ANALYSIS OF EPIDEMIOLOGICAL FEATURES OF THE INCIDENCE OF DIPHYLLOBOTHRIASIS IN SIBERIAN FEDERAL DISTRICT AND IRKUTSK REGION

The article presents the comparative analysis of the incidence of diphyllobothriasis in the Siberian Federal District and the Irkutsk  Region, and the peculiarities of its epidemiology in the Irkutsk  Region. On the basis of in-depth study of the structure of  diphyllobothriasis foci functioning on the territory of Irkutsk Region,  the zoning of the territory was carried out according to the degree of risk of contamination with diphyllobothriidae. The categories of the  population of various age groups exposed to invasion is defined, and  dynamics of morbidity within groups is analyzed. The analysis  revealed a distinctive feature of the Irkutsk Region, which is  expressed in a greater proportion of children among the sick people compared to other regions of the Siberian Federal District and the lowest incidence reduction rates among this group. The question  of reorientation of preventive and explanatory work with the  population, taking into account the identified data, is raised. The  cases are also considered on the basis of belonging to the rural or  urban population; among the rural population, the incidence is  almost twice as high. The analysis of morbidity in some territories of  the Irkutsk Region was carried out on the basis of an integral  indicator, which was carried out by ranking individual territories  according to the degree of infection of the population, areas with low, medium, high and very high levels of morbidity were allocated

Design of organyl phosphate-based pro-drugs: comparative analysis of the antibiotic action of alkyl protecting groups with different degree of fluorination

Background. Molecular structures combining a phosphorus-containing counterpart and non-polar radicals are employed in design of pro-drugs as structural and functional groups necessary for transportation of drugs through cellular barriers. It is assumed that the carrier itself does not exhibit biological activity. However, the “organic phosphate – alkyl radical” complex may possess its own metabolic and pharmacological properties even in the absence of a drug moiety.The aim. To study the effect of fluorinated alkyl phosphates on the growth of bacterial test cultures in an agar medium and to identify conjugated metabolic markers using UV/visible spectroscopy.Materials and methods. The effect of six organyl phosphates on the growth of five types of bacteria under aerobic conditions was evaluated by the method of wells in an agar medium. For solutions containing cell metabolites of Pseudomonas aeruginosa, the absorption spectra were recorded at 250–280 nm. The principal component analysis (PCA) was used for multivariate comparative analysis of the spectra. Results. The studied organyl phosphates bearing the ethyl and propyl radicals are potential temporary carriers of the drug moiety, since they are capable of penetrating through cellular barriers. However, the fluorinated compounds exhibit bactericidal properties, the degree of which depends on the arrangement of fluorine atoms in the radical. The most active compounds are those exhaustively halogenated at the terminal carbon atom of the ethyl radical (-СН2-СF3), while non-fluorinated organyl phosphate is the least active. UV/visible spectra of P. aeruginosa cultivation products, according to PCA data, contain patterns reflecting the metabolic effects mediated by these structural features of the radicals.Conclusion. In terms of practical application of the studied compounds, the activity of a proantibiotic based on organyl phosphate with a non-fluorinated ethyl(propyl) radical will be determined only by the specificity of the drug moiety. Exactly the same molecule, but exhaustively fluorinated at the terminal carbon atom of the alkyl radical, is likely to be characterized by lower specificity and higher activity under the additive (or synergistic) action of metabolically active groups

BIOINFORMATIC SEARCH OF CRISPR/CAS SYSTEM STRUCTURES IN GENOME OF PCT281 PLASMID OF BACILLUS THURINGIENSIS SUBSP. CHINENSIS STRAIN CT-43

