Clinical Implication of Cardiac Valve Allografts in Rare Surgical Circumstances

The unique clinical and surgical experience with cardiac valve allografts is presented in the study. Cutting-edge approach with regard to clinical course of the disease, particular diagnostic findings, patient’s preference, and allograft accessibility is highlighted in case series. State-of-the-art techniques, initial and mid-term results are summarized with a specific focus on allograft tissue application in cardiovascular surgery. Four patients underwent surgery during the period between February 2020 and February 2023 with inferior vena cava tumor involvement, destructive double valve endocarditis, rheumatic aortic and mitral insufficiency, and severe tricuspid regurgitation in patients with large ostium secundum and atrial fibrillation. All patients demonstrated an uneventful postoperative course

Femtomolar detection of the heart failure biomarker NT-proBNP in artificial saliva using an immersible liquid-gated aptasensor with reduced graphene oxide

Measuring NT-proBNP biomarker is recommended for preliminary diagnostics of the heart failure. Recent studies suggest a possibility of early screening of biomarkers in saliva for non-invasive identification of cardiac diseases at the point-of-care. However, NT-proBNP concentrations in saliva can be thousand time lower than in blood plasma, going down to pg/mL level. To reach this level, we developed a label-free aptasensor based on a liquid-gated field effect transistor using a film of reduced graphene oxide monolayer (rGO-FET) with immobilized NT-proBNP specific aptamer. We found that, depending on ionic strength of tested solutions, there were different levels of correlation in responses of electrical parameters of the rGO-FET aptasensor, namely, the Dirac point shift and transconductance change. The correlation in response to NT-proBNP was high for 1.6 mM phosphate-buffered saline (PBS) and zero for 16 mM PBS in a wide range of analyte concentrations, varied from 1 fg/mL to 10 ng/mL. The effects of transconductance and Dirac point shift in PBS solutions of different concentrations are discussed. The biosensor exhibited a high sensitivity for both transconductance (2 uS/decade) and Dirac point shift (2.3 mV/decade) in diluted PBS with the linear range from 10 fg/mL to 1 pg/mL. The aptasensor performance has been also demonstrated in undiluted artificial saliva with the achieved limit of detection down to 41 fg/mL (~4.6 fM)

Niemann–Pick type C disease as proof-of-concept for intelligent biomarker panel selection in neurometabolic disorders

AIM: Using Niemann-Pick type C disease (NPC) as a paradigm, we aimed to improve biomarker discovery in patients with neurometabolic disorders. METHOD: Using a multiplexed liquid chromatography tandem mass spectrometry dried bloodspot assay, we developed a selective intelligent biomarker panel to monitor known biomarkers N-palmitoyl-O-phosphocholineserine and 3β,5α,6β-trihydroxy-cholanoyl-glycine as well as compounds predicted to be affected in NPC pathology. We applied this panel to a clinically relevant paediatric patient cohort (n = 75; 35 males, 40 females; mean age 7 years 6 months, range 4 days-19 years 8 months) presenting with neurodevelopmental and/or neurodegenerative pathology, similar to that observed in NPC. RESULTS: The panel had a far superior performance compared with individual biomarkers. Namely, NPC-related established biomarkers used individually had 91% to 97% specificity but the combined panel had 100% specificity. Moreover, multivariate analysis revealed long-chain isoforms of glucosylceramide were elevated and very specific for patients with NPC. INTERPRETATION: Despite advancements in next-generation sequencing and precision medicine, neurological non-enzymatic disorders remain difficult to diagnose and lack robust biomarkers or routine functional testing for genetic variants of unknown significance. Biomarker panels may have better diagnostic accuracy than individual biomarkers in neurometabolic disorders, hence they can facilitate more prompt disease identification and implementation of emerging targeted, disease-specific therapies

Формирование фотоприемных структур ИК-диапазона путем пересыщения кремния теллуром

