Psychological status of infertile men during the Coronavirus Disease 2019 Pandemic in China: a cross-sectional investigation.

BACKGROUND: The coronavirus disease 2019 (COVID-19) outbreak has had a widespread and profound impact on people's mental health. The factors associated with mental symptoms among men diagnosed with infertility, a disease closely related to psychological conditions, remain unclear. The aim of this study is to investigate the risk factors associated with mental symptoms among infertile Chinese men during the pandemic. RESULTS: A total of 4,098 eligible participants were recruited in this cross-sectional, nationwide study, including 2,034 (49.6%) with primary infertility and 2,064 (50.4%) with secondary infertility. The prevalence of mental health conditions was 36.3%, 39.6%, and 6.7% for anxiety, depression, and post-pandemic stress, respectively. Sexual dysfunction is associated with a higher risk with adjusted odds ratios (ORs) of 1.40 for anxiety, 1.38 for depression, and 2.32 for stress. Men receiving infertility drug therapy displayed a higher risk for anxiety (adjusted OR, 1.31) and depression (adjusted OR, 1.28) symptoms, while those receiving intrauterine insemination had a lower risk of anxiety (adjusted OR, 0.56) and depression (adjusted OR, 0.55) symptoms. CONCLUSION: The COVID-19 pandemic has had a significant psychological impact on infertile men. Several psychologically vulnerable populations were identified, including individuals with sexual dysfunction, respondents receiving infertility drug therapy, and those experiencing control measures for COVID-19. The findings provide a comprehensive profile of the mental health status of infertile Chinese men during the COVID-19 outbreak and provide potential psychological intervention strategies.

RéSUMé: CONTEXTE: L'épidémie de maladie à coronavirus 2019 (COVID-19) a eu un impact étendu et profond sur la santé mentale des gens. Les facteurs associés aux symptômes mentaux chez les hommes diagnostiqués comme infertiles, une maladie étroitement liée aux conditions psychologiques, restent flous. L'objectif de cette étude est d'étudier les facteurs de risque associés aux symptômes mentaux chez les hommes chinois infertiles pendant la pandémie. RéSULTATS: Au total, 4 098 participants admissibles ont été recrutés dans cette étude transversale à l'échelle nationale, dont 2 034 (49,6%) présentaient une infertilité primaire et 2 064 (50,4%) une infertilité secondaire. La prévalence des problèmes de santé mentale était respectivement de 36,3 %, 39,6 % et 6,7 % pour l'anxiété, la dépression, et le stress postpandémique. La dysfonction sexuelle est associée à un risque plus élevé avec des odds ratios ajustés (OR) de 1,40 pour l'anxiété, 1,38 pour la dépression et 2,32 pour le stress. Les hommes recevant un traitement médicamenteux contre l'infertilité présentaient un risque plus élevé de symptômes d'anxiété (OR ajusté, 1,31) et de dépression (OR ajusté, 1,28), alors que ceux dont le traitement consistait à faire des inséminations intra-utérines présentaient un risque plus faible de symptômes d'anxiété (OR ajusté, 0,56) et de dépression (OR ajusté, 0,55). CONCLUSIONS: La pandémie de COVID-19 a eu un impact psychologique important sur les hommes infertiles. Plusieurs populations psychologiquement vulnérables ont été identifiées, notamment les personnes souffrant de dysfonction sexuelle, les hommes recevant un traitement médicamenteux contre l'infertilité, et ceux subissant des mesures de contrôle de la COVID-19. Les résultats fournissent un profil complet de l'état de santé mentale des hommes Chinois infertiles pendant l'épidémie de COVID-19 et fournissent des stratégies potentielles d'intervention psychologique.

Chicken intestinal microbiota modulation of resistance to nephropathogenic infectious bronchitis virus infection through IFN-I.

