TRIM21 promotes ubiquitination of SARS-CoV-2 nucleocapsid protein to regulate innate immunity.

The innate immune response is the first line of host defense against viral infections, but its role in immunity against SARS-CoV-2 remains unclear. By using immunoprecipitation coupled with mass spectroscopy, we observed that the E3 ubiquitin ligase TRIM21 interacted with the SARS-CoV-2 nucleocapsid (N) protein and ubiquitinated it at Lys375 . Upon determining the topology of the TRIM21-mediated polyubiquitination chain on N protein, we then found that polyubiquitination led to tagging of the N protein for degradation by the host cell proteasome. Furthermore, TRIM21 also ubiquitinated the N proteins of SARS-CoV-2 variants of concern, including Alpha, Beta, Gamma, Delta, and Omicron together with SARS-CoV and MERS-CoV variants. Herein, we propose that ubiquitylation and degradation of the SARS-CoV-2 N protein inhibited SARS-CoV-2 viral particle assembly, by which it probably involved in preventing cytokine storm. Eventually, our study has fully revealed the association between the host innate immune system and SARS-CoV-2 N protein, which may aid in developing novel SARS-CoV-2 treatment strategies.

Immunomolecular assay based on selective virion capture by spike antibody and viral nucleic acid amplification for detecting intact SARS-CoV-2 particles.

BACKGROUND: Effective therapeutics and vaccines for coronavirus disease 2019 (COVID-19) are currently lacking because of the mutation and immune escape of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Based on the propagation characteristics of SARS-CoV-2, rapid and accurate detection of complete virions from clinical samples and the environment is critical for assessing infection risk and containing further COVID-19 outbreaks. However, currently applicable methods cannot achieve large-scale clinical application due to factors such as the high viral load, cumbersome virus isolation steps, demanding environmental conditions, and long experimental periods. In this study, we developed an immuno molecular detection method combining capture of the viral spike glycoprotein with monoclonal antibodies and nucleic acid amplification via quantitative reverse transcription PCR to rapidly and accurately detect complete virions. RESULTS: After constructing a novel pseudovirus, screening for specific antibodies, and optimizing the detection parameters, the assay achieved a limit of detection of 9 × 102 transduction units/mL of viral titer with high confidence (~ 95%) and excellent stability against human serum and common virus/pseudovirus. The coefficients of variation were 1.0 ~ 2.0% for intra-assay and inter-assay analyses, respectively. Compared with reverse transcription-PCR, the immunomolecular method more accurately quantified complete virions. SARS-CoV-2/pseudovirus was more stable on plastic and paper compared with aluminum and copper in the detection of SARS-CoV-2 pseudovirus under different conditions. Complete virions were detected up to 96 h after they were applied to these surfaces (except for copper), although the titer of the virions was greatly reduced. CONCLUSION: Convenient, inexpensive, and accurate complete virus detection can be applied to many fields, including monitoring the infectivity of convalescent and post-discharge patients and assessing high-risk environments (isolation rooms, operating rooms, patient living environments, and cold chain logistics). This method can also be used to detect intact virions, including Hepatitis B and C viruses, human immunodeficiency virus, influenza, and the partial pulmonary virus, which may further improve the accuracy of diagnoses and facilitate individualized and precise treatments.

Prevalence and correlates of mental disorders among Chinese overseas students during the COVID-19: A multi-regional cross-sectional analysis.

BACKGROUND: The global impact of the COVID-19 pandemic extends beyond physical health, significantly affecting mental health. Chinese overseas students are particularly susceptible to the adverse psychological effects of the pandemic. Understanding the prevalence and correlates of mental disorders in this population is essential for developing targeted interventions and support systems. METHODS: Employing a snowball sampling technique, this study recruited Chinese overseas students from diverse regions. The 50-item Self-evaluation Table was utilized to assess the presence of mental disorders. Descriptive statistics, including percentages, 95% confidence intervals, means, and standard deviations, characterized the survey population. The chi-square test identified disparities among categorical variables, while logistic regression explored risk factors for mental disorders among Chinese overseas students. RESULTS: Out of the total sample size of 10,864 Chinese overseas students, a staggering 7,090 (65.4%) met the diagnostic criteria for mental disorders. Furthermore, the degree of mental disorder varied significantly across different regions (p < 0.001), education levels (p < 0.05), the duration of anti-epidemic measures (p < 0.05), and age (p < 0.05), while no significant differences were observed in terms of gender (p > 0.05). Several risk factors contributing to the mental disorder burden among Chinese overseas students during the pandemic were identified, including the seriousness of the epidemic in their residential area, the apprehension of getting infected, anxieties regarding academic performance, the infection control policies implemented by the host government, preventive measures taken locally to counter the epidemic, and challenges encountered in returning to their home country. CONCLUSION: Given the significant challenges in mental health faced by Chinese overseas students during the COVID-19 crisis, addressing their specific needs and implementing tailored measures is imperative. Future public health emergencies should consider the potential mental disorders and disease risks faced by Chinese overseas students. By providing comprehensive support and targeted interventions, policymakers, educational institutions, and healthcare providers can help mitigate the adverse psychological effects and promote the well-being of this vulnerable population.

