Preparation of Type II Collagen Short Peptides: Temperature Conditions of Cartilage Homogenization and Collagen Hydrolysis.

Physicochemical properties of hyaline cartilage homogenates were studied by the method of microcalorimetry. Collagen hydrolysates were obtained after homogenization of hyaline cartilages under high pressure conditions at the temperatures that denaturate collagen. Thermodynamic parameters of thermal transition of collagen in cartilage suspension were determined. Enthalpy of thermal transition ΔН decreases in comparison with the control. Thermal transition half-width ΔТ varies with temperature. More denatured and homogeneous samples were obtained at homogenization temperature 80°C. According to spectral studies, particles in the samples obtained at the temperature of 80°C were smaller. The temperature of 80°C is preferred for homogenizing hyaline cartilages and obtaining collagen type II short peptides.

[DIAGNOSTIC AND THERAPEUTIC BRONCHOSCOPY IN PATIENTS UNDERGOING CARDIAC SURGERY IN INTRA- AND POSTOPERATIVE PERIODS].

The article presents research conducted to evaluate the use of diagnostic and therapeutic fiberoptic bronchoscopy in the treatment of ventilator-associated pneumonia (VAP) and tracheobronchitis in patients in cardiac ICU. The paper presents the results of the study and comparison of invasive techniques for sampling from the respiratory tract for bacteriological analysis. We studied the bacterial profile of ICU, original content of the respiratory tract of cardiac patients in the intraoperative period and possible ways for prevention of VAP and tracheobronchitis in the postoperative period using bronchoscopy. In addition data on the effect of bronchoscopy on the respiratory and cardiovascular systems in cardiac surgical patients undergoing mechanical ventilation presented.

[THE ROLE OF MICROBIOLOGICAL MONITORING AND DRUG HISTORY IN THE EFFECTIVENESS OF ANTIBIOTIC PROPHYLAXIS AND ANTIBIOTIC TREATMENT OF INFECTIOUS COMPLICATIONS AFTER RECONSTRUCTIVE SURGERIES].

MATERIAL AND METHODS: We analyzed the results of the local microbiological monitoring carried out in 2010-2013. The monitoring included the study of biological material of patients with clinical signs of infectious and inflammatory complications after reconstructive surgery. We studied the dynamics of the isolation of major pathogens (Staphylococcus spp., Enterococcus spp., representatives of Enterobacteriaceae, Pseudomonas aeruginosa, Acinetobacter baumannii, Candida spp.) and their sensitivity to major antibiotics. RESULTS: We demonstrated the role of local monitoring and knowledge of the "drug history" in achieving of effective starting empirical antibiotic therapy.

[Clinical and bacteriological characteristic of infectious purulent complications in patients after related renal transplantation].

We investigated the frequency and characteristics of infectious purulent and non-infectious complications in living related renal transplant recipients in early postoperative period. It was identified the prevalent microorganisms in urinary tract infections and its antibiotic sensitivity: Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae, Citrobacter freundii, Staphylococcus epidermidis, Enterococcus faecalis, Candida albicans. 182 strains of bacteria and Candida were isolated from urine of renal graft patients in early postoperative period (from 2 days to 3 months). The prevention and treatment schemes, antimicrobial drugs dosing regimen were developed. It leads to decrease the infectious complications rate.

[Problem of treatment for pyo-inflammatory complications caused by Acinetobacter].

