A randomised clinical trial of awake prone positioning in COVID-19 suspects with acute hypoxemic respiratory failure.

Background: Awake prone position (APP) has been reported to improve oxygenation in patients with COVID-19 disease and to reduce the requirement for invasive mechanical ventilation for patients requiring support with high flow nasal cannula. There is conflicting data for patients requiring lower-level oxygen support. Research question: Does APP reduce escalation of oxygen support in COVID-19 patients requiring supplementary oxygen?The primary outcome was defined as an escalation of oxygen support from simple supplementary oxygen (NP, HM, NRB) to NIV (CPAP or BiPAP), HFNC or IMV; OR from NIV (CPAP or BiPAP) or HFNC to IMV by day30. Study design: Two center, prospective, non-blind, randomised controlled trial. Patients with confirmed or suspected COVID-19 pneumonia requiring ≥ 5 liters/min oxygen to maintain saturations ≥ 94 % were randomised to either APP or control group. The APP group received a 3-h APP session three times per day for three days. Results: Between 9 May and July 13, 2021, 89 adults were screened and 61 enrolled, 31 to awake prone position and 30 controls. There was no difference in the primary outcome, 7 (22.6 %) patients randomised to APP and 9 (30.0 %) controls required escalation of oxygen support (OR 0.68 (0.22-2.14), P = 0.51). There were no differences in any secondary outcomes, in APP did not improve oxygenation. Interpretation: In COVID-19 patients, the use of APP did not prevent escalation of oxygen support from supplementary to invasive or non-invasive ventilation or improve patient respiratory physiology. Trial registration: NCT04853979 (clinicaltrials.gov).

SARS-CoV-2 infection triggers more potent antibody-dependent cellular cytotoxicity (ADCC) responses than mRNA-, vector-, and inactivated virus-based COVID-19 vaccines.

Neutralizing antibodies (NAbs) are elicited after infection and vaccination and have been well studied. However, their antibody-dependent cellular cytotoxicity (ADCC) functionality is still poorly characterized. Here, we investigated ADCC activity in convalescent sera from infected patients with wild-type (WT) severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) or omicron variant compared with three coronavirus disease 2019 (COVID-19) vaccine platforms and postvaccination breakthrough infection (BTI). We analyzed ADCC activity targeting SARS-CoV-2 spike (S) and nucleocapsid (N) proteins in convalescent sera following WT SARS-CoV-2-infection (n = 91), including symptomatic and asymptomatic infections, omicron-infection (n = 8), COVID-19 vaccination with messenger RNA- (mRNA)- (BNT162b2 or mRNA-1273, n = 77), adenovirus vector- (n = 41), and inactivated virus- (n = 46) based vaccines, as well as post-mRNA vaccination BTI caused by omicron (n = 28). Correlations between ADCC, binding, and NAb titers were reported. ADCC was elicited within the first month postinfection and -vaccination and remained detectable for ≥3 months. WT-infected symptomatic patients had higher S-specific ADCC levels than asymptomatic and vaccinated individuals. Also, no difference in N-specific ADCC activity was seen between symptomatic and asymptomatic patients, but the levels were higher than the inactivated vaccine. Notably, omicron infection showed reduced overall ADCC activity compared to WT SARS-CoV-2 infection. Although post-mRNA vaccination BTI elicited high levels of binding and NAbs, ADCC activity was significantly reduced. Also, there was no difference in ADCC levels across the four vaccines, although NAbs and binding antibody titers were significantly higher in mRNA-vaccinated individuals. All evaluated vaccine platforms are inferior in inducing ADCC compared to natural infection with WT SARS-CoV-2. The inactivated virus-based vaccine can induce N-specific ADCC activity, but its relevance to clinical outcomes requires further investigation. Our data suggest that ADCC could be used to estimate the extra-neutralization level against COVID-19 and provides evidence that vaccination should focus on other Fc-effector functions besides NAbs. Also, the decreased susceptibility of the omicron variant to ADCC offers valuable guidance for forthcoming efforts to identify the specific targets of antibodies facilitating ADCC.

Predicted deleterious variants in the human genome relevant to gene therapy with adeno-associated virus vectors.

