Direct Blood Cell Flow Imaging in Microvascular Networks.

Blood flow dynamics in microvascular networks are intimately related to the health of tissues and organs. While numerous imaging modalities and techniques have been developed to assess blood flow dynamics for various applications, their utilization has been hampered by limited imaging speed and indirect quantification of blood flow dynamics. Here, direct blood cell flow imaging (DBFI) is demonstrated that provides visualization of individual motions of blood cells over a field of 0.71 mm × 1.42 mm with a time resolution of 0.69 ms (1450 frames s-1 ) without using any exogenous agents. DBFI enables precise dynamic analysis of blood cell flow velocities and fluxes in various vessels over a large field, from capillaries to arteries and veins, with unprecedented time resolution. Three exemplary applications of DBFI, quantification of blood flow dynamics of 3D vascular networks, analysis of heartbeat induced blood flow dynamics, and analysis of blood flow dynamics of neurovascular coupling, illustrate the potential of this new imaging technology.

Use of video-based telehealth services using a mobile app for workers in underserved areas during the COVID-19 pandemic: A prospective observational study.

BACKGROUND: The COVID-19 pandemic has limited face-to-face treatment, triggering a change in the structure of existing healthcare services. Unlike other groups, workers in underserved areas have relatively poor access to healthcare. OBJECTIVE: This study aimed to investigate the effects of video-based telehealth services using a mobile personal health record (PHR) app for vulnerable workers with metabolic risk factors. METHODS: A prospective observational study was conducted with 117 participants and 27 healthcare professionals for 16 weeks. Participants visited the research institution three times (at weeks 1, 8, and 16) and underwent health check-ups and used various features of the mobile PHR app. Healthcare professionals observed the participants's data using the monitoring system and performed appropriate interventions. The primary outcome measures were to evaluate the effects of services on changes in the participants' metabolic risk factors, and secondary outcome measures were to analyze changes in the participants' lifestyle and service satisfaction, and to observe service use through usage logs. One-way repeated measures ANOVA and Scheffé's test were performed to observe changes in participants' health status and lifestyle, and a paired t-test was performed to analyze changes in service satisfaction. Finally, in-depth interviews with healthcare professionals were performed using semi-structured questionnaires to understand service providers' perspectives after the end of the study. RESULTS: Systolic blood pressure (F = 7.32, P <.001), diastolic blood pressure (F = 11.30, P <.001), body weight (F = 29.53, P <.001), BMI (F = 17.31, P <.001), waist circumference (F = 17.33, P <.001), fasting blood glucose (F = 5.11, P =.007), and triglycerides (F = 4.66, P =.01) showed significant improvements with time points, whereas high-density lipoprotein cholesterol (F = 3.35, P =.067) did not. The dietary score (F = 3.26, P =.04) showed a significant improvement with time points, whereas physical activity (F = 1.06, P =.34) did not. In terms of service satisfaction, only lifestyle improvement (P <.001) showed a significant difference. COVID-19 has affected the performance of healthcare professionals, thereby changing the perspectives toward healthcare technology services. CONCLUSIONS: We evaluated the effectiveness of video-based telehealth services supporting workers' health status and lifestyle interventions using healthcare technologies such as the mobile PHR app, tele-monitoring, and video teleconsultation. Our results indicate that as a complementary means, its utility can be expanded in the field of occupational safety and health to overcome the limitations of face-to-face treatment due to COVID-19 in the future.

Development and Evaluation of AccuPower COVID-19 Multiplex Real-Time RT-PCR Kit and AccuPower SARS-CoV-2 Multiplex Real-Time RT-PCR Kit for SARS-CoV-2 Detection in Sputum, NPS/OPS, Saliva and Pooled Samples.

