New understanding of the damage of SARS-CoV-2 infection outside the respiratory system

SARS-CoV-2: A synergy to the Alzheimer's disease

COVID-19 was a nightmare in humankind's history that challenged our advanced medical technology. All credit goes to the researchers who played a crucial role in curbing COVID-19 and proved our medical technology supremacy. However, COVID-19 has left some mysterious scars on human well-being. It is believed that COVID-19 has a significant negative impact on various cardiovascular (CVS) and central nervous system (CNS) diseases, especially in the case of CNS diseases like Alzheimer's. Surprisingly, COVID-19 affects the respiratory system, whereas Alzheimer's disease (AD) alters brain function. To explain this phenomenon, several hypotheses were proposed, but the mechanism needs to be clearly understood. Another critical thing to be concerned about is that COVID-19 will worsen pre-existing conditions and lead to the onset of AD. In the race to curb COVID-19, the invention of vaccines was speeded up, and it is necessary to fight against COVID-19. However, postvaccination follow-up is mandatory when an individual is a victim of AD. In this review article, we compiled the various dreadful effects of the COVID-19 virus on AD, the Post effects of the virus on AD, and the effect of the COVID-19 vaccination on AD. This article provides a new direction for research concerning COVID-19 and AD.

Anxiety and depression in people with epilepsy during and one year after the COVID-19 pandemic

OBJECTIVE

Compare the prevalence and severity of anxiety and depression among people with epilepsy (PWE) evaluated by telemedicine during the initial stages of the COVID-19 pandemic and follow up on their status 15 months later.

METHODS

We conducted a prospective, observational, and analytical study at the Epilepsy Clinic of the National Institute of Neurology and Neurosurgery (NINN) in Mexico City during the COVID-19 pandemic. HADS-A and HADS-D instruments were administered to adult patients diagnosed with epilepsy, initially through telemedicine and later through in-person visits or phone calls after one year.

RESULTS

A sample of 115 patients was obtained, with 62.5% being women. The mean age of the patients was 33.6 years (± 12), and the mean age of epilepsy onset was 16.82 years (± 13.82). The majority of patients had focal epilepsy (78.3%), and only 42% reported being seizure-free. The results from the HADS-A scale showed that 48.69% of the patients had anxiety. On the HADS-D scale, 29.56% of the patients were found to have depression. At follow-up, the HADS-A results indicated that 50.64% of the patients had anxiety, and the HADS-D results showed that 36.36% had depression. An analysis of associations between sociodemographic or clinical variables and the presence of anxiety and/or depression in PWE revealed no statistically significant results, except for the clinical variable of patients taking anxiolytic or antidepressant medications during the assessment. These patients had lower HADS-A and HADS-D scores, with a statistically significant p-value of 0.0001.

SIGNIFICANCE

Comparing these findings with a previously published paper by our group showed a significant increase in both depression and anxiety, which were already prevalent in the earlier study. In conclusion, PWE exhibited high levels of anxiety and depression during and one year after the pandemic, despite receiving appropriate treatment. These symptoms, present before the pandemic, have been further exacerbated and continue to persist.

PLAIN LANGUAGE SUMMARY

This study examined anxiety and depression in patients with epilepsy (PWE) during the COVID-19 pandemic at the National Institute of Neurology and Neurosurgery in Mexico. Using the HADS-A and HADS-D scales, 115 patients were assessed over a year. Results showed that 48.69% had anxiety and 29.56% had depression, with both increasing to 50.64% and 36.36%, respectively, after one year. The only significant finding was that patients on anxiolytic or antidepressant medication had lower scores for anxiety and depression. The study concludes that anxiety and depression in PWE worsened during the pandemic and persisted despite treatment.

Combination of spatial transcriptomics analysis and retrospective study reveals liver infection of SARS-COV-2 is associated with clinical outcomes of COVID-19

BACKGROUND

Liver involvement is a common complication of coronavirus disease 2019 (COVID-19), especially in hospitalized patients. However, the underlying mechanisms involved are not fully understood.

METHODS

Immunohistochemistry (IHC) staining of SARS-CoV-2 spike (S) and nucleocapsid (N) proteins was conducted on liver tissues from six patients with COVID-19. The 10x Genomics Visium CytAssist Spatial Gene Assay was designed to analyze liver transcriptomics. TCR CDR3 sequences were analyzed in DNA from liver tissues. Liver function indicators were retrospectively studied in 650 hospitalized patients with COVID-19.

FINDINGS

SARS-CoV-2 proteins were initially detected in the livers of naturally infected golden (Syrian) hamsters, prompting us to investigate the situation in clinical cases. Thus, we collected liver tissues from patients with abnormal liver biochemical values. Viral S and N proteins were detected in the livers of severe and deceased patients but not in those of moderate patients. We further demonstrated that hepatocytes and erythroid cells in hepatic sinusoids are major cells targeted by SARS-CoV-2. Immune cells, especially T cells, were enriched in surviving severe patients, characterized by enhanced CDR3α clonality and novel CDR3β recombination of the T-cell receptor. In contrast, hepatocyte apoptosis was triggered, and the transcription of albumin (ALB) was obviously impaired in the deceased patients. We then performed a retrospective study including patients with COVID-19. Serum aspartate aminotransferase (AST) and ALB levels at baseline significantly differed in the deceased cohort. However, AST regression did not decrease the risk of death. ALB recovery indicated clinical improvement, and declining or low serum ALB concentrations were associated with death.

INTERPRETATION

This study provides clinical evidence for liver infection with SARS-CoV-2, insight into the impact of SARS-CoV-2 on the liver, and a potential way to evaluate the risk of death via assessing serum ALB concentration fluctuations in patients with COVID-19.

FUNDING

National Key R&D Program of China (2021YFC2300602), National Natural Science Foundation of China (92369110), National Natural Science Foundation of China (U23A20474), Shanghai Municipal Science and Technology Major Project (ZD2021CY001), Shanghai Jinshan District Medical and Health Technology Innovation Fund Project (2023-WS-31).

COVID-19 in patients with multiple sclerosis-A narrative review

BACKGROUND

Multiple sclerosis (MS) is a complex neurodegenerative disease characterized by immune dysregulation, affecting over 2.5 million people worldwide. Interestingly, COVID-19 infection can cause neurodegeneration through demyelination similar to that of MS, and COVID-19 infection can lead to long-term neurological sequelae, post-COVID-19 neurological syndrome. These overlapping neurological mechanisms suggest that patients with MS (PwMS) may have a unique and potentially more complex relationship with COVID-19.

DISCUSSION AND CONCLUSION

The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) can enter the central nervous system via the olfactory nerve or through interactions with angiotensin-converting enzyme-2 receptors in the blood-brain barrier, potentially initiating or enhancing neurodegenerative processes through demyelination. The risk of SARS-CoV-2 infection among PwMS is similar to that of the general population; however, PwMS with higher Expanded Disability Status Scale scores, longer MS duration, or progressive forms of MS are at an increased risk for developing severe COVID-19 outcomes. Most disease-modifying therapies (DMT), such as interferon, glatiramer, teriflunomide, and cladribine, do not appear to affect the risk of COVID-19 infection, the severity of COVID-19 illness, or the response to COVID-19 vaccines. As a result, these therapies should be continued during COVID-19 infection in PwMS. Rituximab, however, has been shown to increase the risk of severe COVID-19 outcomes. For managing symptomatic COVID-19 infection in PwMS, remdesivir and neutralizing monoclonal antibodies are shown to be effective. COVID-19-associated cytokine release syndrome can be managed with corticosteroids. Importantly, COVID-19 infection does not increase susceptibility to MS relapses or exacerbate the progression of MS symptoms. Furthermore, COVID-19 vaccination is encouraged for all MS patients, particularly those at greater risk of severe outcomes, as it does not trigger relapses, exacerbate MS symptoms, or diminish the efficacy of DMT. Despite these findings, high-quality evidence remains lacking to fully establish the relationship between COVID-19 and MS, highlighting the need for further research in this area.

Neurological complications caused by SARS-CoV-2

SUMMARYSARS-CoV-2 can not only cause respiratory symptoms but also lead to neurological complications. Research has shown that more than 30% of SARS-CoV-2 patients present neurologic symptoms during COVID-19 (A. Pezzini and A. Padovani, Nat Rev Neurol 16:636-644, 2020, https://doi.org/10.1038/s41582-020-0398-3). Increasing evidence suggests that SARS-CoV-2 can invade both the central nervous system (CNS) (M.S. Xydakis, M.W. Albers, E.H. Holbrook, et al. Lancet Neurol 20: 753-761, 2021 https://doi.org/10.1016/S1474-4422(21)00182-4 ) and the peripheral nervous system (PNS) (M.N. Soares, M. Eggelbusch, E. Naddaf, et al. J Cachexia Sarcopenia Muscle 13:11-22, 2022, https://doi.org/10.1002/jcsm.12896), resulting in a variety of neurological disorders. This review summarized the CNS complications caused by SARS-CoV-2 infection, including encephalopathy, neurodegenerative diseases, and delirium. Additionally, some PNS disorders such as skeletal muscle damage and inflammation, anosmia, smell or taste impairment, myasthenia gravis, Guillain-Barré syndrome, ICU-acquired weakness, and post-acute sequelae of COVID-19 were described. Furthermore, the mechanisms underlying SARS-CoV-2-induced neurological disorders were also discussed, including entering the brain through retrograde neuronal or hematogenous routes, disrupting the normal function of the CNS through cytokine storms, inducing cerebral ischemia or hypoxia, thus leading to neurological complications. Moreover, an overview of long-COVID-19 symptoms is provided, along with some recommendations for care and therapeutic approaches of COVID-19 patients experiencing neurological complications.

