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1.
Small ; 20(25): e2309582, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38225695

RESUMO

Electrocatalysis is considered to be an effective method to solve the sluggish kinetics of lithium-sulfur batteries. However, a single catalyst cannot simultaneously catalyze multi-step sulfur reductions. And once the catalyst surface is covered by the initially deposited solid products, the subsequent catalytic activity will significantly deteriorate. Here, microporous ZIF-67 and its derivative nano-metallic Co0 are used as dual-catalyst aiming to address these drawbacks. The dual catalytic center effectively cooperates the adsorption and electron transfer for multi-steps of sulfur reductions, transforming the potential-limited step (Li2S4→Li2S2/Li2S) into a thermodynamic spontaneous reaction. ZIF-67 first adsorbs soluble Li2S4 to form a coordination structure of ZIF-Li2S4. Then nano-metallic Co0 attracts uncoordinated S atoms in ZIF-Li2S4 and facilitates the breaking of S-S bonds to form transient reductive ZIF-Li2S2 and Co-S2 via. spontaneous electron transfer. These intermediates facilitate continuous conversion to Li2S with reduced formation energy, which is beneficial to the regeneration of the catalyst. As a result, the cathode with ZIF@CNTs/Co@CNFs synergetic catalyst achieves initial areal capacity of 4.7 mAh cm-2 and maintains 3.5 mAh cm-2 at low electrolyte/sulfur ratio (E/S) of 5 µL mg-1. This study provides valuable guidance for improving the electrochemical performance of lithium-sulfur batteries through catalyst synergistic strategies for multi-step reactions.

2.
Emerg Infect Dis ; 28(7): 1332-1344, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35476714

RESUMO

The recent rise in the frequency of influenza A(H5N6) infections in China has raised serious concerns about whether the risk for human infection has increased. We surveyed epidemiologic, clinical, and genetic data of human infections with A(H5N6) viruses. Severe disease occurred in 93.8% of cases, and the fatality rate was 55.4%. Median patient age was 51 years. Most H5N6 hemagglutinin (HA) genes in human isolates in 2021 originated from subclade 2.3.4.4b; we estimated the time to most recent common ancestor as June 16, 2020. A total of 13 genotypes with HA genes from multiple subclades in clade 2.3.4.4 were identified in human isolates. Of note, 4 new genotypes detected in 2021 were the major causes of increased H5N6 virus infections. Mammalian-adapted mutations were found in HA and internal genes. Although we found no evidence of human-to-human transmission, continuous evolution of H5N6 viruses may increase the risk for human infections.


Assuntos
Vírus da Influenza A , Influenza Aviária , Influenza Humana , Animais , China/epidemiologia , Humanos , Mamíferos , Pessoa de Meia-Idade , Filogenia , Vírus Reordenados/genética
3.
J Integr Neurosci ; 21(1): 4, 2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35164440

RESUMO

Functional connectivity of the primary visual cortex was explored with resting functional magnetic resonance imaging among adults with strabismus and amblyopia and healthy controls. We used the two-sample test and receiver operating characteristic curves to investigate the differences in mean functional connectivity values between the groups with strabismus and amblyopia and healthy controls. Compared with healthy controls, functional connectivity values in the left Brodmann areas 17, including bilateral lingual/angular gyri, were reduced in groups with strabismus and amblyopia. Moreover, functional connectivity values in the right Brodmann area 17, including left cuneus, right inferior occipital gyrus, and left inferior parietal lobule, were reduced in adults with strabismus and amblyopia. Our findings indicate that functional connectivity abnormalities exist between the primary visual cortex and other regions. This may be the basis of the pathological mechanism of visual dysfunction and stereovision disorders in adults with strabismus and amblyopia.


