio (adsorbed), whereas antimicrobial activity (AMA) in the dark depends on an amount of free water on the surface of nanoparticles according to X-ray photoelectron spectroscopy (XPS). We revealed that samples with the smallest sizes of nanoparticles of all levels possess the highest PCA and AMA relative to Staphylococcus aureus and Escherichia coli.

The effect of γ-radiation on antimicrobial properties of gels based on polyvinylpyrrolidone was investigated. It was shown that the effects of [gamma]-radiation do not alter the antimicrobial activity of the antibiotics fosfomycin and gentamicin in the PVP matrix and that dioxidine loses its antimicrobial activity with increasing radiation dose. At low concentrations of the antibiotics, no synergistic effect from the simultaneous use of fosfomycin and gentamicin was observed; it started to develop only at a fosfomycin concentration of 5%.

The article presents the experience of successful complex treatment in a patient of high anesthetic risk with chronic postoperative sternum and ribs osteomyelitis developed after sternotomy for cardiac tamponade (perforation during radiofrequency ablation of the pulmonary veins mouths and cavotricuspidal isthmus) and retrosternal abscess associated with the presence of foreign bodies.

PVCL-intercalated samples containing nano-dimensional phases with η-modification of the TiO2−x·nH2O composition are obtained by hydrolysis of TiOSO4·xH2SO4·yH2O or TiOSO4·xH2O in the presence of poly(N-vinylcaprolactam) (PVCL). The incorporation of PVCL with water molecules into the interlayer space of the structure of the η-phase—TiO2−x·(PVCL nH2O)—is established by the X-ray diffraction study while the presence of PVCL in the sample composition is confirmed by the X-ray photoelectron and IR spectroscopy CHNS analysis and X-ray spectral microanalysis. Intercalated samples manifest the antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans. It is shown that the sample composition (the content of hydrated titanium dioxide) the composition of the η-phase (the presence of PVCL and H2O or the water content in the interlayer space of the structure), and the surface composition (S in the form of SO42− groups O in the form of adsorbed water and OH groups) affect the antimicrobial activity in the dark.

Impregnation composites and the conditions for fabricating them to make filled nonwoven materials with elevated physicomechanical properties were developed. The use of impregnation composites with a filler undergoing vibrational treatment in optimum conditions allows obtaining nonwovens with the ability to sorb heavy metal ions from aqueous solutions of surfactants and to selectively sorb microorganisms.

Ofloxacin susceptibility was tested with the use of 100 hospital isolates by the disk diffusion method vs. the activity of Oflomelid ointment tested by the cavity method. It was shown that the hospital isolates of all the species were susceptible to the Oflomelid ointment, while susceptibility to ofloxacin was preserved in S. epidermidis, the susceptibility of Acinetobacter spp., E. coli, Proteus spp. being intermediate. Such a difference in the susceptibility of the isolates was evidently due to the properties of polyethylene glycols in the ointment composition.

The comprehensive morphological investigation indicated a high antimicrobial activity of iodine-containing ointments in the treatment of septic wounds from the first days of the ointments using. 3% ointment "Stellanin-PEG" helps to reduce the local inflammatory changes by activating neutrophils and macrophages. A management of wounds by 3% ointment "Stellanin-PEG" improves their condition by stimulating regeneration, which leads to an intensification of the proliferative and functional activity of granulation tissue. Clinical, morphological and cytological data are evidence of time reduction of relief of purulent process, which leads to an earlier (in comparison with the use of ointment "Betadine") wound epithelization.

Rapid testing of pathogen susceptibility to antibiotics is of great practical value for rational chemotherapy of pyoinflammatory deseases and postoperative complications of microbial etiology. The standard microbiological methods, i.e., the disk diffusion method and the method of serial dilutions are labour- and time-consuming (not less than 18-36 hours). The method of the authors is based on measuring bioluminescence resulting from interaction of adenosine-5'-triphosphate (ATP) and ATP reagent, a standard reaction mixture of firefly luciferase (an enzyme) and luciferin. The bioluminescence intensity is proportional to the ATP concentration in the reaction mixture and the ATP concentration is proportional to the number of the pathogen viable cells in the sample. The bioluminescence intensity value in the pathogen suspension aliquots with and without (control) the antibiotic were compared after the incubation for 5 hours and the coefficient of the microbial cell growth inhibition was calculated. Satisfactory correlation (R288%) of the results of the bioluminescent assay and the assay with the disk diffusion method and the method of serial dilutions was observed.