BACKGROUND: Mammalian intestinal microbiomes are necessary for antagonizing systemic viral infections. However, very few studies have identified whether poultry commensal bacteria play a crucial role in protecting against systemic viral infections. Nephropathogenic infectious bronchitis virus (IBV) is a pathogenic coronavirus that causes high morbidity and multiorgan infection tropism in chickens. RESULTS: In this study, we used broad-spectrum oral antibiotics (ABX) to treat specific pathogen free (SPF) chickens to deplete the microbiota before infection with nephropathogenic IBV to analyze the impact of microbiota on IBV infections in vivo. Depletion of the SPF chicken microbiota increases pathogenicity and viral burden following IBV infection. The gnotobiotic chicken infection model further demonstrated that intestinal microbes are resistant to nephropathogenic IBV infection. In addition, ABX-treated chickens showed a severe reduction in macrophage activation, impaired type I IFN production, and IFN-stimulated gene expression in peripheral blood mononuclear cells and the spleen. Lactobacillus isolated from SPF chickens could restore microbiota-depleted chicken macrophage activation and the IFNAR-dependent type I IFN response to limit IBV infection. Furthermore, exopolysaccharide metabolites of Lactobacillus spp. could induce IFN-ß. CONCLUSIONS: This study revealed the resistance mechanism of SPF chicken intestinal microbiota to nephropathogenic IBV infection, providing new ideas for preventing and controlling nephropathogenic IBV. Video abstract.

Exploring psychological resilience of entrepreneurial college students for post-pandemic pedagogy: The mediating role of self-efficacy

The psychological impact of the COVID-19 epidemic on college students is an important topic. With the entry of the post-epidemic era, how universities can better improve students’ psychological resilience in teaching is the research topic of this article. In the form of a questionnaire survey, some entrepreneurial college students investigated the loneliness and psychological resilience of college students after the outbreak of the epidemic and explored the role of self-efficacy in it. The data is collected online through cooperation with an entrepreneurial event, and the participating students are asked for background information such as colleges, grade, and majors. After collecting this information, they answered a series of simplified scale questions about loneliness, self-efficacy, and psychological resilience. In the end, a total of 200 questionnaires from different universities were collected, and the structural equation model was used to explore the role of self-efficacy. The results show that: loneliness has a significant negative effect on Self-efficacy, β = -0.292, p < 0.001;Self-efficacy has a significant positive effect on psychological resilience, β = 0.556, p < 0.0 01;loneliness has a significant negative effect on psychological resilience, β = -0.244, p < 0.01. Self-Efficacy has a significant intermediate effect in loneliness and psychological resilience, with an effective value of -0.111 and p < 0.01. The results show that this exploratory survey finds it important to provide targeted personal self-efficacy improvement activities for college students with a strong sense of loneliness and to combine school and family education organically to help college students form a healthy and upward mentality to better cope with the unknown and troubles caused by the epidemic, which will help improve the psychological resilience of college students in the epidemic.

Novel SARS‐CoV‐2 Inactivation Formulation Supports Extended COVID‐19 Testing/Surveillance

Background With the spread of highly infectious strains such as the Delta variant of SARS‐CoV‐2, rapid antigen testing and variant tracking are gaining more attention from infectious disease specialists and the general public as essentials for disease control and prevention amidst the COVID‐19 pandemic. The lateral flow based antigen tests provide fast turnaround of results within minutes, but it’s open ‐faced assay format means that the test operators are more prone to accidental exposure to pathogen‐containing samples. The viral inactivation transport media (ITMs) provide much needed protection against exposure to highly transmissive live viruses during sample collection, transport, and storage. However, the current ITMs were designed for PCR tests and share a harsh chemical formulation that denatures protein analytes, making them incompatible with antigen tests. We developed an innovative viral transport media that is designed for a variety of tests, such as antigen testing and PCR. The new formulation can be used to safely inactivate SARS‐CoV‐2 virus while maintaining compatibility with many different formats beyond rt‐PCR. Design To evaluate the viral inactivation performance of the novel inactivation transport media formulation, a cytopathic effect assay was conducted using VERO E6 cells in presence of SARS‐CoV‐2 samples incubated in our novel formulation and log reduction were reported. To assess its compatibility with different SARS‐CoV‐2 related assays, the novel formulation was used as inactivation transport media in antigen, PCR, and NGS based Swab‐Seq tests with known controls. Results The results for the inactivation study confirmed > 3.0 log reduction in viral titer after 30 min exposure in novel transport media formulation and demonstrated 99.5% effectiveness in SARS‐CoV‐2 inactivation. The results for the PCR and antigen test compatibility studies showed comparable and/or superior performance in detection limits for the novel formulation when compared to other sample media. The Swab‐Seq result offers preliminary support on the novel formulation’s compatibility with NGS based assays. Conclusion Using a novel viral transport medium, we were able to completely inactivate the SARS‐CoV‐2 virus. The new formulation was compatible with both nucleic acid and protein assays while protecting cells from infection. This viral transport media could allow more test types to be done from a single specimen, resulting in safer and reliable outcomes. Additionally, it would reduce the need for multiple samples collected from patients while supporting SARS‐CoV‐2 variant tracking via NGS.

