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1.
Cardiovasc Diabetol ; 23(1): 93, 2024 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-38468331

RESUMO

BACKGROUND: Stress hyperglycemia ratio (SHR) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) are independently associated with increased mortality risk in diabetic patients with coronary artery disease (CAD). However, the role of these biomarkers in patients with diabetes and multivessel disease (MVD) remains unknown. The present study aimed to assess the relative and combined abilities of these biomarkers to predict all-cause mortality in patients with diabetes and MVD. METHODS: This study included 1148 diabetic patients with MVD who underwent coronary angiography at Tianjin Chest Hospital between January 2016 and December 2016. The patients were divided into four groups according to their SHR (SHR-L and SHR-H) and NT-proBNP (NT-proBNP-L and NT-proBNP-H) levels. The primary outcome was all-cause mortality. Multivariate Cox regression analyses were performed to evaluate the association of SHR and NT-proBNP levels with all-cause mortality. RESULTS: During a mean 4.2 year follow-up, 138 patients died. Multivariate analysis showed that SHR and NT-proBNP were strong independent predictors of all-cause mortality in diabetic patients with MVD (SHR: HR hazard ratio [2.171; 95%CI 1.566-3.008; P < 0.001; NT-proBNP: HR: 1.005; 95%CI 1.001-1.009; P = 0.009). Compared to patients in the first (SHR-L and NT-proBNP-L) group, patients in the fourth (SHR-H and NT-proBNP-H) group had the highest mortality risk (HR: 12.244; 95%CI 5.828-25.721; P < 0.001). The areas under the curve were 0.615(SHR) and 0.699(NT-proBNP) for all-cause mortality. Adding either marker to the original models significantly improved the C-statistic and integrated discrimination improvement values (all P < 0.05). Moreover, combining SHR and NT-proBNP levels into the original model provided maximal prognostic information. CONCLUSIONS: SHR and NT-proBNP independently and jointly predicted all-cause mortality in diabetic patients with MVD, suggesting that strategies to improve risk stratification in these patients should incorporate SHR and NT-porBNP into risk algorithms.


Assuntos
Doença da Artéria Coronariana , Diabetes Mellitus , Hiperglicemia , Humanos , Peptídeo Natriurético Encefálico , Doença da Artéria Coronariana/diagnóstico por imagem , Prognóstico , Biomarcadores , Fragmentos de Peptídeos , Hiperglicemia/complicações , Hiperglicemia/diagnóstico
2.
Exp Physiol ; 109(7): 1188-1198, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38774964

RESUMO

Previous studies have shown that podocyte injury is involved in the development of proteinuria in rats under hypobaric hypoxia conditions. Prolyl hydroxylase inhibitors (PHIs) may reduce proteinuria. This study aimed to further investigate whether the protective effects of hypoxia-inducible factor 1α (HIF1α) on podocyte injury induced by hypobaric hypoxia are related to Krüppel-like factor 4 (KLF4). Rats were housed in a low-pressure oxygen chamber to simulate a high-altitude environment (5000 m), and a PHI was intraperitoneally injected. Urinary protein electrophoresis was performed and the morphology of the podocytes was observed by electron microscopy. Rat podocytes were cultured under 1% O2, and siRNA was used to interfere with KLF4 expression. The protein expression levels of HIF1α, KLF4, CD2-associated protein (CD2AP) and nephrin were determined by western blotting. Compared with those in the experimental group, the rats in the intervention group on day 14 had lower urinary protein levels, increased protein expression levels of CD2AP and nephrin, and reduced podocyte injury. The results of in vitro experiments showed that the protein expression levels of KLF4, CD2AP and nephrin were greater in the PHI intervention group and lower in the HIF1α inhibitors group than in the low-oxygen group. The protein expression of CD2AP and nephrin in the siKLF4-transfected podocytes treated with PHI and HIF1α inhibitors did not differ significantly from that in the low-oxygen group. HIF1α may be involved in reducing progressive high-altitude proteinuria by regulating KLF4 expression and contributing to the repair of podocyte injury induced by hypobaric hypoxia.


