202 research outputs found

    Prospective comparison of handheld ultrasound devices from different manufacturers with respect to B-scan quality and clinical significance for various abdominal sonography questions

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    Background: Handheld ultrasound (HHUS) devices have chiefly been deployed in emergency medicine, where they are considered a valid tool. The data situation is less clear in the case of internal questions in abdominal sonography. In our study, we investigate whether HHUS devices from different manufacturers differ in their B-scan quality, and whether any differences are relevant for the significance of an internal ultrasound examination. Method: The study incorporated eight HHUS devices from different manufacturers. Ultrasound videos of seven defined sonographic questions were recorded with all of the devices. The analogue recording of the same findings with a conventional high-end ultrasound (HEUS) device served as an evaluation criterion. Then, the corresponding findings were played side by side and evaluated by fourteen ultrasound experts using a point scale (5 points = very good; 1 point = insufficient). Results: The HHUS devices achieved relatively good results in terms of both the B-scan quality assessment and the ability to answer the clinical question, regardless of the manufacturer. One of the tested HHUS devices even achieved a significantly (p < 0.05) higher average points score in both the evaluation of B-scan quality and in the evaluation of clinical significance than the other devices. Regardless of the manufacturer, the HHUS devices performed best when determining the status/inferior vena cava volume and in the representation of ascites/free fluid. Conclusion: In various clinical abdominal sonography questions, HHUS systems can reliably reproduce findings, and are—while bearing their limitations in mind—an acceptable alternative to conventional HEUS systems. Irrespective of this, the present study demonstrated relevant differences in the B-scan quality of HHUS devices from different manufacturers

    The C-terminal head domain of Burkholderia pseudomallei BpaC has a striking hydrophilic core with an extensive solvent network

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    Gram-negative pathogens like Burkholderia pseudomallei use trimeric autotransporter adhesins such as BpaC as key molecules in their pathogenicity. Our 1.4 angstrom crystal structure of the membrane-proximal part of the BpaC head domain shows that the domain is exclusively made of left-handed parallel beta-roll repeats. This, the largest such structure solved, has two unique features. First, the core, rather than being composed of the canonical hydrophobic Ile and Val, is made up primarily of the hydrophilic Thr and Asn, with two different solvent channels. Second, comparing BpaC to all other left-handed parallel beta-roll structures showed that the position of the head domain in the protein correlates with the number and type of charged residues. In BpaC, only negatively charged residues face the solvent-in stark contrast to the primarily positive surface charge of the left-handed parallel beta-roll "type" protein, YadA. We propose extending the definitions of these head domains to include the BpaC-like head domain as a separate subtype, based on its unusual sequence, position, and charge. We speculate that the function of left-handed parallel beta-roll structures may differ depending on their position in the structure.Peer reviewe

    Prospective comparison of nine different handheld ultrasound (HHUS) devices by ultrasound experts with regard to B-scan quality, device handling and software in abdominal sonography

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    The HHUS market is very complex due to a multitude of equipment variants and several different device manufacturers. Only a few studies have compared different HHUS devices under clinical conditions. We conducted a comprehensive prospective observer study with a direct comparison of nine different HHUS devices in terms of B-scan quality, device handling, and software features under abdominal imaging conditions. Methods: Nine different HHUS devices (Butterfly iQ+, Clarius C3HD3, D5CL Microvue, Philips Lumify, SonoEye Chison, SonoSite iViz, Mindray TE Air, GE Vscan Air, and Youkey Q7) were used in a prospective setting by a total of 12 experienced examiners on the same subjects in each case and then assessed using a detailed questionnaire regarding B-scan quality, handling, and usability of the software. The evaluation was carried out using a point scale (5 points: very good; 1 point: insufficient). Results: In the overall evaluation, Vscan Air and SonoEye Chison achieved the best ratings. They achieved nominal ratings between “good” (4 points) and “very good” (5 points). Both devices differed significantly (p < 0.01) from the other seven devices tested. Among the HHUS devices, Clarius C3HD3 and Vscan Air achieved the best results for B-mode quality, D5CL Microvue achieved the best results for device handling, and SonoEye Chison and Vscan Air achieved the best results for software. Conclusions: This is the first comprehensive study to directly compare different HHUS devices in a head-to-head manner. While the majority of the tested devices demonstrated satisfactory performance, notable discrepancies were observed between them. In particular, the B-scan quality exhibited considerable variation, which may have implications for the clinical application of HHUS. The findings of this study can assist in the selection of an appropriate HHUS device for specific applications, considering the clinical objectives and acknowledging the inherent limitations

    Development and evaluation of a point-of-care ocular ultrasound curriculum for medical students : a proof-of-concept study