Comparative antimicrobial activity of four ointments, i. e. stellanin-PEG, levomecole, dioxydin 5% ointment and betadin was studied with the use of collection microbial strains and the most frequent pathogens of pyoinflammary processes in surgical patients. Clinical strains of gram positive and gram negative organisms were used as the test cultures. Stellanin-PEG 3% ointment showed high antimicrobial activity against both the gram positive and the gram negative organisms, including methicillin resistant staphylococci, E. faecalis, E. faecium, as well as E. coli and Klebsiella spp. producing extended spectrum beta-lactamases. As a whole, stellanin-PEG 5% ointment was inferior only to 5% dioxydin ointment.

Severe hypercoagulation syndrome was diagnosed in patients with various forms of diabetic foot. Pathology at coagulogram parameters reflects systemic metabolic and inflammatory disturbances. Anticoagulant therapy should be combined with correction of glycemia, treatment of infection and critical ischemia. Only this complex therapy can normalize coagulation parameters and reduce the risk of thrombotic complications.

Clinical and microbiological efficacies of a combined drug, a fixed combination of ciprofloxacin and tinidazole in the form of tablets (Cifran ST, Ranbaxy, India) were studied. The drug was given to 40 patients with skin and soft tissue infections in the complex surgical treatment. The clinical effect and bacteriological efficacy were observed in 97.5 and 75% of the cases respectively. The drug tolerability was good and no adverse reactions were stated.

Anaerobic infection is one of the most complicated problems of pyosurgery. The algorithm of examination of patients with anaerobic infection including intraoperative diagnosis is proposed. Surgical treatment playing also diagnostic role is the basis of combined treatment of soft tissues anaerobic infection. Early diagnosis and active surgical policy is one of the main ways of problem solving.

Three hundred and fifteen patients with necrotic forms of diabetic foot were examined and treated. Neuropathic infected form of diabetic foot was diagnosed in 45.7% patients, neuro-ischemic form--in 54.3%. Mixed aerobic-anaerobic infection in foot's necrotic focus was detected in 87.6% diabetic patients, only aerobic--in 12.4%. High level of intoxication was seen in these patients. Algorithm of complex surgical treatment of different forms of diabetic foot is presented.

The in vitro study of the influence of photodynamic action (with the use of photosensitizer "Photosens", laser and non-laser irradiation) on the strains of the main representatives purulent wound microflora was carried out. Staphylococcus aureus, S. epidermidis, Pseudomonas aeruginosa, Escherichia coli, Proteus mirabilis cultures have been isolated from wound secretions and identified. The photosensitizer was shown to produce no bactericidal effect by itself. Irradiation with laser and non-laser light sources induced a sharp decrease in the number of viable cells in the cultures under study. The irradiation of the photosensitizer led to its activation, manifested in bactericidal action. The results thus obtained confirm good prospect of using photodynamic therapy for the treatment of purulent wounds.

To evaluate effectiveness of sulodexide in patients with pyonecrotic complications of diabetic foot.Sulodexide was given to 15 patients which were examined for blood fibrinogen, foot tissues saturation with oxygen, microbic contamination of the wound tissue. In addition, ultrasound dopplerography of foot arteries, laser doppler flowmetry were performed.Fibrinogen in peripheral blood fell, arteriovenous shunting diminished, capillary blood flow and oxygen saturation of the tissues improved.Even early sulodexide treatment is effective at different stages of the pathological process in diabetic patients with severe pyonecrotic lesion of the lower limbs as it recovers microcirculatory blood flow.

For the period from 1996 to 1998 in the Division of wounds and wound infection of A.V. Vishnevsky Institute of Surgery 92 patients with pyonecrotic forms of "diabetic foot" underwent thorough examination and treatment. The patients were divided into groups by the form of "diabetic foot": with pyonecrotic forms of "diabetic foot" without critical ischemia (group 1) and with it (group 2). In 18 patients of both groups the data of electron autoradiography were used to reveal peculiarities of the wound process. Group 1 patients had at admittance a large number of neutrophiles in various stages of destruction in biopsies of the wound. In patients of group 2 a great majority of the vessels in biopsies of the wound were in different stages of destruction with lost connections between their separate cells or some of their part absent. Separate cells (endotheliocytes and pericytes) which make up the walls of destroying vessels, were synthesizing RNA and were functionally active. In both groups, the studied parts of the wound before plastic repair of its defect usually represented as well developed granulation tissues with a number of microvessels and cells. Intensive synthesis of PNA in the cells of microvascular wall evidenced of their high functional activity, and the synthesis of DNA in them showed their ability for proliferation, i.g.--for growth. Thus, microangiopathy was reversible, and the solution of the problem of critical ischemia should be considered in the light of macroangiopathy. Thus, in patients of group 1 the cause of pyonecrotic damage consists in infection process, while in patients of group 2--in combination of infection with ischemia of the extremity. In both groups pyonecrotic disease of the extremity ruses at the background of severe disturbances of cellular immunity.

