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1.
Sci Rep ; 13(1): 4391, 2023 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-36927741

RESUMO

We aimed to evaluate the impact of new Murray law-based QFR of jailed left circumflex coronary artery (LCx) on long-term clinical outcomes after left main coronary artery (LM) simple crossover stenting. 164 patients who underwent LM-to-left anterior descending coronary artery simple crossover stenting and had appropriate angiographic view of LCx for QFR computation were enrolled. The primary clinical outcome was the 5-year target lesion failure (TLF), defined as a composite of cardiac death, a target vessel myocardial infarction or target lesion repeat revascularization. The mean QFR of the LCx after LM stent implantation was 0.88 ± 0.09, and 29 patients (17.7%) had a low QFR (< 0.80), which was significantly associated with a higher 5-year rate of TLF when compared with the high QFR group (27.6% vs. 6.7%; HR: 4.235; 95% CI 1.21-14.95; p = 0.0015). The 5-year LCx ostium-related TLR rate in the low QFR group was also higher (17.2% vs. 3.0% in the high QFR group; HR: 6.07, 95% CI 1.63-22.59, p = 0.002). In a multivariate Cox regression analysis, a low QFR in the LCx after LM stenting was an independent predictor of the 5-year TLF rate (HR: 3.21, 95% CI 1.21-8.53; p = 0.019). ROC analysis showed that QFR a negative predictive value (NPV) of 89.6% ([AUC] 0.73, 95% CI 0.58-0.88, p < 0.05), the cutoff point is 0.85. The patients with a low QFR (< 0.80) in jailed LCX after LM simple crossover stenting had worse 5-year outcomes than those with a high QFR. Conversely, a QFR ≥ 0.85 of jailed LCx could serve as a good predictor of low risk of adverse outcome in LCx ostium. The QFR computation of the jailed LCx may be helpful to determine whether an additional procedure is required for the jailed side branch.


Assuntos
Doença da Artéria Coronariana , Stents Farmacológicos , Intervenção Coronária Percutânea , Humanos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/cirurgia , Doença da Artéria Coronariana/etiologia , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/cirurgia , Vasos Coronários/patologia , Prognóstico , Angiografia Coronária/métodos , Stents Farmacológicos/efeitos adversos , Resultado do Tratamento , Stents/efeitos adversos , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/métodos , Estudos Retrospectivos
2.
Chin J Integr Med ; 28(8): 753-761, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35507299

RESUMO

Nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) is an intracellular sensor that detects endogenous danger signals and environmental irritants to assemble into the NLRP3 inflammasome. Activation of the NLRP3 inflammasome leads to the secretion of the proinflammatory cytokines interleutkin (IL)-1ß and IL-18 and induces pyroptosis. Recent studies have shown that the NLRP3 inflammasome participates in the initiation and progression of diabetic atherosclerosis through pathological mechanisms such as ß-cell dysfunction, insulin resistance, endothelial cell dysfunction, monocyte adhesion and infiltration, and smooth muscle cell proliferation and migration. In diabetic atherosclerosis, Chinese medicine has been proven effective for the inflammatory response mediated by the NLRP3 inflammasome. This review summarizes the latest progress on the NLRP3 inflammasome in the pathogenesis and potential Chinese medicine treatment of diabetic atherosclerosis.


Assuntos
Aterosclerose , Diabetes Mellitus , Aterosclerose/tratamento farmacológico , China , Diabetes Mellitus/tratamento farmacológico , Humanos , Inflamassomos/metabolismo , Interleucina-1beta/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo
3.
Mol Cell Biochem ; 476(7): 2777-2789, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33721156

RESUMO

Hyperglycemia-induced endothelial dysfunction plays a major role in the pathogenesis of diabetic vascular complications. MicroRNAs are potential therapeutic agents to improve hyperglycemia-induced endothelial dysfunction. This study examined the relationship of miR-9 with Notch1 signaling in hyperglycemia-induced endothelial dysfunction. Human umbilical vein endothelial cells (HUVECs) were exposed to 30 mM glucose concentration. Cell viability including proliferation, adhesion, migration and tube formation was significantly impaired. Quantitative real time polymerase chain reaction (qRT-PCR) or Western blot demonstrated that miR-9 expression remarkably decreased and expression of Notch1 and its effectors (Hes1, Hey1, Hey2) were upregulated. Transfection with miR-9 improved cell function, inhibited mRNA and protein expression of Notch1 and its effectors. Although basal expression of the arterial endothelium biomarker Ephrin B2 was almost undetectable in HUVECs, double-label immunofluorescence revealed that transfection with miR-9 upregulated Ephrin B2 expression. By contrast, such protective effects of miR-9 overexpression were eliminated due to use of miR-9 inhibitor. Dual luciferase assay further confirmed a significant inverse correlation between miR-9 and Notch1. In addition, Notch1 overactiviation was mimicked in HUVECs by transfecting with Notch1 intracellular domain (NICD1). MiR-9 significantly inhibited NICD1 mRNA expression and alleviated hyperglycemia-induced injury of the NICD1-overexpressing cells. Taken together, our data support upregulating miR-9 expression as a potential therapeutic strategy to antagonize hyperglycemia-induced injury by inhibiting Notch1 signaling.


