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1.
Proc Natl Acad Sci U S A ; 121(31): e2404595121, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39047040

RESUMO

New particle formation (NPF) substantially affects the global radiation balance and climate. Iodic acid (IA) is a key marine NPF driver that recently has also been detected inland. However, its impact on continental particle nucleation remains unclear. Here, we provide molecular-level evidence that IA greatly facilitates clustering of two typical land-based nucleating precursors: dimethylamine (DMA) and sulfuric acid (SA), thereby enhancing particle nucleation. Incorporating this mechanism into an atmospheric chemical transport model, we show that IA-induced enhancement could realize an increase of over 20% in the SA-DMA nucleation rate in iodine-rich regions of China. With declining anthropogenic pollution driven by carbon neutrality and clean air policies in China, IA could enhance nucleation rates by 1.5 to 50 times by 2060. Our results demonstrate the overlooked key role of IA in continental NPF nucleation and highlight the necessity for considering synergistic SA-IA-DMA nucleation in atmospheric modeling for correct representation of the climatic impacts of aerosols.

2.
Brief Bioinform ; 25(3)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38653491

RESUMO

Coronaviruses have threatened humans repeatedly, especially COVID-19 caused by SARS-CoV-2, which has posed a substantial threat to global public health. SARS-CoV-2 continuously evolves through random mutation, resulting in a significant decrease in the efficacy of existing vaccines and neutralizing antibody drugs. It is critical to assess immune escape caused by viral mutations and develop broad-spectrum vaccines and neutralizing antibodies targeting conserved epitopes. Thus, we constructed CovEpiAb, a comprehensive database and analysis resource of human coronavirus (HCoVs) immune epitopes and antibodies. CovEpiAb contains information on over 60 000 experimentally validated epitopes and over 12 000 antibodies for HCoVs and SARS-CoV-2 variants. The database is unique in (1) classifying and annotating cross-reactive epitopes from different viruses and variants; (2) providing molecular and experimental interaction profiles of antibodies, including structure-based binding sites and around 70 000 data on binding affinity and neutralizing activity; (3) providing virological characteristics of current and past circulating SARS-CoV-2 variants and in vitro activity of various therapeutics; and (4) offering site-level annotations of key functional features, including antibody binding, immunological epitopes, SARS-CoV-2 mutations and conservation across HCoVs. In addition, we developed an integrated pipeline for epitope prediction named COVEP, which is available from the webpage of CovEpiAb. CovEpiAb is freely accessible at https://pgx.zju.edu.cn/covepiab/.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19 , Epitopos , SARS-CoV-2 , Humanos , SARS-CoV-2/imunologia , SARS-CoV-2/genética , Anticorpos Antivirais/imunologia , COVID-19/imunologia , COVID-19/virologia , Anticorpos Neutralizantes/imunologia , Epitopos/imunologia , Epitopos/química , Epitopos/genética , Coronavirus/imunologia , Coronavirus/genética , Bases de Dados Factuais , Reações Cruzadas/imunologia
3.
Appl Opt ; 63(10): A70-A77, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38568513

RESUMO

Tungsten oxide (W O 3) has been widely used in hydrogen sensing due to its stable chemical properties and high oxygen vacancy diffusion coefficient. However, the response of pure W O 3 to hydrogen is slow, and doping is an effective way to improve the hydrogen sensing performance of W O 3 materials. In this paper, W O 3/P t/P E G/S i O 2 porous film was prepared by the sol-gel method using tungsten powder, H 2 O 2 and C 2 H 5 O H as precursors, polyethylene glycol (PEG) as the pore-forming agent, and tetraethyl orthosilicate (TEOS) as the S i O 2 source material. The sensing properties of the W O 3 composite for hydrogen were characterized by a transmission optical fiber hydrogen sensing system made at home. The process parameters such as water bath time, aging time, W:PEG ratio, and W:TEOS ratio were optimized to improve the sensitivity and response time of the sensing film. The experimental results indicate that the sensitivity is 15.68%, the average response time is 45 s, and the repeatability is up to 98.74% in 16 consecutive tests. The linearity index R 2 is 0.9946 within the hydrogen concentration range of 5000 ppm to 50,000 ppm. The film responds only to H 2 when the concentration of interfering gases (C H 4, CO, C O 2) is 2000 ppm. The hydrogen sensing performance of the optimized film is significantly improved compared with that of the undoped film.

