A new life for sterile neutrino dark matter after the pandemic

We propose a novel mechanism to generate sterile neutrinos $\nu_s$ in theearly Universe, by converting ordinary neutrinos $\nu_\alpha$ in scatteringprocesses $\nu_s\nu_\alpha\to\nu_s\nu_s$. After initial production byoscillations, this leads to an exponential growth in the $\nu_s$ abundance. Weshow that such a production regime naturally occurs for self-interacting$\nu_s$, and that this opens up significant new parameter space where $\nu_s$make up all of the observed dark matter. Our results provide strong motivationto further push the sensitivity of X-ray line searches, and to improve onconstraints from structure formation.<br

A new life for sterile neutrino dark matter after the pandemic

We propose a novel mechanism to generate sterile neutrinos $\nu_s$ in the early Universe, by converting ordinary neutrinos $\nu_\alpha$ in scattering processes $\nu_s\nu_\alpha\to\nu_s\nu_s$. After initial production by oscillations, this leads to an exponential growth in the $\nu_s$ abundance. We show that such a production regime naturally occurs for self-interacting $\nu_s$, and that this opens up significant new parameter space where $\nu_s$ make up all of the observed dark matter. Our results provide strong motivation to further push the sensitivity of X-ray line searches, and to improve on constraints from structure formation

A new life for sterile neutrino dark matter after the pandemic

We propose a novel mechanism to generate sterile neutrinos $\nu_s$ in theearly Universe, by converting ordinary neutrinos $\nu_\alpha$ in scatteringprocesses $\nu_s\nu_\alpha\to\nu_s\nu_s$. After initial production byoscillations, this leads to an exponential growth in the $\nu_s$ abundance. Weshow that such a production regime naturally occurs for self-interacting$\nu_s$, and that this opens up significant new parameter space where $\nu_s$make up all of the observed dark matter. Our results provide strong motivationto further push the sensitivity of X-ray line searches, and to improve onconstraints from structure formation.<br

Design and synthesis of Nrf2-derived hydrocarbon stapled peptides for the disruption of protein-DNA-interactions

Misregulation and mutations of the transcription factor Nrf2 are involved in the development of a variety of human diseases. In this study, we employed the technology of stapled peptides to address a protein-DNA-complex and designed a set of Nrf2-based derivatives. Varying the length and position of the hydrocarbon staple, we chose the best peptide for further evaluation in both fixed and living cells. Peptide 4 revealed significant enrichment within the nucleus compared to its linear counterpart 5, indicating potent binding to DNA. Our studies suggest that these molecules offer an interesting strategy to target activated Nrf2 in cancer cells

Association of lower fractional flow reserve values with higher risk of adverse cardiac events for lesions deferred revascularization among patients with acute coronary syndrome

BACKGROUND: The safety of deferring revascularization based on fractional flow reserve (FFR) during acute coronary syndrome (ACS) is unclear. We evaluated the association of FFR and adverse cardiac events among patients with coronary lesions deferred revascularization based on FFR in the setting of ACS versus non-ACS. METHODS AND RESULTS: The study population (674 patients; 816 lesions) was divided into ACS (n=334) and non-ACS (n=340) groups based on the diagnosis when revascularization was deferred based on FFR values >0.80 between October 2002 and July 2010. The association and interaction between FFR and clinical outcomes was evaluated using Cox proportional hazards models within each group (mean follow-up of 4.5±2.1 years). Subsequent revascularization of a deferred lesion was classified as a deferred lesion intervention (DLI), whereas the composite of DLI or myocardial infarction (MI) attributed to a deferred lesion was designated as deferred lesion failure (DLF). In the non-ACS group, lower FFR values were not associated with any increase in adverse cardiac events. In the ACS group, every 0.01 decrease in FFR was associated with a significantly higher rate of cardiovascular death, MI, or DLI (hazard ratio [HR], 1.08; 95% confidence interval [CI], 1.03 to 1.12), MI or DLI (HR, 1.09; 95% CI: 1.04 to 1.14), DLF (HR, 1.12; 95% CI, 1.06 to 1.18), MI (HR, 1.07; 95% CI, 1.00 to 1.14), and DLI (HR, 1.12; 95% CI, 1.06 to 1.18). CONCLUSION: Lower FFR values among ACS patients with coronary lesions deferred revascularization based on FFR are associated with a significantly higher rate of adverse cardiac events. This association was not observed in non-ACS patients

