Objective: Patients with severe symptomatic aortic stenosis are assessed for coronary artery disease (CAD) prior to transcatheter aortic valve implantation (TAVI) with treatment implications. Invasive coronary angiography (ICA) is the recommended modality but is associated with peri-procedural complications. Integrating machine learning (ML)-based computed tomography-derived fractional flow reserve (CT-FFR) into existing TAVI-planning CT protocol may aid exclusion of significant CAD and thus avoiding ICA in selected patients. Materials and Methods: A single-center, retrospective study was conducted, 41 TAVI candidates with both TAVI-planning CT and ICA performed were analyzed. CT datasets were evaluated by a ML-based CT-FFR software. Beta-blocker and nitroglycerin were not administered in these patients. The primary outcome was to identify significant CAD. The diagnostic performance of CT-FFR was compared against ICA. Results: On per-patient level, the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and diagnostic accuracy were 89%, 94%, 80%, 97% and 93%, respectively. On per-vessel level, the sensitivity, specificity, PPV, NPV and diagnostic accuracy were 75%, 94%, 67%, 96% and 92%, respectively. The area under the receiver operative characteristics curve per individual coronary vessels yielded overall 0.90 (95% confidence interval 85%–95%). ICA may be avoided in up to 80% of patients if CT-FFR results were negative. Conclusion ML-based CT-FFR can provide accurate screening capabilities for significant CAD thus avoiding ICA. Its integration to existing TAVI-planning CT is feasible with the potential of improving the safety and efficiency of pre-TAVI CAD assessment.

Background: We evaluated changes in glycemic status, over 1 year, of coronavirus disease 2019 (COVID-19) survivors with dysglycemia in acute COVID-19. Methods: COVID-19 survivors who had dysglycemia (defined by glycosylated hemoglobin [HbA1c] 5.7% to 6.4% or random glucose ≥10.0 mmol/L) in acute COVID-19 were recruited from a major COVID-19 treatment center from September to October 2020. Matched non-COVID controls were recruited from community. The 75-g oral glucose tolerance test (OGTT) were performed at baseline (6 weeks after acute COVID-19) and 1 year after acute COVID-19, with HbA1c, insulin and C-peptide measurements. Progression in glycemic status was defined by progression from normoglycemia to prediabetes/diabetes, or prediabetes to diabetes. Results: Fifty-two COVID-19 survivors were recruited. Compared with non-COVID controls, they had higher C-peptide (P< 0.001) and trend towards higher homeostasis model assessment of insulin resistance (P=0.065). Forty-three COVID-19 survivors attended 1-year reassessment. HbA1c increased from 5.5%±0.3% to 5.7%±0.2% (P<0.001), with increases in glucose on OGTT at fasting (P=0.089), 30-minute (P=0.126), 1-hour (P=0.014), and 2-hour (P=0.165). At baseline, 19 subjects had normoglycemia, 23 had prediabetes, and one had diabetes. Over 1 year, 10 subjects (23.8%; of 42 non-diabetes subjects at baseline) had progression in glycemic status. C-peptide levels remained unchanged (P=0.835). Matsuda index decreased (P=0.007) and there was a trend of body mass index increase from 24.4±2.7 kg/m2 to 25.6±5.2 (P=0.083). Subjects with progression in glycemic status had more severe COVID-19 illness than non-progressors (P=0.030). Reassessment was not performed in the control group. Conclusion Subjects who had dysglycemia in acute COVID-19 were characterized by insulin resistance. Over 1 year, a quarter had progression in glycemic status, especially those with more severe COVID-19. Importantly, there was no significant deterioration in insulin secretory capacity.

