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1.
Circ Cardiovasc Imaging ; 16(9): e015340, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37725670

RESUMEN

BACKGROUND: Rapid plaque progression (RPP) is associated with a higher risk of acute coronary syndromes compared with gradual plaque progression. We aimed to develop and validate a coronary computed tomography angiography (CCTA)-based radiomics signature (RS) of plaques for predicting RPP. METHODS: A total of 214 patients who underwent serial CCTA examinations from 2 tertiary hospitals (development group, 137 patients with 164 lesions; validation group, 77 patients with 101 lesions) were retrospectively enrolled. Conventional CCTA-defined morphological parameters (eg, high-risk plaque characteristics and plaque burden) and radiomics features of plaques were analyzed. RPP was defined as an annual progression of plaque burden ≥1.0% on lesion-level at follow-up CCTA. RS was built to predict RPP using XGBoost method. RESULTS: RS significantly outperformed morphological parameters for predicting RPP in both the development group (area under the receiver operating characteristic curve, 0.82 versus 0.74; P=0.04) and validation group (area under the receiver operating characteristic curve, 0.81 versus 0.69; P=0.04). Multivariable analysis identified RS (odds ratio, 2.35 [95% CI, 1.32-4.46]; P=0.005) as an independent predictor of subsequent RPP in the validation group after adjustment of morphological confounders. Unlike unchanged RS in the non-RPP group, RS increased significantly in the RPP group at follow-up in the whole dataset (P<0.001). CONCLUSIONS: The proposed CCTA-based RS had a better discriminative value to identify plaques at risk of rapid progression compared with conventional morphological plaque parameters. These data suggest the promising utility of radiomics for predicting RPP in a low-risk group on CCTA.


Asunto(s)
Angiografía por Tomografía Computarizada , Tomografía Computarizada por Rayos X , Humanos , Estudios Retrospectivos , Angiografía , Corazón
2.
Bioresour Technol ; 376: 128875, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36921637

RESUMEN

Lutein production from microalgae is a sustainable and economical strategy to offer the increasing global demands, but is still challenged with low lutein content at the high-cell density for commercial production. This review summarizes the suitable conditions for cell growth and lutein accumulation, and presents recent cultivation strategies to further improve lutein productivity. Light and nitrogen play critical roles in lutein biosynthesis that lead to the efficient multi-stage cultivation by increasing lutein content at the later stage. In addition, metabolic and genetic designs for carbon regulation and lutein biosynthesis are discussed at the molecule level. The in-situ lutein accumulation in fermenters by regulating carbon metabolism is considered as a cost-effective direction. Then, downstream processes are summarized for the efficient lutein recovery. Finally, challenges of current lutein production from microalgae are discussed. Meanwhile, potential solutions are proposed to improve lutein content and drive down costs of microalgal biomass.


Asunto(s)
Luteína , Microalgas , Microalgas/metabolismo , Biomasa , Carbono/metabolismo , Nitrógeno/metabolismo
3.
ACS Nano ; 16(11): 18038-18047, 2022 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-36322451

RESUMEN

Exploiting highly efficient electrocatalysts toward hydrogen evolution reaction (HER) has a significant role in the mass production of hydrogen energy through water electrolysis. Herein, ginkgo leaf-like Co4N coupled with trace Pt with metallic bond Pt-Co on nickel foam via solvothermal, tannic acid treated, and nitridation procedures for HER (T-Pt-Co4N) is developed. It only requires low overpotentials of 31 mV and 27 mV to achieve 10 mA cm-2 in alkaline and neutral electrolytes, respectively, surpassing the benchmark Pt/C and previously reported values. Moreover, it presents excellent long-term stability in the studied media and also can drive overall water splitting under the assistance of sustainable energies. The specific nanostructure favors the acceleration of the electrocatalytic process by exposing abundant active sites and providing numerous mass transport channels during the catalytic process. Moreover, experimental and theoretical calculation demonstrate that the atomic Pt coordinates with Co to form metallic bond Pt-Co also act as crucial role to boost the electrocatalytic performance by optimizing the reaction kinetics for HER.

4.
J Colloid Interface Sci ; 628(Pt B): 1061-1069, 2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36049282

RESUMEN

Developing efficient and stable catalysts for electrocatalytic hydrogen evolution reaction (HER) with low overpotential is the key point to realizing large-scale hydrogen commercialization. Herein, Ru doped amorphous hollow copper hydroxide nanowires on copper foam (Ru-Cu(OH)x/CF) is prepared by surface chemical oxidization and following solvothermal process. The hollow 3D nanowire structure can provide abundant accessibility active sites, promote electrolyte in filtration and facilitate gas diffusion in the process of the electrochemical reaction. Then, the as-synthesized Ru-Cu(OH)x/CF electrocatalyst exhibits impressive electrocatalytic performance for HER with 45, 80 and 50 mV to drive 10 mA cm-2 in 1.0 M KOH, 1.0 M phosphate-buffered saline (PBS) and 0.5 M H2SO4, respectively, with remarkable long-term stability. Moreover, sustainable energies can power the two-electrode setup with amounts of hydrogen generation. The strategy may be particularly beneficial to explore simple synthesis and high-performance catalysts for HER.


