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2.
Ophthalmic Epidemiol ; 30(3): 230-238, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-35796414

RESUMO

PURPOSE: Vascular endothelial growth factor (VEGF) has obvious clinical value in diabetes, but the conclusions on the diagnostic value of diabetic retinopathy (DR) are not consistent. This study aims to comprehensively evaluate the accuracy of circulating VEGF in the diagnosis of DR in the Asian population by a method of meta-analysis. METHODS: PubMed, Cochrane Library, Embase, Web of Science, China National Knowledge Infrastructure (CNKI), and China Wanfang Databases were searched for relevant studies on the diagnostic value of VEGF for DR in Asia up to November 2021. The pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and areas under the curve (AUC) were calculated by Stata 15.0 software. RESULTS: After screening, eight eligible studies were enrolled, including 547 patients with DR. The results of the meta-analysis showed that the pooled DOR, sensitivity, specificity, PLR, and NLR were 31.67 (95%CI: 13.55 ~ 74.05), 0.86 (95%CI: 0.74 ~ 0.93), 0.84 (95%CI: 0.80 ~ 0.87), 5.33 (95%CI: 4.09 ~ 6.93), 0.17 (95%CI: 0.09 ~ 0.32), respectively. The AUC was 0.86 (95%CI: 0.82 ~ 0.89). CONCLUSION: Circulating VEGF has a good diagnostic value in DR in the Asian population, with the potential to be an early diagnostic marker for DR.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Humanos , Ásia , Sensibilidade e Especificidade , Fator A de Crescimento do Endotélio Vascular , Povo Asiático
3.
Adv Mater ; 34(26): e2201315, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35435280

RESUMO

Perovskite/silicon tandem solar cells are promising to penetrate photovoltaic market. However, the wide-bandgap perovskite absorbers used in top-cell often suffer severe phase segregation under illumination, which restricts the operation lifetime of tandem solar cells. Here, a strain modulation strategy to fabricate light-stable perovskite/silicon tandem solar cells is reported. By employing adenosine triphosphate, the residual tensile strain in the wide-bandgap perovskite absorber is successfully converted to compressive strain, which mitigates light-induced ion migration and phase segregation. Based on the wide-bandgap perovskite with compressive strain, single-junction solar cells with the n-i-p layout yield a power conversion efficiency (PCE) of 20.53% with the smallest voltage deficits of 440 mV. These cells also maintain 83.60% of initial PCE after 2500 h operation at the maximum power point. Finally, these top cells are integrated with silicon bottom cells in a monolithic tandem device, which achieves a PCE of 26.95% and improved light stability at open-circuit.

4.
J Control Release ; 318: 197-209, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31672622

RESUMO

With the in-depth research of organelles, the microenvironment characteristics of their own, such as the acid environment of lysosomes and the high temperature environment of mitochondria, could be used as a natural and powerful condition for tumor therapy. Based on this, we constructed a two-step precise targeting nanoplatform which can realize the drug release and drug action triggered by the microenvironment of lysosomes (endosomes) and mitochondria, respectively. To begin with, the mesoporous silica nanoparticles (MSNs) were modified with triphenylphosphonium (TPP) and loaded with 2,2'-azobis[2-(2-imidazolin-2-yl) propane] dihydrochloride (AIPH). Then, folic acid (FA) targeted pH-sensitive liposomes containing docetaxel (Lipo/DTX-FA) were prepared by thin-film dispersion method, and the core-shell AIPH/MSN-TPP@Lipo/DTX-FA nanoparticles were constructed by self-assembly during the hydration of the liposomes. When this nanoplatform entered into the tumor cells through FA receptor-mediated endocytosis, the pH-sensitive liposomes were destabilized in the lysosomes, resulting in the release of DTX and AIPH/MSN-TPP nanoparticles. After that, AIPH was delivered to mitochondria by AIPH/MSN-TPP, and the alkyl radicals produced by AIPH under the high temperature environment can cause oxidative damage to mitochondria. Not only that, the DTX could enhance the anti-tumor effect of AIPH by downregulating the expression of anti-apoptotic Bcl-2 protein. The in vitro and in vivo results demonstrate that this delivery system could induce apoptosis based on organelles' s own microenvironment, which provides a new approach for tumor therapy.