The impact of COVID-19 on the male reproductive system

OBJECTIVE

The relevance of the study is determined by the deepening understanding of the global consequences of the coronavirus pandemic, which affect not only lung health but also a wide range of other body systems. In light of new data on the long-term effects of coronavirus infection, this study is highly significant. The purpose of this study is to investigate the impact of coronavirus infection on the male reproductive system and assess its potential influence on male fertility to refine the mechanisms of damage and provide recommendations for medical care.

METHODS

The study utilised a combination of methods, including a meta-analysis of medical organisation databases, analysis of clinical cases, representative sample method, and quantitative survey method. These approaches allowed for a comprehensive and multifaceted view of the problem.

RESULTS

The samples of sperm showed a noticeable decrease in progressive motility, sperm concentration, and volume, especially in patients with moderate and severe symptoms of COVID-19, whereas patients with mild symptoms only experienced a decrease in progressive motility and overall sperm motility. The survey identified symptoms of male reproductive system dysfunction after recovering from COVID-19. Predominant symptoms included decreased libido (15%), impotence (13%), and infections of the genital organs (12%). Most surveyed men lacked sufficient awareness of other aspects of male reproductive health, including infections, genetic defects, chronic diseases, and available medical services.

CONCLUSIONS

As a result of the study, it was concluded that coronavirus infection can have a negative impact on the male reproductive system. The practical value of this study lies in improving approaches to medical care for men who have recovered from COVID-19 and creating preventive programmes.

The Effect of COVID-19 and COVID-19 Vaccination on Assisted Human Reproduction Outcomes: A Systematic Review and Meta-Analysis

The most discussed infectious disease is coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus. Many research endeavors have focused on the effects of the virus on reproductive organs, as these have also been shown to carry the receptors to which the virus attaches. The results of assisted reproductive technology (ART) have been significantly affected by the pandemic, with some in vitro fertilization (IVF) centers being closed due to the risk of further spread of the disease. According to World Health Organization statistics, 17.5% of adults worldwide suffered from fertility problems in 2023; in other words, one in six people in the world have reproductive health problems. As infertility is a growing problem in the modern world and new developments in assisted reproduction are always a topic of profound interest, it is important to understand the impact of SARS-CoV-2 on reproductive health. This systematic review aimed to examine studies describing patients undergoing ART procedures with a COVID-19-positive history and to shed light on the recent evidence on the safety of COVID-19 vaccination in the ART context. A meta-analysis was conducted to confirm the results of the systematic review. The results showed a significant difference in clinical pregnancy rates between the vaccinated and unvaccinated groups and an increased miscarriage rate in those with a COVID-19-positive history. However, no significant difference in clinical pregnancy and birth rates was found in participants with a previous COVID-19 infection. The results show that further studies and research are needed, even though the spread and impact of the virus have decreased. Evidence-based information for individuals and couples undergoing infertility treatment is vital to enable informed decision-making.

SARS-CoV-2-induced disruption of a vascular bed in a microphysiological system caused by type-I interferon from bronchial organoids

Blood vessels show various COVID-19-related conditions including thrombosis and cytokine propagation. Existing in vitro blood vessel models cannot represent the consequent changes in the vascular structure or determine the initial infection site, making it difficult to evaluate how epithelial and endothelial tissues are damaged. Here, we developed a microphysiological system (MPS) that co-culture the bronchial organoids and the vascular bed to analyze infection site and interactions. In this system, virus-infected organoids caused damage in vascular structure. However, vasculature was not damaged or infected when the virus was directly introduced to vascular bed. The knockout of interferon-related genes and inhibition of the JAK/STAT pathway reduced the vascular damage, indicating the protective effect of interferon response suppression. The results demonstrate selective infection of bronchial epithelial cells and vascular damage by cytokines and also indicate the applicability of MPS to investigate how the infection influences vascular structure and functions.

Identifying plant-derived antiviral alkaloids as dual inhibitors of SARS-CoV-2 main protease and spike glycoprotein through computational screening

COVID-19 is currently considered the ninth-deadliest pandemic, spreading through direct or indirect contact with infected individuals. It has imposed a consistent strain on both the financial and healthcare resources of many countries. To address this challenge, there is a pressing need for the development of new potential therapeutic agents for the treatment of this disease. To identify potential antiviral agents as novel dual inhibitors of SARS-CoV-2, we retrieved 404 alkaloids from 12 selected medicinal antiviral plants and virtually screened them against the renowned catalytic sites and favorable interacting residues of two essential proteins of SARS-CoV-2, namely, the main protease and spike glycoprotein. Based on docking scores, 12 metabolites with dual inhibitory potential were subjected to drug-likeness, bioactivity scores, and drug-like ability analyses. These analyses included the ligand-receptor stability and interactions at the potential active sites of target proteins, which were analyzed and confirmed through molecular dynamic simulations of the three lead metabolites. We also conducted a detailed binding free energy analysis of pivotal SARS-CoV-2 protein inhibitors using molecular mechanics techniques to reveal their interaction dynamics and stability. Overall, our results demonstrated that 12 alkaloids, namely, adouetine Y, evodiamide C, ergosine, hayatinine, (+)-homoaromoline, isatithioetherin C, N,alpha-L-rhamnopyranosyl vincosamide, pelosine, reserpine, toddalidimerine, toddayanis, and zanthocadinanine, are shortlisted as metabolites based on their interactions with target proteins. All 12 lead metabolites exhibited a higher unbound fraction and therefore greater distribution compared with the standards. Particularly, adouetine Y demonstrated high docking scores but exhibited a nonspontaneous binding profile. In contrast, ergosine and evodiamide C showed favorable binding interactions and superior stability in molecular dynamics simulations. Ergosine demonstrated exceptional performance in several key pharmaceutical metrics. Pharmacokinetic evaluations revealed that ergosine exhibited pronounced bioactivity, good absorption, and optimal bioavailability. Additionally, it was predicted not to cause skin sensitivity and was found to be non-hepatotoxic. Importantly, ergosine and evodiamide C emerged as superior drug candidates for dual inhibition of SARS-CoV-2 due to their strong binding affinity and drug-like ability, comparable to known inhibitors like N3 and molnupiravir. This study is limited by its in silico nature and demands the need for future in vitro and in vivo studies to confirm these findings.

EEG signatures of cognitive decline after mild SARS-CoV-2 infection: an age-dependent study

BACKGROUND

Current research on the neurological impact of SARS-CoV-2 primarily focuses on the elderly or severely ill individuals. This study aims to explore the diverse neurological consequences of SARS-CoV-2 infection, with a particular focus on mildly affected children and adolescents.

METHODS

A cohort study was conducted to collect pre- and post-infection resting-state electroencephalogram (EEG) data from 185 participants and 181 structured questionnaires of long-term symptoms across four distinct age groups. The goal was to comprehensively evaluate the impact of SARS-CoV-2 infection on these different age demographics. The study analyzed EEG changes of SARS-CoV-2 by potential biomarkers across age groups using both spatial and temporal approaches.

RESULTS

Spatial analysis indicated that children and adolescents exhibit smaller changes in brain network and microstate patterns post-infection, implying a milder cognitive impact. Sequential linear analyses showed that SARS-CoV-2 infection is associated with a marked rise in low-complexity, synchronized neural activity within low-frequency EEG bands. This is evidenced by a significant increase in Hjorth activity within the theta band and Hjorth mobility in the delta band. Sequential nonlinear analysis indicated a significant reduction in the Hurst exponent across all age groups, pointing to increased chaos and complexity within the cognitive system following infection. Furthermore, linear regression analysis based on questionnaires established a significant positive relationship between the magnitude of changes in these neural indicators and the persistence of long-term symptoms post-infection.

CONCLUSIONS

The findings underscore the enduring neurological impacts of SARS-CoV-2 infection, marked by cognitive decline and increased EEG disarray. Although children and adolescents experienced milder effects, cognitive decline and heightened low-frequency electrical activity were evident. These observations might contribute to understanding potential anxiety, insomnia, and neurodevelopmental implications.

