Browse
Submit Data
Databases
API
Help

Dataset Information

6 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

PDMS and DLC-coated unidirectional valves for artificial urinary sphincters: Opening performance after 126 days of immersion in urine.

ABSTRACT: In this work, unidirectional valves made of bare polydimethylsiloxane (PDMS) and PDMS provided with a micrometric diamond-like carbon (DLC) coating were fabricated and characterized, in terms of surface properties and opening pressure. The valve performance was also tested over 1250 repeated cycles of opening/closure in water, finding a slight decrease in the opening pressure after such cycles (10%) for the PDMS valves, while almost no variation for the PDMS + DLC ones. The valves were then immersed in urine for 126 days, evaluating the formation of encrustations and the trend of the opening pressure over time. Results showed that PDMS valves were featured by a thin layer of encrustations after 126 days, but the overall encrustation level was much smaller than the one shown by PDMS in static conditions. Furthermore, the opening pressure was almost not affected by such a thin layer of crystals. DLC-coated valves showed even less encrustations at the same time-point, with no significant loss of performance over time, although they were featured by a higher variability. These results suggest that most encrustations can be removed by the mechanical action of the valve during daily openings/closures. Such a self-cleaning behavior with respect to a static condition opens exciting scenarios for the long-term functionality of mobile devices operating in the urinary environment.

SUBMITTER: Mazzocchi T

PROVIDER: S-EPMC9298115 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

DLC-Coated Ferroelectric Membranes as Vascular Patches: Physico-Chemical Properties and Biocompatibility.

Project description:In this paper, the results on the fabrication of ferroelectric membranes as vascular patches with modified surfaces are presented. For the modification of a membrane surface contacting blood, DLC coating was deposited using the pulsed vacuum arc deposition technique. The physico-chemical properties and cytotoxicity of the membranes modified under various conditions were studied. It was found that DLC coatings do not affect membrane microstructure, preserving its crystal structure as well as its high strength and elongation. It was revealed that an increase in the capacitor storage voltage results in the rise in sp2- and sp-hybridized carbon concentration, which makes it possible to control the chemical structure and surface energy of the modified surface. The experiments with 3T3L1 fibroblasts showed no toxic effects of the materials extracts.

| S-EPMC8470059 | biostudies-literature

Successful long-term treatment of persistent pulmonary air leak in pneumocystis jirovecii pneumonia by unidirectional endobronchial valves.

Project description:Spontaneous pneumothorax is a rare complication of pneumocystis jirovecii pneumonia. We report a patient with pneumocystis jirovecii pneumonia and therapy-refractory, right-sided pneumothorax due to persistent air leak (PAL) despite prolonged chest tube placement and multiple pleurodesis attempts. Due to the patient's morbidity, we evaluated if the PAL can be sealed by unidirectional endobronchial valves (EBVs). After occlusion of the right upper lobe by a balloon catheter, the air leak flow-rate decreased from 800 ml/min to 250 ml/min. Zephyr EBVs (ZEBVs) were placed in the segmental right upper lobe bronchi and subsequently, a complete resolution of the pneumothorax was noted. During 30 months of follow-up, neither recurrence of pneumothorax nor any adverse events of EBV treatment were noted. We conclude that ZEBV placement might be an effective and well-tolerated treatment option for PAL secondary to pneumocystis jirovecii pneumonia with promising long-term results.

| S-EPMC6121160 | biostudies-literature

Disposable Polydimethylsiloxane (PDMS)-Coated Fused Silica Optical Fibers for Sampling Pheromones of Moths.

Project description:In the past decades, the sex pheromone composition in female moths has been analyzed by different methods, ranging from volatile collections to gland extractions, which all have some disadvantage: volatile collections can generally only be conducted on (small) groups of females to detect the minor pheromone compounds, whereas gland extractions are destructive. Direct-contact SPME overcomes some of these disadvantages, but is expensive, the SPME fiber coating can be damaged due to repeated usage, and samples need to be analyzed relatively quickly after sampling. In this study, we assessed the suitability of cheap and disposable fused silica optical fibers coated with 100 ?m polydimethylsiloxane (PDMS) by sampling the pheromone of two noctuid moths, Heliothis virescens and Heliothis subflexa. By rubbing the disposable PDMS fibers over the pheromone glands of females that had called for at least 15 minutes and subsequently extracting the PDMS fibers in hexane, we collected all known pheromone compounds, and we found a strong positive correlation for most pheromone compounds between the disposable PDMS fiber rubs and the corresponding gland extracts of the same females. When comparing this method to volatile collections and the corresponding gland extracts, we generally found comparable percentages between the three techniques, with some differences that likely stem from the chemical properties of the individual pheromone compounds. Hexane extraction of cheap, disposable, PDMS coated fused silica optical fibers allows for sampling large quantities of individual females in a short time, eliminates the need for immediate sample analysis, and enables to use the same sample for multiple chemical analyses.

| S-EPMC4988701 | biostudies-literature

PDMS Micropatterns Coated with PDA and RGD Induce a Regulatory Macrophage-like Phenotype.