Reconsidering treatment guidelines for acute myocardial infarction during the COVID-19 pandemic.

BACKGROUND: COVID-19 affects healthcare resource allocation, which could lead to treatment delay and poor outcomes in patients with acute myocardial infarction (AMI). We assessed the impact of the COVID-19 pandemic on AMI outcomes. METHODS: We compared outcomes of patients admitted for acute ST-elevation MI (STEMI) and non-STEMI (NSTEMI) during a non-COVID-19 pandemic period (January-February 2019; Group 1, n = 254) and a COVID-19 pandemic period (January-February 2020; Group 2, n = 124). RESULTS: For STEMI patients, the median of first medical contact (FMC) time, door-to-balloon time, and total myocardial ischemia time were significantly longer in Group 2 patients (all p < 0.05). Primary percutaneous intervention was performed significantly more often in Group 1 patients than in Group 2 patients, whereas thrombolytic therapy was used significantly more often in Group 2 patients than in Group 1 patients (all p < 0.05). However, the rates of and all-cause 30-day mortality and major adverse cardiac event (MACE) were not significantly different in the two periods (all p > 0.05). For NSTEMI patients, Group 2 patients had a higher rate of conservative therapy, a lower rate of reperfusion therapy, and longer FMC times (all p < 0.05). All-cause 30-day mortality and MACE were only higher in NSTEMI patients during the COVID-19 pandemic period (p < 0.001). CONCLUSIONS: COVID-19 pandemic causes treatment delay in AMI patients and potentially leads to poor clinical outcome in NSTEMI patients. Thrombolytic therapy should be initiated without delay for STEMI when coronary intervention is not readily available; for NSTEMI patients, outcomes of invasive reperfusion were better than medical treatment.

Unsupervised Anomaly Detection in Medical Images with a Memory-augmented Multi-level Cross-attentional Masked Autoencoder (preprint)

Unsupervised anomaly detection (UAD) aims to find anomalous images by optimising a detector using a training set that contains only normal images. UAD approaches can be based on reconstruction methods, self-supervised approaches, and Imagenet pre-trained models. Reconstruction methods, which detect anomalies from image reconstruction errors, are advantageous because they do not rely on the design of problem-specific pretext tasks needed by self-supervised approaches, and on the unreliable translation of models pre-trained from non-medical datasets. However, reconstruction methods may fail because they can have low reconstruction errors even for anomalous images. In this paper, we introduce a new reconstruction-based UAD approach that addresses this low-reconstruction error issue for anomalous images. Our UAD approach, the memory-augmented multi-level cross-attentional masked autoencoder (MemMC-MAE), is a transformer-based approach, consisting of a novel memory-augmented self-attention operator for the encoder and a new multi-level cross-attention operator for the decoder. MemMCMAE masks large parts of the input image during its reconstruction, reducing the risk that it will produce low reconstruction errors because anomalies are likely to be masked and cannot be reconstructed. However, when the anomaly is not masked, then the normal patterns stored in the encoder's memory combined with the decoder's multi-level cross attention will constrain the accurate reconstruction of the anomaly. We show that our method achieves SOTA anomaly detection and localisation on colonoscopy, pneumonia, and covid-19 chest x-ray datasets.

Advances in nucleic acid amplification techniques (NAATs): COVID-19 point-of-care diagnostics as an example.