Comprehensive Insights Into the Multi-faceted Manifestations of COVID-19: A Narrative Review

The emergence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and the ensuing COVID-19 pandemic had far-reaching and multifaceted effects on global health. This paper provides a comprehensive overview of the physical, extrapulmonary, and psychological manifestations associated with COVID-19. It highlights the wide-ranging impact of the virus on various organ systems, including the respiratory, cardiovascular, renal, gastrointestinal, ocular, dermatologic, and nervous systems. Additionally, it explores the complex connections between COVID-19 infection and neuropsychiatric symptoms, shedding light on the potential underlying mechanisms. The paper also delves into the phenomenon of "long COVID," a condition characterized by persistent symptoms extending well beyond the disease's acute phase. It discusses the diverse and often debilitating symptoms that individuals with long COVID may experience, encompassing physical, cognitive, and psychological aspects. The complexity and variability of long COVID underscore the challenges it poses to healthcare professionals and the importance of ongoing research to understand its underlying mechanisms. Furthermore, the paper touches on the current state of knowledge regarding the aetiology of long COVID and the various approaches to symptom management and treatment. While a definitive cure remains elusive, efforts are underway to alleviate the burden of long COVID through pharmacological interventions, physical therapy, cognitive-behavioral therapy, and support networks. This paper comprehensively explores COVID-19's far-reaching effects, emphasizing the need for a holistic and interdisciplinary approach to understanding and managing the diverse manifestations of this global health challenge. Ongoing research and collaborative efforts are essential in addressing the complex and evolving nature of COVID-19 and its aftermath.

Reduced HDL-cholesterol in long COVID-19: A key metabolic risk factor tied to disease severity

This controlled study investigated metabolic changes in non-vaccinated individuals with Long-COVID-19, along with their connection to the severity of the disease. The study involved 88 patients who experienced varying levels of initial disease severity (mild, moderate, and severe), and a control group of 29 healthy individuals. Metabolic risk markers from fasting blood samples were analyzed, and data regarding disease severity indicators were collected. Findings indicated significant metabolic shifts in severe Long-COVID-19 cases, mainly a marked drop in HDL-C levels and a doubled increase in ferritin levels and insulin resistance compared to the mild cases and controls. HDL-C and ferritin were identified as the leading factors predicted by disease severity. In conclusion, the decline in HDL-C levels and rise in ferritin levels seen in Long-COVID-19 individuals, largely influenced by the severity of the initial infection, could potentially play a role in the persistence and progression of Long-COVID-19. Hence, these markers could be considered as possible therapeutic targets, and help shape preventive strategies to reduce the long-term impacts of the disease.

Synergistic effects of COVID-19 and Pseudomonas aeruginosa in chronic obstructive pulmonary disease: a polymicrobial perspective

This article discusses the connection between the novel coronavirus disease 2019 (COVID-19) caused by the coronavirus-2 (SARS-CoV-2) and chronic obstructive pulmonary disease (COPD). COPD is a multifaceted respiratory illness that is typically observed in individuals with chronic exposure to chemical irritants or severe lung damage caused by various pathogens, including SARS-CoV-2 and Pseudomonas aeruginosa. The pathogenesis of COPD is complex, involving a variety of genotypes and phenotypic characteristics that result in severe co-infections and a poor prognosis if not properly managed. We focus on the role of SARS-CoV-2 infection in severe COPD exacerbations in connection to P.  aeruginosa infection, covering pathogenesis, diagnosis, and therapy. This review also includes a thorough structural overview of COPD and recent developments in understanding its complicated and chronic nature. While COVID-19 is clearly linked to emphysema and chronic bronchitis at different stages of the disease, our understanding of the precise interaction between microbial infections during COPD, particularly with SARS-CoV-2 in the lungs, remains inadequate. Therefore, it is crucial to understand the host-pathogen relationship from the clinician's perspective in order to effectively manage COPD. This article aims to provide a comprehensive overview of the subject matter to assist clinicians in their efforts to improve the treatment and management of COPD, especially in light of the COVID-19 pandemic.

[ARDS Diagnostics and Treatment after the Coronavirus Pandemic - Everything as it was?]

ARDS is a syndrome that can develop as a result of various underlying diseases. For a long time, the prevailing belief was that the course of the disease was comparable regardless of the underlying disease. However, even before the COVID-19 pandemic, it was suspected that there were different manifestations that could be treated more individually and thus reduce the high mortality rate of ARDS, which has remained unchanged for years. The various findings on the heterogeneity of the course of the disease in COVID-related ARDS appear to confirm these assumptions. It is therefore to be expected that the diagnosis and treatment of non-COVID-related ARDS will also have to be individualised according to such phenotypes in the future. However, as long as the effectiveness of such strategies has not been proven in clinical trials, the current recommendations for ARDS therapy will remain valid for the time being. However, the adjustments already formulated in this context to individual pathophysiological conditions with regard to respiratory mechanics, ventilation-perfusion distribution and possible cardiac dysfunction should be made more meticulously than has usually been the case to date.

Exploring the Potential Long-term Impact of SARS-CoV-2 on Protein Misfolding and Amyloid-related Conditions

The long-term impact of the COVID-19 pandemic concerns risk to human health, particularly its potential association with protein misfolding and amyloidosis. This review article explores the causality relationship between SARS-CoV-2 infection, and protein misfolding, leading to amyloid-related conditions. It delves into the mechanisms by which viral proteins may accelerate amyloid formation, exacerbating post-infection complications, including neurological sequelae. Drawing from interdisciplinary research and clinical observations, the potential links between COVID-19, vaccination, and amyloidosis, emphasize the importance of understanding the longterm effect of post-COVID symptoms. This review examines the potential role of COVID-19-related proteins in the formation of amyloid in other related proteins of amyloidosis.

The Implications of the Pandemic with Covid-19 in the Glycemic Control of People with Type 2 Diabetes

Introduction

The COVID-19 lockdown influenced the glycemic control and other metabolic parameters in people with type 1 and 2 diabetes mellitus.

Objective

To study the effects of COVID-19 lockdown on glycemic control in people with type 2 diabetes mellitus (T2DM).

Material and Methods

Our study group included 120 Romanian people with T2DM from both urban and rural areas. We employed a structured questionnaire with multiple-choice to collect data about DM management during lockdown, the interaction with their diabetologist, the access to treatment, and what other factors influenced their DM management during the lockdown.

Results

We did not observe an increase of numbers of hyper or hypoglycemia during the restriction period in people with T2DM. The number of glycemic imbalances was higher in people treated with insulin than those with oral antidiabetics (OAD) (p=0.003, X2=8.91). Regarding the causes of imbalances, we did not obtain a significant difference during the restriction period, neither between patients following treatment with insulin nor with OAD. On the contrary, we observed that only 26.7% of people with T2DM managed to maintain their weight or lost weight vs 73.3% patients who gained several extra kg (p<0.001, X2=52.26).

Conclusion

The findings of this study have demonstrated that in people with T2DM, the COVID-19 lockdown determines better glycemic control among patients treated with OAD compared to those treated with insulin therapy. Anxiety, stress, and emotions were the main reasons that led to the increase in glycemic values of these patients. Also, most patients have gained weight either due to lack of physical activity or due to stress.

Severity of oxidative stress as a hallmark in COVID-19 patients

INTRODUCTION

Understanding the mechanisms and identifying effective treatments for the COVID-19 outbreak are imperative. Therefore, this study aimed to assess the antioxidant status and oxidative stress parameters as potential pivotal mechanisms in asymptomatic, non-severe, and severe COVID-19 patients.

METHODS

This study is a case-control study that was performed on patients referred to the Persian Gulf Martyrs Hospital of Bushehr University of Medical Sciences, Bushehr, Iran, from May 2021 to September 2021. A total of 600 COVID-19 patients (non-severe and severe group) and 150 healthy volunteers of the same age and sex were selected during the same period. On the first day of hospitalization, 10 ml of venous blood was taken from subjects. Then, hematological, biochemical, serological, antioxidant and oxidative stress parameters were determined.

RESULTS

Our results indicated that ESR, CRP, AST, ALT, and LDH significantly augmented in the severe group as compared to the non-severe and normal groups (P ≤ 0.05). It was observed that the levels of FRAP, G6PD activity, and SOD activity significantly reduced in the non-severe patients in comparison with the severe and normal groups (P ≤ 0.05). We found that MDA content and NO metabolite markedly increased in severe patients as compared to the non-severe group.

CONCLUSIONS

Taken together, it seems that the balance between antioxidants and oxidants was disturbed in COVID-19 patients in favor of oxidant markers. In addition, this situation caused more aggravation in severe patients as compared to the non-severe group.

Effects of plank exercise on respiratory capacity, physical fitness, and immunocytes in older adults

Plank is a readily accessible form of exercise that can benefit individuals of various fitness levels. However, its effectiveness in older individuals has not been conclusively established. Specifically, its impact on respiratory function, physical fitness, and immunocytes in them has not been thoroughly verified. The study encompassed participants with an average age of 64.33±1.98 years. All participants were randomly assigned to either the control group (COG) or the plank exercise group (PXG). The plank exercise was conducted 3 days a week for 12 weeks. While the values in the COG deteriorated, the PXG showed significant improvements in several parameters. Forced expiratory volume in one second and peak expiratory flow increased by approximately 27% and 16%, respectively, in the PXG, demonstrating significant differences (P<0.001) between the two groups. Additionally, VO2max, grip strength, and sit-ups increased by about 12%, 18%, and 42% in the PXG. Notably, innate immunocytes, such as NK cells, increased by approximately 30% in the PXG. For adaptive immunocytes, including CD3+ T cells, CD4+ T cells, and CD8+ T cells, there were notable increases of around 18%, 19%, and 28%, respectively, in the PXG. These findings underline significant differences (P<0.001) between the two groups. This study provides confirmation that engaging in plank exercise can enhance the function of immunocytes, while also improving respiratory capacity and physical fitness in older adults.