Assuntos
Ambliopia/fisiopatologia , Conectoma , Córtex Visual Primário/fisiopatologia , Estrabismo/fisiopatologia , Adulto , Ambliopia/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Córtex Visual Primário/diagnóstico por imagem , Estrabismo/diagnóstico por imagem , Adulto Jovem
4.
Virus Genes ; 57(2): 164-171, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33606171

RESUMO

Influenza vaccines represent the most effective preventive strategy to control influenza virus infections; however, adaptive mutations frequently occur in the hemagglutinin (HA) glycoprotein during the preparation of candidate vaccine virus and production of vaccine in embryonated eggs. In our previous study, we constructed candidate vaccine virus (HA-R) to match the highly pathogenic avian influenza H7N9 viruses A/Guangdong/17SF003/2016 as part of a pandemic preparedness program. However, mixed amino acids (R, G, and I) were presented at position 220 (H3 numbering) in HA during passage in embryonated eggs. The residue at position 220 is located close to the receptor-binding site and the biological characteristics of this site remain to be elucidated. Therefore, in this study, using reverse genetics, we constructed two viruses carrying the single substitution in position 220 of HA (HA-G and HA-I) and evaluated the biological effects of substitution (R with G/I) on receptor binding, neuraminidase (NA) activity, growth characteristics, genetic stability, and antigenicity. The results revealed both mutant viruses exhibited lower HA binding affinities to two receptor types (sialic acid in alpha2,3- and alpha2,6-linkage to galactose, P < 0.001) and significant better growth characteristics compared to HA-R in two cells. Moreover, under similar NA enzymatic activity, the two mutant viruses eluted more easily from agglutinated erythrocytes than HA-R. Collectively, these results implied the balance of HA and NA in mutant viruses was a stronger determinant of viral growth than the individual amino acid in the HA position 220 in HA-R without strong binding between HA and sialylated receptors. Importantly, both the substitutions conferred altered antigenicity to the mutant viruses. In conclusion, amino acid substitutions at position 220 can substantially influence viral biological properties.


Assuntos
Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Subtipo H7N9 do Vírus da Influenza A/genética , Vacinas contra Influenza/genética , Substituição de Aminoácidos , Animais , Cães , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Subtipo H7N9 do Vírus da Influenza A/imunologia , Vacinas contra Influenza/química , Vacinas contra Influenza/imunologia , Células Madin Darby de Rim Canino , Mutagênese , Ácido N-Acetilneuramínico/metabolismo , Neuraminidase/metabolismo , Vírus Reordenados/genética , Vírus Reordenados/imunologia , Genética Reversa
5.
Nanomedicine ; 32: 102339, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33227538

RESUMO

MicroRNA (miRNA) has emerged as a promising genetic marker for cancer diagnosis and therapy because its expression level is closely related to the progression of malignant diseases. Herein, a label-free and selective fluorescence platform was proposed for miRNA based on light-up "G-quadruplex nanostring" via duplex-specific nuclease (DSN) mediated tandem rolling circle amplification (RCA). First, a long DNA generated from upstream RCA was designed with the antisense sequences for miR-21 and downstream RCA primer. Upon recognizing miR-21, the resulting DNA-RNA permitted DSN digestion and triggered downstream two-way RCA, and generation of abundant "G-quadruplex nanostring" binding with ZnPPIX for label-free fluorescent responses. In our strategy, the strong preference of DSN for perfectly matched DNA/RNA ensures its excellent selectivity. The developed method generated wide linear response with LOD of 1.019 fM. Additionally, the miR-21 levels in cell extracts have been evaluated, revealing the utility of this tool for biomedical research and clinical diagnosis.


Assuntos
Endonucleases/metabolismo , Quadruplex G , MicroRNAs/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , Estudos de Viabilidade , Células HeLa , Humanos , MicroRNAs/metabolismo , Espectrometria de Fluorescência
6.
Analyst ; 145(22): 7448, 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-32966362

RESUMO

Correction for 'A facile deoxyuridine/biotin-modified molecular beacon for simultaneous detection of proteins and nucleic acids via a label-free and background-eliminated fluorescence assay' by Fei Yin, et al., Analyst, 2019, 144, 5504-5510, DOI: 10.1039/C9AN01016E.

