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1.
Sci Total Environ ; : 159435, 2022 Oct 13.
Article in English | MEDLINE | ID: covidwho-2069673

ABSTRACT

Anthropogenic emissions reduced sharply in the short-term during the coronavirus disease pandemic (COVID-19). As COVID-19 is still ongoing, changes in atmospheric aerosol loading over China and the factors of their variations remain unclear. In this study, we used multi-source satellite observations and reanalysis datasets to synergistically analyze the spring (February-May) evolution of aerosol optical depth (AOD) for multiple aerosol types over Eastern China (EC) before, during and after the COVID-19 lockdown period. Regional meteorological effects and the radiative response were also quantitatively assessed. Compared to the same period before COVID-19 (i.e., in 2019), a total decrease of -14.6 % in tropospheric TROPOMI nitrogen dioxide (NO2) and a decrease of -6.8 % in MODIS AOD were observed over EC during the lockdown period (i.e., in 2020). After the lockdown period (i.e., in 2021), anthropogenic emissions returned to previous levels and there was a slight increase (+2.3 %) in AOD over EC. Moreover, changes in aerosol loading have spatial differences. AOD decreased significantly in the North China Plain (-14.0 %, NCP) and Yangtze River Delta (-9.4 %) regions, where anthropogenic aerosol dominated the aerosol loading. Impacted by strong wildfires in Southeast Asia during the lockdown period, carbonaceous AOD increased by +9.1 % in South China, which partially offset the emission reductions. Extreme dust storms swept through the northern region in the period after COVID-19, with an increase of +23.5 % in NCP and + 42.9 % in Northeast China (NEC) for dust AOD. However, unfavorable meteorological conditions overwhelmed the benefits of emission reductions, resulting in a +20.1 % increase in AOD in NEC during the lockdown period. Furthermore, the downward shortwave radiative flux showed a positive anomaly due to the reduced aerosol loading in the atmosphere during the lockdown period. This study highlights that we can benefit from short-term controls for the improvement of air pollution, but we also need to seriously considered the cross-regional transport of natural aerosol and meteorological drivers.

2.
Molecules ; 27(19)2022 Sep 23.
Article in English | MEDLINE | ID: covidwho-2066272

ABSTRACT

Streptococcus pneumoniae (S. pneumoniae), as a Gram-positive bacterium, can cause severe bacterial pneumonia, and result in high morbidity and mortality in infected people. Meanwhile, isolated drug-resistant S. pneumoniae is growing, which raises concerns about strategies for combatting S. pneumoniae infection. To disturb S. pneumoniae pathogenicity and its drug-resistance, developing novel anti-infective strategies or compounds is urgent. In this study, the anti-infective effect of shionone was explored. A minimum inhibitory concentration (MIC) assay and growth curve determination were performed to evaluate the effect of the tetracyclic triterpenoid compound shionone against S. pneumoniae. Hemolysis tests, western blotting, oligomerization inhibition assays, and molecular docking were carried out to explore the anti-infective mechanism of shionone. Moreover, the protective effect of shionone was also confirmed in a mousepneumonia model. The results showed that the excellent hemolytic inhibitory activity of shionone was observed at less than 8 µg/mL. Meanwhile, shionone could disturb the oligomerization of pneumolysin (PLY) but did not interfere with PLY expression at less than 4 µg/mL. Molecular docking suggested that shionone targeted the ASP-59, ILE-60, THR-57, PHE-344, and ASN-346 amino acid sites to reduce S. pneumoniae pathogenicity. Furthermore, shionone alleviated lung histopathologic injury and decreased lung bacterial colonization in vivo. The above results showed that shionone could bind to the PLY active pocket under the concentrations of 8 µg/mL and neutralize PLY hemolysis activity to reduce S. pneumoniae pathogenicity in vitro and in vivo.