The article deals with analysis of a detection frequency and antibacterial treatment resistance of Acinetobacter spp.of different species affiliation. Strains of bacteria detected in patients with pyo-inflammatory complications after surgeries (period from 2010 to 2012) were involved in the study 137 strains of Acinetobacter spp. were detected and studied Fraction of Acinetobacter spp. in 2010, 2011 and 2012 was 2.3, 3 and 3.4% respectively. Fraction of P. aeruginosain all non-fermentative Gram-negative bacteria (NFGNB) decreased by 120% and fraction of Acinetobacter spp. increased by 200-250%. Acinetobacter spp. detection frequency was not significantly changed in the period from 2006 to 2012. However the fraction of Acinetobacter spp. in NFGNB increased by 150% and was 29% in 2012. Detection frequency of A. baumanii sharply increased in 2012. A study of antibacterial treatment resistance of Acinetobacter spp. (10 antibacterial medicines) showed that Polymyxin B and E (Colistin) was the most effective medicine for A. baumanii and A. calcoaceticus infection. 85-95% of Acinetobacter spp.strains kept sensitivity to this antibacterial medicine. 66-88.9% of A. baumanii strains, 66.7-81.8% of A. alcoaceticus and 66.6% of other Acinetobacter spp. were sensitive to Tigecycline. Dioxidine effectiveness was close to Tigecycline in 66.7-80% of A. baumanii strains. 85-100% of A. calcoaceticus strains were sensitive to Dioxidine. There is a trend of decreasing of A. baumanii sensitivity to Carbapenems by 200%. Fraction of strains sensitive to Meropenem and Imipenem in 2012 was 21.4% and 16.7% respectively. All studied strains of A. lwoffi and A. haemolyticus kept sensitivity to Carbapenems. In 2012 23.8% of A. baumanii and 50% of A. calcoaceticus strains were sensitivity to Amikacin, meanwhile A. lwoffi and A. haemolyticus were not sensitive to this medicine. 31.3% of A. baumanii and 50% of A. calcoaceticus strains were sensitive to Ceftazidime/Sulbactam. 5.3% of A. baumanii and 15.8% of A. calcoaceticus strains were sensitive to Piperacillin/Sulbactam. Gentamicin effectiveness was fixed in 12.5% of A. baumanii and 45.5% of unidentified Acinetobacter-strains. Gentamicin was not effective against A. lwoffii and A. haemolyticus. Thus Polymyxins (in monotherapy or in combination with glycopeptides), Dioxidine and Tigecycline in combination with Carbapenems or Cefiazidime/Sulbactam are to be drugs of choice in treatment for pyo-inflammatory complications caused by Acinetobacter spp.

[Comparative analysis of associations of polymorphic genes F2, F5, GP1BA and ACE with the risk of stroke development in Russian and Ukrainian populations].

The comparative analysis of the associations between G20210A polymorphism of F2 gene, G1691A polymorphism of F5 gene, -5T/C polymorphism of gene GP1BA, I/D polymorphism of gene ACE and the risk of development of the stroke in two ethnical samplings--Russian and Ukrainian populations--was conducted. It was shown that the patients of the Russian population with genotype DD have a higher level of the risk of ischemic stroke development (OR = 1.4, 95% CI [1.05; 1.78], p = 0.02), whereas genotypes I/I and I/D are associated with the lower level of risk of ischemic stroke (OR = 0.7, 95% CI [0.56; 0.95], p = 0.02). In the Ukrainian ethnical sampling, differences in distribution of genotypes and alleles frequencies between patients with stroke and healthy persons upon given polymorphic locus are not significant, and I/D polymorphism of gene ACE is not associated with the risk of development of the stroke (OR = 0.8, 95% CI [0.48; 1.32], p = 0.45). The G20210A polymorphism of gene F2, G1691A polymorphism of gene F5, -5T/C polymorphism of gene GP1BA are not associated with the risk of stroke in two ethnical samplings.

[Study of membranotropic and antioxidant activity of flavonoids and their complexes with ferric iron].

We studied the interaction with liposomes and the antioxidant activity of flavonoid (quercetin, catechin, taxifolin) complexes with iron (III). It was found that the lipophilicity of complexes depends on an iron:flavonoid ratio and grows at a ratio of 1 to 1, while complexes in a 2:1 ratio were the most effective to slow down the lipid peroxidation and restore radical 2,2-diphenyl-1-pic: rylhydrazyl. Thus, the stoichiometry of complexes formed in aqueous solution, may differ from the stoichiometry of complexes that most effectively protect membranes from.peroxidation.

