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1.
Int J Mol Sci ; 22(8)2021 Apr 08.
Article in English | MEDLINE | ID: covidwho-1299441

ABSTRACT

Pneumonia due to respiratory infection with most prominently bacteria, but also viruses, fungi, or parasites is the leading cause of death worldwide among all infectious disease in both adults and infants. The introduction of modern antibiotic treatment regimens and vaccine strategies has helped to lower the burden of bacterial pneumonia, yet due to the unavailability or refusal of vaccines and antimicrobials in parts of the global population, the rise of multidrug resistant pathogens, and high fatality rates even in patients treated with appropriate antibiotics pneumonia remains a global threat. As such, a better understanding of pathogen virulence on the one, and the development of innovative vaccine strategies on the other hand are once again in dire need in the perennial fight of men against microbes. Recent data show that the secretome of bacteria consists not only of soluble mediators of virulence but also to a significant proportion of extracellular vesicles-lipid bilayer-delimited particles that form integral mediators of intercellular communication. Extracellular vesicles are released from cells of all kinds of organisms, including both Gram-negative and Gram-positive bacteria in which case they are commonly termed outer membrane vesicles (OMVs) and membrane vesicles (MVs), respectively. (O)MVs can trigger inflammatory responses to specific pathogens including S. pneumonia, P. aeruginosa, and L. pneumophila and as such, mediate bacterial virulence in pneumonia by challenging the host respiratory epithelium and cellular and humoral immunity. In parallel, however, (O)MVs have recently emerged as auspicious vaccine candidates due to their natural antigenicity and favorable biochemical properties. First studies highlight the efficacy of such vaccines in animal models exposed to (O)MVs from B. pertussis, S. pneumoniae, A. baumannii, and K. pneumoniae. An advanced and balanced recognition of both the detrimental effects of (O)MVs and their immunogenic potential could pave the way to novel treatment strategies in pneumonia and effective preventive approaches.


Subject(s)
Bacteria/metabolism , Bacterial Outer Membrane/metabolism , Extracellular Vesicles/metabolism , Pneumonia, Bacterial/microbiology , Adaptive Immunity , Animals , Antigens, Bacterial/immunology , Bacteria/immunology , Bacterial Outer Membrane/immunology , Bacterial Vaccines/immunology , Host-Pathogen Interactions/immunology , Humans , Pneumonia, Bacterial/immunology , Pneumonia, Bacterial/prevention & control , Respiratory Mucosa/immunology , Respiratory Mucosa/microbiology , Respiratory Tract Infections/immunology , Respiratory Tract Infections/microbiology , Respiratory Tract Infections/prevention & control , Virulence
2.
PLoS Negl Trop Dis ; 15(3): e0009227, 2021 03.
Article in English | MEDLINE | ID: covidwho-1110082

ABSTRACT

Since its first emergence in 2012, cases of infection with Middle East respiratory syndrome coronavirus (MERS-CoV) have continued to occur. At the end of January 2020, 2519 laboratory confirmed cases with a case-fatality rate of 34.3% have been reported. Approximately 84% of human cases have been reported in the tropical region of Saudi Arabia. The emergence of MERS-CoV has highlighted need for a rapid and accurate assay to triage patients with a suspected infection in a timely manner because of the lack of an approved vaccine or an effective treatment for MERS-CoV to prevent and control potential outbreaks. In this study, we present two rapid and visual nucleic acid assays that target the MERS-CoV UpE and N genes as a panel that combines reverse transcription recombinase polymerase amplification with a closed vertical flow visualization strip (RT-RPA-VF). This test panel was designed to improve the diagnostic accuracy through dual-target screening after referencing laboratory testing guidance for MERS-CoV. The limit of detection was 1.2×101 copies/µl viral RNA for the UpE assay and 1.2 copies/µl viral RNA for the N assay, with almost consistent with the sensitivity of the RT-qPCR assays. The two assays exhibited no cross-reactivity with multiple CoVs, including the bat severe acute respiratory syndrome related coronavirus (SARSr-CoV), the bat coronavirus HKU4, and the human coronaviruses 229E, OC43, HKU1 and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Furthermore, the panel does not require sophisticated equipment and provides rapid detection within 30 min. This panel displays good sensitivity and specificity and may be useful to rapidly detect MERS-CoV early during an outbreak and for disease surveillance.