Assuntos
Altitude , Subunidade alfa do Fator 1 Induzível por Hipóxia , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like , Podócitos , Ratos Sprague-Dawley , Regulação para Cima , Animais , Podócitos/metabolismo , Podócitos/patologia , Fator 4 Semelhante a Kruppel/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Masculino , Ratos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Proteinúria/metabolismo , Proteínas de Membrana/metabolismo , Proteínas do Citoesqueleto/metabolismo , Proteínas do Citoesqueleto/genética , Hipóxia/metabolismo , Proteínas Adaptadoras de Transdução de Sinal
3.
Inorg Chem ; 63(5): 2647-2654, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38262040

RESUMO

The increasing demands in optoelectronic applications have driven the advancement of organic-inorganic hybrid metal halides (OIMHs), owing to their exceptional optical and scintillation properties. Among them, zero-dimensional (0D) low-toxic manganese-based scintillators have garnered significant interest due to their exceptional optical transparency and elevated photoluminescence quantum yields (PLQYs), making them promising for colorful light-emitting diodes and X-ray imaging applications. In this study, two OIMH single crystals of (Br-PrTPP)2MnBr4 (Br-PrTPP = (3-bromopropyl) triphenylphosphonium) and (Br-BuTPP)2MnBr4 (Br-BuTPP = (4-bromobutyl) triphenylphosphonium) were prepared via a facile saturated crystallization method. Benefiting from the tetrahedrally coordinated [MnBr4]2- polyhedron, both of them exhibited strong green emissions peaked at 517 nm owing to the d-d electron transition of Mn2+ with near-unity PLQYs of 99.33 and 86.85%, respectively. Moreover, benefiting from the high optical transparencies and remarkable luminescence properties, these manganese halides also exhibit excellent radioluminescent performance with the highest light yield of up to 68,000 photons MeV-1, negligible afterglow (0.4 ms), and linear response to X-ray dose rate with the lowest detection limit of 45 nGyair s-1. In X-ray imaging, the flexible film made by the composite of (Br-PrTPP)2MnBr4 and PDMS shows an ultrahigh spatial resolution of 12.78 lp mm-1, which provides a potential visualization tool for X-ray radiography.

4.
J Nat Prod ; 87(4): 884-892, 2024 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-38408342

RESUMO

The first and stereoselective synthesis of xylodonin A and 22-hydroxyxylodonin A, two drimane-type sesquiterpenoid natural products, was developed from the readily available (+)-sclareolide. This route features an allylic oxidation and acid-promoted dehydration for construction of the key intermediate 6-hydroxyisodrimenin. Representative analogues were synthesized, and their previously unknown bioactivities were revealed after biological evaluation. The analogue 19a exhibited cytotoxic activity against liver cancer HepG2 cells (IC50: 8.8 vs 5.9 µM) that was comparable to that of the clinical anticancer drug etoposide with lower toxicity to normal liver HL7702 cells (IC50 > 100 µM).


Assuntos
Sesquiterpenos , Humanos , Estereoisomerismo , Estrutura Molecular , Células Hep G2 , Sesquiterpenos/farmacologia , Sesquiterpenos/química , Sesquiterpenos/síntese química , Ensaios de Seleção de Medicamentos Antitumorais , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/síntese química
5.
Angew Chem Int Ed Engl ; : e202412350, 2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39152766

RESUMO

Zero-dimensional (0D) hybrid metal halides have been emerged as room-temperature phosphorescence (RTP) materials, but synchronous optimization of multiple phosphorescence performance in one structural platform remains less resolved, and stable RTP activity in aqueous medium is also unrealized due to serious instability toward water and oxygen. Herein, we demonstrated a photophysical tuning strategy in a new 0D hybrid zinc halide family of (BTPP)2ZnX4 (BTPP = benzyltriphenylphosphonium, X = Cl and Br). Infrequently, the delicate combination of organic and inorganic species enables this family to display multiple ultralong green afterglow and efficient self-trapped exciton (STE) associated cyan phosphorescence. Compared with inert luminescence of [BTPP]+ cation, incorporation of anionic [ZnX4]2- effectively enhance the spin-orbit coupling effect, which significantly boosts the photoluminescence quantum yield (PLQY) up to 30.66% and 54.62% for afterglow and phosphorescence, respectively. Synchronously, the corresponding luminescence lifetime extend to 143.94 ms and 0.308 µs surpassing the indiscernible phosphorescence of [BTPP]X salt. More importantly, this halide family presents robust RTP emission with nearly unattenuated PLQY in water and harsh condition (acid and basic aqueous solution) over half a year. The highly efficient integrated afterglow and STE phosphorescence as well as ultrahigh aqueous state RTP realize multiple anti-counterfeiting applications in wide chemical environments.