7.
Analyst ; 144(18): 5504-5510, 2019 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-31389925

RESUMO

Simultaneous detection of different types of cancer biomarkers (nucleic acids and proteins) could facilitate early diagnosis of cancer and clinical treatment. Herein, a simultaneous detection platform of proteins and nucleic acids has been developed using a single substrate probe combining a label-free and background-eliminated fluorescence assay. Telomerase and telomerase RNA (TR) were chosen as the models. The molecular beacon (dU-BIO-HP) that contains deoxyuridine/biotin in its side arm, a TR recognition sequence in the loop and a telomerase substrate primer at the stem end was ingeniously designed. In the presence of telomerase, the stem of dU-BIO-HP is elongated by the addition of telomere repeats complementary to the assistant DNA. Furthermore, the formed dsDNA performed as engaging primers to initiate a SDA reaction, generating abundant G-quadruplex monomers. Similarly, on TR, the hybridization between TR and dU-BIO-HP can open its stem, triggering another SDA reaction, producing abundant short ssDNAs. With the G-quadruplex binding with ZnPPIX and ssDNA binding with SG for specific fluorescence responses, the label-free multiple detection can be achieved. In our strategy, the deoxyuridine of dU-BIO-HP acts as a barrier to block the DNA extension due to its strong inhibitory effects on DNA polymerase activity and to make sure that the two SDA reactions occurred independently. The biotin of dU-BIO-HP enables the reduction of the background from the binding between SG, ZnPPIX and dU-BIO-HP through streptavidin-biotin interaction. This method showed an excellent sensitivity with telomerase and TR detection limit of 2.18 HeLa cells per mL and 0.16 × 10-12 M, respectively. Furthermore, the telomerase and TR in different cell lines have been evaluated as powerful tools for biomedical research and clinical diagnosis.


Assuntos
Biomarcadores Tumorais/análise , RNA/análise , Telomerase/análise , Biotina/química , Linhagem Celular Tumoral , Sondas de DNA/química , Sondas de DNA/genética , Desoxiuridina/química , Ensaios Enzimáticos/métodos , Corantes Fluorescentes/química , Humanos , Limite de Detecção , Técnicas de Amplificação de Ácido Nucleico , Hibridização de Ácido Nucleico , Compostos Orgânicos/química , RNA/genética , Espectrometria de Fluorescência , Telomerase/genética
8.
Nature ; 499(7459): 500-3, 2013 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-23823727

RESUMO

Human infection associated with a novel reassortant avian influenza H7N9 virus has recently been identified in China. A total of 132 confirmed cases and 39 deaths have been reported. Most patients presented with severe pneumonia and acute respiratory distress syndrome. Although the first epidemic has subsided, the presence of a natural reservoir and the disease severity highlight the need to evaluate its risk on human public health and to understand the possible pathogenesis mechanism. Here we show that the emerging H7N9 avian influenza virus poses a potentially high risk to humans. We discover that the H7N9 virus can bind to both avian-type (α2,3-linked sialic acid) and human-type (α2,6-linked sialic acid) receptors. It can invade epithelial cells in the human lower respiratory tract and type II pneumonocytes in alveoli, and replicated efficiently in ex vivo lung and trachea explant culture and several mammalian cell lines. In acute serum samples of H7N9-infected patients, increased levels of the chemokines and cytokines IP-10, MIG, MIP-1ß, MCP-1, IL-6, IL-8 and IFN-α were detected. We note that the human population is naive to the H7N9 virus, and current seasonal vaccination could not provide protection.


Assuntos
Vírus da Influenza A/fisiologia , Influenza Aviária/virologia , Receptores Virais/metabolismo , Animais , Anticorpos Antivirais/imunologia , Aves/virologia , Brônquios/citologia , Brônquios/metabolismo , Brônquios/virologia , Linhagem Celular , Quimiocinas/sangue , China , Reações Cruzadas/imunologia , Células Epiteliais/virologia , Especificidade de Hospedeiro , Humanos , Técnicas In Vitro , Virus da Influenza A Subtipo H5N1/imunologia , Virus da Influenza A Subtipo H5N1/fisiologia , Vírus da Influenza A/imunologia , Vírus da Influenza A/patogenicidade , Vacinas contra Influenza/imunologia , Influenza Aviária/transmissão , Influenza Humana/sangue , Influenza Humana/imunologia , Influenza Humana/virologia , Pulmão/virologia , Ácido N-Acetilneuramínico/análogos & derivados , Ácido N-Acetilneuramínico/química , Ácido N-Acetilneuramínico/metabolismo , Especificidade de Órgãos , Alvéolos Pulmonares/citologia , Alvéolos Pulmonares/metabolismo , Alvéolos Pulmonares/virologia , Receptores Virais/química , Traqueia/virologia , Replicação Viral , Zoonoses/transmissão , Zoonoses/virologia
9.
J Virol ; 90(12): 5561-5573, 2016 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-27030268