Subject(s)
Acute Lung Injury , Triterpenes , Amino Acids/pharmacology , Bacterial Proteins/metabolism , Hemolysis , Humans , Molecular Docking Simulation , Streptococcus pneumoniae , Streptolysins/metabolism , Streptolysins/pharmacology , Triterpenes/pharmacology
3.
Cell Rep ; 41(5): 111528, 2022 Nov 01.
Article in English | MEDLINE | ID: covidwho-2060517

ABSTRACT

The emergence and global spread of the SARS-CoV-2 Omicron variants, which carry an unprecedented number of mutations, raise serious concerns due to the reduced efficacy of current vaccines and resistance to therapeutic antibodies. Here, we report the generation and characterization of two potent human monoclonal antibodies, NA8 and NE12, against the receptor-binding domain of the SARS-CoV-2 spike protein. NA8 interacts with a highly conserved region and has a breadth of neutralization with picomolar potency against the Beta variant and the Omicron BA.1 and BA.2 sublineages and nanomolar potency against BA.2.12.1 and BA.4. Combination of NA8 and NE12 retains potent neutralizing activity against the major SARS-CoV-2 variants of concern. Cryo-EM analysis provides the structural basis for the broad and complementary neutralizing activity of these two antibodies. We confirm the in vivo protective and therapeutic efficacies of NA8 and NE12 in the hamster model. These results show that broad and potent human antibodies can overcome the continuous immune escape of evolving SARS-CoV-2 variants.


Subject(s)
Antineoplastic Agents, Immunological , COVID-19 , Humans , SARS-CoV-2 , Antibodies, Monoclonal/pharmacology , Antibodies, Monoclonal/therapeutic use , Antibodies, Monoclonal/genetics , Neutralization Tests , Antibodies, Viral/therapeutic use , Viral Envelope Proteins , Membrane Glycoproteins/genetics , Antibodies, Neutralizing/therapeutic use
4.
Frontiers in molecular biosciences ; 9, 2022.
Article in English | EuropePMC | ID: covidwho-2058256

ABSTRACT

We calculate the thermal and conformational states of the spike glycoprotein (S-protein) of SARS-CoV-2 at seven temperatures ranging from 3°C to 95°C by all-atom molecular dynamics (MD) µs-scale simulations with the objectives to understand the structural variations on the temperatures and to determine the potential phase transition while trying to correlate such findings of the S-protein with the observed properties of the SARS-CoV2. Our simulations revealed the following thermal properties of the S-protein: 1) It is structurally stable at 3°C, agreeing with observations that the virus stays active for more than two weeks in the cold supply chain;2) Its structure varies more significantly at temperature values of 60°C–80°C;3) The sharpest structural variations occur near 60°C, signaling a plausible critical temperature nearby;4) The maximum deviation of the receptor-binding domain at 37°C, corroborating the anecdotal observations that the virus is most infective at 37°C;5) The in silico data agree with reported experiments of the SARS-CoV-2 survival times from weeks to seconds by our clustering approach analysis. Our MD simulations at µs scales demonstrated the S-protein’s thermodynamics of the critical states at around 60°C, and the stable and denatured states for temperatures below and above this value, respectively.

5.
TrAC Trends in Analytical Chemistry ; : 116767, 2022.
Article in English | ScienceDirect | ID: covidwho-2031715

ABSTRACT

Aptamers are single-stranded DNA or RNA oligonucleotides that can selectively bind to a specific target. They are generally obtained by SELEX, but the procedure is challenging and time-consuming. Moreover, the identified aptamers tend to be insufficient in stability, specificity, and affinity. Thus, only a handful of aptamers have entered the practical use stage. Recently, computational approaches have demonstrated a significant capacity to assist in the discovery of high-performance aptamers. This review discusses the advances achieved in several aspects of computational tools in this field, as well as the new progress in machine learning and deep learning, which are used in aptamer identification and optimization. To illustrate these computationally aided processes, aptamers selection against SARS-CoV-2 is discussed in detail as a case study. We hope that this review will aid and motivate researchers to develop and utilize more computational techniques to discover ideal aptamers effectively.

