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1.
Small ; 19(44): e2303586, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37386814

RESUMEN

Piezocatalysis is an emerging technique that holds great promise for the conversion of ubiquitous mechanical energy into electrochemical energy through piezoelectric effect. However, mechanical energies in natural environment (such as wind energy, water flow energy, and noise) are typically tiny, scattered, and featured with low frequency and low power. Therefore, a high response to these tiny mechanical energies is critical to achieving high piezocatalytic performance. In comparison to nanoparticles or 1D piezoelectric materials, 2D piezoelectric materials possess characteristics such as high flexibility, easy deformation, large surface area, and rich active sites, showing more promise in future for practical applications. In this review, state-of-the-art research progresses on 2D piezoelectric materials and their applications in piezocatalysis are provided. First, a detailed description of 2D piezoelectric materials are offered. Then a comprehensive summary of the piezocatalysis technique is presented and examines the piezocatalysis applications of 2D piezoelectric materials in various fields, including environmental remediation, small-molecule catalysis, and biomedicine. Finally, the main challenges and prospects of 2D piezoelectric materials and their applications in piezocatalysis are discussed. It is expected that this review can fuel the practical application of 2D piezoelectric materials in piezocatalysis.

2.
J Nanobiotechnology ; 21(1): 149, 2023 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-37149605

RESUMEN

Surface-Enhanced Raman Scattering (SERS) technology, as a powerful tool to identify molecular species by collecting molecular spectral signals at the single-molecule level, has achieved substantial progresses in the fields of environmental science, medical diagnosis, food safety, and biological analysis. As deepening research is delved into SERS sensing, more and more high-performance or multifunctional SERS substrate materials emerge, which are expected to push Raman sensing into more application fields. Especially in the field of biological analysis, intrinsic and extrinsic SERS sensing schemes have been widely used and explored due to their fast, sensitive and reliable advantages. Herein, recent developments of SERS substrates and their applications in biomolecular detection (SARS-CoV-2 virus, tumor etc.), biological imaging and pesticide detection are summarized. The SERS concepts (including its basic theory and sensing mechanism) and the important strategies (extending from nanomaterials with tunable shapes and nanostructures to surface bio-functionalization by modifying affinity groups or specific biomolecules) for improving SERS biosensing performance are comprehensively discussed. For data analysis and identification, the applications of machine learning methods and software acquisition sources in SERS biosensing and diagnosing are discussed in detail. In conclusion, the challenges and perspectives of SERS biosensing in the future are presented.


Asunto(s)
Técnicas Biosensibles , COVID-19 , Nanoestructuras , Humanos , Espectrometría Raman/métodos , SARS-CoV-2 , Nanoestructuras/química , Nanotecnología , Técnicas Biosensibles/métodos
3.
Zhongguo Zhong Yao Za Zhi ; 48(18): 5024-5031, 2023 Sep.
Artículo en Zh | MEDLINE | ID: mdl-37802844

RESUMEN

Chemical constituents were isolated and purified from ethyl acetate fraction of Arctium lappa leaves by silica gel, ODS, MCI, and Sephadex LH-20 column chromatography. Their structures were identified with multiple spectroscopical methods including NMR, MS, IR, UV, and X-ray diffraction combined with literature data. Twenty compounds(1-20) were identified and their structures were determined as arctanol(1), citroside A(2), melitensin 15-O-ß-D-glucoside(3), 11ß,13-dihydroonopordopicrin(4), 11ß,13-dihydrosalonitenolide(5), 8α-hydroxy-ß-eudesmol(6), syringin(7), dihydrosyringin(8), 3,4,3',4'-tetrahydroxy-δ-truxinate(9),(+)-pinoresinol(10), phillygenin(11), syringaresinol(12), kaeperferol(13), quercetin(14), luteolin(15), hyperin(16), 4,5-O-dicaffeoylquinic acid(17), 1H-indole-3-carboxaldehyde(18), benzyl-ß-D-glucopyranoside(19), and N-(2'-phenylethyl) isobutyramide(20). Among them, compound 1 is a new norsesquiterpenoid, and compounds 2-5, 7-8, and 18-20 are isolated from this plant for the first time.