Объемная капнография как способ оценки эффективности альвеолярной вентиляции в клинической практике

The purpose of the study was to compare the relationship between the dead space volume and tidal volume (VD/VT) using volumetric capnography (VCap) during pressure controlled (PCV) and pressure supported (PSV) ventilation mode in the postoperative period.Materials and methods. 30 randomly assigned cardiac surgical patients undergoing CABG (coronary artery bypass grafting) using ECC (extracorporeal circuit) were included in an observational, prospective study. Patients were connected to the ventilator immediately after ICU admission. After that, monitoring VD/VT, CO2 production (VECO2) as well as ventilation parameters was carried out. The parameters during PCV and PSV mode were statistically evaluated using t-test.Results. Expiratory CO2 (ETCO2) concentration were not significantly different in both PCV or PSV (p=NS), although both VECO2 and minute ventilation (MV) increased during PSV mode (p&lt;0.01). VD/VT in PSV mode was lower than in PCV. Gas exchange represented by alveolar ventilation (VA) was better during PSV (p&lt;0.01). VA was also higher during PSV (p&lt;0.05). The calculated VD/VT ratio differed between PCV and PSV mode (p&lt;0.01).Conclusion. VCap represents a tool for monitoring of CO2 exchange effectivness. We registered a decrease in VD/VT with improved alveolar ventilation (VA) in PSV mode. VCap seems to be a suitable instrument for adjustment of protective lung ventilation.Цель исследования — сравнить взаимосвязь между объемом мертвого пространства и дыхательным объемом (VD/VT) методом объемной капнографии (VCap) в режимах искусственной вентиляции легких с управляемым давлением (PCV) и поддержкой давлением (PSV) в послеоперационном периоде.Материалы и методы. В обсервационное, проспективное исследование методом случайного выбора включили 30 пациентов из отделения сердечно-сосудистой хирургии, перенесших операцию аортокоронарного шунтирования (АКШ) с экстракорпоральным кровообращением. Пациентов подключали к системе вентиляции легких сразу при поступлении в отделение интенсивной терапии. Затем проводили мониторинг VD/VT, продукции CO2 (VECO2), а также параметров вентиляции. Параметры вентиляции в режимах с управляемым давлением (PCV) и поддержкой давлением (PSV) статистически оценивалиРезультаты. Не выявили достоверных различий концентрации CO2 во выдыхаемом воздухе (ETCO2) между режимами PCV и PSV (p=NS), хотя как VECO2, так и минутная вентиляция (MV) возрастали в режиме PSV (p&lt;0,01). Отношение VD/VT в режиме PSV было ниже, чем в режиме PCV. Газообмен, представленный альвеолярной вентиляцией (VA), был лучше в режиме PSV (p&lt;0,01). Показатель VA был также выше в режиме PSV (p&lt;0,05). Расчетное отношение VD/VT различалось между режимами PCV и PSV (p&lt;0,01).Заключение. Объемная капнография (VCap) является средством мониторинга эффективности обмена CO2. Отмечали снижение VD/VT с улучшением альвеолярной вентиляции (VA) в режиме PSV. VCap представляется подходящим методом регулирования протективной вентиляции легких

Emerging Utilization of Transcatheter Tricuspid Valve Replacement in Severe Tricuspid Regurgitation

Emerging Utilization of Transcatheter Tricuspid Valve Replacement in Severe Tricuspid Regurgitation, Dr. Anas Hashem, RGH IMRP and Dr. Jeremiah Depta, Cardiology Department Objectives: Anatomy and physiology of Tricuspid Valve (TV) Pathophysiology across TV and associated symptoms Current diagnostic modalities and criteria Levels of TV regurgitation and its hemodynamic changes Conservative management strategies vs Indications for procedural interventions Emerging technologies and future direction