prototype design
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A microfluidic cell capture device was designed, fabricated, evaluated by numerical simulations and validated experimentally. The cell capture device was designed with a minimal footprint compartment comprising internal micropillars with the goal to obtain a compact, integrated bioanalytical system. The design of the device was accomplished by computational fluid dynamics (CFD) simulations. Various microdevice designs were rapidly prototyped in poly-dimethylsiloxane using conventional soft lithograpy technique applying micropatterned SU-8 epoxy based negative photoresist as moulding replica. The numerically modeled flow characteristics of the cell capture device were experimentally validated by tracing and microscopic recording the flow trajectories using yeast cells. Finally, we give some perspectives on how CFD modeling can be used in the early stage of microfluidics-based cell capture device development.
BACKGROUND: Veno-arterial extracorporeal membrane oxygenation can be vital to support patients in severe or rapidly progressing cardiogenic shock. In cases of left ventricular distension, left ventricular decompression during veno-arterial extracorporeal membrane oxygenation may be a crucial factor influencing the patient outcome. Application of a double lumen arterial cannula for a left ventricular unloading is an alternative, straightforward method for left ventricular decompression during extracorporeal membrane oxygenation in a veno-arterial configuration. OBJECTIVES: The purpose of this article is to use a mathematical model of the human adult cardiovascular system to analyze the left ventricular function of a patient in cardiogenic shock supported by veno-arterial extracorporeal membrane oxygenation with and without the application of left ventricular unloading using a novel double lumen arterial cannula. METHODS: A lumped model of cardiovascular system hydraulics has been coupled with models of non-pulsatile veno-arterial extracorporeal membrane oxygenation, a standard venous cannula, and a drainage lumen of a double lumen arterial cannula. Cardiogenic shock has been induced by decreasing left ventricular contractility to 10% of baseline normal value. RESULTS: The simulation results indicate that applying double lumen arterial cannula during veno-arterial extracorporeal membrane oxygenation is associated with reduction of left ventricular end-systolic volume, end-diastolic volume, end-systolic pressure, and end-diastolic pressure. CONCLUSIONS: A double lumen arterial cannula is a viable alternative less invasive method for left ventricular decompression during veno-arterial extracorporeal membrane oxygenation. However, to allow for satisfactory extracorporeal membrane oxygenation flow, the cannula design has to be revisited.
- MeSH
- chirurgická dekomprese přístrojové vybavení metody MeSH
- design vybavení metody MeSH
- dospělí MeSH
- dysfunkce levé srdeční komory chirurgie MeSH
- kanyla * MeSH
- kardiogenní šok * patofyziologie chirurgie MeSH
- katetrizace centrálních vén přístrojové vybavení metody MeSH
- katetrizace metody MeSH
- lidé MeSH
- mimotělní membránová oxygenace * přístrojové vybavení metody MeSH
- počítačová simulace MeSH
- reprodukovatelnost výsledků MeSH
- srdeční komory patofyziologie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
A device for continuous infusion of microbubbles (MBs) 'Infucon' has been designed, constructed and tested on rabbits. The device prevents MBs from flotation and accumulation in the layer directly below the surface in the syringe injection during i.v. application. Homogenous i.v. application of MBs was tested on 16 male New Zealand White rabbits (average weight about 3.5 kg). Two sorts of MBs were used - a set of commercial SonoVue diagnostic microbubbles (Bracco) and pegylated DPPC microbubbles (PegMBs), which had been prepared in our laboratory. Sulphur hexafluoride was used as a filling gas. The application of MBs by continuous infusion via Infucon prolonged the ultrasound signal period in the heart of the rabbit to 12 min in comparison to about 1 min observed in bolus application. No adverse effects were observed on the tested rabbits after the MB application via Infucon. The principle employed in the prototype device Infucon could be used for development of the device intended for clinical applications.
