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1.
J Am Chem Soc ; 146(6): 4242-4251, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38300828

RESUMO

Understanding the reconstruction of electrocatalysts under operational conditions is essential for studying their catalytic mechanisms and industrial applications. Herein, using spatiotemporally resolved Raman spectroscopy with CO as a probe molecule, we resolved the spontaneous reconstruction of Cu active sites during cathodic CO reduction reactions (CORRs). Quasi-in situ focused ion beam transmission electron microscopy (FIB-TEM) revealed that under prolonged electrolysis, the Cu surface can reconstruct to form nanometer-sized Cu particles with (111)/(100) facets and abundant grain boundaries, which strongly favor the formation of an inactive *CObridge binding site and deteriorate the CORR performance. A short period of anodic oxidation can efficiently remove these reconstructed nanoparticles by quick dissolution of Cu, thus providing an effective strategy to regenerate the Cu catalysts and recover their CORR performance. This study provides real-time in situ observations of Cu reconstruction and changes in the binding of key reaction intermediates, highlighting the decisive role of the local active site, rather than the macroscopic morphology, on adsorption of key reaction intermediates and thus CORR performance.

2.
Virol J ; 19(1): 203, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36457099

RESUMO

BACKGROUND: Coxsackievirus A10 (CV-A10) is a leading cause of hand, foot, and mouth disease (HFMD). It is necessary to identify neutralizing epitopes to investigate and develop an epitope-based vaccine against CV-A10. The viral protein VP1 is the immunodominant capsid protein and contains the critical neutralizing epitope. However, neutralizing epitopes within VP1 protein of CV-A10 have not been well characterized. METHODS: Bioinformatics techniques were applied to predict linear epitopes on the CV-A10 VP1 protein. The advanced structural features of epitopes were analyzed by three-dimensional (3D) modeling. The anticipated epitope peptides were synthesized and used to immunize mice as antigens. ELISA and micro-neutralization assay were used to determine the specific IgG antibody and neutralizing antibody titers. The protective efficacy of the epitope peptides in vivo was evaluated using a passive immunization/challenge assay. RESULTS: Three linear epitopes (EP3, EP4, and EP5) were predicted on CV-A10 VP1, all spatially exposed on the capsid surface, and exhibited adequate immunogenicity. However, only EP4, corresponding to residues 162-176 of VP1, demonstrated potent neutralization against CV-A10. To determine the neutralizing capacity of EP4 further, EP4 double-peptide was synthesized and injected into mice. The mean neutralizing antibody titer of the anti-EP4 double-peptide sera was 1:50.79, which provided 40% protection against lethal infection with CV-A10 in neonatal mice. In addition, sequence and advanced structural analysis revealed that EP4 was highly conserved among representative strains of CV-A10 and localized in the EF loop region of VP1, like EV-A71 SP55 or CV-A16 PEP55. CONCLUSIONS: These data demonstrate that EP4 is a specific linear neutralizing epitope on CV-A10 VP1. Its protective efficacy can be enhanced by increasing its copy number, which will be the foundation for developing a CV-A10 epitope-based vaccine.


Assuntos
Proteínas do Capsídeo , Biologia Computacional , Enterovirus , Animais , Camundongos , Anticorpos Neutralizantes , Proteínas do Capsídeo/genética , Epitopos
3.
J Am Chem Soc ; 142(27): 11829-11834, 2020 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-32574495

RESUMO

Many electrochemical processes are governed by the transfer of protons to the surface, which can be coupled with electron transfer; this electron transfer is in general non-integer and unknown a priori, but is required to hold the potential constant. In this study, we employ a combination of surface spectroscopic techniques and grand-canonical electronic-structure calculations in order to rigorously understand the thermodynamics of this process. Specifically, we explore the protonation/deprotonation of 4-mercaptobenzoic acid as a function of the applied potential. Using grand-canonical electronic-structure calculations, we directly infer the coupled electron transfer, which we find to be on the order of 0.1 electron per proton; experimentally, we also access this quantity via the potential-dependence of the pKa. We show a striking agreement between the potential-dependence of the measured pKa and that calculated with electronic-structure calculations. We further employ a simple electrostatics-based model to show that this slope can equivalently be interpreted to provide information on the degree of coupled electron transfer or the potential change at the point of the charged species.

