Publications by authors named "Sobotka P"

Activation of the sympathetic nervous system has been attributed to the development of hypertension. Two established approaches for treating hypertension are pharmacotherapy and lifestyle changes. With an improved understanding of renal nerve anatomy and physiology, renal denervation has been proposed as an alternative treatment for hypertension.

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Detecting extremely low light signals is the basis of many scientific experiments and measurement techniques. For many years, a high-voltage photomultiplier has been the only practical device used in the visible and infrared spectral range. However, such a solution is subject to several inconveniences, including high production costs, the requirements of a supply voltage of several hundred volts, and a high susceptibility to mechanical damage.

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Background: Previous trials of renal denervation (RDN) have been designed to investigate reduction of blood pressure (BP) as the primary efficacy endpoint using non-selective RDN without intraoperatively verified RDN success. It is an unmet clinical need to map renal nerves, selectively denervate renal sympathetic nerves, provide readouts for the interventionalists and avoid futile RDN. We aimed to examine the safety and efficacy of renal nerve mapping/selective renal denervation (msRDN) in patients with uncontrolled hypertension (HTN) and determine whether antihypertensive drug burden is reduced while office systolic BP (OSBP) is controlled to target level (<140 mmHg).

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Recent advances in wearable technology through convenient and cuffless systems will enable continuous, noninvasive monitoring of blood pressure (BP), heart rate, and heart rhythm on both longitudinal 24-hour measurement scales and high-frequency beat-to-beat BP variability and synchronous heart rate variability and changes in underlying heart rhythm. Clinically, BP variability is classified into 4 main types on the basis of the duration of monitoring time: very-short-term (beat to beat), short-term (within 24 hours), medium-term (within days), and long-term (over months and years). BP variability is a strong risk factor for cardiovascular diseases, chronic kidney disease, cognitive decline, and mental illness.

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Renal denervation (RDN) is proposed as a durable and patient compliance independent treatment for hypertension. However, 20-30% non-responder after RDN treatment weakened the therapeutic effect, which may be due to blind ablation. The renal nerve mapping/selective ablation system developed by SyMap Medical Ltd (Suzhou), China, has the function of mapping renal sympathetic/parasympathetic nerve sites and selectively removing renal sympathetic nerves and is expected to meet the urgent unmet clinical need of targeted RDN.

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Pelvic venous disorders are inter-related pathologic conditions caused by reflux and obstruction in the pelvic veins. It can present a spectrum of clinical features based on the route of transmission of venous hypertension to either distal or caudal venous reservoirs. Imaging can help to visualize pelvic vascular and visceral structures to rule out other gynecologic, gastrointestinal, and urologic diseases.

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Device therapy for severe heart failure (HF) has shown efficacy both in acute and chronic settings. Recent percutaneous device innovations have pioneered a field known as interventional HF, providing clinicians with a variety of options for acute decompensated HF that are centered on nonsurgical mechanical circulatory support. Other structural-based therapies are aimed at the pathophysiology of chronic HF and target the underlying etiologies such as functional mitral regurgitation, ischemic cardiomyopathy, and increased neurohumoral activity.

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This work presents research on unique optofluidic systems in the form of air channels fabricated in PDMS and infiltrated with liquid crystalline material. The proposed LC:PDMS structures represent an innovative solution due to the use of microchannel electrodes filled with a liquid metal alloy. The latter allows for the easy and dynamic reconfiguration of the system and eliminates technological issues experienced by other research groups.

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Compliant mechanisms have gained an increasing interest in recent years, especially in relation to the possibility of using 3D printers for their production. These mechanisms typically find applications in precise positioning systems of building robotic devices or in sensing where they can be used to characterize displacement. Three-dimensional printing with PLA materials allows fiber optic-based sensors to be incorporated into the structures of properly designed compliant mechanisms.

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Unlabelled: There are several accepted methods to verify External Beam Radiation Therapy (EBRT) treatment plans, but there is no standard way to check the quality of a brachytherapy treatment plan.

Purpose: This feasibility study assesses whether the ArcCHECK EBRT radiation detector can also be used to verify Treatment Planning System software quality check procedures for brachytherapy.

Methods And Materials: ArcCHECK is a three-dimensional matrix of 1386 semiconductor diodes, arranged spirally around an internal cylindrical space that is 32 cm long and 15 cm in diameter.