Based on the observation that humans have variable responses of gene expression with the same dose of an adeno-associated vector, we hypothesized that there are deleterious variants in genes coding for processes required for adeno-associated virus (AAV)-mediated gene transfer/expression that may hamper or enhance the effectiveness of AAV-mediated gene therapy. To assess this hypothesis, we evaluated 69,442 whole genome sequences from three populations (European, African/African American, and Qatari) for predicted deleterious variants in 62 genes known to play a role in AAV-mediated gene transfer/expression. The analysis identified 5,564 potentially deleterious mutations of which 27 were classified as common based on an allele frequency ≥1% in at least one population studied. Many of these deleterious variants are predicated to prevent while others enhance effective AAV gene transfer/expression, and several are linked to known hereditary disorders. The data support the hypothesis that, like other drugs, human genetic variability contributes to the person-to-person effectiveness of AAV gene therapy and the screening for genetic variability should be considered as part of future clinical trials.

A CRISPR-based approach using dead Cas9-sgRNA to detect SARS-CoV-2.

Rapid, highly specific, and robust diagnostic kits to detect viruses and pathogens are needed to control disease spread and transmission globally. Of the many different methods proposed to diagnose COVID-19 infection, CRISPR-based detection of nucleic acids tests are among the most prominent. Here, we describe a new way of using CRISPR/Cas systems as a rapid and highly specific tool to detect the SARS-CoV-2 virus using the in vitro dCas9-sgRNA-based technique. As a proof of concept, we used a synthetic DNA of the M gene, one of the SARS-CoV-2 virus genes, and demonstrated that we can specifically inactivate unique restriction enzyme sites on this gene using CRISPR/Cas multiplexing of dCas9-sgRNA-BbsI and dCas9-sgRNA-XbaI. These complexes recognize and bind to the target sequence spanning the BbsI and XbaI restriction enzyme sites, respectively, and protect the M gene from digestion by BbsI and/or XbaI. We further demonstrated that this approach can be used to detect the M gene when expressed in human cells and from individuals infected with SARS-CoV-2. We refer to this approach as dead Cas9 Protects Restriction Enzyme Sites, and believe that it has the potential to be applied as a diagnostic tool for many DNA/RNA pathogens.

Assessment of Broadly Reactive Responses in Patients With MERS-CoV Infection and SARS-CoV-2 Vaccination.

Importance: In the ongoing COVID-19 pandemic, there remain unanswered questions regarding the nature and importance of the humoral immune response against other coronaviruses. Although coinfection of the Middle East respiratory syndrome coronavirus (MERS-CoV) with the SARS-CoV-2 has not been documented yet, several patients previously infected with MERS-CoV received the COVID-19 vaccine; data describing how preexisting MERS-CoV immunity may shape the response to SARS-CoV-2 following infection or vaccination are lacking. Objective: To characterize the cross-reactive and protective humoral responses in patients exposed to both MERS-CoV infection and SARS-CoV-2 vaccination. Design, Setting, and Participants: This cohort study involved a total of 18 sera samples collected from 14 patients with MERS-CoV infection before (n = 12) and after (n = 6) vaccination with 2 doses of COVID-19 mRNA vaccine (BNT162b2 or mRNA-1273). Of those patients, 4 had prevaccination and postvaccination samples. Antibody responses to SARS-CoV-2 and MERS-CoV were assessed as well as cross-reactive responses to other human coronaviruses. Main Outcomes and Measures: The main outcomes measured were binding antibody responses, neutralizing antibodies, and antibody-dependent cellular cytotoxicity (ADCC) activity. Binding antibodies targeting SARS-CoV-2 main antigens (spike [S], nucleocapsid, and receptor-binding domain) were detected using automated immunoassays. Cross-reactive antibodies with the S1 protein of SARS-CoV, MERS-CoV, and common human coronaviruses were analyzed using a bead-based assay. Neutralizing antibodies (NAbs) against MERS-CoV and SARS-CoV-2 as well as ADCC activity against SARS-CoV-2 were assessed. Results: A total of 18 samples were collected from 14 male patients with MERS-CoV infection (mean [SD] age, 43.8 [14.6] years). Median (IQR) duration between primary COVID-19 vaccination and sample collection was 146 (47-189) days. Prevaccination samples had high levels of anti-MERS S1 immunoglobin M (IgM) and IgG (reactivity index ranging from 0.80 to 54.7 for IgM and from 0.85 to 176.3 for IgG). Cross-reactive antibodies with SARS-CoV and SARS-CoV-2 were also detected in these samples. However, cross-reactivity against other coronaviruses was not detected by the microarray assay. Postvaccination samples showed significantly higher levels of total antibodies, IgG, and IgA targeting SARS-CoV-2 S protein compared with prevaccination samples (eg, mean total antibodies: 8955.0 AU/mL; 95% CI, -5025.0 to 22936.0 arbitrary units/mL; P = .002). In addition, significantly higher anti-SARS S1 IgG levels were detected following vaccination (mean reactivity index, 55.4; 95% CI, -9.1 to 120.0; P = .001), suggesting potential cross-reactivity with these coronaviruses. Also, anti-S NAbs were significantly boosted against SARS-CoV-2 (50.5% neutralization; 95% CI, 17.6% to 83.2% neutralization; P < .001) after vaccination. Furthermore, there was no significant increase in antibody-dependent cellular cytotoxicity against SARS-CoV-2 S protein postvaccination. Conclusions and Relevance: This cohort study found a significant boost in cross-reactive NAbs in some patients exposed to MERS-CoV and SARS-CoV-2 antigens. These findings suggest that isolation of broadly reactive antibodies from these patients may help guide the development of a pancoronavirus vaccine by targeting cross-reactive epitopes between distinct strains of human coronaviruses.

