[Recovery of spinal cord functions after experimental complete crossection under the effect of chitosan polymeric compounds]

Currently, there is no effective method of treating complete spinal cord intersection. One of the promising experimental approaches is substances promoting repair and fusion of axonal membranes.

OBJECTIVE

To study clinical and functional recovery in experimental animals with transected spinal cord after management with photo-cross-linked chitosan in a homogeneous mixture with polyethylene glycol.

MATERIAL AND METHODS

We studied 20 rabbits with a model of complete spinal cord transection at the level of Th9. There were control and experimental groups (n=10; n=10). In the experimental group, we intraoperatively injected photo-cross-linked chitosan in a homogeneous mixture with polyethylene glycol. Neurological status was assessed using the modified Basso Beattie Bresnahan scale. Histological examination was performed after removing the animals from the experiment.

RESULTS

In the experimental group, significant regression of neurological disorders was accompanied by partial recovery of movements, sensitivity and control of pelvic functions by the 30th day of the experiment. There was no mortality in the experimental group. Paraplegia and anesthesia persisted in the control group while mortality was 40% (n=4). Histological analysis in the main group revealed axonal «bridges» in the area of injury and spread of DiI dye through this area.

CONCLUSION

These phenomena confirm the positive effect of chitosan and polyethylene glycol on functional recovery after experimental spinal cord injury. These data are consistent with histological findings.

Influence of confectionery wastewater pretreatment in vortex layer apparatus on its physical and chemical properties

The paper studies the effect of pretreatment of highly concentrated wastewater from confectionery production in a vortex layer apparatus (VLA) on its physical and chemical properties, with the aim of its further use as a substrate for dark fermentation with the production of biohydrogen. Pretreatment in VLA resulted in a 2.6-fold increase in the iron content and 6.5% increase in soluble chemical oxygen demand after 3 minutes of exposure. After pretreatment in VLA, an increase in the content of acetic acid and a decrease in the contents of propionic, butyric and caproic acids were observed. An increase in the content of mono- and disaccharides was registered, and the effect of the VLA exposure time of confectionery wastewater on its physicochemical properties was studied. An increase in the concentration of iron and simple sugars in wastewater makes the use of VLA promising for improving the process of its subsequent dark fermentation.

[The influence of the drying method for food properties and hypolidemic potential of oyster mushrooms (Pleurotus ostreatus)]

The aim of this research was to study the influence of two drying methods: freeze-drying sublimation and dry-air drying on the selected nutritional properties and hypolipidemic potential of fruiting bodies of oyster mushroom (Pleurotus ostreatus). The criteria for evaluation of the food properties were the color, the morphological structure, regidratation capacity, the total level of soluble proteins, fats, polysaccharides, free amino acids and monosaccharides. Lipid-lowering potential of oyster mushroom was evaluated by the concentration of lovastatin and the level of antioxidant activity. It has been experimentally revealed that the value of optical density of hydro-alcohol extracts of dried oyster mushrooms at a wavelength of 295 nm most clearly characterized its color which intensity was almost twice less in sublimated mushrooms, than шт the sample dried by dry-air method. Histological data showed that dry-air drying lead to the destruction of the mushroom cells and to the formation of a dense layered structure. Sublimation drying preserved the ordered cell structure and provided less deformation and shrinkage of the tissues. Using X-ray microtomography it was reported that freeze-dried mushrooms had uniform pore volume distribution. Dry-air dehydration method lead to the formation of larger cavities. The average percentage of the open pores was: 29.41±0.52% (after dry-air method), 11.10±0.41% (after freeze-drying method). Respectively the number of closed pores, which reflected the true value of porosity, was 0.99±0.01 and 1.75±0.01%. Structural differences of the samples of the dry oyster mushroom combined with their unequal hydration ability. Indicator of rehydration for oyster mushroom dried by sublimation method was 5.4±0.1, and for samples obtained by dry-air method it was 3.2±0.1. Respectively the average time of maximum water absorption was 22.7±1.8 and 45.3±2.9 minutes. It was found that the freeze-drying sublimation conditions were more conducive for the preservation of the biologically active protein and polysaccharide components of oyster mushrooms and on the other hand dry-air drying method increased the nutritional value of oyster mushrooms due to the reactions of polysaccharides autohydrolysis. The number of proteins and polysaccharides of the Oyster mushrooms samples dried by dry-air method and freeze-drying method was 72.0% and 56.0% respectively. Concentrations of free amino acids and glucose in the samples dried by freeze-drying and dry-air methods were 11.60±0.31%; 175.20±6.10 mg% and 7.00±0.28%; 144.0±5.7 mg% respectively. It has been experimentally recorded that the conditions of freeze drying were optimal in terms of ensuring the preservation of the content of natural statin and the antioxidant capacity of oyster mushrooms that provided its hypolipidemic potential. The amount of lovastatin in an the freeze-dried samples was 342±9.0 mg/kg, and was significantly higher than in the samples received by dry-air method - 190±6.0 mg/kg. The level of antioxidant activity of the oyster mushrooms samples were respectively 3.83±0.02 against 2.0±0.03 mmol/100 g. The conducted researches proved that for the production of dry oyster mushroom as a potential biologically active feedstock for the functional food products with lipid-regulating directivity the choice of the drying method had a fundamental importance.