4.
J Cardiovasc Pharmacol ; 76(1): 77-85, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32398474

RESUMO

Increasing evidence has confirmed that both long noncoding RNAs (lncRNAs) and microRNAs (miRNAs) exert key roles in the pathogenesis of myocardial infarction (MI). Previous microarray assay results revealed that lncRNA LNC_000898 expression was significantly downregulated in acute MI. However, the specific function of LNC_000898 on MI is still unclear. Our study was aimed to explore the role of LNC_000898 on cardiac MI injury and investigate its underlying mechanism. The male C57BL/6 mouse was used as cardiac MI injury animal models, and neonatal mouse ventricular cardiomyocytes (NMCMs) exposed to hypoxia were used as an in vitro model. Quantitative real-time polymerase chain reaction analysis, Western blot analysis, Tunel immunofluorescence staining assay, and cardiac echocardiography measurement were conducted to detect corresponding indicators. The results indicated that LNC_000898 expression was downregulated in marginal tissue of MI and in NMCMs exposed to hypoxia. Overexpression of LNC_000898 decreased cardiomyocyte apoptosis both in vivo and in vitro. In addition, we elaborated that LNC_000898 exerts its inhibitory effect on apoptosis after MI through the miR-375/PDK1 axis. Through miR-375 overexpression or silencing PDK1, the biological effects of LNC_000898 on hypoxia-induced NMCM injury were partially reversed. These data not only demonstrate that LNC_000898 could protect the heart against MI injury by regulating miR-375/PDK1 but also provide a new understanding to better protection of MI injury through the LNC_000898/miR-375/PDK1 axis.


Assuntos
Proteínas Quinases Dependentes de 3-Fosfoinositídeo/metabolismo , Apoptose , MicroRNAs/metabolismo , Infarto do Miocárdio/enzimologia , Miócitos Cardíacos/enzimologia , RNA Longo não Codificante/metabolismo , Proteínas Quinases Dependentes de 3-Fosfoinositídeo/genética , Animais , Hipóxia Celular , Células Cultivadas , Modelos Animais de Doenças , Fibrose , Masculino , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Infarto do Miocárdio/genética , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Miócitos Cardíacos/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Longo não Codificante/genética , Transdução de Sinais , Função Ventricular Esquerda , Remodelação Ventricular
5.
Angew Chem Int Ed Engl ; 59(35): 14942-14949, 2020 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-32394517

RESUMO

Despite recent progress in producing perovskite nanowires (NWs) for optoelectronics, it remains challenging to solution-print an array of NWs with precisely controlled position and orientation. Herein, we report a robust capillary-assisted solution printing (CASP) strategy to rapidly access aligned and highly crystalline perovskite NW arrays. The key to the CASP approach lies in the integration of capillary-directed assembly through periodic nanochannels and solution printing through the programmably moving substrate to rapidly guide the deposition of perovskite NWs. The growth kinetics of perovskite NWs was closely examined by in situ optical microscopy. Intriguingly, the as-printed perovskite NWs array exhibit excellent optical and optoelectronic properties and can be conveniently implemented for the scalable fabrication of photodetectors.

6.
Virol J ; 16(1): 98, 2019 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-31387601

RESUMO

BACKGROUND: Coxsackievirus A10 (CA10) constitutes one of the four major pathogens causing hand, foot and mouth disease in infants. Infectious clones are of great importance for studying viral gene functions and pathogenic mechanism. However, there is no report on the construction of CA10 infectious clones. METHODS: The whole genome of CA10 derived from a clinical isolate was amplified into two fragments and ligated into a linearized plasmid vector in one step by In-Fusion Cloning. The obtained CA10 cDNA clones and plasmids encoding T7 RNA polymerase were co-transfected into 293 T cells to rescue CA10 virus. The rescued virus was identified by SDS-PAGE, Western blotting and transmission electron microscopic. One-day-old ICR mice were intracerebrally inoculated with the CA10 virus and clinical symptoms were observed. Multiple tissues of moribund mice were harvested for analysis of pathogenic changes and viral distribution by using H&E staining, real-time PCR and immunohistochemical staining. RESULTS: CA10 viruses were rescued from the constructed cDNA clone and reached a maximum titer of 108.125TCID50/mL after one generation in RD cells. The virus exhibited similar physical and chemical properties to those of the parental virus. It also showed high virulence and the ability to induce death of neonatal ICR mice. Severe necrotizing myositis, intestinal villus interstitial edema and severe alveolar shrinkage were observed in infected mice. The viral antigen and the maximum amount of viral RNA were detected in limb skeletal muscles, which suggested that the limb skeletal muscles were the most likely site of viral replication. CONCLUSION: Infectious clones of CA10 were successfully constructed for the first time, which will facilitate the establishment of standardized neonatal mouse models infected with CA10 for the evaluation of vaccines and antiviral drugs, as well as preservation and sharing of model strains.