EVALUATION OF HYDROCORTISONE, VITAMIN C, AND THIAMINE FOR THE TREATMENT OF SEPTIC SHOCK: A RANDOMIZED CONTROLLED TRIAL (THE HYVITS TRIAL).

ABSTRACT: Purpose: The aim of the study is to evaluate the effect of combined hydrocortisone, vitamin C, and thiamine (triple therapy) on the mortality of patients with septic shock. Methods : This multicenter, open-label, two-arm parallel-group, randomized controlled trial was conducted in four intensive care units in Qatar. Adult patients diagnosed with septic shock requiring norepinephrine at a rate of ≥0.1 µg/kg/min for ≥6 h were randomized to a triple therapy group or a control group. The primary outcome was in-hospital mortality at 60 days or at discharge, whichever occurred first. Secondary outcomes included time to death, change in Sequential Organ Failure Assessment (SOFA) score at 72 h of randomization, intensive care unit length of stay, hospital length of stay, and vasopressor duration. Results: A total of 106 patients (53 in each group) were enrolled in this study. The study was terminated early because of a lack of funding. The median baseline SOFA score was 10 (interquartile range, 8-12). The primary outcomes were similar between the two groups (triple therapy, 28.3% vs. control, 35.8%; P = 0.41). Vasopressor duration among the survivors was similar between the two groups (triple therapy, 50 h vs. control, 58 h; P = 0.44). Other secondary and safety endpoints were similar between the two groups. Conclusion: Triple therapy did not improve in-hospital mortality at 60 days in critically ill patients with septic shock or reduce the vasopressor duration or SOFA score at 72 h. Trial Registration:ClinicalTrials.gov identifier: NCT03380507. Registered on December 21, 2017.

Persistence of spike-specific immune responses in BNT162b2-vaccinated donors and generation of rapid ex-vivo T cells expansion protocol for adoptive immunotherapy: A pilot study.