Asunto(s)
Arctium , Arctium/química , Espectroscopía de Resonancia Magnética , Luteolina/análisis , Hojas de la Planta/química
4.
Zhongguo Zhong Yao Za Zhi ; 48(21): 5809-5816, 2023 Nov.
Artículo en Zh | MEDLINE | ID: mdl-38114176

RESUMEN

Six compounds were isolated from aqueous extract of wine-processed Corni Fructus through silica gel, ODS column chromatography, Sephadex LH-20 gel column chromatography, reverse phase preparative HPLC and other chromatographic separation technologies. Their structures were identified with multiple spectroscopical methods including HR-ESI-MS, UV, IR, NMR and ECD and so on. Their structures were established as pinoresinoside B(1), cornusgallicacid A(2),(+)-isolariciresinol-9'-O-ß-glucopyranoside(3),(-)-isolariciresinol 3α-O-ß-D-glucopyranoside(4),(7R,8S)-dihydrodehydrodiconiferyl alcohol 9-O-ß-D-glucopyranoside(5), and(-)-seco isolariciresinol-9'-O-ß-D-glucopyranoside(6). Among them, compounds 1 and 2 were two new compounds. The biological activity evaluation results showed that compounds 2 and 6 had strong DPPH free radical scavenging ability, with EC_(50) values of(4.18±1.96) and(21.45±1.19) µmol·L~(-1), respectively. Compounds 1 and 2 had protective effects on H_2O_2-induced oxidative damage in NRK-52E cells in a dose-dependent manner, and the cell survival rate of compound 2 at 100 µmol·L~(-1) was 96.09%±1.77%.


Asunto(s)
Cornus , Vino , Naftoles , Lignina
5.
Genet Res (Camb) ; 2022: 1473260, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35919034

RESUMEN

Background: Both Lowe syndrome and Dent-2 disease are caused by variants in the OCRL gene. However, the reason why patients with similar OCRL gene mutations presented with different phenotypes remains uncertain. Methods: Children with hemizygous pathogenic or likely pathogenic variants in OCRL were compiled from published and unpublished consecutive cases from China. Furthermore, a Chi-square test was employed to analyze the correlation of the location and types of mutations on the phenotype of children with Lowe syndrome or Dent-2 disease. Results: Among the total 83 patients, 70.8% (34/48) cases of Lowe syndrome presented with truncating mutations, while only 31.4% (11/35) cases of Dent-2 disease presented with truncating mutation (Χ2 = 12.662; P < 0.001). Meanwhile, the majority of mutations in Dent-2 disease are located in Exon 2-12 (21/35, 60.0%), while the majority of mutations in Lowe syndrome are located in Exon 13-23 (39/48, 81.3%; Χ2 = 14.922; P < 0.001). Conclusions: Truncating mutations of the OCRL gene were more common in patients with Lowe syndrome than in Dent-2 disease, while mutation is more likely located at exon 2-12 in Dent-2 disease than that in Lowe syndrome. The type and location of mutation are important indicators for the phenotypes in patients with OCRL mutation. This is a large cohort study analyzing the genotype-phenotype correlation in patients with Lowe syndrome and Dent-2 disease in China. Our data may improve the interpretation of new OCRL variants and genetic counseling. Furthermore, a large international study would be necessary to illustrate the genotype-phenotype correlation in patients with OCRL mutations.


Asunto(s)
Síndrome Oculocerebrorrenal , Estudios de Cohortes , Estudios de Asociación Genética , Humanos , Mutación , Síndrome Oculocerebrorrenal/genética , Monoéster Fosfórico Hidrolasas/genética
6.
Epidemiol Infect ; 150: e43, 2022 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-35105410

RESUMEN

This review aimed to compare the clinical features and CT imaging features between patients with pulmonary tuberculosis (PTB) and lung cancer and patients with PTB alone. That would help to analyse the differences between the two and consequently providing a theoretical basis for the clinical diagnosis and treatment for the patients. Relevant case-control studies focusing on the clinical and CT imaging characteristics between PTB with lung cancer and PTB alone were systematically searched from five electronic databases. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for comparison. As of 2021-07-06, a total of 1735 articles were retrieved. But only 15 articles were finally included for meta-analysis. The results showed a higher proportion of irritable cough, haemorrhagic pleural effusion and lower proportion of night sweating in PTB patients with lung cancer than in PTB patients, and the differences were statistically significant (irritable cough: OR 2.43, 95% CI 1.43-4.11; haemorrhagic pleural effusion: OR 5.73, 95% CI 1.63-20.12; night sweating: OR 0.56, 95% CI 0.36-0.87). In addition, there are many differences in the imaging characteristics of the two types of patients. In conclusion, this review summarises the similarities and differences in clinical symptoms and imaging features between patients with PTB and lung cancer and patients with PTB alone, suggesting that we should be alert to the occurrence of lung cancer in patients with obsolete PTB relapse.