[Production of Methane in Anaerobic Digestion of Organic Waste of Vegetable Processing Facilities]

The article concerns converting waste from vegetable processing facilities into methane in anaerobic reactors with a small amount of inoculum (8.4%). Anaerobic digestion of vegetable waste with a high content of organic acids and carbohydrates makes it possible to achieve a methanogenesis productivity of 273–436 L CH4/kg of volatile solidis, which is comparable to or higher than the productivity of such reactors in the world (according to the literature). The contents of ammonia nitrogen and soluble phosphorus in the form of on undiluted substrate basis in the digested vegetable wastes ranged from 3.39 to 5.06 and from 0.78 to 1.03 g/L respectively. Thus, mineralized vegetable waste can be used as an organic fertilizer with a high nutrient content. The results show the feasibility of the technology of conversion of organic waste from vegetable processing facilities into methane and organic fertilizer in anaerobic fermenters (digesters).

[RETROSPECTIVE ANALYSIS OF BIOLOGICAL AND MOLECULAR-GENETIC PROPERTIES OF STRAINS - CAUSATIVE AGENTS OF CHOLERA - ISOLATED IN UKRAINE IN 1994 - 2011]

AIM

Retrospective analysis of biological and molecular-genetic properties of strains - cau- sative agents of cholera - isolated in the period of epidemics in Ukraine in 1994 - 2011.

MATERIALS AND METHODS

Phenotypic and molecular-genetic properties of 5 strains of cholera vibrios, biovar El Tor isolated from cholera patients and 4 strains from the environmental samples were studied using traditional bacteriological and genetic methods. Detection of DNA for toxigenicity genes and genes characteristic for El Tor and classic biovar were carried out by PCR method using rea- gent kits <<AmpliSens- Vibrio cholerae FRT>> and <<Vibrio cholerae ctxB-rstR-rstC genes, REF>> an experimental test system). Sequencing of genomes of 4 strains of causative agents of cholera was carried out in genetic analyzer Ion Torrent Personal Genome Machine.

RESULTS

Strains of cholera vibrios identified in Ukraine in 1994 and 2011 such as a typical toxigenic biovar El Tor (V cholerae Ο1, El Tor, Ogawa, Hly-, ctxA+, tcpA+) contain genes ofthe classic cholera vibrio in their genome and are genetically altered (hybrid) variants of cholera vibrio biovar El Tor producing enterotoxin CTI and having increased virulence, that was clinically manifested in predominance of severe forms of cholera in Mariupol of Donetsk region in 2011. Genome sequences ofthe 4 studied strains were deposited into the international database DDBJ/EMBL/GenBank.

CONCLUSION

The studied isolates were established to belong to a clade of strains associated with cholera outbreaks in Haiti and Asian continent, from where genetically altered strains of cholera vibrios biovar El Tor were introduced to Haiti in 2010, based on results of comparison of genomic sequences of the studied strains with genomes of V cholera strains from the international database GenBank.

[New single nucleotide polymorphisms of androgen receptor gene (AR) in the Russian breed of Dzhalginsky Merino sheep]

This paper investigates the structure of androgen receptor gene (AR) in the Russian breed of Dzhalginsky Merino sheep. Polymorphisms of the gene were detected using NimbleGen sequencing technology (Roche, United States). Eight single nucleotide polymorphisms (SNPs) and two insertions were detected. Five of these SNPs (c.335T>G, c.339G>A, c.342T>C, c.2491-327T>A, and c.2491-325A>T) and both insertions were identified for the first time. Three SNPs and the insertions are located in the coding part of exon. Insertion c.336_337 is found in most of the animals of this breed and can be used as a genomic marker of the breed. Animals with mutant variant of SNP c.1496+15T>C have significantly lower live weight and body size compared with the wild type genotype. This SNP can be used as a genetic marker of meat production in marker-assisted selection.

[FEATURES OF MASS-SPECTROMETRIC PROTEIN PROFILES OF STRAINS OF BRUCELLOSIS CAUSATIVE AGENT DURING PREPARATION OF CULTURE ON VARIOUS NUTRIENT MEDIA]

AIM

Carry out comparative analysis using time-of-flight mass-spectrometry with matrix laser desorption/ionization (MALDI-TOF MS) of protein profiles of brucellosis causative agents (Brucella melitensis Rev-1 and Brucella abortus 19BA), cultivated in various nutrient media: Albimi agar, brucellagar and erythrit-agar.

MATERIALS AND METHODS

Vaccine,strains: Brucella melitensis Rev-1 and Brucella abortus 19BA. Protein profiling in linear mode on Microflex "Bruker Daltonics" MALDI-TOF mass-spectrometer.

RESULTS

A number of characteristic features of brucella mass-spectra was detected: in particular, preservation of the total qualitative composition of protein profiles of cultures and significant differences in the intensity of separate peaks depending on the nutrient medium used.