Assuntos
Regulação da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana/metabolismo , Hiperglicemia/metabolismo , MicroRNAs/biossíntese , Neovascularização Fisiológica , Receptor Notch1/metabolismo , Transdução de Sinais , Células Endoteliais da Veia Umbilical Humana/patologia , Humanos , Hiperglicemia/genética , Hiperglicemia/patologia , MicroRNAs/genética , Receptor Notch1/genética
4.
Diabetes Metab Syndr Obes ; 14: 4931-4944, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35002266

RESUMO

BACKGROUND: Data are limited on the effect of diabetes mellitus (DM) on the prognosis of acute coronary syndrome (ACS) patients with heart failure with midrange ejection fraction (HFmrEF) who have undergone percutaneous coronary intervention (PCI). This study aimed to investigate the relationship between type 2 DM (T2DM) and 3-year outcomes in such a population. METHODS: A total of 377 ACS patients with HFmrEF (left ventricular EF 40%-49%) who had undergone PCI (132 diabetic and 245 nondiabetic patients) were included in the analysis. The primary outcome was a composite end point of all-cause death or HF rehospitalization. Cox proportional-hazard regression analysis and Kaplan-Meier tests were used to assess the effect of DM on the primary outcome. Sensitivity analysis was conducted with propensity score-matching analysis. RESULTS: During a follow-up of 3 years, diabetic patients had higher incidence of the primary outcome than nondiabetic patients (96.1 vs 44.6 per 1,000 patient-years, incidence ratio 2.301, 95% CI 1.334-3.969; P=0.002). Multivariate analysis showed that DM was associated with a significant increase in the composite outcome of all-cause death or HF rehospitalization (adjusted HR 2.080, 95% CI 1.115-3.878; P=0.021). Sensitivity analysis further confirmed that DM was an independent prognostic factor of long-term adverse outcomes for ACS patients with HFmrEF who had undergone PCI (adjusted HR 3.792, 95% CI 1.802-7.980; P<0.001). CONCLUSION: Among ACS patients with HFmrEF who had undergone PCI, T2DM comorbidity was significantly associated with worse long-term outcomes.

5.
Scanning ; 2020: 8840963, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33381255

RESUMO

Here, we show that when the oxidation treatment temperature exceeded 600°C, the tensile strength of SiC/SiC begins to decrease. Oxidation leads to the damages on the PyC fiber/matrix interface, which is replaced by SiO2 at higher temperature. The fracture mode converts from fiber pull-out to fiber-break as the fiber/matrix interface is filled with SiO2. Oxidation time also plays an important role in affecting the tensile strength of SiC/SiC. The tensile modulus decreases with temperature from RT to 800°C, then increases above 800°C due to the decomposition of remaining CSi x O y and crystallization of the SiC matrix. A special surface densification treatment performed in this study is confirmed to be an effective approach to reduce the oxidation damages and improve the tensile strength of SiC/SiC after oxidation.

6.
Sci Rep ; 8(1): 14374, 2018 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-30258201

RESUMO

Ceramic substrates play key roles in power electronic device technology through dissipating heat, wherein both high thermal conductivity and mechanical strength are required. The increased power of new devices has led to the replacement of Al2O3 by high thermal conducting AlN and further ß-Si3N4 based substrates. However, the low mechanical strength and/or anisotropic mechanical/thermal properties are still the bottlenecks for the practical applications of these materials in high power electronic devices. Herein, using a combination of density functional theory and modified Debye-Callaway model, two new promising substrate materials γ-Si3N4 and γ-Ge3N4 are predicted. Our results demonstrate for the first time that both compounds exhibit higher room temperature thermal conductivity but less anisotropy in expansion and heat conduction compared to ß-Si3N4. The mechanism underpins the high RT κ is identified as relatively small anharmonicity, high phonon velocity and frequency. The suitability of these two nitrides as substrate materials was also discussed.