- MeSH
- 1,2-dipalmitoylfosfatidylcholin chemie MeSH
- časové faktory MeSH
- fluorid sírový diagnostické užití MeSH
- fosfolipidy diagnostické užití MeSH
- intravenózní infuze MeSH
- králíci MeSH
- mikrobubliny diagnostické užití MeSH
- polyethylenglykoly chemie MeSH
- ultrasonografie metody MeSH
- zvířata MeSH
- Check Tag
- králíci MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- srovnávací studie MeSH
This paper presents a newly-designed and realized Invasive Blood Pressure (IBP) device for the simulation on patient's monitors. This device shows improvements and presents extended features with respect to a first prototype presented by the authors and similar systems available in the state-of-the-art. A peculiarity of the presented device is that all implemented features can be customized from the developer and from the point of view of the end user. The realized device has been tested, and its performances in terms of accuracy and of the back-loop measurement of the output for the blood pressure regulation utilization have been described. In particular, an accuracy of ±1 mmHg at 25 °C, on a range from -30 to 300 mmHg, was evaluated under different test conditions. The designed device is an ideal tool for testing IBP modules, for zero setting, and for calibrations. The implemented extended features, like the generation of custom waveforms and the Universal Serial Bus (USB) connectivity, allow use of this device in a wide range of applications, from research to equipment maintenance in clinical environments to educational purposes. Moreover, the presented device represents an innovation, both in terms of technology and methodologies: It allows quick and efficient tests to verify the proper functioning of IBP module of patients' monitors. With this innovative device, tests can be performed directly in the field and faster procedures can be implemented by the clinical maintenance personnel. This device is an open source project and all materials, hardware, and software are fully available for interested developers or researchers.
- MeSH
- design vybavení MeSH
- kalibrace MeSH
- krevní tlak fyziologie MeSH
- lidé MeSH
- měření krevního tlaku přístrojové vybavení metody MeSH
- monitorování fyziologických funkcí přístrojové vybavení metody MeSH
- monitory krevního tlaku * MeSH
- software MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Despite being present in many drugs, guanylhydrazones and semicarbazones are two functional groups that have been little investigated as potential therapeutic strategies for the treatment of Alzheimer's disease (AD). For this reason, we initiated the synthesis and evaluation of these compounds as potential anticholinesterase agents, aiming to offer new alternatives for drug development against AD. In the severe phase of AD butyrylcholinesterase (BChE) becomes the main enzyme responsible for the hydrolysis of acetylcholine (ACh). Therefore, in this project, we present the results of BChE inhibitory activity, enzyme kinetics, cytotoxicity, and molecular modeling studies for three guanylhydrazone and two semicarbazone derivatives that were previously synthesized and evaluated as acetylcholinesterase (AChE) inhibitors. Among the compounds tested, guanylhydrazones (1, 2, and 3) showed inhibitory activity against BChE, exhibiting a mixed non-competitive inhibition profile. Specifically, compound 2 (phenanthrenequinone) demonstrated superior inhibitory potency with an IC50 of 0.68 μM, compared to compound 1 (acridinone) with an IC50 of 3.87 μM, and compound 3 (benzodioxole) with an IC50 of 101.7 μM. In contrast, semicarbazones (4 and 5) showed no BChE inhibition up to the highest concentration tested (300 μM). Importantly, all five compounds were found to be non-cytotoxic. Our results suggest that these compounds have potential as drug prototypes targeting different phases of AD. Compounds 3, 4, and 5 may be more effective in the early phase, when AChE activity remains high; compound 1 could be useful in the intermediate phase; and compound 2 appears particularly promising for the severe phase, when BChE plays a more dominant role.
