Exacerbated innate host response to SARS-CoV in aged non-human primates. PLoS Pathog. 2010;6:e1000756. [PMID: 20140198 PMCID: PMC2816697 DOI: 10.1371/journal.ppat.1000756]

Animal Models for Human-Pathogenic Coronavirus and Animal Coronavirus Research

Coronavirus epidemics have posed a serious threat to both human and animal health. To combat emerging infectious diseases caused by coronaviruses, various animal infection models have been developed and applied in research, including non-human primate models, ferret models, hamster models, mouse models, and others. Moreover, new approaches have been utilized to develop animal models that are more susceptible to infection. These approaches include using viral delivery methods to induce the expression of viral receptors in mouse tissues and employing gene-editing techniques to create genetically modified mice. This has led to the successful establishment of infection models for multiple coronaviruses, significantly advancing related research. In contrast, livestock and pets that can be infected by animal coronaviruses provide valuable insights when used as infection models, enabling the collection of accurate clinical data through the analysis of post-infection pathological features. However, despite the potential insights, there is a paucity of research data pertaining to these infection models. In this review, we provide a detailed overview of recent progress in the development of animal models for coronaviruses that cause diseases in both humans and animals and suggest ways in which animal models can be adapted to further enhance their value in research.

Machine learning based predictive modeling and risk factors for prolonged SARS-CoV-2 shedding

BACKGROUND

The global outbreak of the coronavirus disease 2019 (COVID-19) has been enormously damaging, in which prolonged shedding of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, previously 2019-nCoV) infection is a challenge in the prevention and treatment of COVID-19. However, there is still incomplete research on the risk factors that affect delayed shedding of SARS-CoV-2.

METHODS

In a retrospective analysis of 56,878 hospitalized patients in the Fangcang Shelter Hospital (National Convention and Exhibition Center) in Shanghai, China, we compared patients with the duration of SARS-CoV-2 viral shedding > 12 days with those days < 12 days. The results of real-time polymerase chain reaction (RT-PCR) tests determined the duration of viral shedding from the first day of SARS-CoV-2 positivity to the day of SARS-CoV-2 negativity. The extreme gradient boosting (XGBoost) machine learning method was employed to establish a prediction model for prolonged SARS-CoV-2 shedding and analyze significant risk factors. Filtering features retraining and Shapley Additive Explanations (SHAP) techniques were followed to demonstrate and further explain the risk factors for long-term SARS-CoV-2 infection.

RESULTS

We conducted an assessment of ten different features, including vaccination, hypertension, diabetes, admission cycle threshold (Ct) value, cardio-cerebrovascular disease, gender, age, occupation, symptom, and family accompaniment, to determine their impact on the prolonged SARS-CoV-2 shedding. This study involved a large cohort of 56,878 hospitalized patients, and we leveraged the XGBoost algorithm to establish a predictive model based on these features. Upon analysis, six of these ten features were significantly associated with the prolonged SARS-CoV-2 shedding, as determined by both the importance order of the model and our results obtained through model reconstruction. Specifically, vaccination, hypertension, admission Ct value, gender, age, and family accompaniment were identified as the key features associated with prolonged viral shedding.

CONCLUSIONS

We developed a predictive model and identified six risk factors associated with prolonged SARS-CoV-2 viral shedding. Our study contributes to identifying and screening individuals with potential long-term SARS-CoV-2 infections. Moreover, our research also provides a reference for future preventive control, optimizing medical resource allocation and guiding epidemiological prevention, and guidelines for personal protection against SARS-CoV-2.

Predictors for COVID-19-Specific and Non-COVID-19-Specific Deaths: A Cohort Study in Taiwan

Predictors for coronavirus disease 2019 (COVID-19)-specific and non-COVID-19-specific deaths have not been extensively studied. This cohort study in Taiwan investigated predictors for COVID-19-specific and non-COVID-19-specific deaths among hospitalized patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. From January to July 2022, 2196 COVID-19 patients at Taipei City Hospital were consecutively recruited in this cohort study. Among the 175 deceased COVID-19 patients, 147 (84.0%) and 28 (16.0%) had COVID-19-specific and non-COVID-19-specific deaths, respectively. After controlling for other covariates, multinomial logistic regressions showed that age ≥ 65 was significantly associated with higher risks for both COVID-19-specific, adjusted odds ratio (AOR) = 6.21; and non-COVID-19-specific deaths (AOR = 6.06). Fully vaccinated individuals (AOR = 0.50) and Paxlovid recipients (AOR = 0.45) had lower COVID-19-specific death risks, while comorbid cancer or end-stage renal disease patients faced higher risks of non-COVID-19-specific deaths. Our study findings suggest that vaccination and Paxlovid treatment are crucial for reducing SARS-CoV-2-specific mortalities, while comorbid patients need careful monitoring to reduce non-COVID-19-specific deaths.

Eicosanoids Signals in SARS-CoV-2 Infection: A Foe or Friend

SARS-CoV-2 mediated infection instigated a scary pandemic state since 2019. They created havoc comprising death, imbalanced social structures, and a wrecked global economy. During infection, the inflammation and associated cytokine storm generate a critical pathological situation in the human body, especially in the lungs. By the passage of time of infection, inflammatory disorders, and multiple organ damage happen which might lead to death, if not treated properly. Until now, many pathological parameters have been used to understand the progress of the severity of COVID-19 but with limited success. Bioactive lipid mediators have the potential of initiating and resolving inflammation in any disease. The connection between lipid storm and inflammatory states of SARS-CoV-2 infection has surfaced and got importance to understand and mitigate the pathological states of COVID-19. As the role of eicosanoids in COVID-19 infection is not well defined, available information regarding this issue has been accumulated to address the possible network of eicosanoids related to the initiation of inflammation, promotion of cytokine storm, and resolution of inflammation, and highlight possible strategies for treatment and drug discovery related to SARS-CoV-2 infection in this study. Understanding the involvement of eicosanoids in exploration of cellular events provoked by SARS-CoV-2 infection has been summarized as an important factor to deescalate any upcoming catastrophe imposed by the lethal variants of this micro-monster. Additionally, this study also recognized the eicosanoid based drug discovery, treatment, and strategies for managing the severity of SARS-COV-2 infection.

Predictors for cause-specific and timing of deaths in patients with COVID-19: a cohort study in Taiwan

BACKGROUND

This cohort study determines the predictors for cause-specific and timing of deaths in patients with COVID-19 in Taiwan.

METHODS

Patients with laboratory-confirmed COVID-19 admitted to Taipei City Hospital from January 1 to July 31, 2022, were recruited in this cohort. All patients were followed up until death, discharge from the hospital, or August 31, 2022. Early deaths within the first 2 weeks were recorded, and the cause of death was confirmed by the death certificate database of Taiwan. Predictors of cause-specific and timing of deaths of patients with COVID-19 were determined using multinomial Cox proportional hazards regression analysis.

RESULTS

Of the 195 (8.0%) patients who died during hospitalization, 147 (84.0%) had COVID-19-specific deaths. Moreover, 54.9% of the deceased patients had early death. After controlling for other covariates, patients aged ≥ 65 years had a higher risk of COVID-19-specific, non-COVID-19-specific, early, and late deaths [adjusted hazards ratio (AHR): 3.85, 6.45, 3.33, and 6.57; 95% confidence interval (CI): 1.91-7.78, 1.17-35.68, 1.51-7.36, and 2.18-19.76, respectively]. Fully vaccinated patients had a lower risk of COVID-19-specific (AHR: 0.68; 95% CI: 0.47-0.98) and early deaths (AHR: 0.54; 95% CI: 0.35-0.84), whereas comorbid patients with chronic obstructive pulmonary disease had a higher risk of non-COVID-19-specific deaths (AHR: 5.43; 95% CI: 1.73-17.03).

CONCLUSIONS

This study suggests that prioritizing COVID-19 vaccination and carefully monitoring comorbid patients during hospitalization can reduce the risk of COVID-19-specific and early deaths and non-COVID-19-specific mortalities, respectively.

A prospective cohort-based artificial intelligence evaluation system for the protective efficacy and immune response of SARS-CoV-2 inactivated vaccines

BACKGROUND

Novel coronaviruses constitute a significant health threat, prompting the adoption of vaccination as the primary preventive measure. However, current evaluations of immune response and vaccine efficacy are deemed inadequate.

OBJECTIVES

The study sought to explore the evolving dynamics of immune response at various vaccination time points and during breakthrough infections. It aimed to elucidate the synergistic effects of epidemiological factors, humoral immunity, and cellular immunity. Additionally, regression curves were used to determine the correlation between the protective efficacy of the vaccine and the stimulated immune response.

METHODS

Employing LASSO for high-dimensional data analysis, the study utilised four machine learning algorithms-logistical regression, random forest, LGBM classifier, and AdaBoost classifier-to comprehensively assess the immune response following booster vaccination.