[Microbiological monitoring in therapy of patients with iatrogenic esophageotracheal fistula].

The results of the microbiological diagnosis of infective inflammatory complications in patients with iatrogenic esophageotracheal fistula and the tactics of their antibacterial prophylaxis and therapy within a 9-year observation period (2003-2011) were analysed. The main organisms colonizing the tracheobronchial tree in the patients were S. epidermidis, S. aureus, enteric bacteria, P. aeruginosa and Candida. An increase of the S. epidermidis resistance to rifampicin, moxifloxacin and especially ciprofloxacin was observed. The resistance of S. aureus did not significantly change. Within the observation period, high susceptibility of all the Staphylococcus isolates to vancomycin and linezolid remained stable. Among the nonfermenting gramnegative bacteria, the P. aeruginosa isolates were the most frequent and characterized by a lower portion of the isolates with preserved susceptibility to the agents (except polymyxin B) known earlier as antipyocyanic antibiotics, i.e. to imipenem and cefepim. Since the proportion of P. aeruginosa in the etiology of pyoinflammatory processes in the region of esophageotracheal fistula ranged within 9.3 to 17.5%, the fact should be considered in the antibiotic therapy. There was observed an increase in the frequency of infectious complications due to other nonfermenting gramnegative bacteria (acinetobacters) and first of all A.baumannii. Various Candida isolates were characterized by dependence of the susceptibility on the selective pressure of irrational therapy, as well as their species (the presence of such species as C. Krusei and C. glabrata with natural resistance), that required not only the species identification but also determination of the Candida isolates resistance in every particular case.

[Collagen fibril formation in vitro at temperatures close to physiological values].

Fibril formation of collagen from porcine skin was studied at temperatures of 28-39 degrees C. Collagen fibrils obtained in this temperature range have the different degree of order. An optimal temperature for the formation of collagen fibrils is found to be 36.5 degrees C; the structure of fibrils formed at this temperature is more homogeneous than that formed at 34.5 degrees C and 38.5 degrees C. As indicated by electron microscopy data, fibrils with a minimal diameter are formed at physiological values of pH, ionic strength, and temperature. The greater diameter of fibrils formed at 34.5 degrees C is due to a high level of hydration of collagen molecules. Fibril diameter is larger at 38.5 degrees C owing to the cooperative unfolding of the triple helix and a weakening of the binding of collagen molecules.

Interference phenomena and long-range proximity effect in clean superconductor-ferromagnet systems.

We study peculiarities of the proximity effect in clean superconductor-ferromagnet structures caused by either the spatial or momentum dependence of the exchange field. Even a small modulation of the exchange field along the quasiparticle trajectories is shown to provide a long-range contribution to the supercurrent due to the specific interference of particle- and holelike wave functions. The momentum dependence of the exchange field caused by the spin-orbit interaction results in long-range superconducting correlations even in the absence of a ferromagnetic domain structure and can explain recent experiments on ferromagnetic nanowires.

[Antibiotic resistance dynamics and isolation rate of staphylococci and enterococci from patients of reconstructive surgery units].

The dynamics of isolation of staphylococci and enterococci from clinical material of patients and their antibiotic susceptibility within a 5-year period (2005-2009) was analysed. 5990 isolates were tested: 1250 isolates of Staphylococcus aureus, 3268 isolates of S. epidermidis, 1005 isolates of Enterococcus faecalis and 467 isolates of E. faecium. Grampositive infections were shown to be prevailing within the last 2-3 years, the nosocomial epidermal staphylococci more and more replacing S. aureus (the ratio of S. epidermidis and S. aureus in 2009 was 3.3). The isolation rate of E. faecalis significantly increased (by 3.5 times) and the ratio of E. faecalis and E. faecium in 2009 was 4.3. The microflora composition with respect to the isolation source was analysed and its clinical significance was estimated. The study of the antibiotic susceptibility showed that oxacillin had its own specific niche, while antibiotics active against resistant grampositive cocci, such as rifampicin, fusidic acid, fluoroquinolones (moxifloxacin), cefoxitin, as well as amoxicillin/clavulane in infections due to E. faecalis, might be considered as the drugs of choice. In the treatment of nosocomial infections, when the etiological role of MRSA or VRE is suspected or confirmed, the complex therapy should obligatory include the most active antibiotics (vancomycin or linezolid among them).

