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Aim: to determine main risk factors for complications of ureterolithotripsy., Materials and Methods: a retrospective analysis of the results of 545 ureteroscopies performed in 506 patients with ureteral stones over the past 7 years at the urological clinic named after M.F. Vladimirsky was carried out. The relationship between preoperative and intraoperative factors and complications of ureterolithotripsy was analyzed., Results: The overall complication rate was 22.4%. The risk of intraoperative complications was proved to increase (p<0.05) along with the stone size, location in proximal ureter, stone impaction for more than 3 weeks and the degree of hydronephrosis. No preoperative stenting or nephrostomy tube prior to ureteroscopy was associated to an increased risk of intraoperative complications (RR=2.88; p=0.03). Patients with preoperative drainage of upper urinary tract has lower probability of intraoperative complications (OR=0.35; p=0.03). The risk of developing stricture and ureteral obliteration in uncomplicated ureteroscopy was minimal (RR=0.008, p=0.0001). Small ureteral perforation and pronounced mucosal inflammation around the stone have the similar influence on the risk of complications, which was more than 7.5 times (p=0.0001) higher than in uncomplicated ureteroscopy. Large ureteral perforation was associated with the highest risk of stricture formation and ureteral obliteration, which was 64 times (p=0.0001) higher than in uncomplicated ureteroscopy., Conclusion: The rate of complications of ureterolithotripsy directly depends on the following factors: size and location of the stone, the stone impaction, pre- and intraoperative (nephrostomy tube) drainage of the upper urinary tract, the degree of hydronephrosis, level of bacteriuria and intraoperative trauma complications.

Thin macroporous poly(vinyl alcohol) (PVA) hydrogels were produced by cross-linking of PVA in a semi-frozen state with glutaraldehyde (GA) on glass slides or in the wells of microtiter plates. The 100-130 μm-thick gels were mechanically transferable, squamous translucent films with a high porosity of 7.2 ± 0.3 mL/g dry PVA i.e. similar to larger cylindrical PVA monoliths of the same composition. Additional treatment of the gels with 1% GA increased the aldehyde group content from 0.7 to 2.4 μmol/mL as estimated using dinitrophenylhydrazine (DNPH) reagent. Translucency of the gels allowed registration of UV-visible spectra of the DNPH-stained films. The catalytic activity of trypsin covalently immobilized on thin gels in the microtiter plates was estimated with chromogenic substrate directly in the wells, and indicated that the amount of protein immobilized was at least 0.34 mg/mL gel. Human immunoglobulin G (IgG) immobilized on thin gels at 0.1-10 mg/mL starting concentrations could be detected in a concentration-dependent manner due to recognition by anti-human rabbit IgG conjugated with peroxidase and photometric registration of the enzymatic activity. The results indicate good permeability of the hydrogel pores for macromolecular biospecific reagents and suggest applications of thin reactive PVA hydrogels in photometric analytical techniques., (© 2019 The Authors.)

Effective technologies are required to remove organic micropollutants from large fluid volumes to overcome present and future challenges in water and effluent treatment. A novel hierarchical composite filter material for rapid and effective removal of polar organic contaminants from water was developed. The composite is fabricated from phenolic resin-derived carbon microbeads with controllable porous structure and specific surface area embedded in a monolithic, flow permeable, poly(vinyl alcohol) cryogel. The bead-embedded monolithic composite filter retains the bulk of the high adsorptive capacity of the carbon microbeads while improving pore diffusion rates of organic pollutants. Water spiked with organic contaminants, both at environmentally relevant concentrations and at high levels of contamination, was used to determine the purification limits of the filter. Flow through tests using water spiked with the pesticides atrazine (32 mg/L) and malathion (16 mg/L) indicated maximum adsorptive capacities of 641 and 591 mg pollutant/g carbon, respectively. Over 400 bed volumes of water contaminated with 32 mg atrazine/L, and over 27,400 bed volumes of water contaminated with 2 μg atrazine/L, were treated before pesticide guideline values of 0.1 μg/L were exceeded. High adsorptive capacity was maintained when using water with high total organic carbon (TOC) levels and high salinity. The toxicity of water filtrates was tested in vitro with human epithelial cells with no evidence of cytotoxicity after initial washing., (Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Stones located in the UPJ are accompanied by the most severe violation of the upper urinary tract urodynamics compared to other localizations of stones, which often leads to severe septic complications requiring emergency care. The study has evaluated the results of treatment of 147 patients with UPJ stones using various methods of treatment, and their efficacy in these patients. Extracorporeal shockwave lithotripsy (ESWL) was performed in 55 patients, contact ureterolithotripsy (CULT)--in 23 patients, percutaneous nephroureterolithotripsy and nephroureterolithoextraction (PCNLT and PCNLE)--in 43 patients, and open surgery (ureterolithotomy, pelviolithotomy)--in 26 patients. The best results in all parameters were obtained from patients with stone size up to 1 cm after ESWL, as well as in patients with stone size greater than 1 cm after PCNLT (PCNLE). In these groups, full discharge of stone at 3 months after treatment was achieved in 95 and 97.7% of patients, respectively. Complications in the ESWL group were recorded in 14.6% of patients, in the PCNLT (PCNLE) group--in 9.2% of patients.

Macroporous monolithic composites with embedded divinylbenzene-styrene (DVB-ST) polymeric particles were prepared by cryogelation techniques using poly(vinyl alcohol) or agarose solutions. Scanning electron microscopy images showed multiple interconnected pores with an average diameter in the range of 4 to 180 μm and quite homogeneous distribution of DVB-ST particles in the composites. Biocompatibility of the composites was assessed by estimation of the C5a fragment of complement in the blood serum and concentration of fibrinogen in the blood plasma which contacted the composites. A time-dependent generation of C5a fragment indicated weak activation of the complement system. At the same time, the difference in fibrinogen concentration, one of the most important proteins in the coagulation system of the blood, between the pristine blood plasma and the plasma, circulated through the monolithic columns, was insignificant.