Assuntos
Antineoplásicos , Nanopartículas , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Docetaxel/metabolismo , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Mitocôndrias/metabolismo , Dióxido de Silício/metabolismo
5.
Nanoscale ; 11(34): 15958-15970, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31418432

RESUMO

Oral drug delivery systems (ODDSs) have attracted considerable attention in relation to orthotopic colon cancer therapy due to certain popular advantages. Unfortunately, their clinical applications are generally limited by the side-effects caused by systemic drug exposure and poor real-time monitoring capabilities. Inspired by the characteristics of pH changes of the gastrointestinal tract (GIT) and specific enzymes secreted by the colonic microflora, we anchored polyacrylic acid (PAA) and chitosan (CS) on Gd3+-doped mesoporous hydroxyapatite nanoparticles (Gd-MHAp NPs) to realize programmed drug release and magnetic resonance imaging (MRI) at the tumor sites. In particular, the grafted PAA, as a pH-responsive switch, could effect controlled drug release in the colon. Further, CS is functionalized as the enzyme-sensitive moiety, which could be degraded by ß-glycosidase in the colon. Gadolinium is a paramagnetic lanthanide element used in chelates, working as a contrast medium agent for an MRI system. Interestingly, after oral administration, CS and PAA could protect the drug-loaded nanoparticles (NPs) against variable physiological conditions in the GIT, allowing the drug to reach the colon tumor sites, preventing premature drug release. Enhanced drug concentrations at the colon tumor sites were achieved via this programmed drug release, which subsequently ameliorated the therapeutic effect. In addition, encapsulating both chemotherapeutic (5-fluorouracil, 5-FU) and targeted therapy drug (gefitinib, Gef) within Gd-MHAp NPs produced a synergistic therapeutic effect. In summary, this study demonstrated that such a novel drug system (Gd-MHAp/5-FU/Gef/CS/PAA NPs) could protect, transport, and program drug release locally within the colonic environment; further, this system exhibited a worthwhile therapeutic effect, providing a promising novel treatment strategy for orthotopic colon cancer.


Assuntos
Neoplasias do Colo , Meios de Contraste , Fluoruracila , Gadolínio , Gefitinibe , Imageamento por Ressonância Magnética , Nanopartículas , Resinas Acrílicas/química , Resinas Acrílicas/farmacocinética , Resinas Acrílicas/farmacologia , Administração Oral , Animais , Quitosana/química , Quitosana/farmacocinética , Quitosana/farmacologia , Neoplasias do Colo/diagnóstico por imagem , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Meios de Contraste/química , Meios de Contraste/farmacocinética , Meios de Contraste/farmacologia , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/farmacologia , Durapatita/química , Durapatita/farmacocinética , Durapatita/farmacologia , Fluoruracila/química , Fluoruracila/farmacocinética , Fluoruracila/farmacologia , Gadolínio/química , Gadolínio/farmacocinética , Gadolínio/farmacologia , Gefitinibe/química , Gefitinibe/farmacocinética , Gefitinibe/farmacologia , Células HT29 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/química , Nanopartículas/uso terapêutico
6.
Adv Healthc Mater ; 7(22): e1800819, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30303621

RESUMO

Sonodynamic therapy (SDT) always causes tumor hypoxia aggravation which can induce malignant cell proliferation and drug resistance. To overcome these disadvantages, a cascaded drug delivery system (Lipo/HMME/ACF@MnO2 -AS1411) is constructed for synergistic enhanced sonodynamic therapy. First, hematoporphyrin monomethyl ether (HMME) and acriflavine (ACF) are encapsulated in the lipid layers and the inner aqueous cores of the liposomes, respectively. Then the ultrathin manganese dioxide (MnO2 ) nanosheets are coated on the surface of the liposomes by using KMnO4 and polyethylene glycol through "one step reduction and modification" method. Furthermore, the nanoparticles are decorated with tumor-targeting AS1411 aptamer through the phosphate groups on the DNA strand which can bind to Mn sites to obtain Lipo/HMME/ACF@MnO2 -AS1411 delivery system. Herein, HMME can act as a sonosensitizer, and ACF is used to prevent the formation of HIF-1α/HIF-1ß dimerization to overcome the negative effects after SDT. The Lipo/HMME/ACF@MnO2 -AS1411 delivery system has multiple functions, including codelivery of HMME and ACF, pH/glutathione/ultrasound triple responses, synergistic cascaded enhancement of SDT, precise tumor-targeting, and magnetic resonance imaging. The in vitro and in vivo results suggest that the Lipo/HMME/ACF@MnO2 -AS1411 delivery system is a promising core-shell nanoplatform for synergistic enhancement of sonodynamic therapy, which can provide a new approach in the related research fields.