6.
Food Control ; : 109340, 2022.
Article in English | ScienceDirect | ID: covidwho-2007702

ABSTRACT

The detection of infectious SARS-CoV-2 in food and food packaging associated with the cold chain has raised concerns about the possible transmission pathway of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in foods transported through cold-chain logistics and the need for novel decontamination strategies. In this study, the effect of electron beam (E-beam) irradiation on the inactivation of two SARS-CoV-2surrogate, viruses porcine epidemic diarrhea virus (PEDV) and porcine transmissible gastroenteritis virus (TGEV), in culture medium and food substrate, and on food substrate were investigated. The causes of virus inactivation were also investigated by transmission electron microscopy (TEM) and Quantitative Real-time PCR (QRT-PCR). Samples packed inside and outside, including virus-inoculated large yellow croaker and virus suspensions, were irradiated with E-beam irradiation (2, 4, 6, 8, 10 kGy) under refrigerated (0 °C)and frozen (−18 °C) conditions. The titers of both viruses in suspension and fish decreased significantly (P < 0.05) with increasing doses of E-beam irradiation. The maximum D10 value of both viruses in suspension and fish was 1.24 kGy. E-beam irradiation at doses below 10 kGy was found to destroy the spike proteins of both SARS-CoV-2 surrogate viruses by transmission electron microscopy (TEM) and negative staining of thin-sectioned specimens, rendering them uninfectious. E-beam irradiation at doses greater than 10 kGy was also found to degrade viral genomic RNA by qRT-PCR. There were no significant differences in color, pH, TVB-N, TBARS, and sensory properties of irradiated fish samples at doses below 10 kGy. These findings suggested that E-beam irradiation has the potential to be developed as an efficient non-thermal treatment to reduce SARS-CoV-2 contamination in foods transported through cold chain foods to reduce the risk of SARS-CoV-2 infection in humans through the cold chain.

7.
Clin Infect Dis ; 2022 Jul 23.
Article in English | MEDLINE | ID: covidwho-2004984

ABSTRACT

BACKGROUND: Acceleration of negative respiratory conversion of SARS-CoV-2 in patients with coronavirus disease 2019 (COVID-19) might reduce viral transmission. Nirmatrelvir/ritonavir is a new antiviral agent recently approved for treatment of COVID-19 that has the potential to facilitate negative conversion. METHODS: A cohort of hospitalized adult patients with mild-to-moderate COVID-19 who had a high-risk for progression to severe disease were studied. These patients presented with COVID-19 symptoms between March 5 and April 5, 2022. The time from positive to negative upper respiratory RT-PCR conversion was assessed by Kaplan-Meier plots and Cox proportional hazards regression with the adjustment for patients baseline demographic and clinical characteristics. RESULTS: There were 258 patients treated with nirmatrelvir/ritonavir and 224 non-treated patients who had mild-to-moderate COVID-19. The median (interquartile range) time for patients who converted from positive to negative RT-PCR was 10 days (7-12 days) in patients treated ≤5 days after symptom onset and 17 days (12-21 days) in non-treated patients, respectively. The proportions of patients with a negative conversion at day 15 were 89.7% and 42.0% in treated patients and non-treated patients, corresponding to a hazard ratio of 4.33 (95% CI, 3.31-5.65). Adjustment for baseline differences between the groups had little effect on the association. Subgroup analysis on treated patients suggests that time to negative conversion did not vary with the patients' baseline characteristics. CONCLUSION: This cohort study of high-risk patients with mild-to-moderate COVID-19 found an association between nirmatrelvir/ritonavir treatment and accelerated negative RT-PCR respiratory SARS-CoV-2 conversion that might reduce the risk of viral shedding and disease transmission.