The article presents the results of 42 retrograde nephrolithotripsy (RNLT) performed on 38 patients with staghorn nephrolithiasis. The staghorn cacculi SN-2 were most frequently indication for the intervention. 3 months after surgery, full exemption of the kidney from the fragments was observed in 85,6% of patients. RNLT is an effective and safe treatment for patients with staghorn stones with relatively low need for additional procedures. RNLT allows to reduce postoperative hospital stay and recovery period of patients.

Adsorption of myoglobin (Mb), bovine serum albumin (BSA) and γ-globulin (GG) onto activated carbons (ACs) with different pore size distributions, and poly(vinyl alcohol) (PVA) monolithic cryogels containing AC particles was studied. The highest initial rate of Mb adsorption was observed for AC having the largest specific surface area (1939 m(2) g(-1)) and pore volume (1.82 cm(3) g(-1)). The adsorption kinetics of proteins was characterized by a bimodal shape of the distribution f(D) function of an effective diffusion coefficient. Adsorption isotherms of Mb and GG were of Freundlich type within the studied range of equilibrium concentrations (10-150 μg mL(-1)). The distributions of free energy of protein adsorption were bimodal and reflected both interactions with carbon surfaces and self-association of proteins. Adsorbed amounts of Mb were the highest among the proteins studied (up to 700 mg g(-1) carbon), which was attributed to the higher fraction of pores accessible for Mb. Incorporation of carbon particles into PVA-based cryogel resulted in macroporous monolithic composite materials (AC-PVA) exhibiting good flow-through properties. Scanning electron microscopy of the composites showed macroporous aggregates of carbon particles held together by films and bridges of PVA. The rates of adsorption and adsorbed amounts of proteins on AC-PVA were reduced compared to the pristine carbon and depended on the carbon content in the composites. Nevertheless, adsorption of Mb on AC-PVA took place even in the presence of 500-fold higher concentration of BSA. This indicated a possibility of Mb clearance from blood plasma using the PVA-carbon monoliths.

A set of glutaraldehyde (GA) cross-linked poly(vinyl alcohol)/activated carbon (PVA/GA/AC) composites prepared in the form of monolithic rods using a cryogelation technique and studied using adsorption, mercury porosimetry, scanning electron microscopy (SEM), and quantum chemistry methods display porosity similar to that of PVA/GA cryogel at a high GA content (content ratio GA/AC = 1 and GA/PVA = 0.2). GA cross-linked PVA multilayer coverage is an effective barrier for adsorption on AC particles. Variations in surface chemistry (AC initial and oxidized in air at 300 °C for 12 h) and content (14-62.5%w/w) of ACs in PVA/GA/AC composites relatively weakly affect their textural characteristics at a high GA content (specific surface area S(BET) < 120 m²/g, pore volume V(p) < 0.35 cm³/g). However, PVA/GA/AC composite rods formed with a lower concentration of GA (content ratio GA/AC = 1/6 and GA/PVA = 1/10) have significantly greater S(BET) (∼500 m²/g) and V(p) (>0.55 cm³/g) values because of improved accessibility of the AC surface. This provides better adsorption of methylene blue as a probe compound.

A total of 323 transcutaneous roentgenoendoscopic operations were made in 212 patients from January 2000 to December 2009 including 96 operations in 81 presenile and senile patients (87 and 9 operations, respectively). Transcutaneous nephrolithotripsy (TCNT) eliminated concrement from the kidney for one session in 59 (72.8%) patients. It proved to be the most sparing treatment in serious clinical situations and provided maximally complete evacuation of the concrement from the kidney. A total complication rate was 14.8%. All the complications were cured with conservative pharmacotherapy. TCNT has the same indications as open surgery, is a method of choice in presenile and senile patients with large, stag-horn and recurrent concrements of the kidney, impacted pelvicoureteral concrements, in impaired renal urodynamics and high bacteriuria. TCNT can be used as a second-line treatment in failure of extracorporeal shock-wave lithotripsy or in combination with it (sandwich-therapy) for complete concrement elimination.

Reversible changes of the height of a polymer brush containing phenylboronic acid were studied. The polymer brush thickness underwent reversible changes of 0.5-1 nm, in response to the changes in composition of the contacting aqueous phase from deionized water to bicarbonate buffer and vice versa, apparently due to the conformational transition of the weak polyelectrolyte to the more extended electrically charged state. Adsorption of mucin glycoprotein to the polymer brush took place due to boronate/sugar interactions between the glycoprotein and the graft copolymer and resulted in further increase of the brush height by ca. 1.5 nm, as observed by means of spectral correlation spectroscopy and ellipsometry., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Boronate-containing thin polyacrylamide gels (B-Gel), polymer brushes (B-Brush) and chemisorbed organosilane layers (B-COSL) were prepared on the surface of glass slides and studied as substrates for carbohydrate-mediated cell adhesion. B-COSL- and B-Brush-modified glass samples exhibited multiple submicron structures densely and irregularly distributed on the glass surface, as found by scanning electron microscopy and atomic force microscopy. B-Gel was ca. 0.1 mm thick and contained pores with effective size of 1-2 microm in the middle and of 5-20 microm on the edges of the gel sample as found by confocal laser scanning microscopy. Evidence for the presence of phenylboronic acid in the samples was given by time-of-flight secondary ion mass-spectrometry (ToF SIMS), contact angle measurements performed in the presence of fructose, and staining with Alizarin Red S dye capable of formation specific, fluorescent complexes with boronic acids. A comparative study of adhesion and cultivation of animal cells on the above substrates was carried out using murine hybridoma M2139 cell line as a model. M2139 cells adhered to the substrates in the culture medium without glucose or sodium pyruvate at pH 8.0, and then were cultivated in the same medium at pH 7.2 for 4 days. It was found that the substrates of B-Brush type were superior both regarding cell adhesion and viability of the adhered cells, among the substrates studied. MTT assay confirmed proliferation of M2139 cells on B-Brush substrates. Some cell adhesion was also registered in the macropores of B-Gel substrate. The effects of surface microstructure of the boronate-containing polymers on cell adhesion are discussed. Transparent glass substrates grafted with boronate-containing copolymers offer good prospects for cell adhesion studies and development of cell-based assays.

