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1.
Angew Chem Int Ed Engl ; 61(42): e202210613, 2022 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-36064999

RESUMEN

Dopant-free organic hole transport materials (HTMs) remain highly desirable for stable and efficient n-i-p perovskite solar cells (pero-SCs) but rarely succeed. Here, we propose a molecular assembly strategy to overcome the limited optoelectronic properties of organic HTMs by precisely designing a linear organic small molecule BDT-DPA-F from the atomic to the molecular levels. BDT-DPA-F can assemble into a fibril network, showing an obviously improved hole mobility and decreased energy disorder. The resultant pero-SCs showed a promising efficiency of 23.12 % (certified 22.48 %), which is the highest certified value of pero-SCs with dopant-free HTMs, to date. These devices also showed a weak-dependence of efficiency on size, enabling a state-of-the-art efficiency of 22.50 % for 1-cm2 device and 20.17 % for 15.64-cm2 module. For the first time, the pero-SCs based on dopant-free HTMs realized ultralong stabilities with T80 lifetimes over 1200 h under operation or thermal aging at 85 °C.

2.
Angew Chem Int Ed Engl ; 60(49): 25878-25883, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34585471

RESUMEN

The conformational distribution and mutual interconversion of thermally activated delayed fluorescence (TADF) emitters significantly affect the exciton utilization. However, their influence on the photophysics in amorphous film states is still not known due to the lack of a suitable quantitative analysis method. Herein, we used temperature-dependent time-resolved photoluminescence spectroscopy to quantitatively measure the relative populations of the conformations of a TADF emitter for the first time. We further propose a new concept of "self-doping" for realizing high-efficiency nondoped OLEDs. Interestingly, this "compositionally" pure film actually behaves as a film with a dopant (quasi-equatorial form) in a matrix (quasi-axial form). The concentration-induced quenching that may occur at high concentrations is thus expected to be effectively relieved. The "self-doping" OLED prepared with the newly developed TADF emitter TP2P-PXZ as a neat emitting layer realizes a high maximum external quantum efficiency of 25.4 % and neglectable efficiency roll-off.

3.
Angew Chem Int Ed Engl ; 57(30): 9480-9484, 2018 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-29863299

RESUMEN

A novel molecular model of connecting electron-donating (D) and electron-withdrawing (A) moieties via a space-enough and conjugation-forbidden linkage (D-Spacer-A) is proposed to develop efficient non-doped thermally activated delayed fluorescence (TADF) emitters. 10-(4-(4-(4,6-diphenyl-1,3,5-triazin-2-yl) phenoxy) phenyl)-9,9-dimethyl-9,10-dihydroacridine (DMAC-o-TRZ) was designed and synthesized accordingly. As expected, it exhibits local excited properties in single-molecule state as D-Spacer-A molecular backbone strongly suppress the intramolecular charge-transfer (CT) transition. And intermolecular CT transition acted as the vital radiation channel for neat DMAC-o-TRZ film. As in return, the non-doped device exhibits a remarkable maximum external quantum efficiency (EQE) of 14.7 %. These results prove the feasibility of D-Spacer-A molecules to develop intermolecular CT transition TADF emitters for efficient non-doped OLEDs.

4.
Nanotechnology ; 25(14): 145601, 2014 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-24622242

RESUMEN

Integrating vertically aligned nanowires (NWs) on a functional substrate is important for the application of NWs in wafer scale assemblies and functional devices. However, vertically aligned NWs via the current epitaxial growth route can only be prepared on crystalline wafers. A convenient method is thus presented to overcome NW substrate limitations. Liquid metal is proposed to serve as a substrate for the initial growth of vertically aligned NWs. NWs could then be harvested from the growth substrate and integrated with functional substrates. Fabricated vertically aligned silicon NWs (SiNWs) were grown on molten Sn and then integrated into a flexible transparent poly(dimethylsiloxane) film to obtain a SiNW/functional substrate device. The device showed enhanced visible-light absorption ability and refreshable visible-light bactericidal activities with a bacterial reduction rate of close to 100%, indicating that growth with molten metal as a substrate could be a promising approach for extending the function and application of NWs.


