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1.
Wien Klin Wochenschr ; 135(15-16): 406-413, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37071203

RESUMO

INTRODUCTION: Eosinophilic esophagitis (EoE) is a chronic immune-mediated disease of the esophagus with increasing incidence and dysphagia as the main symptom. The management of suspected or known EoE by Austrian endoscopists has not been investigated yet. METHODS: A web-based survey with 13 questions about the management of EoE was sent to endoscopists via the Austrian Society of Gastroenterology and Hepatology (ÖGGH). RESULTS: A total of 222 endoscopists (74% gastroenterologists, 23% surgeons, and 2% pediatricians; 68% working in a hospital) from all 9 states participated. In patients with dysphagia but a normal appearing esophagus, 85% of respondents reported always taking biopsies; however, surgeons were less likely to obtain biopsies compared to gastroenterologists ("always" 69% vs. 90%, "sometimes" 29% vs. 10%, "never" 2% vs. 0%, p < 0.001). The approved budesonide orodispersible tablet is the preferred first-line drug used in EoE, ahead of proton pump inhibitors (PPI). Only 65% of participants monitor the patients by endoscopy and histology after 12 weeks of induction therapy, 26% do not continue maintenance therapy, and 22% monitor patients only when symptomatic. CONCLUSION: The vast majority of Austrian endoscopists adhere to the European and US guidelines in cases of suspected EoE. In contrast, despite the chronic disease course, a significant percentage of providers indicate not to use maintenance therapy and monitor the patients routinely.


Assuntos
Transtornos de Deglutição , Esofagite Eosinofílica , Humanos , Esofagite Eosinofílica/diagnóstico , Esofagite Eosinofílica/epidemiologia , Esofagite Eosinofílica/terapia , Transtornos de Deglutição/tratamento farmacológico , Transtornos de Deglutição/etiologia , Áustria , Inquéritos e Questionários , Inibidores da Bomba de Prótons/uso terapêutico
2.
Nat Commun ; 13(1): 5048, 2022 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-36030264

RESUMO

Tool based manufacturing processes like injection moulding allow fast and high-quality mass-market production, but for optical polymer components the production of the necessary tools is time-consuming and expensive. In this paper a process to fabricate metal-inserts for tool based manufacturing with smooth surfaces via a casting and replication process from fused silica templates is presented. Bronze, brass and cobalt-chromium could be successfully replicated from shaped fused silica replications achieving a surface roughnesses of Rq 8 nm and microstructures in the range of 5 µm. Injection moulding was successfully performed, using a commercially available injection moulding system, with thousands of replicas generated from the same tool. In addition, three-dimensional bodies in metal could be realised with 3D-Printing of fused silica casting moulds. This work thus represents an approach to high-quality moulding tools via a scalable facile and cost-effective route surpassing the currently employed cost-, labour- and equipment-intensive machining techniques.

3.
Tomography ; 8(4): 1678-1689, 2022 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-35894005

RESUMO

(1) This study evaluates the impact of an AI denoising algorithm on image quality, diagnostic accuracy, and radiological workflows in pediatric chest ultra-low-dose CT (ULDCT). (2) Methods: 100 consecutive pediatric thorax ULDCT were included and reconstructed using weighted filtered back projection (wFBP), iterative reconstruction (ADMIRE 2), and AI denoising (PixelShine). Place-consistent noise measurements were used to compare objective image quality. Eight blinded readers independently rated the subjective image quality on a Likert scale (1 = worst to 5 = best). Each reader wrote a semiquantitative report to evaluate disease severity using a severity score with six common pathologies. The time to diagnosis was measured for each reader to compare the possible workflow benefits. Properly corrected mixed-effects analysis with post-hoc subgroup tests were used. Spearman's correlation coefficient measured inter-reader agreement for the subjective image quality analysis and the severity score sheets. (3) Results: The highest noise was measured for wFBP, followed by ADMIRE 2, and PixelShine (76.9 ± 9.62 vs. 43.4 ± 4.45 vs. 34.8 ± 3.27 HU; each p < 0.001). The highest subjective image quality was measured for PixelShine, followed by ADMIRE 2, and wFBP (4 (4−5) vs. 3 (4−5) vs. 3 (2−4), each p < 0.001) with good inter-rater agreement (r ≥ 0.790; p ≤ 0.001). In diagnostic accuracy analysis, there was a good inter-rater agreement between the severity scores (r ≥ 0.764; p < 0.001) without significant differences between severity score items per reconstruction mode (F (5.71; 566) = 0.792; p = 0.570). The shortest time to diagnosis was measured for the PixelShine datasets, followed by ADMIRE 2, and wFBP (2.28 ± 1.56 vs. 2.45 ± 1.90 vs. 2.66 ± 2.31 min; F (1.000; 99.00) = 268.1; p < 0.001). (4) Conclusions: AI denoising significantly improves image quality in pediatric thorax ULDCT without compromising the diagnostic confidence and reduces the time to diagnosis substantially.


