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1.
Epilepsy Behav ; 150: 109570, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38070412

RESUMO

OBJECTIVE: Epidemiological studies have reported an association between epilepsy and dementia. However, the causal relationship between epilepsy and the risk of dementia is not clear. We aimed to inspect the causal effect of epilepsy on memory loss and dementia. METHODS: We analyzed summary data of epilepsy, memory loss, and dementia from the genome-wide association study (GWAS) using the two-sample Mendelian randomization (MR) method. We used the estimated odds ratio of memory loss and dementia associated with each of the genetically defined traits to infer evidence for a causal relationship with the following exposures: all epilepsy, focal epilepsy (including focal epilepsy with hippocampal sclerosis, lesion-negative focal epilepsy, and focal epilepsy with other lesions), and genetic generalized epilepsy (including childhood absence epilepsy, generalized tonic-clonic seizures alone, Juvenile absence epilepsy, and Juvenile myoclonic epilepsy). RESULTS: According to the result of MR using the inverse variance weighted method (IVW), we found that genetically predicted epilepsy did not causally increase the risk of memory loss and dementia (p > 0.05). Results of the MR-Egger and weighted median method were consistent with the IVW method. CONCLUSIONS: No evidence has been found to support the notion that epilepsy can result in memory loss and dementia. The associations observed in epidemiological studies could be attributed, in part, to confounding or nongenetic determinants.


Assuntos
Demência , Epilepsias Parciais , Epilepsia Tipo Ausência , Humanos , Criança , Análise da Randomização Mendeliana , Estudo de Associação Genômica Ampla , Epilepsia Tipo Ausência/complicações , Epilepsia Tipo Ausência/epidemiologia , Epilepsia Tipo Ausência/genética , Amnésia , Demência/complicações , Demência/epidemiologia , Demência/genética
2.
Macromol Rapid Commun ; 44(17): e2300162, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37114515

RESUMO

Smoke emission and smoke toxicity have drawn more attention to improving the fire safety of polymers. In this work, a polyoxometalates (POMs)-based hybrids flame retardant (P-AlMo6 ) epoxy resin (EP) is prepared with toxicity-reduction and smoke-suppression properties via a peptide coupling reaction between POMs and organic molecules with double DOPO (bisDOPA). It combines the good compatibility of the organic molecule and the superior catalytic performance of POMs. Compared to pure EP, the glass transition temperature and flexural modulus of EP composite with 5 wt.% P-AlMo6 (EP/P-AlMo6 -5) are raised by 12.3 °C and 57.75%, respectively. Notably, at low flame-retardant addition, the average CO to CO2 ratio (Av-COY/Av-CO2 Y) is reduced by 33.75%. Total heat release (THR) and total smoke production (TSP) are lowered by 44.4% and 53.7%, respectively. The Limited Oxygen Index (LOI) value achieved 31.7% and obtained UL-94 V-0 rating. SEM, Raman, X-ray photoelectron spectroscopy, and TG-FTIR are applied to analyze the flame-retardant mechanism in condensed and gas phase. Outstanding flame retardant, low smoke toxicity properties are attained due to the catalytic carbonization ability of metal oxides Al2 O3 and MoO3 produced from the breakdown of POMs. This work advances the development of POMs-based hybrids flame retardants with low smoke toxicity properties.


Assuntos
Resinas Epóxi , Retardadores de Chama , Fumaça , Dióxido de Carbono , Polímeros
3.
Carcinogenesis ; 43(5): 479-493, 2022 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-35134836