Asunto(s)
Antibacterianos/química , Dimetilpolisiloxanos/química , Nanocables/química , Nanocables/microbiología , Silicio/química , Esterilización , Antibacterianos/farmacología , Biónica , Dimetilpolisiloxanos/farmacología , Escherichia coli/efectos de los fármacos , Escherichia coli/efectos de la radiación , Luz , Nanotecnología , Nanocables/ultraestructura , Silicio/farmacología , Estaño/química
5.
Nanotechnology ; 25(26): 265401, 2014 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-24920466

RESUMEN

Photoelectrochemical (PEC) cell supports a renewable method for solving current environmental and energy issues by combining solar energy collection and photocatalysis in a single semiconductor photoelectrode. However, it is still challenged by visible light photoelectrodes. The present work reports fabricating highly efficient and stable Si nanowires (SiNWs) array as visible light photoelectrodes. It involves embedding SiNWs arrays into a transparent polymer substrate to build an axial carrier collection geometry. We demonstrated that this strategy could significantly strengthen the chemical stability of SiNWs by largely reducing their surface area. Moreover, this device structure can also enhance visible light absorption efficiency through taking advantage of the highly crystalline structure of vapor-liquid-solid (VLS) grown SiNWs. Thus it can double the photodegradation ability of SiNWs.

6.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(11): 2978-82, 2013 Nov.
Artículo en Zh | MEDLINE | ID: mdl-24555364

RESUMEN

The objectives of this study are to investigate the possible occurrence status of formamide in the intercalation system, the founction of water and the molecular configurations and orientations of formamide inserted into the interlayer of kaolinite, by washing the products with acetone to eliminate the interferences due to the outersurface absorbed formamide molecules in FTIR spectrometry. The results show that the intercalated, absorbed and free formamide probably exist in the intercalation system. Free formamide is easily to be eliminated selectively by drying, whereas the absorbed formamide is removed only by washing with the proper eluting reagent. H2O also is inserted into the interlayer during the formamide molecules' intercalation, which is deintercalated after the compounds being dried. Intercalation caused blue shifts of the inner surface OH stretching bands from 3 687 to 3 692 cm(-1), and deforming bands from 911 to 906 cm(-1), the bands at 3 651 cm(-1) disappeared with a new band appearing at 3 539 cm(-1). The frequency of the Si-O bands of kaolinite was slightly shifted. These IR bands changes implied the breaking of the H-bonds between layers of kaolinite, and the formation of new H-bonds between the kaolinite and the inserting formamide molecules in the intercalation compounds. The formamide molecules intercalated were oriented with the C-N bond perpendicular or nearly perpendicular to the (001) surface of the kaolininte and formed 2 types of H-bonding with inner-surface hydroxyls and siloxane layer of the kaolinite respectively through NH2. A novel model was provided to analyse the microstructure of kaolinite-formamide intercalation compounds. The results show that computation data is in good agreement with experimental data.

7.
Am J Med Sci ; 365(2): 169-175, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36167155

RESUMEN

BACKGROUND: Th aim of this study was to analyze acute exacerbation of chronic obstructive pulmonary disease (AECOPD) readmission events and to determine whether neutrophil-to-lymphocyte ratio (NLR) and bilirubin levels were associated with readmission after discharge due to AECOPD. METHODS: A total of 170 patients with AECOPD were included. Patients were stratified into the readmission group if patients had two or more readmissions within 2 years of the previous discharge, and the non-readmission group with one readmission or none within 2 years of the last discharge. Data were collected and compared between groups. The patients were separated by the cutoffs of NLR and bilirubin level. The number of all-cause readmissions within 2 years, time to first COPD-related readmission, 1-year/2-year COPD-related readmission, 1-year/2-year all-cause mortality were compared between groups, respectively. RESULTS: Compared with the readmission group, patients of the non-readmission group had a shorter length of hospital stay, more systemic corticosteroid use, higher NLR, higher bilirubin levels, and lower eosinophils counts (p < 0.05). NLR and bilirubin levels on admission had significant association with the number of all-cause readmissions (p < 0.05). Lower bilirubin was associated with an increased risk of 1-year COPD-related readmission (OR 5.063) and 2-year COPD-related readmission (OR 4.699). CONCLUSIONS: For patients with AECOPD, longer hospital stay, and less use of systemic corticosteroids may be associated with a higher risk of readmission. NLR and bilirubin levels on admission may be related to the number of all-cause readmissions. Bilirubin can be regarded as a biomarker to predict readmission rates within 2 years after discharged throughout the course of the disease.