Introduction: The BNT162b2 mRNA-based vaccine has shown high efficacy in preventing COVID-19 infection but there are limited data on the types and persistence of the humoral and T cell responses to such a vaccine. Methods: Here, we dissect the vaccine-induced humoral and cellular responses in a cohort of six healthy recipients of two doses of this vaccine. Results and discussion: Overall, there was heterogeneity in the spike-specific humoral and cellular responses among vaccinated individuals. Interestingly, we demonstrated that anti-spike antibody levels detected by a novel simple automated assay (Jess) were strongly correlated (r=0.863, P<0.0001) with neutralizing activity; thus, providing a potential surrogate for neutralizing cell-based assays. The spike-specific T cell response was measured with a newly modified T-spot assay in which the high-homology peptide-sequences cross-reactive with other coronaviruses were removed. This response was induced in 4/6 participants after the first dose, and all six participants after the second dose, and remained detectable in 4/6 participants five months post-vaccination. We have also shown for the first time, that BNT162b2 vaccine enhanced T cell responses also against known human common viruses. In addition, we demonstrated the efficacy of a rapid ex-vivo T cell expansion protocol for spike-specific T cell expansion to be potentially used for adoptive-cell therapy in severe COVID-19, immunocompromised individuals, and other high-risk groups. There was a 9 to 13.7-fold increase in the number of expanded T cells with a significant increase of anti-spike specific response showing higher frequencies of both activation and cytotoxic markers. Interestingly, effector memory T cells were dominant in all four participants' CD8+ expanded memory T cells; CD4+ T cells were dominated by effector memory in 2/4 participants and by central memory in the remaining two participants. Moreover, we found that high frequencies of CD4+ terminally differentiated memory T cells were associated with a greater reduction of spike-specific activated CD4+ T cells. Finally, we showed that participants who had a CD4+ central memory T cell dominance expressed a high CD69 activation marker in the CD4+ activated T cells.

Bleeding Hazard of Percutaneous Tracheostomy in COVID-19 Patients Supported With Venovenous Extracorporeal Membrane Oxygenation: A Case Series.

OBJECTIVES: Tracheostomy usually is performed to aid weaning from mechanical ventilation and facilitate rehabilitation and secretion clearance. Little is known about the safety of percutaneous tracheostomy in patients with severe COVID-19 supported on venovenous extracorporeal membrane oxygenation (VV-ECMO). This study aimed to investigate the bleeding risk of bedside percutaneous tracheostomy in patients with COVID-19 infection supported with VV-ECMO. DESIGN: A Retrospective review of electronic data for routine care of patients on ECMO. SETTING: Tertiary, university-affiliated national ECMO center. PARTICIPANTS: Patients with COVID-19 who underwent percutaneous tracheostomy while on VV-ECMO support. INTERVENTIONS: No intervention was conducted during this study. MEASUREMENTS AND MAIN RESULTS: Electronic medical records of 16 confirmed patients with COVID-19 who underwent percutaneous tracheostomy while on VV-ECMO support, including patient demographics, severity of illness, clinical variables, procedural complications, and outcomes, were compared with 16 non-COVID-19 patients. The SPSS statistical software was used for statistical analysis. The demographic data were compared using the chi-square test, and normality assumption was tested using the Shapiro-Wilk test. The indications for tracheostomy in all the patients were prolonged mechanical ventilation and sedation management. None of the patients suffered a life-threatening procedural complication within 48 hours. Moderate-to-severe bleeding was similar in both groups. There was no difference in 30- and 90-days mortality between both groups. As per routine screening results, none of the staff involved contracted COVID-19 infection. CONCLUSIONS: In this case series, percutaneous tracheostomy during VV-ECMO in patients with COVID-19 appeared to be safe and did not pose additional risks to patients or healthcare workers.

Transfusion practice in patients receiving VV ECMO (PROTECMO): a prospective, multicentre, observational study.