Assuntos
DNA Complementar/genética , Enterovirus/genética , Genoma Viral , Animais , Células Cultivadas , Clonagem Molecular , Infecções por Coxsackievirus/virologia , Camundongos , Camundongos Endogâmicos ICR , RNA Viral/genética , Replicação Viral
7.
Angew Chem Int Ed Engl ; 54(8): 2425-30, 2015 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-25327587

RESUMO

A Ru(3+)-mediated synthesis for the unique Pd concave nanostructures, which can directly harvest UV-to-visible light for styrene hydrogenation, is described. The catalytic efficiency under 100 mW cm(-2) full-spectrum irradiation at room temperature turns out to be comparable to that of thermally (70 °C) driven reactions. The yields obtained with other Pd nanocrystals, such as nanocubes and octahedrons, are lower. The nanostructures reported here have sufficient plasmonic cross-sections for light harvesting in a broad spectral range owing to the reduced shape symmetry, which increases the solution temperature for the reaction by the photothermal effect. They possess a large quantity of atoms at corners and edges where local heat is more efficiently generated, thus providing active sites for the reaction. Taken together, these factors drastically enhance the hydrogenation reaction by light illumination.

8.
Arch Virol ; 159(11): 3043-51, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25064513

RESUMO

Both porcine reproductive and respiratory syndrome and swine influenza are acute, highly contagious swine diseases. These diseases pose severe threats for the swine industry and cause heavy economic losses worldwide. In this study, we have developed a chimeric virus-like particle (VLP) vaccine candidate for porcine reproductive and respiratory syndrome virus (PRRSV) and H3N2 influenza virus and investigated its immunogenicity in mice. The HA and M1 proteins from the H3N2 influenza virus and the PRRSV GP5 protein fused to the cytoplasmic and transmembrane domains of the NA protein were both incorporated into the chimeric VLPs. Analysis of the immune responses showed that the chimeric VLPs elicited serum antibodies specific for both PRRSV GP5 and the H3N2 HA protein, and they stimulated cellular immune responses compared to the responses to equivalent amounts of inactivated viruses. Taken together, the results suggested that the chimeric VLP vaccine represents a potential strategy for the development of a safe and effective vaccine to control PRRSV and H3N2 influenza virus.


Assuntos
Hemaglutininas Virais/imunologia , Vírus da Influenza A Subtipo H3N2/imunologia , Infecções por Orthomyxoviridae/veterinária , Síndrome Respiratória e Reprodutiva Suína/prevenção & controle , Vírus da Síndrome Respiratória e Reprodutiva Suína/imunologia , Doenças dos Suínos/prevenção & controle , Proteínas do Envelope Viral/imunologia , Proteínas da Matriz Viral/imunologia , Animais , Anticorpos Antivirais/imunologia , Feminino , Hemaglutininas Virais/administração & dosagem , Hemaglutininas Virais/genética , Vírus da Influenza A Subtipo H3N2/genética , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Infecções por Orthomyxoviridae/virologia , Síndrome Respiratória e Reprodutiva Suína/imunologia , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Suínos , Doenças dos Suínos/imunologia , Doenças dos Suínos/virologia , Proteínas do Envelope Viral/administração & dosagem , Proteínas do Envelope Viral/genética , Proteínas da Matriz Viral/administração & dosagem , Proteínas da Matriz Viral/genética , Vacinas Virais/administração & dosagem , Vacinas Virais/genética , Vacinas Virais/imunologia
9.
Virus Genes ; 48(2): 273-82, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24272698