Effects of physical activity on Chinese overseas students' mental health during the COVID-19: A multi-country cross-sectional analysis.

BACKGROUND: COVID-19 caused severe effects on the psychological well-being of Chinese students overseas (COS). Physical activity (PA) is critical to strengthen immunity, prevent infection, and reduce the psychological burden caused by COVID-19. However, there is a severe lack of effective PA intervention for mental health in most countries, and COS have limited access to mental healthcare during the pandemic. OBJECTIVE: We aim to examine the effects of PA on COS' mental health during the pandemic abroad and to better understand that certain types of PA might be associated with a greater reduction in psychological burdens during the pandemic. METHODS AND RESULTS: In a multi-country cross-sectional analysis, a questionnaire was distributed to COS living in 37 foreign countries via WeChat Subscription using a snowball sampling strategy. A total of 10,846 participants were included. Descriptive statistics and Binary logistic regression analysis were used for statistical analysis. We found that COS had negative psychology during the pandemic, especially with fear (2.90, 95% CI 2.88-2.92), anxiety (2.84, 95% CI 2.82-2.85), and stress (2.71, 95% CI 2.69-2.73). PA had meaningful effects on reducing COS self-reported mental health burdens (3.42, 95% CI 3.41-3.44) during the pandemic. The largest associations were seen for recreational and home-based PA (i.e., family games, home aerobic exercise), individual outdoor PA (i.e., walking or running, rope skipping), and PA with a duration of 30 to 70 min per session at frequencies of 4 to 6 times and a total of 150 to 330 min of moderate and vigorous intensity per week tends to be an optimal choice during social distancing times. CONCLUSIONS: COS had several poor mental health conditions during the pandemic. The improvement of PA on COS' psychology was positively effective during the pandemic. Specific types, intensities, durations, and frequencies of PA might have advantages over others for improving COS' mental health during periods of public health emergencies, and the topic may merit interventional study to reveal multiple factors causing COS' psychological burdens and enrich the PA forms for all COS' mental health improvement (i.e., infected, recovered, and asymptomatic COS).

Run-up speed and jumping ground reaction force of male elite gymnasts on vault in China.

Background: A high run-up speed and a big jumping ground reaction force are crucial to perform difficult movements and improving the quality of movement performance in the competition vault. However, the relationship between performance in the competition vault and run-up speeds, as well as jumping ground reaction force, still needs to be discovered in detail. Objective: We aimed to investigate the interrelations between different run-up speeds and jumping ground reaction force, and to explore the different requirements of performing different vault styles as well as difficult movements on run-up speed and jumping ground reaction force. Methods: The data, including vaulting run-up speed and jumping ground reaction force of 30 Chinese male elite gymnasts of performance testing, were analyzed. Descriptive statistics and Binary logistic regression analysis were used for statistical analysis. Results: There was no significant difference in the pedaling run-up speed between the Front handspring types and Cartwheel types (p > 0.05). The comparison between interval run-up speeds revealed that the last 5 m run-up speeds were faster during the 25 m run-up distance, and 30 m sprint speed was strongly associated with the 25 m vaulting run-up speed of Handspring and Cartwheel (r = 0.81, p < 0.01). There are significant differences in the jumping ground reaction force of different types and difficult movements (p < 0.01). When the D-score is greater than 4.6, the jumping ground reaction force will increase significantly. Jumping ground reaction force was strongly correlated with 25 m run-up speed (r = 0.715, p < 0.01), last 5 m run-up speed (r = 0.718, p < 0.01), and 30 m sprint speed (r = 0.704, p < 0.01) respectively, but not significantly associated with last 10-5 m run-up speed as well as before the last 10 m run-up speed (p > 0.05). Conclusions: The special requirement for run-up speed and jumping ground reaction force may vary as the difficult vault. Moreover, the optimization of interval run-up speeds and improvement of the 25 m run-up speed may contribute to the bigger jumping ground reaction force and increase the potential to perform more difficult Handspring/Cartwheel vaults. The topic may merit an interventional study to optimize run-up rhythm and improve lower limb strength for achieving higher run-up speeds and bigger jumping ground reaction force within the limited run-up distance to perform more difficult vaults for male elite gymnasts in China.