COVID-19-associated liver injury: Adding fuel to the flame

COVID-19 is mainly characterized by respiratory disorders and progresses to multiple organ involvement in severe cases. With expansion of COVID-19 and SARS-CoV-2 research, correlative liver injury has been revealed. It is speculated that COVID-19 patients exhibited abnormal liver function, as previously observed in the SARS and MERS pandemics. Furthermore, patients with underlying diseases such as chronic liver disease are more susceptible to SARS-CoV-2 and indicate a poor prognosis accompanied by respiratory symptoms, systemic inflammation, or metabolic diseases. Therefore, COVID-19 has the potential to impair liver function, while individuals with preexisting liver disease suffer from much worse infected conditions. COVID-19 related liver injury may be owing to direct cytopathic effect, immune dysfunction, gut-liver axis interaction, and inappropriate medication use. However, discussions on these issues are infancy. Expanding research have revealed that angiotensin converting enzyme 2 (ACE2) expression mediated the combination of virus and target cells, iron metabolism participated in the virus life cycle and the fate of target cells, and amino acid metabolism regulated immune response in the host cells, which are all closely related to liver health. Further exploration holds great significance in elucidating the pathogenesis, facilitating drug development, and advancing clinical treatment of COVID-19-related liver injury. This article provides a review of the clinical and laboratory hepatic characteristics in COVID-19 patients, describes the etiology and impact of liver injury, and discusses potential pathophysiological mechanisms.

Using Scientific Articles on COVID-19 to Introduce the Nature of Scientific Knowledge to Medical Students

It has been argued that, as evidence-based medicine emerged in the 1990s, healthcare practitioners are required to partake in more intricate and elaborate cognitive processes. As a result, knowing the characteristics and constraints of scientific knowledge - i.e., an advanced understanding of the Nature of Scientific Knowledge (NOSK) - has become progressively imperative. In this paper, we discuss snapshots of the research on SARS-CoV-2 that may be used in order to illustrate aspects of NOSK to medical students and how they may be introduced within teaching interventions.

A microfluidic biosensor architecture for the rapid detection of COVID-19

The lack of enough diagnostic capacity to detect severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) has been one of the major challenges in the control the 2019 COVID pandemic; this led to significant delay in prompt treatment of COVID-19 patients or accurately estimate disease situation. Current methods for the diagnosis of SARS-COV-2 infection on clinical specimens (e.g. nasal swabs) include polymerase chain reaction (PCR) based methods, such as real-time reverse transcription (rRT) PCR, real-time reverse transcription loop-mediated isothermal amplification (rRT-LAMP), and immunoassay based methods, such as rapid antigen test (RAT). These conventional PCR methods excel in sensitivity and specificity but require a laboratory setting and typically take up to 6 h to obtain the results whereas RAT has a low sensitivity (typically at least 3000 TCID50/ml) although with the results with 15 min. We have developed a robust micro-electro-mechanical system (MEMS) based impedance biosensor fit for rapid and accurate detection of SARS-COV-2 of clinical samples in the field with minimal training. The biosensor consisted of three regions that enabled concentrating, trapping, and sensing the virus present in low quantities with high selectivity and sensitivity in 40 min using an electrode coated with a specific SARS-COV-2 antibody cross-linker mixture. Changes in the impedance value due to the binding of the SARS-COV-2 antigen to the antibody will indicate positive or negative result. The testing results showed that the biosensor's limit of detection (LoD) for detection of inactivated SARS-COV-2 antigen in phosphate buffer saline (PBS) was as low as 50 TCID50/ml. The biosensor specificity was confirmed using the influenza virus while the selectivity was confirmed using influenza polyclonal sera. Overall, the results showed that the biosensor is able to detect SARS-COV-2 in clinical samples (swabs) in 40 min with a sensitivity of 26 TCID50/ml.

The Effect of Select SARS-CoV-2 N-Linked Glycan and Variant of Concern Spike Protein Mutations on C-Type Lectin-Receptor-Mediated Infection

The SARS-CoV-2 virion has shown remarkable resilience, capable of mutating to escape immune detection and re-establishing infectious capabilities despite new vaccine rollouts. Therefore, there is a critical need to identify relatively immutable epitopes on the SARS-CoV-2 virion that are resistant to future mutations the virus may accumulate. While hACE2 has been identified as the receptor that mediates SARS-CoV-2 susceptibility, it is only modestly expressed in lung tissue. C-type lectin receptors like DC-SIGN can act as attachment sites to enhance SARS-CoV-2 infection of cells with moderate or low hACE2 expression. We developed an easy-to-implement assay system that allows for the testing of SARS-CoV-2 trans-infection. Using our assay, we assessed how SARS-CoV-2 Spike S1-domain glycans and spike proteins from different strains affected the ability of pseudotyped lentivirions to undergo DC-SIGN-mediated trans-infection. Through our experiments with seven glycan point mutants, two glycan cluster mutants and four strains of SARS-CoV-2 spike, we found that glycans N17 and N122 appear to have significant roles in maintaining COVID-19's infectious capabilities. We further found that the virus cannot retain infectivity upon the loss of multiple glycosylation sites, and that Omicron BA.2 pseudovirions may have an increased ability to bind to other non-lectin receptor proteins on the surface of cells. Taken together, our work opens the door to the development of new therapeutics that can target overlooked epitopes of the SARS-CoV-2 virion to prevent C-type lectin-receptor-mediated trans-infection in lung tissue.

Spray-Dried Inhalable Microparticles Combining Remdesivir and Ebselen against SARS-CoV-2 Infection

There is a continuous effort to develop efficient treatments for coronavirus disease 2019 (COVID-19) and other viral respiratory diseases. Among the different strategies, inhaled treatment is considered one of the most logical and efficient approaches to treating COVID-19, as the causative "SARS-CoV-2 virus RNA" predominantly infects the respiratory tract. COVID-19 treatments initially relied on repurposed drugs, with a few additional strategies developed during the last two years, and all of them are based on monotherapy. However, drug combinations have been found to be more effective than monotherapy in other viral diseases such as HIV, influenza, and hepatitis C virus. In the case of SARS-CoV-2 infection, in vitro studies have shown synergistic antiviral activity combining remdesivir with ebselen, an organoselenium compound. Therefore, these drug combinations could ensure better therapeutic outcomes than the individual agents. In this study, we developed a dry powder formulation containing remdesivir and ebselen using a spray-drying technique and used L-leucine as an aerosolization enhancer. The prepared dry powders were spherical and crystalline, with a mean particle size between 1 and 3 µm, indicating their suitability for inhalation. The emitted dose (ED) and fine particle fraction (FPF) of remdesivir- and ebselen-containing dry powders were ~80% and ~57% when prepared without L-leucine. The ED as well as the FPF significantly increased with values of >86% and >67%, respectively, when L-leucine was incorporated. More importantly, the single and combinational dry powder of remdesivir and ebselen showed minimal cytotoxicity (CC50 > 100 μM) in Calu-3 cells, retaining their anti-SARS-CoV-2 properties (EC50 2.77 to 18.64 μM). In summary, we developed an inhalable dry powder combination of remdesivir and ebselen using a spray-drying technique. The spray-dried inhalable microparticles retained their limited cytotoxicity and specific antiviral properties. Future in vivo studies are needed to verify the potential use of these remdesivir/ebselen combinational spray-dried inhalable microparticles to block the SARS-CoV-2 replication in the respiratory tract.

An IgM-like inhalable ACE2 fusion protein broadly neutralizes SARS-CoV-2 variants

Many of the currently available COVID-19 vaccines and therapeutics are not effective against newly emerged SARS-CoV-2 variants. Here, we developed the metallo-enzyme domain of angiotensin converting enzyme 2 (ACE2)-the cellular receptor of SARS-CoV-2-into an IgM-like inhalable molecule (HH-120). HH-120 binds to the SARS-CoV-2 Spike (S) protein with high avidity and confers potent and broad-spectrum neutralization activity against all known SARS-CoV-2 variants of concern. HH-120 was developed as an inhaled formulation that achieves appropriate aerodynamic properties for rodent and monkey respiratory system delivery, and we found that early administration of HH-120 by aerosol inhalation significantly reduced viral loads and lung pathology scores in male golden Syrian hamsters infected by the SARS-CoV-2 ancestral strain (GDPCC-nCoV27) and the Delta variant. Our study presents a meaningful advancement in the inhalation delivery of large biologics like HH-120 (molecular weight (MW) ~ 1000 kDa) and demonstrates that HH-120 can serve as an efficacious, safe, and convenient agent against SARS-CoV-2 variants. Finally, given the known role of ACE2 in viral reception, it is conceivable that HH-120 has the potential to be efficacious against additional emergent coronaviruses.