RESUMO

Influenza A H3N2 virus as the cause of 1968 pandemic has since been circulating in human and swine. Our earlier study has shown that mutations of one or two cysteines in the transmembrane domain of H3 hemagglutinin (HA) affected the thermal stability and fusion activity of recombinant HA proteins. Here, we report the successful generation of three recombinant H3N2 mutant viruses (C540S, C544L, and 2C/SL) with mutations of one or two transmembrane cysteines of HA in the background of A/swine/Guangdong/01/98 [H3N2] using reverse genetics, indicating that the mutated cysteines were not essential for virus assembly and growth. Further characterization revealed that recombinant H3N2 mutant viruses exhibited larger plaque sizes, increased growth rate in cells, enhanced fusion activity, reduced thermal and acidic resistances, and increased virulence in embryonated eggs. These results demonstrated that the transmembrane cysteines (C540 and C544) in H3 HA have profound effects on the virological features of H3N2 viruses.


Assuntos
Cisteína/genética , Vírus da Influenza A Subtipo H3N2/genética , Mutação , Recombinação Genética , Animais , Sequência de Bases , Células Cultivadas , Primers do DNA , Cães , Humanos
10.
Virus Genes ; 48(2): 304-11, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24297311

RESUMO

The hemagglutinin (HA) protein as the predominant antigen, executes receptor binding and membrane fusion, which critically influence the virological characteristics of influenza viruses. The literature contained scattered data showing reduction-sensitive HA oligomers when HA proteins were analyzed under non-reducing conditions. However, whether the reduction-sensitive HA oligomers are inter-monomer disulfide-bonded has not been studied. Here, we showed: (1) the detection of ß-mercaptoethanol-sensitive H3 HA oligomers was not affected by the treatment of cells with iodoacetamide prior to cell solubilization; (2) H3 HA oligomers were present on cell surfaces; (3) H3 HA oligomers had higher density than monomers; and (4) mutation of all the five C-terminal cysteines completely abolished the formation of H3 HA oligomers. Furthermore, mutant HAs with mutations of TM cysteines, CT cysteines or all five cysteines had decreased thermal stability but increased fusion activity in comparison with wildtype HA. In conclusion, this study has presented enough evidence for the existence of inter-monomer S-S H3 HA oligomers formed by five C-terminal cysteines, and suggested that all five C-terminal cysteines exerted opposite effects on HA thermal stability and fusion activity.


Assuntos
Dissulfetos/metabolismo , Hemaglutininas/metabolismo , Insetos/citologia , Animais , Linhagem Celular , Chlorocebus aethiops , Humanos , Mercaptoetanol/administração & dosagem , Mercaptoetanol/química
11.
Pharm Biol ; 52(9): 1196-203, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25116077

RESUMO

CONTEXT: Atorvastatin is a member of the drug class known as statins, which is used for lowering blood cholesterol. OBJECTIVE: The present study investigates the effect and mechanism of atorvastatin on neointimal hyperplasia after carotid artery injury (CAI) of rat. MATERIALS AND METHODS: Fifty male rats were randomly divided into four groups: control group, sham-operated group, model group, and atorvastatin treatment group. The treatment group was fed with atorvastatin (10 mg/kg) with gastro-gavage at 5 p.m. every day for 28 d after surgery. The control group, model group, and sham-operated group were fed with the same volume of distilled water instead. The proliferations of intimal and medial layers were evaluated by hematoxylin & eosin (H&E) staining. The apoptosis of vascular smooth muscle cells (VSMCs) was determined by terminal deoxynucleotidyl transferased UTP nick end labeling (TUNEL) staining. Plasma concentrations of survivin and sFas were detected by enzyme-linked immunosorbent assay (ELISA). RESULTS: Atorvastatin reduced neointimal formation and increased apoptosis of VSMCs in neointima. VSMCs apoptosis emerged at 3 d (8.42 ± 0.449 µm) and the intimal proliferation peaked by the end of 14 d (41.58 ± 1.64 µm). The plasma levels of survivin and sFas were gradually increased with the neointimal hyperplasia and increasingly decreased after atorvastatin treatment. The plasma levels of survivin and sFas in rats were elevated at 3 d (464.80 ± 105.27 pg/ml and 3256.00 ± 478.20 pg/ml, respectively), reached the peak of survivin at 14 d (1089.20 ± 232.32 pg/ml) and sFas at 7 d (4362.00 ± 639.92 pg/ml) and decreased at 28 d (562.00 ± 90.11 pg/ml and 2148.00 ± 257.14 pg/ml, respectively) in the model group. Compared with the model group, the atorvastatin treatment group has significantly less neointimal hyperplasia and more apoptosis of VSMCs. CONCLUSIONS: Atorvastatin can inhibit neointimal hyperplasia and promote SMCs apoptosis in neointimal layers, which may be mainly associated with down-regulation of survivin and Fas expression after CAI of rat.