PA during the COVID-19 outbreak in China: a cross-sectional study.

COVID-19 has undergone several mutations and is still spreading in most countries now. PA has positive benefits in the prevention of COVID-19 infection and counteracting the negative physical and mental effects caused by COVID-19. However, relevant evidence has indicated a high prevalence of physical inactivity among the general population, which has worsened due to the outbreak of the pandemic, and there is a severe lack of exercise guidance and mitigation strategies to advance the knowledge and role of PA to improve physical and mental health in most countries during the epidemic. This study surveyed the effects of COVID-19 on PA in Chinese residents during the pandemic and provided important reference and evidence to inform policymakers and formulate policies and planning for health promotion and strengthening residents' PA during periods of public health emergencies. ANOVA, Kolmogorov-Smirnov, the chi-square test and Spearman correlation analysis were used for statistical analysis. A total of 14,715 participants were included. The results show that nearly 70% of Chinese residents had inadequate PA (95%CI 58.0%-82.19%) during the COVID-19 outbreak, which was more than double the global level (27.5%, 95%CI 25.0%-32.2%). The content, intensity, duration, and frequency of PA were all affected during the period of home isolation, and the types of PA may vary among different ages. The lack of physical facilities and cultural environment is the main factor affecting PA. However, there was no significant correlation between insufficient PA and the infection rate. During the period of home isolation and social distance of epidemic prevention, it is necessary to strengthen the scientific remote network monitoring and guidance for the process of PA in China.

Association Between Physical Exercise and Mental Health During the COVID-19 Outbreak in China: A Nationwide Cross-Sectional Study.

The COVID-19 has undergone several mutations, and caused deleterious effects on physical and mental health of people worldwide. Whilst physical exercise is known for its positive effect on enhancing immunity and reducing the negative consequences of unhealthy emotional states caused by the pandemic; there is a severe lack of psychological exercise intervention measures and mitigation strategies to advance the knowledge and role of physical exercise to improve mental health in most countries. This study surveyed the association between physical exercise and mental health burden during the COVID-19 outbreak in China to better understand the influence of different physical exercise types on reducing mental health burden during the pandemic. ANOVA, binary logistic regression, the chi-square test, and Spearman's correlation analysis were used for statistical analysis. 14,715 participants were included. The results showed that Chinese residents had several poor mental health conditions during the COVID-19 outbreak. And there was a significant positive correlation between the extent of adverse effects on mental health and provincial proportions of confirmed COVID-19 cases (r = 0.365, p < 0.05). Some main factors caused an unhealthy psychological status, including epidemic severity (62.77%, 95% CI 58.62-65.64%), prolonged home quarantine (60.84%, 95% CI 58.15-63.25%), spread of large amounts of negative information about COVID-19 in the media (50.78%, 95% CI 47.46-53.15%), limitations in daily life and social interaction (45.93%, 95%CI 42.46-47.55%), concerns about students' learning (43.13%, 95% CI 40.26-45.48%), and worries about being infected (41.13%, 95% CI 39.16-45.23%). There was a significant association between physical exercise and mental health. The largest associations were seen for home-based group entertainment exercise (i.e., family games, rope skipping, and badminton), Chinese traditional sports (i.e., Chinese martial arts, Taijiquan and Qigong), and popular sports (i.e., yoga, video dancing, sensory-motor games, and whole-body vibration), as well as durations of 30-60 min per session, frequencies of three to five times per week and a total of 120-270 min of moderate-intensity exercise weekly during the COVID-19 outbreak (p < 0.05).