Asunto(s)
Neutrófilos , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Progresión de la Enfermedad , Readmisión del Paciente , Estudios Retrospectivos , Linfocitos
8.
Nanotechnology ; 23(17): 175401, 2012 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-22481573

RESUMEN

In this work, we have demonstrated that a silicon nanowire (SiNW) array can be an efficient visible light photocatalyst for hydrogen generation after being modified by the 2,9,16,23-tetraaminophthalocyanine of zinc (ZnTAPc). A photoelectrochemical (PEC) cell employing a ZnTAPc modified SiNW array as photoanode was found to be able to effectively produce hydrogen at a rate of 13 µmol (cm(2) h)(-1) under 100 mw cm(-2) irradiation from a xenon lamp. It is believed that the loading of ZnTAPc can enhance the efficiency of hydrogen generation and the stability of the SiNW array. This demonstrates that the ZnTAPc modified SiNW is a promising material for solar hydrogen generation.

9.
Chem Sci ; 13(13): 3625-3651, 2022 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-35432901

RESUMEN

Nondoped organic light-emitting diodes (OLEDs) have drawn immense attention due to their merits of process simplicity, reduced fabrication cost, etc. To realize high-performance nondoped OLEDs, all electrogenerated excitons should be fully utilized. The thermally activated delayed fluorescence (TADF) mechanism can theoretically realize 100% internal quantum efficiency (IQE) through an effective upconversion process from nonradiative triplet excitons to radiative singlet ones. Nevertheless, exciton quenching, especially related to triplet excitons, is generally very serious in TADF-based nondoped OLEDs, significantly hindering the pace of development. Enormous efforts have been devoted to alleviating the annoying exciton quenching process, and a number of TADF materials for highly efficient nondoped devices have been reported. In this review, we mainly discuss the mechanism, exciton leaking channels, and reported molecular design strategies of TADF emitters for nondoped devices. We further classify their molecular structures depending on the functional A groups and offer an outlook on their future prospects. It is anticipated that this review can entice researchers to recognize the importance of TADF-based nondoped OLEDs and provide a possible guide for their future development.

10.
Bull Cancer ; 109(6): 642-647, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34657726

RESUMEN

AIM: To investigate the therapeutic effect of Elemene combined with Nedaplatin (ECN) on malignant pleural effusion (MPE) and its adverse reactions. METHOD: A retrospective study was conducted, three hundred and fifty-two patients with MPE were divided into two groups according to different treatment methods. One hundred and eighty-nine patients were given intrathoracic injection of ECN and classified in ECN group; one hundred and sixty-three cases in the Nedaplatin group were given intrathoracic injection of nedaplatin. Routine treatments were used to prevent adverse reactions. RESULT: The effective rate of the ECN group was 57.05%, and that of the Nedaplatin group was 23.08%. The comparison results of adverse reactions between the two groups showed that there was no significant difference in leukopenia, thrombopenia, anemia, vomitting and diarrhea, fever, hepatic damage and renal damage. The level of thoracalgia in the ECN group was higher than that in the Nedaplatin group. There was no significant change in the number of CD8+ T cells between the two groups after treatment. The number of CD4+T cells in the ECN group increased after treatment was higher than the Nedaplatin group after treatment. CONCLUSION: ECN treatment can improve clinical control of MPE with no serious adverse reaction, can effectively reduce the immunosuppressive effect of nedaplatin and enhance the immune function of MPE patients which is worthy of clinical application.