8.
Journal of Shandong University ; 58(10):60-65, 2020.
Article in Chinese | CAB Abstracts | ID: covidwho-1975284

ABSTRACT

Objective: To investigate the risk factors of severe and critical patients with coronavirus disease 2019(COVID-19)in Hubei, China. Methods All patients with COVID-19 registered in the National Legal Infectious Disease Reporting System of Hubei Provincial Center for Disease Control and Prevention, as of March 18, 2020, were recruited. According to the symptoms, the patients were divided into two groups: mild/moderate patients and severe/critical patients. Their general characteristics were described, and the risk factors of severe and critical patients with COVID-19 were explored by using a Logistic regression model. Results A total of 48 814 cases were included, of which 38 730 were mild/moderate patients and 10 084 were severe/critical patients. The median age was 54(41, 65)years. Multivariate analysis showed that the elderly, male, home workers, people in Wuhan City, migrants, longer interval between onset and diagnosis, low temperature, higher concentrations of PM2.5/PM10/SO2/O3 increased the risk of severe/critical diagnosis in patients with COVID-19. Conclusion The elderly, male, home workers, people in Wuhan City, migrants, longer interval between onset and diagnosis, low temperature, and air pollution exposure are risk factors for severe/critical COVID-19 patients. More attention should be paid to people with these characteristics.

9.
BMC Med Imaging ; 22(1): 135, 2022 07 30.
Article in English | MEDLINE | ID: covidwho-1968552

ABSTRACT

BACKGROUND: Corona Virus Disease 2019 (COVID-19) first appeared in December 2019, and spread rapidly around the world. COVID-19 is a pneumonia caused by novel coronavirus infection in 2019. COVID-19 is highly infectious and transmissible. By 7 May 2021, the total number of cumulative number of deaths is 3,259,033. In order to diagnose the infected person in time to prevent the spread of the virus, the diagnosis method for COVID-19 is extremely important. To solve the above problems, this paper introduces a Multi-Level Enhanced Sensation module (MLES), and proposes a new convolutional neural network model, MLES-Net, based on this module. METHODS: Attention has the ability to automatically focus on the key points in various information, and Attention can realize parallelism, which can replace some recurrent neural networks to a certain extent and improve the efficiency of the model. We used the correlation between global and local features to generate the attention mask. First, the feature map was divided into multiple groups, and the initial attention mask was obtained by the dot product of each feature group and the feature after the global pooling. Then the attention masks were normalized. At the same time, there were two scaling and translating parameters in each group so that the normalize operation could be restored. Then, the final attention mask was obtained through the sigmoid function, and the feature of each location in the original feature group was scaled. Meanwhile, we use different classifiers on the network models with different network layers. RESULTS: The network uses three classifiers, FC module (fully connected layer), GAP module (global average pooling layer) and GAPFC module (global average pooling layer and fully connected layer), to improve recognition efficiency. GAPFC as a classifier can obtain the best comprehensive effect by comparing the number of parameters, the amount of calculation and the detection accuracy. The experimental results show that the MLES-Net56-GAPFC achieves the best overall accuracy rate (95.27%) and the best recognition rate for COVID-19 category (100%). CONCLUSIONS: MLES-Net56-GAPFC has good classification ability for the characteristics of high similarity between categories of COVID-19 X-Ray images and low intra-category variability. Considering the factors such as accuracy rate, number of network model parameters and calculation amount, we believe that the MLES-Net56-GAPFC network model has better practicability.


