Nanotechnology based approaches for COVID-19: A Path forward

2021 ◽  
Vol 05 ◽  
Author(s):  
Suraj N. Mali ◽  
Amit P. Pratap
Keyword(s):  
Respiratory Infections ◽  
Viral Pathogenesis ◽  
Daily Basis ◽  
Surface Coatings ◽  
Host Cells ◽  
Google Scholar ◽  
Highly Pathogenic ◽  
Healthcare Burden ◽  
Current Review

Background: SARS-COV-2 causes the highly pathogenic disease called COVID-19. This disease leads to varieties of respiratory infections like pneumonia, cold, sneezing, etc. As this disease is being transmitted via airborne droplets, it is highly essential to use PPEs including masks, gloves, etc. This virus interacts with ACE2 receptor and further makes its entry into host cells leading viral pathogenesis. This viral is reported to be originated from Wuhan market, China. Despite of on-going efforts to control the spread, numbers of cases of COVID-19 are increasing on daily basis. Objective: This study aims to collect more information about aspects of nanotechnology based applications towards COVID-19 management. Methods: A systemic search has been carried out using PubMed, Google Scholar, CNKI, etc. for relevant studies. Results and Conclusions: Nanotechnology based various approaches like nanomedicines, surface coatings with nanoparticles, nanoparticle coated PPEs, and nanosensors could significantly reduce the healthcare burden by reducing the spread. Current review focuses on various approaches of nanotechnology during the pandemic COVID-19.

scholarly journals Innate Immunity Evasion Strategies of Highly Pathogenic Coronaviruses: SARS-CoV, MERS-CoV, and SARS-CoV-2

2021 ◽  
Vol 12 ◽  
Author(s):  
Jin-Yan Li ◽  
Zhi-Jian Zhou ◽  
Qiong Wang ◽  
Qing-Nan He ◽  
Ming-Yi Zhao ◽  
...  
Keyword(s):  
Immune Response ◽  
Pattern Recognition ◽  
Current Knowledge ◽  
Viral Pathogenesis ◽  
Host Cells ◽  
Highly Pathogenic ◽  
Cellular Processes ◽  
Antiviral Therapies ◽  
The Past ◽  
Human Coronaviruses

In the past two decades, coronavirus (CoV) has emerged frequently in the population. Three CoVs (SARS-CoV, MERS-CoV, SARS-CoV-2) have been identified as highly pathogenic human coronaviruses (HP-hCoVs). Particularly, the ongoing COVID-19 pandemic caused by SARS-CoV-2 warns that HP-hCoVs present a high risk to human health. Like other viruses, HP-hCoVs interact with their host cells in sophisticated manners for infection and pathogenesis. Here, we reviewed the current knowledge about the interference of HP-hCoVs in multiple cellular processes and their impacts on viral infection. HP-hCoVs employed various strategies to suppress and evade from immune response, including shielding viral RNA from recognition by pattern recognition receptors (PRRs), impairing IFN-I production, blocking the downstream pathways of IFN-I, and other evasion strategies. This summary provides a comprehensive view of the interplay between HP-hCoVs and the host cells, which is helpful to understand the mechanism of viral pathogenesis and develop antiviral therapies.

scholarly journals Complement Inactivation Strategy of Staphylococcus aureus Using Decay-Accelerating Factor and the Response of Infected HaCaT Cells

2021 ◽  
Vol 22 (8) ◽  
pp. 4015
Author(s):  
Kyoung Ok Jang ◽  
Youn Woo Lee ◽  
Hangeun Kim ◽  
Dae Kyun Chung
Keyword(s):  
Staphylococcus Aureus ◽  
Immune Cells ◽  
Respiratory Infections ◽  
Food Poisoning ◽  
Surface Expression ◽  
Host Cells ◽  
Hacat Cells ◽  
Decay Accelerating Factor ◽  
Ligand Expression ◽  
The Complement System

Staphylococcus aureus is a species of Gram-positive staphylococcus. It can cause sinusitis, respiratory infections, skin infections, and food poisoning. Recently, it was discovered that S. aureus infects epithelial cells, but the interaction between S. aureus and the host is not well known. In this study, we confirmed S. aureus to be internalized by HaCaT cells using the ESAT-6-like protein EsxB and amplified within the host over time by escaping host immunity. S. aureus increases the expression of decay-accelerating factor (CD55) on the surfaces of host cells, which inhibits the activation of the complement system. This mechanism makes it possible for S. aureus to survive in host cells. S. aureus, sufficiently amplified within the host, is released through the initiation of cell death. On the other hand, the infected host cells increase their surface expression of UL16 binding protein 1 to inform immune cells that they are infected and try to be eliminated. These host defense systems seem to involve the alteration of tight junctions and the induction of ligand expression to activate immune cells. Taken together, our study elucidates a novel aspect of the mechanisms of infection and immune system evasion for S. aureus.