Assuntos
Lesões das Artérias Carótidas/tratamento farmacológico , Ácidos Heptanoicos/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Neointima/prevenção & controle , Pirróis/farmacologia , Animais , Apoptose/efeitos dos fármacos , Atorvastatina , Lesões das Artérias Carótidas/fisiopatologia , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Hiperplasia/prevenção & controle , Marcação In Situ das Extremidades Cortadas , Masculino , Proteínas Associadas aos Microtúbulos/sangue , Proteínas Associadas aos Microtúbulos/genética , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Ratos , Survivina , Receptor fas/sangue , Receptor fas/genética
12.
Zhonghua Xin Xue Guan Bing Za Zhi ; 42(1): 48-52, 2014 Jan.
Artigo em Zh | MEDLINE | ID: mdl-24680270

RESUMO

OBJECTIVE: This study investigated the effect of catheter-based renal sympathetic denervation (RDN) in pigs with rapid pacing induced heart failure. METHODS: Heart failure was induced by rapid right ventricular pacing in 12 pigs and pigs were randomly divided into RDN group (n = 6): pacing+RDN at 7 days post pacing; control group (n = 6): pacing only. Echocardiography examination (LVEF, LVEDD and LVESD) was performed before pacing and at 1 and 2 weeks post pacing. Serum biochemical markers including renin, aldosterone and creatinine were also measured at baseline, 1 and 2 weeks after pacing. Repeated renal artery angiography was performed at 1 week after RDN. All pigs were sacrificed to examine the heart and renal pathology and renal artery sympathetic nerve staining at 2 weeks post pacing. RESULTS: LVEF decreased 1 week after rapid pacing from (60.5 ± 6.0)% to (35.3 ± 9.8)%. LVEF was significantly higher [(42.8 ± 5.9) % vs. (33.4 ± 9.7)%, P = 0.001 8] while LVESD was significantly lower [(28.4 ± 3.7) mm vs. (33.0 ± 2.0) mm, P = 0.001 6] in the RDN group than in the control group at 2 weeks post pacing. At 2 weeks after pacing, plasma concentrations of renin and aldosterone were significantly lower in RDN group compared to the control group (all P < 0.05) . Kidney function and blood pressure were comparable between the two groups at 2 weeks post pacing. There were no signs of renal damages such as renal artery stenosis, dissection and thrombus in all pigs after 2 weeks pacing. Sympathetic neurons of adventitia were injured in RND group. CONCLUSION: RDN could significantly improve cardiac function and attenuate left ventricular remodeling via inhibiting renin-angiotensin-aldosterone system in this pacing induced pig heart failure model.


Assuntos
Ablação por Cateter/métodos , Insuficiência Cardíaca/cirurgia , Simpatectomia/métodos , Animais , Estimulação Cardíaca Artificial/efeitos adversos , Modelos Animais de Doenças , Feminino , Insuficiência Cardíaca/etiologia , Rim/inervação , Masculino , Suínos
13.
Vaccine ; 42(21): 126108, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39048466