Asunto(s)
Neoplasias Pulmonares , Derrame Pleural , Tuberculosis Pulmonar , Estudios de Casos y Controles , Tos , Humanos , Neoplasias Pulmonares/complicaciones , Neoplasias Pulmonares/diagnóstico por imagen , Derrame Pleural/complicaciones , Tuberculosis Pulmonar/complicaciones , Tuberculosis Pulmonar/diagnóstico por imagen
7.
Bioorg Chem ; 127: 105940, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35749853

RESUMEN

Nine new cadinane-type sesquiterpenoids (1-9) and three new eucalyptane -type sesquiterpenes (10-12) were isolated from the ethyl acetate extract of Burdock leaves, which were commonly used for preventing or treating atherosclerosis in China. Their structures were confirmed by extensive spectroscopic analysis, single-crystal X-ray diffraction analysis and ECD calculations. Compound 1 possessed the rare large conjugated skeleton. All the isolates were evaluated for anti-inflammatory and cholesterol-lowering activities by the LPS- and oxidized-low-density-lipoprotein-stimulated RAW 264.7 cells, respectively. As the results, all isolates could decrease the productions of NO, and down-regulate the accumulation of cholesterol. Among them, 4 showed the most potent cholesterol-lowering effect. For the high content of 4 in the herb, mechanistic study of 4 was performed and the results showed that 4 markedly reduced the release of pro-inflammatory mediators which was probably associated with inhibition of the PI3K/Akt and 5-LOX signaling pathways. The findings of this study demonstrated the anti-inflammatory/cholesterol-lowering effects of the new sesquiterpenes from burdock leaves, which provides chemical basis and scientific evidence for the herb used as anti-atherosclerosis agents for the further study. The sesquiterpene lactones of burdock leaves are expected to become new small molecule inhibitors for the treatment of AS.


Asunto(s)
Arctium , Sesquiterpenos , Antiinflamatorios/química , Colesterol , Estructura Molecular , Fosfatidilinositol 3-Quinasas , Sesquiterpenos/química
8.
Zhongguo Zhong Yao Za Zhi ; 47(5): 1273-1278, 2022 Mar.
Artículo en Zh | MEDLINE | ID: mdl-35343154

RESUMEN

A new iridoid glycoside, cornushmf A(1) and nine known iridoids(2-10) were isolated from the water extract of the wine-processed Corni Fructus by various column chromatographies. Their chemical structures were identified by comprehensive spectroscopic methods as 7ß-O-(2″-formylfuran-5″-methylene)-morroniside(1), 7-dehydrologanin(2), sweroside(3), 7ß-O-methylmorroniside(4), 7α-O-methylmorroniside(5), 7ß-O-ethylmorroniside(6), 7α-O-ethylmorroniside(7), cornuside(8), sarracenin(9), and loganin(10).


Asunto(s)
Cornus , Medicamentos Herbarios Chinos , Vino , Cornus/química , Medicamentos Herbarios Chinos/química , Iridoides
9.
Molecules ; 26(7)2021 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-33805990

RESUMEN

Four new gallate derivatives-ornusgallate A, ent-cornusgallate A, cornusgallate B and C (1a, 1b, 2, 3)-were isolated from the wine-processed fruit of Cornus officinalis. Among them, 1a and 1b are new natural compounds with novel skeletons. Their chemical structures were elucidated by comprehensive spectroscopy methods including NMR, IR, HRESIMS, UV, ECD spectra and single-crystal X-ray diffraction analysis. The in vitro anti-inflammatory activities of all compounds were assayed in RAW 264.7 cells by assessing LPS-induced NO production. As the result, all compounds exhibited anti-inflammatory activities at attested concentrations. Among the tested compounds, compound 2 exhibited the strongest anti- inflammatory activity.