The Si layers doped with Te up to the concentrations of (3–5)1020 cm–3 have been formed via ion implantation and pulsed laser melting. It is found, 70–90 % of the embedded impurity atoms are in substitution states in the silicon lattice. These layers have revealed significant absorption (35–66 %) in the wavelength λ range of 1100–2500 nm. In this case, the absorption coefficient increases with the λ growth. The absorption spectra of the implanted layers after pulsed laser melting, equilibrium furnace annealing, and rapid thermal annealing have been compared. It is shown that equilibrium furnace annealing increases the photon absorption by 4 % in the wavelength range of 1100–2500 nm in comparison with virgin Si. After rapid thermal annealing, the photon absorption in the IR-range increases only by 2 %.Слои кремния, легированные теллуром до концентраций (3–5)1020 см–3, получены ионной имплантацией с последующим импульсным лазерным отжигом. Показано, что 70–90 % внедренной примеси находится в позиции замещения в решетке кремния. Слои, гиперпересыщенные теллуром, проявляют существенное поглощение (35–66 %) в области длин волн 1100–2500 нм, причем коэффициент поглощения увеличивается с ростом длины волны. Проведено сравнение спектров поглощения имплантированных слоев после лазерного отжига, а также после равновесного и быстрого термического отжигов. Показано, что равновесный отжиг после имплантации ионов теллура увеличивает поглощение фотонов в области длин волн 1100–2500 нм на 4 % по сравнению с неимплантированным кремнием. После быстрого термического отжига поглощение в ИК-области возрастает лишь на 2 %

ПРОТЕЗИРОВАНИЕ АОРТАЛЬНОГО КЛАПАНА АУТОПЕРИКАРДОМ БЕЗ ИСПОЛЬЗОВАНИЯ ШАБЛОНОВ: НЕПОСРЕДСТВЕННЫЕ И СРЕДНЕОТДАЛЕННЫЕ РЕЗУЛЬТАТЫ