RESUMO

UNLABELLED: Due to enzootic infections in poultry and persistent human infections in China, influenza A (H7N9) virus has remained a public health threat. The Yangtze River Delta region, which is located in eastern China, is well recognized as the original source for H7N9 outbreaks. Based on the evolutionary analysis of H7N9 viruses from all three outbreak waves since 2013, we identified the Pearl River Delta region as an additional H7N9 outbreak source. H7N9 viruses are repeatedly introduced from these two sources to the other areas, and the persistent circulation of H7N9 viruses occurs in poultry, causing continuous outbreak waves. Poultry movements may contribute to the geographic expansion of the virus. In addition, the AnH1 genotype, which was predominant during wave 1, was replaced by JS537, JS18828, and AnH1887 genotypes during waves 2 and 3. The establishment of a new source and the continuous evolution of the virus hamper the elimination of H7N9 viruses, thus posing a long-term threat of H7N9 infection in humans. Therefore, both surveillance of H7N9 viruses in humans and poultry and supervision of poultry movements should be strengthened. IMPORTANCE: Since its occurrence in humans in eastern China in spring 2013, the avian H7N9 viruses have been demonstrating the continuing pandemic threat posed by the current influenza ecosystem in China. As the viruses are silently circulated in poultry, with potentially severe outcomes in humans, H7N9 virus activity in humans in China is very important to understand. In this study, we identified a newly emerged H7N9 outbreak source in the Pearl River Delta region. Both sources in the Yangtze River Delta region and the Pearl River Delta region have been established and found to be responsible for the H7N9 outbreaks in mainland China.


Assuntos
Surtos de Doenças , Subtipo H7N9 do Vírus da Influenza A/isolamento & purificação , Influenza Aviária/epidemiologia , Influenza Humana/epidemiologia , Influenza Humana/virologia , Animais , China/epidemiologia , Evolução Molecular , Genes Virais , Genótipo , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Humanos , Subtipo H7N9 do Vírus da Influenza A/classificação , Subtipo H7N9 do Vírus da Influenza A/genética , Influenza Aviária/virologia , Neuraminidase/genética , Filogenia , Aves Domésticas , Vírus Reordenados , Rios
10.
MMWR Morb Mortal Wkly Rep ; 66(35): 928-932, 2017 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-28880856

RESUMO

Among all influenza viruses assessed using CDC's Influenza Risk Assessment Tool (IRAT), the Asian lineage avian influenza A(H7N9) virus (Asian H7N9), first reported in China in March 2013,* is ranked as the influenza virus with the highest potential pandemic risk (1). During October 1, 2016-August 7, 2017, the National Health and Family Planning Commission of China; CDC, Taiwan; the Hong Kong Centre for Health Protection; and the Macao CDC reported 759 human infections with Asian H7N9 viruses, including 281 deaths, to the World Health Organization (WHO), making this the largest of the five epidemics of Asian H7N9 infections that have occurred since 2013 (Figure 1). This report summarizes new viral and epidemiologic features identified during the fifth epidemic of Asian H7N9 in China and summarizes ongoing measures to enhance pandemic preparedness. Infections in humans and poultry were reported from most areas of China, including provinces bordering other countries, indicating extensive, ongoing geographic spread. The risk to the general public is very low and most human infections were, and continue to be, associated with poultry exposure, especially at live bird markets in mainland China. Throughout the first four epidemics of Asian H7N9 infections, only low pathogenic avian influenza (LPAI) viruses were detected among human, poultry, and environmental specimens and samples. During the fifth epidemic, mutations were detected among some Asian H7N9 viruses, identifying the emergence of high pathogenic avian influenza (HPAI) viruses as well as viruses with reduced susceptibility to influenza antiviral medications recommended for treatment. Furthermore, the fifth-epidemic viruses diverged genetically into two separate lineages (Pearl River Delta lineage and Yangtze River Delta lineage), with Yangtze River Delta lineage viruses emerging as antigenically different compared with those from earlier epidemics. Because of its pandemic potential, candidate vaccine viruses (CVV) were produced in 2013 that have been used to make vaccines against Asian H7N9 viruses circulating at that time. CDC is working with partners to enhance surveillance for Asian H7N9 viruses in humans and poultry, to improve laboratory capability to detect and characterize H7N9 viruses, and to develop, test and distribute new CVV that could be used for vaccine production if a vaccine is needed.