Subject(s)
Clinical Laboratory Techniques/methods , Coronavirus Infections/virology , Middle East Respiratory Syndrome Coronavirus/genetics , Molecular Diagnostic Techniques/methods , Coronavirus Infections/diagnosis , Coronavirus Infections/epidemiology , Humans , RNA, Viral/genetics , Real-Time Polymerase Chain Reaction/methods , Reverse Transcription , Saudi Arabia/epidemiology , Sensitivity and Specificity , Viral Nonstructural Proteins/genetics
3.
Curr Pharm Des ; 26(41): 5300-5309, 2020.
Article in English | MEDLINE | ID: covidwho-1073205

ABSTRACT

BACKGROUND: Previously human society has faced various unprecedented pandemics in the history and viruses have majorly held the responsibilities of those outbreaks. Furthermore, due to amplified global connection and speedy modernization, epidemic outbreaks caused by novel and re-emerging viruses signify potential risk to community health. Despite great advancements in immunization and drug discovery processes, various viruses still lack prophylactic vaccines and efficient antiviral therapies. Although, vaccine is a prophylaxes option, but it cannot be applied to infected patients, hence therapeutic interventions are urgently needed to control the ongoing global SARS- CoV-2 pandemic condition. To spot the novel antiviral therapy is of decisive importance and Mother Nature is an excellent source for such discoveries. METHODOLOGY: In this article, prompt high through-put virtual screening for vetting the best possible drug candidates from natural compounds' databases has been implemented. Herein, time tested rigorous multi-layered drug screening process to narrow down 66,969 natural compounds for the identification of potential lead(s) is implemented. Druggability parameters, different docking approaches and neutralization tendency of the natural products were employed in this study to screen the best possible natural compounds from the digital libraries. CONCLUSION: The results of this study conclude that compounds PALA and HMCA are potential inhibitors of SARS-CoV-2 spike protein and can be further explored for experimental validation. Overall, the methodological approach reported in this article can be suitably used to find the potential drug candidates against SARS-CoV2 in the burning situation of COVID-19 with less expenditure and a concise span of time.


Subject(s)
Antiviral Agents , COVID-19 , Antiviral Agents/pharmacology , Humans , Molecular Docking Simulation , SARS-CoV-2 , Spike Glycoprotein, Coronavirus
4.
J Infect Dev Ctries ; 14(12): 1368-1373, 2020 12 31.
Article in English | MEDLINE | ID: covidwho-1000365

ABSTRACT

INTRODUCTION: Current pandemic of the coronavirus induced disease 2019 (COVID-19) presents an urgent issue to the world due to lack of vaccine and medication. Hydroxychloroquine (HCQ) has generated a lot of controversies whether it is effective in prevention and treatment of COVID-19. Current report presents a 63-year-old woman who has taken HCQ for many years but still infected by COVID-19. CASE PRESENTATION: A patient with rheumatoid arthritis came to the clinic with fever and sore throat. The patient has been treated with 200 mg HCQ per day since 2016. Laboratory tests showed that the patient had lymphopenia, increased levels of high-sensitive C-reactive protein (hs-CRP) and serum Interleukin-6 (IL-6). Chest radiography showed that the patient had pneumonia. Throat swab test confirmed COVID-19 positive. On admission, she was treated with nebulized interferon alfa-2b, oral Lopinavir/Ritonavir, and ceftriaxone sodium for the COVID-19 in addition to HCQ. The patient stayed in hospital for 18 days, recovered from oxygen intake, and eventually discharged from hospital. Follow up investigation showed the patient developed antibody against COVID-19. CONCLUSIONS: Long-term application of HCQ could not prevent COVID-19 infection, but whether HCQ exerts benefit to alleviation of clinical symptoms and duration of hospital stays remains to be further investigated.


Subject(s)
Antiviral Agents/administration & dosage , COVID-19/prevention & control , Hydroxychloroquine/administration & dosage , Antiviral Agents/therapeutic use , COVID-19/diagnostic imaging , Female , Humans , Interferon alpha-2/therapeutic use , Middle Aged , Radiography , SARS-CoV-2/drug effects , Time Factors , Treatment Outcome
5.
Wellcome Open Res ; 5: 141, 2020.
Article in English | MEDLINE | ID: covidwho-895726

ABSTRACT

Background: COVID-19 is a respiratory disease caused by a novel coronavirus (SARS-CoV-2) and causes substantial morbidity and mortality. There is currently no vaccine to prevent COVID-19 or therapeutic agent to treat COVID-19. This clinical trial is designed to evaluate chloroquine as a potential therapeutic for the treatment of hospitalised people with COVID-19. We hypothesise that chloroquine slows viral replication in patients with COVID-19, attenuating the infection, and resulting in more rapid decline of viral load in throat/nose swabs. This viral attenuation should be associated with improved patient outcomes. Method: The study will start with a 10-patient prospective observational pilot study following the same entry and exclusion criteria as for the randomized trial and undergoing the same procedures. The main study is an open label, randomised, controlled trial with two parallel arms of standard of care (control arm) versus standard of care with 10 days of chloroquine (intervention arm) with a loading dose over the first 24 hours, followed by 300mg base orally once daily for nine days. The study will recruit patients in three sites in Ho Chi Minh City, Vietnam: the Hospital for Tropical Diseases, the Cu Chi Field Hospital, and the Can Gio COVID hospital. The primary endpoint is the time to viral clearance from throat/nose swab, defined as the time following randomization until the midpoint between the last positive and the first of the negative throat/nose swabs. Viral presence will be determined using RT-PCR to detect SARS-CoV-2 RNA. Discussion: The results of the study will add to the evidence-based guidelines for management of COVID-19. Given the enormous experience of its use in malaria chemoprophylaxis, excellent safety and tolerability profile, and its very low cost, if proved effective then chloroquine would be a readily deployable and affordable treatment for patients with COVID-19. Trial registration: Clinicaltrials.gov NCT04328493 31/03/2020.