Subject(s)
COVID-19 , Deep Learning , COVID-19/diagnostic imaging , Humans , Neural Networks, Computer , SARS-CoV-2 , X-Rays
10.
Front Microbiol ; 13: 948770, 2022.
Article in English | MEDLINE | ID: covidwho-1933720

ABSTRACT

Toll-like receptors (TLRs) are key sensors that recognize the pathogen-associated molecular patterns (PAMPs) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to activate innate immune response to clear the invading virus. However, dysregulated immune responses may elicit the overproduction of proinflammatory cytokines and chemokines, resulting in the enhancement of immune-mediated pathology. Therefore, a proper understanding of the interaction between SARS-CoV-2 and TLR-induced immune responses is very important for the development of effective preventive and therapeutic strategies. In this review, we discuss the recognition of SARS-CoV-2 components by TLRs and the downstream signaling pathways that are activated, as well as the dual role of TLRs in regulating antiviral effects and excessive inflammatory responses in patients with coronavirus disease 2019 (COVID-19). In addition, this article describes recent progress in the development of TLR immunomodulators including the agonists and antagonists, as vaccine adjuvants or agents used to treat hyperinflammatory responses during SARS-CoV-2 infection.

11.
Chin Med J (Engl) ; 135(11): 1314-1324, 2022 Jun 05.
Article in English | MEDLINE | ID: covidwho-1931923

ABSTRACT

ABSTRACT: A large-scale vaccination of coronavirus disease-19 (COVID-19) in adults has been conducted for nearly a year, and there is a growing recognition that immunization for children is also essential. It has been months since emergency use of pediatric COVID-19 vaccine was approved, we reviewed the prevalence and transmission of COVID-19 in children. The prevalence of COVID-19 in children is reduced due to vaccination even in a Delta prevalent period, so an increase in the vaccination rate is needed in children. Although the precise role of children in the transmission requires more research to uncover, they likely played a significant role, according to the available literature. We also described four candidate COVID-19 vaccines for children on their safety and immunogenicity and the impact of severe acute respiratory syndrome coronavirus 2 variants on childhood vaccination. Safety issues on pediatric vaccines post-approval, like adverse events following immunization and adverse events of special interest require studies on long-term and effective regulatory mechanisms.


Subject(s)
COVID-19 Vaccines , COVID-19 , COVID-19/prevention & control , COVID-19 Vaccines/adverse effects , COVID-19 Vaccines/therapeutic use , Child , Humans , SARS-CoV-2 , Vaccination
12.
Ionics (Kiel) ; 28(7): 3489-3500, 2022.
Article in English | MEDLINE | ID: covidwho-1899299

ABSTRACT

The massive global consumption and discarded face masks drove by the ongoing spread of COVID-19. Meantime, incineration and landfill discarded face masks would result in severe environmental pollution and infectious hazards. Herein a suggestion to recycle polypropylene waste masks into CNTs by an environmentally friendly and high-added value disposal process was proposed, and which was prepared as supercapacitor electrode materials for energy storage attempting. The CNTs were prepared from waste masks by catalysis pyrolysis with Ni-Fe bimetallic catalysts. Especially, the bamboo-like structure CNT was obtained with Ni/Fe molar ratio is 3. This structure owned a high specific capacitance compared to other standard CNTs. Its specific capacitance could reach 56.04 F/g (1 A/g) and has excellent cycling stability with a capacitance retention rate of the material is 85.41% after 10,000 cycles. Besides, the assembled capacitor possesses a good energy density of 4.78 Wh/kg at a power density of 900 W/kg. Thus, this work provides a sustainable and cost-effective strategy for disposing waste masks into high-valuable CNT, and their potential application for supercapacitors was also studied and exploited. It would provide a new idea for recycling and utilizing other polypropylene wastes such as medical devices.

13.
Immunohorizons ; 6(6): 344-355, 2022 06 13.
Article in English | MEDLINE | ID: covidwho-1893080

ABSTRACT

Epitope mapping of the interactions between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and Abs is challenging because of complexity in protein three-dimensional structures. Protein structure fingerprint technology was applied for epitope mapping of 44 SARS-CoV-2 Abs with three-dimensional structure complexes. The results defined how the epitopes were distributed on SARS-CoV-2 and how the patterns of six CDRs from Abs participated in neutralization. Also, the residue-residue recognition revealed that certain residues had higher frequencies on the interfaces between SARS-CoV-2 and Abs, and the activity correlated with the physicochemical properties of the residues at the interface. Thus, epitope mapping provides significant lead information for development of epitope-based designs for Abs, vaccines, and diagnostic reagents. This is a bioinformatics project of structural data analysis; no animals or cells were used.