4.
Small ; 19(43): e2300242, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37381614

RESUMO

Graphene with a 3D porous structure is directly laser-induced on lignocellulosic biopaper under ambient conditions and is further explored for multifunctional biomass-based flexible electronics. The mechanically strong, flexible, and waterproof biopaper is fabricated by surface-functionalizing cellulose with lignin-based epoxy acrylate (LBEA). This composite biopaper shows as high as a threefold increase in tensile strength and excellent waterproofing compared with pure cellulose one. Direct laser writing (DLW) rapidly induces porous graphene from the biopaper in a single step. The porous graphene shows an interconnected carbon network, well-defined graphene domains, and high electrical conductivity (e.g., ≈3 Ω per square), which can be tuned by lignin precursors and loadings as well as lasing conditions. The biopaper in situ embedded with porous graphene is facilely fabricated into flexible electronics for on-chip and paper-based applications. The biopaper-based electronic devices, including the all-solid-state planer supercapacitor, electrochemical and strain biosensors, and Joule heater, show great performances. This study demonstrates the facile, versatile, and low-cost fabrication of multifunctional graphene-based electronics from lignocellulose-based biopaper.

5.
Environ Res ; 219: 115138, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36565844

RESUMO

Growing evidence indicated an association between PM2.5 exposure and cognitive function, but the causal effect and the cognitive effect of prenatal PM2.5 exposure remain elusive. We obtained 15,099 subjects from a nationally representative sample of China and measured their cognitive performance. We ascertained subjects' prenatal PM2.5 exposure and chronic PM2.5 exposure of the recent two years. Using this national sample, we found that PM2.5 exposure during the mid- to late-pregnancy was significantly associated with declined cognition and income; chronic PM2.5 exposure was also independently associated with cognition and income measured at adulthood with greater magnitude. Negative effect modification was observed between prenatal and chronic PM2.5 exposure. Instrumental variable approach and difference-in-difference study verified causal effects: every 1 µg/m3 increase in prenatal and chronic PM2.5 exposures were causally associated with -0.22% (-0.38%, -0.06%) and -0.17% (-0.31%, -0.03%) changes in cognitive function, respectively. People with low cognition and low income were more vulnerable to PM2.5 exposure with greater cognitive and income decline. In the future, although China's improved air quality continues to benefit people and reduce cognitive decline induced by chronic PM2.5 exposure, high prenatal PM2.5 exposure will continue to hurt the overall cognition of Chinese population, since in total 360 million people were born during the 2000-2020 polluted era. Prenatal PM2.5-induced cognitive decline would remain largely unchanged before 2050 and gradually reduce after 2065, regardless of environmental policy scenarios. The long-lasting cognitive impact of PM2.5 is worth considering while enacting environmental policies.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Feminino , Humanos , Gravidez , Adulto , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/análise , Material Particulado/toxicidade , Material Particulado/análise , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Vitaminas , Cognição
6.
Biol Pharm Bull ; 37(4): 608-17, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24694607

RESUMO

Cordycepol C, a novel sesquiterpene isolated from the cultured mycelia of Cordyceps ophioglossoides, contains a hydroperoxy group and is cytotoxic to HepG2 cells. So far, no sesquiterpenes have been found in the genus Cordyceps and it would be interesting to investigate the antitumor efficacy as well as the mechanism of action of this unusual sesquiterpene. In this study, we showed that cordycepol C induced apoptosis of the HepG2 cells without affecting the normal liver cell line L-02. Cordycepol C caused poly(ADP-ribose)polymerase-1 (PARP-1) cleavage and triggered the loss of mitochondrial membrane potential (Δψm) in HepG2 cells in a time- and dose-dependent manner, resulting in the nuclear translocation of apoptosis-inducing factor (AIF) and endonuclease G (Endo G). We also found that cordycepol C induced the expression of Bax protein, followed by its translocation from the cytosol to mitochondria in both wild type and p53 knockdown HepG2 cells. However, cordycepol C could not cause cleavages of procaspase-3, -8, and -9. Caspase activities were not increased and Z-VAD-fmk, a caspase inhibitor, could not prevent the apoptosis induced by cordycepol C. These findings indicate that cordycepol C induces caspase-independent apoptosis in HepG2 cells through a p53-independent and Bax-mediated mitochondrial pathway, leading to the nuclear translocation of AIF and Endo G. Our study provides the molecular mechanism by which cordycepol C induces apoptosis in hepatocellular carcinoma cells and indicates the potential use of cordycepol C as an antitumor agent.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/patologia , Caspases/metabolismo , Neoplasias Hepáticas/patologia , Sesquiterpenos/farmacologia , Clorometilcetonas de Aminoácidos/farmacologia , Fator de Indução de Apoptose/metabolismo , Carcinoma Hepatocelular/tratamento farmacológico , Caspase 3/metabolismo , Caspase 9/metabolismo , Inibidores de Caspase/farmacologia , Linhagem Celular , Endodesoxirribonucleases/metabolismo , Técnicas de Silenciamento de Genes , Células Hep G2 , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Poli(ADP-Ribose) Polimerases/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína X Associada a bcl-2/metabolismo
7.
Vaccine X ; 16: 100444, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38327768