Assuntos
Epidemias/estatística & dados numéricos , Subtipo H7N9 do Vírus da Influenza A/isolamento & purificação , Influenza Humana/epidemiologia , Influenza Humana/virologia , Vigilância da População , Animais , China/epidemiologia , Humanos , Influenza Aviária/transmissão , Influenza Aviária/virologia , Pandemias/prevenção & controle , Aves Domésticas
11.
Euro Surveill ; 22(19)2017 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-28537546

RESUMO

With no or low virulence in poultry, avian influenza A(H7N9) virus has caused severe infections in humans. In the current fifth epidemic wave, a highly pathogenic avian influenza (HPAI) H7N9 virus emerged. The insertion of four amino acids (KRTA) at the haemagglutinin (HA) cleavage site enabled trypsin-independent infectivity of this virus. Although maintaining dual receptor-binding preference, its HA antigenicity was distinct from low-pathogenic avian influenza A(H7N9). The neuraminidase substitution R292K conferred a multidrug resistance phenotype.


Assuntos
Surtos de Doenças , Subtipo H7N9 do Vírus da Influenza A/genética , Subtipo H7N9 do Vírus da Influenza A/patogenicidade , Influenza Humana/epidemiologia , Influenza Humana/virologia , Neuraminidase/genética , Virulência/genética , Animais , Antivirais/farmacologia , China/epidemiologia , Feminino , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Humanos , Subtipo H7N9 do Vírus da Influenza A/efeitos dos fármacos , Subtipo H7N9 do Vírus da Influenza A/isolamento & purificação , Influenza Aviária/virologia , Neuraminidase/metabolismo , Aves Domésticas , Carga Viral
12.
J Mater Sci Mater Med ; 25(12): 2743-56, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25085242

RESUMO

An amine-functionalized succinyl chitosan and an oxidized dextran were synthesized and mixed in aqueous solution to form an in situ chitosan/dextran injectable, surgical hydrogel for adhesion prevention. Rheological characterization showed that the rate of gelation and moduli were tunable based on amine and aldehyde levels, as well as polymer concentrations. The CD hydrogels have been shown to be effective post-operative aids in prevention of adhesions in ear, nose, and throat surgeries and abdominal surgeries in vivo. In vitro biocompatibility testing was performed on CD hydrogels containing one of two oxidized dextrans, an 80 % oxidized (CD-100) or 25 % (CD-25) oxidized dextran. However, the CD-100 hydrogel showed moderate cytotoxicity in vitro to Vero cells. SC component of the CD hydrogel, however, showed no cytotoxic effect. In order to increase the biocompatibility of the hydrogel, a lower aldehyde level hydrogel was developed. CD-25 was found to be non-cytotoxic to L929 fibroblasts. The in vivo pro-inflammatory response of the CD-25 hydrogel, after intraperitoneal injection in BALB/c mice, was also determined by measuring serum TNF-α levels and by histological analysis of tissues. TNF-α levels were similar in mice injected with CD-25 hydrogel as compared to the negative saline injected control; and were significantly different (P < 0.05) as compared to the positive, lipopolysaccharide, injected control. Histological examination revealed no inflammation seen in CD hydrogel injected mice. The results of these in vitro and in vivo studies demonstrate the biocompatibility of the CD hydrogel as a post-operative aid for adhesion prevention.


