The Role of the Immune System on the Cardiac Complications Observed in SARS-CoV-2

Abstract An acute respiratory syndrome caused by SARS-CoV2 was declared a pandemic by the World Health Organization. Current data in the world and in Brazil show that approximately 40% of patients who died have some type of cardiac comorbidity. There are also robust reports showing an increase in IL-6 / IL-1B / TNF-alpha and the presence of lymphopenia in patients with COVID-19. Our team and others have shown that increased cytokines are the link between arrhythmias/Left ventricular dysfunction and the immune system in different diseases. In addition, it has been well demonstrated that lymphopenia can not only be a good marker, but also a factor that causes heart failure. Thus, the present review focused on the role of the immune system upon the cardiac alterations observed in the SARS-CoV2 infection. Additionally, it was well described that SARS-CoV-2 is able to infect cardiac cells. Therefore, here it will be reviewed in deep.

Is Ozone therapy an adjunct treatment for SARS-CoV-2 / COVID-19 infection?

Abstract Up to today, there is no specific treatment against SARS-CoV-2 / COVID-19 infection; there the necessity to search for alternatives that help patients with COVID-19. The objective of this study was to review the use of ozone therapy as adjunct treatment for SARS-CoV-2 / COVID-19 infection, highlighting the mechanisms of action, forms of application and current clinical evidence. A systematic review was conducted in electronic databases, searching the terminology Ozone "or" Ozone therapy "and" SARS-CoV-2 or COVID-19 or Coronavirus. Results: nineteen studies were included; ten were editorials, comments, brief reports or reviews, and nine clinical studies. We found that ozone therapy could be favorable for treating patients infected with SARS-CoV-2 / COVID-19, through a direct antiviral effect, regulation of oxidative stress, immunomodulation and improvement of oxygen metabolism. Patients who were treated with ozone therapy responded favorably; therefore, ozone therapy appears to be a promising treatment for patients infected with SARS-CoV-2 / COVID-19. Its mechanism of action justifies its use as an adjuvant therapy; however, scientific evidence is based on case series and clinical trials are necessary to corroborate its effectiveness and safety.

[The differential diagnosis of pulmonary infiltrates in cancer patients during the outbreak of the 2019 novel coronavirus disease].

Objective: To investigate the principles of differential diagnosis of pulmonary infiltrates in cancer patients during the outbreak of novel coronavirus (2019-nCoV) by analyzing one case of lymphoma who presented pulmonary ground-glass opacities (GGO) after courses of chemotherapy. Methods: Baseline demographics and clinicopathological data of eligible patients were retrieved from medical records. Information of clinical manifestations, history of epidemiology, lab tests and chest CT scan images of visiting patients from February 13 to February 28 were collected. Literatures about pulmonary infiltrates in cancer patients were searched from databases including PUBMED, EMBASE and CNKI. Results: Among the 139 cancer patients who underwent chest CT scans before chemotherapy, pulmonary infiltrates were identified in eight patients (5.8%), five of whom were characterized with GGOs in lungs. 2019-nCoV nuclear acid testing was performed in three patients and the results were negative. One case was a 66-year-old man who was diagnosed with non-Hodgkin lymphoma and underwent CHOP chemotherapy regimen. His chest CT scan image displayed multiple GGOs in lungs and the complete blood count showed decreased lymphocytes. This patient denied any contact with confirmed/suspected cases of 2019-nCoV infection, fever or other respiratory symptoms. Considering the negative result of nuclear acid testing, this patient was presumptively diagnosed with viral pneumonia and an experiential anti-infection treatment had been prescribed for him. Conclusions: The 2019 novel coronavirus disease (COVID-19) complicates the clinical scenario of pulmonary infiltrates in cancer patients. The epidemic history, clinical manifestation, CT scan image and lab test should be taken into combined consideration. The 2019-nCoV nuclear acid testing might be applied in more selected patients. Active anti-infection treatment and surveillance of patient condition should be initiated if infectious disease is considered.

Coronaviruses exploit a host cysteine-aspartic protease for replication.

