15 research outputs found
Неинвазивная оценка кровотока в левой коронарной артерии во время физической нагрузки. Трехлетний прогноз
Assessment of coronary flow is used during pharmacological tests. Nevertheless, supine bicycle tests have allowed the application of coronary flow assessments during exercise. The aim of the study was to define the outcomes of the consecutive cohort in three years period after coronary artery flow velocity analysis during exercise tests. Materials and methods. There is a single center prospective cohort study of 299 patients who underwent a bicycle exercise echocardiography with the analysis of coronary artery flow velocity in left anterior coronary artery (LAD). Coronary flow velocities were measured before and at the peak of exercise at the medium segment of the LAD. In addition, the coronary flow velocity reserve (CFVR) and the differences between the peak and rest velocities (ΔV) were calculated. Two hundred and fifty-nine patients were accessible for follow-up analysis (56 ± 9 years, 167 men). Cardiovascular death, nonfatal myocardial infarction, revascularization or cardiac arrests with cardiopulmonary resuscitation were defined as major adverse cardiac events (MACE). The period after stress test was 3.0 ± 0.1 years. Results. There were 77 patients with MACE. The group with MACE vs the rest patients had a lower velocity in LAD at the peak of exercise (58 ± 30 vs 68 ± 26 cm/s, p 2.1% had myocardial infarction, death or coronary artery bypass grafting in 3-year period. The group with CFVR ≤ 2 had МАСЕ in 40% of cases (p 2 1% пациентов имели неблагоприятные исходы, тогда как группа с КР ≤ 2 достигала конечных точек в 40% (р < 0,000001). Выводы. Анализ коронарного кровотока в ПМЖА на пике нагрузке может использоваться для определения трехлетнего прогноза
BRCA1 4153delA founder mutation in Russian ovarian cancer patients
The BRCA1 4153delA allele is frequently referred to as the Russian founder mutation, as it was initially detected in several cancer families from Moscow. Our earlier studies have demonstrated 1% occurrence of BRCA1 4153delA heterozygosity in familial and/or early-onset and/or bilateral Russian breast cancer (BC) patients. Since literature data suggest that the 4153delA variant is more associated with ovarian cancer (OC) than with BC, we expected to reveal a highly elevated frequency of this genotype in Russian ovarian cancer series. However, real-time allele-specific PCR genotyping has detected only two BRCA1 4153delA carriers out of 177 unselected OC patients (1.1%). Both these carriers were early-onset and had serous carcinomas of grade 3. Thus, our study supports neither the Russian origin of BRCA1 4153delA mutation, nor its selectivity towards ovarian versus breast cancer predisposition
CHEK2 1100 delC mutation in Russian ovarian cancer patients
BRCA1 and BRCA2 germ-line mutations occur in a significant number of unselected ovarian cancer (OC) patients, thus making a noticeable contribution to OC morbidity. It is of interest whether CHEK2, which is frequently regarded as a third breast cancer specific gene, is also relevant to ovarian cancer pathogenesis. In this report we analyzed the presence of CHEK2 1100 delC founder mutation in 268 randomly recruited OC patients. The mutation was identified in 2 women with OC (0.8%) as compared to 1/448 (0.2%) healthy middle-aged and 0/373 elderly tumour-free women. Taken together this result and the negative findings of two other published reports on an association of CHEK2 with ovarian cancer indicate that there is no justification for intensive ovarian cancer screening in CHEK2 1100 delC carriers
High frequency of BRCA1, but not CHEK2 or NBS1 (NBN), founder mutations in Russian ovarian cancer patients
<p>Abstract</p> <p>Background</p> <p>A significant portion of ovarian cancer (OC) cases is caused by germ-line mutations in BRCA1 or BRCA2 genes. BRCA testing is cheap in populations with founder effect and therefore recommended for all patients with OC diagnosis. Recurrent mutations constitute the vast majority of BRCA defects in Russia, however their impact in OC morbidity has not been yet systematically studied. Furthermore, Russian population is characterized by a relatively high frequency of CHEK2 and NBS1 (NBN) heterozygotes, but it remains unclear whether these two genes contribute to the OC risk.</p> <p>Methods</p> <p>The study included 354 OC patients from 2 distinct, geographically remote regions (290 from North-Western Russia (St.-Petersburg) and 64 from the south of the country (Krasnodar)). DNA samples were tested by allele-specific PCR for the presence of 8 founder mutations (BRCA1 5382insC, BRCA1 4153delA, BRCA1 185delAG, BRCA1 300T>G, BRCA2 6174delT, CHEK2 1100delC, CHEK2 IVS2+1G>A, NBS1 657del5). In addition, literature data on the occurrence of BRCA1, BRCA2, CHEK2 and NBS1 mutations in non-selected ovarian cancer patients were reviewed.</p> <p>Results</p> <p>BRCA1 5382insC allele was detected in 28/290 (9.7%) OC cases from the North-West and 11/64 (17.2%) OC patients from the South of Russia. In addition, 4 BRCA1 185delAG, 2 BRCA1 4153delA, 1 BRCA2 6174delT, 2 CHEK2 1100delC and 1 NBS1 657del5 mutation were detected. 1 patient from Krasnodar was heterozygous for both BRCA1 5382insC and NBS1 657del5 variants.</p> <p>Conclusion</p> <p>Founder BRCA1 mutations, especially BRCA1 5382insC variant, are responsible for substantial share of OC morbidity in Russia, therefore DNA testing has to be considered for every OC patient of Russian origin. Taken together with literature data, this study does not support the contribution of CHEK2 in OC risk, while the role of NBS1 heterozygosity may require further clarification.</p
