Identification and experimental validation of key m6A modification regulators as potential biomarkers of osteoporosis.

Osteoporosis (OP) is a severe systemic bone metabolic disease that occurs worldwide. During the coronavirus pandemic, prioritization of urgent services and delay of elective care attenuated routine screening and monitoring of OP patients. There is an urgent need for novel and effective screening diagnostic biomarkers that require minimal technical and time investments. Several studies have indicated that N6-methyladenosine (m6A) regulators play essential roles in metabolic diseases, including OP. The aim of this study was to identify key m6A regulators as biomarkers of OP through gene expression data analysis and experimental verification. GSE56815 dataset was served as the training dataset for 40 women with high bone mineral density (BMD) and 40 women with low BMD. The expression levels of 14 major m6A regulators were analyzed to screen for differentially expressed m6A regulators in the two groups. The impact of m6A modification on bone metabolism microenvironment characteristics was explored, including osteoblast-related and osteoclast-related gene sets. Most m6A regulators and bone metabolism-related gene sets were dysregulated in the low-BMD samples, and their relationship was also tightly linked. In addition, consensus cluster analysis was performed, and two distinct m6A modification patterns were identified in the low-BMD samples. Subsequently, by univariate and multivariate logistic regression analyses, we identified four key m6A regulators, namely, METTL16, CBLL1, FTO, and YTHDF2. We built a diagnostic model based on the four m6A regulators. CBLL1 and YTHDF2 were protective factors, whereas METTL16 and FTO were risk factors, and the ROC curve and test dataset validated that this model had moderate accuracy in distinguishing high- and low-BMD samples. Furthermore, a regulatory network was constructed of the four hub m6A regulators and 26 m6A target bone metabolism-related genes, which enhanced our understanding of the regulatory mechanisms of m6A modification in OP. Finally, the expression of the four key m6A regulators was validated in vivo and in vitro, which is consistent with the bioinformatic analysis results. Our findings identified four key m6A regulators that are essential for bone metabolism and have specific diagnostic value in OP. These modules could be used as biomarkers of OP in the future.

Protein post-translational modification in SARS-CoV-2 and host interaction.

SARS-CoV-2 can cause lung diseases, such as pneumonia and acute respiratory distress syndrome, and multi-system dysfunction. Post-translational modifications (PTMs) related to SARS-CoV-2 are conservative and pathogenic, and the common PTMs are glycosylation, phosphorylation, and acylation. The glycosylation of SARS-CoV-2 mainly occurs on spike (S) protein, which mediates the entry of the virus into cells through interaction with angiotensin-converting enzyme 2. SARS-CoV-2 utilizes glycans to cover its epitopes and evade the immune response through glycosylation of S protein. Phosphorylation of SARS-CoV-2 nucleocapsid (N) protein improves its selective binding to viral RNA and promotes viral replication and transcription, thereby increasing the load of the virus in the host. Succinylated N and membrane(M) proteins of SARS-CoV-2 synergistically affect virus particle assembly. N protein regulates its affinity for other proteins and the viral genome through acetylation. The acetylated envelope (E) protein of SARS-CoV-2 interacts with bromodomain-containing protein 2/4 to influence the host immune response. Both palmitoylation and myristoylation sites on S protein can affect the virus infectivity. Papain-like protease is a domain of NSP3 that dysregulates host inflammation by deubiquitination and impinges host IFN-I antiviral immune responses by deISGylation. Ubiquitination of ORF7a inhibits host IFN-α signaling by blocking STAT2 phosphorylation. The methylation of N protein can inhibit the formation of host stress granules and promote the binding of N protein to viral RNA, thereby promoting the production of virus particles. NSP3 macrodomain can reverse the ADP-ribosylation of host proteins, and inhibit the cascade immune response with IFN as the core, thereby promoting the intracellular replication of SARS-CoV-2. On the whole, PTMs have fundamental roles in virus entry, replication, particle assembly, and host immune response. Mutations in various SARS-CoV-2 variants, which lead to changes in PTMs at corresponding sites, cause different biological effects. In this paper, we mainly reviewed the effects of PTMs on SARS-CoV-2 and host cells, whose application is to inform the strategies for inhibiting viral infection and facilitating antiviral treatment and vaccine development for COVID-19.