CONCLUSION

Based on the analysis of the data obtained, use of Albimi agar as the nutrient medium for preparation of brucella culture samples for mass-spectrometric analysis was shown to be optimal.

[Improvement of laboratory diagnostics of cholera due to genetically altered (hybrid) variants of cholera Vibrio biovar El Tor]

AIM

Improvement of laboratory diagnostics of cholera taking into the account appearance of hybrid variants of cholera vibrio El Tor biovar in the 1990s.

MATERIALS AND METHODS

Phenotypic and molecular-genetic properties of typical toxigenic (151 strains) and hybrid (102 strains) variants of El Tor biovar cholera vibrios, isolated in the Caucuses in 1970-1990 and 1993-1998, respectively, were studied. Toxigenicity gene DNA fragments, inherent to El Tor biovars or classic, were detected by using a reagent kit "Genes of Vibrio cholerae variant ctxB-rstR-rstC, REF" developed by us.

RESULTS

Reagent kit "Genes of V. cholerae variant ctxB-rstR-rstC, REF" is proposed to be used for laboratory diagnostics of cholera during study of material from humans or environmental objects and for identification of V. cholerae 01 on genome level in PCR-analysis as a necessary addition to the classic scheme of bacteriological analysis.

CONCLUSION

Laboratory diagnostics of cholera due to genetically altered (hybrid) variants of cholera vibrio El Tor biovar is based on a complex study of material from humans and environmental objects by routine bacteriologic and PCR-analysis methods with the aim of detection of gene DNA fragments in the studied material, that determine biovar (classic or El Tor), identification of V. cholerae O1 strains with differentiation of El Tor vibrios into typical and altered, as well as determination of enterotoxin, produced by the specific cholera vibrio strain (by the presence ctxB(El) or ctxB(Cl) gene DNA fragment, coding biosynthesis of CT-2 or CT-1, respectively).

[Comparative study of pharmacokinetics of ofloxacin in a free and niosomal forms in experiments on white mice when administered per os]

AIM

To study features of pharmacokinetics of ofloxacin as a part of anion PEGylated niosomes on a basis of sorbitan monostearate (Span 60) to experimental white mice per os.

MATERIALS AND METHODS

Ofloxacin was entrapped in niosomes consisting of Span 60, cholesterol, PEG 4000 and dicetylphosphate. Sizes of niosomes estimated by means of probe microscopy. Efficiency of inclusion of an antibiotic in niosomes defined after removal of free drug by a centrifugation. The analysis of the quantitative contents of ofloxacin in samples carried out a method of a high performance liquid chromatography.

RESULTS

We studied the main pharmacokinetic parameters of ofloxacin when used free and niosomal forms of antibiotic to experimental white mice per os. It is shown that use of oral niosomal forms leads to decrease of maximal concentration in serum and increase of ofloxacin half-life by 7,4 times in average compared to the free form. It is determined that bioavailability of ofloxacin in the niosomal form is 154% relative to the free form of the antibiotic.

CONCLUSIONS

Niosomal microcontainers are perspective technology of encapsulation and the directe transport of antibacterial preparations through biological barriers. Using of niosomal formulation of ofloxacin is able to afford to increase considerably efficiency of treatment in comparison with a free form and significantly decrease negative effects of antibiotic therapy.

[Use of multiple locus variable number tandem repeats analysis for the Brucella systematization]

The methods of molecular-genetic differentiation to strain level acquire increasing significance in the current system of struggle with brucellosis. MLVA (multiple locus variable number tandem repeats analysis) was selected for molecular-genetic differentiation to strain level and simultaneous establishment of the genetic relationship of investigated Brucella strains. The goal of this work was MLVA typing of three pathogenic Brucella species strains with the analysis of stability of chosen loci, discrimination power and concordance to conventional phenotypic methods of the Brucella differentiation for use in systematization of brucellosis causing agents.

MATERIALS AND METHODS

Twenty six Brucella strains representing reference (n = 15), vaccine (n = 2) and field strains of three pathogenic Brucella species were tested: B. melitensis (n = 3), B. abortus (n = 2), B. suis (n = 2), and isolates (n = 2) with unidentified taxonomic position using MLVA with 9 pairs primers on known variable loci of Brucella genome. The analysis of the stability of chosen loci, discrimination power on Hunter-Gaston discrimination index (HGDI) and consistency to phenotypic methods of identification was performed.

RESULTS

MLVA was confirmed for the results of phenotypic methods of identification, stability of the chosen loci in majority reference, and vaccine strains with a high index of variability HGDI 0.9969 for all loci. A dendrogram was plotted on the basis of MLVA data on distributed Brucella strains in related clusters according to its taxonomic species and biovar positions and construction of 25 genotypes. B. melitensis strains formed cluster related to the reference strain of B. melitensis 63/9 biovar 2. Australian isolates of Brucella 83-4 and Brucella 83-6 isolated from rodents formed a cluster distant from other strains of Brucella.

CONCLUSION

MLVA is a promising method for differentiation of Brucella strains with known and unresolved taxonomic status for their systematization and creation of MLVA genotype catalogue that will promote qualitative improvement of brucellosis surveillance system in Russia.