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1.
PLoS Pathog ; 19(2): e1010812, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36795772

RESUMO

Hepatitis C virus NS5A is a multifunctional phosphoprotein comprised of three domains (DI, DII and DIII). DI and DII have been shown to function in genome replication, whereas DIII has a role in virus assembly. We previously demonstrated that DI in genotype 2a (JFH1) also plays a role in virus assembly, exemplified by the P145A mutant which blocked infectious virus production. Here we extend this analysis to identify two other conserved and surface exposed residues proximal to P145 (C142 and E191) that exhibited no defect in genome replication but impaired virus production. Further analysis revealed changes in the abundance of dsRNA, the size and distribution of lipid droplets (LD) and the co-localisation between NS5A and LDs in cells infected with these mutants, compared to wildtype. In parallel, to investigate the mechanism(s) underpinning this role of DI, we assessed the involvement of the interferon-induced double-stranded RNA-dependent protein kinase (PKR). In PKR-silenced cells, C142A and E191A exhibited levels of infectious virus production, LD size and co-localisation between NS5A and LD that were indistinguishable from wildtype. Co-immunoprecipitation and in vitro pulldown experiments confirmed that wildtype NS5A domain I (but not C142A or E191A) interacted with PKR. We further showed that the assembly phenotype of C142A and E191A was restored by ablation of interferon regulatory factor-1 (IRF1), a downstream effector of PKR. These data suggest a novel interaction between NS5A DI and PKR that functions to evade an antiviral pathway that blocks virus assembly through IRF1.


Assuntos
Hepatite A , Hepatite C , Humanos , Hepacivirus/fisiologia , Proteínas não Estruturais Virais/metabolismo , Montagem de Vírus/fisiologia , Vírion/metabolismo , Replicação Viral
2.
J Gen Virol ; 104(9)2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37672027

RESUMO

The hepatitis C virus (HCV) NS5A protein is comprised of three domains (D1-3). Previously, we observed that two alanine substitutions in D1 (V67A, P145A) abrogated replication of a genotype 2a isolate (JFH-1) sub-genomic replicon (SGR) in Huh7 cells, but this phenotype was partially restored in Huh7.5 cells. Here we demonstrate that five additional residues, surface-exposed and proximal to V67 or P145, exhibited the same phenotype. In contrast, the analogous mutants in a genotype 3a isolate (DBN3a) SGR exhibited different phenotypes in each cell line, consistent with fundamental differences in the functions of genotypes 2 and 3 NS5A. The difference between Huh7 and Huh7.5 cells was reminiscent of the observation that cyclophilin inhibitors are more potent against HCV replication in the former and suggested a role for D1 in cyclophilin dependence. Consistent with this, all JFH-1 and DBN3a mutants exhibited increased sensitivity to cyclosporin A treatment compared to wild-type. Silencing of cyclophilin A (CypA) in Huh7 cells inhibited replication of both JFH-1 and DBN3a. However, in Huh7.5 cells CypA silencing did not inhibit JFH-1 wild-type, but abrogated replication of all the JFH-1 mutants, and both DBN3a wild-type and all mutants. CypB silencing in Huh7 cells had no effect on DBN3a, but abrogated replication of JFH-1. CypB silencing in Huh7.5 cells had no effect on either SGR. Lastly, we confirmed that JFH-1 NS5A D1 interacted with CypA in vitro. These data demonstrate both a direct involvement of NS5A D1 in cyclophilin-dependent genome replication and functional differences between genotype 2 and 3 NS5A.


Assuntos
Ciclofilinas , Hepatite C , Humanos , Genótipo , Hepacivirus , Replicação Viral
3.
J Gen Virol ; 104(11)2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37942835