We studied efficacy of transcutaneous nephrolithotripsy (TNLT) in patients with urolithiasis and anomalous upper urinary tract. For two years we performed TNLT in 148 patients with complicated forms of urolithiasis and anomalous kidneys (age 18-86, 76 females and 72 males). The examination for urolithiasis has found different anomalies of the urinary tract in these patients: double pelvis and ureter (9 cases--6.1%), lumbar dystopy of the kideney (59 cases--39.9%), horseshoe kidney (12 cases--8.1%), solitary cyst of the kidney (43 cases--29.0%), parapelvic cysts (25 cases--16.9%). Extracorporeal shock-wave lithotripsy (ESWL) was conducted as first-line treatment in the other 139 patients with nephroliths under 1.5-2 cm in size who had the following anomalies of the urinary system: a solitary kidney (n=14), double pelvis and ureter (n=26), anomalous position of the kidney (n=46), anomalous shape of the kidney (n=20), simple and parapelvic cysts (n=33). A total of 154 TNLT were performed in 148 patients. Transcutaneous interventions were most frequent in the treatment of coral (31.3%) and pelvoureteral (14.6%) concrements, one-stage operation was made in 143 patients. Transcutaneous puncture nephrostomy as the first stage was made in 5 patients. The concrements were removed by one operative intervention in 132 (89.2%) out of 148 patients. Exacerbation of pyelonephritis as a postoperative complication was treated conservatively in 12.5% patients. Residual fragments were diagnosed in 16 patients. Of them, 11 patients had multiple and 5 patients had coral concrements. Residual fragments were removed in 14 patients either by renephroscopy or by ESWL. Treatment of 139 patients with concrements less than 1.5-3 cm in size consisted in 197 ESWL sessions. In combination of anomaly and urolithiasis the number of lithotripsy sessions per one patient was 1.8 +/- 0.2. The least number of ESWL sessions per one patient was conducted in patients with lumbar dystopy of the kidney (1.3 +/- 0.45), the greatest number in horseshoe kidney (3.8 +/- 0.8). Evacuation of the concrements after ESWL depended on the type of anomaly and concrement location. It was 61-69% in patients with anomaly of the shape and position of the kidney, in cystic anomalies is was 89-91%. Open surgery was indicated in 7 patients who needed plastic surgery of hydronephrosis (4) and obstructive megaureter (3). Thus, low-invasive operations provide high efficacy of urolith removal in patients with anomalies of the urinary tract and can replace traumatic open operations.

A total of 1100 sessions of extracorporeal shock wave lithotripsy (ESWL) were made in 720 patients with urolithiasis in the last decade with application of LGK-Compact lithotripter which generates shock waves electrodynamically and has no focusing lens. Such lithotriptor allows ESWL in patients with a high anesthesiological risk. Fitting the LGK-Compact lithotriptor with an endourological complex ENDO-MIT tooled for low-invasive interventions under X-ray control enabled treatment of 467 patients with urolithiasis aged 30-80 years. Most of the patients (66.04%) were at the productive age of 18-50 years. ESWL on the LGK-Compact lithotriptor was made in 182 patients (mean number of sessions was 2.1). Six and 12 month follow-up examinations registered complete elimination of the fragments in 169 patients. Thirty-four patients with concrements of the intramural ureter were exposed to 1 to 3 sessions. The fragments eliminated for 1-14 days after the session in 25 patients. Three patients developed stone path which evacuated spontaneously in two cases. For 3 years transcutaneous nephrolithotripsy was conducted in 214 patients. The concrements were removed during one operation in 156 (72.9%) patients, 58 (26.1%) patients had residual fragments. Reoperation was made in 34 patients 7-12 days after the first intervention. In the rest 24 cases (11.2%) residual fragments were removed by means of ESWL on LGK-Compact. Thus, ESWL is a leading technique in management of uncomplicated uroliths maximum 2 cm in size. When indications to ESWL are limited or this method is not effective, the role of roentgenoendoscopic interventions, such as transcutaneous nephrolithotripsy and transurethral contact ureterolithotripsy, takes on special significance. Such clinical innovation as endourological complex ENDO-MIT with lithotripter LGK-Compact made in Russia opens new perspectives of the treatment of urolithiasis and other urological diseases due to introduction of novel highly effective domestic technologies leading to a significant reduction in the number of postoperative complications and time of treatment, to 1.5-2 fold reduction in costs of equipment compared to foreign analogues.

Boronate-containing polymer brushes were synthesized by free radical copolymerization of N,N-dimethylacrylamide (DMAA) and N-acryloyl-m-phenylboronic acid (NAAPBA) (9:1) on the surface of 3-mercaptopropyl-silylated glass plates and capillaries. The brushes were characterized with time-of-flight secondary ion mass-spectrometry (ToF SIMS), atomic force microscopy and contact angle measurements. Fructose caused a well-expressed drop spreading on the surface of copolymer-grafted glass, due to the strong interaction with the boronate groups. Sedimentation of murine hybridoma cells M2139 or human myeloid leukemia cells KG1 onto the DMAA-NAAPBA copolymer-grafted glass plates from 10 mM phosphate buffer solution (pH 8.0) resulted in the cell adhesion. The adhered M2139 and KG1 cells could be quantitatively detached from the grafted plates with 0.1 M fructose, which competed with cell surface carbohydrates for binding to the boronates. Evaluation of the binding strength between M2139 cells and the copolymer brush was performed by exposure of the adhered cells to a shear stress. Detachment of a fraction of 18% of the adhered M2139 cells was obtained at a shear force of 1400-2800 pN/cell generated by the running phosphate buffer (pH 8.0), whereas the remaining adhered cells (70%) could be detached with 0.1 M fructose dissolved in the same buffer. Possible applications of the boronate-containing polymer brushes to affinity cell separation can be based upon the facile recovery of the attached cells., (2008 Wiley Periodicals, Inc.)

