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1.
Polymers (Basel) ; 16(8)2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38675060

RESUMO

This study investigates the adhesion properties of polycarbonate (PC) and liquid silicone rubbers (LSR) through surface activation using ultraviolet C (UVC) radiation. While self-adhesive LSRs adhere easily to certain thermoplastic composites such as polybutylene terephthalate (PBT) and polyamides (PAs), bonding to PC typically requires surface treatment due to the lack of compatible functional groups. Previous methods like plasma or flame treatment have been effective, but the use of UVC radiation for surface activation remains unexplored. Through experiments, it was found that UVC surface activation, particularly with ozone-generating lamps, significantly enhances the peel strength between PC and self-adhesive LSRs. The study evaluates the impact of different irradiation times and lamp configurations on peel resistance, surface energy, and composite stability. Results show that UVC/ozone (wavelengths 254 nm and 185 nm) activation increases peel resistance, with distinct differences observed between LSR types. Additionally, the study examines the stability of UVC activation over time and under various storage conditions, highlighting its effectiveness for up to 36 months at room temperature. Furthermore, the relationship between surface energy and peel strength is analyzed, finding that UVC/ozone activation increases surface energy but does not consistently correlate with improved adhesion. The study concludes with a comparison of UVC/ozone activation to alternative surface treatment methods, emphasizing its advantages such as cost-effectiveness and stability while considering limitations regarding substrate compatibility and occupational safety aspects. Overall, UVC/ozone surface activation presents a promising approach for enhancing adhesion in PC-LSR composite systems and holds potential for applications across various industries.

2.
medRxiv ; 2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-38076997

RESUMO

Most heritable diseases are polygenic. To comprehend the underlying genetic architecture, it is crucial to discover the clinically relevant epistatic interactions (EIs) between genomic single nucleotide polymorphisms (SNPs)1-3. Existing statistical computational methods for EI detection are mostly limited to pairs of SNPs due to the combinatorial explosion of higher-order EIs. With NeEDL (network-based epistasis detection via local search), we leverage network medicine to inform the selection of EIs that are an order of magnitude more statistically significant compared to existing tools and consist, on average, of five SNPs. We further show that this computationally demanding task can be substantially accelerated once quantum computing hardware becomes available. We apply NeEDL to eight different diseases and discover genes (affected by EIs of SNPs) that are partly known to affect the disease, additionally, these results are reproducible across independent cohorts. EIs for these eight diseases can be interactively explored in the Epistasis Disease Atlas (https://epistasis-disease-atlas.com). In summary, NeEDL is the first application that demonstrates the potential of seamlessly integrated quantum computing techniques to accelerate biomedical research. Our network medicine approach detects higher-order EIs with unprecedented statistical and biological evidence, yielding unique insights into polygenic diseases and providing a basis for the development of improved risk scores and combination therapies.

3.
Polymers (Basel) ; 15(19)2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37836021

RESUMO

The multicomponent injection molding of liquid silicone rubbers (LSR) with thermoplastics, such as polybutylene terephthalate (PBT) or polyamide (PA), is a state-of-the-art technique and is used in the manufacturing process for many components in the automotive industry and in the field of sanitary engineering. Standard thermoplastics, such as acrylonitrile butadiene styrene (ABS), cannot be bonded with silicone rubbers in injection molding because of their low heat deflection temperature. In this study, we investigated ABS grades approved for medical applications to show how dynamic mold heating and various pretreatment methods for thermoplastic surfaces can be used to produce ABS-LSR test specimens. In addition, such components' sterilization effect on the adhesive bond will be shown.

4.
Bioinformatics ; 39(11)2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37862243

RESUMO

MOTIVATION: The reconstruction of small key regulatory networks that explain the differences in the development of cell (sub)types from single-cell RNA sequencing is a yet unresolved computational problem. RESULTS: To this end, we have developed SCANet, an all-in-one package for single-cell profiling that covers the whole differential mechanotyping workflow, from inference of trait/cell-type-specific gene co-expression modules, driver gene detection, and transcriptional gene regulatory network reconstruction to mechanistic drug repurposing candidate prediction. To illustrate the power of SCANet, we examined data from two studies. First, we identify the drivers of the mechanotype of a cytokine storm associated with increased mortality in patients with acute respiratory illness. Secondly, we find 20 drugs for eight potential pharmacological targets in cellular driver mechanisms in the intestinal stem cells of obese mice. AVAILABILITY AND IMPLEMENTATION: SCANet is a free, open-source, and user-friendly Python package that can be seamlessly integrated into single-cell-based systems medicine research and mechanistic drug discovery.