RESUMO

Hepatitis E virus (HEV) is an emerging pathogen responsible for more than 20 million cases of acute hepatitis globally per annum. Healthy individuals typically have a self-limiting infection, but mortality rates in some populations such as pregnant women can reach 30 %. A detailed understanding of the virus lifecycle is lacking, mainly due to limitations in experimental systems. In this regard, the cyclophilins are an important family of proteins that have peptidyl-prolyl isomerase activity and play roles in the replication of a number of positive-sense RNA viruses, including hepatotropic viruses such as hepatitis C virus (HCV). Cyclophilins A and B (CypA/B) are the two most abundant Cyps in hepatocytes and are therefore potential targets for pan-viral therapeutics. Here, we investigated the importance of CypA and CypB for HEV genome replication using sub-genomic replicons. Using a combination of pharmacological inhibition by cyclosporine A (CsA), and silencing by small hairpin RNA we find that CypA and CypB are not essential for HEV replication. However, we find that silencing of CypB reduces replication of some HEV isolates in some cells. Furthermore, sensitivity to Cyp silencing appears to be partly conferred by the sequence within the hypervariable region of the viral polyprotein. These data suggest HEV is atypical in its requirements for cyclophilin for viral genome replication and that this phenomenon could be genotype- and sequence-specific.


Assuntos
Hepatite C , Vírus da Hepatite E , Gravidez , Feminino , Humanos , Ciclofilinas/genética , Ciclofilinas/metabolismo , Vírus da Hepatite E/genética , Hepacivirus/genética , Ciclosporina/farmacologia , Replicação Viral
4.
J Clin Nurs ; 32(17-18): 5632-5651, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36946424

RESUMO

BACKGROUND: Some traditional Chinese medicine (TCM)-based integrated health interventions have been used for depression, but pooled efficacy remains unknown. AIMS AND OBJECTIVES: This study aimed to systematically evaluate the efficacy of TCM-based integrated health interventions for relieving depression. DESIGN: Systematic review and meta-analysis. METHODS: A comprehensive literature search was conducted on 17 databases from inception up to June 2022. Randomised controlled trials (RCTs) that examined an integrated health intervention based on TCM theory for depression were included. The risk of bias was assessed using the second version of the Cochrane risk-of-bias tool for randomised trials, and the quality of evidence was evaluated using the Grading of Recommendations, Assessment, Development and Evaluation system. RESULTS: Eighteen RCTs with a total of 1448 depressed participants were included. Health care providers, mainly nurses (14 studies), implemented TCM-based integrated health interventions. The pooled results showed that TCM-based integrated health interventions had larger effects on reducing depressive symptoms (15 studies; standardised mean difference = -2.05; 95% CI: -2.74, -1.37; p < .00001) compared with usual care at posttreatment but showed no significant difference contrasted to cognitive behavioural therapy (two studies, p = .31). However, the overall evidence was low. CONCLUSIONS: The meta-analysis results indicated that TCM-based integrated health interventions were effective in reducing depression. However, the results should be interpreted with caution because of the low quality of the included studies. Future RCTs with rigorous designs should be conducted to provide robust evidence of the efficacy of TCM-based integrated health interventions in treating depression. RELEVANCE TO CLINICAL PRACTICE: TCM-based integrated health interventions might be a potentially effective alternative for depression. Nurses could play an important role in designing and providing TCM-based integrated nursing interventions for patients with depression. NO PATIENT OR PUBLIC CONTRIBUTION: This is a systematic review and meta-analysis based on data from previous studies.


Assuntos
Terapia Cognitivo-Comportamental , Psicoterapia , Humanos , Psicoterapia/métodos , Depressão/terapia , Depressão/etiologia , Medicina Tradicional Chinesa , Terapia Cognitivo-Comportamental/métodos
5.
Int J Nurs Pract ; 29(4): e13181, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37435848

RESUMO

BACKGROUND: Falls lead to numerous negative health outcomes and jeopardize the physical function and quality of life in older adults. Cognitive impairment and physical frailty were found to be associated with the risk of falls, but there was no systematic review that estimated the association between cognitive frailty and the risk of falls. METHODS: A systematic literature search of the cross-sectional, cohort, and case-control studies in Cochrane library, Scopus, CINAHL, EMBASE and PsycINFO was conducted on 3 September 2021. Study quality was assessed by using the Joanna Briggs Institute critical appraisal tool. A random effects meta-analysis was performed to estimate the odds ratio of the incidence of falls in older adults with cognitive frailty. RESULTS: Seven studies were included. The overall quality of the included studies was acceptable. The meta-analysis of cohort studies showed older adults aged 60 and above with cognitive frailty had a pooled odds ratio of 1.45 (95% confidence interval 1.30, 1.61) for at least one fall compared with those without cognitive frailty. The meta-analysis of cross-sectional studies showed that the odds of older adults with cognitive frailty experiencing at least one fall was 1.64 times (95% confidence interval 1.51, 1.79) higher than those without cognitive frailty. CONCLUSION: The association between cognitive frailty and the risk of falls is statistically significant. Timely detection of cognitive frailty is essential especially in the community nursing level for preventing falls.