RESUMO

Human papillomavirus (HPV) E7 oncogene plays the most important role in cervical cancer. However, whether E7 oncoprotein is continuously expressed, associated with AKT(Ser473)/p-Src(Tyr527) signaling to trigger cervical carcinogenesis remains unclear. Here, we explored first if HPV16 E7 oncoprotein could be detected in clinical biopsies and is sustainedly expressed, and then investigated how this oncoprotein interacted with AKT(Ser473)/p-Src(Tyr527) signaling in cancer progression. We used ZHPV16E7384 affibody to detect E7 expression in HPV16-positive cervical cancer biopsies and animal tumors by immunohistochemistry (IHC). Results showed that ZHPV16E7384 affibody had intense and specific staining for E7 oncoprotein in the detected specimen. The E7 oncoprotein was continuously expressed to correspond with the development of precancerous lesions to invasive cervical cancer. IHC staining also revealed that AKT, p-AKT(Ser473), Src and p-Src(Tyr527) proteins were expressed in both patient biopsies and animal tumors, with the highest levels of p-AKT(Ser473)/p-Src(Tyr527) present in invasive cancer. Furthermore, siRNA experiments revealed that HPV16 E7 knockdown significantly impaired expression of p-AKT(Ser473)/p-Src(Tyr527) in both HPV16 E7-positive cancer cells and transformed cells. In addition, transient expression of HPV16 E7 protein promoted significantly expression of p-AKT(Ser473)/p-Src(Tyr527) in primary human keratinocytes. Finally, co-immunoprecipitation analysis proved that HPV 16 E7 protein interacted reciprocally with p-AKT(Ser473)/p-Src(Tyr527). In conclusion, we demonstrate that HPV16 E7 oncoprotein is continuously expressed to promote expression of p-AKT(Ser473)/p-Src(Tyr527) leading to drive the initiation and progression of cervical cancer. Our data provide a novel insight that HPV16 E7 activates p-AKT(Ser473)/p-Src(Tyr527) to establish a mechanistic link between the oncogene and the AKT/Src signaling to trigger cervical carcinogenesis.


Assuntos
Proteínas Oncogênicas Virais , Infecções por Papillomavirus , Lesões Pré-Cancerosas , Neoplasias do Colo do Útero , Animais , Carcinogênese , Feminino , Humanos , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/metabolismo , Proteínas E7 de Papillomavirus/genética , Proteínas E7 de Papillomavirus/metabolismo , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/genética , Lesões Pré-Cancerosas/genética , Proteínas Proto-Oncogênicas c-akt/genética , Neoplasias do Colo do Útero/patologia
4.
Small ; 18(33): e2203148, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35871499

RESUMO

Metallopolymers combine the property features of both metallic compounds and organic polymers, representing a typical direction for the design of high-performance hybrid materials. Here, a highly adaptive etching method to create pores and cavities in the metallopolymer particles is established. Starting from boronate polymer (BP) and inorganic@BP core-shell particles, porous, hollow, and yolk-shell metallopolymer particles can be fabricated, respectively. By taking advantage of the easy control over composition and pore/cavity structure, these metallopolymer particles provide a universal platform for the fabrication of nitrogen, boron co-doped carbon nanocomposites loaded with metals (M-NBCs). The as-prepared M-NBCs exhibit remarkable catalytic activities toward oxygen evolution reaction and hydrogen evolution reaction. An alkaline overall water splitting cell assembled by using M-NBCs as the anode and cathode can be driven by a single AAA battery. The proposed strategy for the construction of metallopolymer composites may enlighten for the design of complex hybrid nanomaterials.


Assuntos
Nanocompostos , Polímeros , Catálise , Nanocompostos/química , Polímeros/química , Porosidade , Água
5.
Nanotechnology ; 33(40)2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35732158

RESUMO

We report a simple metal ion-catechol coordination strategy to coat ruthenium-catechol polymer complex (TAC-Ru) on the surface of carbon nanotubes (CNT) to form a core-shell structure (abbreviated as CNT@TAC-Ru). This is achieved by firstly polymerizing catechol and boronic acid monomers on the surface of CNT to form a boronate ester polymer (BP) shell. Then, Ru3+is used to etch the BP shell, and cleave the dynamic boronate ester bond, leading to the formation of a CNT@ruthenium-catechol coordination complex based on the coordinative efficiency of the catechol group. The electrocatalytic property of the CNT@TAC-Ru composite can be activated through electrochemical cycling treatment. The as-activated CNT@TAC-Ru exhibits evidently improved hydrogen evolution reaction (HER) performance with an overpotential of 10 mV in 1.0 M KOH at a current density of 10 mA cm-2, which is better than that of commercial Pt/C (32 mV). And the long-term stability is also desirable. This work provides a pyrolysis-free method to form metal-polymer-carbon composite with high HER performance under the alkaline condition.

6.
Chem Soc Rev ; 50(12): 7330-7332, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34109331

RESUMO

Correction for 'Fluorescent glycoconjugates and their applications' by Baptiste Thomas et al., Chem. Soc. Rev., 2020, 49, 593-641, DOI: 10.1039/C8CS00118A.