[Interaction of protein with charged colloidal particles].

The functional state of three proteins of different molecular weight (urease, lactate dehydrogenase, and hemoglobin) in the presence of the linear polyelectrolytes poly(allylamine hydrochloride) (PAA) and sodium poly(styrenesulfonate) (PSS) in the dissolved state and of the same polyelectrolytes bound to the surface of microspheres has been investigated. Microspheres were prepared by consecutive absorption of oppositely charged polyelectrolytes so that the outer layer of the shell was PAA for the acidic protein urease, and PSS for the alkaline proteins LDH and hemoglobin. It was shown that the dissolved polyelectrolyte completely inactivates all three proteins within one minute with a slight difference in the time constant. (By Hb inactivation are conventionally meant changes in the heme environment observed from the spectrum in the Soret band.) In the presence of microspheres, the proteins were adsorbed on their surface; in this case, more than 95% of the activity was retained within two hours. The proportion of the protein adsorbed on microspheres accounted for about 98% for urease, 72% for Hb, and 35% for LDH, as determined from the tryptophan fluorescence data. The interaction of hemoglobin with another type of charged colloidal particles, phospholipid vesicles, leads to the destruction of the tertiary structure of the protein, which made itself evident in the optical absorption spectra in the Soret band, as well as the spectra of tryptophan fluorescence and circular dichroism. In this case, according to circular dichroism, the percentage of alpha-helical structure of Hb was maintained. The differences in the physical and chemical mechanisms of interaction of proteins with these two types of charged colloidal particles that leads to differences in the degree of denaturing effects are discussed.

Immune response during activation of pre- and postsynaptic serotonin 5-HT(1A) receptors in C57Bl/6J mice at various stages of a depression-like state.

The development of a depression-like state in C57Bl/6J mice with repeated defeat experience (10 and 20 days) was accompanied by inhibition of the immune response (evaluated from the number of IgM antibody-producing cells). Activation of postsynaptic 5-HT(1A) receptors with a selective agonist 8-OH-DPAT (1.0 mg/kg) in these animals had no effect on the immune reaction. In mice without the experience of confrontations, stimulation of postsynaptic receptors caused a decrease in the number of IgM antibody-producing cells at the peak of the immune response induced by sheep erythrocytes (5×10(8) cells). However, the count of these cells remained unchanged in mice with a depression-like state (irrespective of the stage of disorder). Activation of presynaptic 5-HT(1A) receptors with 8-OH-DPAT (0.1 mg/kg) in control animals and mice with 10-day defeat experience was followed by immune stimulation. These changes were not observed in mice with a depression-like state caused by 20-day social stress.

[Thermal stability of lactate dehydrogenase in the complex with the anion polyelectrolyte poly(styrene sulfonate)].

The temperature stability of the cytoplasmic enzyme of the glycolysis of lactate dehydrogenase from a pig muscle (isoenzyme M4) in a complex with the anion polyelectrolyte poly(styrenesulfonate) has been investigated by the methods of adiabatic differential scanning microcalorimetry, the own protein fluorescence, and circular dichroism. Calorimetric investigations of complex of lactate dehydrogenase with poly(styrenesulphonate) in 50 mM phosphate buffer at pH 7.0 have shown that the temperature of the transition and enthalpy of lactate dehydrogenase thermal denaturation sharply decreases with growing weight ratio poly(styrenesulphonate)/lactate dehydrogenase, though at 20 degrees C the enzyme activity of lactate dehydrogenase remains unchanged for several hours irrespective of the addition of poly(styrenesulphonate). The addition of phosphate ions to the solution enhances the resistance of lactate dehydrogenase to both thermal denaturation and inactivation by polyelectrolyte. The data obtained are interpreted from the viewpoint of a special role of two anion-binding centers in intersubunits contacts of lactate dehydrogenase, which enhance its resistance to both thermal denaturation and destruction by polyelectrolyte.