scholarly journals Routes of Transmission of Newly Emerging SARS-CoV-2: A Systematic Review

2020 ◽  
pp. S18-S31 ◽  
Author(s):  
Mahmuda Yeasmin ◽  
Jannatut Tasnim ◽  
Arifa Akram ◽  
Md Abdullah Yusuf ◽  
AKM Shamsuzzaman ◽  
...  
Keyword(s):  
Systematic Review ◽  
Citation Index ◽  
Virus Disease ◽  
Scientific Basis ◽  
Atypical Pneumonia ◽  
Highly Pathogenic ◽  
Current Review ◽  
Corona Virus ◽  
Route Of Transmission ◽  
The World

Background: In December 2019, a novel corona virus (SARS-CoV-2) causes atypical pneumonia now known as “corona virus disease 2019” (COVID-19) emerged in Wuhan, China and spread rapidly throughout the world. Objective: The purpose of the present study was to identify the different plausible routes of transmission of SARS-CoV-2 into the human body. Methodology: We searched electronic databases (MEDLINE, EMBASE, Science Citation Index and Chinese database) checked documents and references. We included all the studies regarding potential routes of transmission of SARS-CoV-2. All reviewers independently screened titles and abstracts, assessed studies for inclusion, appraised quality, and extracted data. Result: SARS-CoV-2 has been found to have higher level of transmissibility than other two pathogenic CoVs. Sustained human to human transmission of SARS-CoV-2 has already been established though the exact route of transmission is yet to be determined. Similar to other CoVs, respiratory droplet and contact with contaminated surfaces are considered as principle route of transmission of SARS-CoV-2 whereas aerosol, feco-oral, perinatal, ocular surface and transfusion transmissions are the plausible route of spreading of this highly pathogenic CoVs. Conclusion: In the current review, we summarize the potential route of transmission of SARS-CoV-2 in the light of previous SARS-CoV and MERS-CoV outbreaks to solidify the scientific basis on which important decisions can be made. Bangladesh Journal of Infectious Diseases, April 2020;7(suppl_1):S18-S31

scholarly journals Inhibition of tRNA Synthetases Induces Persistence in Chlamydia

2020 ◽  
Vol 88 (4) ◽  
Author(s):  
Nathan D. Hatch ◽  
Scot P. Ouellette
Keyword(s):  
Host Cell ◽  
Chlamydia Pneumoniae ◽  
Respiratory Infections ◽  
Developmental State ◽  
Trna Synthetase ◽  
Host Cells ◽  
Host Immune System ◽  
Content Type ◽  
Ifn Γ

ABSTRACT Chlamydia trachomatis is the leading cause of bacterial sexually transmitted infections, and Chlamydia pneumoniae causes community-acquired respiratory infections. In vivo, the host immune system will release gamma interferon (IFN-γ) to combat infection. IFN-γ activates human cells to produce the tryptophan (Trp)-catabolizing enzyme indoleamine 2,3-dioxygenase (IDO). Consequently, there is a reduction in cytosolic Trp in IFN-γ-activated host cells. In evolving to obligate intracellular dependence, Chlamydia has significantly reduced its genome size and content, as it relies on the host cell for various nutrients. Importantly, C. trachomatis and C. pneumoniae are Trp auxotrophs and are starved for this essential nutrient when the human host cell is exposed to IFN-γ. To survive this, chlamydiae enter an alternative developmental state referred to as persistence. Chlamydial persistence is characterized by a halt in the division cycle, aberrant morphology, and, in the case of IFN-γ-induced persistence, Trp codon-dependent changes in transcription. We hypothesize that these changes in transcription are dependent on the particular amino acid starvation state. To investigate the chlamydial response mechanisms acting when other amino acids become limiting, we tested the efficacy of prokaryote-specific tRNA synthetase inhibitors, indolmycin and AN3365, to mimic starvation of Trp and leucine, respectively. We show that these drugs block chlamydial growth and induce changes in morphology and transcription consistent with persistence. Importantly, growth inhibition was reversed when the compounds were removed from the medium. With these data, we find that indolmycin and AN3365 are valid tools that can be used to mimic the persistent state independently of IFN-γ.

scholarly journals Conserved structural RNA domains in regions coding for cleavage site motifs in hemagglutinin genes of influenza viruses