Copolymers of N-acryloyl-m-aminophenylboronic acid (NAAPBA) with N,N-dimethylacrylamide (DMAA) formed insoluble interpolymer complexes with mucin from porcine stomach at pH 9.0. The complex formation based on boronate-sugar interactions took place between the similarly charged macromolecules and resulted in coacervate particles formation, which depended both on pH and ionic strength of the solution. The coacervation rate displayed a maximum at the intermediate DMAA-NAAPBA copolymer: mucin weight ratio, that is a pattern typical of interpolymer complex formation. The effective hydrodynamic particle diameter of the coacervates monotonously grew from 155+/-20 nm up to 730+/-120 nm in 2 days in 0.1M sodium bicarbonate buffer solution, pH 9.0. Electrophoretic mobility of the resultant nanoparticles was intermediate between those of individual polymers, whereas the particles zeta-potential was -7.5+/-0.4 mV in the above buffer solution. Pre-treatment of the inner mucosal epithelium of excised male pig urethras with 5% (w/v) solutions of acrylamide-NAAPBA or DMAA-NAAPBA copolymers at pH 8.8 allowed for tight occlusion of the lumen by poly(vinyl alcohol)-borax gel injected via a two-way catheter. Leakage of 0.15M NaCl solution through the thus occluded organs could be prevented, while the leakage through the organs occluded by the gel without the pre-treatment was unavoidable. The gel plug could be quickly dissolved on demand after injection of 5% (w/v) aqueous fructose solution into the lumen. The described technique may be useful for temporal occlusion of mucosal lumens in living organisms. In contrast to the conventional mucoadhesive polymers like polyacrylic acid or chitosan, the boronate-containing copolymers display their mucoadhesivity at weakly alkaline pH of 8-9 and physiological ionic strength.

Radical copolymerization of acrylamide (Am) (90 mol%) with N-acryloyl-m-aminophenylboronic acid (NAAPBA) (10 mol%) carried out on the surface of glass slides in aqueous solution and in the absence of chemical cross-linkers, resulted in the formation of thin semitransparent gels. The phenylboronic acid (PBA) ligand density was ca. 160 micromol/ml gel. The gels exhibited a macroporous structure and displayed optical response to sucrose, lactose, glucose and fructose in 50 mM sodium phosphate buffer, in the pH range from 6.5 to 7.5. The response was fairly reversible and linearly depended on glucose concentration in the wide concentration range from 1 to 60 mM at pH 7.3. The character of response was explained by the balance of two competing equilibrium processes: binding of glucose to phenylboronate anions and binary hydrophobic interactions of neutral PBA groups. The apparent diffusion coefficient of glucose in the gels was ca. 2.5 x 10(-7) cm(2)/s. A freshly prepared gel can be used daily for at least 1 month without changes in sensitivity. Autoclaving (121 degrees C, 1.2 bar, 10 min) allows for the gels sterilization, which is important for their use as glucose sensors in fermentation processes., (2008 John Wiley & Sons, Ltd.)

Affinity precipitation of proteins uses polymers capable of reversible soluble-insoluble transitions in response to small environmental changes (temperature, pH or solvent composition). Here we describe protocols for (i) the synthesis of responsive polymers with specific affinity to target proteins and (ii) the purification of proteins using these polymers. The purification is based on precipitation of the affinity complex between the protein and the polymer, which is induced by environmental changes. This separation strategy is simpler and more cost effective than conventional affinity column chromatography. Specifically, we describe the synthesis of thermoresponsive 1-vinylimidazole:N-isopropylacrylamide copolymers. The whole procedure takes 2-3 h when applied to purification of recombinant His-tag proteins or proteins with natural metal binding groups by means of metal chelate affinity precipitation. Optimization of the polymer composition and the type of chelating ions allows for target protein yields of 80% and higher.

Cross-linked agarose particles (Sepharose CL-6B) and baker's yeast cells were found to adhere to siliceous supports end-grafted with boronate-containing copolymers (BCCs) of N,N-dimethylacrylamide at pH> or =7.5, due to boronate interactions with surface carbohydrates of the particles and the cells. These interactions were registered both on macroscopic and on molecular levels: the BCCs spontaneously adsorbed on the agarose gel at pH> or =7.5, with adsorption increasing with pH. Agarose particles and yeast cells stained with Procion Red HE-3B formed stable, monolayer-like structures at pH 8.0, whereas at pH 7.0-7.8 the structures on the copolymer-grafted supports were less stable and more random. At pH 9.0, 50 % saturation of the surface with adhering cells was attained in 2 min. Stained cells formed denser and more stable layers on the copolymer-grafted supports than they did on supports modified with self-assembled organosilane layers derivatized with low-molecular-weight boronate, presumably due to a higher reactivity of the grafted BCCs. Quantitative detachment of adhered particles and cells could be achieved by addition of 20 mM fructose--a strong competitor for binding to boronates--at pH 7.0-9.0. Regeneration of the grafted supports allowed several sequential adhesion and detachment cycles with stained yeast cells. Affinity adhesion of micron-sized carbohydrate particles to boronate-containing polymer brushes fixed on solid supports is discussed as a possible model system suggesting a new approach to isolation and separation of living cells.