The formation of the quality parameters of the surface layer by ultrasonic
In work the questions of hardening of a surface layer of a detail by means of ultrasonic fluctuations are opened. The developed device for forming ultrasonic longitudinal-torsional oscillations is described, which makes it possible to substantially modify the properties of the surface layers of the parts
Pilot study of the influence of a communicator’s speech characteristics on a recipient’s willingness to maintain interaction in cross-cultural online communication
The success of cross-cultural online communication in an academic environment is defined by the degree of student involvement in such an interaction. The authors’ experience testifies that a number of objective, language, and psychological factors may decrease the activeness of these interactions, and as a result learning may not be effective for students in these types of cross-cultural interactions. Among such factors the current article investigates the influence of a communicator’s speech peculiarities on a recipient’s willingness to maintain interaction in native-to-nonnative, written online communication in the English language. The study was aimed at verifying a hypothesis about the influence of Russian communicants’ speech characteristics on American communicants’ willingness to maintain conversations. The research method chosen was content analysis. Thematic chats involving Russian and American students participating in the Global Understanding course were analyzed. The results of the content analysis allowed us to distinguish certain Russian communicants’ written speech characteristics, such as the prevalence of language and grammar mistakes, the degree of vocabulary richness, and the use of complex sentences. Significant correlations were discovered between the American communicants’ willingness to maintain conversations and the number of mistakes, indicators of lexical richness and scarcity in Russian communicants’ utterances. Language and speech mistakes as well as the quantity of words in the utterances of micro themes had the highest number of significant correlations with indicators of the willingness to maintain conversations. The first factor, language and speech mistakes, decreased the willingness to maintain conversations, whereas the second factor, the number of words in Russian students’ utterances, increased such willingness
Challenges and Opportunities for Russian Higher Education amid COVID-19: Teachers’ Perspective
The COVID-19 pandemic has tremendously affected higher education systems in Russia and all over the world, forcing to transform curriculum into an online format, which is a challenge for all the educational process participants. The current study discusses the implementation of online learning amid the COVID-19 pandemic in the Russian higher education context and investigates the challenges experienced by university teachers during this period to define their readiness for online education. To address the above-mentioned issues, a study was conducted in Peter the Great St. Petersburg Polytechnic University. A variety of methods of scientific and pedagogical research were used including systematic structural analysis, synthesis, work with research papers, the generalization of experience and experimental work, observation, surveys, etc., with 87 university teachers asked to respond to several sets of questions describing their online teaching experience after the launch of online education amid the COVID-19 pandemic. The analysis of the participants’ answers helped to identify the following main challenges experienced by university teachers: computer literacy level, the university electronic environment and support, academic staff readiness and students’ readiness for online learning, the last two being the most important hindering the implementation of the efficient online education process. It was also underlined by most respondents that methodological work of a teacher in a digital educational environment differs from conventional teaching methods. Thus, psychological, technological, methodological support and teachers’ professional development programs are of vital importance to minimize the negative impact of the rapid changes of the educational process and to ensure efficient online education
Characterization of resistance to \u3ci\u3eSynchytrium endobioticum\u3c/i\u3e in cultivated potato accessions from the collection of Vavilov Institute of Plant Industry
The causal agent of potato wart (Synchytrium endobioticum) is an obligate parasitic chytrid fungus. It is included as a quarantine pathogen in 55 countries, with losses in susceptible cultivars reaching 50–100%. The aim of our study was to characterize the resistance to S. endobioticum pathotype 1 in cultivated potatoes from a well characterized subset of the Vavilov Institute of Plant Industry collection and to determine whether this resistance is associated with cultivated potato species taxonomy, with ploidy, with geographic distance or with a molecular marker Nl25-1400 proposed for molecular screening for resistance to pathotype 1 of S. endobioticum. Within the diversity of 52 landrace genotypes, our work shows a lack of such predictive associations with wart resistance. High intraspecific variation of wart diseases resistance allows the selection of extremely resistant and susceptible genotypes available for future genetic and breeding studies