Severe acute respiratory syndrome coronavirus 2 infection: Role of interleukin-6 and the inflammatory cascade

Early Results of an Infant Model of Orthotopic Cardiac Xenotransplantation

BACKGROUND

Genetically engineered porcine hearts may have an application for infants in need of a bridge to cardiac allotransplantation. The current animal model that resulted in 2 human applications has been validated in adult non-human primates only. We sought to create an infant animal model of life sustaining cardiac xenotransplantation to understand limitations specific to this age group.

METHODS

We performed 11 orthotopic cardiac xenotransplants from genetically modified infantile pigs into size-matched baboons (Papio spp). Porcine grafts were preserved using a modified Del Nido solution. Protocolized post-operative care and outcomes were tracked with invasive monitoring, echocardiogram, and serial chemistries (including a 7-cytokine panel).

RESULTS

Mean ischemic time was 52.1 +/- 13.9 min. All porcine hearts separated from bypass in normal sinus rhythm with normal systolic function documented by echocardiogram at chest closure and again at 24 h. In the first 48 post-operative hours, mean vasoactive inotropic score for the recipients was 9.6 +/- 3.5. Survival >3months was achieved in 6 animals. Five animals succumbed early (<7days) either due to errors in care (n=2) or pulmonary complications (n=3) confirmed on chest radiograph and necropsy. Cytokine levels objectively increased following xenograft implant but were not significantly different between survivors and non-survivors.

CONCLUSIONS

In a non-human primate model of infant orthotopic cardiac xenotransplantation, cardiac function does not hinder early peri-operative survival. Instead, pulmonary edema and pleural effusions in the setting of systemic inflammation preclude clinical progression. Targeted therapies are necessary to encourage prolonged survival.

Role of viruses in periodontitis: An extensive review of herpesviruses, human immunodeficiency virus, coronavirus-19, papillomavirus and hepatitis viruses

Periodontitis is the inflammation of the supporting structures around the dentition. Several microbial agents, mostly bacteria, have been identified as causative factors for periodontal disease. On the other hand, oral cavity is a rich reservoir for viruses since it contains a wide variety of cell types that can be targeted by viruses. Traditionally, the focus of research about the oral flora has been on bacteria because the most widespread oral diseases, like periodontitis and dental caries, are outcomes of bacterial infection. However, recently and especially after the emergence of coronavirus disease 2019, there is a growing tendency toward including viruses also into the scope of oral microbiome investigations. The global high prevalence of periodontitis and viral infections may point out to a concomitant or synergistic effect between the two. Although the exact nature of the mechanism still is not clearly understood, this could be speculated through the manipulation of the immune system by viruses; hence facilitating the furthermore colonization of the oral tissues by bacteria. This review provides an extensive and detailed update on the role of the most common viruses including herpes family (herpes simplex, varicella-zoster, Epstein-Barr, cytomegalovirus), Human papillomaviruses, Human immunodeficiency virus and severe acute respiratory syndrome coronavirus 2 in the initiation, progression and prognosis of periodontitis.

Impaired instructive and protective barrier functions of the endothelial cell glycocalyx pericellular matrix is impacted in COVID-19 disease

The aim of this study was to review the roles of endothelial cells in normal tissue function and to show how COVID-19 disease impacts on endothelial cell properties that lead to much of its associated symptomatology. This places the endothelial cell as a prominent cell type to target therapeutically in the treatment of this disorder. Advances in glycosaminoglycan analytical techniques and functional glycomics have improved glycosaminoglycan mimetics development, providing agents that can more appropriately target various aspects of the behaviour of the endothelial cell in-situ and have also provided polymers with potential to prevent viral infection. Thus, promising approaches are being developed to combat COVID-19 disease and the plethora of symptoms this disease produces. Glycosaminoglycan mimetics that improve endothelial glycocalyx boundary functions have promising properties in the prevention of viral infection, improve endothelial cell function and have disease-modifying potential. Endothelial cell integrity, forming tight junctions in cerebral cell populations in the blood-brain barrier, prevents the exposure of the central nervous system to circulating toxins and harmful chemicals, which may contribute to the troublesome brain fogging phenomena reported in cognitive processing in long COVID disease.

The role of Staphylococcus aureus in cystic fibrosis pathogenesis and clinico-microbiological interactions

Cystic fibrosis (CF) is a progressive and inherited disease that affects approximately 70000 individuals all over the world annually. A mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene serves as its defining feature. Bacterial infections have a significant impact on the occurrence and development of CF. In this manuscript, we discuss the role and virulence factors of Staphylococcus aureus as an important human pathogen with the ability to induce respiratory tract infections. Recent studies have reported S. aureus as the first isolated bacteria in CF patients. Methicillin-resistant Staphylococcus aureus (MRSA) pathogens are approximately resistant to all β-lactams. CF patients are colonized by MRSA expressing various virulence factors including toxins, and Staphylococcal Cassette Chromosome mec (SCCmec) types, and have the potential for biofilm formation. Therefore, variations in clinical outcomes will be manifested. SCCmec type II has been reported in CF patients more than in other SCCmec types from different countries. The small-colony variants (SCVs) as specific morphologic subtypes of S. aureus with slow growth and unusual properties can also contribute to persistent and difficult-to-treat infections in CF patients. The pathophysiology of SCVs is complicated and not fully understood. Patients with cystic fibrosis should be aware of the intrinsic risk factors for complex S. aureus infections, including recurring infections, physiological issues, or coinfection with P. aeruginosa.