RESUMO

BACKGROUND: Currently, there is limited understanding of the specific humoral immune response in BA.5-infected hemodialysis patients (BA.5-CHDPs) with previous COVID-19 vaccination. Additionally, the relevant risk factors for reinfection with XBB variants in BA.5-CHDPs have yet to be elucidated. METHOD: A total of 178 BA.5-CHDPs were enrolled in this study among 53 patients who had previous vaccination. To compare hemodialysis patients in both unvaccinated and vaccinated for their immune response to the BA.5 subtype infection, we assessed serum levels of anti-ancestral-S1-IgG, anti-BA.5-receptor binding domain (RBD)-IgG, and anti-XBB.1.16-RBD-IgG using enzyme-linked immunosorbent assay, the neutralizing antibody titer against BA.5 and XBB.1.16 was determined using pseudovirus neutralization assays. Univariate and multivariate binary logistic regression analyses were conducted to identify factors associated with severe infection, the magnitude of specific humoral immunity and susceptibility to XBB variants reinfection. RESULT: Our findings indicate that BA.5-CHDPs with full or booster vaccinations have higher levels of anti-ancestral-S1-IgG than unvaccinated individuals. However, levels of anti-BA.5-RBD-IgG and anti-XBB.1.16-RBD-IgG are much lower. Booster-vaccinated BA.5-CHDPs have significantly higher levels of BA.5 and XBB.1.16 specific antibodies and neutralizing antibodies than unvaccinated patients. Low globulin levels and shorter hemodialysis duration are independent risk factors for XBB reinfection in BA.5-CHDPs. CONCLUSION: Although XBB.1.16 specific neutralizing antibody levels were low in BA.5-CHDPs, these levels cannot predict the risk of reinfection; other potential risk factors need to be investigated in the future.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19 , Imunidade Humoral , Diálise Renal , SARS-CoV-2 , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , China/epidemiologia , COVID-19/imunologia , Vacinas contra COVID-19/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Reinfecção/imunologia , Fatores de Risco , SARS-CoV-2/classificação , SARS-CoV-2/imunologia , SARS-CoV-2/fisiologia , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Vacinação
14.
Virus Genes ; 47(1): 20-6, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23749101

RESUMO

Influenza A H3N2 virus caused 1968 Hong Kong influenza pandemic, and has since been one of the most prevalent seasonal influenza viruses in global populations, representing a credible pandemic candidate in future. Previous studies have established that the hemagglutinin (HA) protein is the predominant antigen and executes receptor binding and membrane fusion. Homologous sequence analysis of all HA subtypes of influenza viruses revealed that two cysteine residues (540 and 544) are uniquely present in the transmembrane domain (TM) of HA proteins from all influenza A H3N2 viruses. However, the functions of these two cysteines have not been fully studied. Here, we generated three mutants (C540S, C544L, and 2C/SL) to investigate the effects of the two TM cysteines on the biological functions of H3 HA. We herein presented evidences that the mutations of one or two of the cysteines did not affect the proper expressions of HA proteins in cells, and more importantly all mutant H3 HAs showed decreased thermal stability but increased fusion activity in comparison with wildtype HA. Our results taken together demonstrated that the two TM cysteines are important for the biological functions of H3 HA proteins.


Assuntos
Cisteína/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vírus da Influenza A Subtipo H3N2/metabolismo , Influenza Humana/virologia , Mutação de Sentido Incorreto , Linhagem Celular , Cisteína/metabolismo , Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Temperatura Alta , Humanos , Vírus da Influenza A Subtipo H3N2/química , Vírus da Influenza A Subtipo H3N2/genética , Estabilidade Proteica , Estrutura Terciária de Proteína
15.
J Clin Tuberc Other Mycobact Dis ; 32: 100378, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37293271

RESUMO

Purpose: To examine the relationship between the positive rate and types of necrosis in pathological examinations of tuberculosis granulomas with necrosis, to improve the detection rate of positive cases. Methods: Specimens from 381 patients were collected in Wuhan Pulmonary Hospital from Jan 2022 to Feb 2023. The samples were examined using various methods such as AFB smear microscopy, mycobacterial culture, PCR, SAT-TB, and X-pert MTB/RIF rapid molecular detection. Result: There were 3 types of necrosis. Including 270 cases of caseous necrosis, 30 cases of coagulation necrosis, and 76 cases of an abscess. Five cases were non-necrotizing granulomas.In the pathological specimen testing for tuberculosis, five detection techniques were used and their positive rates detected in descending order were X-pert, TBDNA, SAT-TB, tuberculosis culture, AFB. Comparison between different examinations in the group: X-pert had the highest positive rate in each group, and it was significantly higher than TBDNA (P < 0.01) in caseous necrosis specimens. Compared with the same examination between the groups, the detection rates of X-pert and TBDNA in abscess and caseous necrosis specimens were significantly higher than in coagulation necrosis specimens (P < 0.01). Conclusion: The positive rates of the five etiological detection techniques in tuberculous granuloma with different types of necrosis were quite different. The specimens of caseous necrosis or abscess could be selected for detection, and X-pert had the highest positive rate.

