Applications and prospects of cryo-EM in drug discovery.

Drug discovery is a crucial part of human healthcare and has dramatically benefited human lifespan and life quality in recent centuries, however, it is usually time- and effort-consuming. Structural biology has been demonstrated as a powerful tool to accelerate drug development. Among different techniques, cryo-electron microscopy (cryo-EM) is emerging as the mainstream of structure determination of biomacromolecules in the past decade and has received increasing attention from the pharmaceutical industry. Although cryo-EM still has limitations in resolution, speed and throughput, a growing number of innovative drugs are being developed with the help of cryo-EM. Here, we aim to provide an overview of how cryo-EM techniques are applied to facilitate drug discovery. The development and typical workflow of cryo-EM technique will be briefly introduced, followed by its specific applications in structure-based drug design, fragment-based drug discovery, proteolysis targeting chimeras, antibody drug development and drug repurposing. Besides cryo-EM, drug discovery innovation usually involves other state-of-the-art techniques such as artificial intelligence (AI), which is increasingly active in diverse areas. The combination of cryo-EM and AI provides an opportunity to minimize limitations of cryo-EM such as automation, throughput and interpretation of medium-resolution maps, and tends to be the new direction of future development of cryo-EM. The rapid development of cryo-EM will make it as an indispensable part of modern drug discovery.

Shedding of SARS-CoV-2 for 85 Days in COVID-19 Patients With Type 2 Diabetes Mellitus and Lung Metastasis: A Case Report.

Background: COVID-19 (coronavirus disease 2019) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) seriously endangers people's lives. The variation in SARS-CoV-2 makes the research and development of vaccines and specific drugs particularly important. However, the prevention and diagnosis of COVID-19 cannot be underestimated in the control of the epidemic. Case Presentation: We introduced a 65-year-old female patient who was diagnosed with COVID-19. The SARS-CoV-2 nucleic acid test result of this patient was positive again during treatment. It took 85 days from the first symptom to the final cure. According to the known reports, she is currently the patient with the longest virus shedding in Sichuan Province, China. Due to the patient's special condition, she was treated in four hospitals before and after, and she was diagnosed with type 2 diabetes mellitus (T2DM) and right lung metastatic adenocarcinoma. We fully introduced the patient's epidemiological history, diagnosis, testing, and treatment process. The patient was finally discharged from the hospital under the treatment of antiviral, hypoglycaemic, anti-anxiety, and a combination of Chinese and Western medicine. Conclusions: The epidemic is still rampant, and we should not relax our efforts in the prevention and control of viruses. For the elderly, especially those who are suffering from complications or vulnerable to diseases, it is recommended to extend the observation time. Additionally, medical workers should pay attention to the mental state of patients.

Pilot genome-wide association study of antibody response to inactivated SARS-CoV-2 vaccines

Vaccines are a key weapon against the COVID-19 pandemic caused by SARS-CoV-2. However, there are inter-individual differences in immune response to SARS-CoV-2 vaccines and genetic contributions to these differences have barely been investigated. Here, we performed genome-wide association study (GWAS) of antibody levels in 168 inactivated SARS-CoV-2 vaccine recipients. A total of 177 SNPs, corresponding to 41 independent loci, were identified to be associated with IgG, total antibodies or neutral antibodies. Specifically, the rs4543780, the intronic variant of FAM89A gene, was associated with total antibodies level and was annotated as a potential regulatory variant affecting gene expression of FAM89A, a biomarker differentiating bacterial from viral infections in febrile children. These findings might advance our knowledge of the molecular mechanisms driving immunity to SARS-CoV-2 vaccine.

The relationship between online courses and mental health among Chinese children

Background Previous studies on the association of online courses and mental health were mainly conducted in universities, and no study investigated the relationship between characteristics of online courses and children’s mental health in primary and secondary school. This study aimed to explore the association of online courses and children’s mental health in primary and secondary school. Methods A cross-sectional study was conducted through an online survey among 540 primary and secondary school students and their parents in the eastern, central and western region of China from April to May in 2020. Children’s mental health was assessed by the Strengths and Difficulties Questionnaire (SDQ). Borderline mental health problems (SDQ total difficulties score ≥ 16) and mental health problems (SDQ total difficulties score ≥ 20) were defined according to Goodman’s standard. Multivariable linear and logistic regression models were used to examine the association between online courses and children’s mental health. Results Compared with those who did not have problems of online courses, children having the difficulty in understanding the content of online courses had a higher SDQ total difficulties score [β = 1.80, 95% confidence interval (CI): 0.89, 2.71] and a higher risk of borderline mental health problems [odds ratio (OR) = 1.93, 95%CI: 1.07, 3.49], while device or internet connection problems were not significantly associated with children’s mental health. Compared with children who had live courses, those having video-recorded courses had a higher SDQ total difficulties score (β = 0.90, 95%CI: 0.01, 1.80). Children who spent more than 4 h on online courses had a higher SDQ total difficulties score than those of less than or equal to 4 h (β = 0.95, 95%CI: 0.09, 1.81). Conclusion We found that online courses with inappropriate characteristics were associated with children’s mental health. The findings called for the efforts to optimize the online courses and improve children’s mental health. Supplementary Information The online version contains supplementary material available at 10.1186/s12888-022-03976-2.