Subject(s)
COVID-19 , SARS-CoV-2 , Antibodies, Viral , Epitope Mapping , Epitopes , Humans , Membrane Glycoproteins , Spike Glycoprotein, Coronavirus , Viral Envelope Proteins
14.
J Exp Med ; 219(7)2022 07 04.
Article in English | MEDLINE | ID: covidwho-1878728

ABSTRACT

Autosomal recessive IRF7 deficiency was previously reported in three patients with single critical influenza or COVID-19 pneumonia episodes. The patients' fibroblasts and plasmacytoid dendritic cells produced no detectable type I and III IFNs, except IFN-ß. Having discovered four new patients, we describe the genetic, immunological, and clinical features of seven IRF7-deficient patients from six families and five ancestries. Five were homozygous and two were compound heterozygous for IRF7 variants. Patients typically had one episode of pulmonary viral disease. Age at onset was surprisingly broad, from 6 mo to 50 yr (mean age 29 yr). The respiratory viruses implicated included SARS-CoV-2, influenza virus, respiratory syncytial virus, and adenovirus. Serological analyses indicated previous infections with many common viruses. Cellular analyses revealed strong antiviral immunity and expanded populations of influenza- and SARS-CoV-2-specific memory CD4+ and CD8+ T cells. IRF7-deficient individuals are prone to viral infections of the respiratory tract but are otherwise healthy, potentially due to residual IFN-ß and compensatory adaptive immunity.


Subject(s)
COVID-19 , Influenza, Human , Virus Diseases , Viruses , Adult , COVID-19/genetics , Humans , Influenza, Human/genetics , SARS-CoV-2
15.
EuropePMC; 2022.
Preprint in English | EuropePMC | ID: ppcovidwho-337035

ABSTRACT

Pediatric SARS-CoV-2 vaccines are needed that elicit immunity directly in the airways, as well as systemically. Building on pediatric parainfluenza virus vaccines in clinical development, we generated a live-attenuated parainfluenza virus-vectored vaccine candidate expressing SARS-CoV-2 prefusion-stabilized spike (S) protein (B/HPIV3/S-6P) and evaluated its immunogenicity and protective efficacy in rhesus macaques. A single intranasal/intratracheal dose of B/HPIV3/S-6P induced strong S-specific airway mucosal IgA and IgG responses. High levels of S-specific antibodies were also induced in serum, which efficiently neutralized SARS-CoV-2 variants of concern. Furthermore, B/HPIV3/S-6P induced robust systemic and pulmonary S-specific CD4 + and CD8 + T-cell responses, including tissue-resident memory cells in lungs. Following challenge, SARS-CoV-2 replication was undetectable in airways and lung tissues of immunized macaques. B/HPIV3/S-6P will be evaluated clinically as pediatric intranasal SARS-CoV-2/parainfluenza virus type 3 vaccine.

16.
Nat Biotechnol ; 40(6): 840-854, 2022 06.
Article in English | MEDLINE | ID: covidwho-1830079

ABSTRACT

The emergency use authorizations (EUAs) of two mRNA-based severe acute respiratory syndrome coronavirus (SARS-CoV)-2 vaccines approximately 11 months after publication of the viral sequence highlights the transformative potential of this nucleic acid technology. Most clinical applications of mRNA to date have focused on vaccines for infectious disease and cancer for which low doses, low protein expression and local delivery can be effective because of the inherent immunostimulatory properties of some mRNA species and formulations. In addition, work on mRNA-encoded protein or cellular immunotherapies has also begun, for which minimal immune stimulation, high protein expression in target cells and tissues, and the need for repeated administration have led to additional manufacturing and formulation challenges for clinical translation. Building on this momentum, the past year has seen clinical progress with second-generation coronavirus disease 2019 (COVID-19) vaccines, Omicron-specific boosters and vaccines against seasonal influenza, Epstein-Barr virus, human immunodeficiency virus (HIV) and cancer. Here we review the clinical progress of mRNA therapy as well as provide an overview and future outlook of the transformative technology behind these mRNA-based drugs.