Asunto(s)
Derrame Pleural Maligno , Humanos , Compuestos Organoplatinos/efectos adversos , Derrame Pleural Maligno/tratamiento farmacológico , Estudios Retrospectivos , Sesquiterpenos
11.
Langmuir ; 27(13): 7996-9, 2011 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-21651296

RESUMEN

Geometry-based adhesion arising from hierarchical surface structure enables microspheres to adhere to cells strongly, which is essential for inorganic microcapsules that function as drug delivery or diagnostic imaging agents. However, constructing a hierarchical structure on the outer shell of the products via the current microcapsule synthesis method is difficult. This work presents a novel approach to fabricating hollow microspheres with a hierarchical shell structure through the vapor-liquid-solid (VLS) process in which liquid indium droplets act as both templates for the formation of silica capsules and catalysts for the growth of hierarchical shell structure. This hierarchical shell structure offers the hollow microsphere an enhanced geometry-based adhesion. The results provide a facile method for fabricating hollow spheres and enriching their function through tailoring the geometry of their outer shells.


Asunto(s)
Indio/química , Microesferas , Dióxido de Silicio/síntesis química , Adsorción , Estructura Molecular , Tamaño de la Partícula , Porosidad , Dióxido de Silicio/química , Propiedades de Superficie , Volatilización
12.
Chem Sci ; 12(4): 1495-1502, 2020 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-34163913

RESUMEN

Thermally activated delayed fluorescence (TADF) emitters with aggregation-induced emission (AIE) features are hot candidates for non-doped organic light-emitting diodes (OLEDs), as they are highly emissive in solid states upon photoexcitation. Nevertheless, not every AIE-TADF emitter in the past had guaranteed decent efficiencies in non-doped devices, indicating that the AIE character alone does not necessarily afford ideal non-doped TADF emitters. As intermolecular electron-exchange interaction that involves long-lived triplet excitons plays a dominant role in the whole quenching process of TADF, we anticipate that it is the main reason for the different electroluminescence performances of AIE-TADF emitters. Therefore, in this work, we designed two TADF emitters SPBP-DPAC and SPBP-SPAC by modifying a reported less successful emitter BP-DPAC with extra fluorenes to increase intermolecular distances and attenuate this electron-exchange interaction. With the fluorene lock as steric hindrance, SPBP-DPAC and SPBP-SPAC exhibit significantly higher exciton utilization in non-doped films due to the suppressed concentration quenching. The non-doped OLEDs based on SPBP-DPAC and SPBP-SPAC show an excellent maximum external quantum efficiency (EQE) of 22.8% and 21.3% respectively, and what's even more promising is that ignorable roll-offs at practical brightness (e.g., 1000 and 5000 cd m-2) were realized. These results reveal that locking the phenyl rings as steric hindrance can not only enhance the molecular rigidity, but also cause immediate relief of concentration quenching, and result in significant performance improvement under non-doped conditions. Our approach proposes a feasible molecular modification strategy for AIE-TADF emitters, potentially increasing their applicability in OLEDs.

13.
Int Immunopharmacol ; 9(1): 70-9, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18976720

RESUMEN

OBJECTIVE: Abnormal angiogenesis is a central hallmark for the development and progression of idiopathic pulmonary fibrosis. It has been shown that vascular endothelial growth factor (VEGF) is one of the critical angiogenic factors in angiogenesis. The aim of the present study was to assess whether disruption of VEGF pathway would attenuate bleomycin-induced pulmonary fibrosis. METHODS: Bleomycin-induced pulmonary fibrosis mice were treated intraperitoneally with VEGF receptor tyrosine kinase inhibitor SU5416 at different phases after bleomycin infusion. We measured angiogenesis and inflammatory response in both bleomycin-treated and control mice, and correlated these levels with pulmonary fibrosis. RESULTS: The increased expressions of VEGF/VEGFR (Flk-1) were correlated to a larger number of microvessels and a higher score of pulmonary fibrosis. Early administration of SU5416 inhibited pulmonary collagen deposition, histopathologic fibroplasias and the activation of TGF-beta1/Smad3 signaling pathway in bleomycin-stimulated lung. These were also paralleled by a reduction of VEGF/VEGFR-2 (Flk-1) expression and microvessel numbers in lung. Furthermore, SU5416 inhibited inflammatory cell numbers and LDH activity in BALF and IL-13 expression in lung tissue at early inflammatory phase of bleomycin-induced pulmonary fibrosis. CONCLUSION: These results suggest that the VEGFR-2 inhibitor, SU5416, attenuates histopathologic fibroplasias and collagen deposition by regulating angiogenesis and inflammation in the lung.


Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Antibióticos Antineoplásicos/antagonistas & inhibidores , Antibióticos Antineoplásicos/toxicidad , Bleomicina/antagonistas & inhibidores , Bleomicina/toxicidad , Indoles/farmacología , Fibrosis Pulmonar/inducido químicamente , Fibrosis Pulmonar/prevención & control , Pirroles/farmacología , Receptor 2 de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Animales , Western Blotting , Líquido del Lavado Bronquioalveolar/citología , Citometría de Flujo , Hidroxiprolina/metabolismo , Pulmón/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Neovascularización Patológica/patología , Neovascularización Patológica/prevención & control , Fibrosis Pulmonar/patología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal/efectos de los fármacos , Proteína smad3/biosíntesis , Proteína smad3/genética , Factor de Crecimiento Transformador beta1/biosíntesis , Factor de Crecimiento Transformador beta1/genética , Factor A de Crecimiento Endotelial Vascular/biosíntesis
14.
Respirology ; 14(5): 734-45, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19659652

RESUMEN

BACKGROUND AND OBJECTIVE: The aim of this study was to assess the beneficial effects of simvastatin on cigarette smoke-induced small airway remodeling in rats. METHODS: Simvastatin was administered at different doses for 16 weeks to rats with cigarette smoke-induced small airway remodelling. Morphological analyses were performed, and collagen deposition, production of growth factors, inflammatory parameters and RhoA, as well as the Smad signalling pathway in the lungs, were examined. RESULTS: Simvastatin attenuated small airway wall thickening and prevented the increase in lung hydroxyproline content and collagen deposition induced in airway walls by cigarette smoking. In addition, simvastatin downregulated transforming growth factor-beta1 and connective tissue growth factor protein and gene expression in the lungs. Furthermore, accumulation of macrophages and neutrophils and increases in tumour necrosis factor-alpha concentration in BAL fluid were inhibited by simvastatin. Simultaneously, the expression of RhoA and the phosphorylation of Smad2 and Smad3 in lungs exposed to cigarette smoke were inhibited during simvastatin administration. However, the increased expression of Smad2 and Smad3 proteins and the decreased level of Smad7 protein in remodelled lungs were not affected by simvastatin. CONCLUSIONS: Simvastatin attenuated experimental small airway remodelling, as indicated by decreases in collagen deposition and small airway wall thickening. Simvastatin may inhibit cigarette smoke-induced small airway remodelling by reducing growth factor expression and inflammation. The mechanism of action of simvastatin on small airway remodelling involved RhoA and the Smad signalling pathway. These findings indicate that simvastatin may have potential beneficial effects in the treatment of COPD.


Asunto(s)
Remodelación de las Vías Aéreas (Respiratorias)/efectos de los fármacos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Simvastatina/farmacología , Contaminación por Humo de Tabaco/efectos adversos , Animales , Colágeno/metabolismo , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Hidroxiprolina/metabolismo , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Pulmón/patología , Masculino , Ratas , Ratas Sprague-Dawley , Transducción de Señal/fisiología , Proteínas Smad/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Proteína de Unión al GTP rhoA/metabolismo
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(8): 2067-70, 2009 Aug.
Artículo en Zh | MEDLINE | ID: mdl-19839309

