Анализ результатов использования потокоперенаправляющих стентов Pipeline в хирургическом лечении неразорвавшихся больших и гигантских параклиноидных аневризм внутренней сонной артерии

Background: Both the high frequency of recurrence of large or giant paraclinoid aneurysms (PA) of the internal carotid artery and the occurrence of intra- and postoperative complications, leading to unsatisfactory results of surgical treatment of this group of patients, make the stated problem urgent. Flow-diverter embolization devices are actively used in many large international neurosurgical centers for the treatment of cerebral aneurysms of different morphology, size, and localization. Currently, there are very few reports on the effectiveness of the use of flow diverting stents in the surgical treatment of large and giant PA of the internal carotid artery. The results of these studies are controversial and largely contradictory. Aim: Outcome analysis of the use of Pipeline embolization device (PED) for the surgical treatment of large and giant carotid PA. Methods: The study enrolled 37 patients (25 women, 12 men; mean age 51.7±10.7 years) who were divided into those treated with the PED alone versus those treated with the PED and concurrent coil embolization. The average follow-up period was 19.7±3.8 months. Results: In 56.7% of cases, PA caused the development of an insignificant neurological deficit (Modified Rankin Scale 1−2). In 18.9% of patients, PA provoked a gross neurologic deficit (MRS 3−5). 24.3% of patients with PA did not have any clinical-neurological manifestations. After the surgery, neurologic status improved in 32.4% of patients, remained the same — in 45.9% of cases, and the degree of neurologic deficit increased in 21.6%. PED procedure was performed in 70.2% of patients. In 29.7% of cases, the dislocation of large or giant PA of the internal carotid artery from the systemic blood stream was performed using PED and concurrent coil embolization. At the indicated period of patient observation, complete occlusion of large and giant carotid PA was achieved in 75.6% of cases, almost complete and partial occlusion — in 24.3%. The incidence of thromboembolic and hemorrhagic complications was 10.8% and 8.1%, respectively. Mortality rate among patients was 2.7%. Conclusions: The use of PED is an effective method for occluding large or giant PA of the internal carotid artery. Nevertheless, this method of endovascular treatment of PA is associated with a high complication incidence.Обоснование. Высокая частота рецидивов больших и гигантских параклиноидных аневризм (ПА) внутренней сонной артерии, а также наличие интра- ипослеоперационных нежелательных явлений, приводящих к неудовлетворительным результатам хирургического лечения данной группы пациентов, обусловливают актуальность указанной проблемы. Потокоперенаправляющие стенты (ППНС) активно используются во многих крупных нейрохирургических центрах мира при лечении аневризм сосудов головного мозга различной морфологии, размеров и локализации. Кнастоящему времени существуют лишь единичные сообщения, посвященные оценке эффективности использования ППНС в хирургическом лечении больших и гигантских ПА внутренней сонной артерии, а результаты указанных исследований неоднозначны иво многом противоречивы. Цель исследования ― анализ результатов использования ППНС Pipeline в хирургическом лечении больших и гигантских ПА внутренней сонной артерии. Методы. В исследование включены 37 пациентов (25 женщин, 12 мужчин; средний возраст 51,7±10,7 года), которым выполнена установка ППНС изолированно или в комбинации с отделяемыми спиралями по поводу больших и гигантских ПА внутренней сонной артерии. Средний период наблюдения за пациентами составил 19,7±3,8 мес. Результаты. В 56,7% случаев ПА являлись причиной развития незначительного неврологического дефицита (1−2 балла по модифицированной шкале Рэнкина). У 18,9% пациентов ПА вызывали грубый неврологический дефицит (3−5 баллов по модифицированной шкале Рэнкина). Не имели клинико-неврологических проявлений 24,3% пациентов с ПА. После выполнения оперативного вмешательства у 32,4% пациентов отмечено улучшение неврологического статуса, в45,9% случаев неврологический статус остался на прежнем уровне и в 21,6% ― степень неврологического дефицита увеличилась. Установка только ППНС выполнена у 70,2% пациентов. В 29,7% случаев выключение больших и гигантских ПА внутренней сонной артерии из системного кровотока выполнено с использованием комбинации ППНС иотделяемых спиралей. В указанный период наблюдения за пациентами полной окклюзии больших и гигантских ПА внутренней сонной артерии удалось достигнуть в75,6% случаев, практически полной и частичной окклюзии ― в 24,3%. Частота встречаемости тромбоэмболических и геморрагических осложнений составила 10,8 и8,1% соответственно. Смертность среди пациентов составила 2,7%. Заключение. Использование ППНС Pipeline является эффективным способом окклюзии больших игигантских ПА внутренней сонной артерии. Тем не менее указанный способ эндоваскулярного лечения ПА ассоциирован с высокой частотой нежелательных явлений