Background: Insulin-treated patients with long duration of type 2 diabetes mellitus (T2DM) are at increased risk of ketoacidosis related to sodium-glucose co-transporter 2 inhibitor (SGLT2i). The extent of circulating ketone elevation in these patients remains unknown. We conducted this study to compare the serum ketone response between dapagliflozin, an SGLT2i, and sitagliptin, a dipeptidyl peptidase-4 inhibitor, among insulin-treated T2DM patients. Methods: This was a randomized, open-label, active comparator-controlled study involving 60 insulin-treated T2DM patients. Participants were randomized 1:1 for 24-week of dapagliflozin 10 mg daily or sitagliptin 100 mg daily. Serum β-hydroxybutyrate (BHB) levels were measured at baseline, 12 and 24 weeks after intervention. Comprehensive cardiometabolic assessments were performed with measurements of high-density lipoprotein cholesterol (HDL-C) cholesterol efflux capacity (CEC), vibration-controlled transient elastography and echocardiography. Results: Among these 60 insulin-treated participants (mean age 58.8 years, diabetes duration 18.2 years, glycosylated hemoglobin 8.87%), as compared with sitagliptin, serum BHB levels increased significantly after 24 weeks of dapagliflozin (P=0.045), with a median of 27% increase from baseline. Change in serum BHB levels correlated significantly with change in free fatty acid levels. Despite similar glucose lowering, dapagliflozin led to significant improvements in body weight (P=0.006), waist circumference (P=0.028), HDL-C (P=0.041), CEC (P=0.045), controlled attenuation parameter (P=0.007), and liver stiffness (P=0.022). Average E/e’, an echocardiographic index of left ventricular diastolic dysfunction, was also significantly lower at 24 weeks in participants treated with dapagliflozin (P=0.037). Conclusion Among insulin-treated T2DM patients with long diabetes duration, compared to sitagliptin, dapagliflozin modestly increased ketone levels and was associated with cardiometabolic benefits.

Introduction: Professional commitment encompasses affirmation of profession goals and values and a strong sense of profession loyalty. Nurses’ professional commitment is important as nurses represent the majority of healthcare professionals. Nurses play an essential role in maintaining patient safety and offering high care quality. This study aimed to examine the relationship of nurses’ professional commitment with patient safety and patient satisfaction about care quality in the Malaysian healthcare context. Methods: A cross-sectional design with a questionnaire was adopted using pairs of nurse and in-patient from a Malaysian university teaching hospital. The questionnaire measuring nurses’ professional commitment from Meyer and Allen’s organizational commitment scale was used. The nurses’ questionnaire also incorporated the Teng, Chang and Hsu’s patient safety scale of six adverse actions to assess the patient safety level among nurses. The questionnaire for patients utilized the Service Quality Scale by Teng, Shyu and Chang to measure the patient satisfaction about care quality. Using the online survey channel to administer the questionnaires, 170 questionnaires were filled by nurses and this was matched by 170 questionnaires being completed by patients. Pearson correlation coefficient was used for the analysis. Results: The results show that nurses’ professional commitment has a positive relationship with the patient satisfaction (r= 0.225, p= 0.003) while no significant relationship was found between nurses’ professional commitment and patient safety. Conclusion: Efforts could be made to incorporate elements of professional commitment into nursing quality training programs. Managing patient safety and service quality across ward specialties may require tailoring of service provision aspects in line with different levels of patient care needs and complexity.

INTRODUCTION: Chest radiographs (CXRs) are widely used for the screening and management of COVID-19. This article describes the radiographic features of COVID-19 based on an initial national cohort of patients. METHODS: This is a retrospective review of swab-positive patients with COVID-19 who were admitted to four different hospitals in Singapore between 22 January and 9 March 2020. Initial and follow-up CXRs were reviewed by three experienced radiologists to identify the predominant pattern and distribution of lung parenchymal abnormalities. RESULTS: In total, 347 CXRs of 96 patients were reviewed. Initial CXRs were abnormal in 41 (42.7%) out of 96 patients. The mean time from onset of symptoms to CXR abnormality was 5.3 ± 4.7 days. The predominant pattern of lung abnormality was ground-glass opacity on initial CXRs (51.2%) and consolidation on follow-up CXRs (51.0%). Multifocal bilateral abnormalities in mixed central and peripheral distribution were observed in 63.4% and 59.2% of abnormal initial and follow-up CXRs, respectively. The lower zones were involved in 90.2% of initial CXRs and 93.9% of follow-up CXRs. CONCLUSION In a cohort of swab-positive patients, including those identified from contact tracing, we found a lower incidence of CXR abnormalities than was previously reported. The most common pattern was ground-glass opacity or consolidation, but mixed central and peripheral involvement was more common than peripheral involvement alone.
COVID-19 ; Humans ; Lung/diagnostic imaging* ; Radiography, Thoracic ; Retrospective Studies ; SARS-CoV-2 ; Singapore