[Nonfermentative gram-negative bacteria: isolation rates and antibiotic sensitivity].

The isolation rates of nonfermentative gram-negative bacteria (NFGNB) are analyzed in the inpatients treated at the B. V. Petrovsky Russian Surgery Research Center in 2005-2009 and antibiotic resistance trends in nosocomial strains of NFGNB are traced in the above period. The study of the etiological structure of nosocomial infections has shown that the past 2 years (2008 and 2009) were marked by a clear tendency for the preponderance of gram-positive coccal pathogens (46.8 and 53.9%) with a considerable (1.5-2-fold) reduction in the proportion of representatives of enterobacteria (31.5 and 24.5%) and NFGB (13.4 and 11.3%), but with an increase in the proportion of fungi up to 7.1 and 8.6%, respectively. Among the NFGNBs, P. aeruginosa remains ohe of the most common pathogens for nosocomial infections although its portion in the number of all etiologically significant microorganisms was substantially reduced (from 13% in 2005 to 4.6% in 2009). It continues to remain one of the most common causative agents for infections of the urinary tract (e.g., after renal transplantation) and upper and lower respiratory tract (e.g. nosocomial pneumonia) and for those developing after surgical interventions (postoperative wound suppuration discharged along the drainages, from a T-sized tube, etc.). Among the NFGNBs, Acinetobacter spp. was the second frequently isolated pathogen, the isolation rate for which also decreased from 7.9% in 2005 to 2.6% in 2009. Polymyxin B and carbapenems (imipenem, meropenem, and doripenem) showed the highest activity against the vast majority of the test strains; however, there was an absolutely clear declining trend in the proportion of carbapenem-sensitive strains among virtually all the NFGNBs under study. According to the proportion of imipenem-, meropenem-, and doripenem-sensitive nosocomial P. aeroginosa strains (66.7, 46.6, and 44.7%, respectively), doripenem had the least activity. Acinetobacter spp. strains sensitive to these drugs showed the same trend (85.1, 51.2, and 39.2%, respectively). Meropenem and doripenem were equally active against B. cepacia strains, each demonstrated 50% sensitivity. As compared with meropenem, doripenem had a preferential activity against only O. anthropi (75 and 57.1% sensitivity, respectively). All the three carbapenems were inactive against S. maltophilia.

[Dynamics of acquires resistance in the main gramnegative pathogens of surgical infections to beta-lactams in 2004-2008].

Resistance of 2134 clinical isolates of etiologically significant species of gramnegative bacteria to 5 beta-lactam antibiotics, i. e. cefepime, piperacillin/tazobactam, cefoperazone/sulbactam, imipenem and ceftazidime (the 3rd generation cephalosporin) as the reference drug was investigated for the period of 5 years (2004-2008). In total, 554 strains of E. coli, 578 strains of P. aeruginosa, 255 strains of Acinetobacter spp., 161 strains of Proteus mirabilis, 359 strains of Klebsiella pneumoniae and 227 strains of Enterobacter cloacae were assayed in dynamics. The comparative analysis of the frequency of the antibiotic resistant isolates from the patients treated within 2004-2008 with often and long-term use of cefoperazom-sulbactam, meropenem and imipenem revealed an increase in development of resistance to all beta-lactams, including the inhibitor-protected ones. It least of all concerned imipenem, still isolation of 39.5% of the imipenem resistant strains of P. aeruginosa was in favour of the tendency. A dramatic 3-5-fold rise of resistance in 2007 and 2008 in the isolates of K. pneumoniae, E. cloacae and Acinetobacter spp. to both the inhibitor-protected beta-lactams, that averaged 56 and 45%, 45 and 35% and 26 and 30% respectively, deserved attention. It was assumed that the main mechanism of resistance in the isolates to the inhibitor-protected beta-lactams was hyperproduction of beta-lactamase of type CTX-M. The large part of the cefepime resistant isolates of K. pneumoniae and Acinetobacter spp. (76.8 and 62.2% respectively) was in favour of the assumption. It was concluded that periodical reversion of the policy of preventive antibiotic prophylaxis was necessary, since such a prophylaxis is a reliable barrier to development of postoperative complications and at the same time it promotes selection of nosocomial strains with some other mechanisms of antibiotic resistance under hospital conditions.