- MeSH
- acetylcholinesterasa metabolismus chemie MeSH
- Alzheimerova nemoc * farmakoterapie MeSH
- butyrylcholinesterasa metabolismus chemie MeSH
- cholinesterasové inhibitory * chemie farmakologie metabolismus terapeutické užití chemická syntéza MeSH
- hydrazony * chemie farmakologie MeSH
- kinetika MeSH
- lidé MeSH
- molekulární modely MeSH
- racionální návrh léčiv * MeSH
- semikarbazony * chemie farmakologie metabolismus MeSH
- simulace molekulového dockingu MeSH
- vztahy mezi strukturou a aktivitou MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
This article focuses on the design and implementation of a device aimed at monitoring gait dynamics. In clinical settings, gait dynamics are conventionally observed within specialized motion laboratories that rely on camera systems or pressure-sensitive floor mats. Unfortunately, these methods provide clinicians with only a temporally restricted perspective on a patient's health within the hospital environment. The objective of this study is to propose and develop a functional prototype of a measurement device that utilizes force-sensing resistors integrated into a sensorics insole placed within a shoe. By fusion of the 3D printing technology and force-sensing sensors, we developed a wearable prototype consisting of an instrumented insole and wireless data acquisition unit. This approach enables the capture of both static and dynamic parameters of gait, not only in clinical environments but also in non-hospital settings.
Reconstruction of the anatomic defect following extra-articular shoulder resection is a challenging problem, particularly in cases when function of the deltoid muscle and rotator cuff are compromised. Standard reconstruction techniques often result in either instability or rigidity. Constrained implants have been used to overcome these problems; however, they have been associated with a high rate of aseptic loosening. Recently, a novel double-constrained implant has been introduced, yielding promising functional results. Nonetheless, this implant exhibited a cosmetic defect related to protrusion of the humeral component that becomes apparent with time as result of surrounding muscle atrophy. An updated improved design of the implant has been developed to counteract this.We report the case of a 15-year-old patient who underwent an extra-articular (Malawer type V) shoulder resection due to osteosarcoma and received an innovated custom-made double-constrained implant. Moreover, we describe a new modification of the Malawer utilitarian approach to the shoulder girdle that enhances tumor visibility and allows safer dissection. The patient recovered well with satisfactory outcomes at 18 months follow-up, highlighting the potential benefits of this implant design and surgical approach.
- MeSH
- artroplastika ramenního kloubu * metody MeSH
- lidé MeSH
- mladiství MeSH
- nádory kostí * chirurgie patologie MeSH
- náhrada ramenního kloubu * MeSH
- osteosarkom * chirurgie patologie MeSH
- ověření koncepční studie MeSH
- prognóza MeSH
- protézy - design * MeSH
- ramenní kloub * chirurgie patologie MeSH
- výsledek terapie MeSH
- zákroky plastické chirurgie * metody MeSH
- Check Tag
- lidé MeSH
- mladiství MeSH
- mužské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- kazuistiky MeSH
Nosocomial infections are an important cause of morbi-mortality worldwide. The increase in the rate of resistance to conventional drugs in these microorganisms has stimulated the search for new therapeutic options. The nitro moiety (NO2) is an important pharmacophore of molecules with high anti-infective activity. We aimed to synthesize new nitro-derivates and to evaluate their antibacterial and anti-Candida potential in vitro. Five compounds [3-nitro-2-phenylchroman-4-ol (3); 3-nitro-2-phenyl-2H-chromene (4a); 3-nitro-2-(4-chlorophenyl)-2H-chromene (4b); 3-nitro-2-(4-fluorophenyl)-2H-chromene (4c), and 3-Nitro-2-(2,3-dichlorophenyl)-2H-chromene (4d)] were efficiently synthesized by Michael-aldol reaction of 2-hydroxybenzaldehyde with nitrostyrene, resulting in one β-nitro-alcohol (3) and four nitro-olefins (4a-4d). The antibacterial and anti-Candida potentials were evaluated by assaying minimal inhibitory concentration (MIC), minimum fungicidal concentration (MFC), and minimum bactericidal concentration (MBC). Mono-halogenated nitro-compounds (4b and 4c) showed anti-staphylococcal activity with MIC values of 15.6-62.5 μg/mL and MBC of 62.5 μg/mL. However, the activity against Gram-negative strains was showed to be considerably lower and our data suggests that this effect was associated with the outer membrane. Furthermore, nitro-compounds 4c and 4d presented activity against Candida spp. with MIC values ranging from 7.8-31.25 μg/mL and MFC of 15.6-500 μg/mL. In addition, these compounds were able to induce damage in fungal cells increasing the release of intracellular material, which was associated with actions on the cell wall independent of quantitative changes in chitin and β-glucan. Together, these findings show that nitro-compounds can be exploited as anti-staphylococcal and anti-Candida prototypes.