6.
J Org Chem ; 88(23): 16511-16519, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37972539

RESUMO

The first synthesis of ustusal A as well as expeditious access to (-)-albrassitriol is described as featuring a singlet oxygen [4 + 2] cycloaddition, achieving the desired stereoselectivity for the 1,4-cis-hydroxyl groups. Transformation of (+)-sclareolide to III followed by a key Horner-Wadsworth-Emmons (HWE) reaction and stereospecific allylic oxidation facilitated the first synthesis of elegansin D. The biological evaluation of these natural products together with seven elegansin D analogues was performed, among which several elegansin D analogues exhibited potential anticancer activity against liver cancer HepG2 cells (IC50 = 11.99-25.58 µM) with low cytotoxicity on normal liver HL7702 cells (IC50 > 100 µM).


Assuntos
Estereoisomerismo , Oxirredução
7.
Inorg Chem ; 62(38): 15711-15718, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37695723

RESUMO

Exploring highly efficient blue-emissive lead-free halide materials is a significant and challenging objective in the study of luminescent materials. This study reports the synthesis of a new zero-dimensional (0D) hybrid zinc halide of [CYP]ZnBr4 (CYP = 1-cyclohexylpiperazine) containing an isolated [ZnBr4]2- tetrahedron. [CYP]ZnBr4 exhibits strong blue light emission with a high photoluminescence quantum yield (PLQY) of 79.22%, surpassing all previously reported 0D zinc halide counterparts. According to the theoretical and experimental studies, the blue light emission is attributed to intrinsic self-trapped excitons resulting from strong electron-phonon coupling and structural deformation. Importantly, [CYP]ZnBr4 demonstrates excellent structural and luminescence stability toward high temperatures (180 °C) over at least half a month. High luminescence efficiency and stability enable [CYP]ZnBr4 to be an efficient blue phosphor to fabricate white light-emitting diodes (LEDs), which produces high-quality white light with a color rendering index (CRI) of 93.1 and a correlated color temperature (CCT) of 5304 K, closely resembling natural sunlight. This white LED also exhibits consistent performance and stability across different drive currents, suggesting the potential for high-power optoelectronic applications. Overall, this study paves the way for the utilization of 0D hybrid halides in advanced solid-state lighting applications.

8.
Appl Opt ; 62(12): 3182-3185, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37133167

RESUMO

This paper introduces the path integral (PI) to the analysis of radially polarized (RP) beams' tight focusing problem. The PI makes the contribution of each incident ray on the focal region visible and then makes it possible to choose the filter's parameters more intuitively and precisely. Based on the PI, a zero point construction (ZPC) phase filtering method is realized intuitively. With ZPC, the focal properties of RP solid and annular beams before and after filtering were analyzed. The results show that the combination of a large NA annular beam and phase filtering can result in superior focus properties.

