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1.
Materials Letters ; 318:132238, 2022.
Article in English | ScienceDirect | ID: covidwho-1778362

ABSTRACT

Used face masks resulting from the COVID-19 pandemic are forming a new waste stream that poses a considerable environmental risk to the ecosystem if not properly disposed of. This work explored an environmentally friendly solution to diverting such waste to a value-added application, i.e., fabricating waste mask microfibers for use in cementitious composites. To improve the interfacial transition zone between mask fibers and cement paste matrix, the microfibers made from recycled medical masks are pre-treated in an aqueous solution of graphene oxide (GO, at 0.05 wt%). In a cement paste with the water/cement ratio of 0.40, the GO-treated mask fibers admixed at 0.1 vol% showed great potential for improving the splitting tensile strength (by 47% at 28 days), even though they slightly decreased the compressive strength of the paste (by 3% at 28 days). Microscopic investigation was also carried out to reveal the enhancement mechanism of GO-treated fibers. This study preliminarily demonstrated the feasibility to upcycle waste masks in the concrete industry and provided a new strategy for disposing of waste masks.

2.
J Genet Genomics ; 48(9): 803-814, 2021 09 20.
Article in English | MEDLINE | ID: covidwho-1720312

ABSTRACT

Children are less susceptible to coronavirus disease 2019 (COVID-19), and they have manifested lower morbidity and mortality after infection, for which a multitude of mechanisms may be considered. Whether the normal development of the gut-airway microbiome in children is affected by COVID-19 has not been evaluated. Here, we demonstrate that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection alters the upper respiratory tract and the gut microbiomes in nine children. The alteration of the microbiome is dominated by the genus Pseudomonas, and it sustains for up to 25-58 days in different individuals. Moreover, the patterns of alternation are different between the upper respiratory tract and the gut. Longitudinal investigation shows that the upper respiratory tract and the gut microbiomes are extremely variable among children during the course of COVID-19. The dysbiosis of microbiome persists in 7 of 8 children for at least 19-24 days after discharge from the hospital. Disturbed development of both the gut and the upper respiratory microbiomes and prolonged dysbiosis in these nine children imply possible long-term complications after clinical recovery from COVID-19, such as predisposition to the increased health risk in the post-COVID-19 era.


Subject(s)
COVID-19/pathology , Computational Biology/methods , Respiratory Tract Infections/microbiology , Dysbiosis/microbiology , Dysbiosis/pathology , Gastrointestinal Microbiome/physiology , Humans
3.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-325281

ABSTRACT

COVID-19 patients worldwide are conveniently described by position information to collect samples, and modern GIS maps are useful to show influenced flows and numbers of patients on various regions of a pendamic. From an analysis viewpoint, it is more interesting to organize genomic information into a phylogenic tree with multiple branches and leaves in representations. Clusters of genomes are organized as phylogenic trees to represent intrinsic information of genomes. However, there are structural difficulties in projecting phylogenetic information into 2D distributions as GIS maps naturally.Considering advanced generating schemes of phylogenetic trees, information entropy provides ultra optimal properties in the minimum computational complexity, superior flexibility, better stability, improved reliability and higher quality on global constructions.In this paper, a novel projection is proposed to arrange SARS-CoV-2 genomes by genomic indexes to make a structural organization as 2D GIS maps. For any genome, there is a unique invariant under certain conditions to provide an absolute position on a specific region. In this hierarchical framework, it is possible to use a visual tool to represent any selected region for clustering genomes on refined effects. Applied diversity measure to a given set of genomes, equivalent clusters and complementary visual effects are provided between genomic index maps and phylogenetic trees. Sample genomes of three UK new lineages are aligned by BLAST as a basis on both RNA-dependent RNA polymerase RDRP segments and whole genomes. Selected regions and various projections show spread effects of five thousand SARS-CoV-2 genomes in 72 countries on both RDRP and whole genomes, and six special countries/regions are selected on genomic index maps.Based on genomic index maps, one SNV of two genomes on B.1.1.7 lineage can be identified from a unit of 10

4.
Zool Res ; 42(6): 834-844, 2021 11 18.
Article in English | MEDLINE | ID: covidwho-1515719

ABSTRACT

Understanding the zoonotic origin and evolution history of SARS-CoV-2 will provide critical insights for alerting and preventing future outbreaks. A significant gap remains for the possible role of pangolins as a reservoir of SARS-CoV-2 related coronaviruses (SC2r-CoVs). Here, we screened SC2r-CoVs in 172 samples from 163 pangolin individuals of four species, and detected positive signals in muscles of four Manis javanica and, for the first time, one M. pentadactyla. Phylogeographic analysis of pangolin mitochondrial DNA traced their origins from Southeast Asia. Using in-solution hybridization capture sequencing, we assembled a partial pangolin SC2r-CoV (pangolin-CoV) genome sequence of 22 895 bp (MP20) from the M. pentadactyla sample. Phylogenetic analyses revealed MP20 was very closely related to pangolin-CoVs that were identified in M. javanica seized by Guangxi Customs. A genetic contribution of bat coronavirus to pangolin-CoVs via recombination was indicated. Our analysis revealed that the genetic diversity of pangolin-CoVs is substantially higher than previously anticipated. Given the potential infectivity of pangolin-CoVs, the high genetic diversity of pangolin-CoVs alerts the ecological risk of zoonotic evolution and transmission of pathogenic SC2r-CoVs.