Interaction of mono- and disaccharides, polysaccharide particles and yeast cells with boronate-containing copolymers (BCC) of N-acryloyl-m-aminophenylboronic acid (NAAPBA) with N,N-dimethylacrylamide (DMAA) or N-isopropylacrylamide (NIPAM) was studied. The binding of saccharides to BCC of NIPAM resulted in a shift of its phase transition temperature (DeltaTP), which provided a quantitative measure for the complex formation. Among the sugars typical of non-reducing ends of glycoproteins the DeltaTP decreased in the order: N-acetylneuraminic acid > xylose approximately galactose > mannose approximately fucose >> N-acetylglucosamine. Strong specific adsorption of the BCC on the cross-linked agarose gel Sepharose CL-6B (15-30 mg/ml gel at pH 9.2) was registered. The copolymers adsorption was due to boronate-sugar interactions and decreased with pH. Multivalent interaction of the BCC with the agarose gel has been proven by liquid column chromatography exhibiting a weak reversible adsorption of NAAPBA and almost irreversible adsorption of DMAA-NAAPBA copolymer from 0.1 M sodium phosphate buffer, pH 7.9. The two studied BCCs could be completely desorbed from the gel by 0.1 M fructose in aqueous buffered media with pH from 7.5 to 9.2. In turn, the agarose particles and yeast cells were found to adhere to siliceous supports end-grafted with boronate-BCC of N,N-dimethylacrylamide at pH > or = 7.5, due to the actions. Quantitative detachment of adhered particles or cells could be attained by addition of 20 mM or 100 mM fructose, respectively, in the pH range from 7.5 to 9.2. Affinity adhesion of micron-size carbohydrate particles to boronate-containing polymer brushes fixed on solid supports was considered as a model system suggesting a new approach to isolation and separation of living cells., (Copyright 2006 John Wiley & Sons, Ltd.)

Poly(N-isopropylacrylamide), a thermally responsive polymer, was end-grafted to mercaptopropyl derivatives of silica gel, plane glass sheets and glass capillary tubing by free radical polymerization of the monomer in 1,4-dioxane at 100 degrees C. The polymer monolayer attached to the glass carriers provided them with thermally controlled wettability registered by two independent methods: direct measurements of the water contact angle and capillary rise. The water contact angle changed from 54+/-3 degrees to 68+/-3 degrees in the temperature range from 20 to 50 degrees C. The polymer grafting to silica gel (pore diameter 100 A, particle size 5 microm) resulted in 15-30-fold reduction in protein adsorption on the carrier at 35 degrees C. Adsorption isotherms of myoglobin indicate completely different characters of the protein adsorption to silica gel and its polyNIPAM-grafted derivative. Cooling of the grafted carrier containing adsorbed myoglobin to 9 degrees C led to a partial release of the protein to the contacting solution, whereas heating of the system to 35 degrees C resulted in reversible binding of the protein. Adsorption of myoglobin on polyNIPAM-coated silica was ca. 2-fold higher at 35 than at 9 degrees C, most probably due to steric repulsion displayed by the swollen copolymer at the lower temperature.

The copolymer of 3-(acrylamido)phenylboronic acid and N-isopropylacrylamide (82:18, Mn = 47000 g/mol) was prepared by free radical polymerization. The copolymer showed typical thermoprecipitation behavior in aqueous solutions; its phase transition temperature (TP) was 26.5 +/- 0.2 degrees C in 0.1 M glycine-NaOH buffer containing 0.1 M NaCl, pH 9.2. Due to specific complex formation of the pendant boronates with sugars, TP was strongly affected by the type of sugar and its concentration at pH 9.2. Fructose, lactulose, and glucose caused the largest increase in TP (up to 4 degrees C) at 0.56 mM concentration, attributed to the high binding affinity of the sugars to borate and phenylboronate. Among the sugars typical of nonreducing ends of oligosaccharides, N-acetylneuraminic acid had the strongest effect on TP (ca. 2 degrees C at 0.56 mM concentration and pH 9.2), while the effects of other sugars are well expressed at the higher concentrations (16 and 80 mM) and decreased in the order xylose approximately galactose >or= N-acetyllactosamine >or= mannose approximately fucose >> N-acetylglucosamine. The effect exerted on the phase transition by glycoproteins was the strongest with mucin from porcine stomach and decreased in the series mucin > horseradish peroxidase > human gamma-globulin at pH 9.2. As a first approximation, the weight percentage and/or the number of oligosaccharides in glycoproteins determined the character of their interaction with the pendant phenylboronates and, therefore, the effect on the copolymer phase transition.

Copolymers of N-acryloyl-m-aminophenylboronic acid (NAAPBA) with acryamide (AA), N,N-dimethylacrylamide (DMAA), and N-isopropylacrylamide (NIPAM) were found to adsorb on cross-linked agarose gel (Sepharose CL-6B) in the pH range from 7.5-9.2, due to specific boronate-sugar interactions. The molar percentages of phenylboronic acid (PBA) groups in the boronate-containing copolymers (BCCs), as estimated by 1H NMR spectroscopy, were 13, 10, and 16%, respectively, whereas the apparent ionization constants, the pKa values, of the copolymers were similar and equal to 9.0 +/- 0.2 at 20 degrees C. The copolymers adsorption capacities were in the range of 15-30 mg x ml(-1) gel (14-36 micromol pendant PBA ml(-1) gel) at pH 9.2 and decreased with decreasing pH value. The interaction of monomeric NAAPBA with Sepharose CL-6B was characterized by an equilibrium association constant of 53 +/- 17 M(-1), the chromatographic capacity factor k' = 1.8, and a total content of binding sites of 27 +/- 10 micromol x ml(-1) gel at pH 9.2. The weak reversible binding of monomeric NAAPBA and almost irreversible binding of NAAPBA copolymers to the gel at pH 9.2 suggested a multivalent character of the copolymer adsorption. At pH 7.5, the maximal adsorption capacity was displayed by the AA-NAAPBA copolymer (15 mg x ml(-1) gel). All the BCCs could be completely desorbed from the gel by 0.1 M fructose in aqueous buffered media with pH values from 7.5-9.2. The strong adsorption of AA-NAAPBA on agarose gel probably relates to the conformation of the copolymer in aqueous solution and provides opportunities for biomedical applications of the copolymer under physiological conditions. Multivalent, weak-affinity adsorption of BCCs to the agarose gel seems to be a tentative model for the copolymers' binding to oligo- and polysaccharides of cell membranes and mucosal surfaces.