RESULTS

Neutralising antibody levels exhibited a rapid surge post-booster, escalating to 102.38 AU/mL at one week and peaking at 298.02 AU/mL at two weeks. Influential factors such as sex, age, disease history, and smoking status significantly impacted post-booster antibody levels. The study further constructed regression curves for neutralising antibodies, non-switched memory B cells, CD4+T cells, and CD8+T cells using LASSO combined with the random forest algorithm.

CONCLUSION

The establishment of an artificial intelligence evaluation system emerges as pivotal for predicting breakthrough infection prognosis after the COVID-19 booster vaccination. This research underscores the intricate interplay between various components of immunity and external factors, elucidating key insights to enhance vaccine effectiveness. 3D modelling discerned distinctive interactions between humoral and cellular immunity within prognostic groups (Class 0-2). This underscores the critical role of the synergistic effect of humoral immunity, cellular immunity, and epidemiological factors in determining the protective efficacy of COVID-19 vaccines post-booster administration.

Development and validation of a nomogram for predicting in-hospital survival rates of patients with COVID-19

Objective

Our aim was to develop and validate a nomogram for predicting the in-hospital 14-day (14 d) and 28-day (28 d) survival rates of patients with coronavirus disease 2019 (COVID-19).

Methods

Clinical data of patients with COVID-19 admitted to the Renmin Hospital of Wuhan University from December 2022 to February 2023 and the north campus of Shanghai Ninth People's Hospital from April 2022 to June 2022 were collected. A total of 408 patients from Renmin Hospital of Wuhan University were selected as the training cohort, and 151 patients from Shanghai Ninth People's Hospital were selected as the verification cohort. Independent variables were screened using Cox regression analysis, and a nomogram was constructed using R software. The prediction accuracy of the nomogram was evaluated using the receiver operating characteristic (ROC) curve, C-index, and calibration curve. Decision curve analysis was used to evaluate the clinical application value of the model. The nomogram was externally validated using a validation cohort.

Result

In total, 559 patients with severe/critical COVID-19 were included in this study, of whom 179 (32.02 %) died. Multivariate Cox regression analysis showed that age >80 years [hazard ratio (HR) = 1.539, 95 % confidence interval (CI): 1.027-2.306, P = 0.037], history of diabetes (HR = 1.741, 95 % CI: 1.253-2.420, P = 0.001), high APACHE II score (HR = 1.083, 95 % CI: 1.042-1.126, P < 0.001), sepsis (HR = 2.387, 95 % CI: 1.707-3.338, P < 0.001), high neutrophil-to-lymphocyte ratio (NLR) (HR = 1.010, 95 % CI: 1.003-1.017, P = 0.007), and high D-dimer level (HR = 1.005, 95 % CI: 1.001-1.009, P = 0.028) were independent risk factors for 14 d and 28 d survival rates, whereas COVID-19 vaccination (HR = 0.625, 95 % CI: 0.440-0.886, P = 0.008) was a protective factor affecting prognosis. ROC curve analysis showed that the area under the curve (AUC) of the 14 d and 28 d hospital survival rates in the training cohort was 0.765 (95 % CI: 0.641-0.923) and 0.814 (95 % CI: 0.702-0.938), respectively, and the AUC of the 14 d and 28 d hospital survival rates in the verification cohort was 0.898 (95 % CI: 0.765-0.962) and 0.875 (95 % CI: 0.741-0.945), respectively. The calibration curves of 14 d and 28 d hospital survival showed that the predicted probability of the model agreed well with the actual probability. Decision curve analysis (DCA) showed that the nomogram has high clinical application value.

Conclusion

In-hospital survival rates of patients with COVID-19 were predicted using a nomogram, which will help clinicians in make appropriate clinical decisions.

Computational methods in the analysis of SARS-CoV-2 in mammals: A systematic review of the literature

SARS-CoV-2 is an enveloped RNA virus that causes severe respiratory illness in humans and animals. It infects cells by binding the Spike protein to the host's angiotensin-converting enzyme 2 (ACE2). The bat is considered the natural host of the virus, and zoonotic transmission is a significant risk and can happen when humans come into close contact with infected animals. Therefore, understanding the interconnection between human, animal, and environmental health is important to prevent and control future coronavirus outbreaks. This work aimed to systematically review the literature to identify characteristics that make mammals suitable virus transmitters and raise the main computational methods used to evaluate SARS-CoV-2 in mammals. Based on this review, it was possible to identify the main factors related to transmissions mentioned in the literature, such as the expression of ACE2 and proximity to humans, in addition to identifying the computational methods used for its study, such as Machine Learning, Molecular Modeling, Computational Simulation, between others. The findings of the work contribute to the prevention and control of future outbreaks, provide information on transmission factors, and highlight the importance of advanced computational methods in the study of infectious diseases that allow a deeper understanding of transmission patterns and can help in the development of more effective control and intervention strategies.

Plitidepsin as an Immunomodulator against Respiratory Viral Infections

Plitidepsin is a host-targeted compound known for inducing a strong anti-SARS-CoV-2 activity, as well as for having the capacity of reducing lung inflammation. Because IL-6 is one of the main cytokines involved in acute respiratory distress syndrome, the effect of plitidepsin in IL-6 secretion in different in vitro and in vivo experimental models was studied. A strong plitidepsin-mediated reduction of IL-6 was found in human monocyte-derived macrophages exposed to nonproductive SARS-CoV-2. In resiquimod (a ligand of TLR7/8)-stimulated THP1 human monocytes, plitidepsin-mediated reductions of IL-6 mRNA and IL-6 levels were also noticed. Additionally, although resiquimod-induced binding to DNA of NF-κB family members was unaffected by plitidepsin, a decrease in the regulated transcription by NF-κB (a key transcription factor involved in the inflammatory cascade) was observed. Furthermore, the phosphorylation of p65 that is required for full transcriptional NF-κB activity was significantly reduced by plitidepsin. Moreover, decreases of IL-6 levels and other proinflammatory cytokines were also seen in either SARS-CoV-2 or H1N1 influenza virus-infected mice, which were treated at low enough plitidepsin doses to not induce antiviral effects. In summary, plitidepsin is a promising therapeutic agent for the treatment of viral infections, not only because of its host-targeted antiviral effect, but also for its immunomodulatory effect, both of which were evidenced in vitro and in vivo by the decrease of proinflammatory cytokines.

Diverging patterns in innate immunity against respiratory viruses during a lifetime: lessons from the young and the old

Respiratory viral infections frequently lead to severe respiratory disease, particularly in vulnerable populations such as young children, individuals with chronic lung conditions and older adults, resulting in hospitalisation and, in some cases, fatalities. The innate immune system plays a crucial role in monitoring for, and initiating responses to, viruses, maintaining a state of preparedness through the constant expression of antimicrobial defence molecules. Throughout the course of infection, innate immunity remains actively involved, contributing to viral clearance and damage control, with pivotal contributions from airway epithelial cells and resident and newly recruited immune cells. In instances where viral infections persist or are not effectively eliminated, innate immune components prominently contribute to the resulting pathophysiological consequences. Even though both young children and older adults are susceptible to severe respiratory disease caused by various respiratory viruses, the underlying mechanisms may differ significantly. Children face the challenge of developing and maturing their immunity, while older adults contend with issues such as immune senescence and inflammaging. This review aims to compare the innate immune responses in respiratory viral infections across both age groups, identifying common central hubs that could serve as promising targets for innovative therapeutic and preventive strategies, despite the apparent differences in underlying mechanisms.

The Role of the Nuclear Factor-Kappa B (NF-κB) Pathway in SARS-CoV-2 Infection

COVID-19 is a global health threat caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and is associated with a significant increase in morbidity and mortality. The present review discusses nuclear factor-kappa B (NF-κB) activation and its potential therapeutical role in treating COVID-19. COVID-19 pathogenesis, the major NF-κB pathways, and the involvement of NF-κB in SARS-CoV-2 have been detailed. Specifically, NF-κB activation and its impact on managing COVID-19 has been discussed. As a central player in the immune and inflammatory responses, modulating NF-κB activation could offer a strategic avenue for managing SARS-CoV-2 infection. Understanding the NF-κB pathway's role could aid in developing treatments against SARS-CoV-2. Further investigations into the intricacies of NF-κB activation are required to reveal effective therapeutic strategies for managing and combating the SARS-CoV-2 infection and COVID-19.