Achieving superhigh sensitivity is the ultimate goal for bio-detection in modern analytical science and life science. Among variable signal amplification strategies, nucleic acid amplification technologies are revolutionizing the field of bio-detection, providing greater possibilities in novel diagnosis achieving high efficiency, specificity, and cost-effectiveness. Nucleic acid amplification techniques (NAATs), such as Polymerase Chain Reaction (PCR), Rolling Circle Amplification (RCA), Loop-Mediated Isothermal Amplification (LAMP), Recombinase Polymerase Amplification (RPA), CRISPR-related amplification, and others are dominating methods employed in research and clinical settings. They each provide distinctively unique features that can offer desirable performance in terms of sensitivity, specificity, simplicity, stability, and cost. NAATs are in unmet demand in molecular diagnosis, especially in point-of-care scenario. This review will discuss the principles and recent advancements of each NAAT, respectively, revealing their strengths and challenges in achieving rapid and accurate bio-detection with a focus on point-of-care diagnosis. Furthermore, this review will explore the application of each of the technologies through the contemporary COVID-19 pandemic, analyzing their ability in point-of-care diagnosis of the COVID-19 with high sensitivity to emphasize significance of developing NAATs based methods in battling COVID-19. Finally, advantages and potentials of each NAAT in enhancements of sensitivity and specificity in bio-detection from bench side to the bedside will be discussed, aiming for full exploitation of capability of each NAAT. This review will provide novel aspects in the selection and combination of usages of various NAATs based on their distinctive characteristics and limitations. A possible advancing direction of future accurate POCT is also proposed.

Use of personal protective equipment against coronavirus disease 2019 by healthcare professionals in Wuhan, China: cross sectional study.

OBJECTIVE: To examine the protective effects of appropriate personal protective equipment for frontline healthcare professionals who provided care for patients with coronavirus disease 2019 (covid-19). DESIGN: Cross sectional study. SETTING: Four hospitals in Wuhan, China. PARTICIPANTS: 420 healthcare professionals (116 doctors and 304 nurses) who were deployed to Wuhan by two affiliated hospitals of Sun Yat-sen University and Nanfang Hospital of Southern Medical University for 6-8 weeks from 24 January to 7 April 2020. These study participants were provided with appropriate personal protective equipment to deliver healthcare to patients admitted to hospital with covid-19 and were involved in aerosol generating procedures. 77 healthcare professionals with no exposure history to covid-19 and 80 patients who had recovered from covid-19 were recruited to verify the accuracy of antibody testing. MAIN OUTCOME MEASURES: Covid-19 related symptoms (fever, cough, and dyspnoea) and evidence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, defined as a positive test for virus specific nucleic acids in nasopharyngeal swabs, or a positive test for IgM or IgG antibodies in the serum samples. RESULTS: The average age of study participants was 35.8 years and 68.1% (286/420) were women. These study participants worked 4-6 hour shifts for an average of 5.4 days a week; they worked an average of 16.2 hours each week in intensive care units. All 420 study participants had direct contact with patients with covid-19 and performed at least one aerosol generating procedure. During the deployment period in Wuhan, none of the study participants reported covid-19 related symptoms. When the participants returned home, they all tested negative for SARS-CoV-2 specific nucleic acids and IgM or IgG antibodies (95% confidence interval 0.0 to 0.7%). CONCLUSION: Before a safe and effective vaccine becomes available, healthcare professionals remain susceptible to covid-19. Despite being at high risk of exposure, study participants were appropriately protected and did not contract infection or develop protective immunity against SARS-CoV-2. Healthcare systems must give priority to the procurement and distribution of personal protective equipment, and provide adequate training to healthcare professionals in its use.

Effectiveness of inactivated SARS-CoV-2 vaccines against the Delta variant infection in Guangzhou: a test-negative case-control real-world study.

The effectiveness of inactivated SARS-CoV-2 vaccines against the Delta variant, which has been associated with greater transmissibility and virulence, remains unclear. We conducted a test-negative case-control study to explore the vaccine effectiveness (VE) in real-world settings. We recruited participants aged 18-59 years who consisted of SARS-CoV-2 test-positive cases (n = 74) and test-negative controls (n = 292) during the outbreak of the Delta variant in May 2021 in Guangzhou city, China. Vaccination status was compared to estimate The VE of SARS-CoV-2 inactivated vaccines. A single dose of inactivated SARS-CoV-2 vaccine yielded the VE of only 13.8%. After adjusting for age and sex, the overall VE for two-dose vaccination was 59.0% (95% confidence interval: 16.0% to 81.6%) against coronavirus disease 2019 (COVID-19) and 70.2% (95% confidence interval: 29.6-89.3%) against moderate COVID-19 and 100% against severe COVID-19 which might be overestimated due to the small sample size. The VE of two-dose vaccination against COVID-19 reached 72.5% among participants aged 40-59 years, and was higher in females than in males against COVID-19 and moderate diseases. While single dose vaccination was not sufficiently protective, the two-dose dosing scheme of the inactivated vaccines was effective against the Delta variant infection in real-world settings, with the estimated efficacy exceeding the World Health Organization minimal threshold of 50%.