Assuntos
Perfilação da Expressão Gênica , Software , Humanos , Animais , Camundongos , Análise de Sequência de RNA , Reposicionamento de Medicamentos , Análise da Expressão Gênica de Célula Única , Análise de Célula Única , Redes Reguladoras de Genes
5.
Polymers (Basel) ; 15(11)2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37299342

RESUMO

The influence of thermomechanical stress on the conductivity of indium tin oxide (ITO)-coated polycarbonate (PC) films was investigated. PC is the industry's standard material for window panes. ITO coatings on polyethylene terephthalate (PET) films are the main commercially available option; as such, most investigations refer to this combination. The investigations in this study aim to investigate the critical crack initiation strain at different temperatures and crack initiation temperatures for two different coating thicknesses and for a commercially available PET/ITO film for validation purposes. Additionally, the cyclic load was investigated. The results show the comparatively sensitive behavior of the PC/ITO films, with a crack initiation strain at room temperature of 0.3-0.4% and critical temperatures of 58 °C and 83 °C, with high variation depending on the film's thickness. Under thermomechanical loading, the crack initiation strain decreases with increasing temperatures.

6.
ArXiv ; 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37332567

RESUMO

In recent decades, the development of new drugs has become increasingly expensive and inefficient, and the molecular mechanisms of most pharmaceuticals remain poorly understood. In response, computational systems and network medicine tools have emerged to identify potential drug repurposing candidates. However, these tools often require complex installation and lack intuitive visual network mining capabilities. To tackle these challenges, we introduce Drugst.One, a platform that assists specialized computational medicine tools in becoming user-friendly, web-based utilities for drug repurposing. With just three lines of code, Drugst.One turns any systems biology software into an interactive web tool for modeling and analyzing complex protein-drug-disease networks. Demonstrating its broad adaptability, Drugst.One has been successfully integrated with 21 computational systems medicine tools. Available at https://drugst.one, Drugst.One has significant potential for streamlining the drug discovery process, allowing researchers to focus on essential aspects of pharmaceutical treatment research.

8.
Polymers (Basel) ; 15(9)2023 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-37177132

RESUMO

Electrochromic (EC) windows on glass for thermal and glare protection in buildings, often referred to as smart (dimmable) windows, are commercially available, along with rearview mirrors or windows in aircraft cabins. Plastic-based applications, such as ski goggles, visors and car windows, that require lightweight, three-dimensional (3D) geometry and high-throughput manufacturing are still under development. To produce such EC devices (ECDs), a flexible EC film could be integrated into a back injection molding process, where the films are processed into compact 3D geometries in a single automized step at a low processing time. Polycarbonate (PC) as a substrate is a lightweight and robust alternative to glass due to its outstanding optical and mechanical properties. In this study, an EC film on a PC substrate was fabricated and characterized for the first time. To achieve a highly transmissive and colorless bright state, poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) was used as the working electrode, while titanium dioxide (TiO2) was used as the counter electrode material. They were deposited onto ITO-coated PC films using dip- and slot-die coating, respectively. The electrodes were optically and electrochemically characterized. An ECD with a polyurethane containing gel electrolyte was investigated with regard to optical properties, switching speed and cycling behavior. The ECD exhibits a color-neutral and highly transmissive bright state with a visible light transmittance of 74% and a bluish-colored state of 64%, a fast switching speed (7 s/4 s for bleaching/coloring) and a moderately stable cycling behavior over 500 cycles with a decrease in transmittance change from 10%to 7%.

9.
Polymers (Basel) ; 15(6)2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36987226

RESUMO

A recently described flexible polyurethane electrolyte was artificially weathered at 25/50 °C and 50% r.h. in air and at 25 °C in a dry nitrogen atmosphere, each with and without UV irradiation. Different formulations and the polymer matrix, used as a reference, were weathered in order to investigate the influence of the amount of conductive lithium salt and the solvent propylene carbonate. The complete loss of the solvent at a standard climate was already observed after a few days, strongly influencing the conductivity and mechanical properties. The essential degradation mechanism appears to be the photo-oxidative degradation of the polyol's ether bonds, which leads to chain scission, oxidation products and negative changes in the mechanical and optical properties. A higher salt content has no effect on the degradation; however, the presence of propylene carbonate intensifies the degradation.