Subject(s)
COVID-19 , Epstein-Barr Virus Infections , Influenza Vaccines , COVID-19/prevention & control , COVID-19 Vaccines/therapeutic use , Herpesvirus 4, Human , Humans , Immunization, Secondary , RNA, Messenger/genetics , Vaccines, Synthetic , mRNA Vaccines
17.
mBio ; 13(3): e0018122, 2022 06 28.
Article in English | MEDLINE | ID: covidwho-1816698

ABSTRACT

Understanding immune memory to COVID-19 vaccines is critical for the design and optimal vaccination schedule for curbing the COVID-19 pandemic. Here, we assessed the status of humoral and cellular immune responses at 1, 3, 6, and 12 months after two-dose CoronaVac vaccination. A total of 150 participants were enrolled, and 136 of them completed the study through the 12-month endpoint. Our results show that, at 1 month after vaccination, both binding and neutralizing antibodies could be detected; the seropositive rate of binding antibodies and seroconversion rate of neutralizing antibodies were 99% and 50%, respectively. From 3 to 12 months, the binding and neutralizing antibodies declined over time. At 12 months, the binding and neutralizing antibodies were still detectable and significantly higher than the baseline. Gamma interferon (IFN-γ) and interleukin 2 (IL-2) secretion specifically induced by the receptor-binding domain (RBD) persisted at high levels until 6 months and could be observed at 12 months, while the levels of IL-5 and granzyme B (GzmB) were hardly detected, demonstrating a Th1-biased response. In addition, specific CD4+ T central memory (TCM), CD4+ effector memory (TEM), CD8+ TEM, and CD8+ terminal effector (TE) cells were all detectable and functional up to 12 months after the second dose, as the cells produced IFN-γ, IL-2, and GzmB in response to stimulation of SARS-CoV-2 RBD. Our work provides evidence that CoronaVac induced not only detectable binding and neutralizing antibody responses, but also functional SARS-CoV-2-specific CD4+ and CD8+ memory T cells for up to 12 months. IMPORTANCE CoronaVac is an inactivated vaccine containing whole-virion SARS-CoV-2, which has been approved in 43 countries for emergency use as of 26 November 2021. However, the long-term immune persistence of the CoronaVac vaccine is still unknown. Here, we reported the status of the persistence of antibodies and cellular responses within 12 months after two doses of CoronaVac. Such data are crucial to inform ongoing and future vaccination strategies to combat COVID-19.


Subject(s)
COVID-19 Vaccines , COVID-19 , Immunity, Cellular , Immunity, Humoral , Vaccines, Inactivated , Antibodies, Neutralizing , Antibodies, Viral , CD8-Positive T-Lymphocytes , COVID-19/prevention & control , COVID-19 Vaccines/immunology , Humans , Interleukin-2 , Pandemics , SARS-CoV-2 , Vaccination , Vaccines, Inactivated/immunology
18.
Int J Environ Res Public Health ; 19(8)2022 04 17.
Article in English | MEDLINE | ID: covidwho-1809884