RESUMO

Although the global pandemic of SARS-CoV-2 has passed, there are still regional outbreaks that continue to jeopardize human health. Hence, there is still a great deal of interest in developing an efficient vaccine that can quickly and effectively prevent reemerging outbreaks of SARS-CoV-2. Delta variant was once a dominant strain in the world in 2021, and we first constructed a recombinant RBDdelta-Fc fusion vaccine by coupling the RBD of Delta variant with the human Fc fragment. This Fc fusion strategy increases the immunogenicity of the recombinant RBD vaccine, with a long-lasting high level of IgG antibodies and neutralizing antibodies induced by RBDdelta-Fc vaccine. This RBDdelta-Fc vaccine, as well as the RBD-Fc vaccine prepared in our previously study, could trigger a durable immune effect by the heterologous boosting immunity, and the RBD-Fc induced a quicker humoral immune response than the homologous immunization with inactivated vaccines. In conclusion, the Fc fusion strategy has a significant role in enhancing the immunogenicity of recombinant protein vaccines, thus promising the development of a safe and efficient vaccine for the heterologous boosting against SARS-CoV-2.

8.
Natl Sci Rev ; 11(4): nwae007, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38495813

RESUMO

China currently has the highest acid deposition globally, yet research on its status, impacts, causes and controls is lacking. Here, we compiled data and calculated critical loads regarding acid deposition. The results showed that the abatement measures in China have achieved a sharp decline in the emissions of acidifying pollutants and a continuous recovery of precipitation pH, despite the drastic growth in the economy and energy consumption. However, the risk of ecological acidification and eutrophication showed no significant decrease. With similar emission reductions, the decline in areas at risk of acidification in China (7.0%) lags behind those in Europe (20%) or the USA (15%). This was because, unlike Europe and the USA, China's abatement strategies primarily target air quality improvement rather than mitigating ecological impacts. Given that the area with the risk of eutrophication induced by nitrogen deposition remained at 13% of the country even under the scenario of achieving the dual targets of air quality and carbon dioxide mitigation in 2035, we explored an enhanced ammonia abatement pathway. With a further 27% reduction in ammonia by 2035, China could largely eliminate the impacts of acid deposition. This research serves as a valuable reference for China's future acid deposition control and for other nations facing similar challenges.

9.
Eco Environ Health ; 3(1): 11-20, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38169841

RESUMO

The ambient air quality standard (AAQS) is a vital policy instrument for protecting the environment and human health. Hainan Province is at the forefront of China's efforts to protect its ecological environment, with an official goal to achieve world-leading air quality by 2035. However, neither the national AAQS nor the World Health Organization guideline offers sufficient guidance for improving air quality in Hainan because Hainan has well met the former while the latter is excessively stringent. Consequently, the establishment of Hainan's local AAQS becomes imperative. Nonetheless, research regarding the development of local AAQS is scarce, especially in comparatively more polluted countries such as China. The relatively high background values and significant interannual fluctuations in air pollutant concentrations in Hainan present challenges in the development of local AAQS. Our research proposes a world-class local AAQS of Hainan Province by reviewing the AAQS in major countries or regions worldwide, analyzing the influence of different statistical forms, and carefully evaluating the attainability of the standard. In the proposed AAQS, the annual mean concentration limit for PM2.5, the annual 95th percentile of daily maximum 8-h mean (MDA8) concentration limit for O3, and the peak season concentration limit for O3 are set at 10, 120, and 85 µg/m3, respectively. Our study indicates that, with effective control policies, Hainan is projected to achieve compliance with the new standard by 2035. The implementation of the local AAQS is estimated to avoid 1,526 (1,253-1,789) and 259 (132-501) premature deaths attributable to long-term exposure to PM2.5 and O3 in Hainan in 2035, respectively.