Self-supervised Pseudo Multi-class Pre-training for Unsupervised Anomaly Detection and Segmentation in Medical Images (preprint)

Unsupervised anomaly detection (UAD) methods are trained with normal (or healthy) images only, but during testing, they are able to classify normal and abnormal (or disease) images. UAD is an important medical image analysis (MIA) method to be applied in disease screening problems because the training sets available for those problems usually contain only normal images. However, the exclusive reliance on normal images may result in the learning of ineffective low-dimensional image representations that are not sensitive enough to detect and segment unseen abnormal lesions of varying size, appearance, and shape. Pre-training UAD methods with self-supervised learning, based on computer vision techniques, can mitigate this challenge, but they are sub-optimal because they do not explore domain knowledge for designing the pretext tasks, and their contrastive learning losses do not try to cluster the normal training images, which may result in a sparse distribution of normal images that is ineffective for anomaly detection. In this paper, we propose a new self-supervised pre-training method for MIA UAD applications, named Pseudo Multi-class Strong Augmentation via Contrastive Learning (PMSACL). PMSACL consists of a novel optimisation method that contrasts a normal image class from multiple pseudo classes of synthesised abnormal images, with each class enforced to form a dense cluster in the feature space. In the experiments, we show that our PMSACL pre-training improves the accuracy of SOTA UAD methods on many MIA benchmarks using colonoscopy, fundus screening and Covid-19 Chest X-ray datasets. The code is made publicly available via https://github.com/tianyu0207/PMSACL.

Clinical Factors and Quantitative CT Parameters Associated With ICU Admission in Patients of COVID-19 Pneumonia: A Multicenter Study.

The clinical spectrum of COVID-19 pneumonia is varied. Thus, it is important to identify risk factors at an early stage for predicting deterioration that require transferring the patients to ICU. A retrospective multicenter study was conducted on COVID-19 patients admitted to designated hospitals in China from Jan 17, 2020, to Feb 17, 2020. Clinical presentation, laboratory data, and quantitative CT parameters were also collected. The result showed that increasing risks of ICU admission were associated with age > 60 years (odds ratio [OR], 12.72; 95% confidence interval [CI], 2.42-24.61; P = 0.032), coexisting conditions (OR, 5.55; 95% CI, 1.59-19.38; P = 0.007) and CT derived total opacity percentage (TOP) (OR, 8.0; 95% CI, 1.45-39.29; P = 0.016). In conclusion, older age, coexisting conditions, larger TOP at the time of hospital admission are associated with ICU admission in patients with COVID-19 pneumonia. Early monitoring the progression of the disease and implementing appropriate therapies are warranted.

Microbial and metabolomic analysis of gingival crevicular fluid in general chronic periodontitis patients: lessons for a predictive, preventive, and personalized medical approach.

OBJECTIVES: General chronic periodontitis (GCP) is a bacterial inflammatory disease with complex pathology. Despite extensive studies published on the variation in the oral microbiota and metabolic profiles of GCP patients, information is lacking regarding the correlation between host-bacterial interactions and biochemical metabolism. This study aimed to analyze the oral microbiome, the oral metabolome, and the link between them and to identify potential molecules as useful biomarkers for predictive, preventive, and personalized medicine (PPPM) in GCP. METHODS: In this study, gingival crevicular fluid (GCF) samples were collected from patients with GCP (n = 30) and healthy controls (n = 28). The abundance of oral microbiota constituents was obtained by Illumina sequencing, and the relative level of metabolites was measured by gas chromatography-mass spectrometry. Full-mouth probing depth, clinical attachment loss, and bleeding on probing were recorded as indices of periodontal disease. RESULTS: The relative abundances of 7 phyla and 82 genera differed significantly between the GCP and healthy groups. Seventeen differential metabolites involved in different metabolism pathways were selected based on variable influence on projection values (VIP > 1) and P values (P < 0.05). Through Spearman's correlation analysis, microorganisms, metabolites in GCF, and clinical data together showed a clear trend, and clinical data regarding periodontitis can be reflected in the shift of the oral microbial community and the change in metabolites in GCF. A combination of citramalic acid and N-carbamylglutamate yielded satisfactory accuracy (AUC = 0.876) for the predictive diagnosis of GCP. CONCLUSIONS: Dysbiosis in the polymicrobial community structure and changes in metabolism could be mechanisms underlying periodontitis. The differential microorganisms and metabolites in GCF between periodontitis patients and healthy individuals are possibly biomarkers, pointing to a potential strategy for the prediction, diagnosis, prognosis, and management of personalized periodontal therapy.