Background. CRISPR/Cas systems loci are one of the functionally important patterns in bacterial genome which perform the role of “adaptive immune defense” from foreign nucleic acids. The study of CRISPR/Cas systems structure in genomes of plasmids and phages provide new information about the evolution of this systems in bacterial hosts.Aims. A search of CRISPR/Cas systems structures in pCT281 plasmid from Bacillus thuringiensis subsp. chinensis strain CT-43 using bioinformatic methods.Materials and methods. Search studies using bioinformatics methods were performed with the genome of pCT281 plasmid of B. thuringiensis subsp. chinensis strain CT-43 from the RefSeq database. To search for the CRISPR/Cas system structure MacSyFinder (ver. 1.0.5) and three combined algorithms were used: CRISPRFinder; PILER-CR; CRISPR Recognition Tool (CRT). The consensus repeat sequence was generated in WebLogo 3.Results and discussion. In pCT281 plasmid we detected one locus of CRISPR/Cas system of the type I-C which contains 2 CRISPR-cassettes and 4 cas-genes located between them. The CRISPR-cassette 1 includes 10 spacers from 32 to 35 bp and 11 repeats 32bp in length. 5 spacers (33–35 bp) separated by 6 repeats 32 bp in length were detected in the CRISPR-cassette 2.Conclusions. The bioinformatic methods used in this study enable to conduct a search of CRISPR/Cas systems structures in plasmid genomes. The presence of the CRISPR-Cas locus in pCT281 plasmid confirms a possible transfer of this system from the nucleoid to this plasmid. The detected spacers provide information about phages this bacteria was encountered

Surgical Treatment of Bullous Keratopathy: Modern Approaches and Trends

According to WHO, corneal pathology is the fourth cause (5.1 %) of blindness among the main causes of significant visual impairment in the world after cataract, glaucoma and macular degeneration. Bullous keratopathy is a serious progressive corneal disease, in which the endothelial lesion plays the main role leading to the chronic corneal edema, reduce of visual acuity, development of pain syndrome, formation of permanent opacities, and various infectious complication, which may result in eye globe loss. Since the second half of 90th XX century various modifications of modern posterior (endothelial) keratoplasty have been introduced in the clinical practice, which were subsequently used widely for the treatment of bullous keratopathy. The introduction of new microkeratomes used in refractive surgery significantly contributed to the development of endothelial keratoplasty microsurgical technique, which enables the high quality, selective replacement of the affected corneal layers in comparison to the manual lamellar keratoplasty techniques. One of the contraindications for endothelial keratoplasty is an irreversible central stromal opacity. In that case, modern technologies and new equipment (particularly femtosecond laser) provide an opportunity to perform the penetrating keratoplasty with a complex-shaped profile and corresponding edges of the graft and its bed. In bullous keratopathy, top-hat keratoplasty represents the pathogenically targeted treatment method that allows transplanting of more endothelial cells with a relatively smaller diameter of graft’s anterior segment. This article reviews the literature on modern surgical treatment of bullous keratopathy

CORNEAL GRAFT REJECTION AFTER KERATOPLASTY

Corneal transplantation is a method of surgical treatment used to restore the optical and structural properties of the diseased cornea which is successfully performed for over 100 years. The immune rejection remains one of the most common causes of an unsatisfactory outcomes of penetrating keratoplasty. The cases of corneal allograft rejection range from 2.3% to 65% depending on the risk factors taking place in the recipient. The most well-known risk factors for corneal allograft rejection are neovascularization of the recipient’s cornea, active ocular inflammation, herpetic keratitis, ocular surface disease, young age, previous surgery of the anterior segment of the eye, neurotrophic keratopathy, big and eccentric graft, anterior synechia. Given the fact that the pathophysiology of corneal graft rejection is very complex and not fully understood the applied methods of treatment and prevention are often ineffective in “high risk” patients. New experimental targeted approaches including the use of antibodies and gene therapy are currently being developed but do not have a clear success in the clinic yet.Therefore for obtaining satisfactory outcomes of corneal transplantation in “high risk” patients all main known risk factors have to be taken into account with subsequent possible preoperative therapy to reduce their impact; careful monitoring of the patient in the postoperative period should be done to early detection of allograft rejection signs; optimal schemes and combinations of immunosuppressive drugs authorized for use in the clinic have to be developed