RESUMEN

Benzamide was intercalated into kaolinite by replacing DMSO pre-intercalated. Pure kaolinite-benzamide intercalation compounds were obtained by washing resulting products with acetone. The analysis of XRD shows that the basal spacing of kaolinite-benzamide intercalation compounds increased to 1.437 nm from 0.717 nm of kaolinite. The analysis of FTIR shows that intercalation caused the shifts of the inner surface OH stretching bands from 3 696 and 3 657 cm(-1) of the raw kaolinite to 3 701 and 3 651 cm(-1) of the kaolinite-benzamide intercalation compounds, respectively, and the blue shift of C=O stretching bands from 1 659 cm(-1) of benzamdie to 1 640 cm(-1) of the kaolinite-benzamide intercalation compounds, and the NH vibrations at 3 368 and 3 172 cm(-1) of benzamdie shifted to 3 474 and 3 184 cm(-1), respectively. These changes in IR bands implied the breaking of the H-bonds between layers of kaolinite and the formation of new H-bonds between the inner-surface hydroxyls of the kaolinite and the benzamide in the intercalation compounds. The experimental results show that the intercalation reaction comes to equilibrium rapidly during 30 min, and the highest intercalation ratio occurs when the reaction temperature is 180 degrees C. Washed by acetone, the residual benzamide and that adsorbed on the surface of the resulting products could be eliminated without significant influence on the structure of the intercalation compounds.

16.
Int J Chron Obstruct Pulmon Dis ; 14: 2725-2731, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31819404

RESUMEN

Purpose: The current guidelines recommend the use of systemic corticosteroids (SCS) as the optimal treatment for acute exacerbations of chronic obstructive pulmonary disease (AECOPD). The aim of this real-world study was to evaluate whether nebulized budesonide (NBS) could also be used as an initial treatment for AECOPD. Patients and methods: AECOPD patients initially treated with NBS or SCS (oral/intravenous) were enrolled. A large-scale, long-term multicenter cohort study of AECOPD patients was performed to analyze outcomes for each treatment (NCT02051166). Results: Initial NBS and SCS treatment resulted in similar outcomes in terms of improvements in FEV1, PaO2, SaO2, and PaCO2. Disease severity affected outcome similarly in both groups. When the groups were stratified according to whether the initial treatment was subsequently intensified or reduced, more intubation was seen in the groups in which initial treatment was intensified. NBS escalation and SCS reduction groups spent more days in the hospital. The NBS escalation group was associated with the highest medical expenditure and a relatively higher rate of new-onset pneumonia. The NBS maintenance/reduction group showed the lowest mortality rate between groups. Stratification according to initial PaCO2 level showed more intubation in the groups with high initial PaCO2 concentrations. Conclusion: These results indicate that NBS may be used as an initial treatment in certain AECOPD patients, and further studies are needed to better define those most likely to benefit.


Asunto(s)
Broncodilatadores/administración & dosificación , Budesonida/administración & dosificación , Glucocorticoides/administración & dosificación , Pulmón/efectos de los fármacos , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Administración por Inhalación , Anciano , Anciano de 80 o más Años , Broncodilatadores/efectos adversos , Budesonida/efectos adversos , China , Progresión de la Enfermedad , Femenino , Volumen Espiratorio Forzado , Glucocorticoides/efectos adversos , Humanos , Pulmón/fisiopatología , Masculino , Persona de Mediana Edad , Nebulizadores y Vaporizadores , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Recuperación de la Función , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento
17.
ACS Appl Mater Interfaces ; 11(14): 13472-13480, 2019 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-30892014

