Preventive Tuberculosis Services Reduces the Risk of Local Forms of Tuberculosis Development in Children on Immunosuppressive Therapy: Retrospective Cohort Study

Background. Long-term immunosuppressive therapy in children (including genetically engineered biologic drugs, GEBD) is associated with a high risk of local tuberculosis (TB) development. Objective. The aim of the study was to examine efficacy of tuberculosis services in children with high risk of developing tuberculosis associated with immunosuppressive therapy.Methods. The study included children at the age from 0 to 17 years on immunosuppressive therapy due to autoimmune disease and who were referred to phthisiatrician consultation. The incidence of TB was estimated one year after in groups receiving preventive TB services (isoniazid and pyrazinamide for 3–6 months) due to the high risk of TB development (contact with TB patients and/or controversial or positive test results with tubercular recombinant allergen) or not receiving such therapy (no indications for preventive treatment, parents’ refusal). The source of any data was medical documentation.Results. Preventive tuberculosis service was performed in 167 (60%) out of 279 children included in the study, 112 children did not receive such treatment (5 cases — parents’ refusal, 107 cases — lack of indications for preventive treatment). TB was detected in 1 (0.6%) child after one year in the preventive treatment group, and in 14 (12.5%) children (p < 0.001) in the group without preventive treatment. Thoracic lymph nodes tuberculosis was diagnosed in 4 (27%) patients among all who has developed TB, tuberculous primary complex — in 3 (20%) patients, focal tuberculosis in 7 (46%) patients, disseminated tuberculosis in 1 (7%) patient.Conclusion. Preventive tuberculosis service reduces the risk of tuberculosis in children on administration of immunosuppressive drugs, including GEBD

The difference between cellulolytic 'culturomes' and microbiomes inhabiting two contrasting soil types.

High-throughput 16S rRNA sequencing was performed to compare the microbiomes inhabiting two contrasting soil types-sod-podzolic soil and chernozem-and the corresponding culturome communities of potentially cellulolytic bacteria cultured on standard Hutchinson media. For each soil type, soil-specific microorganisms have been identified: for sod-podzolic soil-Acidothermus, Devosia, Phenylobacterium and Tumebacillus, and for chernozem soil-Sphingomonas, Bacillus and Blastococcus. The dynamics of differences between soil types for bulk soil samples and culturomes varied depending on the taxonomic level of the corresponding phylotypes. At high taxonomic levels, the number of common taxa between soil types increased more slowly for bulk soil than for culturome. Differences between soil-specific phylotypes were detected in bulk soil at a low taxonomic level (genus, species). A total of 13 phylotypes were represented both in soil and in culturome. No relationship was shown between the abundance of these phylotypes in soil and culturome

Rhizobia Isolated from the Relict Legume Vavilovia formosa Represent a Genetically Specific Group within Rhizobium leguminosarum biovar viciae

Twenty-two rhizobia strains isolated from three distinct populations (North Ossetia, Dagestan, and Armenia) of a relict legume Vavilovia formosa were analysed to determine their position within Rhizobium leguminosarum biovar viciae (Rlv). These bacteria are described as symbionts of four plant genera Pisum, Vicia, Lathyrus, and Lens from the Fabeae tribe, of which Vavilovia is considered to be closest to its last common ancestor (LCA). In contrast to biovar viciae, bacteria from Rhizobium leguminosarum biovar trifolii (Rlt) inoculate plants from the Trifolieae tribe. Comparison of house-keeping (hkg: 16S rRNA, glnII, gltA, and dnaK) and symbiotic (sym: nodA, nodC, nodD, and nifH) genes of the symbionts of V. formosa with those of other Rlv and Rlt strains reveals a significant group separation, which was most pronounced for sym genes. A remarkable feature of the strains isolated from V. formosa was the presence of the nodX gene, which was commonly found in Rlv strains isolated from Afghanistan pea genotypes. Tube testing of different strains on nine plant species, including all genera from the Fabeae tribe, demonstrated that the strains from V. formosa nodulated the same cross inoculation group as the other Rlv strains. Comparison of nucleotide similarity in sym genes suggested that their diversification within sym-biotypes of Rlv was elicited by host plants. Contrariwise, that of hkg genes could be caused by either local adaptation to soil niches or by genetic drift. Long-term ecological isolation, genetic separation, and the ancestral position of V. formosa suggested that symbionts of V. formosa could be responsible for preserving ancestral genotypes of the Rlv biovar

Photocurable Methacrylate Derivatives of Polylactide: A Two-Stage Synthesis in Supercritical Carbon Dioxide and 3D Laser Structuring

A two-stage polylactide modification was performed in the supercritical carbon dioxide medium using the urethane formation reaction. The modification resulted in the synthesis of polymerizable methacrylate derivatives of polylactide for application in the spatial 3D structuring by laser stereolithography. The use of the supercritical carbon dioxide medium allowed us to obtain for the first time polymerizable oligomer-polymer systems in the form of dry powders convenient for further application in the preparation of polymer compositions for photocuring. The photocuring of the modified polymers was performed by laser stereolithography and two-photon crosslinking. Using nanoindentation, we found that Young’s modulus of the cured compositions corresponded to the standard characteristics of implants applied in regenerative medicine. As shown by thermogravimetric analysis, the degree of crosslinking and, hence, the local stiffness of scaffolds were determined by the amount of the crosslinking agent and the photocuring regime. No cytotoxicity was observed for the structures