Protein post-translational modification in SARS-CoV-2 and host interaction

SARS-CoV-2 can cause lung diseases, such as pneumonia and acute respiratory distress syndrome, and multi-system dysfunction. Post-translational modifications (PTMs) related to SARS-CoV-2 are conservative and pathogenic, and the common PTMs are glycosylation, phosphorylation, and acylation. The glycosylation of SARS-CoV-2 mainly occurs on spike (S) protein, which mediates the entry of the virus into cells through interaction with angiotensin-converting enzyme 2. SARS-CoV-2 utilizes glycans to cover its epitopes and evade the immune response through glycosylation of S protein. Phosphorylation of SARS-CoV-2 nucleocapsid (N) protein improves its selective binding to viral RNA and promotes viral replication and transcription, thereby increasing the load of the virus in the host. Succinylated N and membrane(M) proteins of SARS-CoV-2 synergistically affect virus particle assembly. N protein regulates its affinity for other proteins and the viral genome through acetylation. The acetylated envelope (E) protein of SARS-CoV-2 interacts with bromodomain-containing protein 2/4 to influence the host immune response. Both palmitoylation and myristoylation sites on S protein can affect the virus infectivity. Papain-like protease is a domain of NSP3 that dysregulates host inflammation by deubiquitination and impinges host IFN-I antiviral immune responses by deISGylation. Ubiquitination of ORF7a inhibits host IFN-α signaling by blocking STAT2 phosphorylation. The methylation of N protein can inhibit the formation of host stress granules and promote the binding of N protein to viral RNA, thereby promoting the production of virus particles. NSP3 macrodomain can reverse the ADP-ribosylation of host proteins, and inhibit the cascade immune response with IFN as the core, thereby promoting the intracellular replication of SARS-CoV-2. On the whole, PTMs have fundamental roles in virus entry, replication, particle assembly, and host immune response. Mutations in various SARS-CoV-2 variants, which lead to changes in PTMs at corresponding sites, cause different biological effects. In this paper, we mainly reviewed the effects of PTMs on SARS-CoV-2 and host cells, whose application is to inform the strategies for inhibiting viral infection and facilitating antiviral treatment and vaccine development for COVID-19.

Epidemiological characteristics of COVID-19 in Shanxi Province, China

The aim of this study is to analyze the epidemiological trend and characteristics of 2019 coronavirus diseases (COVID-19) during January 22 to February 28 in 2020 in Shanxi Province to provide scientific basis for epidemic prevention and control. The COVID-19 data were obtained from official website of Health Commission of Shanxi Province and other media. Descriptive epidemiological methods were used to analyze the characteristics of cases. The number of new confirmed cases in Shanxi Province appeared an inflection point on February 8(12). By February 28, 2020, the cumulative incidence of COVID-19 in Shanxi Province was 0.36/100,000, and the proportion of cured and discharged patients was 84.85%. The cumulative incidence was 0.29/100,000 in females and 0.42/100,000 in males, with significant difference (X2=4.866, P < 0.05). The confirmed cases were mainly concentrated in Jinzhong (27.82%), Yuncheng (14.29%) and Taiyuan (15.04%). Most cases had a history of travel or residence in other provinces. In conclusion, the incidence of COVID-19 is decreasing, however, it is necessary to take measures to prevent the imported cases and pay close attention to the origin and destination of the floating population.

Etesevimab in combination with JS026 neutralizing SARS-CoV-2 and its variants.

The neutralizing antibody is a potential therapeutic for the ongoing COVID-19 pandemic. As an antiviral agent, numerous mAbs recognize the epitopes that overlap with ACE2-binding sites in the SARS-CoV-2-RBD. Some studies have shown that residual changes on the spike protein can significantly decrease the efficiency of neutralizing antibodies. To address this issue, a therapeutic cocktail could be an effective countermeasure. In the present study, we isolated a fully human neutralizing antibody, JS026, from a convalescent patient. The comparative analysis revealed that JS026 binding to SARS-CoV-2-RBD mainly located between epitopes for class 2 and class 3 mAbs as opposed to that of class 1 (etesevimab) antibodies. A cocktail of etesevimab and JS026 increased neutralizing efficacy against both wild-type SARS-CoV-2 and the recent emergence of Alpha, Beta, Gamma, and Delta variants. JS026 and the cocktail reduced virus titers in the infected lungs of hACE2 transgenic mice and relieved pathological changes. These findings would benefit antibody-based therapeutic countermeasures in the treatment of COVID-19.