Asunto(s)
Antiinflamatorios , Cornus/química , Frutas/química , Ácido Gálico , Animales , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/farmacología , Ácido Gálico/análogos & derivados , Ácido Gálico/química , Ácido Gálico/aislamiento & purificación , Ácido Gálico/farmacología , Lipopolisacáridos/toxicidad , Ratones , Óxido Nítrico/metabolismo , Células RAW 264.7
10.
Angew Chem Int Ed Engl ; 59(17): 6827-6831, 2020 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-31971324

RESUMEN

The emerging metal single-atom catalyst has aroused extensive attention in multiple fields, such as clean energy, environmental protection, and biomedicine. Unfortunately, though it has been shown to be highly active, the origins of the activity of the single-atom sites remain unrevealed to date owing to the lack of deep insight on electronic level. Now, partially oxidized Ni single-atom sites were constructed in polymeric carbon nitride (CN), which elevates the photocatalytic performance by over 30-fold. The 3d orbital of the partially oxidized Ni single-atom sites is filled with unpaired d-electrons, which are ready to be excited under irradiation. Such an electron configuration results in elevated light response, conductivity, charge separation, and mobility of the photocatalyst concurrently, thus largely augmenting the photocatalytic performance.

11.
Brain Behav Immun ; 76: 48-60, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30414952

RESUMEN

Germinal centers (GC) are vital to adaptive immunity. BCL6 and miR-155 are implicated in control of GC reaction and lymphomagenesis. FBXO11 causes BCL6 degradation through ubiquitination in B-cell lymphomas. Chronic psychological stress is known to drive immunosuppression. Corticosterone (CORT) is an adrenal hormone expressed in response to stress and can similarly impair immune functions. However, whether GC formation is disrupted by chronic psychological stress and its molecular mechanism remain to be elucidated. To address this issue, we established a GC formation model in vivo, and a GC B cell differentiation model in vitro. Comparing Naive B cells to GC B cells in vivo and in vitro, the differences of BCL6 and FBXO11 mRNA do not match the changes at the protein level and miR-155 levels that were observed. Next we demonstrated that CORT increase, induced by chronic psychological stress, reduced GC response, IgG1 antibody production and miR-155 level in vivo. The effect of chronic psychological stress can be blocked by a glucocorticoid receptor (GR) antagonist. Similarly, impaired GC B cell generation and isotope class switching were observed. Furthermore, we found that miR-155 and BCL6 expression were downregulated, but FBXO11 expression was upregulated in GC B cells treated with CORT in vitro. In addition, we demonstrated that miR-155 directly down-regulated FBXO11 expression by binding to its 3́-untranslated region. The subsequent overexpression of miR-155 significantly blocked the stress-induced impairment of GC response, due to changes in FBXO11 and BCL6 expression, as well as increased apoptosis in B cells both in vivo and in vitro. Our findings suggest perturbation of GC reaction may play a role in chronic psychological stress-induced immunosuppression through a glucocorticoid pathway, and miR-155-mediated post-transcriptional regulation of FBXO11 and BCL6 expression may contribute to the impaired GC response.


Asunto(s)
Centro Germinal/metabolismo , MicroARNs/metabolismo , Estrés Psicológico/metabolismo , Animales , Apoptosis/fisiología , Linfocitos B/inmunología , Linfocitos B/metabolismo , Diferenciación Celular/inmunología , Proteínas de Unión al ADN/genética , Proteínas F-Box/metabolismo , Femenino , Centro Germinal/fisiología , Activación de Linfocitos , Masculino , Ratones , Ratones Endogámicos C57BL , MicroARNs/genética , Proteínas Proto-Oncogénicas c-bcl-6/metabolismo , Estrés Psicológico/fisiopatología
12.
Nanomedicine ; 20: 102019, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31125676

RESUMEN

How to eradicate Helicobacter pylori (H. pylori) in vivo with antibiotic resistance owns tremendous clinical requirement. Herein, gold nanostars were conjugated with acid-sensitive cis-aconitic anhydride modified anti-H. pylori polyclonal antibodies, resultant pH sensitive gold nanostars@H. pylori-antibodies nanoprobes (GNS@Ab) were employed for the theranostics of H. pylori in vivo. Photoacoustic imaging confirmed that prepared GNS@Ab could target actively H. pylori in the stomach. GNS@Ab nanoprobes could kill H. pylori in vivo in model animals under NIR laser irradiation, all GNS@Ab nanoprobes could be excreted out of gut within 7 days after oral administration. Gastric local lesion caused by H. pylori restored to normal status within one month. GNS@Ab nanoprobes within therapeutic doses did not damage intestinal bacteria imbalance. Forty clinical specimens of H. pylori with antibiotic resistance were verified validity of GNS@Ab nanoprobes. Prepared oral pH-sensitive GNS@Ab nanoprobes own clinical translational potential in the theranostics of H. pylori in near future.