10.
Tissue Cell ; 82: 102048, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36905861

RESUMO

BACKGROUND: To clarify the research prospect and mechanism analysis of isorhamnetin as a therapeutic drug for bladder cancer. METHODS: Firstly, the effects of different concentrations of isorhamnetin on the expression of PPARγ/PTEN/Akt pathway protein, CA9, PPARγ, PTEN and AKT protein were discussed by western blot. The effects of isorhamnetin on the growth of bladder cells were also analyzed. Secondly, we verified whether the effect of isorhamnetin on CA9 was related to PPARγ/PTEN/Akt pathway by western blot, and the mechanism of isorhamnetin on the growth of bladder cells is related to this pathway by CCK8, cell cycle and ball formation experiment. Further, nude mouse model of subcutaneous tumor transplantation was constructed to analyze the effects of isorhamnetin, PPAR and PTEN on 5637 cell tumorigenesis and the effects of isorhamnetin on tumorigenesis and CA9 expression through PPARγ/PTEN/Akt pathway. RESULTS: Isorhamnetin inhibited the development of bladder cancer, and regulated the expression of PPAR, PTEN, AKT, CA9. Isorhamnetin inhibits cell proliferation and the transition of cells from G0/G1 phase to S phase, and tumor sphere formation. Carbonic anhydrase IX is a potential downstream molecule of PPARγ/PTEN/AKT pathway. Overexpression of PPARγ and PTEN inhibited expression of CA9 in bladder cancer cells and tumor tissues. Isorhamnetin reduced CA9 expression in bladder cancer via PPARγ/PTEN/AKT pathway, thereby inhibiting bladder cancer tumorigenicity. CONCLUSION: Isorhamnetin has the potential to become a therapeutic drug for bladder cancer, whose antitumor mechanism is related to PPARγ/PTEN/AKT pathway. Isorhamnetin reduced CA9 expression in bladder cancer via PPARγ/PTEN/AKT pathway, thereby inhibiting bladder cancer tumorigenicity.


Assuntos
PPAR gama , Neoplasias da Bexiga Urinária , Camundongos , Animais , Anidrase Carbônica IX/genética , Anidrase Carbônica IX/metabolismo , Anidrase Carbônica IX/farmacologia , PPAR gama/genética , PPAR gama/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Carcinogênese , Transformação Celular Neoplásica , Neoplasias da Bexiga Urinária/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células
11.
Int Immunopharmacol ; 124(Pt B): 111020, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37812969

RESUMO

As SARS-CoV-2 variants continue spreading globally, the discovery of broad spectrum therapeutically active antibodies with retaining good protective activity is a global priority. It was reported that infection with SARS-CoV-2 could cause acute lung injury (ALI) in clinical investigations. Therefore, we discovered that anti-RBD scFv is effective against SARS-CoV-2-induced ALI. To begin, we utilized the receptor binding domain (RBD) of spike glycoprotein as a target to produce single-chain antibodies (scFvs) through an intensive phage display technology. The binding affinity and inhibitory effect of the scFvs were evaluated via ELISA and flow cytometry. Moreover, anti-RBD scFv No.35 significantly prevented ALI caused by LPS and SARS-CoV-2 spike RBD protein in mouse model. Thus, the anti-RBD scFv will aid the development of potential antibody treatments and reduce the inflammatory response of SARS-CoV-2.


Assuntos
Lesão Pulmonar Aguda , Anticorpos de Cadeia Única , Animais , Camundongos , Anticorpos Antivirais/uso terapêutico , Ligação Proteica , Anticorpos de Cadeia Única/uso terapêutico , Lesão Pulmonar Aguda/tratamento farmacológico , Anticorpos Neutralizantes/uso terapêutico
12.
Huan Jing Ke Xue ; 44(7): 3627-3636, 2023 Jul 08.
Artigo em Zh | MEDLINE | ID: mdl-37438262