Assuntos
Curativos Hidrocoloides , Materiais Biocompatíveis/síntese química , Sobrevivência Celular/fisiologia , Quitosana/química , Dextranos/química , Hidrogéis/química , Aderências Teciduais/prevenção & controle , Animais , Materiais Biocompatíveis/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Quitosana/farmacologia , Chlorocebus aethiops , Dextranos/farmacologia , Módulo de Elasticidade , Desenho de Equipamento , Análise de Falha de Equipamento , Dureza , Humanos , Hidrogéis/farmacologia , Teste de Materiais , Células Vero
13.
Front Nutr ; 11: 1349162, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38660064

RESUMO

Pectin was extracted from Actinidia arguta Sieb. et Zucc (A.arguta) using the ultrasound-assisted acid method and the single acid method. The physicochemical properties, structure, and antioxidant properties of two different pectins were investigated. The results showed that the extraction yield of the ultrasound-assisted acid method is higher than that of the single acid method. The molecular structure of A. arguta pectin extracted by the ultrasound-assisted acid method belongs to a mixed structure of RG-I and HG-type domains. Through structural feature analysis, the ultrasound-assisted extraction pectin (UAP) has a more branched structure than the single acid-extracted pectin (SAP). The SAP has a higher degree of esterification than the UAP. The physical property results show that the viscosity, solubility, and water-holding capacity of the UAP are better than those of the SAP. The antioxidant test results show that the hydroxyl radical scavenging and reducing powers of the UAP are superior to those of the SAP. This study shows the composition, physicochemical properties, and antioxidant activity of A. arguta pectin extracted by the ultrasonic-assisted extraction method to provide a theoretical basis for its application as an antioxidant and other food additives in the food industry.

14.
Biosens Bioelectron ; 260: 116455, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38824702

RESUMO

In this work, a potential-controlled electrochromic visual biosensor was developed for detecting zearalenone (ZEN) using a distance readout strategy. The sensor chip includes a square detection area and a folded signal output area created with laser etching technology. The detection area is modified with graphene oxide and ZEN aptamer, while Prussian blue (PB) is electrodeposited onto the signal output channel. When an appropriate voltage is applied, PB in the signal output area is reduced to colorless Prussian white (PW). The target ZEN molecules have the capability to release aptamers from graphene oxide (GO) surface in the detection area, resulting in a subsequent change in the potential of the visual signal output channel. This change determines the length of the channel that changes from blue to colorless, with the color change distance being proportional to the ZEN concentration. Using this distance readout strategy, ZEN detection within the range of 1 ng/mL to 300 ng/mL was achieved, with a detection limit of 0.29 ng/mL.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Grafite , Limite de Detecção , Zearalenona , Zearalenona/análise , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/instrumentação , Grafite/química , Aptâmeros de Nucleotídeos/química , Técnicas Eletroquímicas/métodos , Desenho de Equipamento , Ferrocianetos/química , Colorimetria/instrumentação , Colorimetria/métodos
15.
Emerg Microbes Infect ; : 2373314, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38922326

RESUMO

The proportion of human isolates with reduced neuraminidase inhibitors (NAIs) susceptibility in highly pathogenic avian influenza (HPAI) H7N9 virus was as high as 13%. These drug-resistant strains showed good replication capacity without serious loss of fitness. At the presence of oseltamivir, R229I substitution were found in HA1 region of the HPAI H7N9 virus before NA R292 K appeared. HPAI H7N9 or H7N9/PR8 recombinant viruses were developed to study whether HA R229I could increase the fitness of the H7N9 virus bearing NA 292 K. Replication efficiency was assessed in MDCK or A549 cells. Neuraminidase enzyme activity and receptor-binding ability were analyzed. The pathogenicity in C57 mice was evaluated. Antigenicity analysis was conducted through a two-way HI test, in which the antiserum was obtained from immunized ferrets. Transcriptomic analysis of MDCK infected with HPAI H7N9 24hpi was done. It turned out that HA R229I substitution from oseltamivir induction in HA1 region increased 1)replication ability in MDCK(P < 0.05) and A549(P < 0.05), 2)neuraminidase enzyme activity, 3)binding ability to both α2,3 and α2,6 receptor, 4)pathogenicity to mice(more weight loss; shorter mean survival day; viral titer in respiratory tract, P < 0.05; Pathological changes in pneumonia), 5) transcriptome response of MDCK, of the H7N9 virus bearing NA 292 K. Besides, HA R229I substitution changed the antigenicity of H7N9/PR8 virus (>4-fold difference of HI titer). It indicated that through the fine-tuning of the HA-NA balance, R229I increased the fitness and change the antigenicity of a H7N9 virus bearing NA 292 K. Public health attention of this mechanism needs to be drawn.