Assuntos
Fragilidade , Humanos , Idoso , Fragilidade/complicações , Fragilidade/epidemiologia , Qualidade de Vida , Estudos Transversais , Cognição , Idoso Fragilizado
6.
J Am Chem Soc ; 144(38): 17576-17587, 2022 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-36102706

RESUMO

Flower-like polyacrylonitrile (PAN) particles have shown promising performance for numerous applications, including sensors, catalysis, and energy storage. However, the detailed formation process of these unique structures during polymerization has not been investigated. Here, we elucidate the formation process of flower-like PAN particles through a series of in situ and ex situ experiments. We have the following key findings. First, lamellar petals within the flower-like particles were predominantly orthorhombic PAN crystals. Second, branching of the lamellae during the particle formation arose from PAN's fast nucleation and growth on pre-existing PAN crystals, which was driven by the poor solubility of PAN in the reaction solvent. Third, the particles were formed to maintain a constant center-to-center distance during the reaction. The separation distance was attributed to strong electrostatic repulsion, which resulted in the final particles' spherical shape and uniform size. Lastly, we employed the understanding of the formation mechanism to tune the PAN particles' morphology using several experimental parameters including incorporating comonomers, changing temperature, adding nucleation seeds, and adjusting the monomer concentration. These findings provide important insights into the bottom-up design of advanced nanostructured PAN-based materials and controlled polymer nanostructure self-assemblies.


Assuntos
Resinas Acrílicas , Polímeros , Tamanho da Partícula , Polímeros/química , Solventes
7.
J Gen Virol ; 102(1)2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33141008

RESUMO

Hepatitis C virus (HCV) genotype 3 presents a high level of both baseline and acquired resistance to direct-acting antivirals (DAAs), particularly those targeting the NS5A protein. To understand this resistance we studied a cohort of Brazilian patients treated with the NS5A DAA, daclatasvir and the nucleoside analogue, sofosbuvir. We observed a novel substitution at NS5A amino acid residue 98 [serine to glycine (S98G)] in patients who relapsed post-treatment. The effect of this substitution on both replication fitness and resistance to DAAs was evaluated using two genotype 3 subgenomic replicons. S98G had a modest effect on replication, but in combination with the previously characterized resistance-associated substitution (RAS), Y93H, resulted in a significant increase in daclatasvir resistance. This result suggests that combinations of substitutions may drive a high level of DAA resistance and provide some clues to the mechanism of action of the NS5A-targeting DAAs.


Assuntos
Antivirais/farmacologia , Carbamatos/farmacologia , Farmacorresistência Viral/genética , Hepacivirus/efeitos dos fármacos , Imidazóis/farmacologia , Pirrolidinas/farmacologia , Valina/análogos & derivados , Proteínas não Estruturais Virais/genética , Antivirais/uso terapêutico , Brasil , Carbamatos/uso terapêutico , Linhagem Celular Tumoral , Estudos de Coortes , Farmacorresistência Viral/efeitos dos fármacos , Quimioterapia Combinada , Genótipo , Hepacivirus/genética , Hepacivirus/fisiologia , Hepatite C/tratamento farmacológico , Hepatite C/virologia , Humanos , Imidazóis/uso terapêutico , Mutação , Pirrolidinas/uso terapêutico , Recidiva , Sofosbuvir/farmacologia , Sofosbuvir/uso terapêutico , Valina/farmacologia , Valina/uso terapêutico , Proteínas não Estruturais Virais/antagonistas & inibidores , Replicação Viral/genética
8.
J Gen Virol ; 101(11): 1182-1190, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32897181