16.
J Dermatolog Treat ; 34(1): 2199106, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37010492

RESUMO

AIM: This study aimed to evaluate the efficacy and safety of bimekizumab for psoriasis. METHODS: The PubMed, Web of Science, Cochrane Library, and Embase databases were systematically searched until November 20, 2022, to identify randomized controlled trials (RCTs) reporting the efficacy and safety of bimekizumab. The identified studies were screened according to inclusion and exclusion criteria, and a meta-analysis was performed on the selected studies using the Stata (version 17.0) software to investigate the efficacy and safety of bimekizumab. RESULTS: Six studies involving 1252 participants were considered. Compared with the control group which received placebo, the bimekizumab group had a larger number of patients with improvement in Psoriasis Area and Severity Index (PASI) of at least 75% (PASI75) (RR: 20.54, 95%CI: 12.41-33.99; p = .000), at least 90% (PASI90) (RR:16.99, 95%CI: 7.09-40.68; p = .000) and 100%(PASI100) (RR:14.57; 95%CI: 5.26-40.35; p = .000) and a larger number with improvement in Investigator Global Assessment (IGA) response (RR:22.57; 95%CI: 12.74-39.98; p = .000). There was no obvious difference between the bimekizumab and placebo groups in treatment of emergent adverse events (TEAEs) (RR:1.17; 95%CI: 0.93-1.47; p > .05) and serious TEAEs (RR: 0.67; 95%CI: 0.28-1.61; p > .05). CONCLUSIONS: Bimekizumab shows promising efficacy for the treatment of psoriasis with favorable safety records.


Assuntos
Psoríase , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Psoríase/tratamento farmacológico , Anticorpos Monoclonais Humanizados/uso terapêutico , Índice de Gravidade de Doença
17.
Int J Gen Med ; 16: 3447-3455, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37601808

RESUMO

Introduction: Tracheobronchopathia osteochondroplastica (TO) is a relatively rare benign tracheobronchial disease, which is often misdiagnosed or missed. To date, there is no specific treatment for TO. The aim of this study was to investigate the clinical manifestations, imaging features, bronchoscopy results, pathological findings, and diagnostic points of TO. Patients and methods: A total of 33 patients diagnosed with TO were enrolled. Clinical data were collected using retrospective methods in the period from January 2021 and November 2022. Descriptive analysis was used. Results: Patients included 17 (51.5%) male and 16 (48.5%) female, with a median age of 54 years. The main clinical manifestations included cough in 15 cases, fever in 6 cases, chest tightness in 4 cases, haemoptysis in 3 cases, and chest pain in 4 cases. The time from the onset of symptoms to diagnosis was 1 week to 96 months. Some patients were diagnosed with other lung diseases, including 16 patients with tuberculosis, 2 patients with lung cancer, 3 patients with nontuberculous mycobacteriosis, 3 patients with tuberculous pleurisy, 2 patients with bronchiectasis, and 1 patient with pneumonia. Chest computed tomography (CT) scan demonstrated calcified nodules in 10 (30.3%) patients. In bronchoscopy, entire tracheal involvement was found in 21 (63.6%) patients, 12 (36.4%) patients were found to have involvement of only part of the trachea. The patients were divided into three groups according to the bronchoscopic presentation, the largest proportion was stage II (19/33), followed by stage I (8/33) and stage III (6/33). Histopathological findings showed squamous metaplasia, cartilaginous, and bony tissues. Conclusion: TO is a slowly progressing disease with non-specific clinical symptoms and a low positive rate of imaging diagnosis, making it susceptible to misdiagnosis and missed diagnosis. The disease needs to be diagnosed by combining imaging features, fiberoptic bronchoscopy, and pathological findings.