Assuntos
Interpretação de Imagem Radiográfica Assistida por Computador , Tomografia Computadorizada por Raios X , Inteligência Artificial , Criança , Humanos , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tórax , Tomografia Computadorizada por Raios X/métodos , Fluxo de Trabalho
4.
Adv Sci (Weinh) ; 9(31): e2204385, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36057994

RESUMO

Transparent ceramics like magnesium aluminate spinel (MAS) are considered the next step in material evolution showing unmatched mechanical, chemical and physical resistance combined with high optical transparency. Unfortunately, transparent ceramics are notoriously difficult to shape, especially on the microscale. Therefore, a thermoplastic MAS nanocomposite is developed that can be shaped by polymer injection molding at high speed and precision. The nanocomposite is converted to dense MAS by debinding, pre-sintering, and hot isostatic pressing yielding transparent ceramics with high optical transmission up to 84 % and high mechanical strength. A transparent macroscopic MAS components with wall thicknesses up to 4 mm as well as microstructured components with single micrometer resolution are shown. This work makes transparent MAS ceramics accessible to modern high-throughput polymer processing techniques for fast and cost-efficient manufacturing of macroscopic and microstructured components enabling a plethora of potential applications from optics and photonics, medicine to scratch and break-resistant transparent windows for consumer electronics.


Assuntos
Cerâmica , Nanocompostos , Polímeros
5.
Adv Sci (Weinh) ; 8(23): e2103180, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34668342

RESUMO

In recent years, additive manufacturing (AM) of glass has attracted great interest in academia and industry, yet it is still mostly limited to liquid nanocomposite-based approaches for stereolithography, two-photon polymerization, or direct ink writing. Melt-extrusion-based processes, such as fused deposition modeling (FDM), which will allow facile manufacturing of large thin-walled components or simple multimaterial printing processes, are so far inaccessible for AM of transparent fused silica glass. Here, melt-extrusion-based AM of transparent fused silica is introduced by FDM and fused feedstock deposition (FFD) using thermoplastic silica nanocomposites that are converted to transparent glass using debinding and sintering. This will enable printing of previously inaccessible glass structures like high-aspect-ratio (>480) vessels with wall thicknesses down to 250 µm, delicate parts including overhanging features using polymer support structures, as well as dual extrusion for multicolored glasses.

6.
Tomography ; 8(1): 22-32, 2021 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-35076602

RESUMO

(1) To explore the potential impact of an AI dual-energy CT (DECT) prototype on decision making and workflows by investigating its capabilities to differentiate COVID-19 from immunotherapy-related pneumonitis. (2) Methods: From 3 April 2020 to 12 February 2021, DECT from biometrically matching patients with COVID-19, pneumonitis, and inconspicuous findings were selected from our clinical routine. Three blinded readers independently scored each pulmonary lobe analogous to CO-RADS. Inter-rater agreement was determined with an intraclass correlation coefficient (ICC). Averaged perfusion metrics per lobe (iodine uptake in mg, volume without vessels in ml, iodine concentration in mg/mL) were extracted using manual segmentation and an AI DECT prototype. A generalized linear mixed model was used to investigate metric validity and potential distinctions at equal CO-RADS scores. Multinomial regression measured the contribution "Reader", "CO-RADS score", and "perfusion metrics" to diagnosis. The time to diagnosis was measured for manual vs. AI segmentation. (3) Results: We included 105 patients (62 ± 13 years, mean BMI 27 ± 2). There were no significant differences between manually and AI-extracted perfusion metrics (p = 0.999). Regardless of the CO-RADS score, iodine uptake and concentration per lobe were significantly higher in COVID-19 than in pneumonitis (p < 0.001). In regression, iodine uptake had a greater contribution to diagnosis than CO-RADS scoring (Odds Ratio (OR) = 1.82 [95%CI 1.10-2.99] vs. OR = 0.20 [95%CI 0.14-0.29]). The AI prototype extracted the relevant perfusion metrics significantly faster than radiologists (10 ± 1 vs. 15 ± 2 min, p < 0.001). (4) Conclusions: The investigated AI prototype positively impacts decision making and workflows by extracting perfusion metrics that differentiate COVID-19 from visually similar pneumonitis significantly faster than radiologists.