RESUMO

Hepatitis C virus (HCV) is an important human pathogen causing 400 000 chronic liver disease-related deaths annually. Until recently, the majority of laboratory-based investigations into the biology of HCV have focused on the genotype 2 isolate, JFH-1, involving replicons and infectious cell culture systems. However, genotype 2 is one of eight major genotypes of HCV and there is great sequence variation among these genotypes (>30 % nucleotide divergence). In this regard, genotype 3 is the second most common genotype and accounts for 30 % of global HCV cases. Further, genotype 3 is associated with both high levels of inherent resistance to direct-acting antiviral (DAA) therapy, and a more rapid progression to chronic liver diseases. Neither of these two attributes are fully understood, thus robust genotype 3 culture systems to unravel viral replication are required. Here we describe the generation of robust genotype 3 sub-genomic replicons (SGRs) based on the adapted HCV NS3-NS5B replicase from the DBN3a cell culture infectious clone. Such infectious cell culture-adaptive mutations could potentially promote the development of robust SGRs for other HCV strains and genotypes. The novel genotype 3 SGRs have been used both transiently and to establish stable SGR-harbouring cell lines. We show that these resources can be used to investigate aspects of genotype 3 biology, including NS5A function and DAA resistance. They will be useful tools for these studies, circumventing the need to work under the biosafety level 3 (BSL3) containment required in many countries.


Assuntos
Hepacivirus/genética , Hepacivirus/fisiologia , Replicon , Antivirais/farmacologia , Carbamatos/farmacologia , Linhagem Celular Tumoral , Farmacorresistência Viral , Genoma Viral , Genótipo , Hepacivirus/efeitos dos fármacos , Hepatite C/tratamento farmacológico , Hepatite C/virologia , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Humanos , Mutação , Fosforilação , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo , Replicação Viral
9.
J Pharmacol Exp Ther ; 374(2): 252-263, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32493725

RESUMO

Deposition of hyperphosphorylated and aggregated tau protein in the central nervous system is characteristic of Alzheimer disease and other tauopathies. Tau is subject to O-linked N-acetylglucosamine (O-GlcNAc) modification, and O-GlcNAcylation of tau has been shown to influence tau phosphorylation and aggregation. Inhibition of O-GlcNAcase (OGA), the enzyme that removes O-GlcNAc moieties, is a novel strategy to attenuate the formation of pathologic tau. Here we described the in vitro and in vivo pharmacological properties of a novel and selective OGA inhibitor, MK-8719. In vitro, this compound is a potent inhibitor of the human OGA enzyme with comparable activity against the corresponding enzymes from mouse, rat, and dog. In vivo, oral administration of MK-8719 elevates brain and peripheral blood mononuclear cell O-GlcNAc levels in a dose-dependent manner. In addition, positron emission tomography imaging studies demonstrate robust target engagement of MK-8719 in the brains of rats and rTg4510 mice. In the rTg4510 mouse model of human tauopathy, MK-8719 significantly increases brain O-GlcNAc levels and reduces pathologic tau. The reduction in tau pathology in rTg4510 mice is accompanied by attenuation of brain atrophy, including reduction of forebrain volume loss as revealed by volumetric magnetic resonance imaging analysis. These findings suggest that OGA inhibition may reduce tau pathology in tauopathies. However, since hundreds of O-GlcNAcylated proteins may be influenced by OGA inhibition, it will be critical to understand the physiologic and toxicological consequences of chronic O-GlcNAc elevation in vivo. SIGNIFICANCE STATEMENT: MK-8719 is a novel, selective, and potent O-linked N-acetylglucosamine (O-GlcNAc)-ase (OGA) inhibitor that inhibits OGA enzyme activity across multiple species with comparable in vitro potency. In vivo, MK-8719 elevates brain O-GlcNAc levels, reduces pathological tau, and ameliorates brain atrophy in the rTg4510 mouse model of tauopathy. These findings indicate that OGA inhibition may be a promising therapeutic strategy for the treatment of Alzheimer disease and other tauopathies.