[Immune response under activation of pre- and postsynaptic serotonin 5-HT1A-receptors in mice with depressive-like behavior].

Development of depressive-like state in mice of the C57BL/6J strain is accompanied by a considerable decrease in the immune response. A selective activation of presynaptic 5-HT1A-receptors (8-OH-DPAT, 0.1 mg/kg, for 15 min before immunization) markedly increased the immune response tested with the number of IgM-antibody-forming cells, and stimulation of postsynaptic 5-HT1A-receptors (8-OH-DPAT, 1.0 mg/kg, for 30 min before immunization twice) produced an immune suppression in control animals (mice without experience of victories and defeats). On the other hand, there were no changes in the immune response level following 8-OH-DPAT administration (0.1 and 1.0 mg/kg) in mice with depressive-like state. The role of pre- and postsynaptic 5-HT1A-receptors in immunomidulation in mice with depressive-like behaviour is discussed.

[Infectious complications in patients with iatrogenic diseases of the trachea and esophagus].

Methods for microbiological monitoring could analyze the microflora isolated in 372 patients with iatrogenic diseases of the trachea and esophagus, who were treated at the Department for Surgery of the Lung and Mediastinum, Acad. B. V. Petrovsky Russian Research Center of Surgery, Russian Academy of Medical Sciences, in 2003 to 2009. Major groups of microorganisms colonizing the tracheobronchial tree in patients who had undergone long-term resuscitation, injuries, surgery, etc. and in those who had admitted to the department from other clinics are identified. The main clinically significant microorganisms isolated during the pathological process in this area were Staphylococcus epidermadis (3.9-13.3%), St. aureus (12.4-21.1%), Pseudomonas eruginosa (9.2-17.5%), and Candida fungi (7.8-12.2%). This indicates the greater importance of the fungal microflora and its representatives' resistance to the most commonly used drugs. Rational antibacterial therapy regimens are proposed in relation to the type of microorganisms colonizing the tracheobronchial tree.

[Does collagen microunfolding stimulate the fibril formation?].

The data on the effect of temperature on the kinetics of collagen fibril formation at physiological pH values and ionic strength in the temperature range 26-39 degrees C have been analyzed. The temperature of 35 degrees C optimal for collagen fibril formation has been defined as the turning point for halfmaximal turbidity and collagen molecule microunfolding values, which corresponds to the temperature of the first transition on the heat absorption curve. The temperature range (32-35 degrees C) in which collagen microunfolding stimulates fibril formation has been determined.

[Interaction of taxifolin (dihydroquercetin) with dimyristoylphosphatidylcholine multilamellar liposomes].

Differential scanning calorimetry was used to study the influence of the flavonoid taxifolin (dihydroquercetin) on the temperature-dependent phase transition of dimyristoylphosphatidylcholine multilamellar liposomes. Taxifolin was added to organic solution of the lipid during the procedure of liposomes preparation (addition from-within) or to a suspension of prepared liposomes (addition from-without). In the first case, liposomes contained from 2 to 50 mol% of taxifolin added from-within; in the second case, lyposomes were treated with 0.001% or 0.01% taxifolin. In both cases, the effect was similar. When the concentration of taxifolin increased, the temperature of lipid melting decreased while the width of transition considerably enlarged. Freeze-fracture electron microscopy revealed that taxifolin did not rupture multilamellar liposomes, while the formation of ripple-phase was retarded in all bilayers even when the liposomes were treated from without. This suggested the ability of taxifolin to penetrate through numerous bilayers of multilamellar liposomes.