Promising natural products against SARS-CoV-2: Structure, function, and clinical trials.

The corona virus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus type 2 (SARS-COV-2) poses a severe threat to human health and still spreads globally. Due to the high mutation ratio and breakthrough infection rate of the virus, vaccines and anti-COVID-19 drugs require continual improvements. Drug screening research has shown that some natural active products can target the critical proteins of SARS-CoV-2, including 3CLpro, ACE2, FURIN, and RdRp, which could produce great inhibitory effects on SARS-COV-2. In addition, some natural products have displayed activities of immunomodulation, antiinflammatory, and antihepatic failure in COVID-19 clinical trials, which may relate to their non-monomeric structures. However, further evaluation and high-quality assessments, including safety verification tests, drug interaction tests, and clinical trials, are needed to substantiate natural products' multi-target and multi-pathway effects on COVID-19. Here, we review the literature on several promising active natural products that may act as vaccine immune enhancers or provide targeted anti-COVID-19 drugs. The structures, mechanisms of action, and research progress of these natural products are analyzed, to hopefully provide effective ideas for the development of targeted drugs that possess better structure, potency, and safety.

Re-emergence of Severe Acute Diarrhea Syndrome Coronavirus (SADS-CoV) in Guangxi, China, 2021 (preprint)

Severe acute diarrhea syndrome coronavirus (SADS-CoV) has had a major impact on the swine industry in China, but has not been detected since 2019. Using real-time qPCR and metagenomic surveillance we identified SADS-CoV in a pig farm experiencing diarrheal disease. Genomic analysis supported the undetected circulation of SADS-CoV since 2019.

The effect of potential factors on all-cause and cause-specific and mortality: a pre-COVID-19 period review (preprint)

BackgroundAbout 3 million people die every year in USA. In order to provide a general direction and background for subsequent research and development in this field, we reviewed the studies about impact of potential factors associated with the main causes of mortality and all-cause mortality. MethodResearches are selected by PubMed website for last 15 years with published language of English. The leading cause of death were published by CDC in 2020 (excluded COVID-19) including the ten natural mortalities and unnatural mortality. We summarized the potential factors associated with the mortality and sorted them by "positive/negative effect" and "long-term/short-term effect". ResultAmong risk factors, the factors of depression, unhealthy diet, overweight and obesity and other similar factors increase the mortality of main leading natural causes. Among protective factors, the factors of physical activity, nut intake, chocolate consumption were associated with the reduced mortality of multiple diseases. We also found that some factors possess bidirectional influence on different diseases or even one disease. The gender of female negatively affects mortality of diabetes, but positively affects cardiovascular diseases. The majority of air pollutants are risk factors for respiratory diseases while ozone possibly reduce the mortality. ConclusionOur review summarized various factors which have positive/negative and long-term/short-term effects on the main mortality of cause-specific and all-caused mortality. Further study is required to investigate the contribution of different variable on mortality.

Shedding of SARS-CoV-2 for 85 Days in COVID-19 Patients With Type 2 Diabetes Mellitus and Lung Metastasis: A Case Report

Background COVID-19 (coronavirus disease 2019) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) seriously endangers people's lives. The variation in SARS-CoV-2 makes the research and development of vaccines and specific drugs particularly important. However, the prevention and diagnosis of COVID-19 cannot be underestimated in the control of the epidemic. Case Presentation We introduced a 65-year-old female patient who was diagnosed with COVID-19. The SARS-CoV-2 nucleic acid test result of this patient was positive again during treatment. It took 85 days from the first symptom to the final cure. According to the known reports, she is currently the patient with the longest virus shedding in Sichuan Province, China. Due to the patient's special condition, she was treated in four hospitals before and after, and she was diagnosed with type 2 diabetes mellitus (T2DM) and right lung metastatic adenocarcinoma. We fully introduced the patient's epidemiological history, diagnosis, testing, and treatment process. The patient was finally discharged from the hospital under the treatment of antiviral, hypoglycaemic, anti-anxiety, and a combination of Chinese and Western medicine. Conclusions The epidemic is still rampant, and we should not relax our efforts in the prevention and control of viruses. For the elderly, especially those who are suffering from complications or vulnerable to diseases, it is recommended to extend the observation time. Additionally, medical workers should pay attention to the mental state of patients.