Assuntos
Inibidores Enzimáticos/farmacologia , Tauopatias/tratamento farmacológico , Tauopatias/metabolismo , beta-N-Acetil-Hexosaminidases/antagonistas & inibidores , Proteínas tau/metabolismo , Animais , Atrofia/tratamento farmacológico , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Modelos Animais de Doenças , Inibidores Enzimáticos/uso terapêutico , Locomoção/efeitos dos fármacos , Masculino , Camundongos , Células PC12 , Ratos , Tauopatias/patologia , Tauopatias/fisiopatologia
10.
Nat Mater ; 18(6): 594-601, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30988452

RESUMO

Stretchable semiconducting polymers have been developed as a key component to enable skin-like wearable electronics, but their electrical performance must be improved to enable more advanced functionalities. Here, we report a solution processing approach that can achieve multi-scale ordering and alignment of conjugated polymers in stretchable semiconductors to substantially improve their charge carrier mobility. Using solution shearing with a patterned microtrench coating blade, macroscale alignment of conjugated-polymer nanostructures was achieved along the charge transport direction. In conjunction, the nanoscale spatial confinement aligns chain conformation and promotes short-range π-π ordering, substantially reducing the energetic barrier for charge carrier transport. As a result, the mobilities of stretchable conjugated-polymer films have been enhanced up to threefold and maintained under a strain up to 100%. This method may also serve as the basis for large-area manufacturing of stretchable semiconducting films, as demonstrated by the roll-to-roll coating of metre-scale films.

11.
Arch Biochem Biophys ; 684: 108327, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32142890

RESUMO

Endometrial carcinoma is a type of gynecological cancer that originates in the endometrial epithelial tissue. Due to its high proliferation and ability to invade muscle tissue, it is one of the most common malignant tumors in the female reproductive system. Fatostatin is a small molecule non-sterol diarylthiazole derivative that acts as a chemical inhibitor of the sterol regulatory-element binding protein (SREBP) pathway. Previous studies have shown that fatostatin has an anti-tumor effect in some cancers. In this study, we investigated the effect of fatostatin on the growth, proliferation, apoptosis, migration and cell cycle of human endometrial carcinoma cells (HEC-1A and AN3 CA cells) using cholecystokinin (CCK) -8 method, clonogenicity assay, wound closure assay, Transwell migration assay and flow cytometer. We also examined its effect on the expression of apoptosis-associated protein (Caspase-3, Caspase-8 and Caspase-9) and level of lipid metabolism-related proteins, free fatty acid, and total cholesterol in cells. The growth of endometrial carcinoma xenografts was measured to confirm the effect of fatostatin in vivo. Our results showed that fatostatin inhibited the growth and proliferation of human endometrial carcinoma cells, changed their cell cycle and induced apoptosis. Based on the preliminary animal experiments, fatostatin also exhibited antitumor activity. The present study adds a new dimension to our understanding of the antitumor effects of fatostatin and provides an experimental basis for its use, and supports its potential value for clinical application.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias do Endométrio/tratamento farmacológico , Metabolismo dos Lipídeos/efeitos dos fármacos , Piridinas/uso terapêutico , Tiazóis/uso terapêutico , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Caspase 8/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Colesterol/metabolismo , Ácidos Graxos não Esterificados/metabolismo , Feminino , Humanos , Camundongos Endogâmicos BALB C , Piridinas/farmacologia , Tiazóis/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Angew Chem Int Ed Engl ; 59(10): 4043-4050, 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-31919948

RESUMO

Ni,N-doped carbon catalysts have shown promising catalytic performance for CO2 electroreduction (CO2 R) to CO; this activity has often been attributed to the presence of nitrogen-coordinated, single Ni atom active sites. However, experimentally confirming Ni-N bonding and correlating CO2 reduction (CO2 R) activity to these species has remained a fundamental challenge. We synthesized polyacrylonitrile-derived Ni,N-doped carbon electrocatalysts (Ni-PACN) with a range of pyrolysis temperatures and Ni loadings and correlated their electrochemical activity with extensive physiochemical characterization to rigorously address the origin of activity in these materials. We found that the CO2 R to CO partial current density increased with increased Ni content before plateauing at 2 wt % which suggests a dispersed Ni active site. These dispersed active sites were investigated by hard and soft X-ray spectroscopy, which revealed that pyrrolic nitrogen ligands selectively bind Ni atoms in a distorted square-planar geometry that strongly resembles the active sites of molecular metal-porphyrin catalysts.

