The SpACE-CCM: A facile and versatile cell culture medium-based biosensor for detection of SARS-CoV-2 spike-ACE2 interaction.

The COVID-19 pandemic is an ongoing global public health threat. COVID-19 is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, and binding of the SARS-CoV-2 spike to its receptor, angiotensin-converting enzyme 2 (ACE2), on host cells is critical for viral infection. Here, we developed a luminescent biosensor that readily detects interactions of the spike receptor-binding domain (RBD) and ACE2 in cell culture medium ('SpACE-CCM'), which was based on bimolecular complementation of the split nanoluciferase-fused spike RBD and ectodomain of ACE2 and further engineered to be efficiently secreted from cells by adding a heterologous secretory signal peptide (SSP). Screening of various SSPs identified 'interferon-α+alanine-aspartate' as the SSP that induced the highest activity. The SpACE-CCM biosensor was validated by observing a marked reduction of the activity caused by interaction-defective mutations or in the presence of neutralizing antibodies, recombinant decoy proteins, or peptides. Importantly, the SpACE-CCM biosensor responded well in assay-validating conditions compared with conventional cell lysate-based NanoLuc Binary Technology, indicating its advantage. We further demonstrated the biosensor's versatility by quantitatively detecting neutralizing activity in blood samples from COVID-19 patients and vaccinated individuals, discovering a small molecule interfering with the spike RBD-ACE2 interaction through high-throughput screening, and assessing the cross-reactivity of neutralizing antibodies against SARS-CoV-2 variants. Because the SpACE-CCM is a facile and rapid one-step reaction biosensor that aptly recapitulates the native spike-ACE2 interaction, it would be advantageous in many experimental and clinical applications associated with this interaction.

Laboratory and clinical teaching experience of nursing professors in the COVID-19 pandemic era: Now and the future.

Nursing professors must constantly interact with students, maintain a high level of professional performance, and meet targets and deadlines, even during a pandemic. Considering the changing educational environment, it is essential to identify contemporary limitations and problems to provide feedback for improvement. This study aimed to explore the laboratory and clinical teaching experiences of nursing professors during the COVID-19 pandemic. Focus group interviews were conducted with professors from the nursing departments of universities in Korea. In total, 19 professors who had laboratory and clinical experience participated in this study. The collected data were analyzed using thematic analysis. The analysis identified four themes. The themes included feeling helpless in the infection management system, uncertainty about the effectiveness of alternative practice training, acceptance of changes, and preparation for future practice training. As the necessity and possibility of non-face-to-face education have been confirmed by the pandemic, it is expected that classes using technology will be actively developed in nursing practice education. The roles and attitudes of teachers and educational institutions also need to change. Nursing professors should reflect upon and evaluate challenges to prepare for post-pandemic practical education.

Instructional design and educational satisfaction for virtual environment simulation in undergraduate nursing education: the mediating effect of learning immersion.

BACKGROUND: Schools were closed after the onset of COVID-19, with non-face-to-face practices or distance education in nursing education replacing video learning or simulation classes in nursing education clinical practicum. This led to an increase in interest in virtual environment simulation education. While technology-based teaching methods might feel new and intriguing to learners, it is necessary to evaluate learner satisfaction with such an educational method beyond its novelty value. Therefore, this study examined the mediating effect of learning immersion on the relationships between instructional design and educational satisfaction, for virtual environment simulation. METHODS: A descriptive cross-sectional research design was used. The study sample included students in the third or fourth year of the nursing curriculum in South Korea. The participants were 164 nursing students, who had an experience with virtual environment simulation practices during the past year, prior to September 2021. Data were collected using an online questionnaire. The questionnaire addressed the characteristics of nursing students, instructional design, learning immersion, and educational satisfaction. The collected data were analyzed using path analysis. RESULTS: The indirect effect of the path between instructional design and educational satisfaction, mediated through learning immersion in virtual environment simulation was found to be significant. Furthermore, the direct path was also statistically significant. CONCLUSION: Educational content, based on virtual environment simulation, should be implemented based on instructional design. It is necessary to recognize the importance of instructional design that can promote learning immersion in virtual environment simulation, as well as to prepare consistent standards for such design.

