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1.
Perit Dial Int ; : 8968608221130559, 2022 Nov 01.
Article in English | MEDLINE | ID: covidwho-2245400

ABSTRACT

BACKGROUND: The high incidence of acute kidney injury (AKI) requiring dialysis associated with COVID-19 led to the use of peritoneal dialysis (PD) for the treatment of AKI. This study aims to compare in-hospital all-cause mortality and kidney recovery between patients with AKI who received acute PD versus extracorporeal dialysis (intermittent haemodialysis and continuous kidney replacement therapy). METHODS: In a retrospective observational study of 259 patients with AKI requiring dialysis during the COVID-19 surge during Spring 2020 in New York City, we compared 30-day all-cause mortality and kidney recovery between 93 patients who received acute PD at any time point and 166 patients who only received extracorporeal dialysis. Kaplan-Meier curves, log-rank test and Cox regression were used to compare survival and logistic regression was used to compare kidney recovery. RESULTS: The mean age was 61 ± 11 years; 31% were women; 96% had confirmed COVID-19 with median follow-up of 21 days. After adjusting for demographics, comorbidities, oxygenation and laboratory values prior to starting dialysis, the use of PD was associated with a lower mortality rate compared to extracorporeal dialysis with a hazard ratio of 0.48 (95% confidence interval: 0.27-0.82, p = 0.008). At discharge or on day 30 of hospitalisation, there was no association between dialysis modality and kidney recovery (p = 0.48). CONCLUSIONS: The use of PD for the treatment of AKI was not associated with worse clinical outcomes when compared to extracorporeal dialysis during the height of the COVID-19 pandemic in New York City. Given the inherent selection biases and residual confounding in our observational study, research with a larger cohort of patients in a more controlled setting is needed to confirm our findings.

2.
mBio ; 13(4): e0182222, 2022 08 30.
Article in English | MEDLINE | ID: covidwho-1962098

ABSTRACT

The U.S. Food and Drug Administration-authorized mRNA- and adenovirus-based SARS-CoV-2 vaccines are intramuscularly injected in two doses and effective in preventing COVID-19, but they do not induce efficient mucosal immunity or prevent viral transmission. Here, we report the first noninfectious, bacteriophage T4-based, multicomponent, needle- and adjuvant-free, mucosal vaccine harboring engineered Spike trimers on capsid exterior and nucleocapsid protein in the interior. Intranasal administration of two doses of this T4 SARS-CoV-2 vaccine 21 days apart induced robust mucosal immunity, in addition to strong systemic humoral and cellular immune responses. The intranasal vaccine induced broad virus neutralization antibody titers against multiple variants, Th1-biased cytokine responses, strong CD4+ and CD8+ T cell immunity, and high secretory IgA titers in sera and bronchoalveolar lavage specimens from vaccinated mice. All of these responses were much stronger in intranasally vaccinated mice than those induced by the injected vaccine. Furthermore, the nasal vaccine provided complete protection and sterilizing immunity against the mouse-adapted SARS-CoV-2 MA10 strain, the ancestral WA-1/2020 strain, and the most lethal Delta variant in both BALB/c and human angiotensin converting enzyme (hACE2) knock-in transgenic mouse models. In addition, the vaccine elicited virus-neutralizing antibodies against SARS-CoV-2 variants in bronchoalveolar lavage specimens, did not affect the gut microbiota, exhibited minimal lung lesions in vaccinated and challenged mice, and is completely stable at ambient temperature. This modular, needle-free, phage T4 mucosal vaccine delivery platform is therefore an excellent candidate for designing efficacious mucosal vaccines against other respiratory infections and for emergency preparedness against emerging epidemic and pandemic pathogens. IMPORTANCE According to the World Health Organization, COVID-19 may have caused ~15-million deaths across the globe and is still ravaging the world. Another wave of ~100 million infections is predicted in the United States due to the emergence of highly transmissible immune-escaped Omicron variants. The authorized vaccines would not prevent these transmissions since they do not trigger mucosal immunity. We circumvented this limitation by developing a needle-free, bacteriophage T4-based, mucosal vaccine. This intranasally administered vaccine generates superior mucosal immunity in mice, in addition to inducing robust humoral and cell-mediated immune responses, and provides complete protection and sterilizing immunity against SARS-CoV-2 variants. The vaccine is stable, adjuvant-free, and cost-effectively manufactured and distributed, making it a strategically important next-generation COVID vaccine for ending this pandemic.


