Хирургическое лечение атеросклеротического стеноза сонных артерий в сочетании с патологической извитостью внутренней сонной артерии с целью профилактики ишемического инсульта

АРТЕРИОСКЛЕРОЗКОРОНАРОСКЛЕРОЗСОННЫЕ АРТЕРИИ /хирИНСУЛЬТ ЦЕРЕБРОВАСКУЛЯРНЫЙкинкингкойлингстеноз аортальныйхирургические вмешательствапатологическая извитост

Результаты симультанных операций у пациентов с атеросклеротическим поражением сонных и коронарных артерий

СОННЫЕ АРТЕРИИАТЕРОСКЛЕРОЗАРТЕРИОСКЛЕРОЗКОРОНАРНЫХ АРТЕРИЙ СТЕНОЗКАРОТИДНАЯ ЭНДАРТЕРЭКТОМИЯСОННОЙ АРТЕРИИ ЭНДАРТЕРЭКТОМИЯСТЕНОКАРДИЯАОРТОКОРОНАРНОЕ ШУНТИРОВАНИЕКОРОНАРНОЙ АРТЕРИИ ШУНТИРОВАНИ

Ways to improve the social efficiency of small and medium-sized businesses in the context of digitalization

This article discusses the issue related to ways to improve the social efficiency of small and medium-sized businesses in the context of digitalization. The authors consider key aspects concerning the internal component of business processes through the prism of a behaviorist approach – study the role of human capital in the formation of social efficiency of the company, identify ways of measuring it and the role of job satisfaction, as well as the impact of this indicator on the productivity of the workforce as a whole. The social efficiency of a company is a complex phenomenon, therefore, the study of ways to improve it through internal business processes is important. As the main conclusions to the work, the authors formulate recommendations for improving the level of job satisfaction through the integration of the latest digital technologies. An important place in this article is devoted to the study of the issue related to the factors of increasing job satisfaction. The authors consider the main groups of factors that form the level of employee satisfaction with work. Based on the identified factors, the authors make recommendations to improve the social efficiency of the company. In the final part of the article, the authors make conclusions regarding the further development of the social efficiency of small and medium-sized businesses in the conditions of digitalization

The BCL-2 pathway preserves mammalian genome integrity by eliminating recombination-defective oocytes

DNA double-strand breaks (DSBs) are toxic to mammalian cells. However, during meiosis, more than 200 DSBs are generated deliberately, to ensure reciprocal recombination and orderly segregation of homologous chromosomes. If left unrepaired, meiotic DSBs can cause aneuploidy in gametes and compromise viability in offspring. Oocytes in which DSBs persist are therefore eliminated by the DNA-damage checkpoint. Here we show that the DNA-damage checkpoint eliminates oocytes via the pro-apoptotic BCL-2 pathway members Puma, Noxa and Bax. Deletion of these factors prevents oocyte elimination in recombination-repair mutants, even when the abundance of unresolved DSBs is high. Remarkably, surviving oocytes can extrude a polar body and be fertilised, despite chaotic chromosome segregation at the first meiotic division. Our findings raise the possibility that allelic variants of the BCL-2 pathway could influence the risk of embryonic aneuploidy

The role of new genetic technologies for the analysis of early human embryos: clinical application and research