2019 ◽  
Vol 5 (2) ◽  
Author(s):  
Alexander P Gultyaev ◽  
Mathilde Richard ◽  
Monique I Spronken ◽  
René C L Olsthoorn ◽  
Ron A M Fouchier
Keyword(s):  
Cleavage Site ◽  
Influenza A ◽  
Influenza Viruses ◽  
Host Cells ◽  
Influenza B ◽  
Structural Constraints ◽  
Highly Pathogenic ◽  
Stem Loop ◽  
Hairpin Loops ◽  
Rna Domains

Abstract The acquisition of a multibasic cleavage site (MBCS) in the hemagglutinin (HA) glycoprotein is the main determinant of the conversion of low pathogenic avian influenza viruses into highly pathogenic strains, facilitating HA cleavage and virus replication in a broader range of host cells. In nature, substitutions or insertions in HA RNA genomic segments that code for multiple basic amino acids have been observed only in the HA genes of two out of sixteen subtypes circulating in birds, H5 and H7. Given the compatibility of MBCS motifs with HA proteins of numerous subtypes, this selectivity was hypothesized to be determined by the existence of specific motifs in HA RNA, in particular structured domains. In H5 and H7 HA RNAs, predictions of such domains have yielded alternative conserved stem-loop structures with the cleavage site codons in the hairpin loops. Here, potential RNA secondary structures were analyzed in the cleavage site regions of HA segments of influenza viruses of different types and subtypes. H5- and H7-like stem-loop structures were found in all known influenza A virus subtypes and in influenza B and C viruses with homology modeling. Nucleotide covariations supported this conservation to be determined by RNA structural constraints that are stronger in the domain-closing bottom stems as compared to apical parts. The structured character of this region in (sub-)types other than H5 and H7 indicates its functional importance beyond the ability to evolve toward an MBCS responsible for a highly pathogenic phenotype.

Case 9

2020 ◽  
pp. 55-61
Author(s):  
Nicola Jones
Keyword(s):  
Intensive Care ◽  
Infection Control ◽  
Respiratory Infections ◽  
Rapid Assessment ◽  
Supportive Therapy ◽  
Respiratory Viruses ◽  
Rapid Diagnostics ◽  
Highly Pathogenic ◽  
Returning Travellers ◽  
Exposure History

Severe respiratory infections in returning travellers usually present to Emergency Departments and then require intensive care support. There needs to be early and rapid assessment, including a detailed travel and exposure history to assess the risk of highly pathogenic imported respiratory viruses with potential for transmission to healthcare workers. Such cases need to be managed with appropriate infection control precautions, rapid diagnostics, supportive therapy, and, in most cases, antivirals. A case returning from the Middle East is described

scholarly journals Phytonutrient and Nutraceutical Action against COVID-19: Current Review of Characteristics and Benefits

Nutrients ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 464
Author(s):  
Nitida Pastor ◽  
Maria Carmen Collado ◽  
Paolo Manzoni
Keyword(s):  
Viral Infections ◽  
Respiratory Infections ◽  
Therapeutic Agents ◽  
Therapeutic Interventions ◽  
Pharmacological Treatments ◽  
Complementary Treatment ◽  
Current Review ◽  
Immune Health

The trend toward using phytonutrients and/or nutraceuticals (P/Ns) with the aim of impacting immune health has increased in recent years. The main reason is that properties of P/Ns are associated with possible immunomodulating effects in the prevention and complementary treatment of viral diseases, including COVID-19 and other respiratory infections. In the present review, we assess the scientific plausibility of specific P/Ns for this purpose of preventative and therapeutic interventions against COVID-19, with an emphasis on safety, validity, and evidence of efficacy against other viruses. Five potential candidates have been identified after reviewing available studies (in silico, in vitro, and in vivo) in which certain flavonoids have demonstrated a potential for use as adjuvant therapeutic agents against viral infections, including COVID-19. As these are often better tolerated than pharmacological treatments, their use could be more widely considered if additional detailed studies can validate the existing evidence.

scholarly journals Heparan Sulfate-Dependent Enhancement of Henipavirus Infection

mBio ◽  
2015 ◽  
Vol 6 (2) ◽  
Author(s):  
Cyrille Mathieu ◽  
Kévin P. Dhondt ◽  
Marie Châlons ◽  
Stéphane Mély ◽  
Hervé Raoul ◽  
...  
Keyword(s):  
Heparan Sulfate ◽  
Anticoagulant Activity ◽  
Antiviral Treatment ◽  
Mammalian Species ◽  
Nipah Virus ◽  
Hendra Virus ◽  
Host Cells ◽  
Emerging Infections ◽  
Highly Pathogenic