13.
J Am Chem Soc ; 140(32): 10297-10304, 2018 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-30067349

RESUMO

Three-dimensional hierarchical porous carbon materials with flower-like superstructures are of great interest for energy applications since their unique shape not only provides high accessible surface area and consequently more exposed active sites but also facilitates ion transport for high-rate capability. However, finding a controllable way to make porous carbons with such specific shapes has been challenging. Herein, we report a tunable and simple method for one-pot synthesis of polyacrylonitrile and its copolymer nanostructured particles with various superstructures (flower, pompom, hairy leave, and petal shapes) controlled by employing various solvents or by the incorporation of different co-monomers. The correlation between polymer particle shapes and solvent properties has been identified through Hansen solubility parameters analysis. The obtained uniform polyacrylonitrile particles could be readily converted into porous carbons by high-temperature gas treatment while maintaining the original shape of the polymer precursor structures. The resulting carbon materials have high nitrogen-doping concentration (7-15 at%) and tunable porous structures. This novel synthetic method provides a simple way to make porous carbons with controllable morphology and potentially advantageous properties for a variety of potential energy and environmental applications, such as electrochemical energy conversion and wastewater treatment.

14.
J Am Chem Soc ; 140(44): 14533-14537, 2018 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-30176142

RESUMO

Conductive metal-organic frameworks (c-MOFs) have shown outstanding performance in energy storage and electrocatalysis. Varying the bridging metal species and the coordinating atom are versatile approaches to tune their intrinsic electronic properties in c-MOFs. Herein we report the first synthesis of the oxygen analog of M3(C6X6)2 (X = NH, S) family using Cu(II) and hexahydroxybenzene (HHB), namely Cu-HHB [Cu3(C6O6)2], through a kinetically controlled approach with a competing coordination reagent. We also successfully demonstrate an economical synthetic approach using tetrahydroxyquinone as the starting material. Cu-HHB was found to have a partially eclipsed packing between adjacent 2D layers and a bandgap of approximately 1 eV. The addition of Cu-HHB to the family of synthetically realized M3(C6X6)2 c-MOFs will enable greater understanding of the influence of the organic linkers and metals, and further broadens the range of applications for these materials.

15.
J Am Chem Soc ; 140(25): 7851-7859, 2018 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-29874062

RESUMO

Heteroatom-doped carbons have drawn increasing research interest as catalysts for various electrochemical reactions due to their unique electronic and surface structures. In particular, co-doping of carbon with boron and nitrogen has been shown to provide significant catalytic activity for oxygen reduction reaction (ORR). However, limited experimental work has been done to systematically study these materials, and much remains to be understood about the nature of the active site(s), particularly with regards to the factors underlying the activity enhancements of these boron-carbon-nitrogen (BCN) materials. Herein, we prepare several BCN materials experimentally with a facile and controlled synthesis method, and systematically study their electrochemical performance. We demonstrate the existence of h-BN domains embedded in the graphitic structures of these materials using X-ray spectroscopy. These synthesized structures yield higher activity and selectivity toward the 2e- ORR to H2O2 than structures with individual B or N doping. We further employ density functional theory calculations to understand the role of a variety of h-BN domains within the carbon lattice for the ORR and find that the interface between h-BN domains and graphene exhibits unique catalytic behavior that can preferentially drive the production of H2O2. To the best of our knowledge, this is the first example of h-BN domains in carbon identified as a novel system for the electrochemical production of H2O2.