Highly pathogenic coronaviruses, including severe acute respiratory syndrome coronavirus 2 (refs. 1,2) (SARS-CoV-2), Middle East respiratory syndrome coronavirus3 (MERS-CoV) and SARS-CoV-1 (ref. 4), vary in their transmissibility and pathogenicity. However, infection by all three viruses results in substantial apoptosis in cell culture5-7 and in patient tissues8-10, suggesting a potential link between apoptosis and pathogenesis of coronaviruses. Here we show that caspase-6, a cysteine-aspartic protease of the apoptosis cascade, serves as an important host factor for efficient coronavirus replication. We demonstrate that caspase-6 cleaves coronavirus nucleocapsid proteins, generating fragments that serve as interferon antagonists, thus facilitating virus replication. Inhibition of caspase-6 substantially attenuates lung pathology and body weight loss in golden Syrian hamsters infected with SARS-CoV-2 and improves the survival of mice expressing human DPP4 that are infected with mouse-adapted MERS-CoV. Our study reveals how coronaviruses exploit a component of the host apoptosis cascade to facilitate virus replication.

The Japanese Health System and its coping mechanisms against COVID-19 / O Sistema de Saúde japonês e seus mecanismos de enfrentamento à COVID-19

Introdução: apesar de ser o país de maior média de idade no mundo, o Japão tem se destacado no combate à pandemia da COVID-19 (do inglês Coronavirus Disease 2019) ao apresentar reduzidas taxas de contaminação pelo vírus e de mortalidade. Objetivo: discutir acerca das estratégias em saúde adotadas pelo Japão diante da pandemia da doença da COVID-19, bem como avaliar os dados sobre contaminação e mortalidade japoneses em comparação com os outros quatro países com maior média de idade do mundo (Itália, Alemanha, Portugal e Espanha) e o Brasil. Metodologia: para avaliação das estratégias em saúde japonesas foi realizada busca nas bases de dados: PubMed, Cochrane e Scielo, utilizando-se combinação dos termos "Japão", "covid", "coronavirus" e "sistemas de saúde", nos idiomas Inglês, Espanhol e Português. Os dados de infecção da COVID-19 foram extraídos do site Our World in Data, correspondendo ao período de 25 de janeiro de 2020 a 30 de julho de 2020. Resultados: dentre as medidas adotadas pelo país no enfrentamento à pandemia, destacam-se o diagnóstico e resposta precoces à infecção, o rastreamento de contatos, o diagnóstico precoce e disponibilidade de cuidados intensivos para pacientes graves e estímulo a medidas comportamentais de distanciamento. Dentre os países analisados, o Japão apresenta as menores taxas de contaminação e mortalidade em termos absolutos pela COVID-19. Conclusões: medidas de distanciamento social, diagnóstico e tratamento precoces parecem ter contribuído para o sucesso no combate à COVID-19 no Japão. No período estudado, em milhão de habitantes, o Japão teve 6,13 casos de Covid, enquanto o Brasil apresentou 218,26 casos. Já no número de mortes confirmadas pela doença, o primeiro teve uma taxa de 0,23 enquanto o segundo de 5,16 casos por milhão de habitantes. É possível, a partir do conhecimento dessas medidas, buscar mecanismos semelhantes ao traçar políticas de saúde no enfrentamento de pandemias em outros países (AU)

Introduction: despite being the country with the highest average age globally, Japan has stood out in the fight against the COVID-19 (Coronavirus Disease 2019) pandemic by presenting low contamination rates by the virus and mortality. Objective: we aim to discuss the health strategies adopted by Japan in the face of the COVID-19 disease pandemic, as well as to evaluate data on Japanese contamination and mortality compared to the other four countries with the highest average age in the world (Italy, Germany, Portugal and Spain) and Brazil. Methodology: the search was carried out to evaluate Japanese health strategies by using the following databases: PubMed, Cochrane, and Scielo using a combination of the terms "Japan", "covid", "coronavirus" and "health systems" in English, Spanish and Portuguese. The COVID-19 infection data was extracted from the Our World in Data website, from January 25, 2020, to July 30, 2020. Results: Among the measures adopted by the country to face the pandemic, the early diagnosis and response to infection, contact tracing, early diagnosis and availability of intensive care for critically ill patients, and encouraging behavioral distancing measures stand out. Among the countries analyzed, Japan has the lowest rates of contamination and mortality in absolute terms by COVID-19. Conclusions: social distancing measures, early diagnosis, and treatment seem to have contributed to the success in combating COVID-19 in Japan. In the studied period, in a million inhabitants, Japan had 6.13 cases of covid while Brazil had 218.26 cases. As for the number of deaths confirmed by the disease, the first had a rate of 0.23 while the second had 5.16 cases per million inhabitants. Based on the knowledge of these measures, it is possible to seek similar mechanisms when designing health policies to face pandemics in other countries (AU)

Coronavirus - A Crippling Affliction to Humans.