Comparative Pathogenesis of Severe Acute Respiratory Syndrome Coronaviruses

Over the last two decades the world has witnessed the global spread of two genetically related highly pathogenic coronaviruses, severe acute respiratory syndrome coronavirus (SARS-CoV) and SARS-CoV-2. However, the impact of these outbreaks differed significantly with respect to the hospitalizations and fatalities seen worldwide. While many studies have been performed recently on SARS-CoV-2, a comparative pathogenesis analysis with SARS-CoV may further provide critical insights into the mechanisms of disease that drive coronavirus-induced respiratory disease. In this review, we comprehensively describe clinical and experimental observations related to transmission and pathogenesis of SARS-CoV-2 in comparison with SARS-CoV, focusing on human, animal, and in vitro studies. By deciphering the similarities and disparities of SARS-CoV and SARS-CoV-2, in terms of transmission and pathogenesis mechanisms, we offer insights into the divergent characteristics of these two viruses. This information may also be relevant to assessing potential novel introductions of genetically related highly pathogenic coronaviruses.

Paving new roads toward the advancement of broad-spectrum antiviral agents

Broad-spectrum antivirals (BSAs) have the advantageous property of being effective against a wide range of viruses with a single drug, offering a promising therapeutic solution for the largely unmet need in treating both existing and emerging viral infections. In this review, we summarize the current strategies for the development of novel BSAs, focusing on either targeting the commonalities during the replication of multiple viruses or the systemic immunity of humans. In comparison to BSAs that target viral replication, these immuno-modulatory agents possess an expanded spectrum of antiviral activity. However, antiviral immunity is a double-edged sword, and maintaining immune homeostasis ultimately dictates the health status of hosts during viral infections. Therefore, establishing an ideal goal for immuno-modulation in antiviral interventions is crucial. Herein we propose a bionic approach for immuno-modulation inspired by mimicking bats, which possess a more robust immune system for combating viral invasions, compared to humans. In addition, we discuss an empirical approach to treat diverse viral infections using traditional Chinese medicines (TCMs), mainly through bidirectional immuno-modulation to restore the disrupted homeostasis. Advancing our understanding of both the immune system of bats and the mechanisms underlying antiviral TCMs will significantly contribute to the future development of novel BSAs.

Association of New-Onset Atrial Fibrillation With All-Cause Mortality in COVID-19 Patients

Background The COVID-19 pandemic has brought about unprecedented global health challenges, with its impact extending beyond respiratory manifestations to encompass cardiovascular complications, including arrhythmias. Dysrhythmias in COVID-19 are multifactorial, ranging from direct myocardial insult due to the cytokine storm to metabolic derangements. Objective In this study, we aim to examine the incidence of new-onset atrial fibrillation and to study its association with all-cause mortality of COVID-19. Methods A cross-sectional study was conducted at Cabell Huntington Hospital, West Virginia, utilizing electronic medical records of COVID-19 patients from 2020 to 2021. Inclusion criteria comprised patients aged >18 years with COVID-19 diagnosis and cardiac arrhythmias during hospitalization. Logistic regression analysis was employed to examine the relationship between demographic and clinical variables and in-hospital mortality. Results Of the 264 eligible patients, those aged >66 years had lower odds of in-hospital mortality (p < 0.001), while gender, ejection fraction, and diabetes mellitus did not significantly predict mortality. Atrial fibrillation (p = 0.011) and heart failure (p = 0.030) were associated with increased odds of mortality, while hypertension showed no significant predictive power (p = 0.791). Conclusion This study highlights the significance of atrial fibrillation and heart failure as predictors of in-hospital mortality in COVID-19 patients. Our findings underscore the importance of recognizing and managing arrhythmias in COVID-19 and call for further research on the mechanisms and long-term effects of these cardiac complications in the context of the pandemic. These insights can guide clinical practice and interventions to optimize patient outcomes.

Biochemical Analysis of Ferritin and D-dimer in COVID-19 Survivors and Non-survivors

Background COVID-19 is a major cause of illness and mortality. The management of COVID-19-related illnesses might change if variables connected to their severity and the requirement for ICU admission could be found. The severity of COVID-19 might be efficiently predicted with several laboratory measures, such as ferritin levels and D-dimer analysis. Objectives This study aimed to evaluate the association between serum D-dimer and ferritin levels and their effects on mortality in patients with COVID-19. Methods This retrospective observational study included all patients with positive real-time polymerase chain reaction (RT-PCR) results for COVID-19 who were hospitalized in the Ministry of Health South Al-Qunfudah General Hospital between March and September 30, 2020. Their laboratory parameters, serum D-dimer, and ferritin levels were evaluated. IBM SPSS Statistics for Windows, Version 26.0 (released 2019; IBM Corp., Armonk, New York, United States) was used to analyze the data. Results A total of 318 COVID-19 patients were analyzed; 56.9% (n=181) were male and 43.1% (n=137) were female. Of these, 78.6% (n=250) survived, including 58% of men and 42% of women. The mean D-dimer was 2.1 mcg/mL (SD=3.16) and the mean ferritin was 698.59 ng/mL (SD=603.11). Non-recovered patients were substantially older (66.16 years old) and had higher D-dimer (5.46) mcg/mL and ferritin levels (992.96) ng/mL. Intubation length and gender did not affect survival. Of the non-survivors, 95.6% (n=239) were admitted to the ICU, and 50% (n=34) required mechanical ventilation. Conclusions COVID-19 infection mortality dramatically increased with older age and increased mean ferritin and plasma D-dimer values, which were significantly higher in COVID-19 non-survivors than in survivors. Therefore, assessing and monitoring these laboratory markers in the early stages of the disease may have a significant impact on preventing disease progression and death.

The Impact of Serum Levels of Reactive Oxygen and Nitrogen Species on the Disease Severity of COVID-19

Elucidation of the redox pathways in severe coronavirus disease 2019 (COVID-19) might aid in the treatment and management of the disease. However, the roles of individual reactive oxygen species (ROS) and individual reactive nitrogen species (RNS) in COVID-19 severity have not been studied to date. The main objective of this research was to assess the levels of individual ROS and RNS in the sera of COVID-19 patients. The roles of individual ROS and RNS in COVID-19 severity and their usefulness as potential disease severity biomarkers were also clarified for the first time. The current case-control study enrolled 110 COVID-19-positive patients and 50 healthy controls of both genders. The serum levels of three individual RNS (nitric oxide (NO^•), nitrogen dioxide (ONO^-), and peroxynitrite (ONOO^-)) and four ROS (superoxide anion (O₂^•-), hydroxyl radical (^•OH), singlet oxygen (¹O₂), and hydrogen peroxide (H₂O₂)) were measured. All subjects underwent thorough clinical and routine laboratory evaluations. The main biochemical markers for disease severity were measured and correlated with the ROS and RNS levels, and they included tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), the neutrophil-to-lymphocyte ratio (NLR), and angiotensin-converting enzyme 2 (ACE2). The results indicated that the serum levels of individual ROS and RNS were significantly higher in COVID-19 patients than in healthy subjects. The correlations between the serum levels of ROS and RNS and the biochemical markers ranged from moderate to very strongly positive. Moreover, significantly elevated serum levels of ROS and RNS were observed in intensive care unit (ICU) patients compared with non-ICU patients. Thus, ROS and RNS concentrations in serum can be used as biomarkers to track the prognosis of COVID-19. This investigation demonstrated that oxidative and nitrative stress play a role in the etiology of COVID-19 and contribute to disease severity; thus, ROS and RNS are probable innovative targets in COVID-19 therapeutics.

Senotherapeutics: An emerging approach to the treatment of viral infectious diseases in the elderly

In the context of the global COVID-19 pandemic, the phenomenon that the elderly have higher morbidity and mortality is of great concern. Existing evidence suggests that senescence and viral infection interact with each other. Viral infection can lead to the aggravation of senescence through multiple pathways, while virus-induced senescence combined with existing senescence in the elderly aggravates the severity of viral infections and promotes excessive age-related inflammation and multiple organ damage or dysfunction, ultimately resulting in higher mortality. The underlying mechanisms may involve mitochondrial dysfunction, abnormal activation of the cGAS-STING pathway and NLRP3 inflammasome, the role of pre-activated macrophages and over-recruited immune cells, and accumulation of immune cells with trained immunity. Thus, senescence-targeted drugs were shown to have positive effects on the treatment of viral infectious diseases in the elderly, which has received great attention and extensive research. Therefore, this review focused on the relationship between senescence and viral infection, as well as the significance of senotherapeutics for the treatment of viral infectious diseases.

Dermatological Manifestations in COVID-19: A Case Study of SARS-CoV-2 Infection in a Genetic Thrombophilic Patient with Mthfr Mutation

The present case study describes the dermatological manifestations of COVID-19 in a patient with genetic thrombophilia (MTHFR–C677T mutation) and the identification of a SARS-CoV-2 variant of interest (VOI). A female patient, 47 years old, unvaccinated, with thrombophilia, was diagnosed with COVID-19. She presented with urticarial and maculopapular eruptions from the seventh day of symptoms, which progressed to multiple lesions with dark centers (D-dimer value > 1450 ng/mL). The dermatological manifestations disappeared after 30 days, corroborating the reduction in D-dimer levels. Viral genome sequencing revealed infection by the VOI Zeta (P.2). Antibody testing, performed 30 days after the onset of symptoms, detected only IgG. The virus neutralization test showed the highest neutralizing titer for a P.2 strain, validating the genotypic identification. Lesions were suggested to be due to infection in skin cells causing a direct cytopathic effect or release of pro-inflammatory cytokines triggering erythematous and urticarial eruptions. In addition, vascular complications are also proposed to be due to the MTHFR mutation and increased D-dimer values. This case report is an alert about COVID-19 in patients with pre-existing vascular diseases, especially in unvaccinated patients, by VOI.