Background: Fatigue is pervasive, under-reported, and potentially deadly where flight operations are concerned. The aviation industry appears to lack a standardized, practical, and easily replicable protocol for fatigue risk assessment which can be consistently applied across operators.AimOur paper sought to present a framework, supported by real-world data with subjective and objective parameters, to monitor aircrew fatigue and performance, and to determine the safe crew configuration for commercial airline operations. Methods: Our protocol identified risk factors for fatigue-induced performance degradation as triggers for fatigue risk and performance assessment. Using both subjective and objective measurements of sleep, fatigue, and performance in the form of instruments such as the Karolinska Sleepiness Scale, Samn-Perelli Crew Status Check, Psychomotor Vigilance Task, sleep logs, and a wearable actigraph for sleep log correlation and sleep duration and quality charting, a workflow flagging fatigue-prone flight operations for risk mitigation was developed and trialed. Results: In an operational study aimed at occupational assessment of fatigue and performance in airline pilots on a three-men crew versus a four-men crew for a long-haul flight, we affirmed the technical feasibility of our proposed framework and approach, the validity of the battery of assessment instruments, and the meaningful interpretation of fatigue and work performance indicators to enable the formulation of safe work recommendations. Conclusion A standardized occupational assessment protocol like ours is useful to achieve consistency and objectivity in the occupational assessment of fatigue and work performance.

The Japanese encephalitis virus (JEV), a leading cause of encephalitis, exists as quasispecies in clinical isolates. Using a limiting dilution method combined with immunohistochemistry to detect viral antigens, 10 biological clones were isolated and purified from a clinical JEV isolate (CNS138/9) derived from an autopsy brain. These biological clones were tested for neurovirulence in SK-N-MC and NIE-115 neuronal cells, and a 2-week-old, footpad-infected, JE mouse model. Nine clones were found to be neurovirulent; one clone neuroattenuated. Although further studies are needed to determine genotypic differences, if any, in these clones, the limiting dilution purification and neurovirulence testing methods described herein should be useful for phenotypic studies of quasispecies of neurotropic viruses in general, and JEV and other flaviviruses in particular.

In this paper, we aim to provide professional guidance to clinicians who are managing patients with chronic liver disease during the current coronavirus disease 2019 (COVID-19) pandemic in Singapore. We reviewed and summarised the available relevant published data on liver disease in COVID-19 and the advisory statements that were issued by major professional bodies, such as the American Association for the Study of Liver Diseases and European Association for the Study of the Liver, contextualising the recommendations to our local situation.
COVID-19/epidemiology* ; Carcinoma, Hepatocellular/therapy* ; Chronic Disease ; Hepatitis B, Chronic/therapy* ; Hepatitis C, Chronic/therapy* ; Humans ; Liver Cirrhosis/therapy* ; Liver Diseases/therapy* ; Liver Neoplasms/therapy* ; Liver Transplantation ; Singapore/epidemiology*

Betacoronavirus ; Communicable Disease Control ; organization & administration ; Coronavirus Infections ; epidemiology ; prevention & control ; transmission ; Disaster Planning ; organization & administration ; Humans ; Nuclear Medicine ; organization & administration ; Pandemics ; prevention & control ; Pneumonia, Viral ; epidemiology ; prevention & control ; transmission ; Singapore

In ASEAN, the number of confirmed COVID-19 cases is reported with little information on the number of screening tests performed or the criteria for who is tested. We highlight the need for enhanced surveillance and reporting of the number of people screened and screening criteria when testing capacity is limited.