7.
Microb Pathog ; 154: 104849, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33781869

RESUMO

BACKGROUND: Acute pancreatitis (AP) has a broad spectrum of severity and is associated with considerable morbidity and mortality. Dysbiosis of gut microbiota may be associated with AP severity. AIMS: We aimed to evaluate the composition and functional effects of gut microbiota in different grades of AP severity. METHODS: We carried out shotgun metagenomic sequencing on rectal swab samples from three patients with mild acute pancreatitis (MAP), three with moderately severe acute pancreatitis (MSAP), three with severe acute pancreatitis (SAP) and three normal control persons (NOR). Differences analysis in gut microbiota composition and functional enrichment was performed. RESULTS: Gut microbiota in AP patients was characterized by decreased species richness. The most representative gut microbiota in mild acute pancreatitis (MAP), moderately severe acute pancreatitis (MSAP), and severe acute pancreatitis (SAP) was Streptococcus, Escherichia-coli, and Enterococcus, respectively. Each of the three AP-associated genera could differentiate AP from healthy control population. Representative pathways associated with the glutathione metabolism, lipopolysaccharide biosynthesis, and amino acid metabolism (valine, leucine and isoleucine degradation) were enriched in MAP, MSAP, and SAP, respectively. CONCLUSIONS: The study shows a potential association of gut microbiome composition and function to the progression of AP severity.


Assuntos
Microbioma Gastrointestinal , Pancreatite , Doença Aguda , Disbiose , Humanos , Metagenômica
8.
BMC Cancer ; 21(1): 615, 2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34039309

RESUMO

BACKGROUND: Hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) remains a major public health problem and its pathogenesis remains unresolved. A recent proteomics study discovered a lipid enzyme Sterol O-acyltransferase (SOAT1) involvement in the progression of HCC. We aimed to explore the association between SOAT1 genetic variation and HCC. METHODS: We genotyped three exonic SOAT1 variants (rs10753191, V323V; rs3753526, L475L; rs13306731, Q526R) tagging most variations in the gene, in 221 HCC patients and 229 healthy individuals, to assess the impact of SOAT1 gene variation on risk of HCC occurrence. We further conducted immunohistochemistry to compare SOAT1 protein expression levels in 42 paired tumor and adjacent non-tumor tissues. RESULTS: We found that rs10753191 (Odds ratio (OR) = 0.58, P = 0.04) and a haplotype TGA (OR = 0.40, P = 0.01) were associated with reduced HCC risk after adjusting for lipid levels. In the immunohistochemistry experiment, we found that the protein expression of SOAT1 was significantly increased in the tumor compared with adjacent tissue (P < 0.001). CONCLUSION: This study revealed for the first time SOAT1 genetic variation that associates with host susceptibility to HCC occurrence. Our results suggest a role of SOAT1 in the HCC development, which warrants further elucidation.


Assuntos
Carcinoma Hepatocelular/genética , Predisposição Genética para Doença , Hepatite B Crônica/patologia , Neoplasias Hepáticas/genética , Esterol O-Aciltransferase/genética , Adulto , Idoso , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/virologia , Estudos de Casos e Controles , Feminino , Regulação Neoplásica da Expressão Gênica , Frequência do Gene , Voluntários Saudáveis , Vírus da Hepatite B/patogenicidade , Hepatite B Crônica/virologia , Humanos , Estimativa de Kaplan-Meier , Fígado/patologia , Fígado/virologia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Razão de Chances , Polimorfismo de Nucleotídeo Único , RNA-Seq , Esterol O-Aciltransferase/metabolismo
9.
Nanotechnology ; 32(39)2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34153959

RESUMO

Highly oriented Co-MOF nanoneedle arrays arein situconstructed on Co foam (Co-MOF@Co) by using a one-pot solvothermal strategy. As-prepared Co-MOF@Co can be directly served as a binder-free electrode for supercapacitor, which exhibits wonderful electrochemical performances, i.e. high specific capacitance (12783.0 mF cm-2or 1164.2 F g-1), exceptional cycling stability (90.5% retention over 10 000 cycles at 250 mA cm-2) with a loading of 10.98 mg cm-2. Meanwhile, an asymmetric supercapacitor of AC//Co-MOF@Co delivers a high ratability (87% retention upon ten-fold current density) and high energy density of 43.4 W h kg-1at the power density of 145.1 W kg-1.