RESUMEN

Two novel thermally activated delayed fluorescence (TADF) emitters, 3-phenylquinolino[3,2,1- de]acridine-5,9-dione (3-PhQAD) and 7-phenylquinolino[3,2,1- de]acridine-5,9-dione (7-PhQAD), were designed and synthesized based on a rigid quinolino[3,2,1- de]acridine-5,9-dione (QAD) framework. With the effective superimposed resonance effect from electron-deficient carbonyls and electron-rich nitrogen atom, both emitters realize significant TADF characteristics with small Δ ESTs of 0.18 and 0.19 eV, respectively. And, molecular relaxations were dramatically suppressed for both emitters because of their conjugated structure. In the devices, 3-PhQAD realizes superior performance with a maximum external quantum efficiency (EQE) of 19.1% and a narrow full width at half-maximum (FWHM) of 44 nm, whereas a maximum EQE of 18.7% and an extremely narrow FWHM of 34 nm are realized for 7-PhQAD. These superior results reveal that apart from nitrogen and boron-aromatic systems, QAD framework can also act as a TADF matrix with effective resonance effect, and QAD derivatives are ideal candidates to develop TADF emitters with narrow FWHMs for practical applications.

18.
Respirology ; 13(1): 63-72, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18197913

RESUMEN

BACKGROUND AND OBJECTIVE: To examine the effect of a 14-membered ring macrolide on airway mucus hypersecretion in rats treated with LPS. METHODS: Mucus hypersecretion in rat airways was induced by intratracheal instillation of LPS. Rats treated with or without LPS were administered roxithromycin (1-10 mg/kg), josamycin (10 mg/kg) or amoxicillin (40 mg/kg), orally for 4 days. Expression of Muc5ac, nuclear factor (NF)-kappaB, and the mitogen-activated protein (MAP) kinases p38 and ERK1/2 in bronchial epithelium were detected by RT-PCR, immunohistochemistry or western blotting. Mucins, IL-1beta, IL-8 and tumour necrosis factor (TNF)-alpha in BAL fluid were assayed by enzyme-linked lectin assay and ELISA. RESULTS: LPS significantly induced the expression of Muc5ac mRNA and protein in bronchial epithelium, increased the release of mucins, IL-1beta, IL-8 and TNF-alpha, and increased neutrophil numbers in BAL. Moreover, LPS increased staining for NF-kappaB in the cytoplasm as well as nuclear translocation of NF-kappaB in airway epithelial cells. Upregulated expression of Muc5ac mRNA correlated positively with NF-kappaB activation and the levels of cytokines (P < 0.05). Roxithromycin (5 and 10 mg/kg) significantly attenuated bronchial Muc5ac expression and NF-kappaB nuclear translocation stimulated by LPS, and reduced neutrophil numbers, mucins and inflammatory cytokines in BAL (P < 0.05). However, LPS-stimulated expression of p38 and ERK1/2 in airway epithelium was not affected by roxithromycin. Josamycin and amoxicillin had no effects on Muc5ac expression, NF-kappaB activation or cytokine release. CONCLUSIONS: Roxithromycin inhibits the pulmonary inflammatory response and airway mucus hypersecretion induced by LPS. The inhibitory effect of roxithromycin on airway mucus hypersecretion may be mediated through reduction of NF-kappaB activation, neutrophil infiltration and release of inflammatory cytokines in the lung.


Asunto(s)
Antibacterianos/farmacología , Josamicina/farmacología , Moco/metabolismo , Mucosa Respiratoria/efectos de los fármacos , Mucosa Respiratoria/metabolismo , Roxitromicina/farmacología , Amoxicilina/farmacología , Animales , Lipopolisacáridos , Masculino , Mucina 5AC , Mucinas/genética , Mucinas/metabolismo , FN-kappa B/efectos de los fármacos , FN-kappa B/metabolismo , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley
19.
Chin Med J (Engl) ; 121(17): 1680-7, 2008 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-19024099