BACKGROUND: In patients receiving venovenous (VV) extracorporeal membrane oxygenation (ECMO) packed red blood cell (PRBC) transfusion thresholds are usually higher than in other patients who are critically ill. Available guidelines suggest a restrictive approach, but do not provide specific recommendations on the topic. The main aim of this study was, in a short timeframe, to describe the actual values of haemoglobin and the rate and the thresholds for transfusion of PRBC during VV ECMO. METHODS: PROTECMO was a multicentre, prospective, cohort study done in 41 ECMO centres in Europe, North America, Asia, and Australia. Consecutive adult patients with acute respiratory distress syndrome (ARDS) who were receiving VV ECMO were eligible for inclusion. Patients younger than 18 years, those who were not able to provide informed consent when required, and patients with an ECMO stay of less than 24 h were excluded. Our main aim was to monitor the daily haemoglobin concentration and the value at the point of PRBC transfusion, as well as the rate of transfusions. The practice in different centres was stratified by continent location and case volume per year. Adjusted estimates were calculated using marginal structural models with inverse probability weighting, accounting for baseline and time varying confounding. FINDINGS: Between Dec 1, 2018, and Feb 22, 2021, 604 patients were enrolled (431 [71%] men, 173 [29%] women; mean age 50 years [SD 13·6]; and mean haemoglobin concentration at cannulation 10·9 g/dL [2·4]). Over 7944 ECMO days, mean haemoglobin concentration was 9·1 g/dL (1·2), with lower concentrations in North America and high-volume centres. PRBC were transfused on 2432 (31%) of days on ECMO, and 504 (83%) patients received at least one PRBC unit. Overall, mean pretransfusion haemoglobin concentration was 8·1 g/dL (1·1), but varied according to the clinical rationale for transfusion. In a time-dependent Cox model, haemoglobin concentration of less than 7 g/dL was consistently associated with higher risk of death in the intensive care unit compared with other higher haemoglobin concentrations (hazard ratio [HR] 2·99 [95% CI 1·95-4·60]); PRBC transfusion was associated with lower risk of death only when transfused when haemoglobin concentration was less than 7 g/dL (HR 0·15 [0·03-0·74]), although no significant effect in reducing mortality was reported for transfusions for other haemoglobin classes (7·0-7·9 g/dL, 8·0-9·9 g/dL, or higher than 10 g/dL). INTERPRETATION: During VV ECMO, there was no universally accepted threshold for transfusion, but PRBC transfusion was invariably associated with lower mortality only when done with haemoglobin concentration of less than 7 g/dL. FUNDING: Extracorporeal Life Support Organization.

Cost-Effectiveness Analysis of Out-Of-Hospital versus In-Hospital Extracorporeal Cardiopulmonary Resuscitation for Out-Hospital Refractory Cardiac Arrest.

It has been speculated that out-of-hospital cardiac arrest (OHCA) patients' survival might be improved by implementing extracorporeal cardiopulmonary resuscitation (ECPR) before arrival to hospital. Therefore, we sought to assess the cost-effectiveness of OH-ECPR versus in-hospital (IH)-ECPR in OHCA patients in Qatar. From the hospital perspective, a conventional decision-analytic model was constructed to follow up the clinical and economic consequences of OH-ECPR versus IH-ECPR in a simulated OHCA population over one year. The primary outcome was the survival at discharge after arrest as well as the overall direct healthcare costs of managing OHCA patients. The robustness of this model was evaluated via sensitivity analyses. The OH-ECPR yielded 16% survival at discharge after arrest compared to 7% with IH-ECPR, [risk ratio (RR)=0.91; 95% CI 0.79 to 1.06; P = 0.26]. Incorporating the uncertainty associated with this survival rate, and based on the estimated willingness to pay threshold in Qatar, the OH-ECPR was cost-effective with an incremental cost-effectiveness ratio of QAR 464,589 (USD 127,634). Sensitivity and uncertainty analyses confirmed the robustness of the study outcome. This is the first cost-effectiveness evaluation of OH-ECPR versus IH-ECPR in OHCA patients. OH-ECPR is potentially an economically acceptable resuscitative strategy in Qatar.

Variability in Skeletal Muscle Protein Synthesis Rates in Critically Ill Patients.

(1) Background: Muscle protein synthesis in critically ill patients is, on average, normal despite dramatic muscle loss, but the variation is much larger than in controls. Here, we evaluate if this variation is due to 1) heterogeneity in synthesis rates, 2) morphological variation or infiltrating cells, or 3) heterogeneity in the synthesis of different protein fractions. (2) Methods: Muscle biopsies were taken from both legs of critically ill patients (n = 17). Mixed and mitochondrial protein synthesis rates and morphologies were evaluated in both legs. Synthesis rates of myosin and actin were determined in combined biopsies and compared with controls. (3) Results: Muscle protein synthesis rates had a large variability in the patients (1.4-10.8%/day). No differences in mixed and mitochondrial protein synthesis rates between both legs were observed. A microscopic examination revealed no morphological differences between the two legs or any infiltrating inflammatory cells. The synthesis rates for myosin were lower and for actin they were higher in the muscles of critically ill patients, compared with the controls. (4) Conclusions: The large variation in muscle protein synthesis rates in critically ill patients is not the result of heterogeneity in synthesis rates, nor due to infiltrating cells. There are differences in the synthesis rates of different proteins, but these do not explain the larger variations.