Rapid and accurate detection of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is essential for the successful control of the current global COVID-19 pandemic. The real-time reverse transcription polymerase chain reaction (Real-time RT-PCR) is the most widely used detection technique. This research describes the development of two novel multiplex real-time RT-PCR kits, AccuPower® COVID-19 Multiplex Real-Time RT-PCR Kit (NCVM) specifically designed for use with the ExiStation™48 system (comprised of ExiPrep™48 Dx and Exicycler™96 by BIONEER, Korea) for sample RNA extraction and PCR detection, and AccuPower® SARS-CoV-2 Multiplex Real-Time RT-PCR Kit (SCVM) designed to be compatible with manufacturers' on-market PCR instruments. The limit of detection (LoD) of NCVM was 120 copies/mL and the LoD of the SCVM was 2 copies/µL for both the Pan-sarbecovirus gene and the SARS-CoV-2 gene. The AccuPower® kits demonstrated high precision with no cross reactivity to other respiratory-related microorganisms. The clinical performance of AccuPower® kits was evaluated using the following clinical samples: sputum and nasopharyngeal/oropharyngeal swab (NPS/OPS) samples. Overall agreement of the AccuPower® kits with a Food and Drug Administration (FDA) approved emergency use authorized commercial kit (STANDARD™ M nCoV Real-Time Detection kit, SD BIOSENSOR, Korea) was above 95% (Cohen's kappa coefficient ≥ 0.95), with a sensitivity of over 95%. The NPS/OPS specimen pooling experiment was conducted to verify the usability of AccuPower® kits on pooled samples and the results showed greater than 90% agreement with individual NPS/OPS samples. The clinical performance of AccuPower® kits with saliva samples was also compared with NPS/OPS samples and demonstrated over 95% agreement (Cohen's kappa coefficient > 0.95). This study shows the BIONEER NCVM and SCVM assays are comparable with the current standard confirmation assay and are suitable for effective clinical management and control of SARS-CoV-2.

Macrophage targeted theranostic strategy for accurate detection and rapid stabilization of the inflamed high-risk plaque.

Rationale: Inflammation plays a pivotal role in the pathogenesis of the acute coronary syndrome. Detecting plaques with high inflammatory activity and specifically treating those lesions can be crucial to prevent life-threatening cardiovascular events. Methods: Here, we developed a macrophage mannose receptor (MMR)-targeted theranostic nanodrug (mannose-polyethylene glycol-glycol chitosan-deoxycholic acid-cyanine 7-lobeglitazone; MMR-Lobe-Cy) designed to identify inflammatory activity as well as to deliver peroxisome proliferator-activated gamma (PPARγ) agonist, lobeglitazone, specifically to high-risk plaques based on the high mannose receptor specificity. The MMR-Lobe-Cy was intravenously injected into balloon-injured atheromatous rabbits and serial in vivo optical coherence tomography (OCT)-near-infrared fluorescence (NIRF) structural-molecular imaging was performed. Results: One week after MMR-Lobe-Cy administration, the inflammatory NIRF signals in the plaques notably decreased compared to the baseline whereas the signals in saline controls even increased over time. In accordance with in vivo imaging findings, ex vivo NIRF signals on fluorescence reflectance imaging (FRI) and plaque inflammation by immunostainings significantly decreased compared to oral lobeglitazone group or saline controls. The anti-inflammatory effect of MMR-Lobe-Cy was mediated by inhibition of TLR4/NF-κB pathway. Furthermore, acute resolution of inflammation altered the inflamed plaque into a stable phenotype with less macrophages and collagen-rich matrix. Conclusion: Macrophage targeted PPARγ activator labeled with NIRF rapidly stabilized the inflamed plaques in coronary sized artery, which could be quantitatively assessed using intravascular OCT-NIRF imaging. This novel theranostic approach provides a promising theranostic strategy for high-risk coronary plaques.

A Worker-Centered Personal Health Record App for Workplace Health Promotion Using National Health Care Data Sets: Design and Development Study.