Project description:Regulatory macrophages (Mreg) are a special cell type that present a potential therapeutic strategy for various inflammatory diseases. In vitro, Mreg generation mainly takes 7-10 days of treatment with chemicals, including cytokines. In the present study, we established a new approach for Mreg generation using a three-dimensional (3D) micropatterned polydimethylsiloxane (PDMS) surface coated with a natural biopolymer adhesive polydopamine (PDA) and the common cell adhesion peptide motif arginylglycylaspartic acid (RGD). The 3D PDMS surfaces were fabricated by photolithography and soft lithography techniques and were subsequently coated with an RGD+PDA mixture to form a surface that facilitates cell adhesion. Human monocytes (THP-1 cells) were cultured on different types of 2D or 3D micropatterns for four days, and the cell morphology, elongation, and Mreg marker expression were assessed using microscopic and flow cytometric analyses. The cells grown on the PDA+RGD-coated 3D micropatterns (20-µm width/20-µm space) exhibited the most elongated morphology and strongest expression levels of Mreg markers, such as CD163, CD206, CD209, CD274, MER-TK, TREM2, and DHRS9. The present study demonstrated that PDA+RGD-coated 3D PDMS micropatterns successfully induced Mreg-like cells from THP-1 cells within four days without the use of cytokines, suggesting a time- and cost-effective method to generate Mreg-like cells in vitro.

| S-EPMC10052727 | biostudies-literature

Creation of a PDMS Polymer Brush on SiO2-Based Nanoparticles by Surface-Initiated Ring-Opening Polymerization.

Project description:The incorporation of nanoparticles into soft matrices opens a broad spectrum of novel property combinations. However, one of the major challenges for these systems remains the compatibilization of particles with the surrounding matrix by proper surface functionalization. For silicon-based systems or liquid crystalline phases, polydimethylsiloxane (PDMS) brushes at the surface of particles increase the stability against particle agglomeration in such systems. Here, we report a novel approach for the functionalization of particles with a polysiloxane brush by surface-initiated ring-opening polymerization of a cyclosiloxane. For this purpose, surface hydroxy groups of silica and silica-coated hematite particles are used as initiators in combination with phosphazene bases as catalysts. The ring-chain equilibrium of a model-based solution polymerization is investigated in detail to find the appropriate reaction parameters. The corresponding molar masses are determined and compared by 1H-NMR and SEC measurements to confirm the underlying mechanism. In the resulting hybrid nanostructures, a covalently bound PDMS fraction is achieved up to 47 mass %.

| S-EPMC7240505 | biostudies-literature

PDMS-coated hypercrosslinked porous organic polymers modified <i>via</i> double postsynthetic acidifications for ammonia capture.

Project description:A hypercrosslinked porous organic polymer was modified by post-oxidation and post-sulfonation to obtain a porous platform with a high density of acidic groups. Such an acidified material exhibits record high NH3 adsorption capacity per surface area, fast adsorption rate, and recyclability at low desorption temperature. Noticeably, the coating of the polymer with PDMS represents a facile and efficient route to enable both a significant improvement of low-pressure NH3 adsorption capacity (∼40-fold enhancement; from 0.04 to 1.41 mmol g-1) with respect to the non-modified polymer at 500 ppm and hydrophobicity associated with the selective sorption of NH3 over water vapor (hydrophilic for the non-coated material). This material is easy to prepare, cost-effective, and scalable to mass production.

| S-EPMC6114995 | biostudies-literature

Precapillary sphincters maintain perfusion in the cerebral cortex.