Association of periodontal therapy, with inflammatory biomarkers and complications in COVID-19 patients: a case control study.

BACKGROUND: In previous studies, COVID-19 complications were reported to be associated with periodontitis. Accordingly, this study was designed to test the hypothesis that a history of periodontal therapy could be associated with lower risk of COVID-19 complications. METHODS: A case-control study was performed using the medical health records of COVID-19 patients in the State of Qatar between March 2020 and February 2021 and dental records between January 2017 and December 2021. Cases were defined as COVID-19 patients who suffered complications (death, ICU admissions and/or mechanical ventilation); controls were COVID-19 patients who recovered without major complications. Associations between a history of periodontal therapy and COVID-19 complications were analysed using logistic regression models adjusted for demographic and medical factors. Blood parameters were compared using Kruskal-Wallis test. RESULTS: In total, 1,325 patients were included. Adjusted odds ratio (AOR) analysis revealed that non-treated periodontitis was associated with significant risk of need for mechanical ventilation (AOR = 3.91, 95% CI 1.21-12.57, p = 0.022) compared to periodontally healthy patients, while treated periodontitis was not (AOR = 1.28, 95% CI 0.25-6.58, p = 0.768). Blood analyses revealed that periodontitis patients with a history of periodontal therapy had significantly lower levels of D-dimer and Ferritin than non-treated periodontitis patients. CONCLUSION: Among COVID-19 patients with periodontal bone loss, only those that have not received periodontal therapy had higher risk of need for assisted ventilation. COVID-19 patients with a history of periodontal therapy were associated with significantly lower D-dimer levels than those without recent records of periodontal therapy. CLINICAL RELEVANCE: The fact that patients with treated periodontitis were less likely to suffer COVID-19 complications than non-treated ones further strengthen the hypothesis linking periodontitis to COVID-19 complications and suggests that managing periodontitis could help reduce the risk for COVID-19 complications, although future research is needed to verify this.

IoT-based mock oxygenator for extracorporeal membrane oxygenation simulator.

BACKGROUND: Training is an essential aspect of providing high-quality treatment and ensuring patient safety in any medical practice. Because extracorporeal membrane oxygenation (ECMO) is a complicated operation with various elements, variables, and irregular situations, doctors must be experienced and knowledgeable about all conventional protocols and emergency procedures. The conventional simulation approach has a number of limitations. The approach is intrinsically costly since it relies on disposable medical equipment (i.e., oxygenators, heat exchangers, and pumps) that must be replaced regularly due to the damage caused by the liquid used to simulate blood. The oxygenator, which oxygenates the blood through a tailored membrane in ECMO, acts as a replacement for the patient's natural lung. For the context of simulation-based training (SBT) oxygenators are often expensive and cannot be recycled owing to contamination issues. METHODS: Consequently, it is advised that the training process include a simulated version of oxygenators to optimize reusability and decrease training expenses. Toward this goal, this article demonstrates a mock oxygenator for ECMO SBT, designed to precisely replicate the real machine structure and operation. RESULTS: The initial model was reproduced using 3D modeling and printing. Additionally, the mock oxygenator could mimic frequent events such as pump noise and clotting. Furthermore, the oxygenator is integrated with the modular ECMO simulator using cloud-based communication technology that goes in hand with the internet of things technology to provide remote control via an instructor tablet application. CONCLUSIONS: The final 3D modeled oxygenator body was tested and integrated with the other simulation modules at Hamad Medical Corporation with several participants to evaluate the effectiveness of the training session.

Prognostic tools and candidate drugs based on plasma proteomics of patients with severe COVID-19 complications.