ABSTRACTNipah virus and Hendra virus are emerging, highly pathogenic, zoonotic paramyxoviruses that belong to the genusHenipavirus. They infect humans as well as numerous mammalian species. Both viruses use ephrin-B2 and -B3 as cell entry receptors, and following initial entry into an organism, they are capable of rapid spread throughout the host. We have previously reported that Nipah virus can use another attachment receptor, different from its entry receptors, to bind to nonpermissive circulating leukocytes, thereby promoting viral dissemination within the host. Here, this attachment molecule was identified as heparan sulfate for both Nipah virus and Hendra virus. Cells devoid of heparan sulfate were not able to mediate henipavirustrans-infection and showed reduced permissivity to infection. Virus pseudotyped with Nipah virus glycoproteins bound heparan sulfate and heparin but no other glycosaminoglycans in a surface plasmon resonance assay. Furthermore, heparin was able to inhibit the interaction of the viruses with the heparan sulfate and to block cell-mediatedtrans-infection of henipaviruses. Moreover, heparin was shown to bind to ephrin-B3 and to restrain infection of permissive cellsin vitro. Consequently, treatment with heparin devoid of anticoagulant activity improved the survival of Nipah virus-infected hamsters. Altogether, these results reveal heparan sulfate as a new attachment receptor for henipaviruses and as a potential therapeutic target for the development of novel approaches against these highly lethal infections.IMPORTANCETheHenipavirusgenus includes two closely related, highly pathogenic paramyxoviruses, Nipah virus and Hendra virus, which cause elevated morbidity and mortality in animals and humans. Pathogenesis of both Nipah virus and Hendra virus infection is poorly understood, and efficient antiviral treatment is still missing. Here, we identified heparan sulfate as a novel attachment receptor used by both viruses to bind host cells. We demonstrate that heparin was able to inhibit the interaction of the viruses with heparan sulfate and to block cell-mediatedtrans-infection of henipaviruses. Moreover, heparin also bound to the viral entry receptor and thereby restricted infection of permissive cellsin vitro. Consequently, heparin treatment improved survival of Nipah virus-infected hamsters. These results uncover an important role of heparan sulfate in henipavirus infection and open novel perspectives for the development of heparan sulfate-targeting therapeutic approaches for these emerging infections.

scholarly journals Infections of People with Complement Deficiencies and Patients Who Have Undergone Splenectomy

2010 ◽  
Vol 23 (4) ◽  
pp. 740-780 ◽  
Author(s):  
Sanjay Ram ◽  
Lisa A. Lewis ◽  
Peter A. Rice
Keyword(s):  
Complement Activation ◽  
Antigen Processing ◽  
Respiratory Infections ◽  
Alternative Pathway ◽  
Fluid Phase ◽  
Host Cells ◽  
Medical Attention ◽  
Classical Pathway ◽  
Complement Components ◽  
Complement Pathways

SUMMARY The complement system comprises several fluid-phase and membrane-associated proteins. Under physiological conditions, activation of the fluid-phase components of complement is maintained under tight control and complement activation occurs primarily on surfaces recognized as “nonself” in an attempt to minimize damage to bystander host cells. Membrane complement components act to limit complement activation on host cells or to facilitate uptake of antigens or microbes “tagged” with complement fragments. While this review focuses on the role of complement in infectious diseases, work over the past couple of decades has defined several important functions of complement distinct from that of combating infections. Activation of complement in the fluid phase can occur through the classical, lectin, or alternative pathway. Deficiencies of components of the classical pathway lead to the development of autoimmune disorders and predispose individuals to recurrent respiratory infections and infections caused by encapsulated organisms, including Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae. While no individual with complete mannan-binding lectin (MBL) deficiency has been identified, low MBL levels have been linked to predisposition to, or severity of, several diseases. It appears that MBL may play an important role in children, who have a relatively immature adaptive immune response. C3 is the point at which all complement pathways converge, and complete deficiency of C3 invariably leads to severe infections, including those caused by meningococci and pneumococci. Deficiencies of the alternative and terminal complement pathways result in an almost exclusive predisposition to invasive meningococcal disease. The spleen plays an important role in antigen processing and the production of antibodies. Splenic macrophages are critical in clearing opsonized encapsulated bacteria (such as pneumococci, meningococci, and Escherichia coli) and intraerythrocytic parasites such as those causing malaria and babesiosis, which explains the fulminant nature of these infections in persons with anatomic or functional asplenia. Paramount to the management of patients with complement deficiencies and asplenia is educating patients about their predisposition to infection and the importance of preventive immunizations and seeking prompt medical attention.

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