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1.
J Colloid Interface Sci ; 672: 664-674, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38865880

RESUMO

Proton exchange membranes (PEMs) applied in fuel cell technology suffer from the trade-off between fast proton conduction and durable operation involving dimensional stability, mechanical strength, and oxidative resistance. To address this issue, a novel branched polybenzimidazole (brPBI) was synthesized, covalently cross-linked with (3-chloropropyl)triethoxysilane (CTS), and doped with a novel proton conductor FeATMP to prepare brPBI-CTS/FeATMP membranes. The branching degree of brPBI was optimized to achieve high molecular weight while the branching structure offered high free volume, abundant end-groups, and self-cross-linking moiety that enhanced proton conduction and dimensional/mechanical/oxidative stability. Covalent cross-linking with CTS enhanced the dimensional, mechanical, and oxidative stability while improving the water-assisted proton conduction owing to the hydrophilic nature of siloxane structure formed. At 180 ℃, the proton conductivity of the brPBI3-CTS/FeATMP composite membrane reached 0.136, 0.073, and 0.041 S cm-1 at 100 % RH, 50 % RH, and 0 % RH, respectively, while its swelling ratio after immersion in water at 90 ℃ for 24 h was 4.69 %. The performance of the membranes demonstrated that construction of hydrophilic structure by covalent cross-linking was a successful strategy to break the trade-off effect for PEMs.

2.
Eur Radiol ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38777904

RESUMO

OBJECTIVES: To investigate the short-term/long-term impact of pulmonary artery intramural hematoma (PA-IMH) in patients with acute Stanford type A aortic dissection (ATAAD) following surgical repair. MATERIALS AND METHODS: Consecutive patients with ATAAD who received surgical repair at Beijing and Yunnan Fuwai Hospital in 2010-2021 were retrospectively reviewed. Patients with hemorrhage extending along the PA were identified as the PA-IMH group. Multivariable logistics regression was used to obtain the odds ratio (OR), and the Kaplan-Meier method was used to estimate the survival rate. RESULTS: Of the 2046 ATAAD patients, 324 (15.8%) patients were identified with PA-IMH, and 1722 (84.2%) were without PA-IMH. PA-IMH had a higher prevalence in patients with older age, female gender, aortic IMH, and type II aortic dissection. PA-IMH patients incurred excess early mortality compared with non-PA-IMH patients (9.3% vs. 5.6%, OR = 1.86, 95%CI 1.19-2.91, p = 0.006). The results were stable in the subgroup analysis, with an increased risk in older (> 70 years) or DeBakey type II ATAAD patients. Notably, an increase in the degree and extent of PA-IMH exacerbated the risk of early mortality. However, after landmark analysis at 30-day postsurgery, no significant difference was noted in the long-term outcomes between PA-IMH and non-PA-IMH groups (p = 0.440). The 5-year survival rates were 87.1% (95%CI: 83.3%, 91.1%) and 90.1% (95%CI: 88.5%, 91.7%), respectively. CONCLUSIONS: The presence of PA-IMH in ATAAD patients is common and is independently associated with increased early mortality after surgical repair, especially in those with older age (> 70) or type II dissection. However, such detrimental effects do not persist in the long-term follow-up among patients who survived hospital discharge. CLINICAL RELEVANCE STATEMENT: We confirmed that PA-IMH significantly increases early postoperative mortality in patients with acute type A aortic dissection, especially in older patients or DeBakey type II dissection. This should prompt further investigation of the incremental role of PA-IMH in this pathology. KEY POINTS: Acute type A aortic dissection mortality gets worse when pulmonary artery intramural hematoma is present. Pulmonary artery-intramural hematoma increased the risk of early mortality but not affect long-term prognosis. Further research should investigate the effects of pulmonary artery intramural thrombus on aortic dissection.

3.
Front Oncol ; 11: 660712, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33912467

RESUMO

Curcumin [(1E,6E) ­1,7­bis(4­hydroxy­3­methoxyphenyl) hepta­1,6­diene­3,5­ dione] is a natural polyphenol derived from the rhizome of the turmeric plant Curcuma longa. Accumulated evidences have presented curcumin's function in terms of anti-inflammatory, antioxidant properties, and especially anti-tumor activities. Studies demonstrated that curcumin could exert anti-tumor activity via multiple biological signaling pathways, such as PI3K/Akt, JAK/STAT, MAPK, Wnt/ß-catenin, p53, NF-ĸB and apoptosis related signaling pathways. Moreover, Curcumin can inhibit tumor proliferation, angiogenesis, epithelial-mesenchymal transition (EMT), invasion and metastasis by regulating tumor related non-coding RNA (ncRNA) expression. In this review, we summarized the roles of curcumin in regulating signaling pathways and ncRNAs in different kinds of cancers. We also discussed the regulatory effect of curcumin through inhibiting carcinogenic miRNA and up regulating tumor suppressive miRNA. Furthermore, we aim to illustrate the cross regulatory relationship between ncRNA and signaling pathways, further to get a better understanding of the anti-tumor mechanism of curcumin, thus lay a theoretical foundation for the clinical application of curcumin in the future.

4.
Ying Yong Sheng Tai Xue Bao ; 23(6): 1577-84, 2012 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-22937646

RESUMO

A pot experiment with soybean cultivar Nannong 99-6 was conducted to study its growth and C and N metabolism at seedling and flowering stages under the stress of different duration of waterlogging. Waterlogging inhibited the soybean growth. The plant biomass, leaf area, leaf pigment content, and photosynthesis rate all decreased significantly, and the leaf malonyldialdehyde (MDA) content had a significant increase. The change ranges of the physiological indices increased with increasing waterlogging duration. After the release of the stress, the plants had some recovery. The recovery capability in treatment waterlogging for 10 d was stronger than that in the treatment waterlogging for 20 d. The leaf soluble C and N and key enzymes had different responses to waterlogging. Soluble sugar content and glutamine synthease and sucrose synthease activities all increased, but soluble protein content decreased. The influence of waterlogging on the plant biomass, leaf area, and MDA content was smaller at seedling stage than at flowering stage. It was suggested that the shorter the waterlogging duration was, the lesser damage the soybean plant suffered, and the stronger the recovery capability was. Soybean plant could recover itself after waterlogging for 10 d.


Assuntos
Carbono/metabolismo , Inundações , Glycine max/metabolismo , Nitrogênio/metabolismo , Estresse Fisiológico , Flores/metabolismo , Chuva , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Glycine max/crescimento & desenvolvimento
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