COVID-19 complications still present a huge burden on healthcare systems and warrant predictive risk models to triage patients and inform early intervention. Here, we profile 893 plasma proteins from 50 severe and 50 mild-moderate COVID-19 patients, and 50 healthy controls, and show that 375 proteins are differentially expressed in the plasma of severe COVID-19 patients. These differentially expressed plasma proteins are implicated in the pathogenesis of COVID-19 and present targets for candidate drugs to prevent or treat severe complications. Based on the plasma proteomics and clinical lab tests, we also report a 12-plasma protein signature and a model of seven routine clinical tests that validate in an independent cohort as early risk predictors of COVID-19 severity and patient survival. The risk predictors and candidate drugs described in our study can be used and developed for personalized management of SARS-CoV-2 infected patients.

Emerging COVID-19 variants and their impact on SARS-CoV-2 diagnosis, therapeutics and vaccines.

The emergence of novel and evolving variants of SARS-CoV-2 has fostered the need for change in the form of newer and more adaptive diagnostic methods for the detection of SARS-CoV-2 infections. On the other hand, developing rapid and sensitive diagnostic technologies is now more challenging due to emerging variants and varying symptoms exhibited among the infected individuals. In addition to this, vaccines remain the major mainstay of prevention and protection against infection. Novel vaccines and drugs are constantly being developed to unleash an immune response for the robust targeting of SARS-CoV-2 and its associated variants. In this review, we provide an updated perspective on the current challenges posed by the emergence of novel SARS-CoV-2 mutants/variants and the evolution of diagnostic techniques to enable their detection. In addition, we also discuss the development, formulation, working mechanisms, advantages, and drawbacks of some of the most used vaccines/therapeutic drugs and their subsequent immunological impact.Key messageThe emergence of novel variants of the SARS-CoV-2 in the past couple of months, highlights one of the primary challenges in the diagnostics, treatment, as well as vaccine development against the virus.Advancements in SARS-CoV-2 detection include nucleic acid based, antigen and immuno- assay-based and antibody-based detection methodologies for efficient, robust, and quick testing; while advancements in COVID-19 preventive and therapeutic strategies include novel antiviral and immunomodulatory drugs and SARS-CoV-2 targeted vaccines.The varied COVID-19 vaccine platforms and the immune responses induced by each one of them as well as their ability to battle post-vaccination infections have all been discussed in this review.

A Review of Human Circulatory System Simulation: Bridging the Gap between Engineering and Medicine.

(1) Background: Simulation-based training (SBT) is the practice of using hands-on training to immerse learners in a risk-free and high-fidelity environment. SBT is used in various fields due to its risk-free benefits from a safety and an economic perspective. In addition, SBT provides immersive training unmatched by traditional teaching the interactive visualization needed in particular scenarios. Medical SBT is a prevalent practice as it allows for a platform for learners to learn in a risk-free and cost-effective environment, especially in critical care, as mistakes could easily cause fatalities. An essential category of care is human circulatory system care (HCSC), which includes essential-to-simulate complications such as cardiac arrest. (2) Methods: In this paper, a deeper look onto existing human circulatory system medical SBT is presented to assess and highlight the important features that should be present with a focus on extracorporeal membrane oxygenation cannulation (ECMO) simulators and cardiac catheterization. (3) Results: A list of features is also suggested for an ideal simulator to bridge the gap between medical studies and simulator engineering, followed by a case study of an ECMO SBT system design. (4) Conclusions: a collection and discussion of existing work for HCSC SBT are portrayed as a guide for researchers and practitioners to compare existing SBT and recreating them effectively.

Mortality Prediction Utilizing Blood Biomarkers to Predict the Severity of COVID-19 Using Machine Learning Technique.