Severe acute respiratory syndrome coronaviruses contributing to mitochondrial dysfunction: Implications for post-COVID complications

Mitochondria play a central role in oxidative phosphorylation (OXPHOS), bioenergetics linked with ATP production, fatty acids biosynthesis, calcium signaling, cell cycle regulation, apoptosis, and innate immune response. Severe acute respiratory syndrome-associated coronavirus (SARS-CoV) infection manipulates the host cellular machinery for its survival and replication in the host cell. The infectiaon causes perturbed the cellular metabolism that favours viral replication leading to mitochondrial dysfunction and chronic inflammation. By localizing to the mitochondria, SARS CoV proteins increase reactive oxygen species (ROS) levels, perturbation of Ca2+ signaling, changes in mtDNA copy number, mitochondrial membrane potential (MMP), mitochondrial mass, and induction of mitophagy. These proteins also influence the fusion and fission kinetics, size, structure, and distribution of mitochondria in the infected host cells. This results in compromised bioenergetics, altered metabolism, and innate immune signaling, and hence can be a key player in determining the outcome of SARS-CoV infection. SARS-CoV infection contributes to stress and activates apoptotic pathways. This review summarizes how mitochondrial function and dynamics are affected by SARS-CoV and how the mitochondria-SARS-CoV interaction benefits viral survival and growth by evading innate host immunity. We also highlight how the SARS-CoV-mediated mitochondrial dysfunction contributes to post-COVID complications. Besides, a discussion on targeting virus-mitochondria interactions as a therapeutic strategy is presented.

Automated prediction of COVID-19 mortality outcome using clinical and laboratory data based on hierarchical feature selection and random forest classifier

Early prediction of COVID-19 mortality outcome can decrease expiration risk by alerting healthcare personnel to assure efficient resource allocation and treatment planning. This study introduces a machine learning framework for the prediction of COVID-19 mortality using demographics, vital signs, and laboratory blood tests (complete blood count (CBC), coagulation, kidney, liver, blood gas, and general). 41 features from 244 COVID-19 patients were recorded on the first day of admission. In this study, first, the features in each of the eight categories were investigated. Afterward, features that have an area under the receiver operating characteristic curve (AUC) above 0.6 and the p-value criterion from the Wilcoxon rank-sum test below 0.005 were used as selected features for further analysis. Then five feature reduction methods, Forward Feature selection, minimum Redundancy Maximum Relevance, Relieff, Linear Discriminant Analysis, and Neighborhood Component Analysis were utilized to select the best combination of features. Finally, seven classifiers frameworks, random forest (RF), support vector machine, logistic regression (LR), K nearest neighbors, Artifical neural network, bagging, and boosting were used to predict the mortality outcome of COVID-19 patients. The results revealed that the combination of features in CBC and then vital signs had the highest mortality classification parameters, respectively. Furthermore, the RF classifier with hierarchical feature selection algorithms via Forward Feature selection had the highest classification power with an accuracy of 92.08 ± 2.56. Therefore, our proposed method can be confidently used as a valuable assistant prognostic tool to sieve patients with high mortality risks.

Immune correlates of protection for SARS-CoV-2, Ebola and Nipah virus infection

Correlates of protection (CoP) are biological parameters that predict a certain level of protection against an infectious disease. Well-established correlates of protection facilitate the development and licensing of vaccines by assessing protective efficacy without the need to expose clinical trial participants to the infectious agent against which the vaccine aims to protect. Despite the fact that viruses have many features in common, correlates of protection can vary considerably amongst the same virus family and even amongst a same virus depending on the infection phase that is under consideration. Moreover, the complex interplay between the various immune cell populations that interact during infection and the high degree of genetic variation of certain pathogens, renders the identification of immune correlates of protection difficult. Some emerging and re-emerging viruses of high consequence for public health such as SARS-CoV-2, Nipah virus (NiV) and Ebola virus (EBOV) are especially challenging with regards to the identification of CoP since these pathogens have been shown to dysregulate the immune response during infection. Whereas, virus neutralising antibodies and polyfunctional T-cell responses have been shown to correlate with certain levels of protection against SARS-CoV-2, EBOV and NiV, other effector mechanisms of immunity play important roles in shaping the immune response against these pathogens, which in turn might serve as alternative correlates of protection. This review describes the different components of the adaptive and innate immune system that are activated during SARS-CoV-2, EBOV and NiV infections and that may contribute to protection and virus clearance. Overall, we highlight the immune signatures that are associated with protection against these pathogens in humans and could be used as CoP.

Serum oxidant, antioxidant, and paraoxonase levels in COVID-19 patients

Purpose: The aim of his study was to determine serum oxidant status (TOS), antioxidant status (TAS), and paraoxonase (PON1) levels and to determine their diagnostic values in patients diagnosed with COVID-19. Materials and Methods: The research was carried out on patients diagnosed with COVID-19. Within the scope of the study, a total of 87 patients with a diagnosis of COVID-19, 48 (55.1%) male and 39 (44.9%) were evaluated. Total antioxidant determination was performed using a microplate reader according to the Erel method. To calculate the Oxidative stress index (OSI), TOS and TAS levels were determined. Results: Male gender was associated with high PON1, smoking with high TOS, the presence of hypertension and Diabetes mellitus (DM) diseases with low OSI, and the presence of asthma with low PON1. High PON1 was found to be associated with shorter hospitalization duration and high TOS was associated with longer hospitalization duration. TAS and TOS levels increased significantly due to the increase in CRP, TOS levels due to the increase in neutrophil level, OSI levels due to the increase in leukocyte level, PON1 levels increased due to the increase in LDH level TAS, TOS, OSI, and PON1 cut-off values were 1.41 (AUC: 0.647), 4.56 (AUC: 0.493), 0.421 (AUC: 0.505) and 340 (AUC: 0.536), sensitivity values were 65.5, 55.2, 48.3 and 51.7; specificity values were calculated respectively as 62.1, 46.6, 34.5 and 53.4. Conclusion: Although it is seen that oxidative stress types have diagnostic value, there is a need for more comprehensive studies with larger samples on the subject.

Resistance of Field-Isolated Porcine Epidemic Diarrhea Virus to Interferon and Neutralizing Antibody

Variant porcine epidemic diarrhea virus (PEDV), belonging to the genogroup G2b, has higher pathogenicity and mortality than classical PEDV, belonging to the genogroup G1a. To understand the pathogenesis of the G2b PEDV, we examined the resistance of the G2b PEDV to interferon (IFN) and neutralizing antibodies, which are important for controlling PEDV infection. We found that the G2b PEDV showed higher resistance to IFN than G1a PEDV. The G1a PEDV could replicate in IFN-deficient Vero cells, but not in IFN-releasing porcine alveolar macrophages, whereas the G2b PEDV showed similar infectivity in both types of cells. We also found that G2b PEDV was not effectively blocked by neutralizing antibodies, unlike G1a PEDV, suggesting differences in the antigenicity of the two strains. These results provide an understanding of the occurrence of variant PEDV and its pathogenesis.

Epidemiological characteristics and quarantine assessment of imported international COVID-19 cases, March to December 2020, Chengdu, China

International flights have accelerated the global spread of Coronavirus Disease 2019 (COVID-19). Determination of the optimal quarantine period for international travelers is crucial to prevent the local spread caused by imported COVID-19 cases. We performed a retrospective epidemiological study using 491 imported COVID-19 cases in Chengdu, China, to describe the characteristic of the cases and estimate the time from arrival to confirmation for international travelers using nonparametric survival methods. Among the 491 imported COVID-19 cases, 194 (39.5%) were asymptomatic infections. The mean age was 35.6 years (SD = 12.1 years) and 83.3% were men. The majority (74.1%) were screened positive for SARS-CoV-2, conducted by Chengdu Customs District, the People's Republic of China. Asymptomatic cases were younger than presymptomatic or symptomatic cases (P < 0.01). The daily number of imported COVID-19 cases displayed jagged changes. 95% of COVID-19 cases were confirmed by PT-PCR within 14 days (95% CI 13-15) after arriving in Chengdu. A 14-day quarantine measure can ensure non-infection among international travelers with a 95% probability. Policymakers may consider an extension of the quarantine period to minimize the negative consequences of the COVID-19 confinement and prevent the international spread of COVID-19. Nevertheless, the government should consider the balance between COVID-19 and socioeconomic development, which may cause more serious social and health crises.

Disengaging the COVID-19 Clutch as a Discerning Eye Over the Inflammatory Circuit During SARS-CoV-2 Infection

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes the cytokine release syndrome (CRS) and leads to multiorgan dysfunction. Mitochondrial dynamics are fundamental to protect against environmental insults, but they are highly susceptible to viral infections. Defective mitochondria are potential sources of reactive oxygen species (ROS). Infection with SARS-CoV-2 damages mitochondria, alters autophagy, reduces nitric oxide (NO), and increases both nicotinamide adenine dinucleotide phosphate oxidases (NOX) and ROS. Patients with coronavirus disease 2019 (COVID-19) exhibited activated toll-like receptors (TLRs) and the Nucleotide-binding and oligomerization domain (NOD-), leucine-rich repeat (LRR-), pyrin domain-containing protein 3 (NLRP3) inflammasome. The activation of TLRs and NLRP3 by SARS-CoV-2 induces interleukin 6 (IL-6), IL-1β, IL-18, and lactate dehydrogenase (LDH). Herein, we outline the inflammatory circuit of COVID-19 and what occurs behind the scene, the interplay of NOX/ROS and their role in hypoxia and thrombosis, and the important role of ROS scavengers to reduce COVID-19-related inflammation.

Circulating multimeric immune complexes contribute to immunopathology in COVID-19

A dysregulated immune response with high levels of SARS-CoV-2 specific IgG antibodies characterizes patients with severe or critical COVID-19. Although a robust IgG response is considered to be protective, excessive triggering of activating Fc-gamma-receptors (FcγRs) could be detrimental and cause immunopathology. Here, we document excessive FcγRIIIA/CD16A activation in patients developing severe or critical COVID-19 but not in those with mild disease. We identify two independent ligands mediating extreme FcγRIIIA/CD16A activation. Soluble circulating IgG immune complexes (sICs) are detected in about 80% of patients with severe and critical COVID-19 at levels comparable to active systemic lupus erythematosus (SLE) disease. FcγRIIIA/CD16A activation is further enhanced by afucosylation of SARS-CoV-2 specific IgG. Utilizing cell-based reporter systems we provide evidence that sICs can be formed prior to a specific humoral response against SARS-CoV-2. Our data suggest a cycle of immunopathology driven by an early formation of sICs in predisposed patients. These findings suggest a reason for the seemingly paradoxical findings of high antiviral IgG responses and systemic immune dysregulation in severe COVID-19. The involvement of circulating sICs in the promotion of immunopathology in predisposed patients opens new possibilities for intervention strategies to mitigate critical COVID-19 progression.

During viral infections high levels of antibodies can form soluble immune complexes (sICs) with antigen and trigger Fcγ receptors (FcγR) leading to increased immunopathology. Here the authors measure FcγRs activation by sICs and consider how these may lead to excessive immunopathology during severe SARS-CoV-2 infection.

Factors Modulating COVID-19: A Mechanistic Understanding Based on the Adverse Outcome Pathway Framework

Addressing factors modulating COVID-19 is crucial since abundant clinical evidence shows that outcomes are markedly heterogeneous between patients. This requires identifying the factors and understanding how they mechanistically influence COVID-19. Here, we describe how eleven selected factors (age, sex, genetic factors, lipid disorders, heart failure, gut dysbiosis, diet, vitamin D deficiency, air pollution and exposure to chemicals) influence COVID-19 by applying the Adverse Outcome Pathway (AOP), which is well-established in regulatory toxicology. This framework aims to model the sequence of events leading to an adverse health outcome. Several linear AOPs depicting pathways from the binding of the virus to ACE2 up to clinical outcomes observed in COVID-19 have been developed and integrated into a network offering a unique overview of the mechanisms underlying the disease. As SARS-CoV-2 infectibility and ACE2 activity are the major starting points and inflammatory response is central in the development of COVID-19, we evaluated how those eleven intrinsic and extrinsic factors modulate those processes impacting clinical outcomes. Applying this AOP-aligned approach enables the identification of current knowledge gaps orientating for further research and allows to propose biomarkers to identify of high-risk patients. This approach also facilitates expertise synergy from different disciplines to address public health issues.

Systemic inflammation indices predict mortality in patients with COVID-19

Aim: In recent years, inflammation-based indices obtained from hematologic parameters have been shown to have prognostic value in various inflammatory diseases and cancer types. In this study, we aimed to investigate whether inflammation indices could be used to predict mortality in patients with COVID-19. Material and Method: A total of 295 patients with a proven diagnosis of COVID-19 who were followed up in the intensive care unit were included in this retrospective, cross-sectional study. The patients were divided into two groups, survivors and non-survivors. Results: D-dimer (HR:1.001, 95% CI:1-1.001) and troponin (HR: 1.001 95% CI: 1-1.001) levels of non-survivors were significantly higher in univariate analyses (p&lt;0.05). Procalcitonin levels of whom were found to be high in univariate (HR: 1.018 95% CI: 1.003 – 1.034) and multivariate (HR:1.02 95% CI: 1.004-1.037) analyses (p&lt;0.05). There was no significant difference between the groups in terms of median values of PLR, SIRI, and AISI indices (p&gt;0.05). The median NLR value of the survivors was 7.45, while it was 11.39 in the non-survivors, and this difference was statistically significant (p&lt;0.001). The median value of the SII index of the non-survivors was found as 2421.02, which was significantly higher than the survivors (p&lt;0.001). The value of NLR and SII indices in predicting mortality in COVID-19 was evaluated using ROC analysis (NLR: AUC=0.644, 95%CI: 0.581-0.708, p&lt;0.001; SII: AUC=0.584, 95%CI: 0.517-0.651, p=0.017). When the cut-off value for NLR was accepted as 9.574, the sensitivity was 59.3% and the specificity was 67% in predicting mortality. When the cut-off value for SII was accepted as 2285,846, it was found that it could predict mortality with a sensitivity of 52.38% and specificity of 66.04%. Conclusion: SII and NLR indices can predict mortality in patients with COVID-19 followed up in the intensive care unit.

The hormetic and hermetic role of IL-6

Interleukin-6 is a pleiotropic cytokine regulating different tissues and organs in diverse and sometimes discrepant ways. The dual and sometime hermetic nature of IL-6 action has been highlighted in several contexts and can be explained by the concept of hormesis, in which beneficial or toxic effects can be induced by the same molecule depending on the intensity, persistence, and nature of the stimulation. According with hormesis, a low and/or controlled IL-6 release is associated with anti-inflammatory, antioxidant, and pro-myogenic actions, whereas increased systemic levels of IL-6 can induce pro-inflammatory, pro-oxidant and pro-fibrotic responses. However, many aspects regarding the multifaceted action of IL-6 and the complex nature of its signal transduction remains to be fully elucidated. In this review we collect mechanistic insight into the molecular networks contributing to normal or pathologic changes during advancing age and in chronic diseases. We point out the involvement of IL-6 deregulation in aging-related diseases, dissecting the hormetic action of this key mediator in different tissues, with a special focus on skeletal muscle. Since IL-6 can act as an enhancer of detrimental factor associated with both aging and pathologic conditions, such as chronic inflammation and oxidative stress, this cytokine could represent a "Gerokine", a determinant of the switch from physiologic aging to age-related diseases.

Animal models for studying coronavirus infections and developing antiviral agents and vaccines

In addition to severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV), SARS-CoV-2 has become the third deadly coronavirus that infects humans and causes the new coronavirus disease (COVID-19). COVID-19 has already caused more than six million deaths worldwide and it is likely the biggest pandemic of this century faced by mankind. Although many studies on SARS-CoV-2 have been conducted, a detailed understanding of SARS-CoV-2 and COVID-19 is still lacking. Animal models are indispensable for studying its pathogenesis and developing vaccines and antivirals. In this review, we analyze animal models of coronavirus infections and explore their applications on antivirals and vaccines.

Nonhuman primate models for evaluation of SARS-CoV-2 vaccines

INTRODUCTION

Evaluation of immunogenicity and efficacy in animal models provide critical data in vaccine development. Nonhuman primates (NHPs) have been used extensively in the evaluation of SARS-CoV-2 vaccines.

AREAS COVERED

A critical synthesis of SARS-CoV-2 vaccine development with a focus on challenge studies in NHPs is provided. The benefits and drawbacks of the NHP models are discussed. The citations were selected by the authors based on PubMed searches of the literature, summaries from national public health bodies, and press-release information provided by vaccine developers.

EXPERT OPINION

We identify several aspects of NHP models that limit their usefulness for vaccine-challenge studies and numerous variables that constrain comparisons across vaccine platforms. We propose that studies conducted in NHPs for vaccine development should use a standardized protocol and, where possible, be substituted with smaller animal models. This will ensure continued rapid progression of vaccines to clinical trials without compromising assessments of safety or efficacy.

Oxidative stress and decreased Nrf2 level in pediatric patients with COVID-19

The aim of this study was to investigate the change in nuclear factor erythroid 2-related factor (Nrf2), which plays a critical role in cytoprotection against oxidative stress, in pediatric patients with coronavirus disease 2019 (COVID-19) infection positivity, and to evaluate the relationship between Nrf2 and oxidative balance. The study included 40 children with confirmed COVID-19 infection and 35 healthy children. The groups were compared in respect of Nrf2, total oxidant status (TOS), total antioxidant status (TAS), and oxidative stress index (OSI), in addition to clinical findings of fever, cough, shortness of breath, contact history, and demographic data of age and gender. The mean Nrf2 values and TAS levels were determined to be statistically significantly low (p < 0.001) and the TOS level and OSI were statistically significantly high in the children with COVID-19 compared to the control group. A significant positive correlation was determined between Nrf2 and TAS (p < 0.01); as the Nrf2 value increased, so the TAS value increased. A significant negative correlation was determined between Nrf2 and TOS and OSI (p < 0.01); as the Nrf2 value increased, there was determined to be a significant decrease in the TOS and OSI values. COVID-19 infection in pediatric patients causes a decrease in the Nrf2 level. By causing a decrease in the TAS level and an increase in the TOS and OSI levels, the decrease in Nrf2 may explain the tissue damage which can be caused by COVID-19.

SARS-CoV-2 pathogenesis

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a devastating pandemic. Although most people infected with SARS-CoV-2 develop a mild to moderate disease with virus replication restricted mainly to the upper airways, some progress to having a life-threatening pneumonia. In this Review, we explore recent clinical and experimental advances regarding SARS-CoV-2 pathophysiology and discuss potential mechanisms behind SARS-CoV-2-associated acute respiratory distress syndrome (ARDS), specifically focusing on new insights obtained using novel technologies such as single-cell omics, organoid infection models and CRISPR screens. We describe how SARS-CoV-2 may infect the lower respiratory tract and cause alveolar damage as a result of dysfunctional immune responses. We discuss how this may lead to the induction of a 'leaky state' of both the epithelium and the endothelium, promoting inflammation and coagulation, while an influx of immune cells leads to overexuberant inflammatory responses and immunopathology. Finally, we highlight how these findings may aid the development of new therapeutic interventions against COVID-19.

A Broad Antiviral Strategy: Inhibitors of Human DHODH Pave the Way for Host-Targeting Antivirals against Emerging and Re-Emerging Viruses

New strategies to rapidly develop broad-spectrum antiviral therapies are urgently required for emerging and re-emerging viruses. Host-targeting antivirals (HTAs) that target the universal host factors necessary for viral replication are the most promising approach, with broad-spectrum, foresighted function, and low resistance. We and others recently identified that host dihydroorotate dehydrogenase (DHODH) is one of the universal host factors essential for the replication of many acute-infectious viruses. DHODH is a rate-limiting enzyme catalyzing the fourth step in de novo pyrimidine synthesis. Therefore, it has also been developed as a therapeutic target for many diseases relying on cellular pyrimidine resources, such as cancers, autoimmune diseases, and viral or bacterial infections. Significantly, the successful use of DHODH inhibitors (DHODHi) against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection further supports the application prospects. This review focuses on the advantages of HTAs and the antiviral effects of DHODHi with clinical applications. The multiple functions of DHODHi in inhibiting viral replication, stimulating ISGs expression, and suppressing cytokine storms make DHODHi a potent strategy against viral infection.

Systemic arterial hypertension as a risk factor for the severe form of covid-19: scoping review

OBJECTIVE

Identify whether systemic arterial hypertension is a risk factor for the severe form of covid-19.

METHODS

This is a scoping review, searches were performed on the Lilacs, PubMed, SciELO and Web of Science databases.

RESULTS

Thirteen articles were selected. The studies presented systemic arterial hypertension as the most common chronic disease in subjects diagnosed with covid-19. Hypertensive subjects were older, and men were more likely to develop severe covid-19. Hypertensive subjects without antihypertensive treatment were associated with a higher risk of mortality.

CONCLUSIONS

subjects with chronic diseases tend to have a different clinical profile. Blood pressure should be controlled in hypertensive subjects that should be continuously monitored during the covid-19 infection.

TP53 Gene Therapy as a Potential Treatment for Patients with COVID-19

SGT-53 is a novel investigational agent that comprises an immunoliposome carrying a plasmid vector driving expression of the human TP53 gene that encodes wild-type human p53. SGT-53 is currently in phase II human trials for advanced pancreatic cancer. Although p53 is best known as a tumor suppressor, its participation in both innate and adaptive immune responses is well documented. It is now clear that p53 is an important component of the host response to various viral infections. To facilitate their viral life cycles, viruses have developed a diverse repertoire of strategies for counteracting the antiviral activities of host immune system by manipulating p53-dependent pathways in host cells. Coronaviruses reduce endogenous p53 levels in the cells they infect by enhancing the degradation of p53 in proteasomes. Thus, interference with p53 function is an important component in viral pathogenesis. Transfection of cells by SGT-53 has been shown to transiently produce exogenous p53 that is active as a pleiotropic transcription factor. We herein summarize the rationale for repurposing SGT-53 as a therapy for infection by SARS-CoV-2, the pathogen responsible for the COVID-19 pandemic. Because p53 regulation was found to play a crucial role in different infection stages of a wide variety of viruses, it is rational to believe that restoring p53 function based on SGT-53 treatment may lead to beneficial therapeutic outcomes for infectious disease at large including heretofore unknown viral pathogens that may emerge in the future.

Predictors for Early and Late Death in Adult Patients with COVID-19: A Cohort Study

The timing of death in patients with coronavirus disease 2019 (COVID-19) varied by their comorbidities and severity of illness. However, few studies have determined predictors of mortality with respect to the timing of death in infectious patients. This cohort study aimed to identify the factors associated with early and late death in hospitalized COVID-19 patients. From 14 May to 31 July 2021, this study consecutively recruited laboratory-confirmed COVID-19 patients admitted to Taipei City Hospital. All patients with COVID-19 were followed up until death or discharge from the hospital or till 13 August 2021. Mortality in such patients was categorized as early death (death within the first two weeks of hospitalization) or late death (mortality later than two weeks after hospitalization), based on the timing of death. Multinomial logistic regression was used to determine the factors associated with early and late death among such patients. Of 831 recruited patients, the overall mean age was 59.3 years, and 12.2% died during hospitalization. Of the 101 deceased, 66 (65.3%) and 35 (34.7%) died early and late, respectively. After adjusting for demographics and comorbidities, independent predictors for early death included age ≥ 65 years (adjusted odds ratio (AOR) = 5.27; 95% confidence interval (CI): 2.88–9.65), heart failure (AOR = 10.32; 95% CI: 2.28–46.65), and end-stage renal disease (AOR = 11.97; 95% CI: 3.53–40.55). This study found that two thirds of COVID-19 deaths occurred within two weeks of hospitalization. It suggests that hospitalized patients with COVID-19 should be treated carefully and monitored closely for the progression of clinical conditions during treatment, particularly in older patients and in those with comorbidities.

Increased Placental Anti-Oxidant Response in Asymptomatic and Symptomatic COVID-19 Third-Trimester Pregnancies

Despite Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) -induced Oxidative Stress (OxS) being well documented in different organs, the molecular pathways underlying placental OxS in late-pregnancy women with SARS-CoV-2 infection are poorly understood. Herein, we performed an observational study to determine whether placentae of women testing positive for SARS-CoV-2 during the third trimester of pregnancy showed redox-related alterations involving Catalase (CAT) and Superoxide Dismutase (SOD) antioxidant enzymes as well as placenta morphological anomalies relative to a cohort of healthy pregnant women. Next, we evaluated if placental redox-related alterations and mitochondria pathological changes were correlated with the presence of maternal symptoms. We observed ultrastructural alterations of placental mitochondria accompanied by increased levels of oxidative stress markers Thiobarbituric Acid Reactive Substances (TBARS) and Hypoxia Inducible Factor-1 α (HIF-1α) in SARS-CoV-2 women during the third trimester of pregnancy. Importantly, we found an increase in placental CAT and SOD antioxidant enzymes accompanied by physiological neonatal outcomes. Our findings strongly suggest a placenta-mediated OxS inhibition in response to SARS-CoV-2 infection, thus contrasting the cytotoxic profile caused by Coronavirus Disease 2019 (COVID-19).

Oxidative Stress-Related Mechanisms in SARS-CoV-2 Infections

The COVID-19 pandemic caused relatively high mortality in patients, especially in those with concomitant diseases (i.e., diabetes, hypertension, and chronic obstructive pulmonary disease (COPD)). In most of aforementioned comorbidities, the oxidative stress appears to be an important player in their pathogenesis. The direct cause of death in critically ill patients with COVID-19 is still far from being elucidated. Although some preliminary data suggests that the lung vasculature injury and the loss of the functioning part of pulmonary alveolar population are crucial, the precise mechanism is still unclear. On the other hand, at least two classes of medications used with some clinical benefits in COVID-19 treatment seem to have a major influence on ROS (reactive oxygen species) and RNS (reactive nitrogen species) production. However, oxidative stress is one of the important mechanisms in the antiviral immune response and innate immunity. Therefore, it would be of interest to summarize the data regarding the oxidative stress in severe COVID-19. In this review, we discuss the role of oxidative and antioxidant mechanisms in severe COVID-19 based on available studies. We also present the role of ROS and RNS in other viral infections in humans and in animal models. Although reactive oxygen and nitrogen species play an important role in the innate antiviral immune response, in some situations, they might have a deleterious effect, e.g., in some coronaviral infections. The understanding of the redox mechanisms in severe COVID-19 disease may have an impact on its treatment.

The PI3K/Akt/mTOR pathway: A potential pharmacological target in COVID-19

Coronavirus disease 2019 (COVID-19) has emerged as a serious threat to global health. The disregulation of the phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/Akt/mTOR) cell signaling pathway observed in patients with COVID-19 has attracted attention for the possible use of specific inhibitors of this pathway for the treatment of the disease. Here, we review emerging data on the involvement of the PI3K/Akt/mTOR pathway in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and the clinical studies investigating its tailored inhibition in COVID-19. Current in silico, in vitro, and in vivo data convergently support a role for the PI3K/Akt/mTOR pathway in COVID-19 and suggest the use of specific inhibitors of this pathway that, by a combined mechanism entailing downregulation of excessive inflammatory reactions, cell protection, and antiviral effects, could ameliorate the course of COVID-19.

Contribution of Host miRNA-223-3p to SARS-CoV-Induced Lung Inflammatory Pathology

Severe acute respiratory syndrome coronavirus (SARS-CoV) and the closely related SARS-CoV-2 are emergent highly pathogenic human respiratory viruses causing acute lethal disease associated with lung damage and dysregulated inflammatory responses. SARS-CoV envelope protein (E) is a virulence factor involved in the activation of various inflammatory pathways. Here, we study the contribution of host miRNAs to the virulence mediated by E protein. Small RNAseq analysis of infected mouse lungs identified miRNA-223 as a potential regulator of pulmonary inflammation, since it was significantly increased in SARS-CoV-WT virulent infection compared to the attenuated SARS-CoV-ΔE infection. In vivo inhibition of miRNA-223-3p increased mRNA levels of pro-inflammatory cytokines and NLRP3 inflammasome, suggesting that during lung infection, miRNA-223 might contribute to restrict an excessive inflammatory response. Interestingly, miRNA-223-3p inhibition also increased the levels of the CFTR transporter, which is involved in edema resolution and was significantly downregulated in the lungs of mice infected with the virulent SARS-CoV-WT virus. At the histopathological level, a decrease in the pulmonary edema was observed when miR-223-3p was inhibited, suggesting that miRNA-223-3p was involved in the regulation of the SARS-CoV-induced inflammatory pathology. These results indicate that miRNA-223 participates in the regulation of E protein-mediated inflammatory response during SARS-CoV infection by targeting different host mRNAs involved in the pulmonary inflammation, and identify miRNA-223 as a potential therapeutic target in SARS-CoV infection.

Detection of COVID-19 severity using blood gas analysis parameters and Harris hawks optimized extreme learning machine

Coronavirus disease-2019 (COVID-19) has made the world more cautious about widespread viruses, and a tragic pandemic that was caused by a novel coronavirus has harmed human beings in recent years. The new coronavirus pneumonia outbreak is spreading rapidly worldwide. We collect arterial blood samples from 51 patients with a COVID-19 diagnosis. Blood gas analysis is performed using a Siemens RAPID Point 500 blood gas analyzer. To accurately determine the factors that play a decisive role in the early recognition and discrimination of COVID-19 severity, a prediction framework that is based on an improved binary Harris hawk optimization (HHO) algorithm in combination with a kernel extreme learning machine is proposed in this paper. This method uses specular reflection learning to improve the original HHO algorithm and is referred to as HHOSRL. The experimental results show that the selected indicators, such as age, partial pressure of oxygen, oxygen saturation, sodium ion concentration, and lactic acid, are essential for the early accurate assessment of COVID-19 severity by the proposed feature selection method. The simulation results show that the established methodlogy can achieve promising performance. We believe that our proposed model provides an effective strategy for accurate early assessment of COVID-19 and distinguishing disease severity. The codes of HHO will be updated in https://aliasgharheidari.com/HHO.html.

Peramivir, an Anti-Influenza Virus Drug, Exhibits Potential Anti-Cytokine Storm Effects

Coronavirus Disease 2019 (COVID-19) infected by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) has been declared a public health emergency of international concerns. Cytokine storm syndrome (CSS) is a critical clinical symptom of severe COVID-19 patients, and the macrophage is recognized as the direct host cell of SARS-CoV-2 and potential drivers of CSS. In the present study, peramivir was identified to reduce TNF-α by partly intervention of NF-κB activity in LPS-induced macrophage model. In vivo, peramivir reduced the multi-cytokines in serum and bronchoalveolar lavage fluid (BALF), alleviated the acute lung injury and prolonged the survival time in mice. In human peripheral blood mononuclear cells (hPBMCs), peramivir could also inhibit the release of TNF-α. Collectively, we proposed that peramivir might be a candidate for the treatment of COVID-19 and other infections related CSS.

COVID-19 and cancer: start the resolution!

Coronavirus disease 2019 (COVID-19) due to infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been an ongoing pandemic causing significant morbidity and mortality worldwide. The “cytokine storm” is a critical driving force in severe COVID-19 cases, leading to hyperinflammation, multi-system organ failure, and death. A paradigm shift is emerging in our understanding of the resolution of inflammation from a passive course to an active biochemical process driven by endogenous specialized pro-resolving mediators (SPMs), such as resolvins, protectins, lipoxins, and maresins. SPMs stimulate macrophage-mediated debris clearance and counter pro-inflammatory cytokine production, a process collectively termed as the “resolution of inflammation.” Hyperinflammation is not unique to COVID-19 and also occurs in neoplastic conditions, putting individuals with underlying health conditions such as cancer at elevated risk of severe SARS-CoV-2 infection. Despite approaches to block systemic inflammation, there are no current therapies designed to stimulate the resolution of inflammation in patients with COVID-19 or cancer. A non-immunosuppressive therapeutic approach that reduces the cytokine storm in patients with COVID-19 and cancer is urgently needed. SPMs are potent immunoresolvent and organ-protective lipid autacoids that stimulate the resolution of inflammation, facilitate clearance of infections, reduce thrombus burden, and promote a return to tissue homeostasis. Targeting endogenous lipid mediators, such as SPMs, offers an entirely novel approach to control SARS-CoV-2 infection and cancer by increasing the body’s natural reserve of pro-resolving mediators without overt toxicity or immunosuppression.

Targeting TNF-α for COVID-19: Recent Advanced and Controversies

Recent advances in the pathophysiologic understanding of coronavirus disease 2019 (COVID-19) suggests that cytokine release syndrome (CRS) has an association with the severity of disease, which is characterized by increased tumor necrosis factor α (TNF-α), interleukin (IL)-6, IL-2, IL-7, and IL-10. Hence, managing CRS has been recommended for rescuing severe COVID-19 patients. TNF-α, one of the pro-inflammatory cytokines commonly upregulated in acute lung injury, triggers CRS and facilitates SARS-CoV-2 interaction with angiotensin-converting enzyme 2 (ACE2). TNF-α inhibitors, therefore, may serve as an effective therapeutic strategy for attenuating disease progression in severe SARS-CoV-2 infection. Below, we review the possibilities and challenges of targeting the TNF-α pathway in COVID-19 treatment.

HACE2-Exosome-Based Nano-Bait for Concurrent SARS-CoV-2 Trapping and Antioxidant Therapy

Corona Virus Disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is seriously threatening human health. Following SARS-CoV-2 infection, immune cell infiltration creates an inflammatory and oxidative microenvironment, which can cause pneumonia, severe acute respiratory syndrome, kidney failure, and even death. Clinically, a safe and effective treatment strategy remains to be established. Herein, a nano-bait strategy for inhibition of SARS-CoV-2 infection by redirecting viral attack while simultaneously relieving inflammation is developed. Specifically, the nano-bait was based on the exosome-sheathed polydopamine (PDA@Exosome) nanoparticles, which were generated by exocytosis of the PDA nanoparticles from H293T cells. In this approach, PDA@Exosome inherits from the source cells of H293T cells a surface display of ACE2 through pre-engineered expression. The resulting PDA@Exosome can compete with ACE2-expressing epithelial cells for S protein binding, in either the pre-exposure or post-exposure route. Moreover, relying on the ability of PDA to intercept and deactivate radical species, the PDA@Exosome can significantly attenuate the level of inflammatory cytokines by mediating oxidative stress, a major cause of organ injury. Due to its high trapping, multiple antioxidant ability, and good biocompatibility, the HACE2-exosome based nano-bait is a promising robust antiviral nanotherapeutics for the ongoing COVID-19 pandemic.