Subject(s)
Bacteriophages , COVID-19 , Adjuvants, Immunologic , Animals , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/prevention & control , COVID-19 Vaccines , Humans , Mice , Mice, Inbred BALB C , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/genetics
3.
Nat Commun ; 13(1): 4284, 2022 07 25.
Article in English | MEDLINE | ID: covidwho-1956403

ABSTRACT

The SARS-CoV-2 frameshifting element (FSE), a highly conserved mRNA region required for correct translation of viral polyproteins, defines an excellent therapeutic target against Covid-19. As discovered by our prior graph-theory analysis with SHAPE experiments, the FSE adopts a heterogeneous, length-dependent conformational landscape consisting of an assumed 3-stem H-type pseudoknot (graph motif 3_6), and two alternative motifs (3_3 and 3_5). Here, for the first time, we build and simulate, by microsecond molecular dynamics, 30 models for all three motifs plus motif-stabilizing mutants at different lengths. Our 3_6 pseudoknot systems, which agree with experimental structures, reveal interconvertible L and linear conformations likely related to ribosomal pausing and frameshifting. The 3_6 mutant inhibits this transformation and could hamper frameshifting. Our 3_3 systems exhibit length-dependent stem interactions that point to a potential transition pathway connecting the three motifs during ribosomal elongation. Together, our observations provide new insights into frameshifting mechanisms and anti-viral strategies.


Subject(s)
COVID-19 , Frameshifting, Ribosomal , Base Sequence , Humans , Nucleic Acid Conformation , RNA, Viral/chemistry , RNA, Viral/genetics , SARS-CoV-2/genetics
4.
Asian J Neurosurg ; 16(4): 685-691, 2021.
Article in English | MEDLINE | ID: covidwho-1650177

ABSTRACT

INTRODUCTION: It has been 17 years since the severe acute respiratory syndrome outbreak and Singapore is facing yet another daunting pandemic - the novel coronavirus (COVID-19). To date, there are 57,607 cases and 27 casualties. This deadly pandemic requires significant changes especially in the field of awake surgeries for intra-axial tumors that routinely involve long clinic consults, significant interactions between patient and multiple other team members pre, intra, and postoperatively. MATERIALS AND METHODS: A retrospective review of all awake cases done during the COVID-19 pandemic from February to June 2020 was done. In this article, we outline the rigorous measures adopted during the COVID-19 pandemic that has allowed us to proceed with awake surgeries and intraoperative mapping at our institution. RESULTS AND DISCUSSION: We have divided the protocol into various phases of care of patients planned for an awake craniotomy. Preoperatively, teleconsults have been used where possible thereby limiting multiple hospital visits and interaction. Intraoperatively, safety nets have been established during asleep-awake-asleep phases of awake craniotomy for all the team members. Postoperatively, early discharge and teleconsult are being employed for rehabilitation and follow-ups. CONCLUSIONS: Multiple studies have shown that with intraoperative mapping, we can improve neurological outcomes. As the future of the pandemic remains unknown, the authors believe that surgical treatment should not be delayed for intracranial tumors. Awake craniotomies and intraoperative mapping can be safely carried out by adopting the described protocols with combination of multiple checkpoints and usage of telecommunication.