Tocilizumab vs. baricitinib in hospitalized severe COVID-19 patients: results from a real-world cohort

BACKGROUND

Tocilizumab and baricitinib are recommended treatment options for hospitalized COVID-19 patients requiring oxygen support. Literature about its efficacy and safety in a head-to-head comparison is scarce.

METHODS

Hospitalized COVID-19 patients requiring oxygen were treated with tocilizumab or baricitinib additionally to dexamethasone. Tocilizumab was available from February till the 19th of September 2021 and baricitinib from 21st of September. The primary outcome was in-hospital mortality. Secondary outcome parameters were progression to mechanical ventilation (MV), length-of-stay (LOS) and potential side effects.

RESULTS

159 patients (tocilizumab 68, baricitinib 91) with a mean age of 60.5 years, 64% male were included in the study. Tocilizumab patients were admitted 1 day earlier, were in a higher WHO category at the time of inclusion and had a higher CRP level on admission and treatment initiation. Patients receiving Tocilizumab were treated with remdesivir more often and only patients in the baricitinib group were treated with monoclonal antibodies. Other characteristics did not differ significantly. In-hospital mortality (18% vs. 11%, p = 0.229), progression to MV (19% vs. 11%, p = 0.173) and LOS (13 vs. 12 days, p = 0.114) did not differ between groups. Side effects were equally distributed between groups, except ALAT elevation which was significantly more often observed in the tocilizumab group (43% vs. 25%, p = 0.021).

CONCLUSIONS

In-hospital mortality, progression to MV and LOS were not significantly different in patients treated with tocilizumab or baricitinib additionally to standard of care. Both drugs seem equally effective but further head-to-head trials are needed.

Liver Damage and COVID-19: At Least a “Two-Hit” Story in Systematic Review

COVID-19 pandemic waves have hit on our lives with pulmonary and, also, gastrointestinal symptoms. The latter also includes acute liver damage linked to direct SARS-CoV-2 action and/or drug-induced (DILI) in the frame of pre-existing chronic liver disease. We aimed to review literature data regarding liver damage during COVID-19. We conducted a systematic search on the main medical databases for original articles, reviews, meta-analyses, randomized clinical trials and case series using the following keywords and acronyms and their associations: liver disease, COVID-19, acute liver damage, drug-induced liver injury, antivirals. Acute liver damage due to SARS-CoV-2 infection is common among COVID-19 patients and is generally self-limiting. However, chronic hepatic diseases, such as metabolic-associated fatty liver disease (MAFLD), are associated with a less favorable prognosis, especially when alkaline phosphatases show a significant rise. Pathophysiology of COVID-19 liver damage is multifaceted and helps understand differences in liver derangement among patients. Thus, early recognition, monitoring and treatment of liver damage are crucial in these patients. In the frame of a not-ending pandemic sustained by SARS-CoV-2, it is crucial to recognize acute hepatic decompensation due to the virus and/or drugs used for COVID-19 treatment.

Hepatic Disorders and COVID-19: From Pathophysiology to Treatment Strategy

Following the SARS-CoV-2 outbreak and the subsequent development of the COVID-19 pandemic, organs such as the lungs, kidneys, liver, heart, and brain have been identified as priority organs. Liver diseases are considered a risk factor for high mortality from the COVID-19 pandemic. Besides, liver damage has been demonstrated in a substantial proportion of patients with COVID-19, especially those with severe clinical symptoms. Furthermore, antiviral medications, immunosuppressive drugs after liver transplantation, pre-existing hepatic diseases, and chronic liver diseases such as cirrhosis have also been implicated in SARS-CoV-2-induced liver injury. As a result, some precautions have been taken to prevent, monitor the virus, and avoid immunocompromised and susceptible individuals, such as liver and kidney transplant recipients, from being infected with SARS-CoV-2, thereby avoiding an increase in mortality. The purpose of this review was to examine the impairment caused by SARS-CoV-2 infection and the impact of drugs used during the pandemic on the mortality range and therefore the possibility of preventive measures in patients with liver disease.

Therapeutic and diagnostic applications of nanoparticles in the management of COVID-19: a comprehensive overview

In December 2019, Coronavirus Disease 2019 (COVID-19) was reported in Wuhan, China. Comprehensive strategies for quick identification, prevention, control, and remedy of COVID-19 have been implemented until today. Advances in various nanoparticle-based technologies, including organic and inorganic nanoparticles, have created new perspectives in this field. These materials were extensively used to control COVID-19 because of their specific attribution to preparing antiviral face masks, various safety sensors, etc. In this review, the most current nanoparticle-based technologies, applications, and achievements against the coronavirus were summarized and highlighted. This paper also offers nanoparticle preventive, diagnostic, and treatment options to combat this pandemic.