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Antje Werblow Sarah Bolius Adriaan W. C. Dorresteijn Christian Melaun Sven Klimpel 《Parasitology research》2013,112(7):2495-2501
Culex torrentium is one of the most common mosquito species in Germany. Due to its sympatric occurrence as well as its similar morphological and ecological characteristics, it has often been confused with another common species, Culex pipiens. Both species are known to be potential vectors for different arboviruses (not only in Germany) with C. torrentium being a possible vector for Sindbis or Ockelbo virus. In our study, we analyzed the genetic variability in a 658 bp fragment of the cytochrome c oxidase subunit I gene (coxI) of C. torrentium, from nine localities in the Frankfurt/Rhine-Main Metropolitan Region. The results of our genetic survey indicate a higher genetic diversity in this gene region for C. torrentium than for the morphologically similar C. pipiens. Our findings may explain the difficulties in the past to find morphological characteristics that apply to all populations of C. torrentium, when attempting to separate them clearly from C. pipiens, by any other criteria than male genitalia. Being ornithophilic, possible hybrids between C. torrentium and the humanophilic C. pipiens biotype molestus, could potentially serve as important vectors for zoonotic diseases. Therefore, we recommend that greater emphasis is placed on the ecological characteristics, population structure, and the taxonomy of this often neglected species, in the future. 相似文献
44.
Pierre Lahoud Mostafa EzEldeen Thomas Beznik Holger Willems André Leite Adriaan Van Gerven Reinhilde Jacobs 《Journal of endodontics》2021,47(5):827-835
IntroductionTooth segmentation on cone-beam computed tomographic (CBCT) imaging is a labor-intensive task considering the limited contrast resolution and potential disturbance by various artifacts. Fully automated tooth segmentation cannot be achieved by merely relying on CBCT intensity variations. This study aimed to develop and validate an artificial intelligence (AI)-driven tool for automated tooth segmentation on CBCT imaging.MethodsA total of 433 Digital Imaging and Communications in Medicine images of single- and double-rooted teeth randomly selected from 314 anonymized CBCT scans were imported and manually segmented. An AI-driven tooth segmentation algorithm based on a feature pyramid network was developed to automatically detect and segment teeth, replacing manual user contour placement. The AI-driven tool was evaluated based on volume comparison, intersection over union, the Dice score coefficient, morphologic surface deviation, and total segmentation time.ResultsOverall, AI-driven and clinical reference segmentations resulted in very similar segmentation volumes. The mean intersection over union for full-tooth segmentation was 0.87 (±0.03) and 0.88 (±0.03) for semiautomated (SA) (clinical reference) versus fully automated AI-driven (F-AI) and refined AI-driven (R-AI) tooth segmentation, respectively. R-AI and F-AI segmentation showed an average median surface deviation from SA segmentation of 9.96 μm (±59.33 μm) and 7.85 μm (±69.55 μm), respectively. SA segmentations of single- and double-rooted teeth had a mean total time of 6.6 minutes (±76.15 seconds), F-AI segmentation of 0.5 minutes (±8.64 seconds, 12 times faster), and R-AI segmentation of 1.2 minutes (±33.02 seconds, 6 times faster).ConclusionsThis study showed a unique fast and accurate approach for AI-driven automated tooth segmentation on CBCT imaging. These results may open doors for AI-driven applications in surgical and treatment planning in oral health care. 相似文献
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Sander C. J. Verfaillie Sofie M. Adriaanse Maja A. A. Binnewijzend Marije R. Benedictus Rik Ossenkoppele Mike P. Wattjes Yolande A. L. Pijnenburg Wiesje M. van der Flier Adriaan A. Lammertsma Joost P. A. Kuijer Ronald Boellaard Philip Scheltens Bart N. M. van Berckel Frederik Barkhof 《European radiology》2015,25(10):3050-3059
47.
Silvia Morbelli Valentina Garibotto Elsmarieke Van De Giessen Javier Arbizu Gaël Chételat Alexander Drezgza Swen Hesse Adriaan A. Lammertsma Ian Law Sabina Pappata’ Pierre Payoux Marco Pagani On behalf of the European Association of Nuclear Medicine 《European journal of nuclear medicine and molecular imaging》2015,42(10):1487-1491
48.