10.
Environ Sci Technol ; 55(1): 730-737, 2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-33289377

RESUMO

Water pollution has become an environmental hazard. Diverse metal cations exist in wastewater; lead is the most common heavy metal pollutant among them. Selective removal of highly toxic and ultradiluted lead ions from wastewater is a major challenge for water purification. Here, selective capacitive removal (SCR) of lead ions from wastewater over redox-active molybdenum dioxide/carbon (MoO2/C) electrodes was developed by an environment-friendly asymmetric capacitive deionization (CDI) method. The MoO2/C spheres act as cathodes of an asymmetric CDI device and effectively reduce the concentration of Pb2+ from 50 ppm to <0.21 ppb. Moreover, the SCR efficiency of lead ions over redox-active MoO2/C electrodes is >99% in mixtures of 100 ppm Pb(NO3)2 and 100 ppm NaCl solutions. In addition, the electrodes exhibit high regeneration performance in mixtures of NaCl and Pb(NO3)2 and high SCR efficiency for lead ions from mixtures of heavy metal ions. The tetrahedral structure of the [MoO4] lattice is shown to be more favorable for the intercalation of lead ions. In situ Raman spectroscopy further shows that the transition of the crystal interface between [MoO6] and [MoO4] cluster lattice could be electrochemically controlled during SCR. Therefore, this study provides a new direction for the SCR of lead ions from wastewater.


Assuntos
Águas Residuárias , Purificação da Água , Eletrodos , Chumbo , Oxirredução
11.
J Clin Lab Anal ; 35(3): e23696, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33434308

RESUMO

BACKGROUND: Programmed death ligand 1 (PD-L1) has been used as a diagnostic marker to identify patients that will benefit from immune checkpoint inhibitors in non-small cell lung cancer (NSCLC). Immunohistochemistry with E1L3N clone is one of the most widely used and inexpensive laboratory-developed tests for PD-L1, but still need to be compared and validated with standard methods for clinical application. METHODS: We investigated the performance of E1L3N clone for PD-L1 testing in 299 tumor tissues of NSCLC patients and its comparability with FDA-approved 22C3 clone. RESULTS: The results show that the negative coincidence rate, weak positive coincidence rate, and positive coincidence rate were 97.4%, 92.2%, and 97.6% using the E1L3N assay relative to the 22C3 assay, respectively. An overall agreement of 96.3% was achieved between these two assays. We also found that the overall concordances were 97.8% and 93.9% for PD-L1 detection in large and small specimens, respectively, and no significant difference was obtained between these two assays (p = 0.076). In addition, the expression of PD-L1 was not detected in tumor tissues of benign lung disease using both the E1L3N and 22C3 assays. CONCLUSION: E1L3N can be used as a reliable alternative antibody clone to evaluate PD-L1 expression status for NSCLC patients.


Assuntos
Antígeno B7-H1/análise , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Imuno-Histoquímica/métodos , Neoplasias Pulmonares/metabolismo , Idoso , Anticorpos , Antígeno B7-H1/imunologia , Antígeno B7-H1/metabolismo , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
12.
Chem Soc Rev ; 49(2): 593-641, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31915764

RESUMO

Glycoconjugates and their applications as lectin ligands in biology have been thoroughly investigated in the past decades. Meanwhile, the intrinsic properties of such multivalent molecules were limited essentially to their ability to bind to their receptors with high selectivity and/or avidity. The present review will focus on multivalent glycoconjugates displaying an additional capability such as fluorescence properties not only for applications toward imaging of cancer cells and detection of proteins or pathogens but also for drug delivery systems toward targeted cancer therapy. This review is a collection of research articles discussed in the context of the structural features of fluorescent glycoconjugates organized according to their fluorescent core scaffold and with their representative applications.


Assuntos
Corantes Fluorescentes/química , Glicoconjugados/química , Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Fluorescência , Humanos , Neoplasias/tratamento farmacológico
13.
Mol Carcinog ; 59(5): 545-556, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32149414

RESUMO

Colorectal cancer (CRC) is a common malignancy. Many reports have implicated aberrant mitochondrial activity in the progression of CRC, with particular emphasis on the dysregulation of redox signaling and oxidative stress. In this study, we focused on manganese superoxide dismutase (MnSOD/SOD2), a key antioxidant enzyme, which maintains intracellular redox homeostasis. Current literature presents conflicting mechanisms for how SOD2 influences tumorigenesis and tumor progression. Here, we explored the role of SOD2 in CRC specifically. We found high levels of SOD2 expression in CRC tissues. We carried out a series of experiments to determine whether knockdown of SOD2 expression in CRC cell lines would reverse features of tumorigenesis. We found that reduced SOD2 expression decreased cell proliferation, migration, and invasion activity in CRC cells. Results from an additional series of experiments on mitochondrial function implicated a dual role for SOD2 in promoting CRC progression. First, proper level of SOD2 helped CRC cells maintain mitochondrial function by disposal of superoxide (O2.- ). Second, over-expression of SOD2 induced H2 O2 -mediated tumorigenesis by upregulating AMPK and glycolysis. Our results indicate that SOD2 may promote the occurrence and development of CRC by regulating the energy metabolism mediated by AMPK signaling pathways.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Transformação Celular Neoplásica/patologia , Neoplasias Colorretais/patologia , Metabolismo Energético , Mitocôndrias/patologia , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Movimento Celular , Proliferação de Células , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Glicólise , Humanos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Oxirredução , Estresse Oxidativo , Prognóstico , Superóxido Dismutase/genética , Células Tumorais Cultivadas
14.
Chemistry ; 26(63): 14445-14452, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-32864796