Liver Injury Is Related to the Severity and Prognosis of Novel Coronavirus Disease 2019 (preprint)

Background: Previous studies revealed that liver injury is common in the novel coronavirus disease 2019 (COVID-19) patients. However, risk factors of liver injury and whether liver injury is related to the severity or prognosis of COVID-19 is unclarified. Methods: COVID-19 patients were retrospectively recruited from a tertiary hospital in Wuhan, China. General information, past medical history, symptoms, signs, laboratory examination results and clinical outcomes were collected. Incidence and potential risk factors of liver injury were analyzed. Laboratory examination results, incidence of other symptoms and the incidence of the main outcomes, disease progression and death, were compared between patients with or without liver injury. Findings: About 57·7% patients showed liver injury. The incidence of liver injury was higher in male patients. More patients with liver injury were diagnosed as critically ill at admission. Patients with liver injury had higher incidence of dyspnea, lower SpO2 and higher maximum body temperature. They also had many worse laboratory examination results regarding inflammation, cytokines, renal function, coagulation function and myocardial injury. And, the incidence of disease progression and mortality was much higher in patients with liver injury. In further multivariable logistic analysis, direct bilirubin, hs-CRP and NT-proBNP were independent predictors for disease progression, and chronic pulmonary disease, hemoptysis, cholesterol and IL-2R were independent predictors for death. Interpretation: Liver injury is common in COVID-19 patients, and male patients are at higher risk to have liver injury. Patients with liver injury can be severer and have a higher incidence of disease progression than those without. Funding: The present study was not supported by any funding.Declaration of Interests: All the authors declare no conflicts of interests.Ethics Approval Statement: The study protocol is approved by the Institutional Ethics Committee of Peking University First Hospital and all the methods were carried out in accordance with the approved guidelines of the committee and with the Helsinki Declaration. Informed consent is waived.

Study on β-Chitosan against the binding of SARS-CoV-2S-RBD/ACE2 (preprint)

It has been known that SARS-CoV-2 which is considered similar to SARS-CoV invades human respiratory epithelial cells through interaction with the human angiotensin converting enzyme II (ACE2). In this work, SARS-CoV-2S-RBD and its cell receptor ACE2 were used to investigate the blocking effect and mechanism of {beta}-chitosan to the binding of them. Besides, inhibitory effect of {beta}-chitosan on inflammation induced by SARS-CoV-2S-RBD was also studied. Firstly, Native-PAGE results showed that {beta}-chitosan could bind with ACE2 or SARS-CoV-2S-RBD and the conjugate of {beta}-chitosan and ACE2 could no longer bind with SARS-CoV-2S-RBD. HPLC analyses suggested that was found the conjugate of {beta}-chitosan and SARS-CoV-2S-RBD displayed high binding affinity under the condition of high pressure (40 MPa) compared with that of ACE2 and SARS-CoV-2S-RBD. Furthermore, immunofluorescence detections on Vero E6 cells and hACE2 mice showed that {beta}-chitosan had a significant prevention and treatment effect on SARS-CoV-2S-RBD binding. Meanwhile, SARS-CoV-2S-RBD binding could activate the inflammation signaling pathways of cells and mice, however, {beta}-chitosan could dramatically suppress the inflammations activated by SARS-CoV-2S-RBD. Subsequently, Western blot analyses revealed that the expression levels of ACE2 in experimental groups treated with {beta}-chitosan significantly reduced. However, after the intervention of ADAM17 inhibitor (TAPI), the decreased ACE2 expressions affected by {beta}-chitosan up-regulated correspondingly. The results indicated that {beta}-chitosan has a similar antibody function, which can neutralize SARS-CoV-2S-RBD and effectively block the binding of SARS-CoV-2S-RBD with ACE2. ADAM17 activated by {beta}-chitosan can enhance the cleavage of ACE2 extracellular domain with a catalytic activity of Ang II degradation, and then the extracellular region was released into the extracellular environment. So, {beta}-chitosan could prevent the binding, internalization and degradation of ACE2 with SARS-CoV-2S-RBD and inhibit the activation of inflammatory signaling pathways at the same time. This work provides a valuable reference for the prevention and control of SARS-CoV-2 by {beta}-chitosan.

