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1.
Nano Lett ; 24(9): 2765-2772, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38393855

RESUMEN

Alloying lanthanide ions (Yb3+) into perovskite quantum dots (Yb3+:CsPb(Cl1-xBrx)3) is an effective method to achieve efficient near-infrared (NIR) luminescence (>950 nm). Increasing the Yb3+ alloying ratio in the perovskite matrix enhances the luminescence intensity of Yb3+ emission at 990 nm. However, high Yb3+ alloying (>15%) results in vacancy-induced inferior material stability. In this work, we developed a polarity-mediated antisolvent manipulation strategy to resolve the incompatibility between a high Yb3+ alloying ratio and inferior stability of Yb3+:CsPb(Cl1-xBrx)3. Precise control of solution polarity enables increased uniformity of the perovskite matrix with fewer trap densities. Employing this strategy, we obtain Yb3+:CsPb(Cl1-xBrx)3 with the highest Yb3+ alloying ratio of 30.2% and a 2-fold higher electroluminescence intensity at 990 nm. We lever the engineered Yb3+:CsPb(Cl1-xBrx)3 to fabricate NIR-LEDs, achieving a peak external quantum efficiency (EQE) of 8.5% at 990 nm: this represents the highest among perovskite NIR-LEDs with an emission wavelength above 950 nm.

2.
Sci Bull (Beijing) ; 68(23): 2954-2961, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37919156

RESUMEN

In terms of tunable luminescence and high quantum efficiency, colloidal quantum dots (CQDs) are promising semiconductors for constructing near-infrared light-emitting diodes (NIR-LEDs). However, currently available NIR-LEDs are susceptible to variations in the emission layer thickness (EMLT), the highest external quantum efficiency (EQE) decreases to below 50% (relative to peak EQE) when the EMLT varies out of a narrow range of (±30 nm). This is due to the thickness-dependent carrier recombination rate and current density variation, resulting in batch-to-batch EQE fluctuations that limit LED reproducibility. Here we report efficient NIR-LEDs that exhibit EQE variations of less than 15% (relative to the champion EQE) over an EMLT range of 40-220 nm; the highest achievable EQE of ∼11.5% was obtained by encapsulating a 212 nm-thick CQD within a type-I inorganic shell to enhance the radiative recombination in the dots, resulting in a high photoluminescence quantum yield of 80%, and by post-treating the films with a bifunctional linking agent to improve and balance the hole and electron mobilities in the entire film (electron mobility: 8.23 × 10-3 cm2 V-1 s-1; hole mobility: 7.0 × 10-3 cm2 V-1 s-1). This work presents the first NIR-LEDs that exhibit EMLT-invariant EQE over an EMLT range of 40-220 nm, which represents the highest EQE among reported CQD NIR-LEDs with a QD thickness exceeding 100 nm.

3.
Angew Chem Int Ed Engl ; 62(46): e202311089, 2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-37770413

RESUMEN

Resurfacing perovskite nanocrystals (NCs) with tight-binding and conductive ligands to resolve the dynamic ligands-surface interaction is the fundamental issue for their applications in perovskite light-emitting diodes (PeLEDs). Although various types of surface ligands have been proposed, these ligands either exhibit weak Lewis acid/base interactions or need high polar solvents for dissolution and passivation, resulting in a compromise in the efficiency and stability of PeLEDs. Herein, we report a chemically reactive agent (Iodotrimethylsilane, TMIS) to address the trade-off among conductivity, solubility and passivation using all-inorganic CsPbI3 NCs. The liquid TMIS ensures good solubility in non-polar solvents and reacts with oleate ligands and produces in situ HI for surface etching and passivation, enabling strong-binding ligands on the NCs surface. We report, as a result, red PeLEDs with an external quantum efficiency (EQE) of ≈23 %, which is 11.2-fold higher than the control, and is among the highest CsPbI3 PeLEDs. We further demonstrate the universality of this ligand strategy in the pure bromide system (CsPbBr3 ), and report EQE of ≈20 % at 640, 652, and 664 nm. This represents the first demonstration of a chemically reactive ligand strategy that applies to different systems and works effectively in red PeLEDs spanning emission from pure-red to deep-red.

4.
Nanomaterials (Basel) ; 13(10)2023 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-37242111

RESUMEN

Quantum dot light-emitting diodes (QLEDs) have been identified as a next-generation display technology owing to their low-cost manufacturing, wide color gamut, and electrically driven self-emission properties. However, the efficiency and stability of blue QLEDs still pose a significant challenge, limiting their production and potential application. This review aims to analyse the factors leading to the failure of blue QLEDs and presents a roadmap to accelerate their development based on the progress made in the synthesis of II-VI (CdSe, ZnSe) quantum dots (QDs), III-V (InP) QDs, carbon dots, and perovskite QDs. The proposed analysis will include discussions on material synthesis, core-shell structures, ligand interactions, and device fabrication, providing a comprehensive overview of these materials and their development.