10.
Abdom Radiol (NY) ; 48(6): 2196-2205, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36941388

RESUMO

PURPOSE: Radiology global health opportunities are expanding as more hospitals in low- and middle-income countries utilize CT. This creates opportunities for global health program building, education, service, and research. This study determines the diagnostic yield and variety of abdominopelvic CT diagnoses for abdominal pain in a US academic medical center (UW) compared to a rural Kenyan teaching hospital (Tenwek). METHODS: A retrospective, cross-sectional sequential sample of 750 adults from both hospitals who underwent abdominopelvic CT for abdominal pain from February 2019 through July 2020 was obtained. Exclusion criteria were trauma, cancer staging, and recent hospitalization or surgery. Patient age, sex, comparison studies, use of contrast, known cancer diagnosis, and CT diagnoses were compared. Negative exam rate, acute abdomen diagnosis, and new cancer diagnosis were recorded. Statistical analysis was performed using R. RESULTS: 750 UW patients met inclusion criteria (mean age 53.3 ± 20 years; 442 women) and 750 Tenwek patients met inclusion criteria (mean age 52.5 ± 18 years; 394 women). 72% of UW patients had comparison imaging compared to 6% of Tenwek patients. 11% (83/750) of UW patients had a known cancer diagnosis compared to 1% (10/750) of Tenwek patients. 39% of UW patients had a negative exam compared to 23% of Tenwek patients (p < 0.001). 58% of UW patients had an acute abdomen diagnosis compared to 38% of Tenwek patients (p < 0.001). 10 of the 15 top acute abdomen diagnoses were shared, but in different order of frequency. Diagnoses unique to UW were diverticulitis, constipation, stercoral colitis, and epiploic appendagitis. Diagnoses unique to Tenwek were tuberculosis and hydatidosis. 3% of UW patients received a new cancer diagnosis (7/19 metastatic), compared to 40% of Tenwek patients (153/303 metastatic) (p < 0.001). CONCLUSION: For adults undergoing CT for abdominal pain, there are differences in the prevalence of abdominal pain diagnoses, new cancer diagnosis, and negative exam rate between the rural Kenyan teaching hospital and the US academic medical center.


Assuntos
Abdome Agudo , Colite Isquêmica , Adulto , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Quênia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Estudos Transversais , Dor Abdominal/diagnóstico por imagem , Hospitais de Ensino
11.
J Vasc Interv Radiol ; 34(5): 910-918, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36736821

RESUMO

PURPOSE: To compare electromagnetic navigation (EMN) with computed tomography (CT) fluoroscopy for guiding percutaneous biopsies in the abdomen and pelvis. MATERIALS AND METHODS: A retrospective matched-cohort design was used to compare biopsies in the abdomen and pelvis performed with EMN (consecutive cases, n = 50; CT-Navigation; Imactis, Saint-Martin-d'Hères, France) with those performed with CT fluoroscopy (n = 100). Cases were matched 1:2 (EMN:CT fluoroscopy) for target organ and lesion size (±10 mm). RESULTS: The population was well-matched (age, 65 vs 65 years; target size, 2.0 vs 2.1 cm; skin-to-target distance, 11.4 vs 10.7 cm; P > .05, EMN vs CT fluoroscopy, respectively). Technical success (98% vs 100%), diagnostic yield (98% vs 95%), adverse events (2% vs 5%), and procedure time (33 minutes vs 31 minutes) were not statistically different (P > .05). Operator radiation dose was less with EMN than with CT fluoroscopy (0.04 vs 1.2 µGy; P < .001), but patient dose was greater (30.1 vs 9.6 mSv; P < .001) owing to more helical scans during EMN guidance (3.9 vs 2.1; P < .001). CT fluoroscopy was performed with a mean of 29.7 tap scans per case. In 3 (3%) cases, CT fluoroscopy was performed with gantry tilt, and the mean angle out of plane for EMN cases was 13.4°. CONCLUSIONS: Percutaneous biopsies guided by EMN and CT fluoroscopy were closely matched for technical success, diagnostic yield, procedure time, and adverse events in a matched cohort of patients. EMN cases were more likely to be performed outside of the gantry plane. Radiation dose to the operator was higher with CT fluoroscopy, and patient radiation dose was higher with EMN. Further study with a wider array of procedures and anatomic locations is warranted.