Mutations of the beta-globin gene (HBB) are the most common cause of inherited disease in humans, causing ß-thalassaemia and sickle cell anaemia. Traditional preimplantation genetic testing (PGT) protocols for the detection of HBB mutations frequently involve labour intensive, patient-specific test designs owing to the wide diversity of disease-associated HBB mutations. Chapter 1 focuses on the development, validation and clinical implementation of a novel and universally applicable PGT method for the diagnosis of HBB gene mutations, utilising next generation sequencing (NGS). Employing this protocol HBB mutation status and associated single nucleotide polymorphism (SNP) haplotypes were successfully determined in all 21 embryos of three couples undergoing PGT for ß-thalassaemia. Analysis of 141 heterozygous sites showed no instances of allele dropout in the clinical samples and the test displayed 100% concordance compared with the data obtained using an established method (karyomapping). Taken together, the results suggest that the new method may deliver superior accuracy than typically achieved with traditional PGT methods. Furthermore, the test is streamlined and economical, which should improve patient access to PGT, reducing costs and waiting times. This will be especially important in less affluent parts of the world where diseases affecting hemoglobin synthesis are of high prevalence. An alternative to PGT for reducing the burden of inherited disorders is the correction of disease-causing mutations in human embryos using genome editing methods. However, this possibility is subject to numerous ethical and technical concerns, especially as intervention in gametes or preimplantation embryos would inevitably involve modification of the germline and a high likelihood of transmission of edited genes to future generations. CRISPR-Cas9 is currently the leading technology for introducing specific and heritable modifications into the genome. Chapter 2 evaluated the CRISPR-Cas9 system from the perspective of technical feasibility. It involved development of a methodological framework and computational pipelines for evaluation of on-target mutagenesis as well as potential off-target consequences of the editing in OCT4 (POU5F1) CRISPR-Cas9-targeted human zygotes and controls. A high efficiency of editing was observed with a wide variety of indel mutations, characteristic of non-homologous end-joining (NHEJ). No evidence of off-target activity was recorded. There is a possibility of unintended editing outcomes following the use of CRISPR-Cas9 that may have pathologic consequences, potentially exacerbated by insufficient DNA repair in early human embryos prior to embryonic genome activation (EGA). Chapter 3 investigated the repair outcomes of Cas9-induced double-strand breaks (DSBs) introduced in the POU5F1 locus. Strikingly, the results showed that 37.5% of the targeted zygotes present with breaks that remain unrepaired or participate in complex genomic rearrangements, resulting in segmental aneuploidy with breakpoints within the targeted 6p21.3 region. Gains and losses of large regions, stretching from 6p21.3 to the end of the short arm of chromosome 6, as well evidence indicating a complexity of DNA sequence mutations at on-target sites after CRISPR-Cas9 editing, provide a cautionary note to those considering the technology for clinical use and underscore the importance of basic research into DNA repair pathways and genomic stability in human embryos. Such research is not only relevant in the context of genome editing, but also has importance for assisted reproductive treatments and stem cell research. Furthermore, collaborative work of which this thesis is a part emphasizes that CRISPR-Cas9 remains a powerful molecular biology tool for the study of gene function and the biology of early human development.</p

Clinical application of a protocol based on universal next-generation sequencing for the diagnosis of beta-thalassaemia and sickle cell anaemia in preimplantation embryos

Research question Mutations of the beta-globin gene (HBB) cause beta-thalassaemia and sickle cell anaemia and are the most common cause of severe inherited disease in humans. Traditional PGD protocols for the detection of HBB mutations frequently involve labour intensive, patient-specific test design due to the wide diversity of disease associated HBB mutations. For this reason, we aimed to develop and clinically apply a universal PGD method to test for mutations in the HBB gene. Design A multiplex PCR protocol was designed, allowing simultaneous amplification of multiple overlapping DNA fragments encompassing the entire HBB gene sequence in addition to 17 characterized, closely linked single nucleotide polymorphisms (SNPs). Amplicons were then analyzed using a next generation sequencing (NGS) method, revealing mutations and SNP genotypes. The protocol was extensively validated, optimized and eventually clinically applied on whole-genome amplified (WGA) DNA derived from embryos of three couples carrying different combinations of β-thalassemia mutations. Results The HBB mutation status and associated SNP haplotypes were successfully determined in all 21 embryos. Interestingly, analysis of 141 heterozygous sites showed no instances of allele dropout (ADO) and the test displayed 100% concordance when compared to the results obtained from karyomapping. This suggests that the combination of trophectoderm biopsy and highly sensitive NGS may provide superior accuracy than typically achieved using traditional PGD methods. Importantly, no patient-specific test design or optimization was needed. Conclusions It is hoped that protocols that deliver almost universally-applicable low-cost tests, without compromising diagnostic accuracy, will improve patient access to PGD, especially in less affluent parts of the world.</p