HighlightsWe have described the outcomes of aortic valve replacement using autologous pericardium without special templates. Although S. Ozaki is considered by many to be the founder of neocuspidization technique, the methods for sizing of the neocusps were proposed long before him. The method of the Japanese professor involves using special templates. This article presents a mathematical formula to calculate neocusps` size, which significantly simplifies the procedure, and makes it possible to perform it in centers that do not possess Ozaki templates. Abstract Aim: To describe an original technique of aortic valve replacement using autologous pericardium without templates. The calculation of the neocusps` size is based on the diameter of aortic annulus, which can be estimated both intraoperatively and preoperatively, helps to reduce the duration of surgery, CPB time and myocardial ischemia, and lower the rates of late complications.Methods: The prospective study included 34 patients with aortic valve disease admitted to the Cardiac Surgical Department of the University Clinical Hospital No.1 of the First Moscow State Medical University named after I.M. Sechenov, Ministry of Health of Russia in the period from January 2020 to March 2023. The mean age of the patients was 51±17 years (from 19 to 78 years). Gender distribution in the total group was as follows: male 50% (n = 17), female 50% (n = 17). All patients underwent aortic valve replacement using autologous pericardium without templates (by calculating the neocusps` size). Isolated aortic valve replacement was performed in 17 patients (50%), ascending aorta replacement in 11 patients (32.3%), mitral valve intervention in 5 (14.7%), coronary artery bypass grafting in 3 (8.8%) cases. 11 patients (32.3%) had aortic valve stenosis, 4 patients (11.7%) had insufficiency, and 19 patients (55.8%) had both stenosis and insufficiency. Bicuspid aortic valve was detected in 18 patients (52.9%). All patients were divided into two groups: Komarov (aortic valve replacement only) and Komarov Plus (aortic valve replacement and treatment for concomitant cardiac pathology).Results: There were no cases of conversion to traditional aortic valve replacement using prosthetic valves. There were 2 cases of in-hospital mortality; according to medical records, death in both cases was due to complications provoked by double pneumonia caused by SARS-CoV-2. 1 patient required reoperation 4 months after the intervention due endocarditis caused by Streptococcus viridans. In the midterm follow-up period, hemodynamic parameters such as peak gradient, mean gradient, and peak velocity were 11.96±4.70 mm Hg, 5.88±2.07 mm Hg, 168.19±30.56 mm Hg.Conclusions: The obtained valve prosthesis is anatomically analogous to the native valve and provides reliable peak pressure reduction, no postoperative regurgitation, and increased effective orifice area. The proposed method is safe and can serve as an alternative to the Ozaki procedure, in which the neocusps are outlined using special templates.Основные положения Продемонстрированы результаты протезирования аортального клапана аутоперикардом без использования шаблонов. Родоначальником неокуспидизации принято считать S. Ozaki, однако методы расчета неостворки из перикарда предложены задолго до него. Методика японского профессора заключается в использовании специальных шаблонов. В данной статье представлен математический расчет створки, выполненный хирургами Сеченовского Университета, позволяющий не только существенно упростить процедуру, но и выполнять ее в тех центрах, где шаблонов Ozaki нет. Резюме Цель: Описана оригинальная методика полной реконструкции аортального клапана аутоперикардом. Расчет формы неостворок осуществлен на основании данных о диаметре фиброзного кольца, которые могут быть получены как во время, так и до операции, что позволяет сократить время вмешательства, искусственного кровообращения и ишемии миокарда, а в конечном итоге добиться снижения ишемии головного мозга и снизить вероятность поздних осложнений.Материалы и методы: Проведено проспективное исследование 34 пациентов, оперированных по поводу порока аортального клапана в кардиохирургическом отделении Университетской клинической больницы № 1 ФГАОУ ВО Первый МГМУ им. И.М. Сеченова Минздрава России (Сеченовский Университет) в период с января 2020 г. по март 2023 г. Средний период наблюдения для всей когорты составил 14,1±7,7 мес. Средний возраст больных – 51±17 лет (19–78 лет). Гендерное распределение в общей группе: мужской пол – 50% (n = 17), женский – 50% (n = 17). Всем пациентам выполнено протезирование аортального клапана аутоперикардом без использования шаблонов (расчетным способом). 17 (50%) больным проведена изолированная коррекция порока аортального клапана, 11 (32,3%) – протезирование восходящей аорты, 5 (14,7%) – вмешательство на митральном клапане, в 3 (8,8%) случаях выполнено коронарное шунтирование. Стеноз аортального клапана отмечен у 11 (32,3%) пациентов, недостаточность – у 4 (11,7%), стеноз и недостаточность – у 19 (55,8%). Двустворчатый аортальный клапан выявлен у 18 (52,9%) больных. Все пациенты разделены на две группы: Komarov (изолированная коррекция порока аортального клапана) и Komarov Plus (коррекция порока аортального клапана с сопутствующей кардиальной патологией).Результаты: Не зарегистрировано случаев конверсии в стандартное протезирование аортального клапана. Зафиксировано два случая госпитальной летальности; по данным патологоанатомического заключения, смерть в обоих случаях наступила из-за осложнений, спровоцированных двусторонней полисегментарной пневмонией, вызванной SARS-CoV-2. Одному пациенту через 4 мес. после вмешательства потребовалась повторная операция вследствие развившегося эндокардита, возбудитель Streptococcus viridans. В среднеотдаленном периоде гемодинамические показатели, такие как пиковый градиент, средний градиент и пиковая скорость, составили 11,96±4,70, 5,88±2,07 мм рт. ст. и 168,19±30,56 см/с.Заключение: Конечный вид протеза служит анатомическим аналогом нативного клапана и обеспечивает достоверное снижение пикового давления, отсутствие регургитации на клапане после операции и увеличение площади эффективного отверстия. Данный метод можно рассматривать как безопасную альтернативу процедуре Ozaki, при которой створки выкраивают с помощью специальных шаблонов

How Internet of Things Influences Human Behavior Building Social Web of Services via Agent-Based Approach

The paper discovers potential human interactions with growing amount of internet of things (IoT) via proposed concept of Social Web of Services (classical social web with smart things - daily life objects connected to the internet). To investigate the impact of IoT on user behaviour patterns we modelled human-thing interactions using agent-based simulation (ABM). We have proved that under certain conditions SmartThings, connected to the IoT, are able to change patterns of Human behaviour. Results of this work predict our way of living in the era of caused by viral effects of IoT application (HCI and M2M connections), and could be used to foster business process management in the IoT era

Trimethylammonium Sn(IV) and Pb(IV) Chlorometalate Complexes with Incorporated Dichlorine