Assuntos
Lipossomos/química , Nanoestruturas/química , Neoplasias/terapia , Terapia por Ultrassom , Animais , Apoptose/efeitos dos fármacos , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/farmacologia , Aptâmeros de Nucleotídeos/uso terapêutico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Glutationa/química , Hematoporfirinas/química , Humanos , Concentração de Íons de Hidrogênio , Imageamento por Ressonância Magnética , Compostos de Manganês/química , Camundongos , Camundongos Nus , Nanoestruturas/uso terapêutico , Nanoestruturas/toxicidade , Óxidos/química , Sonicação , Distribuição Tecidual , Transplante Heterólogo
7.
Acta Biomater ; 62: 293-305, 2017 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-28842332

RESUMO

Amorphous biodegradable metal phosphate nanomaterials are considered to possess great potential in cancer theranostic application due to their promise in providing ultra-sensitive pH-responsive therapeutic benefits and diagnostic functions simultaneously. Here we report the synthesis of photosensitising and acriflavine-carrying amorphous porous manganese phosphate (PMP) nanoparticles with ultra-sensitive pH-responsive degradability and their application for a photoactivable synergistic nanosystem that imparts reactive oxygen species (ROS) induced cytotoxicity in synchrony with hypoxia-inducible factor 1α/vascular endothelial growth factor (HIF1α/VEGF) inhibitor that suppresses tumor growth and treatment escape signalling pathway. Carboxymethyl dextran (CMD) is chemically anchored on the surface of porous manganese phosphate theranostic system through the pH-responsive boronate esters. Upon the stimulus of the tumor acid microenvironment, manganese phosphate disintegrates and releases Mn2+ ions rapidly, which are responsible for the magnetic resonance imaging (MRI) effect. Meanwhile, the released photosensitizer chlorin e6 (Ce6) produces ROS under irradiation while acriflavine (ACF) inhibits the HIF-1α/VEGF pathway during the burst release of VEGF in tumour induced by photodynamic therapy (PDT), resulting in increased therapeutic efficacy. Considering the strong pH responsivity, MRI signal amplification and drug release profile, the PMP nanoparticles offer new prospects for tumor acidity-activatable theranostic application by amplifying the PDT through inhibiting the HIF-1α /VEGF pathway timely while enhancing the MRI effect. STATEMENT OF SIGNIFICANCE: In this study, we report the synthesis of the tumor acidity-activatable amorphous porous manganese phosphate nanoparticles and their application for a photoactivable synergistic nanosystem that imparts reactive oxygen species (ROS) induced cytotoxicity in synchrony with hypoxia-inducible factor 1α/vascular endothelial growth factor (HIF-1α/VEGF) inhibitor that suppresses tumor growth and treatment escape signalling pathway. Besides, upon the stimulus of the tumor acid microenvironment, the manganese phosphate nanoparticles finally disintegrate and release Mn2+ ions rapidly, which are responsible for the magnetic resonance imaging (MRI) effect. This nanoplatform is featured with distinctive advantages such as ultra pH-responsive drug release, MRI function and rational drug combination exploiting the blockage of the treatment escape signalling pathway.


Assuntos
Meios de Contraste , Nanopartículas , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Compostos Organometálicos , Fotoquimioterapia , Porfirinas , Animais , Linhagem Celular Tumoral , Clorofilídeos , Meios de Contraste/química , Meios de Contraste/farmacocinética , Meios de Contraste/farmacologia , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/farmacologia , Humanos , Imageamento por Ressonância Magnética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/química , Nanopartículas/uso terapêutico , Neoplasias/metabolismo , Neoplasias/patologia , Compostos Organometálicos/química , Compostos Organometálicos/farmacocinética , Compostos Organometálicos/farmacologia , Porfirinas/química , Porfirinas/farmacocinética , Porfirinas/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
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