9.
Artigo em Inglês | MEDLINE | ID: mdl-37899211

RESUMO

BACKGROUND: The risk of low back pain (LBP) increases steeply during adolescence, and adolescents with LBP are more likely to have low back pain in their adult years. This study aimed to investigate the dose-response relationship between daily screen time and the risk of low back pain among children and adolescents. METHODS: PubMed, the Cochrane Library, Embase, and Web of Science were searched to collect relevant studies on daily screen time and the risk of low back pain from the establishment of the database up to December 2022. Two investigators independently screened the literature, extracted data, and evaluated the risk of bias in the included studies. Stata16.0 was used to perform a dose-response meta-analysis and the methodological quality evaluation of the included studies. RESULTS: The results of the meta-analysis showed that there is a positive correlation between daily computer time (OR = 1.32, 1.05-1.60), daily mobile phone time (OR = 1.32, 1.00-1.64), daily TV watching (OR = 1.07, 1.04-1.09) and the risk of low back pain, separately. The dose-response meta-analysis showed that there is a linear relationship between daily computer use and low back pain. The risk of low back pain increased by 8.2% for each 1-hour of daily computer use. CONCLUSIONS: Screen time is related to the risk of low back pain, and there is a linear relationship between daily computer use and the risk of low back pain. A number of strategic measures should be taken to prevent adolescents from developing severe low back pain.


Assuntos
Dor Lombar , Adulto , Humanos , Criança , Adolescente , Dor Lombar/epidemiologia , Dor Lombar/etiologia , Tempo de Tela
10.
Chemistry ; 28(6): e202103043, 2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-34873758

RESUMO

Mn2+ doped colloidal three-dimensional (3D) lead halide perovskite nanocrystal (PNC) has attracted intensive research attention; however, the low exciton binding energy and fatal optical instability of 3D PNC seriously hinder the optoelectronic application. Therefore, it remains significant to explore new stable host perovskite with strongly bound exciton to realize more desirable luminescent property. In this work, we utilized bulk one-dimensional (1D) hybrid perovskite of [AEP]PbBr5 ⋅ H2 O (AEP=N-aminoethylpiperazine) as structural platform to rationally optimize the luminescent property by a controllable Mn2+ doping strategy. Significantly, the series of Mn2+ -doped 1D [AEP]PbBr5 ⋅ H2 O show enhanced energy transfer efficiency from the strongly bound excitons of host material to 3d electrons of Mn2+ ions, resulting in tunable broadband light emissions from weak yellow to strong red spectral range with highest photoluminescence quantum yield up to 28.41 %. More importantly, these Mn2+ -doped 1D perovskites display ultrahigh structural and optical stabilities in humid atmosphere, water and high temperature exceeding the conventional 3D PNC. Combined highly efficient, tunable and stable broadband light emissions enable Mn2+ -doped 1D perovskite as excellent down-converting phosphor showcasing the potential application in white light emitting diode. This work not only provides a profound understanding of low-dimensional perovskites but also opens a new way to rationally design high-performance broadband light emitting perovskites for solid-state lighting and displaying devices.

11.
Nutr Metab Cardiovasc Dis ; 32(8): 1955-1962, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35752544

RESUMO

BACKGROUND AND AIMS: Type 2 diabetes mellitus (DM) accounts for more and more individuals worldwide. D-dimer has been demonstrated to be associated with cardiovascular diseases. The aim is to study the potential impact of D-dimer on the long-term prognosis of acute coronary syndrome (ACS) in the special population with type 2 DM. METHODS AND RESULTS: A total of 2265 consecutive patients with DM and ACS were eligible in the study. Patients were divided into four groups according to quartiles of D-dimer concentration. Univariate and multivariate Cox regression analysis were conducted to explore the prognostic value of D-dimer for future outcomes. Patients with higher level of D-dimer presented with higher percentage of major adverse cardiovascular events (MACEs) (23.7%), all-cause death (18.3%) and cardiovascular (CV) death (9.4%) in Quartile 4. In multivariate Cox regression analysis, D-dimer was demonstrated to be independently associated with MACEs, all-cause death and CV death. The prognostic value of D-dimer is still significant in subgroups of HbA1C <7% and ≥7%. In Kaplan-Meier analysis, higher D-dimer showed poorer prognosis in MACEs, all-cause death and CV death (all log rank p < 0.001). The area under the curve (AUC) by receiver operating characteristic (ROC) curve analysis is 0.609 for MACEs, 0.708 for all-cause death, 0.747 for CV death (p < 0.001). CONCLUSION: The present study demonstrated the independent predictive value of D-dimer for outcomes in DM patients with ACS. In addition, for the first time, we explored the prognostic value in different glucose control status.