Binding of adenosine to the thermosensitive copolymer of N-isopropylacrylamide and 3-(acrylamido)aminophenylboronic acid (82:18, Mn = 47,000 g . mol(-1)) was studied by equilibrium dialysis at 22 degrees C and 37 degrees C, in a 0.1 M glycine buffer containing 0.1 M NaCl at pH 9.2. The copolymer exhibited a the phase transition temperature (T(p)) of 26.5 degrees C under the above conditions. At 22 degrees C the binding of adenosine to the water-soluble copolymer was well described by a Langmuir model, accounting for preferential ionisation of the boronate-nucleoside complexes and, therefore, restricted reactivity of the rest of boronates. At saturation, the copolymer contained 38% of its phenylboronic acid groups in the form of complexes, whereas the association constant was 1,400 M(-1). At 37 degrees C no binding of adenosine to thermally precipitated copolymer was found, presumably owing to interaction of the phenylboronates with hydrophobic segments of polyNIPAM. At high loading of the copolymer by the reversibly bound adenosine the T(p) steeply increases with increasing fraction of the phenylboronate-adenosine complexes in the chains. The increase of the T(p) observed above the saturating adenosine concentration (>1 x 10(-3) M, 22 degrees C) very probably testifies to competition of the nucleoside with hydrophobic polyNIPAM segments for binding to the pendant phenylboronates.

Conjugation of penicillin acylase (PA) to poly-N-isopropylacrylamide (polyNIPAM) was studied as a way to prepare a thermosensitive biocatalyst for industrial applications to antibiotic synthesis. Condensation of PA with the copolymer of NIPAM containing active ester groups resulted in higher coupling yields of the enzyme (37%) compared to its chemical modification and copolymerization with the monomer (9% coupling yield) at the same NIPAM:enzyme weight ratio of ca. 35. A 10-fold increase of the enzyme loading on the copolymer resulted in 24% coupling yield and increased by 4-fold the specific PA activity of the conjugate. Two molecular forms of the conjugate were found by gel filtration on Sepharose CL 4B: the lower molecular weight fraction of ca. 10(6) and, presumably, cross-linked protein-polymer aggregates of MW > 10(7). Michaelis constant for 5-nitro-3-phenylacetamidobenzoic acid hydrolysis by the PA conjugate (20 microM) was found to be slightly higher than that of the free enzyme (12 microM), and evaluation of V(max) testifies to the high catalytic efficiency of the conjugated enzyme. PolyNIPAM-cross-linked PA retained its capacity to synthesize cephalexin from d-phenylglycin amide and 7-aminodeacetoxycephalosporanic acid. The synthesis-hydrolysis ratios of free and polyNIPAM-cross-linked enzyme in cephalexin synthesis were 7.46 and 7.49, respectively. Thus, diffusional limitation, which is a problem in the industrial production of beta-lactam antibiotics, can be successfully eliminated by cross-linking penicillin acylase to a smart polymer (i.e., polyNIPAM).

The precipitation of N-cetylamine, N-cetylacetamide, hexan-1,2-diol, cetyl alcohol, and poly(butyl metacrylate) in acetone-water media in the presence of the lipase from Pseudomonas fluorescens was found to be accompanied by the coprecipitation of the enzyme. Within the lyophilized coprecipitates, the lipase exhibits a high catalytic activity and enantioselectivity in the reaction of (1RS)-phenylethanol acetylation with vinyl acetate in t-butyl methyl ether. In order of increasing lipase activity, the coprecipitates can be arranged in the series: cetyl alcohol, poly(butyl metacrylate), hexadecane-1,2-diol, N-cetylamine, and N-cetylacetamide, with the activity 2.5- to 19-fold exceeding the activity of the native enzyme. The immobilization of the lipase on solid supports, such as Celite 545 (physical sorption) and Eupergit C250L (covalent binding), in the presence of hexadecane-1,2-diol was found to increase the esterifying activity of the enzyme. The English version of the paper.

Successful immobilized metal affinity chromatography (IMAC) of proteins on Cu2+-iminodiacetic acid Sepharose has been carried out in a displacement mode using a synthetic copolymer of vinyl imidazole and vinyl caprolactam [poly(VI-VCL)] as a displacer. Vinyl caprolactam renders the co-polymer with the thermosensitivity, e.g., property of the co-polymer to precipitate nearly quantitatively from aqueous solution on increase of the temperature to 48 degrees C. A thermostable lactate dehydrogenase from the thermophilic bacterium Bacillus stearothermophilus modified with a (His)6-tag [(His)6-LDH] has been purified using an IMAC column. For the first time it was clearly demonstrated that a polymeric displacer [poly(VI-VCL)] was more efficient compared to a monomeric displacer (imidazole) of the same chemical nature, probably due to the multipoint interaction of imidazole groups within the same macromolecule with one Cu2+ ion. Complete elution of bound (His)6-LDH has been achieved at 3.7 mM concentration of imidazole units of the co-polymer (5 mg/ml), while this concentration of free imidazole was sufficient to elute only weakly bound proteins. Complete elution of (His)6-LDH by the free imidazole was achieved only at concentrations as high as 160 mM. Thus, it was clearly demonstrated, that the efficiency of low-molecular-mass displacer could be improved significantly by converting it into a polymeric displacer having interacting groups of the same chemical nature.