- MeSH
- antiinfekční látky chemická syntéza chemie farmakologie MeSH
- Bacteria účinky léků růst a vývoj MeSH
- Candida účinky léků růst a vývoj MeSH
- dusíkaté sloučeniny chemická syntéza chemie farmakologie MeSH
- infekce spojené se zdravotní péčí farmakoterapie mikrobiologie MeSH
- lidé MeSH
- mikrobiální testy citlivosti MeSH
- racionální návrh léčiv MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
V našem sdělení představujeme dosavadní výsledky společného výzkumu pracovišť Krajské nemocnice Liberec, a.s., a Technické univerzity v Liberci. Cílem projektu bylo sestrojit prototyp přístroje pro dvouosé měření mechanických vlastností lidské kůže in vivo. Dvouosé zatěžování umožní vyhodnocovat specifické parametry lidské kůže, které pro její anizotropii nelze zjistit při jednoosé tahové zkoušce. Prototyp byl nazván „BiEx“ (biaxial extensometer).
In our article we would like to present the results of joint research carried out at the Regional Hospital in Liberec and the Technical University of Liberec. The aim of this research was to design a prototype for biaxial measuring of mechanical properties of the human skin in vivo. Biaxial application of the load will allow for the evaluation of specific human skin parameters which cannot be determined during a uniaxial tensile test because of the skin anisotropy. This prototype was called “BiEx” (biaxial extensometer).
- Klíčová slova
- biomechanické vlastnosti kůže, dvouosý průtahoměr,
- MeSH
- biomechanika fyziologie MeSH
- financování organizované MeSH
- fyziologie kůže MeSH
- lidé MeSH
- pružnost MeSH
- Check Tag
- lidé MeSH
Acknowledging the importance of studies toward the development of measures against terrorism and bioterrorism, this study aims to contribute to the design of new prototypes of potential drugs against smallpox. Based on a former study, nine synthetic feasible prototypes of selective inhibitors for thymidylate kinase from Variola virus (VarTMPK) were designed and submitted to molecular docking, molecular dynamics simulations and binding energy calculations. The compounds are simplifications of two more complex scaffolds, with a guanine connected to an amide or alcohol through a spacer containing ether and/or amide groups, formerly suggested as promising for the design of selective inhibitors of VarTMPK. Our study showed that, despite the structural simplifications, the compounds presented effective energy values in interactions with VarTMPK and HssTMPK and that the guanine could be replaced by a simpler imidazole ring linked to a -NH2 group, without compromising the affinity for VarTMPK. It was also observed that a positive charge in the imidazole ring is important for the selectivity toward VarTMPK and that an amide group in the spacer does not contribute to selectivity. Finally, prototype 3 was pointed as the most promising to be synthesized and experimentally evaluated. Communicated by Ramaswamy H. Sarma.
- MeSH
- inhibitory enzymů chemie farmakologie terapeutické užití MeSH
- lidé MeSH
- ligandy MeSH
- nukleosidmonofosfátkinasa antagonisté a inhibitory chemie MeSH
- pravé neštovice farmakoterapie MeSH
- racionální návrh léčiv * MeSH
- simulace molekulární dynamiky MeSH
- simulace molekulového dockingu MeSH
- termodynamika MeSH
- virus varioly enzymologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH