Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China

DEELE-Rad: exploiting deep radiomics features in deep learning models using COVID-19 chest X-ray images

Purpose

Deep learning-based radiomics techniques have the potential to aid specialists and physicians in performing decision-making in COVID-19 scenarios. Specifically, a Deep Learning (DL) ensemble model is employed to classify medical images when addressing the diagnosis during the classification tasks for COVID-19 using chest X-ray images. It also provides feasible and reliable visual explicability concerning the results to support decision-making.

Methods

Our DEELE-Rad approach integrates DL and Machine Learning (ML) techniques. We use deep learning models to extract deep radiomics features and evaluate its performance regarding end-to-end classifiers. We avoid successive radiomics approach steps by employing these models with transfer learning techniques from ImageNet, such as VGG16, ResNet50V2, and DenseNet201 architectures. We extract 100 and 500 deep radiomics features from each DL model. We also placed these features into well-established ML classifiers and applied automatic parameter tuning and a cross-validation strategy. Besides, we exploit insights into the decision-making behavior by applying a visual explanation method.

Results

Experimental evaluation on our proposed approach achieved 89.97% AUC when using 500 deep radiomics features from the DenseNet201 end-to-end classifier. Besides, our ensemble DEELE-Rad method improves the results up to 96.19% AUC for the 500 dimensions. To outperform, ML DEELE-Rad reached the best results with an Accuracy of 98.39% and 99.19% AUC for the same setup. Our visual assessment employs additional possibilities for specialists and physicians to decision-making.

Conclusion

The results reflect that the DEELE-Rad approach provides robustness and confidence to the images' analysis. Our approach can benefit healthcare specialists when employed at clinical routines and respective decision-making procedures. For reproducibility, our code is available at https://github.com/usmarcv/deele-rad.

Immunogenicity and safety of a COVID-19 DNA vaccine in healthy adults and elderly: A randomized, observer-blind, placebo-controlled phase 2 trial

INO-4800 represents a DNA-based vaccine encoding the spike protein of SARS-CoV-2. This phase 2 trial evaluated the immunogenicity and safety of INO-4800 as a primary vaccination series in adults. We conducted a randomized, observer-blind, placebo-controlled phase 2 trial of intradermal injection of INO-4800 in both healthy adults and elderly individuals. Eligible participants from each age group were enrolled and randomly assigned in a 3:3:2 ratio to receive two doses of INO-4800 (1.0 mg or 2.0 mg) or placebo, followed by electroporation on day 0 and day 28. The primary immunogenicity endpoints focused on determining the geometric mean titers (GMTs) of spike-binding antibodies and live SARS-CoV-2 neutralizing antibody at day 30 after the second dose. The primary endpoint for safety was the occurrence of adverse events within 30 days after vaccination. A total of 781 volunteers were recruited and screened for eligibility, with 320 eligible young adults (≥18 to <60 years old) and 320 elderly (≥60 to ≤85 years old) were randomly assigned to receive the low-dose (1.0 mg, n = 120) or high-dose (2.0 mg, n = 120) INO-4800, or placebo (n = 80). Notably, both dose groups exhibited significant increases in spike-binding antibodies at day 30 after the second dose, with GMTs of 1609.3 (95% CI: 1385.5-1869.3) for the low-dose group and 3016.7 (95% CI: 2577.4-3530.8) for the high-dose group. Additionally, both dose groups induced neutralizing antibodies against live SARS-CoV-2, with GMTs of 4.7 (95% CI: 4.2-5.3) and 6.6 (95% CI: 5.9-7.4) at day 30 after the second dose. The incidence of adverse events within 30 days after vaccination was slightly higher in the high-dose group (115 [47.9%]) than that in the low-dose group (105 [43.8%]) (p = .0060). All adverse reactions were grade 1 or 2, primarily occurring within 14 days after vaccination. No vaccine-related serious adverse events were reported. The COVID-19 DNA vaccine INO-4800 at two doses (1.0 mg or 2.0 mg) showed an acceptable safety profile and modest immunogenicity, with the high-dose slightly more immunogenic than the low-dose.Clinical Trials Registration: www.chictr.org.cn, identifier is ChiCTR2000040146.

Apium graveolens L. alleviates acute lung injury in human A-549 cells by reducing NF-κB and NLRP3 inflammasome signaling

BACKGROUND

Apium graveolens L. (celery) is a dietary vegetable with anti-inflammatory properties. It has the potential to treat acute lung injury (ALI) caused by COVID-19 or other diseases.

OBJECTIVE

To investigate the effects of Apium graveolens water extract (AGWE) on ALI in human lung A-549 cells induced by lipopolysaccharide (LPS).

MATERIALS AND METHODS

A-549 cells were treated with AGWE for 24 h and then stimulated with 10 μg/mL LPS for another 24 h. The effects of AGWE on cell viability, the inflammatory response, oxidative stress, and apoptosis and their regulatory factors, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), and NLR family pyrin domain containing 3 (NLRP3) inflammasome signaling activation were analyzed.

RESULTS

Treatment with 5-50 μg/mL AGWE reversed the decrease in cell viability caused by LPS (p < 0.05). AGWE can reduce interleukin (IL)-1β, IL-6, IL-18, and TNF-α levels; their EC50 values are 61.4, 65.7, 37.8, and 79.7 μg/mL, respectively. AGWE can reduce reactive oxygen species and thiobarbituric acid reactive substances in A-549 cells induced by LPS. AGWE also reduced the levels of apoptosis (EC50 of 74.8 μg/mL) and its regulators (Bid; Caspase-9, -8, and -3; Bax) and increased the levels of the mitochondrial membrane potential in A-549 cells induced by LPS. AGWE can also decrease the protein levels of NLRP3 and Caspase-1 and the activation of NF-κB signaling in A-549 cells induced by LPS.

CONCLUSIONS

These results show that 10 and 50 μg/mL AGWE can reduce the acute inflammation induced by LPS by reducing NF-κB and NLRP3 inflammasome signaling and mitochondria-dependent apoptosis pathways.

Exploring the biological mechanisms of severe COVID-19 in the elderly: Insights from an aged mouse model

The elderly population, who have increased susceptibility to severe outcomes, have been particularly impacted by the coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), leading to a global health crisis. However, definitive parameters or mechanisms underlying the severity of COVID-19 in elderly people remain unclear. Thus, this study seeks to elucidate the mechanism behind the increased vulnerability of elderly individuals to severe COVID-19. We employed an aged mouse model with a mouse-adapted SARS-CoV-2 strain to mimic the severe symptoms observed in elderly patients with COVID-19. Comprehensive analyses of the whole lung were performed using transcriptome and proteome sequencing, comparing data from aged and young mice. For transcriptome analysis, bulk RNA sequencing was conducted using an Illumina sequencing platform. Proteomic analysis was performed using mass spectrometry following protein extraction, digestion, and peptide labelling. We analysed the transcriptome and proteome profiles of young and aged mice and discovered that aged mice exhibited elevated baseline levels of inflammation and tissue damage repair. After SARS-CoV-2 infection, aged mice showed increased antiviral and inflammatory responses; however, these responses were weaker than those in young mice, with significant complement and coagulation cascade responses. In summary, our study demonstrates that the increased vulnerability of the elderly to severe COVID-19 may be attributed to an attenuated antiviral response and the overactivation of complement and coagulation cascades. Future research on antiviral and inflammatory responses is likely to yield treatments that reduce the severity of viral respiratory diseases in the elderly.

Exploring the association between happy hypoxia and Coronavirus disease 2019 in the triage phase

BACKGROUND

Patients with severe coronavirus disease 2019 (COVID-19) have been reported to show hypoxia without displaying typical clinical signs or symptoms, called "happy hypoxia." To explore the potential of happy hypoxia as a distinctive symptom of COVID-19, we compared vital signs in the triage phase between patients with and without COVID-19.

METHODS

We retrospectively identified emergency patients with and without COVID-19 admitted to Rakuwakai Marutamachi Hospital, Kyoto, Japan, between January 2021 and December 2021.

RESULTS AND CONCLUSIONS

317 patients were analyzed. Multivariate logistic regression analysis, including all vital signs, demonstrated that the respiratory rate was not statistically associated with COVID-19 (odds ratio, 0.94, p = 0.058), suggesting that happy hypoxia may not be a distinct hallmark of COVID-19.

Long-term alveolar-capillary diffusion impairments after severe SARS-CoV-2 pneumonia

BACKGROUND

Persistent respiratory symptoms and impaired gas exchange are common in patients recovering from COVID-19 pneumonia. The Lung Diffusing Capacity for Carbon Monoxide (DLCO) and Carbon Monoxide Transfer Coefficient (KCO) do not adequately distinguish alveolar membrane dysfunction from vascular abnormalities. This study aimed to characterize persistent diffusion impairment in post-ICU patients with prior SARS-CoV-2 pneumonia and reduced DLCO.

METHODS

After hospital discharge, patients underwent spirometry, DLCO measurement, and a 6-minute walking test every six months. If DLCO remained impaired at 18-24 months, a combined Lung Diffusing Capacity for Nitric Oxide (DLNO) and DLCO assessment was performed to differentiate alveolar-capillary membrane (DmCO) and pulmonary capillary blood volume (Vc) alterations.

RESULTS

Among 20 patients with persistent DLCO reduction, 3 had an obstructive ventilatory pattern, 6 had restriction, and 12 had low KCO. In restrictive cases, KCO was reduced but remained within normal limits without compensation. The DLNO/DLCO ratio exceeded 113.5% predicted in all patients. DmCO was impaired in 7 patients, while Vc was reduced in 16.

CONCLUSION

Both DLCO determinants were affected, with vascular impairment predominating. Vc reduction was present in most patients, with mean values below the lower limit of normality, whereas DmCO was less affected and often normal. The elevated DLNO/DLCO ratio suggests that persistent DLCO reduction is primarily driven by prolonged pulmonary capillary circulation dysfunction rather than alveolar membrane alterations, highlighting the vascular component as the primary site of long-term impairment.

Optimizing the pharmacokinetics and selectivity of TMPRSS2 inhibitors

Since 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has undergone significant genomic mutations, contributing to resistance against existing 2019 coronavirus disease (COVID-19) treatments. In a previous study, we identified N-0385, a potent host-directed inhibitor of transmembrane serine protease 2 (TMPRSS2), which has therapeutic efficacy towards SARS-CoV-2 infection. However, in further evaluation of its preclinical druggability, N-0385 displayed unfavorable pharmacokinetic properties, including high bioavailability (99 %) following intranasal (IN) administration. This can lead to substantial systemic exposure and potential adverse effects due to off-target interactions. Here, we designed a library of peptidomimetic compounds with P3 site modifications on an optimized scaffold. We sought to maintain sub-nanomolar potency against TMPRSS2 (Kis < 2 nM), reduce pseudovirus infection, while addressing the lack of selectivity and excessive lung uptake. Notably, inhibitor 9, which contains Asp at the P3 position, achieved a two-fold increase in TMPRSS2 inhibitory potency (Ki = 0.13 ± 0.03 nM), a >700-fold selectivity over Factor Xa (FXa), and showed superior selectivity against other proteases (matriptase, transmembrane serine protease 6 (TMPRSS6), thrombin, furin, and tPA). Despite concerns about the role of FXa in the coagulation cascade, compound 9 had no impact on coagulation or thrombolysis 2 h after in vitro treatment. In the air-liquid interface (ALI) model of the lung epithelium, compound 9 displayed a 1.5-fold decrease in permeability compared to N-0385 and demonstrated sustained stability in lungs (11 h) and plasma (13 h). Taken together, our data demonstrate that continued optimization of this type of inhibitors will lead to improved therapeutics for the treatment of SARS-CoV-2 infection by IN administration.

Dynamics of an epidemic controlled by isolation and quarantine: A probability-based deterministic model

Assuming a homogeneous population, we employ a deterministic model based on first principles of probability to explore dynamics of an epidemic controlled by isolation alone, quarantine alone, and the two together. We develop explicit closed-form equations for key metrics of control performance: cumulative fraction of population infected over the course of the epidemic (final size), maximum fraction infected at any one time, and epidemic duration. We derive an analytical solution for final size of an epidemic controlled by isolation, when final size is small, and develop empirical relations for the other cases. We frame equations in terms of reproduction numbers, measures of intervention effort and initial conditions. We model both strength and speed of interventions, assume second order gamma distributions for intervention waiting times and employ non-time-invariant equations for quarantine. We also account for quarantine of unexposed, susceptible individuals and for imperfect intervention.

Porous poly (lactic-co-glycolic acid) microspheres loaded with neutral and acidic ginseng polysaccharides ameliorate pneumonia in mice

In this study, porous poly (lactic-co-glycolic acid) (PLGA) microspheres loaded with ginseng polysaccharides were successfully prepared and used to ameliorate pneumonia in mice. Fourier transform infrared spectroscopy, and confocal laser scanning microscopy confirmed the successful preparation of porous PLGA microspheres loaded with neutral ginseng polysaccharides (GP-N) and acidic ginseng polysaccharides (GP-S). Porous PLGA microspheres loaded with GP-N and GP-S had good release profiles. In vitro tests revealed that the release solution of porous PLGA microspheres loaded with GP-N and GP-S was nontoxic. The release solutions of porous PLGA microspheres loaded with GP-N and GP-S can both effectively reduce tumor necrosis factor-α (TNF-α), interleukin (IL)-6, and IL-1β. Porous PLGA microspheres loaded with GP-N and GP-S ameliorated mouse pneumonia by modulating cytokine levels and antioxidant enzyme activities. Porous microspheres loaded with GP-S exhibited more potent anti-inflammatory effects than those loaded with GP-N. This phenomenon may be attributed to the presence of uronic acid in the GP-S. Transcriptomics revealed that the potential anti-pneumonia mechanism of porous PLGA microspheres loaded with GP-S may ameliorate pneumonia in mice through cytochrome P450 drug metabolism, arachidonic acid metabolism, and MAPK signaling pathways. These findings provide a theoretical basis for the amelioration of pneumonia using ginseng polysaccharides.

Virus-specific antibody responses in severe acute respiratory syndrome coronavirus 2-infected and vaccinated individuals

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can have a serious course with many complications, especially in immunocompromised individuals. In such persons, other latent virus infections may contribute to disease pathology, in particular viruses which infect immune cells such as Epstein-Barr virus (EBV) and cytomegalovirus (CMV).

METHODS

In this study, serology-based assays were conducted to analyse antibody responses to SARS-CoV-2 spike protein (SP), EBV Epstein-Barr nuclear antigen (EBNA)-1 and CMV phosphoprotein (pp)52 in naturally SARS-CoV-2-infected individuals, non-infected healthy controls (HCs) and vaccinated healthy controls (VHCs) to identify an association between SARS-CoV-2 antibodies and EBV and CMV antibodies in order to determine whether latent EBV and CMV infected individuals are more prone to become infected with SARS-CoV-2. Moreover, SARS-CoV-2, EBV, and CMV antibody responses were characterized in serum from patients with relapsing-remitting multiple sclerosis (RRMS), a chronic inflammatory disease strongly associated with EBV infections, to determine whether the serologic virus antibody profile varies in immunocompromised RRMS individuals upon SARS-CoV-2 vaccinations compared to VHCs.

RESULTS

Significantly elevated SP IgG, IgM and IgA levels were identified in SARS-CoV-2-infected immunocompetent individuals when compared to non-infected HCs. However, no correlation was found to serum antibodies between SARS-CoV-2, EBV, and CMV in individuals infected with SARS-CoV-2 and in VHCs, suggesting that latent infections with neither EBV nor CMV associates to SARS-CoV-2 infection. Moreover, no significant difference in SP IgG, IgA and IgM levels was observed between vaccinated RRMS patients and VHCs, indicating that the immune system of immune deficient RRMS patients and VHCs respond identical to SARS-CoV-2 vaccinations.

CONCLUSION

Collectively, SARS-CoV-2 SP antibody levels reflect the vaccination and infection history and do not associate with EBV and CMV serostatus.

Agomelatine attenuates dexamethasone-induced neurotoxicity in rats through the activation of MT1/2 receptors and attenuation of oxidative stress

Previous studies showed that agomelatine ameliorates doxorubicin-induced brain injury in rats. Furthermore, it protects neurons against oxidative stress triggered by acute ischemia reperfusion injury. So, this study aimed to investigate the possible neuroprotective effects of agomelatine on dexamethasone-induced neurotoxicity in rats and the underlying mechanisms. Subcutaneous injections of dexamethasone (10 mg/kg, 4 days) were used to induce neurotoxicity in rats. Agomelatine (10 mg/kg), luzindole (2.5 mg/kg, a melatonin receptor blocker), and luzindole plus agomelatine treatment commenced 3 days before dexamethasone injections and concurrent with dexamethasone injections. Elevated plus maze test, Y-maze test and open field test were carried out after 1 h of the last dose of dexamethasone on day 7. On 8th day of the experiment, brain tissues were collected. Brain oxidative stress markers, immunohistochemical expression of β-amyloid and glial fibrillary acidic protein (GFAP) were measured. Moreover, histopathological changes in the cerebral cortex and hippocampus were recorded and the number of damaged cells was counted. Dexamethasone increased anxiety and memory impairment but decreased locomotor exploration activity. Furthermore, it increased brain oxidative stress, expression of β-amyloid and GFAP, increased the number of damaged neurons, and caused structural changes in cerebral cortex and hippocampus. All these deleterious changes were mitigated by agomelatine. Luzindole prior administration to agomelatine reversed the protective effects of agomelatine except its effect on lipid peroxidation. Collectively, these findings suggest that agomelatine can protect against dexamethasone-induced neurotoxicity partially by activating melatonin receptors in addition to exerting antioxidant effects.

Respiratory function and sleep parameters in adults following recovery from acute COVID-19

The impact of COVID-19 on lung function and sleep in otherwise healthy individuals has been subject to a limited number of studies. The aim of this study was to investigate the effect of COVID-19 on pulmonary function and sleep in adults. Participants, 50-85 years old, who had recovered from COVID-19 (COVID-19 group: n = 48) and those without history of COVID-19 (control group: n = 28) underwent pulmonary function assessment (Forced Vital Capacity, FVC, and Slow Vital Capacity, SVC) using spirometry. Sleep and circadian variables were measured objectively with wrist-worn actigraphy for seven days. Subjective sleep of participants was assessed using the Pittsburgh Sleep Quality Index (PSQI). There were no significant differences in age (60 ± 6 vs 62 ± 6 years), BMI (26.30 ± 4.25 vs 26.48 ± 3.60 kg/m2), or pulmonary function (FVC, 4.02 ± 1.04 vs 3.80 ± 0.98 L, p = 0.36; and SVC, 3.82 ± 1.09 vs 3.89 ± 0.92 L, p = 0.76) between COVID-19 and control groups. The COVID-19 group had significantly reduced sleep efficiency (0.87 ± 0.04 vs 0.91 ± 0.04, p < 0.01), increased sleep disturbance (awakenings, 1.70 ± 1.02 vs 1.15 ± 1.15, p < 0.01; and wakefulness after sleep onset, 35:05 ± 25:37 vs 20:02 ± 12:48 min, p = 0.01) and PSQI score (5.19 ± 2.88 vs 3.93 ± 2.89, p = 0.01), compared to the control group. Individuals with history of COVID-19 demonstrate reduced sleep quality compared to a non-COVID-19 control group.

Phillyrin for sepsis-related acute lung injury: A potential strategy suppressing GSK-3β

The efficacy of clinical drugs for acute lung injury/acute respiratory distress syndrome (ALI/ARDS) remains suboptimal. Phillyrin (PHN), a compound derived from Forsythia, is believed to alleviate sepsis-related ALI/ARDS; however, its mechanisms are not fully elucidated. In this study, we screened 8331 target genes associated with ALI/ARDS from public databases and identified six hub genes relevant to PHN treatment: AKT1, GSK-3β, PPP2CA, PPP2CB, PPP2R1A, and AR. Receiver operating characteristic analysis and single-cell sequencing analysis revealed the expression of AKT1, GSK-3β, PPP2CA, PPP2CB, and PPP2R1A were markedly elevated. Molecular docking and dynamics simulations indicated that PHN forms a structurally stable complex with glycogen synthase kinase-3β (GSK-3β). Mendelian randomization analyses suggested that PHN, as a potent GSK-3β inhibitor, may promote M2 macrophage polarization and reduce neutrophil recruitment. We validated these findings through in vivo and in vitro experiments, demonstrating that PHN lowers iNOS levels and raises MMR levels by downregulating GSK-3β mRNA expression and protein activity during lipopolysaccharide (LPS)-induced macrophage inflammation. Additionally, PHN inhibited GSK-3β mRNA expression and protein activity, reducing NF-κB-p65 nuclear translocation in LPS-induced zebrafish inflammation and mice ALI. This inhibition decreased levels of TNF-α and IL-6, increased IL-10 levels, promoted M2 macrophage polarization, suppressed neutrophil recruitment, and ultimately ameliorated ALI/ARDS. In conclusion, our results indicate that PHN effectively alleviates LPS-induced ALI/ARDS by suppressing GSK-3β signaling.

Micronutrients, Vitamin D, and Inflammatory Biomarkers in COVID-19: A Systematic Review and Meta-analysis of Causal Inference Studies

CONTEXT

Experimental and observational studies suggest that circulating micronutrients, including vitamin D (VD), may increase COVID-19 risk and its associated outcomes. Mendelian randomization (MR) studies provide valuable insight into the causal relationship between an exposure and disease outcomes.

OBJECTIVES

The aim was to conduct a systematic review and meta-analysis of causal inference studies that apply MR approaches to assess the role of these micronutrients, particularly VD, in COVID-19 risk, infection severity, and related inflammatory markers.

DATA SOURCES

Searches (up to July 2023) were conducted in 4 databases.

DATA EXTRACTION AND ANALYSIS

The quality of the studies was evaluated based on the MR-STROBE guidelines. Random-effects meta-analyses were conducted where possible.

RESULTS

There were 28 studies (2 overlapped) including 12 on micronutrients (8 on VD) and COVID-19, 4 on micronutrients (all on VD) and inflammation, and 12 on inflammatory markers and COVID-19. Some of these studies reported significant causal associations between VD or other micronutrients (vitamin C, vitamin B6, iron, zinc, copper, selenium, and magnesium) and COVID-19 outcomes. Associations in terms of causality were also nonsignificant with regard to inflammation-related markers, except for VD levels below 25 nmol/L and C-reactive protein (CRP). Some studies reported causal associations between cytokines, angiotensin-converting enzyme 2 (ACE2), and other inflammatory markers and COVID-19. Pooled MR estimates showed that VD was not significantly associated with COVID-19 outcomes, whereas ACE2 increased COVID-19 risk (MR odds ratio = 1.10; 95% CI: 1.01-1.19) but did not affect hospitalization or severity of the disease. The methodological quality of the studies was high in 13 studies, despite the majority (n = 24) utilizing 2-sample MR and evaluated pleiotropy.

CONCLUSION

MR studies exhibited diversity in their approaches but do not support a causal link between VD/micronutrients and COVID-19 outcomes. Whether inflammation mediates the VD-COVID-19 relationship remains uncertain, and highlights the need to address this aspect in future MR studies exploring micronutrient associations with COVID-19 outcomes.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42022328224.

Oxidative stress and PARP activation in the lungs is an early event in COVID-19 pneumonia

Oxidative stress and poly(ADP-ribosyl)ation (PARylation) leads to tissue damage and inflammation in multiple lung diseases, likely in COVID-19. In a previous study we evidenced PARylation in multiple pulmonary cell types in patients who died of COVID-19, but not in patients who died of non-COVID-19 causes. We extended these observations in this retrospective immunohistochemical study by enlarging and stratifying the study population to identify subpopulations with high expression of the markers assessed in the study. We showed that pulmonary PARylation and oxidative stress peaked in the exudative and then decreased in the proliferative phase. PARylation correlated with viral load and with the oxidative stress in the tissues, however, correlation between viral load and oxidative stress was marginal suggesting that oxidative stress and the presence of SARS-CoV-2 can independently induce PARylation. Pulmonary oxidative stress, PARylation and TNFα expression correlated with the serum markers of liver and kidney damage, oxygen transport, tissue hypoxia, lymphocytopenia, blood clotting and disseminated intravascular coagulation. In males the time of hospitalization (time to death) was inversely correlated with pulmonary PARylation. Furthermore, males, died of COVID-19, were ∼15 years younger than females, however, there was no difference in pulmonary oxidative stress and PARylation between genders at death. Taken together, pulmonary PARylation and oxidative stress manifests early, in the exudative phase of COVID-19 and PARylation contributes to worse clinical outcome for males. These results suggest repurposing pharmacological PARP inhibitors for acute COVID-19 to counteract tissue damage.

Heart failure and co-morbidities confer a negative prognosis in COVID-19 infection

BACKGROUND

Since early reports, it has been shown that cardiovascular (CV) diseases, including heart failure (HF), represent a risk factor for infection, hospital admissions and mortality from COVID-19. The COVID-19 pandemics has been of major importance in Italy and in the Lombardy Region. Aims of this study were to compare COVID-19 infection in HF and No-HF subjects, and to quantify among HF patients the risk for COVID-19 infection and all-cause mortality.

METHODS

All consecutive patients (98,549) with at least one hospital discharge of HF (primary diagnosis) during January 1st, 2015, to December 31st, 2019, were identified in the Lombardy Region Database (>10 million inhabitants), and compared with No-HF subjects (394,104 with a lower age limit 40 years), randomly chosen in a 4:1 proportion among hospitalized patients. The whole cohort of cases of COVID-19 infection, laboratory-confirmed by RT-PCR, aged >40 years, diagnosed from the beginning of the epidemic on 21 February 2020 to 1 October 2020 was studied. The study outcomes were: occurrence, hospitalization, and death in COVID-19 cases.

RESULTS

Incidence of COVID-19 increased with age in both HF (p < 0.001) and No-HF patients (p < 0.001); cases (and incidence rates, IR) were 8648 (IR = 29.653 × 100.000) in HF and 14,256 (IR = 10.195) and in No-HF (p < 0.001); hospital admissions were 4974 (IR = 14.970) and 4943 (IR = 3.484), respectively (p 〈0001); deaths were 7650 (IR = 5.368) and 18,368 (IR = 56.921), respectively (p < 0.001); the incidence rate ratio (IRR) was 2.909 (95 % C.I. 2.908-2.909) for infection (p < 0.001), 4.297 (95 % C.I. 4.296-4.297) for hospital admission (p < 0.001), and 10.603 (95 % C.I.10.602-10.604) for mortality (p < 0.001). The excess IRR for mortality varied from 25.001 (95 % C.I. 24.971-25.032) for the age decade 40-49 to 1.925 (95 % C.I. 1.923-1.926) for the age decade 100-109. Among HF patients, age (OR = 1.087, 95 % C.I.1.05-1.088), male sex (OR = 1.27, 95 % C.I. 1.23-1.31), number of hospital admissions for HF during the period 2015-2019 (OR = 2.22, 95 % C.I. 2.11-2.33), co-morbidities (OR = 1.33, 95 % C.I. 1.32-1.35), or Charlson Index (OR = 1.21, 95 % C.I. 1.20-1.22), were risk factors for both infection and all-cause mortality at univariable and at multivariable analysis.

CONCLUSION

Infections, hospital admissions, and mortality for COVID-19 increased with age and male sex were more frequent in HF than in No-HF patients. Among HF patients, age and sex, number of hospital admissions for HF, co-morbidities, were risk factors for both infection and mortality. These data are of relevance for prioritizing interventions for prevention of infection, and for assistance to patients with COVID-19, and to inform management of future pandemics.

Hepatic dysfunction in individuals with COVID-19 and its impact on pregnancy outcomes

This study aimed to describe the incidence of abnormal liver function tests (LFTs) in pregnant women post-2019 coronavirus disease (COVID-19) and investigate the characteristics of pregnant women with abnormal LFTs and its impact on pregnancy outcomes. The data for 168 pregnant women who were infected with COVID-19 in the late stages of pregnancy were collected in Hefei Maternal and Child Health Hospital from December 2022 to January 2023, and 86 pregnant women with abnormal liver function were divided into the research group and 82 pregnant women with normal liver function into the control group for retrospective analysis. Population and laboratory data were collected and statistical analysis was conducted. Among the 168 pregnant women with COVID-19, 86 (51.2%) had elevated liver enzymes. In the control group, 4 (4.5%) had elevated liver enzymes. Differences between the 2 groups were statistically significant (P < .05). Single-factor analysis revealed that age, gestational week, and body mass index (BMI) exhibited statistically significant differences (P < .001) as potential factors influencing abnormal LFTs. Logistic regression analysis demonstrated that age (OR: 1.526), gestational week (OR: 1.321), and BMI (OR: 1.159) remained independent risk factors for liver injury (P < .05). Furthermore, the cesarean section rate, postpartum hemorrhage rate, rupture of membranes rate, and fetal intrauterine distress rate in the observation group were all significantly higher than those in the control group (P < .05). Additionally, the incidence of neonatal asphyxia, preterm birth, and low birth weight in the observation group were all significantly higher than those in the control group (P < .05). Pregnant individuals are at an elevated risk of hepatic injury following severe acute respiratory syndrome coronavirus 2 infection. Furthermore, the likelihood of hepatic injury escalates with advancing maternal age, gestational age, and BMI. Hepatic functional aberrations in the latter stages of pregnancy may precipitate adverse pregnancy outcomes.

Tumour necrosis factor-alpha inhibitors decrease mortality in COVID-19: a systematic review and meta-analysis

BACKGROUND

Despite widespread vaccination efforts, effective treatment strategies remain critical for severe SARS-CoV-2 infection. Tumour necrosis factor-alpha (TNF-α) plays a central role in the cytokine storm characteristic of severe COVID-19. This systematic review and meta-analysis evaluates the effectiveness, efficacy, and safety of TNF-α inhibitors in the management of COVID-19.

PATIENTS AND METHODS

A systematic review of PubMed, Embase, and CENTRAL was conducted, focusing on studies involving SARS-CoV-2-infected patients treated with TNF-α inhibitors compared with those receiving standard of care without prior TNF-α inhibitor use. Data from studies published up to August 12, 2024, were analysed. Outcomes assessed included mortality, invasive mechanical ventilation, and C-reactive protein (CRP) levels. Odds ratios (ORs) and mean differences (MD) were calculated with 95% confidence intervals (CI), and subgroup analyses were performed for randomised controlled trials (RCTs) and non-randomised studies.

RESULTS

Seven studies involving 1393 patients with moderate-to-critical COVID-19 were included. TNF-α inhibitor treatment was associated with a reduced odds of mortality (OR 0.67, 95% CI [0.44-1.00], P = 0.052), which was statistically significant in the RCT subgroup across three studies (OR 0.75, 95% CI [0.58-0.97], P = 0.042, certainty of evidence: very low). The number needed to treat for mortality was calculated to be 16 (95% CI 9.0-inf.), which indicates that one additional death could be avoided for every 16 patients treated with TNF-α inhibitors compared to standard of care. No significant reduction in the need for invasive mechanical ventilation was observed (OR 0.95 [95% CI 0.46-1.94]; P = 0.822). Additionally, TNF-α inhibitors resulted in a significant reduction in CRP levels (MD - 21.9 mg/L [95% CI - 38.46 to - 5.34]; P = 0.024) within three to seven days post-treatment.

CONCLUSION

Our study indicates a potential role for TNF-α inhibition in the treatment of COVID-19 as their use was associated with reduced mortality, but further studies are needed to provide robust evidence.

Discovery of novel PDE4 degraders with in vivo anti-inflammatory efficacy

Phosphodiesterase 4 (PDE4) has been identified to be an effective target for treatment of autoimmune and inflammatory diseases like chronic obstructive pulmonary disease (COPD), psoriasis and asthma. To overcome the selectivity problem, PDE4 degraders based on the proteolysis-targeting chimera (PROTAC) technology might be an alternative choose. Herein, a novel series of PDE4 PROTACs by recruiting Cereblon (CRBN) ligase were designed and synthesized. Among them, compound 9 m could suppress the secretion of pro-inflammatory cytokines such as TNF-α and IL-6 in LPS-stimulated Raw264.7 cells (IC50 = 43.25 μM, 53.79 μM). More importantly, 9 m could degrade PDE4B selectively (DC50 = 41.98 μM). Furthermore, we discovered that 9 m significantly reduced the infiltration of inflammatory cells into lung tissue to protect lung tissues and alleviate acute lung injury (ALI). Besides, 9 m exhibits moderate oral bioavailability (F%) of 21 %. Taken together, 9 m represents a novel PDE4 degrader deserving further development as a new lead compound for inflammatory diseases.

Incidence and risk factors of new clinical disorders in patients with COVID-19 hyperinflammatory syndrome

This study investigated new incident clinical disorders in patients with COVID-19-related hyperinflammatory syndrome (cHIS) 3.5 years post infection. We analyzed 14,335 patients hospitalized with COVID-19 from March-2020 to July-2023. cHIS was defined based on a point system that included elevated body temperature, macrophage activation, hematological dysfunction, coagulopathy, and hepatic enzyme. Outcomes were newly diagnosed disorders of hypertension, diabetes, cardiovascular diseases, chronic kidney disease (CKD), chronic obstructive pulmonary disease (COPD), and asthma post COVID-19. Cumulative incidences and hazard ratios were computed. Compared to non-cHIS patients, cHIS patients were older, fewer female, more Blacks, higher prevalence of pre-existing comorbidities. Patients with cHIS had higher risk of developing cardiovascular disease (HR = 1.24 [1.04,1.47] p < 0.05), CKD (1.24 [1.01, 1.53] p < 0.05), and obesity (1.61 [1.31,1.98], p < 0.001) but not hypertension, diabetes, COPD, and asthma. Cumulative incidence analysis showed that patients ≥ 50 years old showed markedly higher new incidences of individual new disorders compared to patients < 50 years old. COVID-19 related hyperinflammatory syndrome confers a significantly higher risk for developing new common clinical disorders. Identifying risks for developing new clinical disorders in patients with COVID-19 related hyperinflammatory syndrome may encourage diligent follow-up of high-risk individuals.

Inflammatory and Angiogenic Mediators Are Differentially Ex-Pressed in Patients with Post-COVID-19 Syndrome with Normal and Abnormal Spirometry Results

BACKGROUND

Inflammatory and angiogenic mediators play a key role in post-COVID-19 syndrome pathophysiology. These mediators might be of prognostic value for pulmonary function in this syndrome.

OBJECTIVES

To determine interleukin-6, -12, and -17, macrophage inflammatory protein-1A (MIP-1A), the vascular endothelial growth factor-A (VEGF-A) gene expression levels, the matrix metalloproteinase-9 (MMP-9) plasma levels, and the association of clinical data with pulmonary function in patients with post-COVID-19 syndrome with normal and abnormal spirometry results.

METHODS

Demographic/clinical data and blood samples were collected (45 patients). Pulmonary function was evaluated (spirometry), and the gene expression levels of inflammatory and angiogenic mediators (IL-6, IL-12, IL-17, MIP-1A, and VEGF-A) were determined in PBMCs (qPCR). MMP-9 plasma levels were determined (ELISA).

RESULTS

Seventeen out of forty-five patients with post-COVID-19 syndrome had abnormal spirometry values, which were associated with arterial hypertension, pneumonia, previous hospitalization, and disease severity (p < 0.05). IL-6, IL-12, and VEGF-A gene expression was upregulated in patients with post-COVID-19 syndrome compared with healthy controls. In patients with normal spirometry values, IL-17 and VEGF-A gene expression was upregulated (p < 0.05), but MIP-1A was downregulated (p < 0.05) (vs. the abnormal spirometry group). MMP-9 serum levels were increased in the normal spirometry group compared with the abnormal one (p < 0.05).

CONCLUSIONS

Post-COVID-19 syndrome has a complex immune pathophysiology, but potential inflammatory and angiogenic biomarkers, such as IL-6, IL-12, IL-17, MIP-1A, and VEGF-A, are differentially expressed in this syndrome and might be prognostic predictors of post-COVID-19 syndrome associated with pulmonary function alterations.

Iguratimod, a promising therapeutic agent for COVID-19 that attenuates excessive inflammation in mouse models

In severe COVID-19 patients, excessive inflammation can lead to multiorgan dysfunction. Current anti-inflammatory treatments like glucocorticoids partially improve the outcomes, while immune systems are compromised. We have identified that SARS-CoV-2-infected obese mice were a good model of the cytokine storm seen in COVID-19. Here, we revealed that iguratimod (IGU), an approved agent for rheumatoid arthritis, improved survival by attenuating inflammation with minimal immune suppression. In this study, C57BL/6 mice were fed a high-fat diet (HFD) or a normal-fat diet (NFD) for ten weeks before being infected with a mouse-adapted SARS-CoV-2. IGU significantly improved survival rates and reduced lung inflammation in HFD-fed mice, with minimal impact on interferon-induced genes and viral load. Meanwhile, dexamethasone (DEX) did not improve survival, while it suppressed various immune reactions with different mechanisms to IGU. Interestingly, IGU-treated mice had fewer SARS-CoV-2 positive cells in the lung, although viral replication was comparable to the control mice. Neither IGU nor DEX inhibited the SARS-CoV-2 infection in Vero-E6 cells, unlike the antiviral agent, remdesivir. Of note, IGU was effective prophylactically and therapeutically in HFD mice, and showed beneficial effects in NFD-fed mice with a lethal dose exposure of SARS-CoV-2. We demonstrated that IGU could be a promising treatment for severe COVID-19, especially in obese patients, by fine-tuning inflammation without compromising antiviral immunity. This study supports the possibility of drug repositioning for IGU COVID-19 beyond autoimmune diseases.

In-house assays for detecting anti-SARS-CoV-2 antibodies in serum and urine: Correlation with COVID-19 severity from a cohort study in Qatar

BACKGROUND

Serological assays targeting antibodies against key viral proteins, including the Spike (S1), Receptor Binding Domain (RBD), and Nucleocapsid, play a critical role in understanding immunity and supporting diagnostic efforts during COVID-19 pandemic, and afterward. This study aimed to develop and validate in-house assays for detecting anti-SARS-CoV-2 antibodies in serum and urine.

METHODS

ELISA-based assay was developed to detect IgG and IgM antibodies against SARS-CoV-2. The assay was examined in serum and urine samples of two different cohort of patients affected by COVID-19 disease with different severity and compared to age and sex matched control group. Neutralizing antibody activity was evaluated using an RBD-ACE2 binding inhibition assay. Additionally, a Sengenics protein microarray platform was employed to assess epitope-specific antibody responses.

RESULTS

The in-house ELISA assay reliably detected antibodies in both 163 serum and 64 urine samples compared to 50 serum samples from healthy control, with strong correlations observed between antibody levels in the two biofluids. Neutralizing antibody levels correlated positively with disease severity, highlighting their clinical relevance. The performance of the in-house assays was comparable to commercial kits, and the Sengenics microarray provided detailed insights into antibody profiles, identifying dominant epitopes within the Nucleocapsid core domain and RBD.

CONCLUSIONS

The developed in-house assay demonstrated robust performance and versatility, offering a cost-effective and scalable alternative to commercial kits. Their ability to detect antibodies in both serum and urine highlighted their potential as non-invasive diagnostic tools. These findings contribute to advancing sero-diagnostic capabilities, improving understanding of immune responses to SARS-CoV-2, and supporting global efforts to monitor and manage COVID-19 effectively.

Membrane Protein of SARS-CoV-2 Promotes the Production of CXCL10 and Apoptosis of Myocardial Cells

SARS-CoV-2 infections directly or indirectly cause unconscionable vascular events, significantly increasing the morbidity and mortality of COVID-19. Biomarkers associated with cardiac injury often elevate in individuals with COVID-19. Cytokine storm is a mechanism underlying myocardial cell injury caused by SARS-CoV-2 infections. Cell apoptosis in AC16 cells overexpressing structural and helper proteins of SARS-CoV-2 was detected by Western blot, MTT and TUNEL assay. The M protein was determined to play the most pronounced role in inducing apoptosis. Transcriptome sequencing on AC16 cells overexpressing the M protein was performed to screen differentially expressed genes (DEGs), which were further subjected to the gene set enrichment analysis. The regulatory effect of CXCL10 on cell apoptosis of AC16 cells overexpressing M protein was finally explored. Overexpression of M protein significantly increased the Bax/Bcl-2 and cleaved caspase-3/caspase-3(CC3/C3) ratios and the percentage of TUNEL-positive cells in AC16 cells, while markedly reducing cell viability. CXCL10 was the most prominent DEG in AC16 cells overexpressing M protein. Knockdown of CXCL10 partially reversed the increases in the Bax/Bcl-2 and cleaved caspase-3/caspase-3 ratios, the percentage of TUNEL-positive cells, as well as the release of pro-inflammatory cytokines in AC16 cells overexpressing M protein. The M protein of SARS-CoV-2 triggers the production of CXCL10 and apoptosis of myocardial cells.

NETosis: A key player in autoimmunity, COVID-19, and long COVID

NETosis, the process through which neutrophils release neutrophil extracellular traps (NETs), has emerged as a crucial mechanism in host defense and the pathogenesis of autoimmune responses. During the SARS-CoV-2 pandemic, this process received significant attention due to the central role of neutrophil recruitment and activation in infection control. However, elevated neutrophil levels and dysregulated NET formation have been linked to coagulopathy and endothelial damage, correlating with disease severity and poor prognosis in COVID-19. Moreover, it is known that SARS-CoV-2 can induce persistent low-grade systemic inflammation, known as long COVID, although the underlying causes remain unclear. It has been increasingly acknowledged that excessive NETosis and NET generation contribute to further pathophysiological abnormalities following SARS-CoV-2 infection. This review provides an updated overview of the role of NETosis in autoimmune diseases, but also the relationship between COVID-19 and long COVID with autoimmunity (e.g., latent and overt autoimmunity, molecular mimicry, epitope spreading) and NETosis (e.g., immune responses, NET markers). Finally, we discuss potential therapeutic strategies targeting dysregulated NETosis to mitigate the severe complications of COVID-19 and long COVID.

Molecular docking of polyphenol compounds and exploring the anticoagulant activity of Costus speciosus extracts in vitro and in vivo

Anticoagulants have an important role in the prevention of cardiovascular disorders. Costus speciosus (Costaceae) is a medicinal herb used to treat COVID-19-induced thrombosis. The purpose of this study was to assess the anticoagulant activity of various C. speciosus aqueous (CSAE), ethanol (SCEE), and methanol (CSME) extracts in vivo and in vitro utilizing thrombin time (TT), activated partial thromboplastin time (aPTT), and prothrombin time (PT). Different concentrations of the three extracts were used to evaluate the anticoagulation effects in vitro. In the in vivo assay, male Sprague Dawley rats were used to test the CSME as in vivo anticoagulants. Three groups of rats included the control group and the groups that received CSME daily at a low (200 mg/kg) or high dose (400 mg/kg b.w) for 2 weeks. The molecular docking of the major bioactive constituents of the methanolic extract against the binding site of the thrombin inhibitor complex was evaluated. The HPLC detected 13, 10 and 11 polyphenols in the methanolic, ethanolic and aqueous extracts, respectively. The in vitro results showed that all the studied extracts had anticoagulant activity and increased aPTT, TT, and PT time. The in vivo experiment supported the in vitro results and demonstrated that CSME greatly prolonged the anticoagulant characteristics when compared to the negative control. Both findings suggested that these extracts have significant anticoagulant activity, with CSME being more effective and potentially useful in pharmaceutical applications as a natural anticoagulant medication.

Defining diverse spike-receptor interactions involved in SARS-CoV-2 entry: Mechanisms and therapeutic opportunities

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is an enveloped RNA virus that caused the Coronavirus Disease 2019 (COVID-19) pandemic. The SARS-CoV-2 Spike glycoprotein binds to angiotensin converting enzyme 2 (ACE2) on host cells to facilitate viral entry. However, the presence of SARS-CoV-2 in nearly all human organs - including those with little or no ACE2 expression - suggests the involvement of alternative receptors. Recent studies have identified several cellular proteins and molecules that influence SARS-CoV-2 entry through ACE2-dependent, ACE2-independent, or inhibitory mechanisms. In this review, we explore how these alternative receptors were identified, their expression patterns and roles in viral entry, and their impact on SARS-CoV-2 infection. Additionally, we discuss therapeutic strategies aimed at disrupting these virus-receptor interactions to mitigate COVID-19 pathogenesis.

NLRP3 inflammasome: From drug target to drug discovery

The immune system employs innate and adaptive immunity to combat pathogens and stress stimuli. Innate immunity rapidly detects pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs) via pattern recognition receptors (PRRs), whereas adaptive immunity mediates antigen-specific T/B cell responses. The NLRP3 inflammasome, a key cytoplasmic PRR, consists of leucine-rich repeat, nucleotide-binding, and pyrin domains. Its activation requires priming (signal 1: Toll-like receptors/NOD-like receptors/cytokine receptors) and activation (signal 2: PAMPs/DAMPs/particulates). NLRP3 triggers cytokine storms and neuroinflammation, contributing to inflammatory diseases. Emerging therapies target NLRP3 via nuclear receptors (transcriptional regulation), adeno-associated virus (AAV) vectors (gene delivery), and microRNAs (post-transcriptional modulation). This review highlights NLRP3's signaling cascade, pathological roles, and combinatorial treatments leveraging nuclear receptors, AAVs, and microRNAs for immunomodulation.

Dynamic Molecular Changes in Brain, Lung, and Heart of Hamsters Infected With SARS-CoV-2: Insights From a Severe and Recovery Phase Model

The Global pandemic of coronavirus disease 2019 was initiated by the emergence of severe acute respiratory syndrome coronavirus 2. In addition to conventional pulmonary lesions, a range of neurological injury symptoms have been identified in clinical practice, but the aetiology of neurological disorders linked to SARS-CoV-2 infection remains poorly understood. Syrian hamsters, which are highly susceptible to SARS-CoV-2 infection, exhibit a disease phenotype similar to that observed in human COVID-19 patients. In this study, a hamster model of COVID-19 infection was used to analyze molecular changes in different tissues at various time points post infection with distinct strains using proteomic and phosphoproteomic approaches. Multi-omics analysis showed that SARS-COV-2 infection triggers sustained downregulation of the abundance and phosphorylation levels of neuronal and synapse-associated proteins in the brain, suggesting that neuronal damage persists even during the recovery period. Additionally, infections with SARS-CoV-2 may contribute to the onset of long-term symptoms of COVID-19 by impacting energy metabolism, neurotransmitter release, and synaptic transmission pathways. This study provides a comprehensive molecular profile of hamsters infected with different SARS-CoV-2 strains in different tissues, offering foundational insights into the pathogenic mechanisms of COVID-19.

Intestinal microbiota and respiratory system diseases: Relationships with three common respiratory virus infections

In recent years, the role of the intestinal microbiota in regulating host health and immune balance has attracted widespread attention. This study provides an in-depth analysis of the close relationship between the intestinal microbiota and respiratory system diseases, with a focus on three common respiratory virus infections, including respiratory syncytial virus (RSV), severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and influenza virus. The research indicates that during RSV infection, there is a significant decrease in intestinal microbial diversity, suggesting the impact of the virus on the intestinal ecosystem. In SARS-CoV-2 infection, there are evident alterations in the intestinal microbiota, which are positively correlated with the severity of the disease. Similarly, influenza virus infection is associated with dysbiosis of the intestinal microbiota, and studies have shown that the application of specific probiotics exhibits beneficial effects against influenza virus infection. Further research indicates that the intestinal microbiota exerts a wide and profound impact on the occurrence and development of respiratory system diseases through various mechanisms, including modulation of the immune system and production of short-chain fatty acids (SCFAs). This article comprehensively analyzes these research advances, providing new perspectives and potential strategies for the prevention and treatment of future respiratory system diseases. This study not only deepens our understanding of the relationship between the intestinal microbiota and respiratory system diseases but also offers valuable insights for further exploring the role of host-microbiota interactions in the development of diseases.

Long-term functional prognosis with tocilizumab in severe COVID-19 infection: A multicenter prospective observational study on mechanically ventilated ICU patients in the COVID-19 recovery study II

BACKGROUND

Tocilizumab, an IL-6 receptor antagonist, may prevent functional impairments in critically ill patients by attenuating the cytokine storm. This study investigated a potential effect of tocilizumab on preventing functional impairments in patients with severe coronavirus infection 2019 (COVID-19).

METHODS

In a multicenter prospective observational study, patients with COVID-19 ≥ 20 years requiring mechanical ventilation admitted to the intensive care unit between April 2021 and September 2021 and discharged alive were followed for one year. A self-administered questionnaire on sequelae and functional impairments was mailed in August 2022, and data were collected. A multivariate logistic regression was used to assess the impact of tocilizumab on physical function, mental health, and Long COVID.

RESULTS

Of 157 analyzed patients, 41 received tocilizumab. The tocilizumab group had more severe illness, but a lower prevalence of physical impairment (17.1 % vs. 23.3 %, p = 0.41) and mental disorders (19.5 % vs. 39.7 %, p = 0.009) than the non-tocilizumab group. The prevalence of Long COVID was higher in the tocilizumab group (92.7 % vs. 80.2 %, p = 0.06), whereas fatigue/malaise was significantly lower (19.5 % vs. 37.1 %, p = 0.039). Adjusted odds ratios (95 % confidence interval) for physical impairment, mental disorders, and Long COVID with tocilizumab were 0.70 (0.2-2.1), 0.40 (0.16-1.01), and 2.94 (0.7-12.3), respectively, with no significant difference.

CONCLUSIONS

Tocilizumab was associated with a lower prevalence of physical impairment and mental disorders at 1 year in patients with severe COVID-19. Furthermore, Long COVID had a weaker impact on physical and cognitive functions.

Machine Learning Accurately Predicts Need for Critical Care Support in Patients Admitted to Hospital for Community-Acquired Pneumonia

OBJECTIVES

Hospitalized community-acquired pneumonia (CAP) patients are admitted for ventilation, vasopressors, and renal replacement therapy (RRT). This study aimed to develop a machine learning (ML) model that predicts the need for such interventions and compare its accuracy to that of logistic regression (LR).

DESIGN

This retrospective observational study trained separate models using random-forest classifier (RFC), support vector machines (SVMs), Extreme Gradient Boosting (XGBoost), and multilayer perceptron (MLP) to predict three endpoints: eventual use of invasive ventilation, vasopressors, and RRT during hospitalization. RFC-based models were overall most accurate in a derivation COVID-19 CAP cohort and were validated in one COVID-19 CAP and two non-COVID-19 CAP cohorts.

SETTING

This study is part of the Community-Acquired Pneumonia: Toward InnoVAtive Treatment (CAPTIVATE) Research program.

PATIENTS

Two thousand four hundred twenty COVID-19 and 1909 non-COVID-19 CAP patients over 18 years old hospitalized and not needing invasive ventilation, vasopressors, and RRT on the day of admission were included.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Performance was evaluated with area under the receiver operating characteristic curve (AUROC) and accuracy. RFCs performed better than XGBoost, SVM, and MLP models. For comparison, we evaluated LR models in the same cohorts. AUROC was very high ranging from 0.74 to 0.95 in predicting ventilation, vasopressors, and RRT use in our derivation and validation cohorts. ML used and variables such as Fio2, Glasgow Coma Scale, and mean arterial pressure to predict ventilator, vasopressor use, creatinine, and potassium to predict RRT use. LR was less accurate than ML, with AUROC ranging 0.66 to 0.8.

CONCLUSIONS

A ML algorithm more accurately predicts need of invasive ventilation, vasopressors, or RRT in hospitalized non-COVID-19 CAP and COVID-19 patients than regression models and could augment clinician judgment for triage and care of hospitalized CAP patients.

Ferritin's role in infectious diseases: Exploring pathogenic mechanisms and clinical implications

Ferritin, an iron storage protein, is crucial for maintaining iron metabolism balance throughout the body and serves as a key biomarker for evaluating the body's iron reserves. Reduced ferritin levels typically indicate iron deficiency, whereas elevated ferritin levels indicate an acute inflammatory response in infectious diseases. Recent research has established a significant link between elevated ferritin levels and disease severity and prognosis. The concept of hyperferritinemic syndrome has underscored ferritin's role as a pathogenic mediator. During infections, ferritin not only serves as a biomarker of inflammation but also exerts pro-inflammatory functions, which is a key factor in perpetuating the vicious pathogenic cycle. This review offers a comprehensive exploration of ferritin, covering its structural characteristics, regulatory mechanisms, and how diverse pathogens modulate ferritin. Understanding its pivotal role in infectious diseases is essential for identifying novel therapeutic prospects and enhancing disease management and prevention.

Effect of Bacillus Subtilis BN Strain on M1 Macrophage Antiviral Response

M1 macrophages play an important role in pathogenic microorganism infection. Natto, a traditional fermented food from Japan, has long been thought to prevent infection by pathogenic microorganisms. Bacillus subtilis BN strain, which has been isolated from natto, is used in animal feed, health food products, and pharmaceuticals as a probiotic capable of regulating intestinal flora and immunomodulates. The purpose of this study is to investigate the effects of B. subtilis BN strain on the antiviral immune function of human M1 macrophages. The M1 macrophages studied here were derived from a human monocytic cell line (THP-1). Overall, we found that B. subtilis BN strain enhanced gene expressions of antiviral and anti-inflammatory cytokines in M1 macrophages and M1 macrophages stimulated with resiquimod in a cell culture model that mimics single-stranded RNA virus infection. In M1 macrophages, B. subtilis BN strain was also found to promote the gene expression and phosphorylation of key molecules in the toll-like receptor signaling pathways. Furthermore, the BN strain induced the expression of some cytokine mRNA was reduced by the knockdown of NFκB in M1 macrophages. Taken together, these results suggest that toll-like receptor signal pathways are involved in the regulation of antiviral and anti-inflammatory cytokine gene expressions induced by the BN strain in M1 macrophages.

Postpartum hemorrhage emerges as a key outcome of maternal SARS-CoV-2 omicron variant infection surge across pregnancy trimesters

BACKGROUND

Despite evidence showing changes in disease severity with the virus's evolution and vaccination efforts, the link between maternal, perinatal, and neonatal outcomes and SARS-CoV-2 infections during different pregnancy trimesters remains unclear, especially with the BA.5 and BF.7 Omicron subvariant surge in China in December 2022. This study investigates the correlation between maternal, perinatal, and neonatal outcomes and SARS-CoV-2 infection across various pregnancy trimesters.

METHODS

This prospective cohort study was conducted at two hospitals in southwest China, examining the clinical records and infection status of 2158 pregnant women registered between January 1, 2022, and September 30, 2023. Initially shielded from COVID-19, the population later experienced a significant infection surge. A comparative analysis evaluated maternal, perinatal, and neonatal outcomes between infected and uninfected subjects. Primary outcomes included pregnancy complications and premature births, while secondary outcomes encompassed cesarean sections, delivery complications, and neonatal outcomes.

RESULTS

Pregnant women infected with SARS-CoV-2 had higher incidence of placenta increta/percreta and postpartum hemorrhage compared to uninfected women. First trimester infections were associated with a lower incidence of intrahepatic cholestasis of pregnancy [aOR = 0.29, 95 % CI 0.13-0.63] but a higher incidence of preterm birth [aOR = 2.16, 95 % CI 1.25-3.71]. Third trimester infections increased the risk of postpartum hemorrhage [aOR = 2.74, 95 % CI 1.21-6.18].

CONCLUSION

SARS-CoV-2 infection during pregnancy is linked to increased incidence of placenta increta/percreta and postpartum hemorrhage. First trimester infections are associated with higher incidence of premature birth and lower incidence of intrahepatic cholestasis of pregnancy, while third trimester infections are linked to higher incidence of postpartum hemorrhage.

Organs on chips: fundamentals, bioengineering and applications

Human body constitutes unique biological system containing specific fluid mechanics and biomechanics. Traditional cell culture techniques of 2D and 3D do not recapitulate these specific natures of the human system. In addition, they lack the spatiotemporal conditions of representing the cells. Moreover, they do not enable the study of cell-cell interactions in multiple cell culture platforms. Therefore, establishing biological system of dynamic cell culture was of great interest. Organs on chips systems were fabricated proving their concept to mimic specific organs functions. Therefore, it paves the way for validating new drugs and establishes mechanisms of emerging diseases. It has played a key role in validating suitable vaccines for Coronavirus disease (COVID-19). Herein, the concept of organs on chips, fabrication methodology and their applications are discussed.

Inflammatory and pulmonary function characteristics of bronchial asthma induced by COVID‑19 infection

Bronchial asthma, a widely prevalent respiratory disease influencing individuals of all age groups worldwide, has been increasingly recognized as a global concern. While there exists a potentially heightened risk of severe coronavirus disease 2019 (COVID-19) in asthmatic patients, particularly those with non-allergic asthma, it is uncertain whether COVID-19 infection-induced bronchial asthma has its own unique clinical characteristics. The present study aimed to compare and analyze the pulmonary function and eosinophilic inflammation indices of patients with COVID-19 infection-induced bronchial asthma and those with typical bronchial asthma, and further deepen the understanding of COVID-19 infection-induced bronchial asthma. A retrospective analysis was conducted on the pulmonary function and inflammatory characteristics of 116 patients diagnosed with COVID-19 infection-induced bronchial asthma and treated in outpatient clinics after March 2023, as well as 113 patients with typical bronchial asthma diagnosed and treated from January 2022 to November 2022. The main clinical characteristics were cough, sputum, chest tightness, dyspnea and wheezing. There was no significant difference in clinical characteristics between the two groups. The results indicated that there was no significant difference in the total IgE, the absolute value and percentage of eosinophil, transoral FeNO, and trans-nasal FeNO in the peripheral blood samples of patients in the COVID-19 infection-induced bronchial asthma group compared with the typical bronchial asthma group. Although there was no significant difference between the two groups in the rates of impairment in ventilation function, reserve function, and small airway function, significant differences were identified in various indicators, including forced expiratory volume in 1 sec as a percentage of the predicted value (FEV1%), residual volume/total lung capacity (RV/TLC), peak expiratory flow (PEF), maximal expiratory flow rate at 75% (MEF75), maximal voluntary ventilation (MVV), FEV * 30, and residual volume (RV) between the two groups. The findings indicated that patients with COVID-19 infection-induced bronchial asthma exhibited a comparatively inferior pulmonary function versus those with typical bronchial asthma. However, it is important to note that the clinical impact of this disparity was not statistically significant.

Predictive models of severe disease in patients with COVID-19 pneumonia at an early stage on CT images using topological properties

Prediction of severe disease (SVD) in patients with coronavirus disease (COVID-19) pneumonia at an early stage could allow for more appropriate triage and improve patient prognosis. Moreover, the visualization of the topological properties of COVID-19 pneumonia could help clinical physicians describe the reasons for their decisions. We aimed to construct predictive models of SVD in patients with COVID-19 pneumonia at an early stage on computed tomography (CT) images using SVD-specific features that can be visualized on accumulated Betti number (BN) maps. BN maps (b0 and b1 maps) were generated by calculating the BNs within a shifting kernel in a manner similar to a convolution. Accumulated BN maps were constructed by summing BN maps (b0 and b1 maps) derived from a range of multiple-threshold values. Topological features were computed as intrinsic topological properties of COVID-19 pneumonia from the accumulated BN maps. Predictive models of SVD were constructed with two feature selection methods and three machine learning models using nested fivefold cross-validation. The proposed model achieved an area under the receiver-operating characteristic curve of 0.854 and a sensitivity of 0.908 in a test fold. These results suggested that topological image features could characterize COVID-19 pneumonia at an early stage as SVD.

Cytokine immune profiles among COVID 19 patients with different disease severities seeking treatment at Moi teaching and referral hospital, Kenya

BACKGROUND

COVID-19 manifests with a wide range of severities, from asymptomatic to critical conditions. Immunological profiles in patients positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may serve as early indicators of disease severity, aiding in prioritizing patient care.

METHODOLOGY

Archived patient plasma samples were retrieved from the Molecular Lab Bio-repository, ensuring equal representation of males, females, and various disease severities. Socio-demographic and disease severity data were obtained from patient health records. Levels of pro-inflammatory cytokines (interferon-gamma [IFN-γ], tumor necrosis factor-alpha [TNF-α], interleukin-2 [IL-2], and interleukin-17 [IL-17]) and anti-inflammatory cytokines (interleukin-4 [IL-4], interleukin-6 [IL-6], and interleukin-10 [IL-10]) were measured using the BD FACSCalibur flow cytometer. Data analysis involved comparing cytokine levels across different disease severities, with demographic data expressed as means ± standard deviation (SD). Statistical significance was set at P ≤ 0.05.

FINDINGS

The mean ages for males and females were 49.6 ± 22.7 and 48.4 ± 23.7, respectively. Mean ages for disease severity categories were 33 ± 19 (asymptomatic), 45.2 ± 21.5 (moderate), 56.8 ± 18.7 (severe), and 61.95 ± 22 (critical). Comorbidities were present in 25 % of patients, with cardiovascular disease (41 %) and pulmonary disease (31 %) being the most common. Predominant symptoms in critical patients included dyspnea (63 %) and myalgia (60 %), while rhinorrhea (46.2 %) and chest pain (45.7 %) were common in severe cases. Gastrointestinal symptoms were observed only in severe and critical groups. Levels of the pro-inflammatory cytokines (IFN-γ, TNF-α, and IL-17) increased linearly with disease severity. Among anti-inflammatory cytokines, IL-6 and IL-10 levels also rose significantly with increasing severity.

CONCLUSION

Levels of TNF-α, IL-17, and IL-6 correlated with disease severity and may serve as prognostic biomarkers. Advanced age and underlying comorbidities were independently associated with higher disease severity.

A detailed examination of coronavirus disease 2019 (COVID-19): Covering past and future perspectives

The COVID-19 disease has spread rapidly across the world within just six months, affecting 169 million people and causing 3.5 million deaths globally (2021). The most affected countries include the USA, Brazil, India, and several European countries such as the UK and Russia. Healthcare professionals face new challenges in finding better ways to manage patients and save lives. In this regard, more comprehensive research is needed, including genomic and proteomic studies, personalized medicines and the design of suitable treatments. However, finding novel molecular entities (NME) using a standard or de novo strategy to drug development is a time-consuming and costly process. Another alternate strategy is discovering new therapeutic uses for old/existing/available medications, known as drug repurposing. There are a variety of computational repurposing methodologies, and some of them have been used to counter the coronavirus disease pandemic of 2019 (COVID-19). This review article compiles recently published data on the origin, transmission, pathogenesis, diagnosis, and management of the coronavirus by drug repurposing and vaccine development approach. We have attempted to screen probable drugs in clinical trials by using literature survey. This systematic review aims to create priorities for future research of drugs repurposed and vaccine development for COVID-19.

A Gene Cluster of Mitochondrial Complexes Contributes to the Cognitive Decline of COVID-19 Infection

"Brain fog," a persistent cognitive impairment syndrome, stands out as a significant neurological aftermath of coronavirus disease 2019 (COVID-19). Yet, the underlying mechanisms by which COVID-19 induces cognitive deficits remain elusive. In our study, we observed an upregulation in the expression of genes linked to the inflammatory response and oxidative stress, whereas genes associated with cognitive function were downregulated in the brains of patients infected with COVID-19. Through single-nucleus RNA sequencing (snRNA-seq) analysis, we found that COVID-19 infection triggers the immune responses in microglia and astrocytes and exacerbates oxidative stress in oligodendrocytes, oligodendrocyte progenitors (OPCs), and neurons. Further investigations revealed that COVID-19 infection elevates LUC7L2 expression, which inhibits mitochondrial oxidative phosphorylation (OXPHOS) and suppresses the expression of mitochondrial complex genes such as MT-ND1, MT-ND2, MT-ND3, MT-ND4L, MT-CYB, MT-CO3, and MT-ATP6. A holistic approach to protect mitochondrial complex function, rather than targeting a single molecular, should be an effective therapeutic strategy to prevent and treat the long-term consequences of "long COVID."

Plasma SARS-CoV-2 nucleocapsid antigen levels are associated with lung infection and tissue-damage biomarkers

BACKGROUND

SARS-CoV-2 nucleocapsid (N) antigen has been confirmed in the peripheral blood of patients with new coronavirus infection,yet its diagnostic and prognostic significance remains unclear. This study aimed to characterize the dynamics of SARS-CoV-2 N antigenemia in patients with novel coronavirus positivity, and to assess its potential association with clinical severity and plasma biomarker levels.

METHODS

We analyzed the level of SARS-CoV-2 N antigen, spike receptor-binding domain (S-RBD) IgG, neutralizing antibodies (NAb) and tissue-damage biomarkers was assessed in 180 plasma samples from 51 SARS-CoV-2-positive individuals. Plasma antigen levels were compared with concurrent respiratory nucleic acid amplification test results.

RESULTS

Patients with Ct values below 30 showed significantly different serum antigen levels compared to those with Ct values above 30 (p < 0.01). However, no significant positive correlation was found between respiratory viral load and serum antigen levels. Further analysis revealed that patients with pneumonia had markedly higher serum antigen levels than those without (p < 0.0001). Additionally, serum amyloid A (SAA) and ferritin (Fe) levels were significantly elevated in the antigenemia-positive group compared to the negative group, while procalcitonin (PCT) and interleukin-6 (IL-6) levels showed no significant differences. Notably, the positivity rate of N antigen in peripheral blood peaked at 47.1% (95% CI: 37.8%-56.7%) during the first week of infection and then gradually decreased over time. Moreover, patients with severe COVID-19 exhibited significantly higher serum antigen levels than those with mild or moderate disease (p < 0.0001). Serum levels of SARS-CoV-2 S-RBD IgG and neutralizing antibodies (NAb) were also significantly higher in antigenemia-negative patients than in antigenemia-positive patients (p < 0.0001).

CONCLUSIONS

Our findings highlight the multifaceted role of antigenemia in SARS-CoV-2 and suggest its potential as a biomarker for disease monitoring and risk stratification.

Early suPAR levels as a predictor of COVID-19 severity: A new tool for efficient patient triage

BACKGROUND

Following several waves of the COVID-19 pandemic, we are now facing a lower but persistent rate of SARS-CoV-2 infections, with seasonal resurgences often coinciding with other respiratory tract infections.

OBJECTIVE

We aimed to identify early clinico-biological variables predictive of an unfavorable outcome in patients with primary SARS-CoV-2 infection. We also evaluated the role of suPAR, an innovative biomarker, in predicting disease severity.

METHODS

We included 255 patients with PCR-confirmed primary SARS-CoV-2 infection and with a 30-day follow-up minimum. Blood samples were collected within the first 24 h of hospitalization to measure suPAR levels. Comprehensive data from medical records were analyzed to assess their predictive value in stratifying patients into seven severity groups, with groups 1 to 3 representing severe COVID-19 (death, intubation, ECMO, or non-invasive ventilation).

RESULTS

Early plasma suPAR levels were significantly associated with severe disease progression, as evidenced by ANOVA and logistic regression models, highlighting suPAR as a persistent predictive factor for unfavorable outcomes.

CONCLUSION

Our findings suggest that a single suPAR measurement, performed early after a positive PCR test for SARS-CoV-2, holds strong predictive value for patient outcomes. This biomarker, alongside pulse oximetry and CT scan results, could be instrumental in early patient triage during seasonal COVID-19 resurgences.

Semi-Markov Multistate Modeling Approaches for Multicohort Event History Data

Two Cox-based multistate modeling approaches are compared for modeling a complex multicohort event history process. The first approach incorporates cohort information as a fixed covariate, thereby providing a direct estimation of the cohort-specific effects. The second approach includes the cohort as a stratum variable, which offers an extra flexibility in estimating the transition probabilities. Additionally, both approaches may include possible interaction terms between the cohort and a given prognostic predictor. Furthermore, the Markov property conditional on observed prognostic covariates is assessed using a global score test. Whenever departures from the Markovian assumption are revealed for a given transition, the time of entry into the current state is incorporated as a fixed covariate, yielding a semi-Markov process. The two proposed methods are applied to a three-wave dataset of COVID-19-hospitalized adults in the southern Barcelona metropolitan area (Spain), and the corresponding performance is discussed. While both semi-Markovian approaches are shown to be useful, the preferred one will depend on the focus of the inference. To summarize, the cohort-covariate approach enables an insightful discussion on the behavior of the cohort effects, whereas the stratum-cohort approach provides flexibility to estimate transition-specific underlying risks according to the different cohorts.

Association Between Genetic Variants in TNF, IL6, and IL1B Genes and Severity of COVID-19: A Cross-Sectional Study of Patients from Southern Brazil

Background/Objectives: Genetic variants in cytokine genes such as IL1B, IL6, and TNF may influence inflammatory responses to SARS-CoV-2 and affect disease severity. This study investigates the role of these variants in relation to COVID-19 outcomes, including hospitalization, ICU admission, and mortality. Methods: A total of 500 unvaccinated individuals from southern Brazil diagnosed with COVID-19 via RT-PCR were analyzed. DNA was extracted from nasopharyngeal swabs and genotyped for functional variants selected based on evidence of regulatory function and prior associations with inflammatory outcomes-IL1B (rs4848306, rs1143623, rs16944, rs1143627), IL6 (rs1800795, rs2069832, rs2069840, rs2069845), and TNF (rs1799964, rs1800630, rs1799724, rs1800629, rs361525). Multivariate logistic regression analysis, adjusted for sex and age, was employed to assess the association between these genetic variants and severe clinical outcomes. Results: The results indicated that the IL1B rs16944-AG (OR: 1.98 [95% CI: 1.22-3.23], p = 0.006) and TNF rs1799964-CT (OR: 1.97 [95% CI: 1.22-3.22], p = 0.006) genotypes were associated with the need for hospitalization, while TNF rs1800630-AA (OR: 2.37 [95% CI: 1.08-5.33], p = 0.034) was associated with ICU admission. Additionally, the CC genotype of TNF rs1799964 was associated with a higher risk of mortality (OR: 3.73 [95% CI: 1.21-14.37], p = 0.034). Conclusions: Genetic variants-specifically IL1B rs16944 and rs1143627, and TNF rs1799964 and rs1800630-were associated with COVID-19 severity and should be further investigated in larger studies to evaluate their potential as predictive markers of severe outcomes in COVID-19.

Anti-Inflammatory and Immunomodulatory Effects of Intravenous Lidocaine in Surgery: A Narrative Review

Lidocaine, a widely used local anaesthetic, has been shown to possess anti-inflammatory and immunomodulatory properties with applications in surgery. During a surgical procedure, inflammation is a natural response of the body, triggered by the release of inflammatory mediators and the activation of the immune system. However, an excessive response can lead to serious postoperative complications. Lidocaine modulates inflammation through mechanisms beyond its anaesthetic action. It reduces the activation of neutrophils and macrophages, decreases the release of pro-inflammatory cytokines and prostaglandins, and preserves endothelial integrity, helping to control excessive inflammatory responses. Additionally, its perioperative use has shown benefits such as reduced postoperative pain, lower opioid consumption, and faster intestinal recovery. Furthermore, studies have suggested that lidocaine may have an anti-metastatic effect by inhibiting the migration of tumour cells and the activation of inflammatory pathways related to cancer spread. Although its use in surgery is promising, further research is needed to determine optimal dosages and its long-term clinical impact.

Efficacy and safety of acalabrutinib with best supportive care versus best supportive care in patients with COVID-19 requiring hospitalization

The efficacy and safety of acalabrutinib, a Bruton tyrosine kinase (BTK) inhibitor, was evaluated in 2 phase 2 studies in hospitalized patients with coronavirus disease 2019 (COVID-19) who received acalabrutinib + best supportive care (BSC) versus BSC alone (Clinicaltrials.gov: NCT04380688 and NCT04346199). The primary endpoint was the percentage of patients alive and free of respiratory failure on day 14 (rest of the world [RoW] study) and day 28 (US study). In the RoW study, 177 patients were randomized (acalabrutinib + BSC: n = 89; BSC: n = 88); in the US study, 62 patients were randomized (acalabrutinib + BSC: n = 31; BSC: n = 31). The percentage of patients who met the primary endpoint was similar in both studies (RoW study: acalabrutinib + BSC: 83.1%, BSC: 90.9%; US study: acalabrutinib + BSC: 80.6%, BSC: 83.9%). No new safety concerns were reported. Overall, no significant clinical benefit of adding acalabrutinib to BSC in patients hospitalized with COVID-19 was observed.

Hotspots and Trends in Research on Early Warning of Infectious Diseases: A Bibliometric Analysis Using CiteSpace

Background: Emerging and re-emerging infectious diseases (EIDs and Re-EIDs) cause significant economic crises and public health problems worldwide. Epidemics appear to be more frequent, complex, and harder to prevent. Early warning systems can significantly reduce outbreak response times, contributing to better patient outcomes. Improving early warning systems and methods might be one of the most effective responses. This study employs a bibliometric analysis to dissect the global research hotspots and evolutionary trends in the field of infectious disease early warning, with the aim of providing guidance for optimizing public health emergency management strategies. Methods: Publications related to the role of early warning systems in detecting and responding to infectious disease outbreaks from 1999 to 2024 were retrieved from the Web of Science Core Collection (WoSCC) database. CiteSpace software was used to analyze the datasets and generate knowledge visualization maps. Results: A total of 798 relevant publications are included. The number of annual publications has sharply increased since 2000. The USA produced the highest number of publications and established the most extensive cooperation relationships. The Chinese Center for Disease Control & Prevention was the most productive institution. Drake, John M was the most prolific author, while the World Health Organization and AHMED W were the most cited authors. The top two cited references mainly focused on wastewater surveillance of SARS-CoV-2. The most common keywords were "infectious disease", "outbreak", "transmission", "virus", and "climate change". The basic keyword "climate" ranked the first and long duration with the strongest citation burst. "SARS-CoV-2", "One Health", "early warning system", "artificial intelligence (AI)", and "wastewater-based epidemiology (WBE)" were emerging research foci. Conclusions: Over the past two decades, research on early warning of infectious diseases has focused on climate change, influenza, SARS, virus, machine learning, warning signals and systems, artificial intelligence, and so on. Current research hotspots include wastewater-based epidemiology, sewage, One Health, and artificial intelligence, as well as the early warning and monitoring of COVID-19. Research foci in this area have evolved from focusing on climate-disease interactions to pathogen monitoring systems, and ultimately to the "One Health" integrated framework. Our research findings underscore the imperative for public health policymakers to prioritize investments in real-time surveillance infrastructure, particularly wastewater-based epidemiology and AI-driven predictive models, and strengthen interdisciplinary collaboration frameworks under the One Health paradigm. Developing an integrated human-animal-environment monitoring system will serve as a critical development direction for early warning systems for epidemics.

Host susceptibilities and entry processes of SARS-CoV-2 Omicron variants using pseudotyped viruses carrying spike protein

The zoonotic potential has been well studied for SARS-CoV-2 and its earlier variants, but the information for Omicron variants and SARS-CoV is lacking. In this study, we generated lentivirus-based pseudoviruses carrying spike protein (S) of SARS-CoV-2, parental and Omicron variants including BA.1.1, BA.4/5, XBB.1 and JN.1 to assess the entry into cells expressing human or animal ACE2 including dogs, cats and white-tailed deer. Using these pseudoviruses, along with pseudoviruses carrying S of MERS-CoV and SARS-CoV, we assessed the protease processing of these various S through western blotting, entry/inhibition assays, and fusion assays. The results showed that overall, pseudotyped viruses carrying each S of SARS-CoV-2 Omicron strains efficiently entered cells expressing human or animal ACE2 comparably (BA.1.1 and JN.1) or better (BA.4/5 and XBB.1) than those with parental strain. In addition, the entries of pseudotyped viruses carrying S of SARS-CoV were also efficient the cells expressing human or animal ACE2. The presence of TMPRSS2 significantly increased the entry of all tested pseudoviruses including those with S of MERS-CoV, SARS-CoV and SARS-CoV-2, with BA.1.1, JN1, and XBB.1 Omicron having the largest fold increase. When cathepsin inhibitors were examined to assess their inhibitory effects on entry of parental and Omicron variants, they were significantly less effective in the entry of Omicron variants compared to parent strain, suggesting Omicron strains do not depend on the endosomal route compared to parental strain.