Possibility of local pair existence in optimally doped SmFeAsO₁₋х in pseudogap regime

We report the analysis of pseudogap Δ* derived from resistivity experiments in FeAs-based superconductor SmFeAsO₀.₈₅, having a critical temperature Tc=55 K. Rather specific dependence Δ*(T) with two representative temperatures followed by a minimum at about 120 K was observed. Below Ts ≈ 147 K, corresponding to the structural transition in SmFeAsO, Δ*(T) decreases linearly down to the temperature TAFM ≈ 133 K. This last peculiarity can likely be attributed to the antiferromagnetic (AFM) ordering of Fe spins. It is believed that the found behavior can be explained in terms of Machida, Nokura, and Matsubara theory developed for the AFM superconductors

Current status of turbulent dynamo theory: From large-scale to small-scale dynamos

Several recent advances in turbulent dynamo theory are reviewed. High resolution simulations of small-scale and large-scale dynamo action in periodic domains are compared with each other and contrasted with similar results at low magnetic Prandtl numbers. It is argued that all the different cases show similarities at intermediate length scales. On the other hand, in the presence of helicity of the turbulence, power develops on large scales, which is not present in non-helical small-scale turbulent dynamos. At small length scales, differences occur in connection with the dissipation cutoff scales associated with the respective value of the magnetic Prandtl number. These differences are found to be independent of whether or not there is large-scale dynamo action. However, large-scale dynamos in homogeneous systems are shown to suffer from resistive slow-down even at intermediate length scales. The results from simulations are connected to mean field theory and its applications. Recent work on helicity fluxes to alleviate large-scale dynamo quenching, shear dynamos, nonlocal effects and magnetic structures from strong density stratification are highlighted. Several insights which arise from analytic considerations of small-scale dynamos are discussed.Comment: 36 pages, 11 figures, Spa. Sci. Rev., submitted to the special issue "Magnetism in the Universe" (ed. A. Balogh

Measurement of e+e- -> pi+pi- cross section with CMD-2 around rho-meson

The cross section of the process e+e- -> pi+pi- has been measured using about 114000 events collected by the CMD-2 detector at the VEPP-2M e+e- collider in the center-of-mass energy range from 0.61 to 0.96 GeV. Results of the pion form factor determination with a 0.6% systematic uncertainty are presented. Implications for the hadronic contribution to the muon anomalous magnetic moment are discussed.Comment: 17 pages, 4 figures, submitted to PL

Role of turbulence and electric fields in the establishment of improved confinement in tokamak plasmas

An extensive (INTAS) research programme started in 2002 to investigate the correlations between on the one hand the occurrence of transport barriers and improved confinement in the medium-size tokamaks TEXTOR and T-10 and on the smaller tokamaks FT-2, TUMAN-3M and CASTOR, and on the other hand electric fields, modified magnetic shear and electrostatic and magnetic turbulence using advanced diagnostics with high spatial and temporal resolution and of various active means to externally control plasma transport . This has been done in a strongly coordinated way and exploiting the complementarity of TEXTOR and T-10 and the backup potential of the three other tokamaks, which together have all the relevant experimental tools and theoretical expertise

Recovery of dialysis patients with COVID-19 : health outcomes 3 months after diagnosis in ERACODA

Background. Coronavirus disease 2019 (COVID-19)-related short-term mortality is high in dialysis patients, but longer-term outcomes are largely unknown. We therefore assessed patient recovery in a large cohort of dialysis patients 3 months after their COVID-19 diagnosis. Methods. We analyzed data on dialysis patients diagnosed with COVID-19 from 1 February 2020 to 31 March 2021 from the European Renal Association COVID-19 Database (ERACODA). The outcomes studied were patient survival, residence and functional and mental health status (estimated by their treating physician) 3 months after COVID-19 diagnosis. Complete follow-up data were available for 854 surviving patients. Patient characteristics associated with recovery were analyzed using logistic regression. Results. In 2449 hemodialysis patients (mean ± SD age 67.5 ± 14.4 years, 62% male), survival probabilities at 3 months after COVID-19 diagnosis were 90% for nonhospitalized patients (n = 1087), 73% for patients admitted to the hospital but not to an intensive care unit (ICU) (n = 1165) and 40% for those admitted to an ICU (n = 197). Patient survival hardly decreased between 28 days and 3 months after COVID-19 diagnosis. At 3 months, 87% functioned at their pre-existent functional and 94% at their pre-existent mental level. Only few of the surviving patients were still admitted to the hospital (0.8-6.3%) or a nursing home (∼5%). A higher age and frailty score at presentation and ICU admission were associated with worse functional outcome. Conclusions. Mortality between 28 days and 3 months after COVID-19 diagnosis was low and the majority of patients who survived COVID-19 recovered to their pre-existent functional and mental health level at 3 months after diagnosis