Assuntos
Fenômenos Eletromagnéticos , Tomografia Computadorizada por Raios X , Humanos , Idoso , Estudos Retrospectivos , Biópsia , Tomografia Computadorizada por Raios X/efeitos adversos , Tomografia Computadorizada por Raios X/métodos , Abdome , Pelve , Fluoroscopia
12.
Polymers (Basel) ; 14(13)2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35808681

RESUMO

For the application in flexible electrochromic devices (ECDs) on plastic substrates, a new polyurethane-based gel electrolyte was manufactured. In this context, the curing behavior and the influence of the proportion of solvent and salt on the ion conductivity as well as the optical and mechanical properties were investigated. Furthermore, the stoichiometric ratio of the polyurethane matrix was varied to influence the ion conductivity. As an isocyanate component, the aliphatic difunctional polyisocyanate prepolymer, synthesized by Hexamethylen-1,6-diisocyanat (HDI), was chosen since the resulting polyurethane is considered to be particularly lightfast, color-stable and temperature-resistant and therefore frequently used for paints and coatings. As polyol a trifunctional polyetherpolyol was selected to form a wide-meshed crosslinked matrix to achieve a mechanically stable but flexible electrolyte, that enables the processing and bending of film-based ECDs. The additives amount and the matrix stoichiometric ratio affected the curing behavior and curability. The salt content had almost no influence on the measured properties in the chosen experimental space. Solvent content had a great influence on ion conductivity and mechanical properties. An understoichiometric ratio of the polyurethane matrix (0.85) increases the ion conductivity and the mechanical flexibility, but also the optical properties in a negative manner. The best specific ion conductivity with 10-5 S/cm was reached with an understoichiometric ratio of 0.85 and a high solvent content (30 wt%). Concluding, due to its high flexibility and transmittance, color neutrality and sufficient ion conductivity, the application of the researched electroyte in ECDs might be suitable. A demonstrator ECD was successfully manufactured and conducted.

14.
Polymers (Basel) ; 14(14)2022 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-35890582

RESUMO

Carbon fiber reinforced plastics (CFRP) bear a high potential in terms of electrical conductivity and its potential applications. A locally resolved electrical measurement method for these anisotropic materials is a key prerequisite for understanding the structural and manufacturing process-related interrelationships. The aim of this paper is to develop a measurement method that allows this to be achieved and also to investigate areas of overmolded metal contact pins in detail. CFRP samples with polyamide 6 and polycarbonate matrices were used, which were produced by using a custom-designed injection mold. In order to evaluate the measurement results and to correlate them to process related structural properties, reflected light microscopy and X-ray microtomography were used. Typical areas with significant fiber structures of assembly injection molded samples were electrically and structurally characterized to identify correlations. Among further results, the correlation of equipotential lines, acquired from the electrical analysis, with specific fiber orientations within the injection molded samples was demonstrated, fiber-poor areas were identified, and a beneficial influence of weld lines on contact resistances was determined.

15.
Nucleic Acids Res ; 50(W1): W138-W144, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35580047

RESUMO

Cancer is a heterogeneous disease characterized by unregulated cell growth and promoted by mutations in cancer driver genes some of which encode suitable drug targets. Since the distinct set of cancer driver genes can vary between and within cancer types, evidence-based selection of drugs is crucial for targeted therapy following the precision medicine paradigm. However, many putative cancer driver genes can not be targeted directly, suggesting an indirect approach that considers alternative functionally related targets in the gene interaction network. Once potential drug targets have been identified, it is essential to consider all available drugs. Since tools that offer support for systematic discovery of drug repurposing candidates in oncology are lacking, we developed CADDIE, a web application integrating six human gene-gene and four drug-gene interaction databases, information regarding cancer driver genes, cancer-type specific mutation frequencies, gene expression information, genetically related diseases, and anticancer drugs. CADDIE offers access to various network algorithms for identifying drug targets and drug repurposing candidates. It guides users from the selection of seed genes to the identification of therapeutic targets or drug candidates, making network medicine algorithms accessible for clinical research. CADDIE is available at https://exbio.wzw.tum.de/caddie/ and programmatically via a python package at https://pypi.org/project/caddiepy/.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Software , Oncogenes , Algoritmos , Mutação , Interações Medicamentosas , Reposicionamento de Medicamentos
17.
Abdom Radiol (NY) ; 47(8): 2567-2583, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34322727

RESUMO

Percutaneous ultrasound-guided biopsies have become the standard of practice for tissue diagnosis in the abdomen and pelvis for many sites including liver, kidney, abdominal wall, and peripheral nodal stations. Additional targets may appear difficult or impossible to safely biopsy by ultrasound due to interposed bowel loops/vasculature, deep positioning, association with the bowel, or concern for poor visibility; however, by optimizing technique, it is often possible to safely and efficiently use real-time ultrasound guidance for sampling targets that normally would be considered only appropriate for CT guided or surgical/endoscopic biopsy.