RESUMO

The Beijing-Tianjin-Hebei-Shandong Region (BTHS Region) is a crucial area for China to achieve synergy between pollution reduction and carbon emissions reduction. The demand for coordinated emissions reduction through source control measures such as energy transition and industrial restructuring are becoming increasingly necessary owing to the limited emissions reductions potential of end-of-pipe control measures. An assessment of the emissions reductions potential through strengthening the end-of-pipe control in the BTHS Region, as well as the environmental and health co-benefits from accelerated energy transition and industrial restructuring, was conducted using scenario simulation analysis based on the REACH model. The results showed that the rapid implementation of the best available end-of-pipe control technologies in the BTHS Region would result in 3.3 µg·m-3 reduction in PM2.5 concentration in 2035, but this would not be sufficient to achieve the PM2.5 concentration control targets. Accelerating the energy transition and the industrial restructuring are necessary for the BTHS Region to achieve air quality standards, which would reduce the PM2.5 concentrations by 6.3 µg·m-3 in 2035. The environmental and health co-benefits brought by the accelerated transition could partially or entirely offset the additional socio-economic cost (compared to that of the current policy efforts) of approximately 0.9%-2.5% of the total regional GDP in achieving the PM2.5 concentration control target paid by the four provinces.

13.
J Inflamm Res ; 16: 1867-1877, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37143821

RESUMO

Background: SARS-CoV-2-induced acute lung injury but its nucleocapsid (N) and/or Spike (S) protein involvements in the disease pathology remain elusive. Methods: In vitro, the cultured THP-1 macrophages were stimulated with alive SARS-CoV-2 virus at different loading dose, N protein or S protein with/without TICAM2-siRNA, TIRAP-siRNA or MyD88-siRNA. The TICAM2, TIRAP and MyD88 expression in the THP-1 cells after N protein stimulation were determined. In vivo, naïve mice or mice with depletion macrophages were injected with N protein or dead SARS-CoV-2. The macrophages in the lung were analyzed with flow cytometry, and lung sections were stained with H&E or immunohistochemistry. Culture supernatants and serum were harvested for cytokines measurements with cytometric bead array. Results: Alive SARS-CoV-2 virus or N protein but not S protein induced high cytokine releases from macrophages in a time or virus loading dependent manner. MyD88 and TIRAP but not TICAM2 were highly involved in macrophage activation triggered by N protein whilst both inhibited with siRNA decreased inflammatory responses. Moreover, N protein and dead SARS-CoV-2 caused systemic inflammation, macrophage accumulation and acute lung injury in mice. Macrophage depletion in mice decreased cytokines in response to N protein. Conclusion: SARS-CoV-2 and its N protein but not S protein induced acute lung injury and systemic inflammation, which was closely related to macrophage activation, infiltration and release cytokines.

14.
RSC Adv ; 12(46): 30030-30040, 2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36329928

RESUMO

Lignin-containing nanocelluloses (LNCs) have attracted tremendous research interest in recent years due to less complex extraction processes and more abundant functionality compared to lignin-free nanocelluloses. On the other hand, traditional defibrillation primarily based on bleached pulp would not be readily applied to lignin-containing pulps due to their complex compositions. This study was focused on LNC extraction from lignin-containing pulp via 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO)-mediated oxidation. Three types of switchgrass pulp with varying composition were prepared using different acid-catalyzed pretreatments. The pulps contained as high as 45.76% lignin but minor/no hemicellulose, corresponding to up to 23.72% lignin removal and 63.75-100% hemicellulose removal. TEMPO-mediated oxidation yielded 52.9-81.9% LNCs from respective pulps. The as-produced LNCs possessed aspect ratios as high as 416.5, and carboxyl contents of 0.442-0.743 mmol g-1 along with ζ-potential of -50.4 to -38.3 mV. The TEMPO-oxidized LNCs were further modified by polyethylenimine (PEI), which endowed the LNCs with positive charges plus antioxidant and antibacterial activities. Specifically, the PEI-modified LNCs almost fully scavenged 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) radicals at 50 mg L-1 and suppressed the growth of Gram-positive Staphylococcus aureus at 250 µg mL-1.