5.
Comput Math Methods Med ; 2022: 9380283, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36203531

RESUMEN

Background: This study is aimed at investigating whether relaxin-3 exhibits protective effects against cardiomyopathy in diabetic rats by suppressing ERS. Methods: Eighty male SD rats were randomly divided into two groups: controls (n = 20) and diabetes (n = 60). The streptozotocin-treated rats were randomly divided into three groups: diabetic group (DM), low-dose relaxin-3 group (0.2 µg/kg/d), and high-dose relaxin-3 group (2 µg/kg/d). The myocardial tissues and collagen fiber were observed by hematoxylin and eosin (H&E) and Masson staining. Serum brain natriuretic peptide (BNP), troponin (TNI), myoglobin, interleukin (IL-17), interleukin (IL)-1α, and tumor necrosis factor (TNF)-α were determined by ELISA. The protein expression of glucose regulatory protein 78 (GRP78) and C/EBP homologous protein (CHOP) in the heart tissue of each group was detected by Western blot analysis. Results: (1) HE and Masson staining indicated that relaxin-3 could attenuate myocardial lesions and myocardial collagen volume fraction. (2) BNP, TnI, and myoglobin in the DM group at four and eight weeks were significantly higher than in the controls (P < 0.01). The relaxin-3-treated groups showed significantly reduced serum BNP, TnI, and myoglobin levels compared with the DM group (P < 0.05). (3) IL-17, IL-1α, and TNF-α levels in the DM rats at 4 weeks were higher than in the controls (P < 0.05). Low or high dose of relaxin-3-treated groups showed reduced serum IL-17 and TNF-α levels compared with the DM group at four and eight weeks (P < 0.05). (4) CHOP and GRP78 protein expression was increased in the DM group at four and eight weeks compared with the controls (P < 0.01), and small and large doses of relaxin-3 significantly reduced GRP78 and CHOP protein expression. Conclusions: Exogenous relaxin-3 ameliorates diabetic cardiomyopathy by inhibiting ERS in diabetic rats.


Asunto(s)
Diabetes Mellitus Experimental , Cardiomiopatías Diabéticas , Relaxina , Animales , Apoptosis , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/metabolismo , Cardiomiopatías Diabéticas/tratamiento farmacológico , Cardiomiopatías Diabéticas/patología , Estrés del Retículo Endoplásmico , Eosina Amarillenta-(YS)/farmacología , Eosina Amarillenta-(YS)/uso terapéutico , Glucosa , Hematoxilina/farmacología , Hematoxilina/uso terapéutico , Interleucina-17/farmacología , Interleucina-17/uso terapéutico , Masculino , Mioglobina/farmacología , Mioglobina/uso terapéutico , Péptido Natriurético Encefálico/farmacología , Péptido Natriurético Encefálico/uso terapéutico , Ratas , Ratas Sprague-Dawley , Relaxina/farmacología , Relaxina/uso terapéutico , Estreptozocina/farmacología , Estreptozocina/uso terapéutico , Troponina/farmacología , Troponina/uso terapéutico , Factor de Necrosis Tumoral alfa
6.
Biomed Res Int ; 2020: 1710452, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31998781

RESUMEN

BACKGROUND: This study aims to investigate the coronary microcirculatory resistance and prognosis of patients with acute myocardial infarction (AMI) concomitant with hyperhomocysteinemia (HHcy) after an elective percutaneous coronary intervention (PCI). METHODS: A total of 101 patients that underwent elective PCI between May 2015 and July 2018 due to AMI were consecutively enrolled in this study. Patients were divided into a HHcy group (53) and a normal Hcy group (control; 48) based on their plasma homocysteine concentration. The characteristics of coronary angiography, the index of microcirculatory resistance (IMR) of infarct-related vessels (IRV), changes in left ventricular end diastolic diameter (LVEDd) and left ventricular ejection fraction (LVEF) before and after PCI, and the incidence of major adverse cardiovascular events (MACE) three months after PCI were compared between these groups. RESULTS: Compared to the results from the Hcy group, the HHcy group had a higher IMR. The HHcy group had significantly higher LVEDd and a lower LVEF than the Hcy group 3 months after PCI. Additionally, the incidence of MACE at three months after PCI was higher in the HHcy group than in the Hcy group. Pearson correlation analysis revealed a positive correlation with IMR in the HHcy group. Furthermore, there was a difference in the LVEDd measured at one day after PCI and at three months after PCI in the HHcy group. CONCLUSION: AMI patients concomitant with HHcy that undergo elective PCI are prone to coronary microcirculatory dysfunction and have a poor cardiac function and poor prognosis at three months after PCI.