BACKGROUND: Personal health record (PHR) technology can be used to support workplace health promotion, and prevent social and economic losses related to workers' health management. PHR services can not only ensure interoperability, security, privacy, and data quality, but also consider the user's perspective in their design. OBJECTIVE: Using Fast Healthcare Interoperability Resources (FHIR) and national health care data sets, this study aimed to design and develop an app for providing worker-centered, interconnected PHR services. METHODS: This study considered the user's perspective, using the human-centered design (HCD) methodology, to develop a PHR app suitable for occupational health. We developed a prototype after analyzing quantitative and qualitative data collected from workers and a health care professional group, after which we performed a usability evaluation. We structured workers' PHR items based on the analyzed data, and ensured structural and semantic interoperability using FHIR, Systematized Nomenclature of Medicine-Clinical Terms (SNOMED-CT), and Logical Observation Identifiers Names and Codes (LOINC). This study integrated workers' health information scattered across different Korean institutions through an interface method, and workers' PHRs were managed through a cloud server, using Azure API for FHIR. RESULTS: In total, 562 workers from industrial parks participated in the quantitative study. The preferred data items for PHR were medication, number of steps walked, diet, blood pressure, weight, and blood glucose. The preferred features were ability to access medical checkup results, health information content provision, consultation record inquiry, and teleconsultation. The worker-centered PHR app collected data on, among others, life logs, vital signs, and medical checkup results; offered health care services such as reservation and teleconsultation; and provided occupational safety and health information through material safety data sheet search and health questionnaires. The app reflected improvements in user convenience and app usability proposed by 19 participants (7 health care professionals and 12 end users) in the usability evaluation. The After-Scenario Questionnaire (ASQ) was evaluated with a mean score of 5.90 (SD 0.34) out of 7, and the System Usability Scale (SUS) was evaluated a mean score of 88.7 (SD 4.83) out of 100. CONCLUSIONS: The worker-centered PHR app integrates workers' health information from different institutions and provides a variety of health care services from linked institutions through workers' shared PHR. This app is expected to increase workers' autonomy over their health information and support medical personnel's decision making regarding workers' health in the workplace. Particularly, the app will provide solutions for current major PHR challenges, and its design, which considers the user's perspective, satisfies the prerequisites for its utilization in occupational health.

Development and Operation of a Video Teleconsultation System Using Integrated Medical Equipment Gateway: a National Project for Workers in Underserved Areas.

Worker health centers and health zones provide occupational healthcare services to workers in underserved areas of industrial health. Health zones cannot counsel workers on occupational disease prevention; worker health center personnel have to provide such services through in-person visits. Video teleconsultation can increase the accessibility of high-quality services to workers who visit health zones and improve professional personnel's efficiency. This study aimed to develop a system and an infrastructure that could facilitate video teleconsultation services between worker health centers and health zones, and analyze the services' operation status. A video teleconsultation process based on the role of local and remote institutions was designed. Based on the designed services, a web system supporting teleconsultation and an integrated gateway guaranteeing the interface with medical equipment in the web environment was developed. After analyzing the working environment, an infrastructure consisting of networks, video equipment, medical equipment, and servers necessary for teleconsultation was designed. Statistical results from the developed system and a satisfaction survey conducted by the Korea Occupational Safety and Health Agency were used to analyze the video teleconsultation services' operation status. A system, gateway, and hardware infrastructure within 21 worker health centers and 21 health zones has been operating this service since January 1, 2018. Over two years, the total number of teleconsultation service users was 4979, and the total number of questionnaire respondents was 1270. The total number of service activities was 6388 and total satisfaction was rated as 4.58 (± 0.59) out of 5. In this study, video teleconsultation services were evaluated as being very satisfactory. In particular, service accessibility and local medical personnel service were rated highly, demonstrating that the developed system and infrastructure were well designed according to the goals of the project.

Factors Influencing Acceptance of Personal Health Record Apps for Workplace Health Promotion: Cross-Sectional Questionnaire Study.