A Survey of Characteristics and Potential Contribution of Registered Studies for 2019 novel coronavirus disease (COVID-19) (preprint)

Background The World Health Organization characterized the 2019 novel coronavirus disease (COVID-19) as a pandemic on March 11. Many clinical trials on COVID-19 have been registered, and we aim to review the characteristics of the trials and provide guidance for future trials to avoid duplicated effort.Methods All the studies on COVID-19 registered before Mar 3, 2020 on eight registry platforms worldwide were searched and the data of design, participants, interventions, and outcomes were extracted and analyzed. The most promising trials were screened based on study design, rationale, and resource availability.Results 393 studies registered were identified until Mar 3 2020 and 380 (96.7%) studies were from mainland China, while 3 in Japan, 3 in France, 2 in the US, and 3 were international collaborative studies. 363 studies (92.4%) recruited participants from hospitals and 266 studies (67.7%) aimed at therapeutic effect, others were for prevention, diagnosis, prognosis, etc. 202 studies (51.4%) were randomized controlled trials (RCTs). The average sample size was 1061 and ranged from 8 to 150,000 per study. 177 out of 266 therapeutic studies (66.5% ) tested Western medicines including antiviral drugs (17.7%), stem cell and cord blood therapy (10.2%), chloroquine and derivatives (8.3%), 16 (6.0%) on Chinese medicines, and 73 (27.4%) on integrated therapy of Western and Chinese medicines. 14 Chinese medicines had its clear rationale for evaluation of therapeutic effects. 31 studies among 266 therapeutic studies (11.7%) used mortality as primary outcome, while the most designed secondary outcomes were symptoms and signs (47.0%). 106 studies (27.0%) were funded by the government, and 268 (68.2%) demonstrated ethical approval. 45.5% studies (179 out of 266) had not started recruiting till Mar 3. Eight RCTs were evaluated as the most promising trials.Conclusions Majority of the studies focused on assessing therapeutics for COVID-19 but inappropriate outcome setting, delayed recruitment and insufficient numbers of new cases in China implied many studies may fail to complete. Strategies and protocols of the studies with robust and rapid data sharing from international collaboration are warranted for emergency public health events, helping to accelerate priority setting for timely evidence-based decision-making.

Sex Differences in Severity and Mortality Among Patients With COVID-19: Evidence from Pooled Literature Analysis and Insights from Integrated Bioinformatic Analysis (preprint)

Objective: To conduct a meta-analysis of current studies that examined sex differences in severity and mortality in patients with COVID-19, and identify potential mechanisms underpinning these differences. Methods: We performed a systematic review to collate data from observational studies examining associations of sex differences with clinical outcomes of COVID-19. PubMed, Web of Science and four preprint servers were searched for relevant studies. Data were extracted and analyzed using meta-analysis where possible, with summary data presented otherwise. Publicly available bulk RNA sequencing (RNA-seq), single-cell RNA sequencing (scRNA-seq), and chromatin immunoprecipitation sequencing (ChIP-seq) data were analyzed to explore the potential mechanisms underlying the observed association. Results: 39 studies met inclusion criteria, representing 77932 patients, of which 41510 (53.3%) were males. Men were at a markedly increased risk of developing severe cases compared with women. Furthermore, the pooled odds ratio (OR) of mortality for male group compared with the female group indicated significant higher mortality rate for male. Data from scRNA-seq suggest that men have a higher amount of ACE2-expressing pulmonary alveolar type II cells than women. Sex-based immunological differences exist. The expression of androgen receptor (AR) is positively correlated with ACE2, and there is evidence that AR may directly regulate the expression of ACE2. Conclusions: This meta-analysis detected an increased severity and mortality rate in the male populations with COVID-19, which might be attributable to the sex-based differences in cellular compositions and immunological microenvironments of the lung. The host cell receptor ACE2 is likely regulated by AR signaling pathway, which is identified as a potential target for prevention and treatment of SARS-Cov-2 infections in men.