Assuntos
COVID-19 , Inteligência Artificial , Humanos , Imunoterapia , Pulmão/diagnóstico por imagem , Perfusão , Estudos Retrospectivos , SARS-CoV-2 , Tomografia Computadorizada por Raios X , Fluxo de Trabalho
7.
Adv Mater ; 33(37): e2101992, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34337801

RESUMO

Platinum (Pt) is an interesting material for many applications due to its high chemical resilience, outstanding catalytic activity, high electrical conductivity, and high melting point. However, microstructuring and especially 3D microstructuring of platinum is a complex process, based on expensive and specialized equipment often suffering from very slow processing speeds. In this work, organic-inorganic photoresins, which can be structured using direct optical lithography as well as two-photon lithography (TPL) with submicrometer resolution and high-throughput is presented. The printed structures are subsequently converted to high-purity platinum using thermal debinding of the binder and reduction of the salt. With this technique, complex 3D structures with a 3D resolution of 300 nm were fabricated. At a layer thickness of 35 nm, the patterns reach a high conductivity of 67% compared to bulk platinum. Microheaters, thermocouple sensors as well as a Lab-on-a-Chip system are presented as exemplary applications. This technology will enable a broad range of application from electronics, sensing and heating elements to 3D photonics and metamaterials.

8.
Micromachines (Basel) ; 12(11)2021 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-34832759

RESUMO

Polystyrene (PS) is one of the most commonly used thermoplastic materials worldwide and plays a ubiquitous role in today's biomedical and life science industry and research. The main advantage of PS lies in its facile processability, its excellent optical and mechanical properties, as well as its biocompatibility. However, PS is only rarely used in microfluidic prototyping, since the structuring of PS is mainly performed using industrial-scale replication processes. So far, microfluidic chips in PS have not been accessible to rapid prototyping via 3D printing. In this work, we present, for the first time, 3D printing of transparent PS using fused deposition modeling (FDM). We present FDM printing of transparent PS microfluidic channels with dimensions as small as 300 µm and a high transparency in the region of interest. Furthermore, we demonstrate the fabrication of functional chips such as Tesla-mixer and mixer cascades. Cell culture experiments showed a high cell viability during seven days of culturing, as well as enabling cell adhesion and proliferation. With the aid of this new PS prototyping method, the development of future biomedical microfluidic chips will be significantly accelerated, as it enables using PS from the early academic prototyping all the way to industrial-scale mass replication.

9.
Science ; 372(6538): 182-186, 2021 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-33833122

RESUMO

Glass is one of the most relevant high-performance materials that has the benefit of a favorable environmental footprint compared with that of other commodity materials. Despite the advantageous properties of glasses, polymers are often favored because they can be processed using scalable industrial replication techniques like injection molding (IM). Glasses are generally processed through melting, which is both energy intensive and technologically challenging. We present a process for glassworks using high-throughput IM of an amorphous silicon dioxide nanocomposite that combines established process technologies and low-energy sintering. We produce highly transparent glass using classical IM and sintering, allowing for a potentially substantial reduction in energy consumption. Our strategy merges polymer and glass processing, with substantial implications for glass utilization.

10.
Micromachines (Basel) ; 11(9)2020 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-32961823

RESUMO

Polymethylmethacrylate (PMMA) is one of the most important thermoplastic materials and is a widely used material in microfluidics. However, PMMA is usually structured using industrial scale replication processes, such as hot embossing or injection molding, not compatible with rapid prototyping. In this work, we demonstrate that microfluidic chips made from PMMA can be 3D printed using fused deposition modeling (FDM). We demonstrate that using FDM microfluidic chips with a minimum channel cross-section of ~300 µm can be printed and a variety of different channel geometries and mixer structures are shown. The optical transparency of the chips is shown to be significantly enhanced by printing onto commercial PMMA substrates. The use of such commercial PMMA substrates also enables the integration of PMMA microstructures into the printed chips, by first generating a microstructure on the PMMA substrates, and subsequently printing the PMMA chip around the microstructure. We further demonstrate that protein patterns can be generated within previously printed microfluidic chips by employing a method of photobleaching. The FDM printing of microfluidic chips in PMMA allows the use of one of microfluidics' most used industrial materials on the laboratory scale and thus significantly simplifies the transfer from results gained in the lab to an industrial product.