BACKGROUND: Health care technologies can help improve workers' health and productivity by supporting workplace health promotion. A personal health record app is used to manage medical data such as results from medical checkups, which facilitates decision making for medical personnel. However, an analysis of users' technology acceptance is required to provide appropriate services based on personal health record apps. OBJECTIVE: The purpose of this study was to analyze the factors influencing the behavioral intention of health experts and workers to use an app in workers' health centers and to examine differences in their perception of the main variables. METHODS: The study involved health experts and workers who visited 21 workers' health centers in Korea to verify a research model in which perceived risk was added to the unified theory of acceptance and use of technology, a representative theory of information technology acceptance. After receiving ethical approval from the Korea National Institute for Bioethics Policy, 1050 questionnaires were distributed over 7 weeks with cooperation of the Korea Occupational Safety and Health Agency. A multiple linear regression analysis and multigroup path analysis were performed to verify the hypotheses, and independent samples t tests were performed to analyze differences between workers' and health experts' perception of the main variables. RESULTS: The analysis included data from 866 respondents (687 workers and 179 health experts). Effort expectancy (beta=.08, P=.03), social influence (beta=.43, P<.001), performance expectancy (beta=.07, P=.008), and facilitating conditions (beta=.13, P<.001) exerted significant positive effects on behavioral intention, whereas perceived risk (beta=-.29, P<.001) exerted a significant negative effect on behavioral intention. Performance expectancy had a significant effect on path differences depending on gender (critical ratio=-3.38) and age (critical ratio=1.97). Workers' mean scores for the main variables were higher relative to those of health experts for all remaining variables except perceived risk, and significant differences were observed for all remaining variables except facilitating condition. CONCLUSIONS: Social influence exerted the strongest effect on behavioral intention to use the personal health record app. Consequently, it is necessary to coordinate health promotion activities in the workplace as well as the operational direction of community institutions such as in workers' health centers to allow workers to manage their own health via continuous use of the app. In addition, the app should be developed based on a requirement analysis of the balance between both interest groups in consideration of differences in perspective between consumers and service providers.

Color reproduction pipeline for an RGBW color filter array sensor.

Many types of RGBW color filter array (CFA) have been proposed for various purposes. Most studies utilize white pixel intensity for improving the signal-to-noise ratio of the image and demosaicing the image, but we note that the white pixel intensity can also be utilized to improve color reproduction. In this paper, we propose a color reproduction pipeline for RGBW CFA sensors based on a fast, accurate, and hardware-friendly gray pixel detection using white pixel intensity. The proposed color reproduction pipeline was tested on a dataset captured from an OPA sensor which has RGBW CFA. Experimental results show that the proposed pipeline estimates the illumination more accurately and preserves the achromatic color better than conventional methods which do not use white pixel intensity.

Single cardiac cycle three-dimensional intracoronary optical coherence tomography.

While high-speed intracoronary optical coherence tomography (OCT) provides three-dimensional (3D) visualization of coronary arteries in vivo, imaging speeds remain insufficient to avoid motion artifacts induced by heartbeat, limiting the clinical utility of OCT. In this paper, we demonstrate development of a high-speed intracoronary OCT system (frame rate: 500 frames/s, pullback speed: 100 mm/s) along with prospective electrocardiogram (ECG) triggering technology, which enabled volumetric imaging of long coronary segments within a single cardiac cycle (70 mm pullback in 0.7 s) with minimal cardiac motion artifact. This technology permitted detailed visualization of 3D architecture of the coronary arterial wall of a swine in vivo and fine structure of the implanted stent.

Development of an Integrated Biospecimen Database among the Regional Biobanks in Korea.

OBJECTIVES: This study developed an integrated database for 15 regional biobanks that provides large quantities of high-quality bio-data to researchers to be used for the prevention of disease, for the development of personalized medicines, and in genetics studies. METHODS: We collected raw data, managed independently by 15 regional biobanks, for database modeling and analyzed and defined the metadata of the items. We also built a three-step (high, middle, and low) classification system for classifying the item concepts based on the metadata. To generate clear meanings of the items, clinical items were defined using the Systematized Nomenclature of Medicine Clinical Terms, and specimen items were defined using the Logical Observation Identifiers Names and Codes. To optimize database performance, we set up a multi-column index based on the classification system and the international standard code. RESULTS: As a result of subdividing 7,197,252 raw data items collected, we refined the metadata into 1,796 clinical items and 1,792 specimen items. The classification system consists of 15 high, 163 middle, and 3,588 low class items. International standard codes were linked to 69.9% of the clinical items and 71.7% of the specimen items. The database consists of 18 tables based on a table from MySQL Server 5.6. As a result of the performance evaluation, the multi-column index shortened query time by as much as nine times. CONCLUSIONS: The database developed was based on an international standard terminology system, providing an infrastructure that can integrate the 7,197,252 raw data items managed by the 15 regional biobanks. In particular, it resolved the inevitable interoperability issues in the exchange of information among the biobanks, and provided a solution to the synonym problem, which arises when the same concept is expressed in a variety of ways.

Development of a Multi-Agent m-Health Application Based on Various Protocols for Chronic Disease Self-Management.