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The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has completely disrupted people’s lives. All over the world, many restrictions and precautions have been introduced to reduce the spread of coronavirus disease 2019 (COVID-19). Ultraviolet C (UV-C) radiation is widely used to disinfect rooms, surfaces, and medical tools; however, this paper presents novel results obtained for modern UV-C light-emitting diodes (LEDs), examining their effect on inhibiting the multiplication of viruses.

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Volume recruitment from the splanchnic compartment is an important physiological response to stressors such as physical activity and blood loss. In the setting of heart failure (HF), excess fluid redistribution from this compartment leads to increased cardiac filling pressures with limitation in exercise capacity. Recent evidence suggests that blocking neural activity of the greater splanchnic nerve (GSN) could have significant benefits in some patients with HF by reducing cardiac filling pressures and improving exercise capacity.

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While many of the cardiac limitations to exercise performance are now well-characterized, extracardiac limitations to exercise performance have been less well recognized but are nevertheless important. We propose that abnormalities of cardiac preload reserve represents an under-recognized but common cause of exercise limitations. We further propose that mechanistic links exist between conditions as seemingly disparate as heart failure with preserved ejection fraction, nonalcoholic fatty liver disease, and pelvic venous compression/obstruction syndromes (eg, May-Thurner).

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Polymer-matrix composites degrade under the influence of UV radiation in the range of the 290-400 nm band. The degradation of polymer-matrix composites exposed to UV radiation is characterized by extensive aging of the epoxy matrix, resulting in deterioration of their mechanical properties. Glass fibers/epoxy resin composites were made by an out-of-autoclave method whereas a fiber optic sensor was placed between different layers of laminates.

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'Smart' structural health monitoring of composite materials with optical fiber sensors is becoming more and more important, especially in the aviation industry. This paper presents an overview of hybrid fiber-optic sensing systems based on scattering techniques, fiber Bragg gratings, interferometric techniques, and polarimetric methods in structural health monitoring. The main purpose of this manuscript is to analyze the possibilities of using hybrid sensors based on fiber optics to monitor composite structures, with a particular emphasis on aircraft structures.

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Two diffractive optical elements are used to create a compact raster THz scanning setup in reflective configuration. The first one focuses the radiation into the small focal spot on the sample, while the second one collects reflected radiation and focuses it on the detector. To assure small size of the setup and large apertures of optical elements, structures work in the off-axis geometry.

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Cardiac output during exercise increases by as much as fivefold in the untrained man, and by as much as eightfold in the elite athlete. Increasing venous return is a critical but much overlooked component of the physiological response to exercise. Cardiac disorders such as constrictive pericarditis, restrictive cardiomyopathy and pulmonary hypertension are recognised to impair preload and cause exercise limitation; however, the effects of peripheral venous obstruction on cardiac function have not been well described.

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Volume management is an essential component of anti-hypertensive therapy. Different volume phenotypes have been proposed. We sought to study the total blood volume (TBV), plasma volume (PV), and red blood cell volume (RBV) in hypertensive patients.

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Purpose Of Review: This review was undertaken to update readers on the field of therapeutic renal denervation for hypertension during the 2016 through 2018 period.

Recent Findings: After the failure of Symplicity HTN-3 to meet its top line objective, intense scrutiny revealed several possible concerns addressed by the newer investigations into the area of renal denervation. These included better device technology, more intense subject monitoring for off-protocol antihypertensive drug usage, and deeper penetration into the renal vasculature by the interventionist.

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Aims: Readmissions for heart failure (HF) are a major burden. We aimed to assess whether the extent of improvement in pulmonary fluid content (ΔPC) during HF hospitalization evaluated by lung impedance (LI), or indirectly by other clinical and laboratory parameters, predicts readmissions.

Methods And Results: The present study is based on pre-defined secondary analysis of the IMPEDANCE-HF extended trial comprising 266 HF patients at New York Heart Association Class II-IV and left ventricular ejection fraction ≤ 35% randomized to LI-guided or conventional therapy during long-term follow-up.

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Unlabelled: It has been postulated that catheter-based renal denervation (RDN) may lower blood pressure (BP) and improve severity of obstructive sleep apnea (OSA) in resistant hypertensive patients. The aim of our study (NCT01366625) was to investigate in a prospective randomized trial the effect of RDN on BP and clinical course of OSA. Sixty patients with true resistant hypertension coexisting with moderate-to-severe OSA (apnea/hypopnea index, ≥15) were randomly allocated to RDN group (30 patients) and to control group (30 patients).

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