11.
Emerg Infect Dis ; 14(12): 1855-61, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19046507

RESUMO

A novel bluetongue virus (BTV) termed Toggenburg orbivirus (TOV) was detected in goats from Switzerland by using real-time reverse transcription-PCR. cDNA corresponding to the complete sequence of 7 of 10 double-stranded RNA segments of the viral genome was amplified by PCR and cloned into a plasmid vector. Five clones for each genome segment were sequenced to determine a consensus sequence. BLAST analysis and dendrogram construction showed that TOV is closely related to BTV, although some genome segments are distinct from the 24 known BTV serotypes. Maximal sequence identity to any BTV ranged from 63% (segment 2) to 79% (segments 7 and 10). Because the gene encoding outer capsid protein 2 (VP2), which determines the serotype of BTV, is placed within the BTV serogroup, we propose that TOV represents an unknown 25th serotype of BTV.


Assuntos
Vírus Bluetongue/classificação , Cabras/virologia , Animais , DNA Complementar , Dados de Sequência Molecular , Orbivirus/classificação , Orbivirus/genética , Orbivirus/isolamento & purificação , Filogenia , Reação em Cadeia da Polimerase , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Sorotipagem , Suíça
12.
Vet Microbiol ; 176(1-2): 97-108, 2015 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-25623013

RESUMO

Schmallenberg virus (SBV), an arthropod-borne orthobunyavirus was first detected in 2011 in cattle suffering from diarrhea and fever. The most severe impact of an SBV infection is the induction of malformations in newborns and abortions. Between 2011 and 2013 SBV spread throughout Europe in an unprecedented epidemic wave. SBV contains a tripartite genome consisting of the three negative-sense RNA segments L, M, and S. The virus is usually isolated from clinical samples by inoculation of KC (insect) or BHK-21 (mammalian) cells. Several virus passages are required to allow adaptation of SBV to cells in vitro. In the present study, the porcine SK-6 cell line was used for isolation and passaging of SBV. SK-6 cells proved to be more sensitive to SBV infection and allowed to produce higher titers more rapidly as in BHK-21 cells after just one passage. No adaptation was required. In order to determine the in vivo genetic stability of SBV during an epidemic spread of the virus the nucleotide sequence of the genome from seven SBV field isolates collected in summer 2012 in Switzerland was determined and compared to other SBV sequences available in GenBank. A total of 101 mutations, mostly transitions randomly dispersed along the L and M segment were found when the Swiss isolates were compared to the first SBV isolated late 2011 in Germany. However, when these mutations were studied in detail, a previously described hypervariable region in the M segment was identified. The S segment was completely conserved among all sequenced SBV isolates. To assess the in vitro genetic stability of SBV, three isolates were passage 10 times in SK-6 cells and sequenced before and after passaging. Between two and five nt exchanges per genome were found. This low in vitro mutation rate further demonstrates the suitability of SK-6 cells for SBV propagation.


Assuntos
Infecções por Bunyaviridae/veterinária , Doenças dos Bovinos/virologia , Orthobunyavirus/genética , Animais , Infecções por Bunyaviridae/epidemiologia , Infecções por Bunyaviridae/virologia , Bovinos , Doenças dos Bovinos/epidemiologia , Linhagem Celular , Europa (Continente)/epidemiologia , Feminino , Mutação , Gravidez , Suínos
13.
J Virol Methods ; 165(2): 325-9, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20219538

RESUMO

Toggenburg Orbivirus (TOV) has been detected recently in healthy goats in Switzerland. The virus is related closely to bluetongue virus (BTV) and is considered tentatively as a 25th serotype of BTV. Upon detection of additional TOV-positive goats in Switzerland, Germany, and Italy, these TOV isolates were characterized genetically by partial sequencing of the viral genome segment 2 which encodes VP2, the major outer capsid protein of orbiviruses. A TOV-specific RT-qPCR was developed, targeting conserved areas within segment 2. Since TOV cannot be propagated up to now outside its natural host, a synthetic positive control for the RT-qPCR was constructed by cloning the entire coding region of segment 2 and subsequent in vitro transcription of RNA from both ends to obtain double-stranded RNA. The TOV-specific RT-qPCR was able to detect as few as 30 dsRNA copies and proved to be equally sensitive as a pan BTV assay that was shown previously to have a detection limit of 0.001 TCID(50).


Assuntos
Genoma Viral/genética , Doenças das Cabras/diagnóstico , Orbivirus/isolamento & purificação , Infecções por Reoviridae/veterinária , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Animais , Sequência de Bases , Doenças das Cabras/virologia , Cabras , Dados de Sequência Molecular , Orbivirus/classificação , Orbivirus/genética , Filogenia , Infecções por Reoviridae/diagnóstico , Infecções por Reoviridae/virologia , Proteínas Estruturais Virais/genética
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