Asunto(s)
Anticuerpos/farmacología , Microbioma Gastrointestinal , Oro/química , Helicobacter pylori/fisiología , Nanopartículas del Metal/química , Administración Oral , Animales , Muerte Celular/efectos de los fármacos , Módulo de Elasticidad , Femenino , Microbioma Gastrointestinal/efectos de los fármacos , Helicobacter pylori/efectos de los fármacos , Humanos , Concentración de Iones de Hidrógeno , Hipertermia Inducida , Nanopartículas del Metal/ultraestructura , Ratones Endogámicos BALB C , Técnicas Fotoacústicas , Fototerapia , Filogenia , Polietilenglicoles/química , Estómago/microbiología , Distribución Tisular/efectos de los fármacos
13.
Molecules ; 24(15)2019 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-31357638

RESUMEN

To obtain diterpene glycosides from an aqueous extract of the aerial parts of Isodon henryi and further investigate their cytotoxicities, in this study, a total of seven compounds were isolated, including six ent-kaurane diterpene glycosides (1-6) and one diterpene aglycon (7). Among the seven ent-kaurane diterpenes obtained, four were novel compounds, including ent-7,20-epoxy- kaur-16-en-1α,6ß,7ß,15ß-tetrahydroxyl-11-O-ß-d-glucopyranoside (1), ent-7,20-epoxy-kaur-16-en- 6ß,7ß,14ß,15ß-tetrahydroxyl-1-O-ß-d-glucopyranoside (2), ent-7,20-epoxy-kaur-16-en-6ß,7ß,15ß- trihydroxyl-1-O-ß-d-glucopyranoside (3), and ent-7,20-epoxy-kaur-16-en-7ß,11ß,14α,15ß-tetrahydr- oxyl-6-O-ß-d-glucopyranoside (4), and three were isolated from this plant for the first time (5-7). Their structures were elucidated by utilizing spectroscopic methods and electronic circular dichroism analyses. Furthermore, the cytotoxicities of all seven compounds were investigated in four human cancer cell lines, including A2780, BGC-823, HCT-116, and HepG2. The IC50 values of these diterpenes ranged from 0.18 to 2.44 mM in the tested cell lines. In addition, the structure-cytotoxicity relationship of diterpene glycosides was also evaluated to study the effect of glycosylation on the cytotoxicity of diterpene compounds.


Asunto(s)
Diterpenos de Tipo Kaurano/química , Diterpenos de Tipo Kaurano/farmacología , Glicósidos/química , Glicósidos/farmacología , Isodon/química , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Modelos Moleculares , Estructura Molecular , Análisis Espectral , Relación Estructura-Actividad
14.
Zhongguo Zhong Yao Za Zhi ; 44(2): 319-323, 2019 Jan.
Artículo en Zh | MEDLINE | ID: mdl-30989952

RESUMEN

The chemical constituents of the water extraction of the aerial parts of Isodon henryi were investigated by various chromatographic methods including D-101 macroporous adsorptive resins,silica gel,sephadex LH-20,and semi-preparative HPLC. As a result,ten compounds were separated and purified. By analyses of the UV,IR,MS,NMR spectra,their structures were determined as rabdosinate( 1),lasiokaurin( 2),epinodosinol( 3),rabdosichuanin C( 4),epinodosin( 5),hebeirubescensin k( 6),rubescensin C( 7),enmenol( 8),oridonin( 9),and enmenol-1-ß-glucoside( 10). Compounds 1-8 and 10 were isolated from I. henryi for the first time. Compounds 2 and 9 showed inhibitory effects against four tumor cells,with IC50 values of 2. 25-9. 32 µmol·L-1.


Asunto(s)
Isodon/química , Fitoquímicos/análisis , Extractos Vegetales/química , Espectroscopía de Resonancia Magnética , Estructura Molecular , Componentes Aéreos de las Plantas/química
15.
Artículo en Inglés | MEDLINE | ID: mdl-29914954