5.
Methods Mol Biol ; 2410: 209-228, 2022.
Article in English | MEDLINE | ID: covidwho-1576030

ABSTRACT

The COVID-19 pandemic brought to the fore the urgent need for vaccine design and delivery platforms that can be rapidly deployed for manufacture and distribution. Though the mRNA and adenoviral vector platforms have been enormously successful to control SARS-CoV-2 viral infections, it is unclear if this could be replicated against more complex pathogens or the emerging variants. Recently, we described a "universal" platform that can incorporate multiple vaccine targets into the same nanoparticle scaffold by CRISPR engineering of bacteriophage T4. A T4-COVID vaccine designed with this technology elicited broad immunogenicity and complete protection against virus challenge in a mouse model. Here, we describe the detailed methodology to generate recombinant bacteriophage T4 backbones using CRISPR that can also be broadly applicable to other bacteriophages that abundantly pervade the Earth.


Subject(s)
Bacteriophage T4 , COVID-19 Vaccines , COVID-19 , Clustered Regularly Interspaced Short Palindromic Repeats , Animals , Bacteriophage T4/genetics , COVID-19/prevention & control , Humans , Mice , Pandemics , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , Vaccine Development
6.
Sci Adv ; 7(37): eabh1547, 2021 Sep 10.
Article in English | MEDLINE | ID: covidwho-1405213

ABSTRACT

A "universal" platform that can rapidly generate multiplex vaccine candidates is critically needed to control pandemics. Using the severe acute respiratory syndrome coronavirus 2 as a model, we have developed such a platform by CRISPR engineering of bacteriophage T4. A pipeline of vaccine candidates was engineered by incorporating various viral components into appropriate compartments of phage nanoparticle structure. These include expressible spike genes in genome, spike and envelope epitopes as surface decorations, and nucleocapsid proteins in packaged core. Phage decorated with spike trimers was found to be the most potent vaccine candidate in animal models. Without any adjuvant, this vaccine stimulated robust immune responses, both T helper cell 1 (TH1) and TH2 immunoglobulin G subclasses, blocked virus-receptor interactions, neutralized viral infection, and conferred complete protection against viral challenge. This new nanovaccine design framework might allow the rapid deployment of effective adjuvant-free phage-based vaccines against any emerging pathogen in the future.

7.
J Am Chem Soc ; 143(30): 11404-11422, 2021 08 04.
Article in English | MEDLINE | ID: covidwho-1317796

ABSTRACT

The SARS-CoV-2 frameshifting RNA element (FSE) is an excellent target for therapeutic intervention against Covid-19. This small gene element employs a shifting mechanism to pause and backtrack the ribosome during translation between Open Reading Frames 1a and 1b, which code for viral polyproteins. Any interference with this process has a profound effect on viral replication and propagation. Pinpointing the structures adapted by the FSE and associated structural transformations involved in frameshifting has been a challenge. Using our graph-theory-based modeling tools for representing RNA secondary structures, "RAG" (RNA-As-Graphs), and chemical structure probing experiments, we show that the 3-stem H-type pseudoknot (3_6 dual graph), long assumed to be the dominant structure, has a viable alternative, an HL-type 3-stem pseudoknot (3_3) for longer constructs. In addition, an unknotted 3-way junction RNA (3_5) emerges as a minor conformation. These three conformations share Stems 1 and 3, while the different Stem 2 may be involved in a conformational switch and possibly associations with the ribosome during translation. For full-length genomes, a stem-loop motif (2_2) may compete with these forms. These structural and mechanistic insights advance our understanding of the SARS-CoV-2 frameshifting process and concomitant virus life cycle, and point to three avenues of therapeutic intervention.


Subject(s)
RNA, Viral/chemistry , SARS-CoV-2/chemistry , Base Sequence , Inverted Repeat Sequences , Models, Molecular , Nucleic Acid Conformation , RNA, Viral/genetics
8.
Biophys J ; 120(6): 1040-1053, 2021 03 16.
Article in English | MEDLINE | ID: covidwho-1083814