Assuntos
Síndrome Coronariana Aguda , Diabetes Mellitus Tipo 2 , Diabetes Mellitus , Produtos de Degradação da Fibrina e do Fibrinogênio , Síndrome Coronariana Aguda/diagnóstico , Síndrome Coronariana Aguda/epidemiologia , Biomarcadores , Diabetes Mellitus/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Produtos de Degradação da Fibrina e do Fibrinogênio/química , Humanos , Prognóstico , Medição de Risco , Fatores de Risco
12.
Ann Noninvasive Electrocardiol ; 27(1): e12855, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34042244

RESUMO

The de Winter electrocardiographic (ECG) pattern was characterized by upsloping ST-segment depressions, tall and positive symmetrical T waves in precordial leads. This rare ECG pattern was recognized as an indication of proximal left anterior descending artery occlusion. Less commonly, this ECG pattern was reported in association with occlusion of other coronary artery segments. We present three cases of the de Winter pattern associated with acute total left main occlusion. This pattern may evolve to ST elevation within hours of presentation. Widespread upsloping ST-segment depressions from V2 -V6 , centered on V5 were observed in these patients.


Assuntos
Infarto do Miocárdio com Supradesnível do Segmento ST , Angiografia Coronária , Vasos Coronários , Eletrocardiografia , Humanos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico
13.
Angew Chem Int Ed Engl ; 61(35): e202206437, 2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-35670095

RESUMO

A convenient and rapid detection method for methanol in ethanol remains a major challenge due to their indistinguishable physical properties. Herein, a novel fluorescence probe based on perovskite was successfully designed to overcome this bottleneck. We report a new zero-dimensional (0D) hybrid perovskite of [MP]2 Inx Sb1-x Cl7 ⋅ 6 H2 O (MP=2-methylpiperazine) displaying an unusual green light emission with near-unity photoluminescence quantum yield. Remarkably, this 0D perovskite exhibits reversible methanol-response luminescence switching between green and yellow color but fail in any other organic vapors. Even for blended alcohol solutions, the luminescent probe exhibits excellent sensing performance with multiple superiorities of rapid response time (30 s) and ultra-low detection limit (40 ppm), etc. Therefore, this 0D perovskite can be utilized as a perfect fluorescence probe to detect traces of methanol from ethanol with ultrahigh sensitivity, selectivity and repeatability. To the best of our knowledge, this work represents the first perovskite as fluorescence probe for methanol with wide potential in environmental monitoring and methanol detection, etc.

14.
Protein Expr Purif ; 188: 105970, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34500070

RESUMO

HarpinEa protein can stimulate plants to produce defense responses to resist the attack of pathogens, improve plant immune resistance, and promote plant growth. This has extremely high application value in agriculture. To efficiently express soluble HarpinEa protein, in this study, we expressed HarpinEa protein with a 6× His-tag in Escherichia coli BL21 (DE3). Because of the low level of expression of HarpinEa protein in E. coli, three rounds of synonymous codon optimization were performed on the +53 bp of the translation initiation region (TIR) of HarpinEa. Soluble HarpinEa protein after optimization accounted for 50.3% of the total soluble cellular protein expressed. After purification using a Ni Bestarose Fast Flow column, the purity of HarpinEa protein exceeded 95%, and the yield reached 227.5 mg/L of culture medium. The purified HarpinEa protein was sensitive to proteases and exhibited thermal stability. It triggered visible hypersensitive responses after being injected into tobacco leaves for 48 h. Plants treated with HarpinEa showed obvious growth-promoting and resistance-improving performance. Thus, the use of TIR synonymous codon optimization successfully achieved the economical, efficient, and soluble production of HarpinEa protein.