Silica quantum dots; an optical nanosensing approach for trace detection of pesticides in environmental and biological samples

Both the environment and human health have suffered as a result of excessive and irrational pesticide use. The human body is vulnerable to a wide range of illnesses brought on by prolonged exposure to or intake of food contaminated with pesticide residues, including immunological and hormonal abnormalities and the development of certain tumors. Sensors based on nanoparticles stand out from more conventional spectrophotometry analytical methods due to their low detection limits, high sensitivity, and ease of use; that is why the demand for simple, fast, and less expensive sensing methods increases daily and presents myriad uses. Such demands are fulfilled by employing paper-based analytical devices having intrinsic properties. The presented work reports an on-site, easy-to-handle, and disposable paper-based sensing device for performing fast screening along with readout from a smartphone. The fabricated device utilizes luminescent silica quantum dots, immobilized into a paper cellulose matrix, and the resonance energy transfer phenomenon is employed. The silica quantum dots probes were fabricated from citric acid and, by undergoing physical adsorption, were confined on the nitrocellulose substrate in small wax-traced spots. The silica quantum dots were excited by smartphone ultraviolet LED, acting as an energy source and for capturing the image. The obtained LOD is 0.054 μM, and the coefficient of variation is less than 6.1%, comparable to the result obtained by UV-Visible and fluorometric analysis under similar experimental conditions. In addition, high reproducibility (≥9.8%) and high recovery ≥90% were obtained in spiked blood samples. The fabricated sensor sensitively detected pesticides giving a LOD of 2.5 ppm along with the development of yellow color within a short period of 5 min. The sensor functions well when sophisticated instrumentation is not accessible. The presented work shows the potential of the paper strip for the on-site detection of pesticides in biological and environmental samples.

Dissecting the Interrelationship between COVID-19 and Diabetes Mellitus

COVID-19 disease, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has led to enormous morbidity and mortality worldwide. After gaining entry into the human host, the virus initially infects the upper and lower respiratory tract, subsequently invading multiple organs, including the pancreas. While on one hand, diabetes mellitus (DM) is a significant risk factor for severe COVID-19 infection and associated death, recent reports have shown the onset of DM in COVID-19-recovered patients. SARS-CoV-2 infiltrates the pancreatic islets and activates stress response and inflammatory signaling pathways, impairs glucose metabolism, and consequently leads to their death. Indeed, the pancreatic autopsy samples of COVID-19 patients reveal the presence of SARS-CoV-2 particles in β-cells. The current review describes how the virus enters the host cells and activates an immunological response. Further, it takes a closer look into the interrelationship between COVID-19 and DM with the aim to provide mechanistic insights into the process by which SARS-CoV-2 infects the pancreas and mediates dysfunction and death of endocrine islets. The effects of known anti-diabetic interventions for COVID-19 management are also discussed. The application of mesenchymal stem cells (MSCs) as a future therapy for pancreatic β-cells damage to reverse COVID-19-induced DM is also emphasized.

Respiratory issues in patients with multiple sclerosis as a risk factor during SARS-CoV-2 infection: a potential role for exercise

Coronavirus disease-2019 (COVID-19) is associated with cytokine storm and is characterized by acute respiratory distress syndrome (ARDS) and pneumonia problems. The respiratory system is a place of inappropriate activation of the immune system in people with multiple sclerosis (MS), and this may cause damage to the lung and worsen both MS and infections.The concerns for patients with multiple sclerosis are because of an enhance risk of infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The MS patients pose challenges in this pandemic situation, because of the regulatory defect of autoreactivity of the immune system and neurological and respiratory tract symptoms. In this review, we first indicate respiratory issues associated with both diseases. Then, the main mechanisms inducing lung damages and also impairing the respiratory muscles in individuals with both diseases is discussed. At the end, the leading role of physical exercise on mitigating respiratory issues inducing mechanisms is meticulously evaluated.

Cardiovascular risk and the COVID-19 pandemic: A retrospective observational study in a population of healthcare professionals

BACKGROUND AND AIM

To contain the spread of COVID-19, many countries imposed several restrictive measures, leading to radical changes in daily life behaviors. Healthcare workers experienced additional stress due to the increased risk of contagion, possibly causing an increase in unhealthy habits. We investigated changes in cardiovascular (CV) risk assessed by the SCORE-2 in a healthy population of healthcare workers during the COVID-19 pandemic; an analysis by subgroups was also conducted (sportspeople vs sedentary subjects).

METHODS AND RESULTS

We compared medical examination and blood tests in a population of 264 workers aged over 40, performed yearly before (T0) and during the pandemic (T1, T2). We found a significant increase in the average CV risk, according to SCORE-2, during the follow-up in our healthy population, with a shift from a mean low-moderate risk profile at T0 (2.35%) to a mean high-risk profile at T2 (2.80%). Furthermore, in sedentary subjects was observed a greater and early increase in SCORE-2 compared to sportspeople.

CONCLUSIONS

Since 2019, we observed an increase in CV risk profile in a healthy population of healthcare workers, particularly in sedentary subjects, highlighting the need to reassess SCORE-2 every year to promptly treat high-risk subjects, according to the latest Guidelines.

Identification of a 1.4-kb-Long Sequence Located in the nsp12 and nsp13 Coding Regions of SARS-CoV-2 Genomic RNA That Mediates Efficient Viral RNA Packaging

The specific packaging of the viral RNA genome into virus particles is an essential step in the replication cycle of coronaviruses (CoVs). Using a single-cycle, replicable severe acute respiratory syndrome CoV-2 (SARS-CoV-2) mutant, we demonstrated the preferential packaging of the SARS-CoV-2 genomic RNA into purified virus particles. Furthermore, based on the sequence of an efficiently packaged defective interfering RNA of SARS-CoV, a closely related CoV, that was generated after serial passages of SARS-CoV in cell culture, we designed a series of replication-competent SARS-CoV-2 minigenome RNAs to identify the specific viral RNA region that is important for SARS-CoV-2 RNA packaging into virus particles. We showed that a 1.4-kb-long sequence, derived from the nsp12 and nsp13 coding regions of the SARS-CoV-2 genomic RNA, is required for the efficient packaging of SARS-CoV-2 minigenome RNA into SARS-CoV-2 particles. In addition, we also showed that the presence of possibly the entire 1.4-kb-long sequence is important for the efficient packaging of SARS-CoV-2 RNA. Our findings highlight the differences between the RNA packaging sequence identified in SARS-CoV-2, a Sarbecovirus, and the packaging signal of mouse hepatitis virus (MHV), an Embecovirus, which is a 95-nt-long sequence located at the nsp15 coding region of MHV genomic RNA. Collectively, our data imply that both the location and the sequence/structural features of the RNA element(s) that drives the selective and efficient packaging of viral genomic RNA are not conserved among the subgenera Embecovirus and Sarbecovirus within the Betacoronavirus genus. IMPORTANCE Elucidating the mechanism of SARS-CoV-2 RNA packaging into virus particles is important for the rational design of antiviral drugs that inhibit this vital step in the replication cycle of CoVs. However, our knowledge about the RNA packaging mechanism in SARS-CoV-2, including the identification of the viral RNA region important for SARS-CoV-2 RNA packaging, is limited, primarily due to the logistical challenges of handing SARS-CoV-2 in biosafety level 3 (BSL3) facilities. Our study, using a single-cycle, replicable SARS-CoV-2 mutant, which can be handled in a BSL2 lab, demonstrated the preferential packaging of full-length SARS-CoV-2 genomic RNA into virus particles and identified a specific 1.4-kb-long RNA region in SARS-CoV-2 genomic RNA that is required for the efficient packaging of SARS-CoV-2 RNA into virus particles. The information generated in our study could be valuable for clarifying the mechanisms of SARS-CoV-2 RNA packaging and for the development of targeted therapeutics against SARS-CoV-2 and other related CoVs.

Microbiome and intestinal pathophysiology in post-acute sequelae of COVID-19

Long COVID, also known for post-acute sequelae of COVID-19, describes the people who have the signs and symptoms that continue or develop after the acute COVID-19 phase. Long COVID patients suffer from an inflammation or host responses towards the virus approximately 4 weeks after initial infection with the SARS CoV-2 virus and continue for an uncharacterized duration. Anyone infected with COVID-19 before could experience long-COVID conditions, including the patients who were infected with SARS CoV-2 virus confirmed by tests and those who never knew they had an infection early. People with long COVID may experience health problems from different types and combinations of symptoms over time, such as fatigue, dyspnea, cognitive impairments, and gastrointestinal (GI) symptoms (e.g., nausea, vomiting, diarrhea, decreased or loss of appetite, abdominal pain, and dysgeusia). The critical role of the microbiome in these GI symptoms and long COVID were reported in clinical patients and experimental models. Here, we provide an overall view of the critical role of the GI tract and microbiome in the development of long COVID, including the clinical GI symptoms in patients, dysbiosis, viral-microbiome interactions, barrier function, and inflammatory bowel disease patients with long COVID. We highlight the potential mechanisms and possible treatment based on GI health and microbiome. Finally, we discuss challenges and future direction in the long COVID clinic and research.