ABSTRACT

Plastic debris contamination in marine environments is a global problem that poses a considerable threat to the sustainability and health of coastal ecosystems. Marine beaches, as the key zones where terrestrial plastic debris reach coastal waters, are faced with the increasing pressures of human activities. In this study, we explored the distribution, composition, and inventory of plastic debris over seasonal and tidal zones at the Yugang Park Beach (YPB) in Zhanjiang Bay, South China Sea, to provide a baseline for plastic debris on a marine beach. The results showed mean abundance of plastic debris in summer (6.00 ± 2.10 items/m2) was significantly greater than that in winter (3.75 ± 2.12 items/m2). In addition, the composition of plastic debris ranged in size mainly from 1 to 5 mm and 0.5 to 2.5 cm in winter and summer, respectively. In terms of composition, white plastic debris was the most common (81.1%), and foam was the most abundant (64.4%). Moreover, there was a significant relationship between the abundance of plastic debris and sand grain size fraction (p < 0.05), implying the abundances of microplastic debris were more easily impacted by sand grain size (>2 mm). In total inventory, there were about 1.18 × 105 and 2.95 × 105 items of plastic debris on the YPB in winter and summer, respectively. The tidal variation and human activities are responsible for the plastic debris accumulation. This study provided a method to quantify the inventory of plastic debris on a beach and could be helpful to consider regional tidal variations and critical source areas for effective plastic debris clean-up.


Subject(s)
Bathing Beaches , Plastics , Bays , Ecosystem , Environmental Monitoring/methods , Humans , Sand , Seasons , Waste Products/analysis
19.
EuropePMC; 2022.
Preprint in English | EuropePMC | ID: ppcovidwho-334201

ABSTRACT

ABSTRACT Pre-mRNA splicing is initiated with the recognition of a single-nucleotide intronic branchpoint (BP) within a BP motif by spliceosome elements. Fifty-six rare variants in 44 human genes have been reported to alter splicing and cause disease by disrupting BP. However, until now, no computational approach has been available to efficiently detect such variants in next-generation sequencing (NGS) data. We established a comprehensive human genome-wide BP database by integrating existing BP data, and by generating new BP data from RNA-seq of lariat debranching enzyme DBR1-mutated patients and from machine-learning predictions. We in-depth characterize multiple features of BP in major and minor introns, and find that BP and BP-2 (two-nucleotides upstream of BP) positions exhibit a lower rate of variation in human populations and higher evolutionary conservation than the intronic background, whilst being comparable to the exonic background. We develop BPHunter as a genome-wide computational approach to systematically and efficiently detect intronic variants that may disrupt BP recognition in NGS data. BPHunter retrospectively identifies 48 of the 56 known pathogenic BP mutations in which we summarize a strategy for prioritizing BP mutation candidates, and the remaining 8 all create AG dinucleotides between BP and acceptor site which is probably the reason for mis-splicing. We demonstrate the utility of BPHunter prospectively by using it to identify a novel germline heterozygous BP variant of STAT2 in a patient with critical COVID-19 pneumonia, and a novel somatic intronic 59-nucleotide deletion of ITPKB in a lymphoma patient, both of which we validate experimentally. BPHunter is publicly available from https://hgidsoft.rockefeller.edu/BPHunter and https://github.com/casanova-lab/BPHunter .

20.
IET Image Process ; 16(8): 2101-2113, 2022 Jun 19.
Article in English | MEDLINE | ID: covidwho-1740500

ABSTRACT

Currently, coronavirus disease 2019 (COVID-19) has not been contained. It is a safe and effective way to detect infected persons in chest X-ray (CXR) images based on deep learning methods. To solve the above problem, the dual-path multi-scale fusion (DMFF) module and dense dilated depth-wise separable (D3S) module are used to extract shallow and deep features, respectively. Based on these two modules and multi-scale spatial attention (MSA) mechanism, a lightweight convolutional neural network model, MSA-DDCovidNet, is designed. Experimental results show that the accuracy of the MSA-DDCovidNet model on COVID-19 CXR images is as high as 97.962%, In addition, the proposed MSA-DDCovidNet has less computation complexity and fewer parameter numbers. Compared with other methods, MSA-DDCovidNet can help diagnose COVID-19 more quickly and accurately.

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