Assuntos
Códon , Nicotiana/genética , Iniciação Traducional da Cadeia Peptídica , Proteínas de Plantas/genética , Mutação Silenciosa , Triticum/genética , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/metabolismo , Clonagem Molecular , Sequência Conservada , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Conformação de Ácido Nucleico , Reguladores de Crescimento de Plantas/biossíntese , Reguladores de Crescimento de Plantas/genética , Reguladores de Crescimento de Plantas/farmacologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Proteínas de Plantas/biossíntese , Proteínas de Plantas/farmacologia , Estabilidade Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologia , Solubilidade , Nicotiana/efeitos dos fármacos , Nicotiana/crescimento & desenvolvimento , Nicotiana/metabolismo , Triticum/efeitos dos fármacos , Triticum/crescimento & desenvolvimento , Triticum/metabolismo
15.
Inorg Chem ; 60(3): 1491-1498, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33464052

RESUMO

In recent years, low-dimensional lead halides have emerged as some of most attractive photoelectric materials due to their intrinsic broadband emissions with a potential application in white-light emitting diodes. To achieve the desired performance, tremendous research has emphasized the modulation of inorganic components as optical centers; however, less work has paid attention to the direct contribution of the organic components. Herein, we successfully assembled two new hybrid lead halides of [H2BPP]Pb2X6 (X = Br, 1, and Cl, 2) containing one-dimensional double [Pb2X6]2- chains using optically active 1,3-bis(4-pyridyl)-propane (BPP) as an organic cation. Under UV-light excitation, compounds 1 and 2 exhibit broadband yellowish-green emissions, which were verified by promising photoluminescence quantum efficiencies (PLQEs) of 8.10% and 4.84%, respectively. The broadband light emissions are derived from the combination of dual higher-energy blue and lower-energy yellow light spectra, which can be attributed to the individual contributions of the organic and inorganic components, respectively, according to the time-resolved and temperature-dependent emission spectra as well as theoretical calculations. This work proves the great contribution of organic components to the photophysical properties and provides a new design strategy to realize broadband light emission by rationally combining the dual-emitting properties of different assembly blocks.

16.
Inorg Chem ; 60(22): 16906-16910, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34726390

RESUMO

Herein, a new organic-inorganic hybrid cuprous iodide of [(Me)2-DABCO]Cu6I8 was prepared and structurally characterized with a novel three-dimensional (3D) [Cu6I8]2- framework. Significantly, this 3D cuprous iodide displays infrequent broadband red-to-near-infrared light emission (600-1000 nm) stemming from the radiative recombination of self-trapped excitons.

17.
Luminescence ; 36(7): 1775-1780, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34270840

RESUMO

The SrLa1-x AlO4 :xEu3+ phosphors were obtained using one calcination of a precursor synthesized using a sol-gel method. When excited at 396 nm, this phosphor emits a red light mixed with several strong peaks centred at 596 nm, 616 nm and 625 nm, attributed to 5 D0 →7 F1, 2 transitions of Eu3+ ions, respectively. The concentration quenching occurs at x = 1.5 mol% mol of SrLa1-x Eux AlO4 and the critical energy transfer distance is calculated to be 13.13 Å, the dipole-dipole interaction was found to play a role. In addition, the colour purity could be up to 97.5%. Simultaneously, the thermal stability of SrLaAlO4 :Eu3+ was measured and the thermal quenching was found at c. 275°C (T0.5 ), the excitation energy was 0.19 eV. Current results demonstrate that SrLaAlO4 :Eu3+ could be a red component candidate for white light LEDs pumped by near-UV chips.


Assuntos
Európio , Substâncias Luminescentes , Fluorescência , Luz , Luminescência
18.
Cardiovasc Diabetol ; 19(1): 80, 2020 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-32534586