The analysis of the treatment of 900 patients with large festered wounds of various genesis and location for the period from 1973 to 1998 years in the intensive care department has shown, that infection of respiratory ways is encountered in 30% of cases (in patients with nonsporeforming anaerobic bacteria--in 11-12%), bacteriuria--in 70-80%, bacteriamia--in 75% of patients with sepsis. In acute pyogenous diseases of soft tissues microbes from the wounds in monoculture were isolated out in 83.3% of cases, associations of gram-positive and gram-negative bacteria--in 16.7%, in chronic pyogenous diseases of soft tissues--in 60 and 40% of cases, respectively. In sepsis associations of gram-positive and gram-negative microbes were isolated in 55.6% of cases. Most often (91%) pathogenic staphylococcus was found in hemocultures. Uring in 62% of cases contained association of gram-positive and gram-negative microorganisms, in sputum gram-positive microflora in monoculture (69%) prevailed. In the group of patients with peritonitis, phlegmon of the anterior abdominal wall, diabetic phlegmon and gangrene, crush syndrome the association of anaerobic and aerobic microflora (from 57.1 to 98.8%) prevailed in the wounds. Application of up-to-date antimicrobial means in the intensive care unit resulted in a decrease of mortality rate in sepsis and complicated course of wound infection up to 23%, and in anaerobic nonsporeforming infection--up to 15%.

Piperacillin/tazobactam (P/T) or tazocin was used in the treatment of 40 patients with soft tissue purulent necrotic wounds of various genesis and localization. In the majority of the patients the affection was of recurring nature. P/T was administered in a dose of 4.5 g 3 times a day for 1 to 14 days (mainly for 8 to 10 days) as 30-minute intravenous infusions. The clinical effect of the treatment was stated in 36 patients (90 per cent). In 3 out of 8 patients with diabetes mellitus the treatment failed. In 1 patient the treatment was discontinued after the first dose because of asphyxia and a short-term decrease of the arterial pressure. Among 105 microbial strains isolated from 75 patients 64 were highly susceptible to P/T, 33 were moderately susceptible and 8 were resistant. 76.3 per cent of the isolates produced beta-lactamase, 66.3 per cent of them were susceptible to P/T. 54 gram-positive and gram-negative strains were isolated from 40 patients. 16 out of the 54 strains were isolated as monocultures and the others as associations. After the treatments the pathogen eradication and the pathogen eradication followed by superinfection were stated in 26 patients (66.7 per cent). In 11 patients (28.2 per cent) the pathogen persistence was observed at the background of the clinical improvement in the majority of the patients. The relapses were recorded in 2 patients (5.1 per cent).

It was established in animal experiments that in generalization of purulent infection, the most probable sources of the increased blood serum tryptophan content, determined by the fluorescence method, are the muscles, lungs, and, to a lesser measure, the liver, which are invaded by P. aeruginosa and St. aureus. The increase of the level of tryptophan fluorescence in blood serum, which is encountered in generalization of purulent infection, does not correlate with the level of cortisol, insulin, and proteolytic activity in the blood; it also does not occur in pyrogenal-induced fever.

The protective activity of pyoimmunogen II, lot 9, was studied on P. aeruginosa experimental sepsis used as a model. In experiments on rats the preparation was shown to be nontoxic according to the results of the determination of acute and chronic toxicity. The preparation under test produced a high protective effect in experiments on animals infected with various P. aeruginosa strains, irrespective of their virulence and immunotype. Anti-P. aeruginosa plasma, obtained by plasmapheresis from donors immunized with pyoimmunogen II, showed a curative effect when injected into experimental animals in a dose of 0.02 ml/g body weight at early stages of the infection.