Coronaviruses hold idiosyncratic morphological features and functionality. The members of this group have a remarkable capability of infecting both animals and humans. Inimitably, the replication of the RNA genome continues through the set of viral mRNA molecules. Coronaviruses received least attention until 2003 since they caused only minor respiratory tract illnesses. However, this changed exclusively with the introduction of zoonotic SARS-CoV in 2003. In 2012, MERS-CoV emerged and confirmed this group of viruses as the major causative agents of severe respiratory tract illness. Today, Coronavirus Disease 2019 (i.e., COVID-19) has turned out to be a chief health problem that causes a severe acute respiratory disorder in humans. Since the first identification of COVID-19 in December 2019 in Wuhan, China, this infection has devastatingly spread all around the globe leading to a crippling affliction for humans. The strain is known as the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), and WHO (the World Health Organization) has termed this new pandemic disease as Coronavirus Disease (COVID-19). COVID-19 is still spreading, with an estimated 136 million confirmed cases and more than 2.94 million deaths worldwide so far. In the current scenario, there is no particular treatment for COVID-19; however, remarkable efforts for immunization and vaccine development can be observed. Therefore, the execution of precautions and proper preventive measures are indispensable to minimize and control the community transmission of the virus. This review summarizes information related to the pathophysiology, transmission, symptoms, the host defense mechanism plus immunization and vaccine development against COVID-19 including the patents filed.

Coronaviruses.

The members of coronavirus family are facultative pathogens of birds and mammals, including men. From their first isolation 60 years ago, they caused smaller or larger epidemics mainly originating from China. The most recent pandemic quickly spreading worldwide has affected over 2,000,000 people. Keywords: coronavirus; epidemic; single strand vRNA.

Drug Combinations as a First Line of Defense against Coronaviruses and Other Emerging Viruses.

The world was unprepared for coronavirus disease 2019 (COVID-19) and remains ill-equipped for future pandemics. While unprecedented strides have been made developing vaccines and treatments for COVID-19, there remains a need for highly effective and widely available regimens for ambulatory use for novel coronaviruses and other viral pathogens. We posit that a priority is to develop pan-family drug cocktails to enhance potency, limit toxicity, and avoid drug resistance. We urge cocktail development for all viruses with pandemic potential both in the short term (<1 to 2 years) and longer term with pairs of drugs in advanced clinical testing or repurposed agents approved for other indications. While significant efforts were launched against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), in vitro and in the clinic, many studies employed solo drugs and had disappointing results. Here, we review drug combination studies against SARS-CoV-2 and other viruses and introduce a model-driven approach to assess drug pairs with the highest likelihood of clinical efficacy. Where component agents lack sufficient potency, we advocate for synergistic combinations to achieve therapeutic levels. We also discuss issues that stymied therapeutic progress against COVID-19, including testing of agents with low likelihood of efficacy late in clinical disease and lack of focus on developing virologic surrogate endpoints. There is a need to expedite efficient clinical trials testing drug combinations that could be taken at home by recently infected individuals and exposed contacts as early as possible during the next pandemic, whether caused by a coronavirus or another viral pathogen. The approach herein represents a proactive plan for global viral pandemic preparedness.

A Review of Human Coronaviruses' Receptors: The Host-Cell Targets for the Crown Bearing Viruses.

A novel human coronavirus prompted considerable worry at the end of the year 2019. Now, it represents a significant global health and economic burden. The newly emerged coronavirus disease caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is the primary reason for the COVID-19 global pandemic. According to recent global figures, COVID-19 has caused approximately 243.3 million illnesses and 4.9 million deaths. Several human cell receptors are involved in the virus identification of the host cells and entering them. Hence, understanding how the virus binds to host-cell receptors is crucial for developing antiviral treatments and vaccines. The current work aimed to determine the multiple host-cell receptors that bind with SARS-CoV-2 and other human coronaviruses for the purpose of cell entry. Extensive research is needed using neutralizing antibodies, natural chemicals, and therapeutic peptides to target those host-cell receptors in extremely susceptible individuals. More research is needed to map SARS-CoV-2 cell entry pathways in order to identify potential viral inhibitors.