RESUMEN

The objective of this study was to investigate the efficacy and safety of 10-day bismuth quadruple therapy with amoxicillin, tetracycline, or clarithromycin and different doses of rabeprazole for first-line treatment of Helicobacter pylori infection. This multicenter, randomized, parallel-controlled clinical trial was conducted between March 2013 and August 2014. A total of 431 H. pylori-infected patients with duodenal ulcers were enrolled and randomized into four treatment groups (1:1:1:1) for 10 days, as follows: (i) a group receiving a low dose of rabeprazole of 10 mg twice a day (b.i.d.) (LR dose) plus bismuth, amoxicillin, and clarithromycin (LR-BAC); (ii) a group receiving LR plus bismuth, amoxicillin, and tetracycline (LR-BAT); (iii) a group receiving a high dose of rabeprazole of 20 mg b.i.d. (HR dose) plus bismuth, amoxicillin, and clarithromycin (HR-BAC); and (iv) a group receiving HR-BAT. Antimicrobial susceptibility was assessed by the Etest method. The primary outcome was H. pylori eradication at 4 weeks after the treatment. The per-protocol (PP) eradication rates in the LR-BAC, LR-BAT, HR-BAC, and HR-BAT groups were 94.1%, 91.9%, 94.8%, and 91.9%, respectively, while the intention-to-treat (ITT) eradication rates in those groups were 87.2%, 87.2%, 87.7%, and 86%, respectively. There was no significant difference between the four groups in PP analysis (P = 0.799) and ITT analysis (P = 0.985). The efficacies of four-treatment therapy were not affected by antibiotic resistance. The adverse events in the four treatment groups were similar; central nervous system (CNS) and gastrointestinal symptoms were the most common reported. Bismuth-containing quadruple therapy with low-dose rabeprazole, amoxicillin, and tetracycline is a good option for first-line treatment of H. pylori infection in a population with high antibiotic resistance. (This study is registered at Chinese Clinical Trials Registry [www.chictr.org.cn] under number ChiCTR1800014832.).


Asunto(s)
Amoxicilina/uso terapéutico , Bismuto/uso terapéutico , Farmacorresistencia Microbiana/efectos de los fármacos , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori/efectos de los fármacos , Rabeprazol/uso terapéutico , Tetraciclina/uso terapéutico , Adolescente , Adulto , Anciano , Antibacterianos/uso terapéutico , China , Claritromicina/uso terapéutico , Quimioterapia Combinada/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Inhibidores de la Síntesis de la Proteína/uso terapéutico , Inhibidores de la Bomba de Protones/uso terapéutico , Adulto Joven
16.
Nanotechnology ; 29(41): 412001, 2018 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-30027893

RESUMEN

A metal-free photocatalyst, graphitic carbon nitride (GCN) with a moderate band gap catering for visible-light excitation, shows amazing potential in various photocatalytic applications. Carbon dioxide reduction using diversified photocatalysts has been attracting increasing public attention and the extensively studied GCN is one of the most promising photocatalysts. However, because of the low concentration and high recombination rate of photogenerated carriers, and some other disadvantages of the pristine GCN photocatalyst, the solar-to-fuel conversion efficiency is too low for practical use. Modifications or optimizations of GCN are therefore important to enhance its CO2 photocatalytic conversion performance. This review summarizes the research progress made during the past five years on GCN-based photocatalysts in two main areas, which includes pristine GCN and its molecular modifications, and heterostructure composite photocatalysts based on GCN, for CO2 reduction. It is expected that this review may benefit the development of GCN-based photocatalysts for CO2-to-fuel conversion.

17.
Chemistry ; 23(67): 17029-17036, 2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-28976038

RESUMEN

Here we report a novel one-pot approach to synthesize MoCx catalysts at much lowered temperature for hydrogen evolution reaction (HER) in acidic solution. A room-temperature co-precipitation reaction among Ni2+ , MoO42- and 2-methylimidazole in an aqueous solution produced a Mo-Ni-imidazole complex, which was used as the precursor to fabricate MoCx . The morphological and chemical properties of the obtained MoCx affected by calcination and other additive metal sources (like Fe, Co, Cu) were investigated in detail. We demonstrated that Ni-Mo alloying took place prior to MoCx formation during heating, which catalyzed the crystallization of MoCx at relatively low temperature. The MoCx /Ni-650 catalyst exhibited a quite low overpotential of 172 mV at 20 mA cm-2 . The high performance originates from the synergistic effect between MoCx and Ni-Mo alloy, high ratio of Mo3+ /Mo2+ , as well as high electrochemically active surface area and low charge-transfer resistance. This work would open a new way to the design and fabrication of other transition-metal carbide catalysts.