15.
Eur J Hum Genet ; 30(8): 922-929, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35322240

RESUMO

The human leucocyte antigen (HLA) loci have been widely characterized to be associated with viral infectious diseases using either HLA allele frequency-based association or in silico predicted studies. However, there is less experimental evidence to link the HLA alleles with COVID-19 and other respiratory infectious diseases, particularly in the lung cells. To examine the role of HLA alleles in response to coronavirus and other respiratory viral infections in disease-relevant cells, we designed a two-stage study by integrating publicly accessible RNA-seq data sets, and performed allelic expression (AE) analysis on heterozygous HLA genotypes. We discovered an increased AE pattern accompanied with overexpression of HLA-B gene in SARS-CoV-2-infected human lung epithelial cells. Analysis of independent data sets verified the respiratory virus-induced AE of HLA-B gene in lung cells and tissues. The results were further experimentally validated in cultured lung cells infected with SARS-CoV-2. We further uncovered that the antiviral cytokine IFNß contribute to AE of the HLA-B gene in lung cells. Our analyses provide a new insight into allelic influence on the HLA expression in association with SARS-CoV-2 and other common viral infectious diseases.


Assuntos
COVID-19 , SARS-CoV-2 , Desequilíbrio Alélico , COVID-19/genética , Antígenos HLA/genética , Antígenos HLA-B/genética , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Pulmão
16.
ACS Omega ; 7(45): 41548-41558, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36406527

RESUMO

Lignin-containing nanocelluloses (LNCs) have the properties of both lignin and nanocellulose and could overcome the limits of both individual components in metallic nanoparticle synthesis. However, studies on LNCs are still limited, and the potential of such nanomaterials for metallic nanoparticle synthesis has not been fully unraveled. In this study, monometallic silver, gold nanoparticles, and Ag-Au-AgCl nanohybrids were synthesized in situ utilizing LNCs in a chemical-free approach. The parameters, including Ag+ and Au3+ concentrations as well as [Au3+]/[Ag+] ratios, were investigated for their effects on the nanoparticle synthesis. The characterizations, including UV-vis spectrophotometry, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), X-ray powder diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR), confirmed the coexistence of Ag, Au, and AgCl while indicating the key role of lignin and oxygen-containing functional groups in the nanoparticle synthesis. The as-synthesized AgNPs-, AuNPs-, and nanohybrids-LNC samples were tested for their antibacterial activities. In comparison to the monometallic AgNPs-LNC sample, nanohybrids-LNC synthesized with 0.063 mM Au3+ loading showed superior antibacterial activities with minimum inhibitory concentrations (MICs) at 5 µg/mL against Gram-positive Staphylococcus aureus and 10 µg/mL against Gram-negative Salmonella typhimurium with controlled Ag+ release. The results indicated that LNCs can be used to synthesize metallic nanoparticles, and the resultant Ag-Au-AgCl nanohybrids were a potent antibacterial agent with reduced environmental impacts.

17.
Emerg Microbes Infect ; 11(1): 1994-2006, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35787233

RESUMO

Coxsackievirus A16 (CVA16) is one of the major pathogens responsible for human hand, foot, and mouth disease (HFMD), which has threatened the health of young children, particularly in Asia-Pacific nations. Vaccination is an effective strategy for protecting children from CVA16 infection. However, there is currently no licensed CVA16 vaccine for use in humans. In this study, we isolated a high-growth CVA16 virus strain in MRC-5 cells and developed an MRC-5-adapted vaccine candidate strain termed CVA16-393 via two rounds of plaque purification. The CVA16-393 strain was grouped into the B1b subgenotype and grew to a titre of over 107 TCID50/ml in MRC-5 cells. The VP1 gene region of this strain, which contains the major neutralizing epitopes, displayed high stability during serial passages. The inactivated whole-virus vaccine produced by the CVA16-393 strain induced an effective neutralizing antibody response in Meriones unguiculatus (gerbils) after two doses of intraperitoneal inoculation. One week after the booster immunization, the geometric mean titres of the neutralizing antibodies for the 10246, 40812TXT, 11203SD, TJ-224 and CA16-194 strains from different regions of China were 137.8, 97.8, 113.4, 64.1 and 122.3, respectively. A CVA16 vaccine dose above 25 U was also able to provide 100% cross-protection against lethal challenges with these five clinical strains in gerbils. Immunization at a one-week interval could maintain a high level of neutralizing antibody titres for at least 8 weeks. Thus, the vaccine produced by this CVA16-393 strain might be promising.