Project description:Active nerve cells release vasodilators that increase their energy supply by dilating local blood vessels, a mechanism termed neurovascular coupling and the basis of BOLD functional neuroimaging signals. Here, we reveal a mechanism for cerebral blood flow control, a precapillary sphincter at the transition between the penetrating arteriole and first order capillary, linking blood flow in capillaries to the arteriolar inflow. The sphincters are encircled by contractile mural cells, which are capable of bidirectional control of the length and width of the enclosed vessel segment. The hemodynamic consequence is that precapillary sphincters can generate the largest changes in the cerebrovascular flow resistance of all brain vessel segments, thereby controlling capillary flow while protecting the downstream capillary bed and brain tissue from adverse pressure fluctuations. Cortical spreading depolarization constricts sphincters and causes vascular trapping of blood cells. Thus, precapillary sphincters are bottlenecks for brain capillary blood flow.

| S-EPMC6971292 | biostudies-literature

Characterization of DLC-A and DLC-B, two families of cytoplasmic dynein light chain subunits.

Project description:Cytoplasmic dynein is a minus-end-directed, microtubule-dependent motor composed of two heavy chains (approximately 530 kDa), three intermediate chains (approximately 74 kDa), and a family of approximately 52-61 kDa light chains. Although the approximately 530 kDa subunit contains the motor and microtubule binding domains of the complex, the functions of the smaller subunits are not known. Using two-dimensional gel electrophoresis and proteolytic mapping, we show here that the light chains are composed of two major families, a higher M(r) family (58, 59, 61 kDa; dynein light chain group A [DLC-A]) and lower M(r) family (52, 53, 55, 56 kDa; dynein light chain group B [DLC-B]). Dissociation of the cytoplasmic dynein complex with potassium iodide reveals that all light chain polypeptides are tightly associated with the approximately 530 kDa heavy chain, whereas the approximately 74 kDa intermediate chain polypeptides are more readily extracted. Treatment with alkaline phosphatase alters the mobility of four of the light chain polypeptides, indicating that these subunits are phosphorylated. Sequencing of a cDNA clone encoding one member of the DLC-A family reveals a predicted globular structure that is not homologous to any known protein but does contain numerous potential phosphorylation sites and a consensus nucleotide-binding motif.

| S-EPMC301080 | biostudies-other

Document Liveness Challenge Dataset (DLC-2021).

Project description:Various government and commercial services, including, but not limited to, e-government, fintech, banking, and sharing economy services, widely use smartphones to simplify service access and user authorization. Many organizations involved in these areas use identity document analysis systems in order to improve user personal-data-input processes. The tasks of such systems are not only ID document data recognition and extraction but also fraud prevention by detecting document forgery or by checking whether the document is genuine. Modern systems of this kind are often expected to operate in unconstrained environments. A significant amount of research has been published on the topic of mobile ID document analysis, but the main difficulty for such research is the lack of public datasets due to the fact that the subject is protected by security requirements. In this paper, we present the DLC-2021 dataset, which consists of 1424 video clips captured in a wide range of real-world conditions, focused on tasks relating to ID document forensics. The novelty of the dataset is that it contains shots from video with color laminated mock ID documents, color unlaminated copies, grayscale unlaminated copies, and screen recaptures of the documents. The proposed dataset complies with the GDPR because it contains images of synthetic IDs with generated owner photos and artificial personal information. For the presented dataset, benchmark baselines are provided for tasks such as screen recapture detection and glare detection. The data presented are openly available in Zenodo.

| S-EPMC9323793 | biostudies-literature

Production of an EP/PDMS/SA/AlZnO Coated Superhydrophobic Surface through an Aerosol-Assisted Chemical Vapor Deposition Process.

Project description:In this study, a superhydrophobic coating on glass has been prepared through a single-step aerosol-assisted chemical vapor deposition (AACVD) process. During the process, an aerosolized precursor containing polydimethylsiloxane, epoxy resin, and stearic acid functionalized Al-doped ZnO nanoparticles was deposited onto the glass at 350 °C. X-ray photoelectron spectroscopy, scanning electron microscopy, and atomic force microscopy showed that the precursor was successfully coated and formed a nano/microstructure (surface roughness: 378.0 ± 46.1 nm) on the glass surface. The coated surface had a water contact angle of 159.1 ± 1.2°, contact angle hysteresis of 2.2 ± 1.7°, and rolling off-angle of 1°, indicating that it was superhydrophobic. In the self-cleaning test of the coated surface at a tilted angle of 20°, it was shown that water droplets rolled and washed out dirt on the surface. The stability tests showed that the surface remained superhydrophobic after 120 h of exposure to ultraviolet (UV) irradiation and even after heat exposure at 350 °C. In addition, the surface was highly repellent to water solutions of pH 1-13. The results showed that the addition of the functionalized nanoparticles into the precursor allowed for the control of surface roughness and provided a simplified single-step fabrication process of the superhydrophobic surface. This provides valuable information for developing the manufacturing process for superhydrophobic surfaces.

| S-EPMC9245182 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data