Risk factors influencing COVID-19 mortality rate in OECD countries: A cross-sectional study.

SUMMARY: The coronavirus disease (COVID-19) has spread globally; however, the COVID-19 mortality rate varies largely across countries. The purpose of this study was to investigate the factors affecting mortality and increase in mortality rate by time trends in 30 member countries of the Organization for Economic Co-operation and Development (OECD). These countries have different national health and medical characteristics in terms of health care use, health equipment, health resource, health risk, and health status at different time points. The results revealed that the lower 25% of countries had an increase in the mortality rate of 27.21% which was higher than the upper 25% of countries' increase in the mortality rate of 20.51%. Therefore, the affected countries should strengthen their medical infrastructure to prepare for such large-scale outbreaks in the future. It is imperative to reduce the health inequality between population groups and achieve health equity, regardless of the income gap, rather than vaccination of specific countries. This will require the management of non-communicable diseases, a solid health insurance system, a stable supply of medical supplies, and strengthening the competency of health care workers.

Validation of GeneFinder COVID-19 Ag Plus Rapid Test and Its Potential Utility to Slowing Infection Waves: A Single-Center Laboratory Evaluation Study.

Diagnostic laboratory tools are essential to keep everyone safe and track newly emerging variants; on the other hand, "filter" screening tests recognizing positivity are valuable tools to avoid hectic laboratory work that, besides COVID-19, are also part of the routine. Therefore, complementary assays, such as rapid antigen tests (RATs), are essential in controlling and monitoring virus spread within the community, especially in the asymptomatic population. A subset of nasopharyngeal swab specimens resulted in SARS-CoV-2 positive and investigated for genomic characterization were used for RAT validation. RATs were performed immediately after sampling, following the manufacturer's instructions (reading at 15 min). RT-PCRs were carried out within 24 h of specimens' collection. Out of 603 patients, 145 (24.05%) tested positive by RT-PCR and RAT and 451 (74.79%) tested negative by both methods; discordant results (RT-PCR+/RAT- or RT-PCR-/RAT+) were obtained in 7 patients (1.16%). RATs' overall specificity and sensitivity were 96.03% (95%CI: 91.55-98.53%) and 99.78% (95%CI: 98.77-99.99%), respectively, taking RT-PCR as the reference. Overall, RAT negative predictive value was 98.69% (95%CI 97.17-99.40%). The GeneFinder COVID-19 Ag Plus Rapid Test performed well as a screening test for early diagnosis of COVID-19, especially in asymptomatic subjects. The data suggested that patients with RT-PCR-proven COVID-19 testing negative by RAT are unlikely to be infectious. GeneFinder COVID-19 Ag Plus Rapid Test also works on variants of concern (VOC) delta and omicron BA.1 and BA.2.

Encountering COVID-19 as Endocrinologists.

The world is entering an era of disaster and chaos due to coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus 2. Since its first emergence in December 2019 in Wuhan, China, COVID-19 has swept through Asia and propagated throughout the world to Europe and North America. As of April 13, 1,773,084 people were infected and 111,652 people had died from COVID-19 globally, and new record levels of infection are being reported every day. Based on the data that have been amassed so far, the primary risk factors for a severe disease course or even mortality from COVID-19 are underlying diseases such as diabetes and hypertension. As the global prevalence of diabetes continues to increase, patients with endocrine diseases such as diabetes mellitus and those who are on long-term corticosteroid therapy due to adrenal insufficiency or hypopituitarism are at risk for a poor prognosis of COVID-19. As endocrinologists, we would like to briefly review the current knowledge about the relationship between COVID-19 and endocrine diseases and to discuss what we can do for the safety and health of our patients with endocrine diseases in this globally threatening situation.