Synthetic copolymers of N-vinylcaprolactam (VCL) and N-vinylimidazole (VI) were studied as thermosensitive, reusable displacers for immobilised metal affinity chromatography (IMAC) of proteins. The copolymer with weight-average molecular mass of 11700 g/mol prepared by free radical polymerisation at a 9:1 monomer molar ratio was separated into several fractions by IMAC and thermal precipitation. The fraction with an average VI content of 8.5% was most efficient as a reusable displacer for IMAC of ovalbumin, lysozyme and other proteins of egg white on Cu2+-IDA-Sepharose. The displacer exhibited a sharp breakthrough curve and binding capacity of 16-20 mg/ml gel, depending on the flow-rate. The recovery of egg white proteins in the course of displacement chromatography was >95%. The displacer could be removed quantitatively from the protein fractions by thermal precipitation at 48 degrees C. Co-precipitation of lysozyme with the displacer was minimal in the presence of 3% (v/v) acetonitrile, while the lysozyme enzymatic activity in the supernatant was completely retained. Addition of free imidazole to the mobile phase increased the rate of protein desorption and allowed better separation of egg white proteins and the displacer in the course of chromatography. The displacement profile of the egg white extract consisted of three zones with different distributions of individual proteins characterised by SDS-PAGE. Regeneration of the column was easily performed with 0.02 M EDTA in 0.15 M sodium chloride, pH 8.0, followed by washing with distilled water and reloading with Cu2+. The displacer could also be regenerated by thermal precipitation at 48 degrees C and subsequent dialysis against dilute hydrochloric acid (pH 2.5).

A simple method for determining the enzymic hydrolysis parameters of lipid-like substrates and trilaurin assembled in monolayers at the water-air interface was suggested. At a surface pressure of 10 mN/m, the initial rates of lipolysis were found to be proportional to the decrease in area of the substrate monolayer caused by the enzymic hydrolysis in a single-compartment Langmuir balance. The kinetic parameters for the hydrolysis of trilaurin and three 1,3-dilaurylpseudoglycerides acetylated in position 2 with an amino acid (phenylalanine, leucine, or valine) catalyzed with lipase from Pseudomonas fluorescens were determined. Unlike models of enzymic hydrolysis that neglect the thickness of the substrate monolayer, our method allows the determination of kinetic parameters in standard dimensions. The values of kcat for the synthetic pseudoglycerides were found to be significantly higher than that for trilaurin, while the values of Km(app) were close. This may be due to the presence of positively charged primary amino groups in the molecules of pseudoglycerides.

This review describes new polymer materials for biomedical applications developed in the Polymers for Biology Laboratory of the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences. These include composite rigid sorbents for biochromatography, polymer dispersions for immunoassay, polymer hydrogels for immobilization of enzymes and cells, and polymer ultra thin films as biomembrane models and materials for biosensors. Some general and specific properties of these new materials and models as well as examples of their applications are discussed.

Results of treatment of 30 patients of 50 to 90 years of age having choledocholithiasis by the method of extracorporeal lithotripsy (EL) combined with endoscopic operations on the major duodenal papilla are described. The first stage in the treatment was endoscopic papillosphincterotomy. There were 41 sessions of EL (at an average 1,37 procedure for each patient). In 15 patients spontaneous excretion of the fragments from the common bile duct was noted. The endoscopic sanitation of the common bile duct with a removal of fragments with the Dormia basket was fulfilled in 13 patients after EL. The method of choledocholithotomy proved to be ineffective in 2 patients. Sanitation of the common bile duct was performed in all the patients before their discharge from the hospital. Thus the results obtained allow considering the extracorporeal biliary lithotripsy when combined with endoscopic papillosphincterotomy as an effective method for treatment of patients with choledocholithiasis which not only supplements traditional surgical procedures but also may be used as an alternative method of treatment especially for patients with high operative risk.

Composite sorbents based on wide-pore glass and silica coated with N-butyl polyacrylamide (butyl-PA-glass and butyl-PA-silica) were studied. The surface tension of butyl-PA-silica is 50-55 mJ/m2 as evaluated by the sedimentation volume technique. The linear dependences of log k' on ammonium sulphate concentration were determined by isocratic chromatography of the dipetide Trp-Trp and lysozyme on butyl-PA-glass. Both solutes were shown to have a weaker retention on butyl-PA-glass than on butyl-Toyopearl 650C. This weaker retention is beneficial in the purification of sialic acid-binding lectin from Bacillus subtilis.

The applicability of reversed-phase high-performance liquid chromatography (HPLC) to the analysis of the products of recombinant insulin was studied. The influence of several mobile phases in reversed-phase and ion-pair HPLC on selectivity, resolution and sensitivity was investigated. Optimum conditions for the separation of insulin-related proteins on commercial and laboratory-made supports were established by means of three-dimensional optimizations of selectivity and resolution as a function of pH and ionic strength (mu). A mechanism for the separation of proteins with a mobile phase containing a high salt concentration and a pH near the isoelectric point of proteins is proposed. The questions of scaling up are considered. The proposed techniques allow the analysis of the main impurities and ensures a high quality of active insulin production.

The effectiveness of the RP HPLC application for the step-by-step analysis of the recombinant insulin production was studied. Properties of a number of commercial and experimental columns in different chromatographic conditions were considered. A three-dimension optimization of selectivity and resolution versus pH and ion strength was carried out. A mechanism of the resolution and selectivity control is suggested.

It is shown that 210Po in the complex with a sorbent can be fixed in the organs, particularly in the proximal renal tubules. This, in the authors' opinion, can be the cause of various complications of the therapy with the adsorbents including the development of tumours.