Supramolecular dichloro-chlorostannate(IV) and -plumbate(IV) complexes (Me3NH)2{[MCl6]Cl2} (M = Sn (1), Pb (2)) feature dichlorine units incorporated into a halometalate framework. Both compounds were characterized by X-ray diffractometry and Raman spectroscopy

Photoluminescence Properties of InAs Quantum Dots Overgrown by a Low-Temperature GaAs Layer under Different Arsenic Pressures

We studied the influence of the arsenic pressure during low-temperature GaAs overgrowth of InAs quantum dots on their optical properties. In the photoluminescence spectrum of quantum dots overgrown at a high arsenic pressure, we observed a single broad line corresponding to unimodal size distribution of quantum dots. Meanwhile, two distinct peaks (~1080 and ~1150 nm) at larger wavelengths are found in the spectra of samples with quantum dots overgrown at a low arsenic pressure. We attributed this phenomenon to the high-pressure suppression of atom diffusion between InAs islands at the overgrowth stage, which makes it possible to preserve the initial unimodal size distribution of quantum dots. The same overgrowth of quantum dots at the low arsenic pressure induces intensive mass transfer, which leads to the formation of arrays of quantum dots with larger sizes. Integrated photoluminescence intensity at 300 K is found to be lower for quantum dots overgrown at the higher arsenic pressure. However, a difference in the photoluminescence intensity for the high- and low-pressure overgrowths is not so significant for a temperature of 77 K. This indicates that excess arsenic incorporates into the capping layer at high arsenic pressures and creates numerous nonradiative recombination centers, diminishing the photoluminescence intensity

Influence of the Arsenic Pressure during Rapid Overgrowth of InAs/GaAs Quantum Dots on Their Photoluminescence Properties

In this paper, for the first time, we report a strong effect of the arsenic pressure used for the high-rate GaAs capping of self-assembled InAs quantum dots on their optical properties. A 140 nm red shift of the photoluminescence peak position is observed when the overgrowth arsenic pressure increases threefold. We explain this behavior in terms of different intensities of quantum dot decomposition, which occurs during the overgrowth under different conditions. When the arsenic pressure is sufficiently high, a GaAs capping layer is formed by deposited species with a low impact on initial quantum dots. At a low arsenic pressure, arsenic deficiency leads to the intensive intermixing caused both by the enhanced Ga/In atom exchange and by the consumption of arsenic atoms belonging to quantum dots for the GaAs capping layer formation. As a result of the overgrowth, quantum dots are divided into families with a large (high pressure) and a small (low pressure) average size, yielding long-wave (1.23 µm) and short-wave (1.09 µm) photoluminescence peaks, respectively. Thus, a significant influence of the overgrowth arsenic pressure on the characteristics of InAs quantum dots is evidenced in this study

Automated Detection, Exploitation, and Elimination of Double-Fetch Bugs using Modern CPU Features

International audienceDouble-fetch bugs are a special type of race condition, where an unprivileged execution thread is able to change a memory location between the time-of-check and time-of-use of a privileged execution thread. If an unprivileged attacker changes the value at the right time, the privileged operation becomes inconsistent, leading to a change in control flow, and thus an escalation of privileges for the attacker. More severely, such double-fetch bugs can be introduced by the compiler, entirely invisible on the source-code level. We propose novel techniques to efficiently detect, exploit, and eliminate double-fetch bugs. We demonstrate the first combination of state-of-the-art cache attacks with kernel-fuzzing techniques to allow fully automated identification of double fetches. We demonstrate the first fully automated reliable detection and exploitation of double-fetch bugs, making manual analysis as in previous work superfluous. We show that cache-based triggers outperform state-of-the-art exploitation techniques significantly, leading to an exploitation success rate of up to 97 %. Our modified fuzzer automatically detects double fetches and automatically narrows down this candidate set for double-fetch bugs to the exploitable ones. We present the first generic technique based on hardware transactional memory, to eliminate double-fetch bugs in a fully automated and transparent manner. We extend defensive programming techniques by retrofitting arbitrary code with automated double-fetch prevention , both in trusted execution environments as well as in syscalls, with a performance overhead below 1 %