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    Background Point-of-care Ocular Ultrasound (POCOUS) has gained importance in emergency medicine and intensive care in recent years. This work aimed to establish and evaluate a dedicated ultrasound education program for learning POCOUS-specific skills during medical studies at a university hospital. Methods The blended learning-based program (6 teaching units) based on recent scientific publications and recommendations was developed for students in the clinical part of their medical studies. Experts and trainers consisted of physicians from the Ear-Nose-Throat, radiology, ophthalmology and neurology specialties as well as university educational specialists. Lecture notes containing digital video links for preparation was produced as teaching material. In total, 33 students participated in the study. The education program, including the teaching materials, motivation and subjective gain in competency, was evaluated with the aid of a questionnaire (7-point Likert response format). Objective learning success was assessed on the basis of pre- and post-tests. These covered the skill areas: “anatomical basics”, “ultrasound basics”, “understanding of cross-sectional images”, “normal findings” and “pathology recognition”. Results In the objective assessment of image interpretation, the participants improved significantly (p < 0.001) from pre- to post-test with a large effect size (Cohen’s d = 1.78, effect size r = 0.66). The evaluations revealed a high level of satisfaction with the course concept, teaching materials and the tutors. In addition, a high level of motivation was recorded in relation to continuing to study “ultrasound diagnostics” and “ophthalmologic diseases”. A significant (p < 0.01) positive gain was also achieved in terms of the subjective assessment of competency. This covers areas such as expertise, sonographic anatomy and performing a POCOUS examination as well as recognizing retinal detachment, globe perforation and increased optic nerve sheath diameter. Conclusion The results of this feasibility study show that medical students accept and support a POCOUS-specific education program and are able to develop a higher objective and subjective level of competency. Future transfer to other sites and larger groups of participants seems feasible

    Development and Integration of DOPS as Formative Tests in Head and Neck Ultrasound Education : Proof of Concept Study for Exploration of Perceptions

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    In Germany, progress assessments in head and neck ultrasonography training have been carried out mainly theoretically and lack standardisation. Thus, quality assurance and comparisons between certified courses from various course providers are difficult. This study aimed to develop and integrate a direct observation of procedural skills (DOPS) in head and neck ultrasound education and explore the perceptions of both participants and examiners. Five DOPS tests oriented towards assessing basic skills were developed for certified head and neck ultrasound courses on national standards. DOPS tests were completed by 76 participants from basic and advanced ultrasound courses (n = 168 documented DOPS tests) and evaluated using a 7-point Likert scale. Ten examiners performed and evaluated the DOPS after detailed training. The variables of “general aspects” (6.0 Scale Points (SP) vs. 5.9 SP; p = 0.71), “test atmosphere” (6.3 SP vs. 6.4 SP; p = 0.92), and “test task setting” (6.2 SP vs. 5.9 SP; p = 0.12) were positively evaluated by all participants and examiners. There were no significant differences between a basic and advanced course in relation to the overall results of DOPS tests (p = 0.81). Regardless of the courses, there were significant differences in the total number of points achieved between individual DOPS tests. DOPS tests are accepted by participants and examiners as an assessment tool in head and neck ultrasound education. In view of the trend toward “competence-based” teaching, this type of test format should be applied and validated in the future

    Cloud-Based Secure Logger for Medical Devices

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    A logger in the cloud capable of keeping a secure, time-synchronized and tamper-evident log of medical device and patient information allows efficient forensic analysis in cases of adverse events or attacks on interoperable medical devices. A secure logger as such must meet requirements of confidentiality and integrity of message logs and provide tamper-detection and tamper-evidence. In this paper, we propose a design for such a cloud-based secure logger using the Intel Software Guard Extensions (SGX) and the Trusted Platform Module (TPM). The proposed logger receives medical device information from a dongle attached to a medical device. The logger relies on SGX, TPM and standard encryption to maintain a secure communication channel even on an untrusted network and operating system. We also show that the logger is resilient against different kinds of attacks such as Replay attacks, Injection attacks and Eavesdropping attacks

    A blended learning approach for teaching thoracic radiology to medical students: a proof-of-concept study

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    IntroductionThe best way to impart knowledge to medical students is still unclear. Therefore, we designed a blended learning course in thoracic radiology including both “traditional” in-class time as well as online learning modules. The aims were (1) to investigate students’ attitudes toward this blended learning approach; and (2) to test whether it improved their knowledge about thoracic radiology.MethodsA prospective study was conducted at the local medical center; 156 fourth-year medical students completed this study. Before and after the course, students had to complete (1) questionnaires to investigate their attitudes (7-point Likert scale); and (2) an objective test to assess their knowledge (multiple-choice/free text questions; results as % of correct answers).ResultsRegarding (1), the course led to an improvement in all items compared to baseline, exemplary: interest in thoracic radiology (precourse 4.2 vs. 5.4 postcourse) and the fulfillment of students’ expressed requirements regarding the teaching content (4.5 precourse vs. 6.2 postcourse). Furthermore, the great majority (88%) of our participants wished for more online learning offerings in the future. Regarding (2), the course led to improved knowledge on the objective test (precourse: 40% vs. postcourse: 63% correct answers).ConclusionThis feasibility study showed the successful design and implementation of a blended learning approach in thoracic radiology. Furthermore, it revealed medical students’ positive attitudes toward this approach and showed an increased knowledge in thoracic radiology. Thus, such approaches might be used to enrich the teaching armamentarium in medical education and to further enhance interest and knowledge in thoracic diseases among medical students

    ADAM17 Inhibition Increases the Impact of Cisplatin Treatment in Ovarian Cancer Spheroids