Clinical Characteristics and Predictors of Mortality in Minority Patients Hospitalized with COVID-19 Infection

OBJECTIVES

To identify the early mortality predictors in minority patients hospitalized with coronavirus disease 2019 (COVID-19).

DESIGN

Demographics, presenting characteristics, admission laboratory data, ICU admission, and mortality data were collected from 200 consecutively hospitalized patients with COVID-19.

RESULTS

The mean (SD) age was 58.9 (15.1) years, 121(60.5%) were men, 143 (71.5%) were African Americans, and 33 (16.5%) were Latino. Common presenting symptoms were cough 130 (65.0%), shortness of breath 129 (64.5%), and fever 121 (60.5%). One or more comorbid illness occurred in 171 (85.5%) and common comorbidities were hypertension (130 (65.2%)), diabetes (100 (50.0%)) and chronic kidney disease (60 (30.0%)). Of the 200 patients, 71 (35.5%) were treated in the ICU, 47 (24.2%) received mechanical ventilation, 45 (22.5%) died, and 155(77.5%) patients discharged home alive. The non-survivors were significantly older and had elevated markers of inflammation, coagulation, and acute organ damage on presentation. Age ≥ 65 years (odds ratio (OR), 3.78; 95% CI, 1.74-8.22; P = .001), lactate dehydrogenase level > 400 IU/L (OR, 9.1; 95% CI, 2.97-28.1; p < 0.001), C-reactive protein > 20 mg/dl (OR, 5.56; 95%CI, 1.84-16.8; p < 0.001), ferritin > 2000 ng/ml (OR, 5.42; 95%CI, 1.63-17.9; p = 0.006), creatinine kinase > 1000 iu/l (OR, 3.57; 95% CI, 1.23 10.3; p = 0.019), procalcitonin > 2.5 ng/ml (OR, 4.21; 95% CI, 1.47-12.0; p = 0.007), D-dimer level > 3.0 μg/ml (OR,10.9; 95% CI, 3.33-36.2; p = < 0.001), creatinine > 2 mg/dl (OR, 4.5; 95% CI, 1.29-15.8; P = 0.018) at admission were associated independently with increases risk of in-hospital mortality.

CONCLUSION

Patients of advanced age that present with elevated biomarkers of inflammation, coagulation, and end-organ damage were at higher risk of mortality.

Advances in the development of therapeutic strategies against COVID-19 and perspectives in the drug design for emerging SARS-CoV-2 variants

Since Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) was identified in late 2019, the coronavirus disease 2019 (COVID-19) pandemic has challenged public health around the world. Currently, there is an urgent need to explore antiviral therapeutic targets and effective clinical drugs. In this study, we systematically summarized two main therapeutic strategies against COVID-19, namely drugs targeting the SARS-CoV-2 life cycle and SARS-CoV-2-induced inflammation in host cells. The development of above two strategies is implemented by repurposing drugs and exploring potential targets. A comprehensive summary of promising drugs, especially cytokine inhibitors, and traditional Chinese medicine (TCM), provides recommendations for clinicians as evidence-based medicine in the actual clinical COVID-19 treatment. Considering the emerging SARS-CoV-2 variants greatly impact the effectiveness of drugs and vaccines, we reviewed the appearance and details of SARS-CoV-2 variants for further perspectives in drug design, which brings updating clues to develop therapeutical agents against the variants. Based on this, the development of broadly antiviral drugs, combined with immunomodulatory, or holistic therapy in the host, is prior to being considered for therapeutic interventions on mutant strains of SARS-CoV-2. Therefore, it is highly acclaimed the requirements of the concerted efforts from multi-disciplinary basic studies and clinical trials, which improves the accurate treatment of COVID-19 and optimizes the contingency measures to emerging SARS-CoV-2 variants.

Immune Profiling of COVID-19 in Correlation with SARS and MERS

Acute respiratory distress syndrome (ARDS) is a major complication of the respiratory illness coronavirus disease 2019, with a death rate reaching up to 40%. The main underlying cause of ARDS is a cytokine storm that results in a dysregulated immune response. This review discusses the role of cytokines and chemokines in SARS-CoV-2 and its predecessors SARS-CoV and MERS-CoV, with particular emphasis on the elevated levels of inflammatory mediators that are shown to be correlated with disease severity. For this purpose, we reviewed and analyzed clinical studies, research articles, and reviews published on PubMed, EMBASE, and Web of Science. This review illustrates the role of the innate and adaptive immune responses in SARS, MERS, and COVID-19 and identifies the general cytokine and chemokine profile in each of the three infections, focusing on the most prominent inflammatory mediators primarily responsible for the COVID-19 pathogenesis. The current treatment protocols or medications in clinical trials were reviewed while focusing on those targeting cytokines and chemokines. Altogether, the identified cytokines and chemokines profiles in SARS-CoV, MERS-CoV, and SARS-CoV-2 provide important information to better understand SARS-CoV-2 pathogenesis and highlight the importance of using prominent inflammatory mediators as markers for disease diagnosis and management. Our findings recommend that the use of immunosuppression cocktails provided to patients should be closely monitored and continuously assessed to maintain the desirable effects of cytokines and chemokines needed to fight the SARS, MERS, and COVID-19. The current gap in evidence is the lack of large clinical trials to determine the optimal and effective dosage and timing for a therapeutic regimen.

Effect of Jinzhen granule on two coronaviruses: The novel SARS-CoV-2 and the HCoV-229E and the evidences for their mechanisms of action

BACKGROUND

Although severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and human coronavirus 229E (HCoV-229E) pose a huge threat to human public health, no specific treatment is available. Jinzhen granule (JZ) is a traditional eight ingredients-Chinese medicine with prominent efficacy for treating viral-induced diseases. However, little is known about the antiviral effect and mechanism of JZ against SARS-CoV-2 and HCoV-229E.

PURPOSE

This study aimed to reveal the antiviral effects of JZ against SARS-CoV-2 and HCoV-229E, and to further explore the underlying mechanisms regulating the host immune response.

METHODS

The chromatographic separation of JZ was performed using a Shimadzu analytical high-performance liquid chromatograph with UV detection and Alltech ELSD 2000ES. We conducted cytopathic effect (CPE) and plaque reduction assays to evaluate the antiviral effect of JZ. A lethal human angiotensin converting enzyme 2 (hACE2) transgenic mouse model of SARS-CoV-2 was established to determine the protective effect of JZ on mortality and lung virus titers. Real-time quantitative PCR assays were used to analyze the expression of proinflammatory cytokines in vitro and in vivo. Western blotting was further performed to determine the activities on regulating the nuclear factor kappa B (NF-κB)/MAPK pathway. Finally, mitochondrial membrane potential assays, flow cytometry analysis and western blotting were used to assess the anti-apoptotic potency toward HCoV-229E infection.

RESULTS

The results showed that 13 chemical components were identified and five peaks were determined and quantitated (gallic acid 1.97 mg/g, baicalin 20.69 mg/g, glycyrrhizic acid 4.92 mg/g, hyodeoxycholic acid 4.86 mg/g, cholic acid 4.07 mg/g). We found that JZ exerted inhibitory potency against SARS-CoV-2 and HCoV-229E in vitro by using CPE and plaque reduction assays, and it was further found that JZ protected mice infected by SARS-CoV-2 from death and inhibited lung virus titers. JZ also significantly decreased the induction of inflammatory cytokines (IL-1α, IL-6, CCL-5 and MIP-1β), similar to the observed in vitro effect. Moreover, JZ suppressed the release of inflammatory cytokines in vitro and it decreased the protein expression of p-p38 MAPK, p-JNK, p-NF-κB p65 and p-IκBα induced by HCoV-229E and increased the expression of IκBα. Notably, JZ significantly protected HCoV-229E-infected Huh-7 cells from mitochondrial damage and decreased apoptotic cells. The activation of the mitochondria-mediated apoptotic pathway was inhibited by JZ, as shown by the reduced expression of cleaved caspase-9, caspase-3 and p-PARP.

CONCLUSIONS

In conclusion, JZ (gallic acid 1.97 mg/g, baicalin 20.69 mg/g, glycyrrhizic acid 4.92 mg/g, hyodeoxycholic acid 4.86 mg/g, cholic acid 4.07 mg/g) exhibited antiviral activities against SARS-CoV-2 and HCoV-229E by regulating the NF-κB/MAPK pathway and the mitochondria-mediated apoptotic pathway. These findings demonstrated the efficacy of JZ against CoVs and suggested JZ treatment as a novel clinical therapeutic strategy for COVID-19.