Asunto(s)
Resistencia Capilar , Circulación Coronaria , Procedimientos Quirúrgicos Electivos/efectos adversos , Infarto del Miocardio , Intervención Coronaria Percutánea/efectos adversos , Complicaciones Posoperatorias , Anciano , Femenino , Humanos , Hiperhomocisteinemia/sangre , Hiperhomocisteinemia/diagnóstico , Hiperhomocisteinemia/etiología , Hiperhomocisteinemia/fisiopatología , Masculino , Persona de Mediana Edad , Infarto del Miocardio/sangre , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/cirugía , Complicaciones Posoperatorias/sangre , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/fisiopatología , Pronóstico , Factores de Tiempo
7.
Chem Commun (Camb) ; 56(7): 1038-1041, 2020 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-31850459

RESUMEN

A crown ether-appended calix[2]triazolium[2]arene, which exhibits excellent selectivity for H2PO4- compared to other anions, has been designed and synthesized. The selectivity of the prepared receptor for H2PO4- is caused by the stabilization of H2PO4- by the neighboring triazolium hydrogen bond donors and crown ether hydrogen bond acceptors.

8.
Neurol Sci ; 36(10): 1751-61, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26209930

RESUMEN

The objective of this meta-analysis was to evaluate the effects of repetitive transcranial magnetic stimulation (rTMS) for the treatment of depression in patients with Parkinson disease in order to arrive at qualitative and quantitative conclusions about the efficacy of rTMS. We included randomized controlled trials examining the effects of rTMS compared with sham-rTMS or selective serotonin re-uptake inhibitors (SSRIs). The quality of included studies was strictly evaluated. Data analyses were performed using the RevMan5.1 software. Eight studies including 312 patients met all inclusion criteria. The results showed that rTMS could evidently improve the HRSD score compared with sham-rTMS (p < 0.00001). However, we found similar antidepressant efficacy between rTMS and SSRIs groups in terms of HRSD and BDI score (p = 0.65; p = 0.75, respectively). Furthermore, patients who received rTMS could evidently show improvement on the unified Parkinson's disease rating scale (UPDRS), ADL score, and UPDRS motor score compared with sham-rTMS or SSRIs (p < 0.05, p = 0.05, respectively). The subgroup analysis by frequency of rTMS evidenced that the efficacy of low-frequency rTMS was superior to sham-rTMS (p < 0.0001) in terms of the outcome measure according to HAMD scale. Meanwhile, the high-frequency rTMS has the same antidepressant efficacy as SSRIs (p = 0.94). The current meta-analysis provided evidence that rTMS was superior to sham-rTMS and had similar antidepressant efficacy as SSRIs, and may have the additional advantage of some improvement in motor function.


Asunto(s)
Trastorno Depresivo/terapia , Enfermedad de Parkinson/terapia , Estimulación Magnética Transcraneal , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Estimulación Magnética Transcraneal/métodos
9.
Neurol Sci ; 36(6): 833-43, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25724804

RESUMEN

Numerous practice guidelines have recommended cognitive behavioral therapy (CBT) and psychodynamic therapy as a treatment of choice for depression in Parkinson's disease (PD). However, no recent meta-analysis has examined the effects of brief psychotherapy (which includes both CBT and psychodynamic therapy) for adult depression in PD. We decided to conduct such a systematic review and meta-analysis. We included randomized controlled trials (RCTs) examining the effects of brief psychotherapy compared with control groups, other support nursing, or pharmacotherapy. The quality of included studies was strictly evaluated. Twelve studies including 766 patients met all inclusion criteria. The result showed that brief psychotherapy could evidently improve the HAMD (p < 0.00001) and Moca scale (p = 0.006). There was no statistical significance in PDQ-39 scale (p = 0.31). In the subgroup analysis by types of brief psychotherapy, the efficacy of psychodynamic psychotherapy was better than CBT (SMD = -2.02 vs SMD = -0.90) for the outcome measure according to HAMD scale. Meanwhile, we found brief psychotherapy in China was more effective than in US (SMD = -1.54 vs SMD = -1.23), and in low quality studies was more efficacious than in high quality studies (SMD = -1.50 vs SMD = -1.33). Time of brief psychotherapy treatment above 6 weeks was superior to studies with less than 6 weeks treatment. We found brief psychotherapy is probable effective in the management of depression in PD patients. But one reason to undermine the validity of findings is high clinical heterogeneity and low methodological quality of the included trials.