ABSTRACT

With the rapid rate of COVID-19 infections and deaths, treatments and cures besides hand washing, social distancing, masks, isolation, and quarantines are urgently needed. The treatments and vaccines rely on the basic biophysics of the complex viral apparatus. Although proteins are serving as main drug and vaccine targets, therapeutic approaches targeting the 30,000 nucleotide RNA viral genome form important complementary approaches. Indeed, the high conservation of the viral genome, its close evolutionary relationship to other viruses, and the rise of gene editing and RNA-based vaccines all argue for a focus on the RNA agent itself. One of the key steps in the viral replication cycle inside host cells is the ribosomal frameshifting required for translation of overlapping open reading frames. The RNA frameshifting element (FSE), one of three highly conserved regions of coronaviruses, is believed to include a pseudoknot considered essential for this ribosomal switching. In this work, we apply our graph-theory-based framework for representing RNA secondary structures, "RAG (or RNA-As-Graphs)," to alter key structural features of the FSE of the SARS-CoV-2 virus. Specifically, using RAG machinery of genetic algorithms for inverse folding adapted for RNA structures with pseudoknots, we computationally predict minimal mutations that destroy a structurally important stem and/or the pseudoknot of the FSE, potentially dismantling the virus against translation of the polyproteins. Our microsecond molecular dynamics simulations of mutant structures indicate relatively stable secondary structures. These findings not only advance our computational design of RNAs containing pseudoknots, they pinpoint key residues of the SARS-CoV-2 virus as targets for antiviral drugs and gene editing approaches.


Subject(s)
Frameshifting, Ribosomal/genetics , Mutation/genetics , RNA, Viral/chemistry , RNA, Viral/genetics , SARS-CoV-2/chemistry , SARS-CoV-2/genetics , Algorithms , Gene Editing , Molecular Dynamics Simulation , Nucleic Acid Conformation
9.
Vaccines (Basel) ; 8(4)2020 Nov 03.
Article in English | MEDLINE | ID: covidwho-967246

ABSTRACT

With a death toll of over one million worldwide, the COVID-19 pandemic caused by SARS-CoV-2 has become the most devastating humanitarian catastrophe in recent decades. The fear of acquiring infection and spreading to vulnerable people has severely impacted society's socio-economic status. To put an end to this growing number of infections and deaths as well as to switch from restricted to everyday living, an effective vaccine is desperately needed. As a result, enormous efforts have been made globally to develop numerous vaccine candidates in a matter of months. Currently, over 30 vaccine candidates are under assessment in clinical trials, with several undergoing preclinical studies. Here, we reviewed the major vaccine candidates based on the specific vaccine platform utilized to develop them. We also discussed the immune responses generated by these candidates in humans and preclinical models to determine vaccine safety, immunogenicity, and efficacy. Finally, immune responses induced in recovered COVID-19 patients and their possible vaccine development implications were also briefly reviewed.

10.
Vaccines ; 8(4):649, 2020.
Article in English | MDPI | ID: covidwho-896368

ABSTRACT

With a death toll of over one million worldwide, the COVID-19 pandemic caused by SARS-CoV-2 has become the most devastating humanitarian catastrophe in recent decades. The fear of acquiring infection and spreading to vulnerable people has severely impacted society’s socio-economic status. To put an end to this growing number of infections and deaths as well as to switch from restricted to everyday living, an effective vaccine is desperately needed. As a result, enormous efforts have been made globally to develop numerous vaccine candidates in a matter of months. Currently, over 30 vaccine candidates are under assessment in clinical trials, with several undergoing preclinical studies. Here, we reviewed the major vaccine candidates based on the specific vaccine platform utilized to develop them. We also discussed the immune responses generated by these candidates in humans and preclinical models to determine vaccine safety, immunogenicity, and efficacy. Finally, immune responses induced in recovered COVID-19 patients and their possible vaccine development implications were also briefly reviewed.

11.
Tob Use Insights ; 13: 1179173X20960447, 2020.
Article in English | MEDLINE | ID: covidwho-841277

ABSTRACT

Entire world is battling the Novel Coronavirus Disease (COVID-19) pandemic. India too, has undertaken stringent containment measures to combat this disease. The country is in a state of national lockdown, which has inadvertently led more than a quarter of the Indian population to not use tobacco. This paper discusses the opportunity that surfaces with unavailability of tobacco products, and advocates the need for escalation of tobacco cessation services as well as strategic management of stress to stay tobacco-free.

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