Community Services and Social Involvement in COVID-19 Governance in Urban China (preprint)

Background: This study explores how the services provided by different types of Chinese communities varied in their impact on the social involvement of their residents during the COVID-19 pandemic. Previous research has shown that services in traditional Chinese communities have supported pandemic governance because of their human resource advantages. However, we argue that the services provided by intelligent communities not only adhered to COVID-19 pandemic governance but also promoted the social involvement of the residents.Methods: Using a case study approach of the intelligent community Fang Xing and the traditional community Qili Tang, both located in Hefei city in Anhui, China, this article compares traditional and intelligent Chinese community services. We conducted 42 in-person interviews (21 residents, 10 volunteers, 11 staff members), 30 telephone interviews (10 residents, 10 volunteers, 10 staff members), and 50 online video interviews (30 residents, 10 volunteers, 10 staff members) from June to August 2020.Results: The findings suggest that while the traditional community decreased its residents’ social involvement by restricting certain services during the pandemic, the intelligent community was able to apply COVID-19 governance measures without restricting its residents’ social involvement. In the traditional community, family members were obliged to take responsibility for daily living services and family care tasks. This community often responded slowly when providing required services compared to intelligent communities. The intelligent community contributed greatly to its residents’ social involvement in the process of pandemic governance. It offered an attractive option for residents to act as community service managers and prepared its residents for local-level pandemic governance.Conclusions: This study provides a better understanding of the relationship between community services and residents’ social involvement in terms of the different dimensions of community services. The intelligent community model can act as a reference for international community development during health emergencies.

Chimeric mRNA based COVID-19 vaccine elicits potent neutralizing antibodies and protection against Omicron and Delta (preprint)

The emerging SARS-CoV-2 variants of concern (VOCs) exhibit enhanced transmission and immune escape, reducing the efficacy and effectiveness of the two FDA-approved mRNA vaccines currently in use. Here, we explored various strategies to develop mRNA vaccines that offer potentially safer and wider coverage of VOCs. The initial mouse vaccination results showed that the individual VOC mRNAs carrying furin cleavage mutation induced the generation of neutralizing antibody in a VOC-specific manner. Moreover, we discovered that the antibodies produced from mice immunized with Beta-Furin and Washington (WA)-Furin mRNAs cross-reacted with other VOCs. The broad spectrum of generated nAb was further confirmed when vaccinated mice were challenged with the respective live viruses. However, neither WA-Furin nor Beta-Furin mRNA elicited potent neutralizing activity against the omicron variant. Interestingly, in a mix-and-match booster experiment, omicron-Furin and WA-Furin mRNA elicited comparable protection against omicron. Finally, we tested the concept of bivalent vaccine by introducing the RBD of Delta strain into the intact S antigen of Omicron. The chimeric mRNA induces potent and broadly acting nAb against Omicron and Delta, which paves the way to develop vaccine candidate to target emerging variants in the future.

Potential Genes Associated with COVID-19 and Comorbidity.

Hypertension, diabetes mellitus, and coronary artery disease are common comorbidities and dangerous factors for infection and serious COVID-19. Polymorphisms in genes associated with comorbidities may help observe susceptibility and disease severity variation. However, specific genetic factors and the extent to which they can explain variation in susceptibility of severity are unclear. Therefore, we evaluated candidate genes associated with COVID-19 and hypertension, diabetes mellitus, and coronary artery disease. In particular, we performed searches against OMIM, NCBI, and other databases, protein-protein interaction network construction, and GO and KEGG pathway enrichment analyses. Results showed that the associated overlapping genes were TLR4, NLRP3, MBL2, IL6, IL1RN, IL1B, CX3CR1, CCR5, AGT, ACE, and F2. GO and KEGG analyses yielded 302 GO terms (q < 0.05) and 29 signaling pathways (q < 0.05), respectively, mainly including coronavirus disease-COVID-19 and cytokine-cytokine receptor interaction. IL6 and AGT were central in the PPI, with 8 and 5 connections, respectively. In this study, we identified 11 genes associated with both COVID-19 and three comorbidities that may contribute to infection and disease severity. The key genes IL6 and AGT are involved in regulating immune response, cytokine activity, and viral infection. Therefore, RAAS inhibitors, AGT antisense nucleotides, cytokine inhibitors, vitamin D, fenofibrate, and vaccines regulating non-immune and immune factors could be potential strategies to prevent and cure COVID-19. The study provides a basis for further investigation of genes and pathways with predictive value for the risk of infection and prognosis and could help guide drug and vaccine development to improve treatment efficacy and the development of personalised treatments, especially for COVID-19 individuals with common comorbidities.