Asunto(s)
Cognición/fisiología , Terapia Cognitivo-Conductual , Depresión/terapia , Trastorno Depresivo/terapia , Enfermedad de Parkinson/terapia , Psicoterapia Psicodinámica , Depresión/etiología , Depresión/psicología , Trastorno Depresivo/etiología , Trastorno Depresivo/psicología , Humanos , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/psicología
10.
Neurol Sci ; 35(10): 1495-504, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25027012

RESUMEN

Clinical diagnosis of Parkinson's disease (PD) is essential but misdiagnosis of PD-like diseases is quite common. LRRK2 G2385R variants have been extensively examined for the association to the risk of Parkinson's disease. However, results from different studies are inconsistent. The purpose of this meta-analysis was to assess the association between the LRRK2 G2385R variants and the risk of PD. A systematic literature search was performed for 6 databases up to January of 2014 to identify case-control studies involving LRRK2 G2385R variants and the risk of PD. A total of 12,915 cases and 12,451 controls in 23 case-control studies were included in this meta-analysis. The results indicated that the variant A allele carriers (GA + AA) increased risk of PD when compared with the homozygote GG (GA + AA vs. GG: OR = 2.4, 95 % CI = 1.97 to 2.92, P < 0.00001). In the subgroup analysis by ethnicity, increased risks were identified among Chinese (OR = 2.69, 95 % CI = 2.1-3.45, P < 0.00001) as well as in non-Chinese (OR = 2.17, 95 % CI 1.75-2.69, P < 0.00001). In the subgroup analysis by age of onset, significant associations were found in both later-onset PD (LOPD) and early-onset PD (EOPD) cases. And there was no significant difference of the allele frequency between patients with LOPD and EOPD (OR = 1.18, 95 % CI = 0.77-1.80, P = 0.45). Our results suggest that the LRRK2 G2385R variants contribute to the susceptibility of PD especially in Chinese PD. Meanwhile, it is possible that age is not the risk factor to facilitate G2385R gene mutation.


Asunto(s)
Predisposición Genética a la Enfermedad , Enfermedad de Parkinson/genética , Polimorfismo Genético , Proteínas Serina-Treonina Quinasas/genética , Estudios de Casos y Controles , Femenino , Estudios de Asociación Genética , Humanos , Proteína 2 Quinasa Serina-Treonina Rica en Repeticiones de Leucina , Masculino , Mutación , Factores de Riesgo
11.
Neurol Sci ; 35(5): 653-62, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24510151

RESUMEN

L-dopa-induced dyskinesias (LIDs) are abnormal involuntary movements (AIM) that develop with long-term L-dopa therapy for Parkinson's disease (PD). In this study, we used these tools to describe the efficacy of nicotine reduced LID in animal models of PD. Studies were identified by electronic searching of six online databases up to September of 2013 to identify preclinical trials involving nicotine for LID in animal model. Data were extracted for AIM compared with LID animals. Pre-specified subgroup analysis was carried out according to method of model, gender, anesthetic used, and species. Combined standardized mean difference (SMD) estimates and 95 % confidence intervals (CIs) were calculated using a random-effects model. Eleven studies involving 181 animals which described the effect of nicotine on LID were included in the meta-analysis. Nicotine was efficacious in reducing total AIM compared with control group (SMD -3.77, 95 % CI -5.30 to -2.23, P < 0.00001). Meanwhile, four studies showed certain effects of nicotine for improving the axial AIM (SMD -2.21, 95 % CI -4.17 to -0.24, P = 0.03); oral AIM and forelimb AIM were obvious improved in six studies in the nicotine group (SMD -3.00, 95 % CI -4.55 to -1.44, P = 0.0002; SMD -2.52, 95 % CI -3.52 to -1.53, P < 0.00001, respectively). We conclude that nicotine appears to have efficacy in animal models of LID. Large randomized clinical trials testing the effect of nicotine in PD patients with LID are warranted.


Asunto(s)
Antiparkinsonianos/efectos adversos , Discinesia Inducida por Medicamentos/tratamiento farmacológico , Estimulantes Ganglionares/farmacología , Levodopa/efectos adversos , Nicotina/farmacología , Trastornos Parkinsonianos/tratamiento farmacológico , Animales , Antiparkinsonianos/uso terapéutico , Levodopa/uso terapéutico
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