Towards Understanding Long COVID: SARS-CoV-2 Strikes the Host Cell Nucleus

Despite what its name suggests, the effects of the COVID-19 pandemic causative agent "Severe Acute Respiratory Syndrome Coronavirus-2" (SARS-CoV-2) were not always confined, neither temporarily (being long-term rather than acute, referred to as Long COVID) nor spatially (affecting several body systems). Moreover, the in-depth study of this ss(+) RNA virus is defying the established scheme according to which it just had a lytic cycle taking place confined to cell membranes and the cytoplasm, leaving the nucleus basically "untouched". Cumulative evidence shows that SARS-CoV-2 components disturb the transport of certain proteins through the nuclear pores. Some SARS-CoV-2 structural proteins such as Spike (S) and Nucleocapsid (N), most non-structural proteins (remarkably, Nsp1 and Nsp3), as well as some accessory proteins (ORF3d, ORF6, ORF9a) can reach the nucleoplasm either due to their nuclear localization signals (NLS) or taking a shuttle with other proteins. A percentage of SARS-CoV-2 RNA can also reach the nucleoplasm. Remarkably, controversy has recently been raised by proving that-at least under certain conditions-, SARS-CoV-2 sequences can be retrotranscribed and inserted as DNA in the host genome, giving rise to chimeric genes. In turn, the expression of viral-host chimeric proteins could potentially create neo-antigens, activate autoimmunity and promote a chronic pro-inflammatory state.

Association between leukocyte telomere length and COVID-19 severity

Background

Inter-individual variations in the clinical manifestations of SARS-CoV-2 infection are among the challenging features of COVID-19. The known role of telomeres in cell proliferation and immune competency highlights their possible function in infectious diseases. Variability in telomere length is an invaluable parameter in the heterogeneity of the clinical presentation of diseases.

Result

In this study, our aim was to investigate the possible association between leukocyte telomere length (LTL) and COVID-19 severity. LTL was measured in 100 patients with moderate and severe forms of COVID-19 using the quantitative PCR (q-PCR) method. Statistical analysis confirmed a strong inverse correlation between relative LTL and COVID-19 severity.

Conclusions

These findings suggest that LTL can be a useful parameter for predicting disease severity in patients, as individuals with short telomeres may have a higher risk of developing severe COVID-19.

Supplementary Information

The online version contains supplementary material available at 10.1186/s43042-023-00415-z.

Effects of Covid-19 on the autonomic nervous system in elite athletes assessed by heart rate variability

Introduction

Covid-19 is a viral airway and systemic infection which can negatively affect the function of the autonomic nervous system. Cardiovascular autonomic function is essential for peak athletic performance. The aim of this study was to assess the effects of a Covid-19 disease on the autonomic nervous system of German elite athletes using heart rate variability (HRV).

Methods

60 elite athletes (aged 22.88 ± 4.71 years) were recruited, 30 of whom had undergone a Covid-19 disease. Heart rate (HR), blood pressure (BP) and heart rate variability (HRV) were measured during rest and during an orthostatic challenge.

Results

At rest and after orthostatic stress blood pressure and the root mean square of successive differences (RMSDD) were significantly lower in Covid-19 athletes (COV) than in control athletes (CON) (p = 0.002 and p = 0.004, respectively); heart rate was significantly higher (p = 0.001). COV showed a significantly greater reduction in blood pressure and elevation of heart rate than CON, but the change in RMSSD did not differ significantly during the orthostatic challenge.

Conclusion

These results show a change in cardiac parasympathetic activity and cardiovascular autonomic function in German elite athletes after Covid-19. These findings further the understanding of effects of the Covid-19 disease on the cardiovascular physiology in athletes. Heart rate variability may be a helpful tool in the return-to-play assessment of elite athletes.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11332-023-01067-7.

Post-COVID-19 Spondylodiscitis: A Case Study and Review of the Literature

COVID-19 is currently a major health problem, leading to respiratory, cardiovascular and neurological complications, with additional morbidity and mortality. Spinal infections are rare, representing around 1% of all bone infections and comprising less than 2 per 10,000 of all hospitalizations in tertiary care centers. Spondylodiscitis is a complex disease, with challenging diagnosis and management. We report the case of a 45-year-old man, non-smoker hospitalized for severe COVID-19 disease with respiratory failure. Post-COVID-19, in the 8th week after discharge, he was diagnosed by magnetic resonance imaging with spondylodiscitis, but etiology was not confirmed by microbiological investigations. Antibiotics were used, considering the identification of MRSA from cultures of pleural fluid and nasal swab, but surgical intervention was not provided. Clinic, biologic and imagistic were improved, but rehabilitation and long term follow up are necessary. We concluded that spondylodiscitis with spinal abscess is a rare but severe complication post-COVID-19 disease, due to dysbalanced immune response related to the respiratory viral infection, endothelial lesions, hypercoagulation and bacterial superinfection.

Molecular Analysis of SARS-CoV-2 Spike Protein-Induced Endothelial Cell Permeability and vWF Secretion

Coronavirus disease COVID-19, which is caused by severe acute respiratory syndrome coronavirus SARS-CoV-2, has become a worldwide pandemic in recent years. In addition to being a respiratory disease, COVID-19 is a 'vascular disease' since it causes a leaky vascular barrier and increases blood clotting by elevating von Willebrand factor (vWF) levels in the blood. In this study, we analyzed in vitro how the SARS-CoV-2 spike protein S1 induces endothelial cell (EC) permeability and its vWF secretion, and the underlying molecular mechanism for it. We showed that the SARS-CoV-2 spike protein S1 receptor-binding domain (RBD) is sufficient to induce endothelial permeability and vWF-secretion through the angiotensin-converting enzyme (ACE)2 in an ADP-ribosylation factor (ARF)6 activation-dependent manner. However, the mutants, including those in South African and South Californian variants of SARS-CoV-2, in the spike protein did not affect its induced EC permeability and vWF secretion. In addition, we have identified a signaling cascade downstream of ACE2 for the SARS-CoV-2 spike protein-induced EC permeability and its vWF secretion by using pharmacological inhibitors. The knowledge gained from this study could be useful in developing novel drugs or repurposing existing drugs for treating infections of SARS-CoV-2, particularly those strains that respond poorly to the existing vaccines.

Investigation of SARS-CoV-2 using RT-PCR in vaginal swab samples of female patients with a diagnosis of severe COVID-19

OBJECTIVE

It is important to determine the presence of SARS-CoV-2 in the vaginal fluid samples of reproductive-aged women with severe disease during the acute stage of the disease and to determine the risks of transmission by sexual or vertical transmission.

MATERIAL AND METHODS

Adult women with confirmed severe COVID-19 who were admitted to Ankara City Hospital intensive care unit (ICU) between December 1st, 2020, and January 1st, 2021, were enrolled in the study. Vaginal swab samples were collected within 48 h in the ICU using Dacron or rayon swabs and tested for SARS-CoV-2 using reverse transcription real-time polymerase chain reaction (RT PCR).

RESULTS

Thirty women of reproductive age were included in the study, five (16.7%) of whom were pregnant. The mean age was 44.9 (±10.5) years. The most common symptoms were headache (100%), muscle soreness (86.7%), cough (76.7%), fever (60%), and nausea and vomiting (20%). Nineteen (63.3%) patients had underlying medical conditions. The time interval from obtaining vaginal swab samples to admission to the ICU was 48 h. The time between vaginal sampling and PCR positivity ranged from 2 to 18 days. SARS-CoV-2 was not detected in any vaginal samples.

CONCLUSION

Our study showed that women with severe COVID-19 did not have SARS-CoV-2 in their vaginal fluids. Investigation of the presence of SARS-CoV-2 in vaginal secretions may help in determining the risks of sexual transmission and vertical transmission from mother to baby. Information on this subject is still limited. Larger studies on comprehensive biological samples are needed.

Does the Thymus Index Predict COVID-19 Severity?

BACKGROUND

The COVID-19 (coronavirus disease 2019) pandemic is a global health emergency that is straining health care resources. Identifying patients likely to experience severe illness would allow more targeted use of resources. This study aimed to investigate the association between the thymus index (TI) on thorax computed tomography (CT) and prognosis in patients with COVID-19.

METHODS

A multicenter, cross-sectional, retrospective study was conducted between March 17 and June 30, 2020, in patients with confirmed COVID-19. The patients' clinical history and laboratory data were collected after receiving a signed consent form. Four experienced radiologists who were blinded to each other and patient data performed image evaluation. The appearance of the thymus was assessed in each patient using 2 published systems, including the TI and thymic morphology. Exclusion criteria were lack of initial diagnostic thoracic CT, previous sternotomy, pregnancy, and inappropriate images for thymic evaluation. A total of 2588 patients with confirmed COVID-19 and 1231 of these with appropriate thoracic CT imaging were included. Multivariable analysis was performed to predict the risk of severe disease and mortality.