Several types of polymeric glycoconjugates, N-substituted polyacrylamides, have been synthesized by the reaction of activated polymers with omega-aminoalkylglycosides: (i) (carbohydrate-spacer)n-polyacrylamide, 'pseudopolysaccharides'; (ii) (carbohydrate-spacer)n-phosphatidylethanolaminem-polyacrylamide, neoglycolipids, derivatives of phosphatidylethanolamine; (iii) (carbohydrate-spacer)n-biotin-polyacrylamide, biotinylated probes; (iv) (carbohydrate-spacer)n-polyacrylamide-(macroporous glass), affinity sorbents based on macroporous glass, covalently coated with polyacrylamide. An almost quantitative yield in the conjunction reaction makes it possible to insert in the conjugate a predetermined quantity of the ligand(s). Pseudopolysaccharides proved to be a suitable form of antigen for activation of polystyrene and poly(vinyl chloride) plates (ELISA) and nitrocellulose membranes (dot blot), being advantageous over traditional neoglycoproteins. Polyvalent glycolipids insert well in biological membranes: their physical properties, particularly solubility, can be changed in a desired direction. Biotinylated derivatives were used as probes for detection and analysis of lectins.

Application of some variants of HPLC for the step-by-step analysis of recombinant human insulin production was studied. Chromatographic columns with commercial and specially developed supports for size-exclusion, ion-exchange and reverse phase HPLC were used. Effective combinations of the chromatographic techniques for analysis of products and intermediates at every technological step were found and used for production of insulin. The authenticity of insulin obtained in the Shemyakin Institute of Bio-organic Chemistry by the scheme described in the present paper was confirmed by means of some physical and chemical methods and biological activity analysis.

Blood group B antigenic trisaccharide-beta-aminopropyl glycoside (B-TSAP) covalently attached to poly-N-(2-hydroxyethyl)acrylamide-coated porous glass interacts with anti-B monoclonal antibodies faster than the ligand coupled to CNBr-activated Sepharose 4B and Affi-Gel 10. Rates of hydrophobic adsorption of antibodies on the butyl derivatives of the same supports were measured to evaluate the diffusion input to overall kinetics. The lowest average affinity adsorption time [t1(aff) = 250 s] observed for polymer-coated glass probably arises because of the flexibility of the extended segments of chemisorbed N-substituted polyacrylamide acting as effective spacer arms.

Materials are presented on six cases of fatal acute radiation disease consequent to relatively proportional beta- and gamma-irradiation after accident in the nuclear submarine. The comparison is performed of this material with the data published on the radiation sequelae of the Chernobyl nuclear catastrophe.

Wide porous glass (WPG) chemically coated with a poly-N-(2-hydroxyethyl)acrylamide layer is proposed as a carrier of biospecific ligands in affinity chromatography. The method of WPG chemical modification includes synthesis of the gamma-aminopropyl derivative followed by chemical adsorption of poly(p-nitrophenyl acrylate). Ester groups of the polyacrylate-coated WPG can be used for coupling the ligands bearing primary amino groups. Condensation of esters with ethanolamine yields a poly-N-(2-hydroxyethyl)acrylamide-coated support with non-specific adsorption properties resembling those of Sepharose 4B. Human IgG immobilized on the polyacrylate support was used for isolation of the first complement component from human serum and for its separation into subcomponents C1r, C1s and C1q by a one-step method. An unbound part of serum may be used as the R1 reagent for determining haemolytic C1 activity. The stepwise elution of C1r, C1s and C1q from the column reflects the course of C1 breakdown after its activation on immune complex formation.

A brief review of the pathology of human radiation sickness is presented. The author recommends providing information to the practitioners, including pathologists, of new data concerning the manifestations of acute radiation sickness at various forms of radiation damage induced in the extreme situations.

Biopsy specimens of the bone were examined and then subjected to morphometry in 49 patients with terminal renal failure. 43 patients were on chronic hemodialysis and 6 had undergone renal transplantation. Histomorphometry permitted calculating the relative area of the bone girdles in the preparation (in %), the relative resorption area (in %), and the osteocyte count per mm2 bone girdle. It is concluded that if the area of the bone girdle in the preparation is less than 23.8%, the patient on hemodialysis may be diagnosed as having dialysis osteomalacia. The reduction of the relative reabsorption area in patients with dialysis osteomalacia is insignificant and can be used as an auxiliary sign in differential diagnosis of renal osteopathies in patients on dialysis.

Quantitative changes of structural correlations of transplanted allogenic human kidneys were examined in the histological slides by means of computer micromorphometry. The measurements were performed in 663 transplants selected randomly which had been in the recipient's body from several hours till 14.5 years. As a result of the study, parameters of glomeruli, tubules, blood vessels and connective tissue in the overall mass of donor kidneys were established starting from the time before transplantation and 6 months, 1-1.5, 2-3, 4-5, 7-14.5 years after transplantation. A progressive increase of sclerotic changes in the transplant is confirmed and the hypotheses about their genesis are proposed.

The force trajectories of isometric wrist flexor efforts and corresponding EMG activity of forearm muscles were studied in healthy subjects. A target effort of 50 N was developed after the sound signal: the target level and force trajectory were displayed on the TV indicator. Force trajectories under conditions of visual control, kinesthetic control (without a visual target) and with random alternation of these regimens were compared. Wrist flexor EMG latencies were approximately equal under visual and kinesthetic control and noticeably longer when these conditions were alternated randomly. Relative error of the target effort reproduction and duration of late components of force trajectories were higher in absence of the visual target. When visual and kinesthetic regimes were alternated randomly the delay between EMG onset and force trajectory initiation increased; its values correlated positively with the duration of the first force derivative increase. Formation of different strategies for force trajectory correction under different experimental conditions is discussed.