16.
Biosens Bioelectron ; 240: 115651, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37666010

RESUMO

The global spread of environmental biological pollutants, such as antibiotic-resistant bacteria and their antibiotic resistance genes (ARGs), has emerged as a critical public health concern. It is imperative to address this pressing issue due to its potential implications for public health. Herein, a DNA paperclip probe with double-quenching function of target cyclic cleavage was proposed, and an electrochemiluminescence (ECL) biosensing platform was constructed using Ti3C2 MXene in-situ reduction growth of Au NPs (TCM-Au) as a coreactant accelerator, and applied to the sensitive detection of ARGs. Thanks to the excellent catalytic performance, large surface area and Au-S affinity of TCM-Au, the ECL performance of CdS QDs have been significantly improved. By cleverly utilizing the negative charge of the paperclip nucleic acid probe and its modification group, double-quenching of the ECL signal was achieved. This innovative approach, combined with target cyclic amplification, facilitated specific and sensitive detection of the mecA gene. This biosensing platform manifested highly selective and sensitive determination of mecA genes in the range of 10 fM to 100 nM and a low detection limit of 2.7 fM. The credible detectability and anti-interference were demonstrated in Yangtze river and Aeration tank outlet, indicating its promising application toward pollution monitoring of ARGs.


Assuntos
Técnicas Biossensoriais , Poluentes Ambientais , Titânio , Antibacterianos , Resistência Microbiana a Medicamentos
17.
Clin Exp Optom ; : 1-7, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37989320

RESUMO

CLINICAL RELEVANCE: Raising children's myopia prevention awareness and behaviour tends to exhibits a protective effect against myopia among schoolchildren. BACKGROUND: To investigate the effect of an original myopia song in raising school children's awareness of healthier eye use behaviour and on myopia prevention. METHODS: In this prospective randomised control study, two groups of students from one primary schools in Jiangxi, China, were enrolled and monitored from grade 3 to grade 6 (2016-2019). The primary outcome was the change in axial length (AL) after the intervention. Secondary outcomes included changes in spherical equivalent refraction (SER), near work and outdoor time, corrected near and distant visual acuity, visual discomfort score (VDS) and accommodative lag. RESULTS: Four hundred students (193 females, 48.25%) aged 9.3 (range 8-10) years with emmetropia to moderate myopia were enrolled. Children in the myopia song group had a significantly shorter AL and less myopic refractive change than those in the control group (p = 0.04 and 0.02, respectively). Compared with the control group, children in the myopia song group spent less time on near work and more time outdoors (p = 0.04 and 0.04, respectively). At the final follow-up, the proportion of children with myopia was significantly lower in the myopia song group (30.5%) than in the control group (41%) (p = 0.03). No significant differences were found for the secondary outcomes, including corrected near and distant visual acuity, VDS and accommodative lag. CONCLUSIONS: An original myopia song performed twice daily in primary schools appeared to have a modest effect on myopia control among school-aged children by changing their lifestyles in the long term.

18.
J Biophotonics ; 16(11): e202300133, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37369631

RESUMO

OBJECTIVE: To evaluate the effect of hydroxychloroquine on conjunctival and retinal microvascular density in rheumatoid arthritis (RA) patients. METHODS: Ten healthy controls, 10 RA patients who had not been treated with hydroxychloroquine, and 10 RA patients who had been treated with chloroquine for more than 5 years were recruited. Optical coherence tomography (OCTA) was used to examine the conjunctival and superficial and deep retinal microvascular density and compared the differences in microvascular density between the three groups. RESULTS: The vascular density in RA group in superficial microvascular was significantly lower than that in control group (p < 0.001). Compared with RA group, the chloroquine group showed statistically significantly lower microvascular (p < 0.001) and deep microvascular (p = 0.018). Superficial microvascular was positively correlated with conjunctival vessel density in RA patients (r = 0.868, p = 0.0048). CONCLUSIONS: The use of chloroquine could further reduce the vascular density in the absence of statistical difference in the course of the disease.


