Elementary amenable subgroups of R. Thompson's group F

The subgroup structure of Thompson's group F is not yet fully understood. The group F is a subgroup of the group PL(I) of orientation preserving, piecewise linear self homeomorphisms of the unit interval and this larger group thus also has a poorly understood subgroup structure. It is reasonable to guess that F is the "only" subgroup of PL(I) that is not elementary amenable. In this paper, we explore the complexity of the elementary amenable subgroups of F in an attempt to understand the boundary between the elementary amenable subgroups and the non-elementary amenable. We construct an example of an elementary amenable subgroup up to class (height) omega squared, where omega is the first infinite ordinal.Comment: 20 page

Operator interpretation of resonances generated by some operator matrices

We consider the analytic continuation of the transfer function for a 2x2 matrix Hamiltonian into the unphysical sheets of the energy Riemann surface. We construct a family of non-selfadjoint operators which reproduce certain parts of the transfer-function spectrum including resonances situated on the unphysical sheets neighboring the physical sheet. On this basis, completeness and basis properties for the root vectors of the transfer function (including those for the resonances) are proved.Comment: LaTeX, 15 pages, no figures; Contribution to Proceedings of the Mark Krein International Conference on Operator Theory and Applications, Odessa, August 18-22, 199

Phenotypic heterogeneity and diagnostic features of transthyretin amyloidosis with polyneuropathy

Transthyretin amyloidosis (ATTR-amyloidosis) is a systemic progressive fatal disease, for which a modifying therapy has recently been proposed that delays the progression of the disease and improves the patient’s quality of life. The delay in the diagnosis of ATTR-amyloidosis is associated with the heterogeneity of the manifestations of the disease, as well as insufficient awareness of doctors of different specialties about the disease. A review of recent studies on the symptomatology, diagnosis, molecular genetic characteristics of ATTR-amyloidosis and the most common forms of the disease with the predominant involvement of peripheral nerves and the heart, as well as the kidneys, gastrointestinal tract, and eyes is presented. The international consensus recommendations for the diagnosis of suspected ATTR-amyloidosis using modern methods that facilitate early and accurate diagnosis are discussed. The reasons and the most frequent misdiagnoses of ATTR-amyloidosis, which also lead to a delay in the timely appointment of therapy, are considered. Molecular genetic testing should be considered early in the evaluation of a patient with unexplained peripheral neuropathy and cardiomyopathy. A diagnostic algorithm based on the initial symptoms and manifestations of the cardiovascular and nervous systems facilitates the identification of a patient with clinical suspicion of ATTR-amyloidosis by the general practitioner. Early diagnosis is critically important for patients with ATTR polyneuropathy, since the early prescription of Vyndaqel (tafamidis), registered in the Russian Federation in 2017, allows a significant clinical effect to be obtained. Timely administration of Vyndaqel significantly slows down the progression of the disease, improves the prognosis and quality of life in patients with ATTR polyneuropathy

Фенотипическая гетерогенность и особенности диагностики транстиретинового амилоидоза с полинейропатией

Transthyretin amyloidosis (ATTR-amyloidosis) is a systemic progressive fatal disease, for which a modifying therapy has recently been proposed that delays the progression of the disease and improves the patient’s quality of life. The delay in the diagnosis of ATTR-amyloidosis is associated with the heterogeneity of the manifestations of the disease, as well as insufficient awareness of doctors of different specialties about the disease. A review of recent studies on the symptomatology, diagnosis, molecular genetic characteristics of ATTR-amyloidosis and the most common forms of the disease with the predominant involvement of peripheral nerves and the heart, as well as the kidneys, gastrointestinal tract, and eyes is presented. The international consensus recommendations for the diagnosis of suspected ATTR-amyloidosis using modern methods that facilitate early and accurate diagnosis are discussed. The reasons and the most frequent misdiagnoses of ATTR-amyloidosis, which also lead to a delay in the timely appointment of therapy, are considered. Molecular genetic testing should be considered early in the evaluation of a patient with unexplained peripheral neuropathy and cardiomyopathy. A diagnostic algorithm based on the initial symptoms and manifestations of the cardiovascular and nervous systems facilitates the identification of a patient with clinical suspicion of ATTR-amyloidosis by the general practitioner. Early diagnosis is critically important for patients with ATTR polyneuropathy, since the early prescription of Vyndaqel (tafamidis), registered in the Russian Federation in 2017, allows a significant clinical effect to be obtained. Timely administration of Vyndaqel significantly slows down the progression of the disease, improves the prognosis and quality of life in patients with ATTR polyneuropathy.Транстиретиновый амилоидоз (ATTR-амилоидоз) – системное прогрессирующее фатальное заболевание, для которого в последнее время предложена модифицирующая терапия, задерживающая прогрессирование болезни и улучшающая качество жизни пациента. Задержка диагностики ATTR-амилоидоза связана с неоднородностью проявлений болезни, а также с недостаточной информированностью врачей разных специальностей о заболевании. Представлен обзор последних исследований по симптоматике, диагностике, молекулярно-генетическим характеристикам ATTR-амилоидоза и самых частых форм болезни с преимущественным вовлечением периферических нервов и сердца, а также почек, желудочно-кишечного тракта и глаз. Рассмотрены международные согласительные рекомендации по диагностике при подозрении на наличие ATTR-амилоидоза с использованием современных методов, облегчающие раннюю и точную диагностику. Рассматриваются причины и самые частые ошибочные диагнозы ATTR-амилоидоза, также приводящие к задержке своевременного назначения терапии. Молекулярно-генетическое тестирование следует рассматривать на ранней стадии обследования пациента с необъяснимой периферической нейропатией и кардиомиопатией. Диагностический алгоритм, основанный на начальных симптомах и проявлениях со стороны сердечно-сосудистой и нервной систем, облегчает идентификацию пациента с клиническим подозрением на ATTR-амилоидоз врачом общей практики. Ранняя диагностика критически важна для пациентов с ATTR-полинейропатией, так как раннее назначение препарата Виндакель (тафамидис), зарегистрированного в РФ в 2017 г., позволяет получить значимый клинический эффект. Своевременное назначение препарата Виндакель достоверно замедляет прогрессирование болезни, улучшает прогноз и качество жизни пациентов с ATTR-полинейропатией