18.
Chemistry ; 22(23): 7895-905, 2016 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-27106662

RESUMEN

Hierarchically structured zeolites (HSZs) have gained much academic and industrial interest owing to their multiscale pore structures and consequent excellent performances in varied chemical processes. Although a number of synthetic strategies have been developed in recent years, the scalable production of HSZs single crystals with penetrating and three-dimensionally (3-D) interconnected mesopore systems but without using a mesoscale template is still a great challenge. Herein, based on a steam-assisted crystallization (SAC) method, we report a facile and scalable strategy for the synthesis of single-crystalline ZSM-5 HSZs by using only a small amount of micropore-structure-directing agents (i.e., tetrapropylammonium hydroxide). The synthesized materials exhibited high crystallinity, a large specific surface area of 468 m(2) g(-1) , and a pore volume of 0.43 cm(3) g(-1) without sacrificing the microporosity (≈0.11 cm(3) g(-1) ) in a product batch up to 11.7 g. Further, a kinetically controlled nucleation-growth mechanism is proposed for the successful synthesis of single-crystalline ZSM-5 HSZs with this novel process. As expected, compared with the conventional microporous ZSM-5 and amorphous mesoporous Al-MCM-41 counterparts, the synthesized HSZs exhibited significantly enhanced activity and stability and prolonged lifetime in model reactions, especially when bulky molecules were involved.

19.
Med Sci Monit ; 22: 356-61, 2016 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-26835790

RESUMEN

BACKGROUND: Gastric cancer (GC) is a common malignant disease and microRNAs (miRNAs) have been shown to play important roles in GC tumorigenesis. As the clinical outcome of GC is closely correlated with the clinical stage at the time of diagnosis, early detection and prevention are crucial. This study was designed to evaluate the expression level of plasma miR-23b in patients with GC and investigate the relationship between plasma miR-23b expression level and the prognosis of GC. MATERIAL/METHODS: We recruited 138 patients diagnosed with GC and 50 healthy volunteers. Quantitative real-time PCR (qRT-PCR) was performed to evaluate the expression level of plasma miR-23b in all participants. The association between miR-23b expression and clinicopathological factors as well as survival rates was analyzed. Receiver operator curve (ROC) analysis was carried out to evaluate the diagnostic performance of plasma miR-23b for GC.Univariate and multivariate Cox regression analyses were conducted to determine whether plasma miR-23b was an independent predictor of survival. RESULTS: The expression levels of miR-23b were upregulated in plasma samples from GC patients (P<0.01) and were significantly associated with T stage, distant metastasis, and differentiation. Significantly shorter 5-year overall survival (OS) and disease-free survival (DFS) were observed in patients with higher expression of the miR-23b (P<0.01). The area under the curve (AUC) of high expression of plasma miR-23b to diagnose GC was 0.80 (95% CI: 0.74-0.86, P<0.001). Multivariate analysis revealed that enhanced expression of plasma miR-23b was an independent predictor of OS (P=0.015) and DFS (P=0.004). CONCLUSIONS: Our results indicated that plasma miR-23b was overexpressed in GC patients and high plasma miR-23b expression was associated with poor clinical outcome. Thus, plasma miR-23b may serve as a potential diagnostic biomarker and therapeutic target for GC.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , Neoplasias Gástricas/genética , Regulación hacia Arriba/genética , Anciano , Supervivencia sin Enfermedad , Femenino , Humanos , Masculino , MicroARNs/sangre , MicroARNs/metabolismo , Persona de Mediana Edad , Análisis Multivariante , Pronóstico , Sensibilidad y Especificidad , Neoplasias Gástricas/sangre , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patología
20.
Zhongguo Zhong Yao Za Zhi ; 41(18): 3361-3365, 2016 Sep.
Artículo en Zh | MEDLINE | ID: mdl-28925118

RESUMEN

The chemical constituents of the water extraction of the aerial parts of Isodon excisoides were investigated by various chromatographic methods including D-101 macroporous adsorptive resins, silica gel, Sephadex LH-20, MCI and semi-preparative HPLC. As a result, six compounds were separated and purified.By analyses of the HR-ESI-MS, 1D and 2D NMR spectra, their structures were determined as 3-O-ß-D-allopyranosyl-1-octen-3-ol(1), blumenolA (2), lumichrome (3), loliolide(4), cirsiliol(5) and pedalitin(6). Compound 1 was a new compound, and compounds 2-4 were isolated from this plant for the first time.


Asunto(s)
Isodon/química , Fitoquímicos/química , Componentes Aéreos de las Plantas/química , Estructura Molecular
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