Clinical application of a protocol based on universal next-generation sequencing for the diagnosis of beta-thalassaemia and sickle cell anaemia in preimplantation embryos

Research question Mutations of the beta-globin gene (HBB) cause beta-thalassaemia and sickle cell anaemia and are the most common cause of severe inherited disease in humans. Traditional PGD protocols for the detection of HBB mutations frequently involve labour intensive, patient-specific test design due to the wide diversity of disease associated HBB mutations. For this reason, we aimed to develop and clinically apply a universal PGD method to test for mutations in the HBB gene. Design A multiplex PCR protocol was designed, allowing simultaneous amplification of multiple overlapping DNA fragments encompassing the entire HBB gene sequence in addition to 17 characterized, closely linked single nucleotide polymorphisms (SNPs). Amplicons were then analyzed using a next generation sequencing (NGS) method, revealing mutations and SNP genotypes. The protocol was extensively validated, optimized and eventually clinically applied on whole-genome amplified (WGA) DNA derived from embryos of three couples carrying different combinations of β-thalassemia mutations. Results The HBB mutation status and associated SNP haplotypes were successfully determined in all 21 embryos. Interestingly, analysis of 141 heterozygous sites showed no instances of allele dropout (ADO) and the test displayed 100% concordance when compared to the results obtained from karyomapping. This suggests that the combination of trophectoderm biopsy and highly sensitive NGS may provide superior accuracy than typically achieved using traditional PGD methods. Importantly, no patient-specific test design or optimization was needed. Conclusions It is hoped that protocols that deliver almost universally-applicable low-cost tests, without compromising diagnostic accuracy, will improve patient access to PGD, especially in less affluent parts of the world.</p

Differentiated approach to surgical treatment of atherosclerotic lesions of supra-aortic arteries

Atherosclerotic lesions of the supra-aortic arteries are mainly localized in the carotid artery bifurcations – 57%, the subclavian artery – 18%, the vertebral arteries – 14%, the brachiocephalic trunk and the common carotid artery – 11%.Objective. Theobjective of the research was to systematize the principles of surgical treatment of patients with atherosclerotic lesions of the supra-aortic arteries taking into consideration their polymorbidity and the multicentricity of atherosclerosis.Materials and methods. The results of surgical reconstruction of the supra-aortic arteries in 468 patients were analyzed.All the patients were divided into two groups.Group I included 276 (59%) patients with previous surgical or endovascular intervention on any vascular territory for treatment of atherosclerotic lesions being admitted to the hospital for elective surgery on the extracranial arteries.Group II included 192 (41%) patients without previous surgical and invasive treatments of arterial pathology being hospitalized for surgery on the supra-aortic arteries.Results. In Group I, according to the objective and clinical methods of examination, the patients’ condition was more critical due to somatic and intraoperative risk. When analyzing the results of postoperative complications there was no statistically significant difference between both groups (p&lt;0.05).The overall rate for serious complications (acute cerebrovascular disease and myocardial infarction) in both groups was 3.4%; the mortality rate was 1.1%.Conclusions. 1. Approximately 87% of surgical reconstructions of the aortic arch branches are aimed at the prevention of acute cerebrovascular disease. 2. Surgical treatment of atherosclerotic lesions of the supra-aortic arteries allows us to achieve good postoperative results (the overall rate for serious complications – 3.4%, the mortality rate –1.1%)

METODO DI GENERAZIONE DI MOTO ONDOSO IN UN CORPO LIQUIDO MEDIANTE ALMENO UNA PALA CUNEIFORME AVENTE PROFILO LATERALE DI GEOMETRIA CURVILINEA AZIONATA DA UN ATTUATORE LINEARE A SCORRIMENTO VERTICALE

METODO DI GENERAZIONE DI MOTO ONDOSO IN UN CORPO LIQUIDO MEDIANTE ALMENO UNA PALA CUNEIFORME AVENTE PROFILO LATERALE DI GEOMETRIA CURVILINEA AZIONATA DA UN ATTUATORE LINEARE A SCORRIMENTO VERTICAL