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    Chemotherapy resistance is a major challenge in ovarian cancer (OvCa). Thus, novel treatment combinations are highly warranted. However, many promising drug candidates tested in two-dimensional (2D) cell culture have not proved successful in the clinic. For this reason, we analyzed our drug combination not only in monolayers but also in three-dimensional (3D) tumor spheroids. One potential therapeutic target for OvCa is A disintegrin and metalloprotease 17 (ADAM17). ADAM17 can be activated by chemotherapeutics, which leads to enhanced tumor growth due to concomitant substrate cleavage. Therefore, blocking ADAM17 during chemotherapy may overcome resistance. Here, we tested the effect of the ADAM17 inhibitor GW280264X in combination with cisplatin on ovarian cancer cells in 2D and 3D. In 2D, the effect on five cell lines was analyzed with two readouts. Three of these cell lines formed dense aggregates or spheroids (HEY, SKOV-3, and OVCAR-8) in 3D and the treatment effect was analyzed with a multicontent readout (cytotoxicity, viability, and caspase3/7 activation). We tested the combined therapy on tumor spheroids derived from primary patient cells. In 2D, we found a significant reduction in the half minimal (50%) inhibitory concentration (IC50) value of the combined treatment (GW280264X plus cisplatin) in comparison with cisplatin monotherapy in all five cell lines with both 2D readout assays (viability and caspase activation). In contrast, the combined treatment only showed an IC50 reduction in HEY and OVCAR-8 3D tumor spheroid models using caspase3/7 activity or CelltoxTM Green as the readout. Finally, we found an improved effect of GW280264X with cisplatin in tumor spheroids derived from patient samples. In summary, we demonstrate that ADAM17 inhibition is a promising treatment strategy in ovarian cancer

    Advanced 3D Textile Applications for the Building Envelope

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    Within the field of textile construction, textiles are traditionally used either as decorative elements in interior design or as flat textiles in tensile-stressed lightweight constructions (roofs, temporary buildings, etc.). Technical textiles made of glass or carbon fibers are now also used as steel substitutes in concrete construction. There, flat textiles are also used as lost formwork or shaping semi-finished products. Applications for 3D textiles and in particular spacer textiles have so far only been investigated as part of multilayer constructions in combination with other elements. Otherwise, there are no studies for their application potential in the roof and wall areas of buildings and as a starting structure for opaque and translucent components. The two research projects presented here, "ReFaTex" (adjustable spacer fabrics for solar shading devices) and "ge3TEX" (warp-knitted, woven and foamed spacer fabrics) illustrate for one thing the possibilities for using 3D textiles for the construction of movable and translucently variable solar protection elements in the building envelope. Otherwise they show how 3D textiles in combination with foamed materials can be transformed into opaque, lightweight, self-supporting and insulated wall and ceiling components in the building envelope. Both projects are designed experimentally and iteratively. The results are compared in a qualifying manner, the aim being not to quantify individual measured variables but to explore the development potential of textile construction for sustainable future components and to realize the first demonstrators. In the ReFaTex project, 1:1 demonstrators with different movement mechanisms for controlling the incidence of light were realized. In the ge3TEX project, 1:1 demonstrators made of three different textile and foam materials were added to form new single-origin composite components for ceiling elements. Both projects show the great application potential for 3D textiles in the construction industry

    The prevalence of effort-reward imbalance and its associations with working conditions, psychosocial resources and burden among health care workers during the COVID-19 pandemic: Results of the egePan-Voice study

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    ObjectiveThe association between a measure of effort-reward imbalance (ERI) and profession as well as gender in a sample of health care workers (HCW) during the first wave of the COVID-19 pandemic in Germany using the egePan-Voice study. In addition, we examined, which factors are associated with an effort-reward imbalance ratio (ERI ratio) &gt;1.MethodsIn a large sample of HCW (N = 6174) we assessed occupational stress with the short version of the effort-reward imbalance (ERI) questionnaire, working conditions, COVID-19-related problems and psychosocial resources (ENRICHD Social Support Inventory, ESSI; Sense of Coherence Scale, SOC-3 and optimism, SOP2).ResultsThe prevalence of a ERI ratio &gt;1 among HCW was 50.9%. The prevalence’s of an ERI ratio &gt;1 were statistically significant different between gender as well as the occupational profession. The proportion of women (51.8%) with ERI ratio &gt;1 was significantly higher than among men (47.8%). The highest ERI imbalance was found among nurses (62.8%), followed by medical technical assistants (MTA) (58.8%), while psychologists/psychotherapists revealed the lowest value (37.8%), followed by physicians (41.8%). In the total sample, most essential factors reported at this time for increased ERI ratio were: insufficient staff for the current work load, insufficient recovery, feeling insufficiently protected by measures taken by the hospital/the employer, high occupancy rate of the wards, insufficient trust in colleagues and being a nurse as compared with being a physician.ConclusionThe findings indicate a high proportion of HCW with effort-reward imbalance and substantial profession-related differences. Preventive interventions should be offered to vulnerable groups among the HCW to decrease the imbalance measured by work stress.</jats:sec
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