RESUMO

Two red-emitting dicyanomethylene-4H-pyran (DM) based fluorescent probes were designed and used for peroxynitrite (ONOO- ) detection. Nevertheless, the aggregation-caused quenching effect diminished the fluorescence and restricted their further applications. To overcome this problem, tetraphenylethylene (TPE) based glycoclusters were used to self-assemble with these DM probes to obtain supramolecular water-soluble glyco-dots. This self-assembly strategy enhanced the fluorescence intensity, leading to an enhanced selectivity and activity of the resulting glyco-dot comparing to DM probes alone in PBS buffer. The glyco-dots also exhibited better results during fluorescence sensing of intracellular ONOO- than the probes alone, thereby offering scope for the development of other similar supramolecular glyco-systems for chemical biological studies.


Assuntos
Corantes Fluorescentes , Imagem Óptica , Ácido Peroxinitroso , Piranos , Estilbenos , Corantes Fluorescentes/química , Corantes Fluorescentes/normas , Glicoconjugados/química , Imagem Óptica/métodos , Ácido Peroxinitroso/análise , Piranos/química , Estilbenos/química
15.
Environ Sci Technol ; 54(19): 12752-12760, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-32877168

RESUMO

Reducing the poisoning effect of alkali and heavy metals over ammonia selective catalytic reduction (NH3-SCR) catalysts is still an intractable issue, as the presence of K and Pb in fly ash greatly hampers their catalytic activity by impairing the acidity and affecting the redox properties of the catalysts, leading to the reduction in the lifetime of SCR catalysts. To address this issue, we propose a novel self-protected antipoisoning mechanism by designing SO42-/TiO2 superacid supported CeO2-SnO2 catalysts. Owing to the synergistic effect between CeO2 and SnO2 and the strong acidity originating from the SO42-/TiO2 superacid, the catalysts show superior catalytic activity over a wide temperature range (240-510 °C). Moreover, when K or/and Pb are deposited on SO42-/TiO2 catalysts, the bond effect between SO42- and Ti-O would be broken so that the sulfate in the bulk of SO42-/TiO2 superacid support would be induced to migrate to the surface to bond with K and Pb, thus prohibiting poisons from attacking the Ce-Sn active sites, and significantly boosting the resistance. Hopefully, this novel self-protection mechanism derived from the migration of sulfate in the SO42-/TiO2 superacid to resist alkali and heavy metals provides a new avenue for designing novel catalysts with outstanding resistance to alkali and heavy metals.


Assuntos
Álcalis , Metais Pesados , Amônia , Catálise , Oxirredução , Titânio
16.
Acta Biotheor ; 68(2): 295, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32108915

RESUMO

The authors have retracted this article [1] because they found a fundamental mistake in the methodology that is not correctable at this time. This mistake is found in the methodology and the derivation of the model with Tukey and Huber's losses. Because of the error, the findings in the article are not reliable. All authors agree to this retraction.

17.
Angew Chem Int Ed Engl ; 59(9): 3658-3664, 2020 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-31868285

RESUMO

With the ever-increasing threat posed by the multi-drug resistance of bacteria, the development of non-antibiotic agents for the broad-spectrum eradication of clinically prevalent superbugs remains a global challenge. Here, we demonstrate the simple supramolecular self-assembly of structurally defined graphene nanoribbons (GNRs) with a cationic porphyrin (Pp4N) to afford unique one-dimensional wire-like GNR superstructures coated with Pp4N nanoparticles. This Pp4N/GNR nanocomposite displays excellent dual-modal properties with significant reactive-oxygen-species (ROS) production (in photodynamic therapy) and temperature elevation (in photothermal therapy) upon light irradiation at 660 and 808 nm, respectively. This combined approach proved synergistic, providing an impressive antimicrobial effect that led to the complete annihilation of a wide spectrum of Gram-positive, Gram-negative, and drug-resistant bacteria both in vitro and in vivo. The study also unveils the promise of GNRs as a new platform to develop dual-modal antimicrobial agents that are able to overcome antibiotic resistance.