Case Report: Genomic Characteristics of the First Known Case of SARS-CoV-2 Imported From Spain to Sichuan, China.

The pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been basically under control in China since March 2020, but the import of domestic SARS-CoV-2 has begun to increase. This study reported the first case of asymptomatic SARS-CoV-2 infection imported from Spain into Sichuan Province, China, on March 11, 2020. The infected male had a body temperature of 37.5°C, normal blood oxygen saturation levels, and a computed tomography (CT) examination showed that his lungs had no shadows. However, a throat swab from the subject tested positive for SARS-CoV-2 using qPCR assay. In this study, we conducted transcriptome sequencing on respiratory throat swabs from the subject and found that the dominant SARS-CoV-2 sequence (Gene Bank ID: MW301121) was a spike protein D614G mutant strain, which is currently popular throughout world. We downloaded and analyzed SARS-CoV-2 sequences collected from cases in China and Spain for comparison and tracing purposes. After March 11, 2020, the Chinese domestic clade was naturally divided into the imported SARS-CoV-2 D614G mutant strain and evolutionarily-related similar sequences and that of sequences collected in the original Wuhan area. The sequence reported in this study was located on a small branch, far from the evolution of Wuhan sequences. As expected, the identified sequence was closely related to the evolution of the SARS-CoV-2 D614G mutant strain circulating in Spain.

Potential therapeutic effect and methods of traditional Chinese medicine on COVID-19-induced depression: A review.

COVID-19 (coronavirus) has spread all over the world with a high infection rate. Currently, there are no targeted therapeutic drugs for COVID-19 as well as for stress induced by COVID-19. The unpredictable events of COVID-19 can trigger feelings of fear, worry, or unease in people, leading to stress-related disorders such as depression and anxiety. It has been reported that individuals, including COVID-19 patients, medical staff, and ordinary people, are under both physical and psychological pressure, and many of them have developed depression or anxiety during this pandemic. Traditional Chinese medicine (TCM) has been widely used in treating depression with relatively better safety and efficacy and may have an important role in treating stress-related disorders induced by COVID-19. In this review, we collected the common TCM treatment methods including Qigong, Acupuncture, Five Elements Musical Therapy, Five Elements Emotional Therapy, and Chinese herbal medicine from the databases of PubMed and the China National Knowledge Internet to illustrate the effect of TCM on depression. The better knowledge of TCM and implementation of TCM in COVID-19 clinics may help to effectively improve depression induced by COVID-19, may assist people to maintain a healthy physical and mental quality, and may alleviate the current shortage of medical resources.

Chinese College Students' Stress and Anxiety Levels Under COVID-19.

The outbreak of COVID-19 at the end of 2019 has had a significant impact on people. While attention is paid to the immense physical harm it has caused, the psychological impact should not be underestimated. The main purpose of this study was to explore the stress, anxiety, and depression levels of different groups of college students during the COVID-19 pandemic. We conducted an online questionnaire survey of college students by using the Perceived Stress Scale (PSS-10), the Patient Health Questionnaire-9 items (PHQ-9), and the Self-rating Anxiety Scale (SAS). A total of 1,586 questionnaires were collected and analyzed in R language. The results showed that students with moderate to severe stress (PSS-10 ≥ 14) accounted for 67.50%; the detection rate of depression (PHQ-9 ≥ 5) reached 43.77%; and 20.60% of students had anxiety (SAS standard score ≥ 50). There were significant differences in PSS-10/SAS among different genders, majors, whether returning to school or not, and those with different psychological experiences (negative or positive, P < 0.05). It is notable that the median of female, medical student, non-resumption of schooling, and negative experience was higher than that of positive experience (P < 0.05). The results of principal component analysis showed that there were significant differences in PHQ-9, PSS-10, and SAS between the resumption of schooling group and the non-resumption group. Therefore, it is inferred that the stress and anxiety level of college students during the COVID-19 pandemic is generally high, especially for those who have not yet resumed school. Long-term negative emotions can easily lead to serious mental diseases such as cognitive impairment. Education departments should attach great importance to the mental health of college students, and it is necessary to provide precise psychological interventions for groups experiencing greater pressure levels and marked anxiety and depression.