Assuntos
Artrite Reumatoide , Hidroxicloroquina , Humanos , Hidroxicloroquina/uso terapêutico , Hidroxicloroquina/farmacologia , Vasos Retinianos/diagnóstico por imagem , Cloroquina/uso terapêutico , Cloroquina/farmacologia , Angiofluoresceinografia/métodos , Artrite Reumatoide/diagnóstico por imagem , Artrite Reumatoide/tratamento farmacológico , Tomografia de Coerência Óptica/métodos
19.
Influenza Other Respir Viruses ; 16(3): 577-584, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35037399

RESUMO

BACKGROUND: The first and only case of human infection with the avian influenza A (H7N4) virus in China emerged in 2018. The H7N4 virus was distinct from previous H7N9 viruses and raised public concerns. Therefore, developing a suitable H7N4 candidate vaccine virus (CVV) remains crucial for potential pandemic preparedness. METHODS: We constructed a reassortant virus with a (6 + 2) genome composition, then introduced the polymerase basic protein 1 (PB1) from a wild-type virus to develop a (5 + 3) reassortant virus through reverse genetics. We performed whole-genome sequencing to confirm the genome stability, assessed the growth ability in MDCK cells, and analyzed virus antigenicity using hemagglutination inhibition assays. Subsequently, the effect of homologous PB1 on polymerase activity, viral protein yield, and pathogenicity was assessed. RESULTS: The (5 + 3) virus harbouring the homologous PB1 gene exhibited significantly improved growth characteristics, higher viral protein yield, and polymerase activity than the (6 + 2) virus. After successive passage in embryonated eggs, glutamic acid (E) substituted glycine(G) at position 218 (H3 numbering) in the hemagglutinin (HA) gene of both (5 + 3) and (6 + 2) viruses. The substitution improved the growth of the (6 + 2) virus but exhibited no significant effect or alteration on the antigenicity of the (5 + 3) virus. Moreover, the (5 + 3) virus exhibited low pathogenicity in chickens and ferrets. CONCLUSION: Homologous PB1 of the H7N4 virus improves the growth ability while sustaining low pathogenicity. Collectively, the gene composition of the (5 + 3) reassortant virus is a suitable H7N4 CVV for potential pandemic preparedness.


Assuntos
Subtipo H7N9 do Vírus da Influenza A , Vacinas contra Influenza , Influenza Aviária , Vacinas , Animais , Galinhas , Furões , Humanos , Subtipo H7N9 do Vírus da Influenza A/genética , Vacinas contra Influenza/genética , Influenza Aviária/prevenção & controle , Vírus Reordenados/genética , Replicação Viral
20.
Front Hum Neurosci ; 16: 900409, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35693538

RESUMO

Purpose: To investigate spontaneous brain activity in patients with dry eye (DE) and healthy control (HC) using the fractional amplitude of low frequency fluctuation (fALFF) technique with the aim of elucidating the relationship between the clinical symptoms of DE and changes in brain function. Material and Methods: A total of 28 patients with DE and 28 matched healthy volunteers (10 males and 18 females in each group) were enrolled. Resting-state functional magnetic resonance imaging scans were performed in both groups. Then all subjects were required to complete a comprehensive Hospital Anxiety and Depression Scale (HADS). Receiver operating characteristic (ROC) curve analysis was used to evaluate the differences in fALFF values between the two groups and their diagnostic value. Linear correlations between HADS and fALFF values in different brain regions of DE patients were analyzed using the Pearson correlation coefficient. Results: Patients with DE had significantly higher fALFF values in the left calcarine sulcus (CS) than the HC group, while fALFF values in the bilateral middle frontal gyrus (MFG) and right MFG/right inferior frontal gyrus (IFG) were significantly lower in DE patients than in HC group. fALFF values had a high diagnostic value for differentiating patients with DE from the HC group (P < 0.001). Right MFG and right MFG/IFG were significantly correlated with HADS values. Conclusion: Our study found that DE mainly involved functional disorders in the brain areas of the left CS, bilateral MFG and right MFG/right IFG, which helped us to find possible clinical features of DE disease and reflected the potential pathological mechanism of DE.

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