RESULTS

The median age was 45 (interquartile range, 33-58) years; 52.2% were male. Two hundred forty-nine (20.2%) patients had severe disease, and 60 (4.9%) patients died. Thymus index was significantly associated with mortality and severe disease (odds ratios, 0.289 [95% confidence interval, 0.141-0.588; P = 0.001]; and 0.266 [95% confidence interval, 0.075-0.932; P = 0.038]), respectively. Perithymic lymphadenopathy on CT imaging had a significantly strong association with grades of TI in patients with severe disease and death ( V = 0.413 P = 0.017; and V = 0.261 P = 0.002, respectively). A morphologically assessable thymus increased the probability of survival by 17-fold and the absence of severe disease by 12-fold.

CONCLUSION

Assessment of the thymus in patients with COVID-19 may provide useful prognostic data for both disease severity and mortality.

Insights into the Scenario of SARS-CoV-2 Infection in Male Reproductive Toxicity

COVID-19 has become a significant public health concern that has catastrophic consequences for society. Some preliminary evidence suggests that the male reproductive system may be an infection target for SARS-CoV-2. SARS-CoV-2 may be transmitted sexually, according to preliminary research. Testicular cells exhibit a high level of the angiotensin-converting enzyme 2 (ACE2) receptor, which enhances the entry of the SARS-CoV-2 into host cells. Some instances of COVID-19 have been documented to exhibit hypogonadism during the acute stage. Furthermore, systemic inflammatory reactions triggered by SARS-CoV-2 infection may cause oxidative stress (OS), which has been shown to have profoundly deleterious consequences on testicular functioning. This work gives a clear picture of how COVID-19 may affect male reproductive systems and calls attention to the many unanswered questions about the mechanisms by which this virus can be linked to men's health and fertility.

The Role of Immunity in the Pathogenesis of SARS-CoV-2 Infection and in the Protection Generated by COVID-19 Vaccines in Different Age Groups

This study aims to review the available data regarding the central role of immunity in combating SARS-CoV-2 infection and in the generation of protection by vaccination against COVID-19 in different age groups. Physiologically, the immune response and the components involved in it are variable, both functionally and quantitatively, in neonates, infants, children, adolescents, and adults. These immunological differences are mirrored during COVID-19 infection and in the post-vaccination period. The outcome of SARS-CoV-2 infection is greatly dependent on the reaction orchestrated by the immune system. This is clearly obvious in relation to the clinical status of COVID-19 infection, which can be symptomless, mild, moderate, or severe. Even the complications of the disease show a proportional pattern in relation to the immune response. On the contrary, the commonly used anti-COVID-19 vaccines generate protective humoral and cellular immunity. The magnitude of this immunity and the components involved in it are discussed in detail. Furthermore, many of the adverse effects of these vaccines can be explained on the basis of immune reactions against the different components of the vaccines. Regarding the appropriate choice of vaccine for different age groups, many factors have to be considered. This is a cornerstone, particularly in the following age groups: 1 day to 5 years, 6 to 11 years, and 12 to 17 years. Many factors are involved in deciding the route, doses, and schedule of vaccination for children. Another important issue in this dilemma is the hesitancy of families in making the decision about whether to vaccinate their children. Added to these difficulties is the choice by health authorities and governments concerning whether to make children's vaccination compulsory. In this respect, although rare and limited, adverse effects of vaccines in children have been detected, some of which, unfortunately, have been serious or even fatal. However, to achieve comprehensive control over COVID-19 in communities, both children and adults have to be vaccinated, as the former group represents a reservoir for viral transmission. The understanding of the various immunological mechanisms involved in SARS-CoV-2 infection and in the preparation and application of its vaccines has given the sciences a great opportunity to further deepen and expand immunological knowledge. This will hopefully be reflected positively on other diseases through gaining an immunological background that may aid in diagnosis and therapy. Humanity is still in continuous conflict with SARS-CoV-2 infection and will be for a while, but the future is expected to be in favor of the prevention and control of this disease.

Hypoxia modeling techniques: A review

Hypoxia is the main cause and effect of a large number of diseases, including the most recent one facing the world, the coronavirus disease (COVID-19). Hypoxia is divided into short-term, long-term, and periodic, it can be the result of diseases, climate change, or living and traveling in the high mountain regions of the world. Since each type of hypoxia can be a cause and a consequence of various physiological changes, the methods for modeling these hypoxias are also different. There are many techniques for modeling hypoxia under experimental conditions. The most common animal for modeling hypoxia is a rat. Hypoxia models (hypoxia simulations) in rats are a tool to study the effect of various conditions on the oxygen supply of the body. These models can provide a necessary information to understand hypoxia and also provide effective treatment, highlighting the importance of various reactions of the body to hypoxia. The main parameters when choosing a model should be reproducibility and the goal that the scientist wants to achieve. Hypoxia in rats can be reproduced both ways exogenously and endogenously. The reason for writing this review was the aim to systematize the models of rats available in the literature in order to facilitate their selection by scientists. The relative strengths and limitations of each model need to be identified and understood in order to evaluate the information obtained from these models and extrapolate these results to humans to develop the necessary generalizations. Despite these problems, animal models have been and remain vital to understanding the mechanisms involved in the development and progression of hypoxia. The eligibility criteria for the selected studies was a comprehensive review of the methods and results obtained from the studies. This made it possible to make generalizations and give recommendations on the application of these methods. The review will assist scientists in choosing an appropriate hypoxia simulation method, as well as assist in interpreting the results obtained with these methods.

Ligand-based discovery of coronavirus main protease inhibitors using MACAW molecular embeddings

Ligand-based drug design methods are thought to require large experimental datasets to become useful for virtual screening. In this work, we propose a computational strategy to design novel inhibitors of coronavirus main protease, M^pro. The pipeline integrates publicly available screening and binding affinity data in a two-stage machine-learning model using the recent MACAW embeddings. Once trained, the model can be deployed to rapidly screen large libraries of molecules in silico. Several hundred thousand compounds were virtually screened and 10 of them were selected for experimental testing. From these 10 compounds, 8 showed a clear inhibitory effect on recombinant M^pro, with half-maximal inhibitory concentration values (IC₅₀) in the range 0.18–18.82 μM. Cellular assays were also conducted to evaluate cytotoxic, haemolytic, and antiviral properties. A promising lead compound against coronavirus M^pro was identified with dose-dependent inhibition of virus infectivity and minimal toxicity on human MRC-5 cells.

Effect of COVID-19 infection on the erectile function

OBJECTIVE

It has been understood that COVID-19, which has become a global pandemic in a short time, is a disease affecting multiple organs and systems. Some of the organs and systems affected by the disease also play a role in the pathophysiology of erectile dysfunction (ED), which led us to consider the possible effects of the disease on the erectile function. In this study, we aimed to evaluate changes in the erectile functions of patients with COVID-19 among those that had previously diagnosed with mild and moderate ED in our urology outpatient clinic.

MATERIAL AND METHODS

Eighty-one patients aged 18-65 years who were confirmed to have COVID-19 were included in the study. According to disease severity, these patients were divided into two groups as mild (non-hospitalized, n = 60) and moderate (hospitalized but did not require intensive care, n = 21). The patients' pre- and post-disease scores in the five-item International Index of Erectile Function (IIEF-5) ​​and hormone panel results were compared.

RESULTS

The changes in the IIEF-5 scores of the patients from the pre-disease to the post-disease period were statistically significant for both the mild and moderate groups (p < 0.05). When these changes were compared between the mild and moderate groups, the difference was not statistically significant (p = 0.156). There was also no statistically significant change in the testosterone, follicle-stimulating, luteinizing, and prolactin hormone levels before and after the disease.

CONCLUSION

In this study, we determined that SARS-CoV-2 infection caused deterioration in existing ED in sexually active male individuals, regardless of the severity of the disease.

Progressive interstitial lung disease in hypomyopathic dermatomyositis in the COVID-19 pandemic: A case report

BACKGROUND

Clinically amyopathic dermatomyositis (CADM) is characterized by typical skin lesions with no (amyopathic) or subclinical (hypomyopathic) evidence of muscle involvement. Patients with CADM may also develop rapidly progressive interstitial lung disease (ILD), and have a poor prognosis. However, the diagnosis of rapidly progressive ILD faces a challenge during the severe acute respiratory syndrome coronavirus 2 pandemic. Severe acute respiratory syndrome and ground-glass attenuation on a chest computed tomography scan are the presenting features in both conditions.

CASE PRESENTATION

A 45-year-old woman with amyopathic dermatomyositis had acute onset of fever and dyspnea in February 2020. She had abnormal lung findings on CT scan. Polymerase chain reaction testing for SARS-CoV-2 was not available at that time. Chest CT revealed non-specific manifestations that could be either the signs of ILD or SARS-CoV-2 infection. Antiviral therapy was initiated with oseltamivir. Three days later, she had erythema on face, palm, and back. The ratio of lactate dehydrogenase (LDH) isoenzyme 3 to total LDH was elevated. The ratio of LDH isoenzyme 1 to total LDH was declined. Therefore, she was transferred to the rheumatology ward for further treatment. However, she died from respiratory failure 2 weeks later.