Subject(s)
COVID-19/veterinary , Evolution, Molecular , Pangolins/virology , SARS-CoV-2/genetics , Animals , Genome, Viral , Phylogeny , RNA, Viral/genetics
5.
Front Microbiol ; 12: 649314, 2021.
Article in English | MEDLINE | ID: covidwho-1485070

ABSTRACT

Knowledge about coronaviruses (CoVs) with furin cleavage sites is extremely limited, although these sites mediate the hydrolysis of glycoproteins in plasma membranes required for MERS-CoV or SARS-CoV-2 to enter cells and infect humans. Thus, we have examined the global epidemiology and evolutionary history of SARS-CoV-2 and 248 other CoVs with 86 diversified furin cleavage sites that have been detected in 24 animal hosts in 28 countries since 1954. Besides MERS-CoV and SARS-CoV-2, two of five other CoVs known to infect humans (HCoV-OC43 and HCoV-HKU1) also have furin cleavage sites. In addition, human enteric coronavirus (HECV-4408) has a furin cleavage site and has been detected in humans (first in Germany in 1988), probably via spillover events from bovine sources. In conclusion, the presence of furin cleavage sites might explain the polytropic nature of SARS-CoV-2- and SARS-CoV-2-like CoVs, which would be helpful for ending the COVID-19 pandemic and preventing outbreaks of novel CoVs.

6.
Sci Transl Med ; 13(606)2021 08 11.
Article in English | MEDLINE | ID: covidwho-1319371

ABSTRACT

Multiple safe and effective vaccines that elicit immune responses against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are necessary to respond to the ongoing coronavirus disease 2019 (COVID-19) pandemic. Here, we developed a protein subunit vaccine composed of spike ectodomain protein (StriFK) plus a nitrogen bisphosphonate-modified zinc-aluminum hybrid adjuvant (FH002C). StriFK-FH002C generated substantially higher neutralizing antibody titers in mice, hamsters, and cynomolgus monkeys than those observed in plasma isolated from COVID-19 convalescent individuals. StriFK-FH002C also induced both TH1- and TH2-polarized helper T cell responses in mice. In hamsters, StriFK-FH002C immunization protected animals against SARS-CoV-2 challenge, as shown by the absence of virus-induced weight loss, fewer symptoms of disease, and reduced lung pathology. Vaccination of hamsters with StriFK-FH002C also reduced within-cage virus transmission to unvaccinated, cohoused hamsters. In summary, StriFK-FH002C represents an effective, protein subunit-based SARS-CoV-2 vaccine candidate.


Subject(s)
COVID-19 , Animals , Antibodies, Neutralizing , Antibodies, Viral , COVID-19 Vaccines , Cricetinae , Humans , Mice , Protein Subunits , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/genetics
7.
Expert Rev Vaccines ; 20(7): 797-810, 2021 07.
Article in English | MEDLINE | ID: covidwho-1260998

ABSTRACT

Introduction: Adjuvants are essential to vaccines for immunopotentiation in the elicitation of protective immunity. However, classical and widely used aluminum-based adjuvants have limited capacity to induce cellular response. There are increasing needs for appropriate adjuvants with improved profiles for vaccine development toward emerging pathogens. Carbohydrate-containing nanoparticles (NPs) with immunomodulatory activity and particulate nanocarriers for effective antigen presentation are capable of eliciting a more balanced humoral and cellular immune response.Areas covered: We reviewed several carbohydrates with immunomodulatory properties. They include chitosan, ß-glucan, mannan, and saponins, which have been used in vaccine formulations. The mode of action, the preparation methods, characterization of these carbohydrate-containing NPs and the corresponding vaccines are presented.Expert opinion: Several carbohydrate-containing NPs have entered the clinical stage or have been used in licensed vaccines for human use. Saponin-containing NPs are being evaluated in a vaccine against SARS-CoV-2, the pathogen causing the on-going worldwide pandemic. Vaccines with carbohydrate-containing NPs are in different stages of development, from preclinical studies to late-stage clinical trials. A better understanding of the mode of action for carbohydrate-containing NPs as vaccine carriers and as immunostimulators will likely contribute to the design and development of new generation vaccines against cancer and infectious diseases.