Genomic Characterization of Diverse Bat Coronavirus HKU10 in Hipposideros Bats.

Bats have been identified as natural reservoirs of a variety of coronaviruses. They harbor at least 19 of the 33 defined species of alpha- and betacoronaviruses. Previously, the bat coronavirus HKU10 was found in two bat species of different suborders, Rousettus leschenaultia and Hipposideros pomona, in south China. However, its geographic distribution and evolution history are not fully investigated. Here, we screened this viral species by a nested reverse transcriptase PCR in our archived samples collected over 10 years from 25 provinces of China and one province of Laos. From 8004 bat fecal samples, 26 were found to be positive for bat coronavirus HKU10 (BtCoV HKU10). New habitats of BtCoV HKU10 were found in the Yunnan, Guangxi, and Hainan Provinces of China, and Louang Namtha Province in Laos. In addition to H. pomona, BtCoV HKU10 variants were found circulating in Aselliscus stoliczkanus and Hipposideros larvatus. We sequenced full-length genomes of 17 newly discovered BtCoV HKU10 strains and compared them with previously published sequences. Our results revealed a much higher genetic diversity of BtCoV HKU10, particularly in spike genes and accessory genes. Besides the two previously reported lineages, we found six novel lineages in their new habitats, three of which were located in Yunnan province. The genotypes of these viruses are closely related to sampling locations based on polyproteins, and correlated to bat species based on spike genes. Combining phylogenetic analysis, selective pressure, and molecular-clock calculation, we demonstrated that Yunnan bats harbor a gene pool of BtCoV HKU10, with H. pomona as a natural reservoir. The cell tropism test using spike-pseudotyped lentivirus system showed that BtCoV HKU10 could enter cells from human and bat, suggesting a potential interspecies spillover. Continuous studies on these bat coronaviruses will expand our understanding of the evolution and genetic diversity of coronaviruses, and provide a prewarning of potential zoonotic diseases from bats.

Kallikreins emerge as new regulators of viral infections.

Kallikrein-related peptidases (KLKs) or kallikreins have been linked to diverse (patho) physiological processes, such as the epidermal desquamation and inflammation, seminal clot liquefaction, neurodegeneration, and cancer. Recent mounting evidence suggests that KLKs also represent important regulators of viral infections. It is well-established that certain enveloped viruses, including influenza and coronaviruses, require proteolytic processing of their hemagglutinin or spike proteins, respectively, to infect host cells. Similarly, the capsid protein of the non-enveloped papillomavirus L1 should be proteolytically cleaved for viral uncoating. Consequently, extracellular or membrane-bound proteases of the host cells are instrumental for viral infections and represent potential targets for drug development. Here, we summarize how extracellular proteolysis mediated by the kallikreins is implicated in the process of influenza (and potentially coronavirus and papillomavirus) entry into host cells. Besides direct proteolytic activation of viruses, KLK5 and 12 promote viral entry indirectly through proteolytic cascade events, like the activation of thrombolytic enzymes that also can process hemagglutinin, while additional functions of KLKs in infection cannot be excluded. In the light of recent evidence, KLKs represent potential host targets for the development of new antivirals. Humanized animal models to validate their key functions in viral infections will be valuable.

SARS-CoV-2 Accessory Proteins in Viral Pathogenesis: Knowns and Unknowns.

There are still many unanswered questions concerning viral SARS-CoV-2 pathogenesis in COVID-19. Accessory proteins in SARS-CoV-2 consist of eleven viral proteins whose roles during infection are still not completely understood. Here, a review on the current knowledge of SARS-CoV-2 accessory proteins is summarized updating new research that could be critical in understanding SARS-CoV-2 interaction with the host. Some accessory proteins such as ORF3b, ORF6, ORF7a and ORF8 have been shown to be important IFN-I antagonists inducing an impairment in the host immune response. In addition, ORF3a is involved in apoptosis whereas others like ORF9b and ORF9c interact with cellular organelles leading to suppression of the antiviral response in infected cells. However, possible roles of ORF7b and ORF10 are still awaiting to be described. Also, ORF3d has been reassigned. Relevant information on the knowns and the unknowns in these proteins is analyzed, which could be crucial for further understanding of SARS-CoV-2 pathogenesis and to design strategies counteracting their actions evading immune responses in COVID-19.