16.
Am J Nephrol ; 48(6): 447-455, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30472707

RESUMO

BACKGROUND: Most people with chronic kidney disease (CKD) are not aware of their condition. OBJECTIVES: To assess screening criteria in identifying a population with or at high risk for CKD and to determine their level of control of CKD risk factors. METHOD: CKD Health Evaluation Risk Information Sharing (CHERISH), a demonstration project of the Centers for Disease Control and Prevention, hosted screenings at 2 community locations in each of 4 states. People with diabetes, hypertension, or aged ≥50 years were eligible to participate. In addition to CKD, screening included testing and measures of hemoglobin A1C, blood pressure, and lipids. -Results: In this targeted population, among 894 people screened, CKD prevalence was 34%. Of participants with diabetes, 61% had A1C < 7%; of those with hypertension, 23% had blood pressure < 130/80 mm Hg; and of those with high cholesterol, 22% had low-density lipoprotein < 100 mg/dL. CONCLUSIONS: Using targeted selection criteria and simple clinical measures, CHERISH successfully identified a population with a high CKD prevalence and with poor control of CKD risk factors. CHERISH may prove helpful to state and local programs in implementing CKD detection programs in their communities.


Assuntos
Programas de Rastreamento/estatística & dados numéricos , Insuficiência Renal Crônica/diagnóstico , Adolescente , Adulto , Idoso , Centers for Disease Control and Prevention, U.S. , Feminino , Humanos , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Inquéritos Nutricionais/estatística & dados numéricos , Projetos Piloto , Prevalência , Avaliação de Programas e Projetos de Saúde , Insuficiência Renal Crônica/epidemiologia , Medição de Risco/métodos , Medição de Risco/estatística & dados numéricos , Fatores de Risco , Estados Unidos/epidemiologia , Adulto Jovem
17.
Appl Microbiol Biotechnol ; 102(2): 961-970, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29184988

RESUMO

Classical swine fever virus (CSFV) is the causative agent of classical swine fever (CSF), a highly contagious and economically important disease of pigs. The envelope glycoprotein E2 of CSFV is the major antigen that induces neutralizing antibodies and confers protection against CSFV infections. Previously, we developed a murine monoclonal antibody (MAb), HQ06, against the E2 protein of CSFV. To produce the antibody conveniently and stably, the genes coding for the variable regions of the heavy and light chains of HQ06 and constant region genes from the swine antibody were fused and cloned into lentiviral expression vectors to express a recombinant porcinized MAb (rHQ06Sw) in mammalian cells. rHQ06Sw was able to react with the E2 protein or the CSFV virions specifically in different assays. Notably, rHQ06Sw could neutralize CSFV infection in a dose-dependent manner. Taken together, the functional porcinized MAb rHQ06Sw was generated, which can be used to develop novel diagnostic assays or to investigate the structure and functions of the E2 protein.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Vírus da Febre Suína Clássica , Proteínas do Envelope Viral/imunologia , Animais , Anticorpos Monoclonais/genética , Anticorpos Neutralizantes/genética , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/genética , Linhagem Celular , Engenharia Genética , Vetores Genéticos , Lentivirus , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Suínos
18.
J Virol ; 90(22): 10271-10283, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27605672

RESUMO

The mitogen-activated protein kinase kinase/extracellular regulated kinase (MEK1/2/ERK1/2) cascade is involved in the replication of several members of the Flaviviridae family, including hepatitis C virus and dengue virus. The effects of the cascade on the replication of classical swine fever virus (CSFV), a fatal pestivirus of pigs, remain unknown. In this study, MEK2 was identified as a novel binding partner of the E2 protein of CSFV using yeast two-hybrid screening. The E2-MEK2 interaction was confirmed by glutathione S-transferase pulldown, coimmunoprecipitation, and laser confocal microscopy assays. The C termini of E2 (amino acids [aa] 890 to 1053) and MEK2 (aa 266 to 400) were mapped to be crucial for the interaction. Overexpression of MEK2 significantly promoted the replication of CSFV, whereas knockdown of MEK2 by lentivirus-mediated small hairpin RNAs dramatically inhibited CSFV replication. In addition, CSFV infection induced a biphasic activation of ERK1/2, the downstream signaling molecules of MEK2. Furthermore, the replication of CSFV was markedly inhibited in PK-15 cells treated with U0126, a specific inhibitor for MEK1/2/ERK1/2, whereas MEK2 did not affect CSFV replication after blocking the interferon-induced Janus kinase-signal transducer and activator of transcription (JAK-STAT) signaling pathway by ruxolitinib, a JAK-STAT-specific inhibitor. Taken together, our results indicate that MEK2 positively regulates the replication of CSFV through inhibiting the JAK-STAT signaling pathway. IMPORTANCE Mitogen-activated protein kinase kinase 2 (MEK2) is a kinase that operates immediately upstream of extracellular regulated kinase 1/2 (ERK1/2) and links to Raf and ERK via phosphorylation. Currently, little is known about the role of MEK2 in the replication of classical swine fever virus (CSFV), a devastating porcine pestivirus. Here, we investigated the roles of MEK2 and the MEK2/ERK1/2 cascade in the growth of CSFV for the first time. We show that MEK2 positively regulates CSFV replication. Notably, we demonstrate that MEK2 promotes CSFV replication through inhibiting the interferon-induced JAK-STAT signaling pathway, a key antiviral pathway involved in innate immunity. Our work reveals a novel role of MEK2 in CSFV infection and sheds light on the molecular basis by which pestiviruses interact with the host cell.