The purpose of this study was to develop and evaluate a mobile health application (Self-Management mobile Personal Health Record: "SmPHR") to ensure the interoperability of various personal health devices (PHDs) and electronic medical record systems (EMRs) for continuous self-management of chronic disease patients. The SmPHR was developed for Android 4.0.3, and implemented according to the optimized standard protocol for each interface of healthcare services adopted by the Continua Health Alliance (CHA). That is, the Personal Area Network (PAN) interface between the application and PHD implements ISO/IEEE 11073-20,601, 10,404, 10,407, 10,415, 10,417, and Bluetooth Health Device Profile (HDP), and EMRs with a wide area network (WAN) interface implement HL7 V2.6; the Health Record Network (HRN) interface implements Continuity of Care Document (CCD) and Continuity of Care Record (CCR). Also, for SmPHR, we evaluated the transmission error rate between the interface using four PHDs and personal health record systems (PHRs) from previous research, with 611 users and elderly people after receiving institutional review board (IRB) approval. In the evaluation, the PAN interface showed 15 (2.4 %) errors, and the WAN and HRN interface showed 13 (2.1 %) errors in a total of 611 transmission attempts. Also, we received opinions regarding SmPHR from 15 healthcare professionals who took part in the clinical trial. Thus, SmPHR can be provided as an interconnected PHR mobile health service to patients, allowing 'plug and play' of PHDs and EMRs through various standard protocols.

Development of Cell Phone Application for Blood Glucose Self-Monitoring Based on ISO/IEEE 11073 and HL7 CCD.

OBJECTIVES: The objectives of this research were to develop and evaluate a cell phone application based on the standard protocol for personal health devices and the standard information model for personal health records to support effective blood glucose management and standardized service for patients with diabetes. METHODS: An application was developed for Android 4.0.3. In addition, an IEEE 11073 Manager, Medical Device Encoding Rule, and Bluetooth Health Device Profile Connector were developed for standardized health communication with a glucometer, and a Continuity of Care Document (CCD) Composer and CCD Parser were developed for CCD document exchange. The developed application was evaluated by five healthcare professionals and 87 users through a questionnaire comprising the following variables: usage intention, effort expectancy, social influence, facilitating condition, perceived risk, and voluntariness. RESULTS: As a result of the evaluation of usability, it was confirmed that the developed application is useful for blood glucose self-monitoring by diabetic patients. In particular, the healthcare professionals stated their own views that the application is useful to observe the trends in blood glucose change through the automatic function which records a blood glucose level measured using Bluetooth function, and the function which checks accumulated records of blood glucose levels. Also, a result of the evaluation of usage intention was 3.52 ± 0.42 out of 5 points. CONCLUSIONS: The application developed by our research team was confirmed by the verification of healthcare professionals that accurate feedback can be provided to healthcare professionals during the management of diabetic patients or education for glucose management.

One-year clinical outcomes in invasive treatment strategies for acute ST-elevation myocardial infarction complicated by cardiogenic shock in eld-erly patients / 老年心脏病学杂志（英文版）

Objective To investigate the clinical outcomes of an invasive strategy for elderly (aged≥75 years) patients with acute ST-segment elevation myocardial infarction (STEMI) complicated by cardiogenic shock (CS). Methods Data on 366 of 409 elderly CS patients from a total of 6,132 acute STEMI cases enrolled in the Korea Acute Myocardial Infarction Registry between January 2008 and June 2011, were collected and analyzed. In-hospital deaths and the 1-month and 1-year survival rates free from major adverse cardiac events (MACE;defined as all cause death, myocardial infarction, and target vessel revascularization) were reported for the patients who had undergone invasive (n=310) and conservative (n=56) treatment strategies. Results The baseline clinical characteristics were not significantly different between the two groups. There were fewer in-hospital deaths in the invasive treatment strategy group (23.5%vs. 46.4%, P＜0.001). In addition, the 1-year MACE-free survival rate after invasive treatment was significantly lower compared with the conservative treatment (51%vs. 66%, P=0.001). Conclusions In elderly patients with acute STEMI complicated by CS, the outcomes of invasive strategy are similar to those in younger patients at the 1-year follow-up.