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1.
Int J Biol Macromol ; 225: 266-276, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36336155

RESUMO

In this work, a biomass composite material (CS@NC@PA-Na) was prepared from chitosan (CS), nano-cellulose (NC) and sodium phytate (PA-Na). The prepared products were characterized by scanning electron microscopy (SEM), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectrometry (XPS) and X-ray diffraction (XRD). The fire/water safety and antimicrobial properties of the CS@NC@PA-Na were fully studied. The results indicated CS@NC@PA-Na (50 mg) could effectively reduce the concentration of methyl orange by 85 % under 30 min adsorption. Meanwhile, only 5 wt% CS@NC@PA-Na could increase the limiting oxygen index (LOI) value of epoxy resin composite from 24.5 to 30.1 %, and decrease the peak heat/smoke release rate by 29.5 and 33.3 %, respectively. Moreover, CS@NC@PA-Na also exhibited excellent antibacterial effect. This work provides an efficient, feasible and eco-friendly route for large-scale production of multi-functional CS-based biomass materials that could be used in the fields of fire safety and environmental conservation.


Assuntos
Quitosana , Purificação da Água , Quitosana/farmacologia , Quitosana/química , Biomassa , Celulose , Antibacterianos/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
2.
Front Cardiovasc Med ; 9: 1017833, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36451921

RESUMO

Background: Percutaneous coronary intervention (PCI) has a well-established role in revascularization for coronary artery disease. We performed network meta-analysis to provide evidence on optimal intervention strategies for de novo lesions in small coronary arteries. Materials and methods: Enrolled studies were randomized clinical trials that compared different intervention strategies [balloon angioplasty (BA), biolimus-coated balloon (BCB), bare-metal stent (BMS), new-generation drug-eluting stent (New-DES), older generation sirolimus-eluting stent (Old-SES), paclitaxel-coated balloon (PCB), and paclitaxel-eluting stent (PES)] for de novo lesions in small coronary arteries. The primary outcome was major adverse cardiac events (MACE). Results: A total of 23 randomized clinical trials comparing seven intervention devices were analyzed. In terms of the primary outcome, New-DES was the intervention device with the best efficacy [surface under the cumulative ranking curve (SUCRA), 89.1%; mean rank, 1.7], and the Old-SES [risk ratio (RR), 1.09; 95% confidence interval (CI), 0.45-2.64] and PCB (RR, 1.40; 95% CI, 0.72-2.74) secondary to New-DES, but there was no statistically significant difference between these three intervention devices. All DES and PCB were superior to BMS and BA for MACE in both primary and sensitivity analysis. For secondary outcomes, there was no association between all-cause mortality and myocardial infarction (MI) with any intervention strategy, and additionally, the findings of target lesion revascularization (TLR) were similar to the primary outcomes. Conclusion: Paclitaxel-coated balloon yielded similar outcomes to New-DES for de novo lesions in small coronary arteries. Therefore, this network meta-analysis may provide potential support for PCB as a feasible, effective, and safe alternative intervention strategy for the revascularization of small coronary arteries. Systematic review registration: [https://www.crd.york.ac.uk/PROSPERO/#recordDetails], identifier [CRD42022338433].

3.
Small ; 18(47): e2203609, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36251790

RESUMO

Although transition metal carbides/carbonitrides (MXenes) exhibit immense potential for electromagnetic wave (EMW) absorption, their absorbing ability is hindered by facile stacking and high permittivity. Layer stacking and geometric structures are expected to significantly affect the conductivity and permittivity of MXenes. However, it is still a formidable task to simultaneously regulate layer stacking and microstructure of MXenes to realize high-performance EMW absorption. Herein, a simple and viable strategy using electrostatic adsorption is developed to integrate 2D Ti3 C2 Tx MXene nanosheets into 3D hollow bowl-like structures with tunable layer stacking thickness. Density functional theory calculations indicate an increase in the density of states of the d orbital from the Ti atom near the Fermi level and the generation of additional electrical dipoles in the MXene nanosheets constituting the bowl walls upon reducing the layer stacking thickness. The hollow MXene bowls exhibit a minimum reflection loss (RLmin ) of -53.8 dB at 1.8 mm. The specific absorbing performance, defined as RLmin (dB)/thickness (mm)/filler loading (wt%), exceeds 598 dB mm-1 , far surpassing that of the most current MXene and bowl-like materials reported in the literature. This work can guide future exploration on designing high-performance MXenes with "lightweight" and "thinness" characteristics for superior EMW absorption.