19.
J Am Soc Nephrol ; 27(5): 1487-94, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26516209

RESUMO

Although management of multiple myeloma has changed substantially in the last decade, it is unknown whether the burden of ESRD due to multiple myeloma has changed, or whether survival of patients with multiple myeloma on RRT has improved. Regarding ESRD due to multiple myeloma necessitating RRT in the United States, we evaluated temporal trends between 2001 and 2010 for demography-adjusted incidence ratios, relative to rates in 2001-2002, and mortality hazards from RRT initiation, relative to hazards in 2001-2002. In this retrospective cohort study, we used the US Renal Data System database (n=1,069,343), 2001-2010, to identify patients with ESRD due to multiple myeloma treated with RRT (n=12,703). Demography-adjusted incidence ratios of ESRD from multiple myeloma decreased between 2001-2002 and 2009-2010 in the overall population (demography-adjusted incidence ratio 0.82; 95% confidence interval, 0.79 to 0.86) and in most demographic subgroups examined. Mortality rates were 86.7, 41.4, and 34.4 per 100 person-years in the first 3 years of RRT, respectively, compared with 32.3, 20.6, and 21.3 in matched controls without multiple myeloma. Unadjusted mortality hazards ratios declined monotonically after 2004 to a value of 0.72; 95% confidence interval, 0.67 to 0.77 in 2009-2010, and declines between 2001-2002 and 2008-2009 were observed (P<0.05) in most demographic subgroups examined. Findings were similar when adjustment was made for demographic characteristics, comorbidity markers, and laboratory test values. These data suggest the incidence of RRT from multiple myeloma in the United States has decreased in the last decade, and clinically meaningful increases in survival have occurred for these patients.


Assuntos
Falência Renal Crônica/epidemiologia , Falência Renal Crônica/etiologia , Mieloma Múltiplo/complicações , Adulto , Idoso , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Estados Unidos/epidemiologia
20.
J Am Chem Soc ; 138(3): 1001-9, 2016 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-26717034

RESUMO

Carbon capture and sequestration from point sources is an important component in the CO2 emission mitigation portfolio. In particular, sorbents with both high capacity and selectivity are required for reducing the cost of carbon capture. Although physisorbents have the advantage of low energy consumption for regeneration, it remains a challenge to obtain both high capacity and sufficient CO2/N2 selectivity at the same time. Here, we report the controlled synthesis of a novel N-doped hierarchical carbon that exhibits record-high Henry's law CO2/N2 selectivity among physisorptive carbons while having a high CO2 adsorption capacity. Specifically, our synthesis involves the rational design of a modified pyrrole molecule that can co-assemble with the soft Pluronic template via hydrogen bonding and electrostatic interactions to give rise to mesopores followed by carbonization. The low-temperature carbonization and activation processes allow for the development of ultrasmall pores (d < 0.5 nm) and preservation of nitrogen moieties, essential for enhanced CO2 affinity. Furthermore, our described work provides a strategy to initiate developments of rationally designed porous conjugated polymer structures and carbon-based materials for various potential applications.

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