Impact of COVID-19 on presentation, staging, and treatment of head and neck mucosal squamous cell carcinoma.

OBJECTIVES: During the COVID-19 pandemic, maintenance of safe and timely oncologic care has been challenging. The goal of this study is to compare presenting symptoms, staging, and treatment of head and neck mucosal squamous cell carcinoma during the pandemic with an analogous timeframe one year prior. MATERIALS AND METHODS: Retrospective cohort study at a single tertiary academic center of new adult patients evaluated in a head and neck surgical oncology clinic from March -July 2019 (pre-pandemic control) and March - July 2020 (COVID-19 pandemic). RESULTS: During the pandemic, the proportion of patients with newly diagnosed malignancies increased by 5%, while the overall number of new patients decreased (n = 575) compared to the control year (n = 776). For patients with mucosal squamous cell carcinoma (SCC), median time from referral to initial clinic visit decreased from 11 days (2019) to 8 days (2020) (p = 0.0031). There was no significant difference in total number (p = 0.914) or duration (p = 0.872) of symptoms. During the pandemic, patients were more likely to present with regional nodal metastases (adjusted odds ratio (OR) 2.846, 95% CI 1.072-3.219, p = 0.028) and more advanced clinical nodal (N) staging (p = 0.011). No significant difference was seen for clinical tumor (T) (p = 0.502) or metastasis (M) staging (p = 0.278). No significant difference in pathologic T (p = 0.665), or N staging (p = 0.907) was found between the two periods. CONCLUSION: Head and neck mucosal SCC patients presented with more advanced clinical nodal disease during the early months of the COVID-19 pandemic despite no change in presenting symptoms.

Clinical Characteristics of Patients with Severe and Critical COVID-19 in Wuhan: A Single-Center, Retrospective Study.

INTRODUCTION: This retrospective, single-center study was performed to systemically describe the characteristics and outcomes of patients with severe and critical coronavirus disease 2019 (COVID-19) in Wuhan, analyze the risk factors, and propose suggestions for clinical diagnosis and treatment to guide the subsequent clinical practice. METHODS: A total of 753 consecutive patients with COVID-19 admitted to the West Campus of Wuhan Union Hospital from January 22, 2020 to May 7, 2020 were enrolled in this study. Demographic, clinical, laboratory, and outcome data were extracted from the electronic medical records of Wuhan Union Hospital and were exhaustively analyzed using R (version 3.6.1). RESULTS: A total of 493 severe and 228 critical cases out of 753 COVID-19 cases were considered in this study. Among the critical cases, the death rate was 79.4%, and age was a risk factor for death. Compared to the severe disease group, the critical disease group had higher white blood cell (WBC) and neutrophil counts and a decreased lymphocyte count at admission. Compared to early death cases (death within 1 week after admission), a more prolonged course of the disease was associated with a higher risk of hypoproteinemia, liver injury, thrombocytopenia, anemia, disseminated intravascular coagulation (DIC), coagulation disorders, acute kidney injury (AKI), and infection. Higher creatine kinase (CK) and lactate dehydrogenase (LDH) levels were related to early death events, but univariate and multivariate analyses confirmed only LDH as an independent predictor of early death. Notably, anticoagulation therapy was associated with an improved prognosis of critical cases in this cohort. CONCLUSION: Our results showed large differences between patients with severe and critical COVID-19. During the course of COVID-19 in the critical disease group, the incidence of hypoproteinemia, anemia, thrombocytopenia, and coagulation disorders increased significantly, which highlighted the importance of medical care in the first week after admission. LDH could act as an independent predictor of early death in critical cases, and anticoagulation therapy was correlated with an improved prognosis of patients with critical COVID-19.