SARS-CoV-2 and SARS-CoV: Virtual screening of potential inhibitors targeting RNA-dependent RNA polymerase activity (NSP12).

Since the outbreak of severe acute respiratory syndrome (SARS) in 2003, the harm caused by coronaviruses to the world cannot be underestimated. Recently, a novel coronavirus (severe acute respiratory syndrome coronavirus-2 [SARS-CoV-2]) initially found to trigger human severe respiratory illness in Wuhan City of China in 2019, has infected more than six million people worldwide by 21 June 2020, and which has been recognized as a public health emergency of international concern as well. And the virus has spread to more than 200 countries around the world. However, the effective drug has not yet been officially licensed or approved to treat SARS-Cov-2 and SARS-Cov infection. NSP12-NSP7-NSP8 complex of SARS-CoV-2 or SARS-CoV, essential for viral replication and transcription, is generally regarded as a potential target to fight against the virus. According to the NSP12-NSP7-NSP8 complex (PDB ID: 7BW4) structure of SARS-CoV-2 and the NSP12-NSP7-NSP8 complex (PDB ID: 6NUR) structure of SARS-CoV, NSP12-NSP7 interface model, and NSP12-NSP8 interface model were established for virtual screening in the present study. Eight compounds (Nilotinib, Saquinavir, Tipranavir, Lonafarnib, Tegobuvir, Olysio, Filibuvir, and Cepharanthine) were selected for binding free energy calculations based on virtual screening and docking scores. All eight compounds can combine well with NSP12-NSP7-NSP8 in the crystal structure, providing drug candidates for the treatment and prevention of coronavirus disease 2019 and SARS.

Predicting the Animal Susceptibility and Therapeutic Drugs to SARS-CoV-2 Based on Spike Glycoprotein Combined With ACE2.

Recently, a few animals have been frequently reported to have been diagnosed with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Whether they are SARS-CoV-2 intermediate hosts is worthy of great attention. The interaction of SARS-CoV-2 spike protein and its acceptor protein ACE2 is an important issue in determining viral host range and cross-species infection, while the binding capacity of Spike protein to ACE2 of different species is unknown. Here, we used the atomic structure model of SARS-CoV-2 and human ACE2 to assess the receptor utilization capacity of ACE2s from 10 kinds of animals. Results show that chimpanzees, domestic cats and cattles are more susceptible to infection by SARS-CoV-2. Cats in particular, such as pet cats and stray cats, interact very closely with humans, implying the necessity to carefully evaluate the risk of cats during the current COVID-19 pandemic. Furthermore, based on ACE2(cats)-SARS-CoV-2-RBD model, through high-throughput screening methods using a pool of 30,000 small molecules, eight compounds were selected for binding free energy calculations. All the eight compounds can effectively interfere with the binding of ACE2 and Spike protein, especially Nelfinavir, providing drug candidates for the treatment and prevention of SARS-CoV-2, suggesting further assessment of the anti-SARS-CoV-2 activity of these compounds in cell culture. Although we only reported the results of the simulation, and more laboratory and epidemiological investigation are required. Like cats are a risk factor, we can further detect SARS-CoV-2 according to the susceptibility of different animals, find the potential host of infection, and completely cut off the living space of the virus. Especially, cats could be a choice of animal model for screening antiviral drugs or vaccine candidates against SARS-CoV-2.

Current Prevention of COVID-19: Natural Products and Herbal Medicine.

Starting from December 2019, novel coronavirus disease 2019 (COVID-19) pandemic has caused tremendous economic loss and unprecedented health crisis across the globe. While the development of cure is at full speed, less attention and fewer effort have been spent on the prevention of this rapidly spreading respiratory infectious disease. Although so far, several vaccine candidates have advanced into clinical trials, limited data have been released regarding the vaccine efficacy and safety in human, not mention the long-term effectiveness of those vaccines remain as open question yet. Natural products and herbal medicines have been historically used for acute respiratory infection and generally show acceptable toxicity. The favorable stability for oral formulation and ease of scaling up manufacture make it ideal candidate for prophylactic. Hereby, we summarized the most recent advance in SARS-CoV-2 prevention including vaccine development as well as experimental prophylactics. Mainly, we reviewed the natural products showing inhibitory effect on human coronavirus, and discussed the herbal medicines lately used for COVID-19, especially focused on the herbal products already approved by regulatory agency with identifiable patent number. We demonstrated that to fill in the response gap between appropriate treatment and commercially available vaccine, repurposing natural products and herbal medicines as prophylactic will be a vigorous approach to stop or at least slow down SARS-CoV-2 transmission. In the interest of public health, this will lend health officials better control on the current pandemic.