RESUMO

BACKGROUND: The triglyceride-glucose index (TyG index) has been regarded as a reliable alternative marker of insulin resistance and an independent predictor of cardiovascular outcomes. Whether the TyG index predicts adverse cardiovascular events in patients with diabetes and acute coronary syndrome (ACS) remains uncertain. The aim of this study was to investigate the prognostic value of the TyG index in patients with diabetes and ACS. METHODS: A total of 2531 consecutive patients with diabetes who underwent coronary angiography for ACS were enrolled in this study. Patients were divided into tertiles according to their TyG index. The primary outcomes included the occurrence of major adverse cardiovascular events (MACEs), defined as all-cause death, non-fatal myocardial infarction and non-fatal stroke. The TyG index was calculated as the ln (fasting triglyceride level [mg/dL] × fasting glucose level [mg/dL]/2). RESULTS: The incidence of MACE increased with TyG index tertiles at a 3-year follow-up. The Kaplan-Meier curves showed significant differences in event-free survival rates among TyG index tertiles (P = 0.005). Multivariate Cox hazards regression analysis revealed that the TyG index was an independent predictor of MACE (95% CI 1.201-1.746; P < 0.001). The optimal TyG index cut-off for predicting MACE was 9.323 (sensitivity 46.0%; specificity 63.6%; area under the curve 0.560; P = 0.001). Furthermore, adding the TyG index to the prognostic model for MACE improved the C-statistic value (P = 0.010), the integrated discrimination improvement value (P = 0.001) and the net reclassification improvement value (P = 0.019). CONCLUSIONS: The TyG index predicts future MACE in patients with diabetes and ACS independently of known cardiovascular risk factors, suggesting that the TyG index may be a useful marker for risk stratification and prognosis in patients with diabetes and ACS.


Assuntos
Síndrome Coronariana Aguda/sangue , Glicemia/metabolismo , Diabetes Mellitus/sangue , Triglicerídeos/sangue , Síndrome Coronariana Aguda/diagnóstico por imagem , Síndrome Coronariana Aguda/epidemiologia , Idoso , Biomarcadores/sangue , China/epidemiologia , Angiografia Coronária , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , Progressão da Doença , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Intervalo Livre de Progressão , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo
19.
Inorg Chem ; 59(19): 14085-14092, 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-32926625

RESUMO

In recent years, two-dimensional (2D) hybrid lead halide perovskites based on corner-shared [PbX6] octahedrons have received extensive attention with important potentials in single-component white-light emitting diodes (WLEDs) due to the soft and distorted crystal lattices. However, limited research focused on the one-dimensional (1D) perovskites although they possess similar structural superiorities to achieve this performance. Herein, by using different types of organic amine cations as structural direction reagents, we report one new type of hybrid 1D perovskites of APbCl3 (A = (DTHPE)0.5, DMTHP, DBN) based on the same 1D face-shared octahedral [PbCl3]- chains. Upon UV light excitation, these 1D APbCl3 perovskites exhibit intrinsic broad-band bluish white-light emissions covering entire visible light spectra with the highest photoluminescence quantum yield (PLQY) of 6.99%, which catches up with the values of previously reported 2D perovskites. Through the systematical studies of time-resolved, temperature-dependent PL emissions, theoretical calculations, and so on, these broad-band light emissions can be ascribed to the radiative transition within conjugated organic cations. The facile assembly process, intrinsic broad-band light emissions, and high PLQYs enable these 1D APbCl3 perovskites as new types of promising candidates in fabricating single-component WLEDs.

20.
Inorg Chem ; 59(7): 4311-4319, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32202431

RESUMO

In the past few decades, organic-inorganic hybrid metal halides acting as single-component white light emission diodes (LEDs) have attracted extensive attentions, but most of the studies concentrate on the low-dimensional lead perovskites. Here, by using the nontoxic silver as optically active metal center, a series of hybrid silver halides based on one-dimensional structures were constructed and realized broadband white light emission. Compounds [H2DABCO][Ag2X4(DABCO)] (X = Br (1), I (2)) feature one-dimensional [Ag2X4(DABCO)]2- structures charged balanced by [H2DABCO]2+ cations. Compound 1 exhibits an efficient broadband white-light emission with photoluminescence quantum efficiency (PLQE) of about 2.1% and excellent photochemical stability, while compound 2 gives a broadband yellow-white emission centered at 556 nm. [HDABCO]3Ag5Cl8 (3) gives a strong broadband yellow emission (585 nm) with high PLQE of 6.7%, which can be easily fabricated as a white light emitting device. Based on the temperature-dependent, particle-size-dependent, and time-resolved PL measurements as well as other detailed studies, the broadband white-light emissions are ascribed to the synergetic effects of the organic and inorganic components. Our work provides a unique structural assembly method to explore lead-free single-component white-light illuminants from molecular level.

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