Haploid biotechnology as a tool for creating a selection material for sugar beets

Since the discovery of the phenomenon of haploidy, biotechnology has become an integral part in the successful creation of new varieties and hybrids of various plant species. In particular, these technologies are actively used in agriculture, which is concerned with increasing the volume and improving the quality of products. The integration of haploid production techniques together with other available biotechnological tools such as marker selection (MAS), induced mutagenesis and genetic engineering technologies can significantly accelerate crop breeding. This article shows the main stages in the development of biotechnology since 1921. Now they are successfully used to create doubled haploids to accelerate the selection process of various plants and, in particular, sugar beet, which is the most important sugar crop in regions with a temperate climate. There are several methods for obtaining forms with a single set of chromosomes. For sugar beets, the use of gynogenesis turned out to be expedient, since in this case the other methods turned out to be ineffective in the mass production of haploids. The article considers the stages of obtaining the H and DH lines of Beta vulgaris L., as well as the main stages of biotechnological production of homozygous breeding material of this culture. These stages include selecting parental forms – donor explants, sterilizing buds and introducing non-pollinated ovules in vitro, obtaining haploids, doubling their chromosome set, creating doubled haploids, determining ploidy at different stages, relocating the obtained plants to greenhouses and growing stecklings. A number of advantages that the technology of creating doubled haploids in vitro has in comparison with traditional methods of selection are described. It has been shown that the use of these approaches is relevant when obtaining new highly productive hybrids and varieties of agricultural plants; however, the methods for the production of homozygous forms in sugar beet still require additional research aimed at increasing the efficiency and reproducibility of each stage of the process

HYDROLYTIC STABILITY OF IMIDES OF DIFFERENT STRUCTURES

The conversion kinetics of N(o-carboxyphenyl)naphthalimide has been studied in buffer solutions over a pH range 5-12.6 and temperature range 25-70 °C. The naphthalimide hydrolysis is shown to be a reversible reaction. The mechanism of the alkaline hydrolysis of N(o- carboxyphenyl) phthalimide is proposed. The structure dependence of the imide hydrolytic stability is explained on the basis of the suggested mechanism

Structure of Population of Strains of the Bordetella pertussis in the Russia

Relevance. Despite more than 50 years of successful experience with pertussis immunization, pertussis remains an important public health problem. WHO estimated 16 million people worldwide are infected per year, a significant number of whom are children under 1 year of age. In the last 10 years a significant increase in the incidence of whooping cough has been observed in many countries with a high immunization coverage level. In Russia, specific prevention of whooping cough, is held since 1959. Specific prevention of whooping cough has led to considerable improvement of an epidemiological situation and has shown its social and economic importance for maintenance of sanitary and epidemiologic wellbeing on this infection in Russia. Goal. Study the structure of population B. pertussis circulating in Russia in dynamics of whooping cough epidemic process. Materials and methods Studied 573 B. pertussis strains allocated from patients with whooping cough in 1948 - 2015 used multilocus sequence typing (MAST). Isolates divided in five groups: 1948 - 1969 - 37 strains, isolated in the vaccination period and the first ten years of mass childhood immunization; 1970 - 1989 - 63 strains; 1990 - 2005 - 203 strains (from G.N. Gabrichevsky Institute of Epidemiology and Microbiology collection); 2006 - 2012 - 185 strains; 2013 - 2015 - 85 strains. Genotyping of strains was carried out according to the scheme MAST2 on the basis of a sequence of fragments of genes of ptxP-fim3-prn. Results of sequencing-typing were computed in the CromasLite program, identification of alleles and sequencing types carried out on EMBL/GenBank. Results. Formation of population of B.pertussis strains during more than 50 years went on the way of consecutive change of vaccinal genotype strains with strains of new nonvaccinal genotypes. Conclusions. Modern population of the causative agent of whooping cough is presented by the strains of genotype 322 and 329 possessing high virulence and causing heavier clinical course of disease

Post-neoadjuvant treatment of breast cancer

Achieving a pathologic complete response as a result of neoadjuvant treatment is associated with improved prognosis in breast cancer. The CREATE-X trial showed a significant survival improvement with capecitabine treatment of patients with residual invasive disease following neoadjuvant chemotherapy, and the KATHERINE trial demonstrated a significant benefit of trastuzumabemtansine (TDM1) in patients with HER2-positive breast cancer who did not achieve a pathologic complete response, so we have a lot of interesting alternatives of post-neoadjuvant treatments for high-risk patients. The discovery of molecular markers of resistance to endocrinotherapy (cyclin-dependent kinases (CDK 4/6), ER mutation (ESR1), mTOR signaling pathway, co-expression of ER+/HER2+) and inhibitors to them expanded the possibilities of endocrinotherapy not only in advanced and metastatic breast cancer, but also in residual ER+ tumors. The pCR rates in hormone receptor-positive breast cancer after neoadjuvant chemotherapy are around 10%, which is much lower than the values observed in HER2-positive and triple negative subtypes, so new strategies are needed to improve pCR rates in this subgroup, even though the adjuvant endocrine therapy impacts significantly the outcomes of this patients. The cyclin-dependent kinases (CDKs) are serine–threonine kinases that regulate cell cycle progression from the G1 to the S-phase during mitosis. CDKs activity can be abnormally increased or dysregulated in breast cancer, leading to a constant stimulus for cell proliferation and survival, which is a known mechanism of resistance to endocrine treatment. The CDK inhibitors act on CDKs and block their activity, thereby restoring the cell cycle regulation. In studies with metastatic hormone receptor-positive breast cancer patients, the combination of a CDKis with first or second-line endocrine therapy showed significant improvements in progression-free survival and response rates. Evolving techniques such as next-generation sequencing and gene expression profiles have improved our understanding of the biology of residual disease and also the mechanisms involved in treatment resistance