18.
Virus Res ; 337: 199235, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37788720

RESUMO

Enterovirus A71 (EV-A71), coxsackievirus A16 (CV-A16), and CV-A10 belong to the main prevailing types causing hand-foot-and-mouth disease. Since EV-A71 monovalent vaccine does not confer cross-protection, developing a multivalent vaccine is essential. In this study, a trivalent chimeric virus-like particle of EV-A71 (EV-A71-VLPCHI3) was constructed based on EV-A71-VLP backbone by replacing the corresponding surface loops with CV-A16 VP1 G-H, CV-A10 VP1 B-C and E-F loops, which are critical for immunogenic neutralization. The baculovirus-insect cell expression system was employed for EV-A71-VLPCHI3 production. EV-A71-VLPCHI3 was purified by sucrose density gradient and observed by transmission electron microscopy. The immunogenicity and protective efficacy of EV-A71-VLPCHI3 were evaluated in mice. Our results revealed that EV-A71-VLPCHI3 had a similar morphology to inactivated EV-A71 particles and could induce specific IgG antibodies against EV-A71, CV-A16 and CV-A10 in mice. More importantly, EV-A71-VLPCHI3 enhanced cross-reactive protection against CV-A16 and CV-A10, by 20 % and 40 %, compared to inactivated EV-A71 counterparts, respectively. In conclusion, the successful construction of EV-A71-VLPCHI3 suggested that loop-dependent heterologous protection could be transferred by loops replacement on the surface of viral capsid. This strategy may also supplement the development of multivalent vaccines against other infectious viral diseases.


Assuntos
Enterovirus Humano A , Infecções por Enterovirus , Enterovirus , Doença de Mão, Pé e Boca , Animais , Camundongos , Enterovirus Humano A/genética , Infecções por Enterovirus/prevenção & controle , Antígenos Virais
19.
Cancer Manag Res ; 15: 165-174, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36824151

RESUMO

Purpose: Non-small-cell lung cancer (NSCLC) comprises approximately 80% of all lung malignancies. The 5-year survival rate of patients with advanced lung cancer who lost their chances of surgery is approximately 15%. Suitable animal models are important in screening individualized treatment plans for patients with lung cancer, evaluating the pre-clinical efficacy of new drugs, and conducting basic research. Patients and Methods: In this study, we collected malignant pleural effusion (MPE) samples from 31 patients with NSCLC, successfully constructed 11 NSCLC patient-derived xenografts (PDXs), and analyzed the factors affecting their successful establishment. Primary PDX tumors were characterized using histological analysis, immunohistochemistry, short tandem repeat (STR) profiling, and cytogenetic analysis. Results: The PDXs preserved the histopathology and protein expression pattern of parental tumors. STR analysis revealed the PDX tissue and a tumor tissue of the same individual origin. Statistical analysis showed that the survival time of patients reflected the malignant degree of MPEs to a certain extent, thus affecting the establishment of PDXs. However, the age, gender, and clinical and biochemical indicators of the patients did not affect the establishment of PDX models. Conclusion: These data suggest that the established NSCLC PDXs preserved the molecular characteristics of primary lung cancer and can serve as a new tool to elucidate the pathogenesis of tumors, explore new treatment methods, and conduct the research and development of new drugs for tumors.

20.
J Clin Rheumatol ; 18(1): 23-7, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22157268

RESUMO

BACKGROUND: Dual-energy computed tomography (DECT) has recently been described as a sensitive method to detect urate deposits in patients with gout. OBJECTIVES: The aim of this study was to compare the reproducibility of DECT with various physical measurement methods of tophus size assessment. METHODS: Sixty-four tophi from 25 patients were analyzed. Each tophus was assessed by 2 independent observers using Vernier calipers and tape measure. All patients proceeded to DECT scanning of both feet. Urate volume within index tophi was assessed by 2 independent observers using automated DECT volume assessment software (n = 55 tophi). Five patients returned within 1 week for repeat physical assessment of tophus size. Dual-energy computed tomography scans from the returning patients were scored twice by both observers. Intraobserver and interobserver reproducibility was assessed by intraclass correlation coefficient (ICC) and limits-of-agreement analysis. RESULTS: Overall, DECT was more reproducible than the physical methods with interobserver ICCs for DECT of 0.95, for calipers 0.78, and for tape measurement 0.88, and intraobserver ICCs for DECT of 1.00, for calipers 0.75, and for tape measurement 0.91. Vernier caliper and tape measurements correlated highly with each other (rs = 0.84, P < 0.0001) but less well with DECT (for index tophi, r(s) = 0.46, P = 0.004 for both). Large variation was observed in the amount of urate deposits documented by DECT in tophi of similar physical size. CONCLUSIONS: Dual-energy computed tomography scanning is a highly reproducible method for measuring urate deposits within tophi. This imaging modality reveals the composition of tophi that contain variable urate deposits embedded within soft tissue.


Assuntos
Gota/diagnóstico por imagem , Exame Físico/métodos , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Ácido Úrico/análise
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