Subject(s)
Adjuvants, Immunologic/chemistry , COVID-19 Vaccines/chemistry , COVID-19/prevention & control , Carbohydrates/chemistry , Nanoparticles/chemistry , Adjuvants, Immunologic/administration & dosage , Animals , COVID-19/immunology , COVID-19 Vaccines/administration & dosage , COVID-19 Vaccines/immunology , Carbohydrates/administration & dosage , Carbohydrates/immunology , Chitosan/administration & dosage , Chitosan/chemistry , Chitosan/immunology , Humans , Mannans/administration & dosage , Mannans/chemistry , Mannans/immunology , Nanoparticles/administration & dosage , beta-Glucans/administration & dosage , beta-Glucans/chemistry , beta-Glucans/immunology
8.
Commun Biol ; 4(1): 240, 2021 02 18.
Article in English | MEDLINE | ID: covidwho-1091448

ABSTRACT

SARS-CoV-2 is the cause of COVID-19. It infects multiple organs including the respiratory tract and gut. Dynamic changes of regional microbiomes in infected adults are largely unknown. Here, we performed longitudinal analyses of throat and anal swabs from 35 COVID-19 and 19 healthy adult controls, as well as 10 non-COVID-19 patients with other diseases, by 16 S rRNA gene sequencing. The results showed a partitioning of the patients into 3-4 categories based on microbial community types (I-IV) in both sites. The bacterial diversity was lower in COVID-19 patients than healthy controls and decreased gradually from community type I to III/IV. Although the dynamic change of microbiome was complex during COVID-19, a synchronous restoration of both the upper respiratory and gut microbiomes from early dysbiosis towards late more diverse status was observed in 6/8 mild COVID-19 adult patients. These findings reveal previously unknown interactions between upper respiratory and gut microbiomes during COVID-19.


Subject(s)
COVID-19/microbiology , Gastrointestinal Microbiome , Microbiota , Respiratory System/microbiology , SARS-CoV-2 , Adolescent , Adult , Aged , Female , Gastrointestinal Microbiome/genetics , Humans , Male , Microbiota/genetics , Middle Aged , RNA, Ribosomal, 16S/genetics , Young Adult
9.
Curr Biol ; 30(8): 1578, 2020 04 20.
Article in English | MEDLINE | ID: covidwho-833445
10.
SSRN; 2020.
Preprint | SSRN | ID: ppcovidwho-549

ABSTRACT

In the late December of 2019, an epidemic pneumonia (announced recently as Corona Virus Disease (COVID-19)) outbreak in city of Wuhan in China and widely spread

11.
Zool Res ; 41(3): 213-219, 2020 May 18.
Article in English | MEDLINE | ID: covidwho-210902

ABSTRACT

The ongoing pandemic of coronavirus disease 2019 (COVID-19), caused by infection with human coronavirus 2019 (HCoV-19 / SARS-CoV-2 / 2019-nCoV), is a global threat to the human population. Here, we briefly summarize the available data for the zoonotic origins of HCoV-19, with reference to the other two epidemics of highly virulent coronaviruses, SARS-CoV and MERS-CoV, which cause severe pneumonia in humans. We propose to intensify future efforts for tracing the origins of HCoV-19, which is a very important scientific question for the control and prevention of the pandemic.


Subject(s)
Betacoronavirus/physiology , Coronavirus Infections/transmission , Pneumonia, Viral/transmission , Zoonoses , Animals , COVID-19 , Coronavirus Infections/virology , Disease Reservoirs , Humans , Pandemics , Pneumonia, Viral/virology , SARS-CoV-2
12.
Curr Biol ; 30(7): 1346-1351.e2, 2020 04 06.
Article in English | MEDLINE | ID: covidwho-10553

ABSTRACT

An outbreak of coronavirus disease 2019 (COVID-19) caused by the 2019 novel coronavirus (SARS-CoV-2) began in the city of Wuhan in China and has widely spread worldwide. Currently, it is vital to explore potential intermediate hosts of SARS-CoV-2 to control COVID-19 spread. Therefore, we reinvestigated published data from pangolin lung samples from which SARS-CoV-like CoVs were detected by Liu et al. [1]. We found genomic and evolutionary evidence of the occurrence of a SARS-CoV-2-like CoV (named Pangolin-CoV) in dead Malayan pangolins. Pangolin-CoV is 91.02% and 90.55% identical to SARS-CoV-2 and BatCoV RaTG13, respectively, at the whole-genome level. Aside from RaTG13, Pangolin-CoV is the most closely related CoV to SARS-CoV-2. The S1 protein of Pangolin-CoV is much more closely related to SARS-CoV-2 than to RaTG13. Five key amino acid residues involved in the interaction with human ACE2 are completely consistent between Pangolin-CoV and SARS-CoV-2, but four amino acid mutations are present in RaTG13. Both Pangolin-CoV and RaTG13 lost the putative furin recognition sequence motif at S1/S2 cleavage site that can be observed in the SARS-CoV-2. Conclusively, this study suggests that pangolin species are a natural reservoir of SARS-CoV-2-like CoVs.


Subject(s)
Betacoronavirus/genetics , Betacoronavirus/isolation & purification , Coronavirus Infections/virology , Disease Reservoirs/virology , Eutheria/virology , Pneumonia, Viral/virology , Amino Acid Sequence , Animals , COVID-19 , Chiroptera , Genome, Viral , Malaysia , Pandemics , Phylogeny , SARS-CoV-2 , Sequence Alignment , Spike Glycoprotein, Coronavirus/chemistry
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