Assuntos
Biópsia Guiada por Imagem , Ultrassonografia de Intervenção , Abdome/diagnóstico por imagem , Abdome/patologia , Biópsia , Humanos , Biópsia Guiada por Imagem/métodos , Pelve/diagnóstico por imagem , Pelve/patologia , Ultrassonografia , Ultrassonografia de Intervenção/métodos
18.
J Vasc Interv Radiol ; 32(9): 1319-1327, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34229043

RESUMO

PURPOSE: To evaluate the outcomes of computed tomography (CT) fluoroscopy-guided core lung biopsies with emphasis on diagnostic yield, complications, and efficacy of parenchymal and pleural blood patching to avoid chest tube placement. METHODS: This is a single-center retrospective analysis of CT fluoroscopy-guided percutaneous core lung biopsies between 2006 and 2020. Parenchymal blood patching during introducer needle withdrawal was performed in 74% of cases as a preventive measure, and pleural blood patching was the primary salvage maneuver for symptomatic or growing pneumothorax in 60 of 83 (72.2%) applicable cases. RESULTS: A total of 1,029 patients underwent 1,112 biopsies (532 men; mean age, 66 years; 38.6%, history of emphysema; lesion size, 16.7 mm). The diagnostic yield was 93.6% (1,032/1,103). Fewer complications requiring intervention were observed in patients who underwent parenchymal blood patching (5.7% vs 14.2%, P < .001). Further intervention was required in 83 of 182 pneumothorax cases, which included the following: (a) pleural blood patch (5.4%, 60/1,112), (b) chest tube placement without a pleural blood patch attempt (1.5%, 17/1,112), and (c) simple aspiration (0.5%, 6/1,112). Pleural blood patch as monotherapy was successful in 83.3% (50/60) of cases without need for further intervention. The overall chest tube rate was 2.6% (29/1,112). Emphysema was the only significant risk factor for complications requiring intervention (P ≤ .001). CONCLUSIONS: Parenchymal blood patching during introducer needle withdrawal decreased complications requiring intervention. Salvage pleural blood patching reduced the frequency of chest tube placement for pneumothorax.


Assuntos
Pneumotórax , Radiografia Intervencionista , Idoso , Biópsia , Biópsia com Agulha de Grande Calibre , Humanos , Biópsia Guiada por Imagem , Pulmão/diagnóstico por imagem , Masculino , Pneumotórax/etiologia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
19.
NAR Cancer ; 3(1): zcaa042, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34316695

RESUMO

microRNAs (miRNAs) are post-transcriptional regulators involved in many biological processes and human diseases, including cancer. The majority of transcripts compete over a limited pool of miRNAs, giving rise to a complex network of competing endogenous RNA (ceRNA) interactions. Currently, gene-regulatory networks focus mostly on transcription factor-mediated regulation, and dedicated efforts for charting ceRNA regulatory networks are scarce. Recently, it became possible to infer ceRNA interactions genome-wide from matched gene and miRNA expression data. Here, we inferred ceRNA regulatory networks for 22 cancer types and a pan-cancer ceRNA network based on data from The Cancer Genome Atlas. To make these networks accessible to the biomedical community, we present SPONGEdb, a database offering a user-friendly web interface to browse and visualize ceRNA interactions and an application programming interface accessible by accompanying R and Python packages. SPONGEdb allows researchers to identify potent ceRNA regulators via network centrality measures and to assess their potential as cancer biomarkers through survival, cancer hallmark and gene set enrichment analysis. In summary, SPONGEdb is a feature-rich web resource supporting the community in studying ceRNA regulation within and across cancer types.

20.
Abdom Radiol (NY) ; 46(12): 5503-5508, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34086093

RESUMO

Traditional teaching methods in radiology education have not kept pace with advances in technology that foster successful transition into independent practice. This deficit has been exacerbated by the COVID-19 pandemic, as the need for social distancing and the introduction of hybrid staffing models have decreased the critical educational interactions at the reading room workstations between staff and trainees. By leveraging interactive, case-based learning, educators have the opportunity to bridge the substantial gap between basic pattern recognition and successfully making a diagnosis in independent practice. For the educator, this signals a shift away from perfect case selection and presenter authority, and toward the role of a guide facilitating an active case-based learning experience. This form of learning is best accompanied by guided interpretation and iterative feedback with the goal of developing similar levels of mastery and autonomy among graduating trainees. In this article, we present the tools and methods for incorporating interactive cases into existing and novel teaching materials to meet the unique challenges educators are facing today.


Assuntos
COVID-19 , Radiologia , Humanos , Pandemias , Radiografia , SARS-CoV-2
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