Assuntos
Enterovirus Humano A , Enterovirus , Doença de Mão, Pé e Boca , Vacinas Virais , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , Criança , Pré-Escolar , Enterovirus/genética , Enterovirus Humano A/genética , Gerbillinae , Doença de Mão, Pé e Boca/prevenção & controle , Humanos , Vacinas de Produtos Inativados
18.
Front Immunol ; 13: 939311, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36032136

RESUMO

Background: Owing to the coronavirus disease 2019 (COVID-19) pandemic and the emergency use of different types of COVID-19 vaccines, there is an urgent need to consider the effectiveness and persistence of different COVID-19 vaccines. Methods: We investigated the immunogenicity of CoronaVac and Covilo, two inactivated vaccines against COVID-19 that each contain inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The levels of neutralizing antibodies to live SARS-CoV-2 and the inhibition rates of neutralizing antibodies to pseudovirus, as well as the immunoglobulin (Ig)G and IgM responses towards the spike (S) and nucleocapsid (N) protein of SARS-CoV-2 at 180 days after two-dose vaccination were detected. Results: The CoronaVac and Covilo vaccines induced similar antibody responses. Regarding neutralizing antibodies to live SARS-CoV-2, 77.9% of the CoronaVac vaccine recipients and 78.3% of the Covilo vaccine recipients (aged 18-59 years) seroconverted by 28 days after the second vaccine dose. Regarding SARS-CoV-2-specific antibodies, 97.1% of the CoronaVac vaccine recipients and 95.7% of the Covilo vaccine recipients seroconverted by 28 days after the second vaccine dose. The inhibition rates of neutralizing antibody against a pseudovirus of the SARS-CoV-2 Delta variant were significantly lower compared with those against a pseudovirus of wildtype SARS-CoV-2. Associated with participant characteristics and antibody levels, persons in the older age group and with basic disease, especially a chronic respiratory disease, tended to have lower anti-SARS-CoV-2 antibody seroconversion rates. Conclusion: Antibodies that were elicited by these two inactivated COVID-19 vaccines appeared to wane following their peak after the second vaccine dose, but they persisted at detectable levels through 6 months after the second vaccine dose, and the effectiveness of these antibodies against the Delta variant of SARS-CoV-2 was lower than their effectiveness against wildtype SARS-CoV-2, which suggests that attention must be paid to the protective effectiveness, and its persistence, of COVID-19 vaccines on SARS-CoV-2 variants.


Assuntos
COVID-19 , Vacinas Virais , Idoso , Anticorpos Neutralizantes , Anticorpos Antivirais , Atenção , Vacinas contra COVID-19 , Estudos de Coortes , Humanos , Imunoglobulina G , SARS-CoV-2
19.
Front Microbiol ; 13: 1079764, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36699595

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a novel coronavirus that caused a global outbreak of coronavirus disease 2019 (COVID-19) pandemic. To elucidate the mechanism of SARS-CoV-2 replication and immunogenicity, we performed a comparative transcriptome profile of mRNA and long non-coding RNAs (lncRNAs) in human lung epithelial cells infected with the SARS-CoV-2 wild-type strain (8X) and the variant with a 12-bp deletion in the E gene (F8). In total, 3,966 differentially expressed genes (DEGs) and 110 differentially expressed lncRNA (DE-lncRNA) candidates were identified. Of these, 94 DEGs and 32 DE-lncRNAs were found between samples infected with F8 and 8X. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyzes revealed that pathways such as the TNF signaling pathway and viral protein interaction with cytokine and cytokine receptor were involved. Furthermore, we constructed a lncRNA-protein-coding gene co-expression interaction network. The KEGG analysis of the co-expressed genes showed that these differentially expressed lncRNAs were enriched in pathways related to the immune response, which might explain the different replication and immunogenicity properties of the 8X and F8 strains. These results provide a useful resource for studying the pathogenesis of SARS-CoV-2 variants.

20.
RSC Adv ; 11(25): 15410-15415, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35424061

RESUMO

Cost-effective valorization of biomass into advanced carbon remains a challenge. Here we reported a facile and ultrafast laser writing technique to convert biomass into porous graphene for electrochemical sensing. Laser-induced graphene (LIG) was synthesized from a fully biomass-based film composed of kraft lignin (KL) and cellulose nanofibers (CNFs). The LIG-based electrode was applied to detect dopamine using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques. Dopamine with a concentration ranging from 5 to 40 µM was detected linearly, with a sensitivity of 4.39 µA µM-1 cm-2. Our study eliminated the use of synthetic polymer for lignin-based film formation. It demonstrated the feasibility of using the film fully composed of biomass for LIG formation. Furthermore, derived LIG electrodes were shown to have high electrochemical sensing performance.

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