Assuntos
Anti-Infecciosos/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Luz , Nanocompostos/química , Anti-Infecciosos/química , Bactérias Gram-Negativas/efeitos dos fármacos , Grafite/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Nanocompostos/toxicidade , Nanotubos/química , Polietilenoglicóis/química , Porfirinas/química , Espécies Reativas de Oxigênio/metabolismo
18.
Chembiochem ; 20(14): 1856-1860, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-30295990

RESUMO

The sensitive imaging of amyloid-ß (Aß) peptides is important for the timely detection of neurodegenerative diseases, such as Alzheimer's disease (AD). Although clinically the diagnosis of AD relies on the use of radiolabeled imaging reagents, herein we report the simple construction of a "flat ensemble" formed between a quinoline-malononitrile AIEgen (EDS) and thin-layer molybdenum disulfide (2D MoS2 ) for the sensitive detection of Aß by means of fluorescence-based techniques. Self-assembly between EDS and 2D MoS2 in aqueous buffer solution produces the flat ensemble, and the subsequent interaction of the material ensemble with oligomeric and aggregated Aß peptides leads to up to 19-fold enhanced fluorescence of EDS. The ensemble is also applicable for staining Aß aggregates in vivo.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Dissulfetos/química , Corantes Fluorescentes/química , Molibdênio/química , Imagem Óptica/métodos , Quinolinas/química , Peptídeos beta-Amiloides/metabolismo , Animais , Encéfalo/patologia , Dissulfetos/metabolismo , Corantes Fluorescentes/metabolismo , Limite de Detecção , Masculino , Camundongos Endogâmicos ICR , Camundongos Transgênicos , Molibdênio/metabolismo , Fragmentos de Peptídeos/metabolismo , Quinolinas/metabolismo
19.
Org Biomol Chem ; 17(41): 9251-9256, 2019 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-31584602

RESUMO

We describe a novel green-emitting tetraphenylethylene-dicyanomethylene-4H-pyran (TPE-DCM) based fluorescent probe (TD-1). Conjugating TPE and DCM moieties allowed TD-1 to display high selectivity for thiophenol with excellent AIE properties in aqueous solution. Nevertheless, the poor water solubility of the hydrophobic structure resulted in a weak and unstable emission intensity. The non-covalent self-assembly of TD-1 with a TPE glycocluster (TPE2S) led to a largely improved water solubility producing a reliable and stable sensing system. The corresponding glyco-probe could sensitively detect exogenous thiophenol concentrations in PBS buffer or environmental water samples.

20.
Environ Sci Technol ; 53(2): 938-945, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30576117

RESUMO

Currently, selective catalytic reduction (SCR) of NO x with NH3 in the presence of SO2 by using vanadium-free catalysts is still an important issue for the removal of NO x for stationary sources. Developing high-performance catalysts for NO x reduction in the presence of SO2 is a significant challenge. In this work, a series of Fe2O3-promoted halloysite-supported CeO2-WO3 catalysts were synthesized by a molten salt treatment followed by the impregnation method and demonstrated improved NO x reduction in the presence of SO2. The obtained catalyst exhibits superior catalytic activity, high N2 selectivity over a wide temperature range from 270 to 420 °C, and excellent sulfur-poisoning resistance. It has been demonstrated that the Fe2O3-promoted halloysite-supported CeO2-WO3 catalyst increased the ratio of Ce3+ and the amount of surface oxygen vacancies and enhanced the interaction between active components. Moreover, the SCR reaction mechanism of the obtained catalyst was studied using in situ diffuse reflectance infrared Fourier transform spectroscopy. It can be inferred that the number of Brønsted acid sites is significantly increased, and more active species could be produced by Fe2O3 promotion. Furthermore, in the presence of SO2, the Fe2O3-promoted halloysite-supported CeO2-WO3 catalyst can effectively prevent the irreversible bonding of SO2 with the active components, making the catalyst exhibit desirable sulfur resistance. The work paves the way for the development of high-performance SCR catalysts with improved NO x reduction in the presence of SO2.


Assuntos
Cério , Argila , Amônia , Catálise , Vanádio
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