4.
Front Cardiovasc Med ; 9: 882303, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35911516

RESUMO

Background and Objectives: Use of drug-coated balloon (DCB)-only strategy for revascularization of native large coronary artery lesions is on the rise. The long-term efficacy of this approach for bifurcation and non-bifurcation lesions remains unknown. We aim to assess the long-term clinical outcomes of DCB-only strategy for the treatment of de novo bifurcation and non-bifurcation lesions in large coronary arteries. Methods: This multicenter, prospective, observational study enrolled 119 patients with de novo coronary lesions in vessels ≥2.75 mm. The primary end point was the rate of clinically driven target lesion failure (TLF), a composite of cardiac death, target vessel myocardial infarction, and clinically driven target lesion revascularization (TLR). Patients were followed up for a median of 2 years. Results: Of 119 patients with 138 lesions, 66 patients (75 lesions) had bifurcation and 53 patients (63 lesions) had non-bifurcation lesions. Average reference vessel diameter was 3.1 ± 0.3 mm, and there was no difference in bifurcation and non-bifurcation group (3.0 ± 0.3 vs. 3.1 ± 0.3mm; p = 0.27). At 2-year follow-up, the TLF occurred in five (4.2%), TLR in four (3.4%), and target vessel revascularization (TVR) in five (4.2%) cases. The frequency of TLR and TVR was higher in the non-bifurcation group (p = 0.04 and 0.02, respectively), but there were no differences in TLF between the two groups (p = 0.17). The cumulative incidence of TLF (Kaplan-Meier estimates) was also not different in the two groups (log-rank p = 0.11). Conclusion: DCB-only strategy for de novo lesions in large coronary arteries appears to be safe and effective for both bifurcation and non-bifurcation lesions. Further randomized clinical trials are warranted to confirm the value of DCB-only strategy in de novo bifurcation lesions of large vessels.

5.
Am J Transl Res ; 8(11): 5005-5015, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27904701

RESUMO

The present study explored changes of the SIRT6/NF-κB pathway in myocardial hypoxia/reoxygenation induced injury and the effects on mitochondrial damage and myocardial damage by regulating SIRT6. SIRT6 expression decreased and NF-κB expression increased in H9c2 cells during hypoxic injury. Cell death and mitochondrial defects paralleled mPTP opening, and a decrease in ΔΨm occurred in hypoxic myocytes compared with normoxic control cells in annexin V and propidium iodide staining and TUNEL results. These effects were suppressed in cells overexpressing SIRT6, but reemerged in cells expressing the SIRT6 mutant. We also found that NF-κB p65 increased in both the cytoplasm and nuclei, which could be repressed by SIRT6 overexpression. The expression level of NF-κB was significantly and negatively correlated with the SIRT6 mRNA level. Our data demonstrated that SIRT6/NF-κB changed during hypoxic injury and SIRT6 overexpression averted mitochondrial defects through inhibition of NF-κB in hypoxic H9c2 cells. Activation of SIRT6 may be a potential method for hypoxia/reoxygenation injury therapy.

6.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 1): o208, 2010 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-21522708

RESUMO

The asymmetric unit of the title compound, C(12)H(8)O(4)·2C(5)H(9)NO, contains one half-mol-ecule of naphthalene-2,6-dicarb-oxy-lic acid (NDA) and one mol-ecule of 1-methyl-pyrrolidin-2-one (NMP): the NDA molecules lie on the crystallographic twofold rotation axes. In the crystal, the components are linked by strong O-H⋯O hydrogen bonds and C-H⋯O inter-actions.

7.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 8): o1794, 2009 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-21583500

RESUMO

The asymmetric unit of title compound, C(8)H(6)O(4)·2C(4)H(9)NO, contains one half-mol-ecule (an inversion centre in P21/n generates the other half of the molecule) of terephthalic acid (TA) and one mol-ecule of N,N-dimethyl-acetamide (DMAC). The DMAC mol-ecules are linked to TA by strong O-H⋯O hydrogen bonds.

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