6.
EMBO J ; 39(21): e106057, 2020 11 02.
Article in English | MEDLINE | ID: covidwho-846583

ABSTRACT

Coronavirus disease 2019 (COVID-19) is caused by SARS-CoV-2 and has spread across the globe. SARS-CoV-2 is a highly infectious virus with no vaccine or antiviral therapy available to control the pandemic; therefore, it is crucial to understand the mechanisms of viral pathogenesis and the host immune responses to SARS-CoV-2. SARS-CoV-2 is a new member of the betacoronavirus genus like other closely related viruses including SARS-CoV and Middle East respiratory syndrome coronavirus (MERS-CoV). Both SARS-CoV and MERS-CoV have caused serious outbreaks and epidemics in the past eighteen years. Here, we report that one of the interferon-stimulated genes (ISGs), cholesterol 25-hydroxylase (CH25H), is induced by SARS-CoV-2 infection in vitro and in COVID-19-infected patients. CH25H converts cholesterol to 25-hydrocholesterol (25HC) and 25HC shows broad anti-coronavirus activity by blocking membrane fusion. Furthermore, 25HC inhibits USA-WA1/2020 SARS-CoV-2 infection in lung epithelial cells and viral entry in human lung organoids. Mechanistically, 25HC inhibits viral membrane fusion by activating the ER-localized acyl-CoA:cholesterol acyltransferase (ACAT) which leads to the depletion of accessible cholesterol from the plasma membrane. Altogether, our results shed light on a potentially broad antiviral mechanism by 25HC through depleting accessible cholesterol on the plasma membrane to suppress virus-cell fusion. Since 25HC is a natural product with no known toxicity at effective concentrations, it provides a potential therapeutic candidate for COVID-19 and emerging viral diseases in the future.


Subject(s)
Antiviral Agents/pharmacology , Betacoronavirus/drug effects , Cholesterol/metabolism , Coronavirus Infections/drug therapy , Pneumonia, Viral/drug therapy , Respiratory Mucosa/virology , Steroid Hydroxylases/pharmacology , Virus Internalization/drug effects , Acetyl-CoA C-Acetyltransferase/metabolism , Animals , COVID-19 , Cell Line , Cell Membrane/drug effects , Cell Membrane/metabolism , Chlorocebus aethiops , Enzyme Activation/drug effects , Humans , Middle East Respiratory Syndrome Coronavirus/drug effects , Organoids/virology , Pandemics , Respiratory Mucosa/drug effects , SARS-CoV-2 , Vero Cells
7.
Curr Pharm Des ; 27(6): 866-875, 2021.
Article in English | MEDLINE | ID: covidwho-810094

ABSTRACT

BACKGROUND: COVID-19 pandemic is caused by coronavirus also known as severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). The viral infection continues to impact the globe with no vaccine to prevent the infection or highly effective therapeutics to treat the millions of infected people around the world. The disease starts as a respiratory infection, yet it may also be associated with a hypercoagulable state, severe inflammation owing to excessive cytokines production, and a potentially significant oxidative stress. The disease may progress to multiorgan failure and eventually death. OBJECTIVE: In this article, we summarize the potential of dipyridamole as an adjunct therapy for COVID-19. METHODS: We reviewed the literature describing the biological activities of dipyridamole in various settings of testing. Data were retrieved from PubMed, SciFinder-CAS, and Web of Science. The review concisely covered relevant studies starting from 1977. RESULTS: Dipyridamole is an approved antiplatelet drug, that has been used to prevent stroke, among other indications. Besides its antithrombotic activity, the literature indicates that dipyridamole also promotes a host of other biological activities including antiviral, anti-inflammatory, and antioxidant ones. CONCLUSION: Dipyridamole may substantially help improve the clinical outcomes of COVID-19 treatment. The pharmacokinetics profile of the drug is well established which makes it easier to design an appropriate therapeutic course. The drug is also generally safe, affordable, and available worldwide. Initial clinical trials have shown a substantial promise for dipyridamole in treating critically ill COVID-19 patients, yet larger randomized and controlled trials are needed to confirm this promise.


Subject(s)
COVID-19 , Pandemics , Antiviral Agents/therapeutic use , COVID-19/drug therapy , Dipyridamole , Humans , SARS-CoV-2
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