Healthcare researchers have been working on mortality prediction for COVID-19 patients with differing levels of severity. A rapid and reliable clinical evaluation of disease intensity will assist in the allocation and prioritization of mortality mitigation resources. The novelty of the work proposed in this paper is an early prediction model of high mortality risk for both COVID-19 and non-COVID-19 patients, which provides state-of-the-art performance, in an external validation cohort from a different population. Retrospective research was performed on two separate hospital datasets from two different countries for model development and validation. In the first dataset, COVID-19 and non-COVID-19 patients were admitted to the emergency department in Boston (24 March 2020 to 30 April 2020), and in the second dataset, 375 COVID-19 patients were admitted to Tongji Hospital in China (10 January 2020 to 18 February 2020). The key parameters to predict the risk of mortality for COVID-19 and non-COVID-19 patients were identified and a nomogram-based scoring technique was developed using the top-ranked five parameters. Age, Lymphocyte count, D-dimer, CRP, and Creatinine (ALDCC), information acquired at hospital admission, were identified by the logistic regression model as the primary predictors of hospital death. For the development cohort, and internal and external validation cohorts, the area under the curves (AUCs) were 0.987, 0.999, and 0.992, respectively. All the patients are categorized into three groups using ALDCC score and death probability: Low (probability < 5%), Moderate (5% < probability < 50%), and High (probability > 50%) risk groups. The prognostic model, nomogram, and ALDCC score will be able to assist in the early identification of both COVID-19 and non-COVID-19 patients with high mortality risk, helping physicians to improve patient management.

Advanced Thermochromic Ink System for Medical Blood Simulation.

Simulators for extracorporeal membrane oxygenation (ECMO) have problems of bulky devices and low-fidelity methodologies. Hence, ongoing efforts for optimizing modern solutions focus on minimizing expenses and blending training with the intensive care unit. This is particularly evident following the coronavirus pandemic, where economic resources have been extensively cut. In this paper, as a part of an ECMO simulator for training management, an advance thermochromic ink system for medical blood simulation is presented. The system was developed and enhanced as a prototype with successful and reversible transitions between dark and bright red blood color to simulate blood oxygenation and deoxygenation in ECMO training sessions.

A Modular Approach for a Patient Unit for Extracorporeal Membrane Oxygenation Simulator.

Despite many advancements in extracorporeal membrane oxygenation (ECMO), the procedure is still correlated with a high risk of patient complications. Simulation-based training provides the opportunity for ECMO staff to practice on real-life scenarios without exposing ECMO patients to medical errors while practicing. At Hamad Medical Corporation (HMC) in Qatar, there is a critical need of expert ECMO staff. Thus, a modular ECMO simulator is being developed to enhance the training process in a cost-effective manner. This ECMO simulator gives the instructor the ability to control the simulation modules and run common simulation scenarios through a tablet application. The core modules of the simulation system are placed in the patient unit. The unit is designed modularly such that more modules can be added throughout the simulation sessions to increase the realism of the simulation sessions. The new approach is to enclose the patient unit in a trolley, which is custom-designed and made to include all the components in a modular fashion. Each module is enclosed in a separate box and then mounted to the main blood simulation loop box using screws, quick connect/disconnect liquid fittings, and electrical plugs. This method allows fast upgrade and maintenance for each module separately as well as upgrading modules easily without modifying the trolley's design. The prototype patient unit has been developed for portability, maintenance, and extensibility. After implementation and testing, the prototype has proven to successfully simulate the main visual and audio cues of the real emergency scenarios, while keeping costs to a minimum.

Association between periodontitis and severity of COVID-19 infection: A case-control study.

AIM: COVID-19 is associated with an exacerbated inflammatory response that can result in fatal outcomes. Systemic inflammation is also a main characteristic of periodontitis. Therefore, we investigated the association of periodontitis with COVID-19 complications. MATERIALS AND METHODS: A case-control study was performed using the national electronic health records of the State of Qatar between February and July 2020. Cases were defined as patients who suffered COVID-19 complications (death, ICU admissions or assisted ventilation), and controls were COVID-19 patients discharged without major complications. Periodontal conditions were assessed using dental radiographs from the same database. Associations between periodontitis and COVID 19 complications were analysed using logistic regression models adjusted for demographic, medical and behaviour factors. RESULTS: In total, 568 patients were included. After adjusting for potential confounders, periodontitis was associated with COVID-19 complication including death (OR = 8.81, 95% CI 1.00-77.7), ICU admission (OR = 3.54, 95% CI 1.39-9.05) and need for assisted ventilation (OR = 4.57, 95% CI 1.19-17.4). Similarly, blood levels of white blood cells, D-dimer and C Reactive Protein were significantly higher in COVID-19 patients with periodontitis. CONCLUSION: Periodontitis was associated with higher risk of ICU admission, need for assisted ventilation and death of COVID-19 patients, and with increased blood levels of biomarkers linked to worse disease outcomes.