Asunto(s)
Nanocables , Cobre , Hidrógeno , Fosfatos , Concentración de Iones de Hidrógeno
5.
J Agric Food Chem ; 68(15): 4473-4484, 2020 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-32208653

RESUMEN

Long-chain acyl-coenzyme A (CoA) synthetase (LACS) catalyzes the formation of acyl-CoAs from free fatty acids, which is pivotal for lipid metabolism. Here, we confirmed the presence of six CzLACS genes in Chromochloris zofingiensis. Functional complementation and in vitro enzymatic assay indicated that CzLACS2 through CzLACS5 rather than CzLACS1 or CzLACS6 are bona fide LACS enzymes and they have overlapping yet distinct substrate preference. The results of the subcellular colocalization experiment and different expression patterns under three triacylglycerol (TAG)-inducing conditions showed that CzLACS2 through CzLACS4 reside at endoplasmic reticulum (ER) and are involved in TAG biosynthesis, while CzLACS5 resides in peroxisome and participates in fatty acid ß-oxidation. The yeast one-hybrid assay using a library of 50 transcription factors (TFs) constructed in our study identified 12 TFs potentially involved in regulating the expression of CzLACSs. Moreover, heterologous expression of CzLACSs demonstrated their engineering potential for modulating TAG synthesis in yeast and algal cells.


Asunto(s)
Chlorophyceae/enzimología , Coenzima A Ligasas/metabolismo , Familia de Multigenes , Secuencia de Aminoácidos , Chlorophyceae/química , Chlorophyceae/clasificación , Chlorophyceae/genética , Coenzima A Ligasas/genética , Retículo Endoplásmico/enzimología , Retículo Endoplásmico/metabolismo , Filogenia , Transporte de Proteínas , Alineación de Secuencia , Especificidad por Sustrato , Triglicéridos/metabolismo
6.
RSC Adv ; 10(2): 812-817, 2020 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-35494426

RESUMEN

Two novel inorganic-organic hybrid zinc phosphites, namely, [Zn(1,2-bimb)0.5(HPO3)] n (1) and [Zn(1,4-bmimb)0.5(HPO3)] n (2), (1,2-bimb = 1,2-bis(imidazol-1ylmethyl)benzene; 1,4-bmimb = 1,4-bis((2-methyl-1H-imidazol-1yl)methyl)benzene) were synthesized for the first time by hydrothermal reaction. Compound 1 generates a three-dimensional (3D) pillared-layer structure with a 2-nodal 3,4-connected 3,4T15 topology. While compound 2 exhibits a 2D hybrid zinc phosphite sheet with a 3,4-connected 3,4L83 topology network. Utilizing compound 1 and compound 2 as templates and Na2S as an etching agent, a series of highly efficient ZnO/ZnS photocatalysts were obtained. The optimized 1-160 sample demonstrates the highest evolution rate of 22.6 mmol g-1 h-1, exceeding the rate of commercial ZnS samples by more than 14.5 times. The remarkable photocatalytic activity should be attributed to the unique heterojunction structure which shortens the free path of charge carriers and enhances the charge separation efficiency. This work provides a facile strategy for preparing photocatalysts with efficient photocatalytic hydrogen production derived from inorganic-organic hybrid material.

7.
Bioresour Technol ; 282: 94-102, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30852337

RESUMEN

This study explored the co-production of fucoxanthin and stearidonic acid from Isochrysis zhangjiangensis by investigating its carbon metabolism under different light intensities. Results showed high light inhibited the synthesis of fucoxanthin and stearidonic acid, while promoted cell growth and enhanced cellular lipid content compared with low light, achieving 2.4 g/L and 28.55%, respectively. Low light accelerated the accumulation of fucoxanthin and stearidonic acid, which obtained 23.29 mg/g and 17.16% (of total fatty acid). In combination with the molecular analysis, low light redirected carbon skeletons into glyceraldehyde-3-phosphate and diverted into carotenoid especially fucoxanthin. While, high light redistributed the skeletons to Malonyl CoA, citrate and α-Ketoglutarate and then oriented into lipid metabolism. The highest fucoxanthin and stearidonic acid productivity was 2.94 mg L-1 d-1 and 4.33 mg L-1 d-1, respectively, which revealed I. zhanjiangensis is a potential strain for the co-production of fucoxanthin and stearidonic acid.


Asunto(s)
Carbono/metabolismo , Ácidos Grasos Omega-3/metabolismo , Haptophyta/metabolismo , Xantófilas/metabolismo , Carotenoides/metabolismo , Luz , Metabolismo de los Lípidos , Lípidos/biosíntesis
8.
Soft Matter ; 13(10): 2067-2074, 2017 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-28217785

RESUMEN

Generally, surfactants (or amphiphiles) are believed to be necessary components of microemulsions. However, it has been demonstrated that, in the absence of traditional surfactants, microemulsions can also form from a ternary system of two immiscible fluids (i.e., oil and water phases) and an amphi-solvent, but the current understanding of such surfactant-free microemulsions (SFMEs) is very limited. Herein, we report an SFME consisting of the hydrophobic ionic liquid (IL) 1-butyl-3-methylimidazolium hexafluorophosphate (bmimPF6), the protic IL propylamine nitrate (PAN), and water, in which bmimPF6 and PAN are used as the oil phase and the amphi-solvent, respectively. The microstructures and structural transitions of the SFME were investigated using cyclic voltammetry, fluorescence spectroscopy, and ultraviolet-visible spectroscopy. The SFME exhibited water-in-bmimPF6 (W/IL), bicontinuous (BC), and bmimPF6-in-water (IL/W) microstructures, depending on the composition of the ternary system, similar to the case of traditional surfactant-based microemulsions (SBMEs). The three kinds of microstructures were confirmed by cryogenic transmission electron microscopy (cryo-TEM) observations. To the best of our knowledge, this is the first report on SFMEs composed of two ILs as components, especially where one is used as the amphi-solvent.

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