7.
RSC Adv ; 8(34): 19171-19180, 2018 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-35539636

RESUMO

A novel Hf-based anti-oxidation coating has been prepared on the surface of low-density carbon-bonded carbon fiber composites (CBCFs). The coating exhibits a gradient transition structure, with mainly HfB2, Hf2Si and SiC ceramics. Oxyacetylene torch testing has been utilized to evaluate the ablation resistance under the condition ranging from 1.6 MW m-2 to 2.2 MW m-2 for 300 s. The experimental results show that the as-prepared Hf-based coating can effectively protect CBCFs under high-temperature oxidation conditions. The surface maximum temperature can reach 1616-2037 °C, and the mass ablation rates vary from -3.5 × 10-5 g s-1 cm-2 to 1.5 × 10-5 g s-1 cm-2. The formation of a dense SiO2 glass layer embedded with HfO2 grains or particle accumulation in the HfO2 layer is responsible for the good ablation resistance.

8.
J Nanosci Nanotechnol ; 15(9): 7402-6, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26716344

RESUMO

ZrB2 and ZrB2-SiC powders are synthesized by a sol-gel method from zirconium n-propoxide, tetraethyl orthosilicate (only for ZrB2-SiC), boric acid, and sucrose. After reduction at 1550 degrees C, both ZrB2 and ZrB2-SiC are unconsolidated, soft gray powders. The ZrB2-SiC particles have an equiaxed shape with a diameter of about 800 nm and a uniform size distribution. The SiC may be very finely distributed, because we barely find SiC among ZrB2 particles when using energy dispersive X-ray spectroscopy (EDS), although both ZrB2 and SiC are identified by X-ray diffractometry (XRD).

9.
Nanoscale ; 6(14): 8002-9, 2014 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-24906180

RESUMO

Both structural and compositional modulations are important for high-performance electrode materials in energy conversion/storage devices. Here hierarchical-structure nitrogen-rich hybrid porous carbon capsules with bamboo-like carbon nanotube whiskers (N-CC@CNTs) grown in situ have been specifically designed, which combine the advantageous features of high surface area, abundant active sites, easy access to medium and favorable mass transport. As a result, the newly prepared N-CC@CNTs show highly efficient catalytic activity in oxygen reduction reaction in alkaline media for fuel cells, which not only outperforms commercial Pt-based catalysts in terms of kinetic limiting current, stability and tolerance to methanol crossover effect, but is also better than most of the nanostructured carbon-based catalysts reported previously. On the other hand, as an anode material for lithium ion batteries, the N-CC@CNTs obtained also exhibit an excellent reversible capacity of ca. 1337 mA h g(-1) at 0.5 A g(-1), outstanding rate capability and long cycling stability, even at a current density of 20 A g(-1). The capacity is the highest among all the heteroatom-doped carbon materials reported so far, and is even higher than that of many of the composites of metal, metal oxides or metal sulfides with carbon materials.

10.
Nanoscale ; 6(12): 6448-51, 2014 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-24807679

RESUMO

A flexible all-in-one single fiber supercapacitor has been fabricated through region-specific reduction of graphene oxide (GO) fiber by laser irradiation, and thus reduced GO layers as electrodes and GO as the separator are integrated into one single fiber. This in-fiber supercapacitor with high mechanical flexibility and high performance could be woven into the textile for wearable electronics and beyond.

11.
ACS Nano ; 6(6): 5457-64, 2012 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-22591354

RESUMO

Preparation of strong, flexible, and multifunctional carbon-based films has attracted considerable interest not only in fundamental research areas but also for industrial applications. We report a binder-free, ultrastrong, and foldable carbon nanotube (CNT) film using aligned few-walled nanotube sheets drawn from spinnable nanotube arrays. The film exhibits tensile strengths up to ∼2 GPa and a Young's modulus up to ∼90 GPa, which is markedly superior to other types of carbon-based films reported, including commercial graphite foils, buckypapers, and graphene-related papers. The film can bear severe bending (even being folded) and shows good structure integrity and negligible change in electric conductivity. The unique structure of the CNT film (good nanotube alignment, high packing density) provides the film with direct and efficient transport paths for electricity. As a flexible charge collector, it favors a magnesium oxide coating to exhibit high charge/discharge rate stability and an excellent electrochemical capacitance close to its theoretical value.


Assuntos
Membranas Artificiais , Nanotubos de Carbono/química , Nanotubos de Carbono/ultraestrutura , Força Compressiva , Módulo de Elasticidade , Condutividade Elétrica , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície , Resistência à Tração
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