CONCLUSIONS

We speculate that the altered LDH isoenzyme pattern may be an early biomarker for co-occurrence of CADM and ILD.

Elective Colorectal Surgery Service Provision during SARS-CoV-2 Pandemic

The SARS-Cov-2 pandemic and its immediate public health impact has caused severe disruption of regular medical care provision. The morbimortality of other diseases continues to affect people regardless of the viral infection. Indeed, it would be reasonable to assume that they have been aggravated by the period of most restrictive public health measures that were adopted against the virus. Recovery and maintenance of healthcare provision is required despite the ongoing threat. Therefore, it is critical to resume services in a structured and safe way, otherwise greater harm could come to our patients and to ourselves. The present article proposes to be a broad guide to the recovery and maintenance of elective outpatient, surgical and lower endoscopic services, aiding the colorectal surgeon in identifying risks, assessing their multiple dimensions, and implementing risk management strategies in a pragmatic and efficacious way.

Human Cytomegalovirus Infection of Epithelial Cells Increases SARS-CoV-2 Superinfection by Upregulating the ACE2 Receptor

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), has caused widespread morbidity and mortality since its onset in late 2019. Here, we demonstrate that prior infection with human cytomegalovirus (HCMV) substantially increases infection with SARS-CoV-2 in vitro. HCMV is a common herpesvirus carried by 40%-100% of the population, which can reactivate in the lung under inflammatory conditions, such as those resulting from SARS-CoV-2 infection. We show in both endothelial and epithelial cell types that HCMV infection upregulates ACE2, the SARS-CoV-2 cell entry receptor. These observations suggest that HCMV reactivation events in the lung of healthy HCMV carriers could exacerbate SARS-CoV-2 infection and subsequent COVID-19 symptoms. This effect could contribute to the disparity of disease severity seen in ethnic minorities and those with lower socioeconomic status, due to their higher CMV seroprevalence. Our results warrant further clinical investigation as to whether HCMV infection influences the pathogenesis of SARS-CoV-2.

Glutathione deficiency in the pathogenesis of SARS-CoV-2 infection and its effects upon the host immune response in severe COVID-19 disease

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that causes coronavirus disease 19 (COVID-19) has numerous risk factors leading to severe disease with high mortality rate. Oxidative stress with excessive production of reactive oxygen species (ROS) that lower glutathione (GSH) levels seems to be a common pathway associated with the high COVID-19 mortality. GSH is a unique small but powerful molecule paramount for life. It sustains adequate redox cell signaling since a physiologic level of oxidative stress is fundamental for controlling life processes via redox signaling, but excessive oxidation causes cell and tissue damage. The water-soluble GSH tripeptide (γ-L-glutamyl-L-cysteinyl-glycine) is present in the cytoplasm of all cells. GSH is at 1-10 mM concentrations in all mammalian tissues (highest concentration in liver) as the most abundant non-protein thiol that protects against excessive oxidative stress. Oxidative stress also activates the Kelch-like ECH-associated protein 1 (Keap1)-Nuclear factor erythroid 2-related factor 2 (Nrf2)-antioxidant response element (ARE) redox regulator pathway, releasing Nrf2 to regulate the expression of genes that control antioxidant, inflammatory and immune system responses, facilitating GSH activity. GSH exists in the thiol-reduced and disulfide-oxidized (GSSG) forms. Reduced GSH is the prevailing form accounting for >98% of total GSH. The concentrations of GSH and GSSG and their molar ratio are indicators of the functionality of the cell and its alteration is related to various human pathological processes including COVID-19. Oxidative stress plays a prominent role in SARS-CoV-2 infection following recognition of the viral S-protein by angiotensin converting enzyme-2 receptor and pattern recognition receptors like toll-like receptors 2 and 4, and activation of transcription factors like nuclear factor kappa B, that subsequently activate nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) expression succeeded by ROS production. GSH depletion may have a fundamental role in COVID-19 pathophysiology, host immune response and disease severity and mortality. Therapies enhancing GSH could become a cornerstone to reduce severity and fatal outcomes of COVID-19 disease and increasing GSH levels may prevent and subdue the disease. The life value of GSH makes for a paramount research field in biology and medicine and may be key against SARS-CoV-2 infection and COVID-19 disease.

Histologic, viral, and molecular correlates of heart disease in fatal COVID-19

Cardiac manifestations are common in severe COVID-19. This study compared the histologic, viral, and molecular findings in cardiac tissue in fatal COVID-19 (n = 11) and controls (n = 11). In situ hybridization (SARS-CoV2 RNA) and immunohistochemistry for viral proteins and the host response were quantified for the samples and compared with qRTPCR and Western blot data. Control hearts showed a high resident population of macrophages that had variable ACE2 expression. Cardiac ACE2 expression was 10× greater in the heart tissues of cases and controls with obesity or type II diabetes. Multifocal endothelial cell swelling and degeneration, perivascular edema plus microvascular thrombi were unique to the cases. SARS-CoV2 RNA and nucleocapsid protein were rarely detected in situ in any COVID-19 heart. However, in each case abundant SARS-CoV-2 spike protein was evident. Co-expression experiments showed that the spike protein localized mostly to the ACE2+ interstitial macrophages/pericytes that were activated as evidenced by increased IL6 and TNFα expression. Western blots confirmed the presence of the viral spike protein, but not the nucleocapsid protein, in the cardiac homogenates. The intercalated disc proteins connexin 43, the primary cardiac gap junction protein, and Na_V1.5, the predominant cardiac sodium channel, each showed marked lateral migration in the myocytes in the cases, which would increase the risk of reentrant arrhythmias. It is concluded that the viral spike protein, endocytosed by macrophages/pericytes, can induce a myocarditis with the possibility of conduction dysfunction due to abnormal localization of key intercalated disc proteins.

Determinants of Cause-Specific Mortality and Loss of Independence in Older Patients following Hospitalization for COVID-19: The GeroCovid Outcomes Study

Hospitalization for acute SARS-CoV-2 infection confers an almost five-fold higher risk of post-discharge, all-cause mortality compared to controls from the general population. A negative impact on the functional autonomy of older patients, especially in cases of severe disease and prolonged hospitalization, has been recently described. However, little is known about the determinants of cause-specific mortality and loss of independence (LOI) in the activities of daily living (ADL) following COVID-19 hospitalization. Thus, the current prospective, multicenter study is aimed at identifying the determinants of post-discharge cause-specific mortality and the loss of autonomy in at least one ADL function. Older patients hospitalized for a SARS-CoV-2 infection were consecutively enrolled in an e-Registry from 1 March 2020, until 31 December 2020. After at least six months from discharge, patients were extensively re-evaluated according to a common protocol at the outpatient clinic of eight tertiary care Italian hospitals. Of 193 patients [109 (56.4%) men, mean age 79.9 ± 9.1 years], 43 (22.3%) died during follow-up. The most common causes of death were cardiovascular diseases (46.0%), respiratory failure (26.5%), and gastrointestinal and genitourinary diseases (8.8% each). Pre-morbid ADLs qualified as an independent mortality risk factor [adjusted HR 0.77 (95%CI: 0.63–0.95)]. Of 132 patients, 28 (21.2%) lost their independence in at least one ADL. The adjusted risk of LOI declined with a lower frailty degree [aOR 0.03 (95%CI: 0.01–0.32)]. In conclusion, at long-term follow-up after hospitalization for acute SARS-CoV-2 infection, more than 40% of older patients died or experienced a loss of functional independence compared to their pre-morbid condition. Given its high prevalence, the loss of functional independence after hospitalization for COVID-19 could be reasonably included among the features of the “Long COVID-19 syndrome” of older patients.

A Case Series of Spinal Infections Following COVID-19: A Delayed Complication

Spinal infection in the form of tuberculous vertebral osteomyelitis or pyogenic spondylodiscitis is a commonly associated state of an immunodeficient host from various pathologies. For example, secondary infections can be seen following coronavirus disease 2019 (COVID-19). We report three cases of different forms of spinal infections that occurred as delayed complications to recent COVID-19 infection. The first case is a 60-year-old female who was diagnosed with an epidural abscess presenting with severe back pain and bilateral lower limb weakness. The second case is an elderly male who was diagnosed with L3/L4 spondylodiscitis and presented with predominantly back pain and minimal leg symptom. The final case is a young female who was diagnosed with severe T5 tuberculous spondylitis and presented with a complete sensory and motor deficit from T5 below. All patients showed good improvement after surgery and antibiotic therapy. Patients treated for COVID-19 are at risk of spinal infection development due to multiple pathophysiologies. Treatment of these various forms of spinal infection remains difficult, and we encourage physicians to be vigilant for the development of these complications post COVID-19 infection.