Roel S. Driessen Wijnand J. Stuijfzand Pieter G. Raijmakers Ibrahim Danad James K. Min Jonathon A. Leipsic Amir Ahmadi Jagat Narula Peter M. van de Ven Marc C. Huisman Adriaan A. Lammertsma Albert C. van Rossum Niels van Royen Paul Knaapen 《Journal of the American College of Cardiology》2018,71(5):499-509
Background
Atherosclerotic plaque characteristics may affect downstream myocardial perfusion, as well as coronary lesion severity.Objectives
This study sought to evaluate the association between quantitative plaque burden and plaque morphology obtained using coronary computed tomography angiography (CTA) and quantitative myocardial perfusion obtained using [15O]H2O positron emission tomography (PET), as well as fractional flow reserve (FFR) derived invasively.Methods
Two hundred eight patients (63% men; age 58 ± 8.7 years) with suspected coronary artery disease were prospectively included. All patients underwent 256-slice coronary CTA, [15O]H2O PET, and invasive FFR measurements. Coronary CTA-derived plaque burden and morphology were assessed using commercially available software and compared with PET perfusion and FFR.Results
Atherosclerotic plaques were present in 179 patients (86%) and 415 of 610 (68%) evaluable coronary arteries. On a per-vessel basis, traditional coronary plaque burden indexes, such as plaque length and volume, minimal lumen area, and stenosis percentage, were significantly associated with impaired hyperemic myocardial blood flow (MBF) and FFR. In addition, morphological features, such as partially calcified plaques, positive remodeling (PR), and low attenuation plaque, displayed a negative impact on hyperemic MBF and FFR. Multivariable analysis revealed that the morphological feature of PR was independently related to impaired hyperemic MBF as well as an unfavorable FFR (p = 0.004 and p = 0.007, respectively), next to stenosis percentage (p = 0.001 and p < 0.001, respectively) and noncalcified plaque volume (p < 0.001 and p = 0.010, respectively).Conclusions
PR and noncalcified plaque volume are associated with detrimental downstream hyperemic myocardial perfusion and FFR, independent of lesion severity. 相似文献49.
[Purpose] The aim of this review was to present the available evidence for the effect of
McConnell taping on knee biomechanics in individuals with anterior knee pain. [Methods]
The PubMed, Medline, Cinahl, SPORTDiscus, PEDro and ScienceDirect electronic databases
were searched from inception until September 2014. Experimental research on knee
biomechanical or EMG outcomes of McConnell taping compared with no tape or placebo tape
were included. Two reviewers completed the searches, selected the full text articles, and
assessed the risk of bias of eligible studies. Authors were contacted for missing data.
[Results] Eight heterogeneous studies with a total sample of 220 were included in this
review. All of the studies had a moderate to low risk of bias. Pooling of data was
possible for three outcomes: average knee extensor moment, average VMO/VL ratio and
average VMO-VL onset timing. None of these outcomes revealed significant differences.
[Conclusion] The evidence is currently insufficient to justify routine use of the
McConnell taping technique in the treatment of anterior knee pain. There is a need for
more evidence on the aetiological pathways of anterior knee pain, level one evidence, and
studies investigating other potential mechanisms of McConnell taping.Key words: Patellofemoral pain syndrome, McConnell taping, Biomechanics 相似文献
50.
Simplified negative pressure wound therapy: clinical evaluation of an ultraportable,no‐canister system
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Donald A Hudson Kevin G Adams Adriaan Van Huyssteen Robin Martin Elizabeth M Huddleston 《International wound journal》2015,12(2):195-201
The aim of this study was to evaluate a prototype negative pressure wound therapy (NPWT) system that has been developed to simplify NPWT for wounds at the lower end of the acuity scale. The new device has a single preset pressure of ?80 mmHg, is single use and operates without an exudate canister. The disposable NPWT system (PICO?) was tested in a prospective, non‐comparative, multicentre clinical trial to assess device functionality and clinical acceptance. Twenty patients were recruited for a maximum treatment period of 14 days. The NPWT devices were fitted with data log chips to enable longitudinal assessment of negative pressure and leak rates during therapy. Sixteen (80%) patients had closed surgical wounds, two (10%) patients had traumatic wounds and two (10%) patients received meshed split thickness skin grafts. The mean study duration was 10·7 days (range: 5–14 days) and the mean dressing wear time per individual patient was 4·6 days (range: 2–11). Fifty‐five percent of wounds had closed by the end of the 14‐day study or earlier, with a further 40% of wounds progressing to closure. Real‐time pressure monitoring showed continuous delivery of NPWT. Three cases are discussed representing different wound locations and different patient factors that can increase the risk of post‐surgical complications. Clinical studies of the disposable NPWT system confirmed the ability of the simplified single‐use device to function consistently over the expected wear time. The anticipated reduced costs, ease of use and increased mobility of patients using this system may enable NPWT benefits to be available to a greater proportion of patients. 相似文献