RESUMEN

BACKGROUND: Mucus hypersecretion in the respiratory tract and goblet cell metaplasia in the airway epithelium contribute to the morbidity and mortality associated with airway inflammatory diseases. This study aimed to examine the effect and mechanisms of simvastatin on airway mucus hypersecretion in rats treated with lipopolysaccharide (LPS). METHODS: Mucus hypersecretion in rat airways was induced by intra-tracheal instillation of LPS. Rats treated with or without LPS were administered intra-peritoneally simvastatin (5 and 20 mg/kg) for 4 days. Expression of Muc5ac, RhoA and mitogen-activated protein kinases (MAPK) p38 in lung were detected by real-time polymerase chain reaction (PCR), immunohistochemistry or Western blotting. Tumor necrosis factor (TNF)-alpha and IL-8 in bronchoalveolar lavage fluid (BALF) were assayed by an enzyme-linked lectin assay and enzyme linked immunosorbent assay (ELISA). RESULTS: Simvastatin attenuated LPS-induced goblet cell hyperplasia in bronchial epithelium and Muc5ac hypersecretion at both the gene and protein levels in lung (P <0.05). Moreover, simvastatin inhibited neutrophil accumulation and the increased concentration of TNF-alpha and IL-8 in BALF follows LPS stimulation (P < 0.05). The higher dose of simvastatin was associated with a more significant reduction in Muc5ac mRNA expression, neutrophil accumulation and inflammatory cytokine release. Simultaneously, the increased expression of RhoA and p38 MAPK were observed in LPS-treated lung (P <0.05). Simvastatin inhibited the expression of RhoA and p38 phosphorylation in lung following LPS stimulation (P < 0.05). However, the increased expression of p38 protein in LPS-treated lung was not affected by simvastatin administration. CONCLUSIONS: Simvastatin attenuates airway mucus hypersecretion and pulmonary inflammatory damage induced by LPS. The inhibitory effect of simvastatin on airway mucus hypersecretion may be through, at least in part, the suppression of neutrophil accumulation and inflammatory cytokine release via inactivation of RhoA and p38 signaling pathway.


Asunto(s)
Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Lipopolisacáridos/toxicidad , Mucosa Respiratoria/efectos de los fármacos , Simvastatina/farmacología , Animales , Masculino , Mucina 5AC/metabolismo , Ratas , Ratas Sprague-Dawley , Mucosa Respiratoria/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Proteína de Unión al GTP rhoA/antagonistas & inhibidores
20.
Chin Med J (Engl) ; 121(18): 1821-9, 2008 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-19080365

RESUMEN

BACKGROUND: Bleomycin-induced fibrosis is extensively used to model aspects of the pathogenesis of interstitial pulmonary fibrosis. This study aimed to determine the benefic effects and mechanisms of simvastatin on bleomycin-induced pulmonary fibrosis in mice. METHODS: Bleomycin-induced pulmonary fibrosis mice were administered with simvastatin in different doses for 28 days. We measured inflammatory response, fibrogenic cytokines and profibrogenic markers in both bleomycin-stimulated and control lungs, and correlated these parameters with pulmonary fibrosis. RESULTS: Simvastatin attenuated the histopathological change of bleomycin-induced pulmonary fibrosis and prevented the increase of lung hydroxyproline content and collagen (I and III) mRNA expression induced by bleomycin. Moreover, simvastatin down-regulated the increased expression of transforming growth factor-beta1 (TGF-beta1) and connective tissue growth factor (CTGF) induced by bleomycin at both gene and protein levels. Simultaneously, the accumulation of neutrophils and lymphocytes and the increased production of tumor necrosis factor-alpha (TNF-alpha) in bronchial alveolar lavage fluid were inhibited by simvastatin in early inflammatory phase after bleomycin infusion. The higher dose of simvastatin was associated with a more significant reduction in these inflammatory and fibrotic parameters. Furthermore, the inactivation of p38, RhoA and Smad2/3 signaling pathways was observed during simvastatin administration. CONCLUSIONS: Simvastatin attenuated bleomycin-induced pulmonary fibrosis, as indicated by decreases in Ashcroft score and lung collagen accumulation. The inhibitory effect of simvastatin on the progression of pulmonary fibrosis may be demonstrated by reducing inflammatory response and production of TGF-beta1 and CTGF. These findings indicate that simvastatin may be used in the treatment of pulmonary fibrosis.


Asunto(s)
Antibióticos Antineoplásicos , Bleomicina , Fibrosis Pulmonar/inducido químicamente , Simvastatina/farmacología , Animales , Ratones , Ratones Endogámicos C57BL , Fibrosis Pulmonar/metabolismo , Fibrosis Pulmonar/patología
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