C*-simplicity and the unique trace property for discrete groups

In this paper, we introduce new methods for working with group and crossed product C*-algebras that allow us to settle the longstanding open problem of characterizing groups with the unique trace property

Генетическая характеристика больных муковисцидозом в Российской Федерации по данным Национального регистра (2014)

The aim of this study was to investigate genetic features of patients with cystic fibrosis (CF) according to the National Register findings in Russia. Methods. The study involved 2,131 CF patients living in 74 regions of Russia who were included in the National Register of CF patients in 2014. Results. Genetic testing was performed in 89% of patients. The total mutant allele frequency was 81.2%. One hundred and twenty two mutations were found which comprised 173 genotypes; «mild» mutations took 23%. The most common mutant allele frequencies in the descending order were as follows: F508del, 51.53%; СFTRdele2,3, 5.93%; E92K, 2.62%; 3849+10kbC>T, 2.14%; 2184insA, 1.80%; W1282X, 1.80%; 2143delT, 1.69 %; N1303K, 1.43%; G542X, 1.16%; 1677delTA, 0.98%; L138ins, 0.95%; R334W, 0.85%; 394delTT, 0.85%; 3821delT, 0.42%; 2789+5G>A, 0.37%; S466X, 0.37%; S1196X, 0.37%; 3272-16T>A, 0.34%; W1282R, 0.29%; 3944delGT, 0.21%. Typical features of CFTR mutation distribution in Russian CF patients were lower frequency of mutations which are predominant worldwide, such as F508del, G542X, N1303K, and scarce G551D, 1717-1G>A, 2183AA>G mutations. On contrary, СFTRdele2,3, E92K, 2184insA, 2143delT, 1677delTA, L138ins mutations which are quite rare in Western Europe were encountered more often in Russia. «Mild» mutations were more common in Russian population of CF patients compared to European countries and have being increasing last years. Conclusion. Genetic features of Russian CF patients could be provided by Slavic, Turkic and Finno-Ugric genetic influence on Russian population.Генетическому разнообразию больных муковисцидозом (МВ) в России посвящены единичные работы на ограниченной выборке больных. Цель. Выявление особенностей генетического профиля больных МВ в России по данным Национального регистра (2014). Материалы и методы. Данные пациентов с МВ (n = 2 131) из 74 регионов России, включенные в Национальный регистр больных МВ (2014). Результаты. Генетическое обследование проведено у 89,0 % больных, суммарная аллельная частота выявленных мутаций составила 81,2 %. Выявлено 122 мутации, которые сформировали 173 различных генотипа, среди которых доля «мягких» генотипов составила 23,0 %. Аллельная частота самых распространенных мутаций представлена в порядке убывания: F508del – 51,53 %, СFTRdele2,3 – 5,93 %, E92K – 2,62 %, 3849+10kbC>T – 2,14 %, 2184insA – 1,80 %, W1282X – 1,80 %, 2143delT – 1,69 %, N1303K – 1,43 %, G542X – 1,16 %, 1677delTA – 0,98 %, L138ins – 0,95 %, R334W – 0,85 %, 394delTT – 0,85 %, 3821delT – 0,42 %, 2789+5G>A – 0,37 %, S466X – 0,37 %, S1196X – 0,37 %, 3272-16T>A – 0,34 %, W1282R – 0,29 %, 3944delGT – 0,21 %. Выявлено, что особенностями распределения мутаций. CFTRсреди российских больных МВ являются меньшая частота доминирующих в мире мутаций, таких как F508del, G542X, N1303K, единичная встречаемость мутаций G551D, 1717-1G>A, 2183AA>G и наоборот – более высокая частота мутаций, являющихся относительно редкими в западноевропейских странах: СFTRdele2,3, E92K, 2184insA, 2143delT, 1677delTA, L138ins. Другой особенностью является более высокая встречаемость «мягких» мутаций в России по сравнению со странами Европы. Выявлено, что доля «мягких» мутаций в популяции больных МВ на протяжении последних лет увеличивается. Заключение. При формировании населения России особенности генетического профиля российских больных МВ определяются славянскими, тюркскими и финно-угорскими влияниями