Pathogenesis of Coronaviruses Through Human Monocytes and Tissue Macrophages.

Coronaviruses (CoVs) contribute significantly to the burden of respiratory diseases, frequently as upper respiratory tract infections. Recent emergence of novel coronaviruses in the last few decades has highlighted the potential transmission, disease, and mortality related to these viruses. In this literature review, we shall explore the disease-causing mechanism of the virus through human monocytes and macrophages. Common strains will be discussed; however, this review will center around coronaviruses responsible for epidemics, namely severe acute respiratory syndrome coronavirus (SARS-CoV)-1 and -2 and the Middle East Respiratory Syndrome Coronavirus (MERS-CoV). Macrophages are key players in the immune system and have been found to play a role in the pathogenesis of lethal coronaviruses. In physiology, they are white blood cells that engulf and digest cellular debris, foreign substances, and microbes. They play a critical role in innate immunity and help initiate adaptive immunity. Human coronaviruses utilize various mechanisms to undermine the innate immune response through its interaction with macrophages and monocytes. It is capable of entering immune cells through DPP4 (dipeptidyl-peptidase 4) receptors and antibody-dependent enhancement, delaying initial interferon response which supports robust viral replication. Pathogenesis includes triggering the production of overwhelming pro-inflammatory cytokines that attract other immune cells to the site of infection, which propagate prolonged pro-inflammatory response. The virus has also been found to suppress the release of anti-inflammatory mediators such as IL-10, leading to an aberrant inflammatory response. Elevated serum cytokines are also believed to contribute to pathological features seen in severe disease such as coagulopathy, acute lung injury, and multiorgan failure.

Revisión rápida: monitoreo de la presencia e infectividad del virus SARS-CoV-2 y otros coronavirus en aguas residuales.

Objetivo. Describir la evidencia sobre la presencia e infectividad de SARS-CoV-2 y otros coronavirus en aguas residuales y su potencial uso como herramienta de vigilancia epidemiológica. Material y métodos. Búsqueda de publicaciones en PubMed y medRxiv desde enero 2003 hasta el 8 de junio de 2020 de acuerdo con la guía de revisiones rápidas de Cochrane. Resultados. Se incluyeron 29 publicaciones. El ARN de SARS-CoV-2 no infectivo se encontró en agua residual hospitalaria, agua residual cruda, tratada y lodos de plantas de tratamiento. Los niveles cuantitativos de ARN viral en agua residual presentan relación con el número de casos de Covid-19. SARS-CoV-1 y otros coronavirus permanecieron infectivos en agua residual cruda hasta por dos días. Conclusiones. Hasta esta revisión no existe evidencia sobre la presencia de virus infectivos de SARS-CoV-2 en agua residual cruda o tratada. La cuantificación de ARN de SARS-CoV-2 en agua residual es útil para la vigilancia epidemiológica.

NLRP3 and Infections: ß-Amyloid in Inflammasome beyond Neurodegeneration.

Amyloid beta (Aß)-induced abnormal neuroinflammation is recognized as a major pathological feature of Alzheimer's disease (AD), which results in memory impairment. Research exploring low-grade systemic inflammation and its impact on the development and progression of neurodegenerative disease has increased. A particular research focus has been whether systemic inflammation arises only as a secondary effect of disease, or it is also a cause of pathology. The inflammasomes, and more specifically the NLRP3 inflammasome, are crucial components of the innate immune system and are usually activated in response to infection or tissue damage. Although inflammasome activation plays critical roles against various pathogens in host defense, overactivation of inflammasome contributes to the pathogenesis of inflammatory diseases, including acute central nervous system (CNS) injuries and chronic neurodegenerative diseases, such as AD. This review summarizes the current literature on the role of the NLRP3 inflammasome in the pathogenesis of AD, and its involvement in infections, particularly SARS-CoV-2. NLRP3 might represent the crossroad between the hypothesized neurodegeneration and the primary COVID-19 infection.