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1.
Adv Mater ; : e2313853, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38684169

RESUMEN

Organic acid-based deep eutectic solvents (DESs) as catalysts always suffer from weak stability and low recyclability due to the accumulation of organic oxidative products in the DES phase. Herein, a completely inorganic deep eutectic solvent (IDES) ZnCl2/PA with zinc chloride (ZnCl2) and phosphoric acid (PA) as precursors is constructed to realize liquid-liquid interface catalysis for desulfurization of fuel and product self-separation for the first time. Owing to the inorganic nature, the organic oxidative products are accumulated at the interface between the IDES and fuel rather than the IDES phase. With this unique feature, the IDES can be reused for at least 15 times without any further treatment in oxidative desulfurization process, showing a state-of-the-art cycle-regeneration stability. Moreover, compared with the reported organic DESs, the IDES also reveals more attractive catalytic oxidative desulfurization performance. Experimental and theoretical studies indicate that the strong coordination Zn···O═P and the strong adsorption energy between IDES and sulfides enhance the activation of H2O2 to reactive oxygen species, leading to the superior catalytic performance in oxidative desulfurization of fuel.

2.
Front Endocrinol (Lausanne) ; 15: 1372413, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38529390

RESUMEN

Introduction: Ovarian cancer (OV) is a highly lethal gynecological malignancy with a poor prognosis. Lactate metabolism is crucial for tumor cell survival, proliferation, and immune evasion. Our study aims to investigate the role of lactate metabolism-related genes (LMRGs) in OV and their potential as biomarkers for prognosis, immune microenvironment, and immunotherapy response. Methods: Ovarian samples were collected from the TCGA cohort. And 12 lactate-related pathways were identified from the MsigDB database. Differentially expressed genes within these pathways were designated as LMRGs, which undergo unsupervised clustering to identify distinct clusters based on LMRGs. Subsequently, we assessed survival outcomes, immune cell infiltration levels, Hallmaker pathway activation patterns, and chemotaxis among different subtypes. After conducting additional unsupervised clustering based on differentially expressed genes (DEGs), significant differences in the expression of LMRGs between the two clusters were observed. The differentially expressed genes were subjected to subsequent functional enrichment analysis. Furthermore, we construct a model incorporating LMRGs. Subsequently, the lactate score for each tumor sample was calculated based on this model, facilitating the classification of samples into high and low groups according to their respective lactate scores. Distinct groups examined disparities in survival prognosis, copy number variation (CNV), single nucleotide variation (SNV), and immune infiltration. The lactate score served as a quantitative measure of OV's lactate metabolism pattern and an independent prognostic factor. Results: This study investigated the potential role of LMRGs in tumor microenvironment diversity and prognosis in OV, suggesting that LMRGs play a crucial role in OV progression and the tumor microenvironment, thus serving as novel indicators for prognosis, immune microenvironment status, and response to immunotherapy.


Asunto(s)
Variaciones en el Número de Copia de ADN , Neoplasias Ováricas , Humanos , Femenino , Neoplasias Ováricas/genética , Pronóstico , Ácido Láctico , Microambiente Tumoral/genética
3.
Adv Sci (Weinh) ; 11(18): e2401996, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38482957

RESUMEN

Porous Ionic Liquids (PILs) have gained attention but facing challenges in catalysis, especially in liquid-liquid two-phase reactions due to limited catalytic sites and hydrophilicity control. This work engineered a Type III PILs (PILS-M) using zeolitic imidazolate framework-8 (ZIF-8) confined phosphomolybdic acid (HPMo) as the microporous framework and N-butyl pyridine bis(trifluoromethane sulfonyl) imide ionic liquid ([Bpy][NTf2]) as the solvent. The PILS-M not only combines the advantages of traditional ionic liquids and microporous frameworks, including excellent extraction, high dispersion of catalytically active species, remarkable stability, etc., but also can make the inner surface of ZIF-8 turned to be hydrophilic that favors the contact between aqueous hydrogen peroxide oxidant and catalytically active sites for the promotion of catalytic performance in reactive extractive desulfurization (REDS) processes of fuel oils. This study demonstrates Type III PILs' potential as catalysts for sustainable chemical processes, offering insights into versatile PILs applications in diverse fields.

4.
Bioconjug Chem ; 35(3): 400-411, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38366969

RESUMEN

Photodynamic therapy (PDT) is a cancer treatment strategy that utilizes photosensitizers to convert oxygen within tumors into reactive singlet oxygen (1O2) to lyse tumor cells. Nevertheless, pre-existing tumor hypoxia and oxygen consumption during PDT can lead to an insufficient oxygen supply, potentially reducing the photodynamic efficacy. In response to this issue, we have devised a pH-responsive amphiphilic triblock fluorinated polymer (PDP) using copper-mediated RDRP. This polymer, composed of poly(ethylene glycol) methyl ether acrylate, 2-(diethylamino)ethyl methacrylate, and (perfluorooctyl)ethyl acrylate, self-assembles in an aqueous environment. Oxygen, chlorine e6 (Ce6), and doxorubicin (DOX) can be codelivered efficiently by PDP. The incorporation of perfluorocarbon into the formulation enhances the oxygen-carrying capacity of PDP, consequently extending the lifetime of 1O2. This increased lifetime, in turn, amplifies the PDT effect and escalates the cellular cytotoxicity. Compared with PDT alone, PDP@Ce6-DOX-O2 NPs demonstrated significant inhibition of tumor growth. This study proposes a novel strategy for enhancing the efficacy of PDT.


Asunto(s)
Nanopartículas , Fotoquimioterapia , Porfirinas , Humanos , Polímeros de Fluorocarbono , Oxígeno , Línea Celular Tumoral , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Hipoxia/tratamiento farmacológico , Concentración de Iones de Hidrógeno
5.
Phys Chem Chem Phys ; 26(3): 2509-2518, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38170798

RESUMEN

Single-atom catalysts (SACs) have attracted great attention for various chemical reactions because of their strong activity, high metal utilization ratio, and low cost. Here, by using the density functional theory (DFT) method, the stability of a single VIII-group metal atom (M = Ni, Pd, Pt) anchored on the defective hexagonal boron nitride (h-BN) sheet and its possible application in oxidative desulfurization (ODS) are investigated. Calculations show that the stability of the single M atom embedded in the h-BN surface with B and N vacancies is strikingly enhanced compared to that on the perfect h-BN surface. The catalytic activities of the defective h-BN-supported single metal atom are further studied by the activation of molecular oxygen and subsequent oxidation of dibenzothiophene (DBT). O2 is activated to the super-oxo state with large interaction energies on three M/VN surfaces. However, among the three M/VB surfaces, only Pt/VB performs efficient activation of O2. The oxidation of DBT proceeds in two steps; the rate-determining step is the initial step, in which activated O2 oxidizes DBT to produce sulfoxide. By comparing the energy barrier in the first reaction step, both Ni/VN and Pt/VB are revealed as promising candidates for the ODS reaction.

6.
Molecules ; 28(23)2023 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-38067473

RESUMEN

Acidic deep eutectic solvents (DESs) have been considered desirable extractants and catalysts for desulfurization. However, their hydrogen bond donors (HBDs) are usually sole organic acids, which are not conducive to efficient green catalysis. Herein, a novel inorganic-organic dual-acid DES (DADES) was reported for efficient extractive and oxidative desulfurization. Benefiting from the physical interaction among the three components in a DADES, a transparent homogeneous liquid can be obtained even though inorganic acid (boric acid, BA) and organic acid (acetic acid, AA) can be immiscible. Furthermore, the dual-acid HBD can increase the acidity of the DADES and reduce its viscosity, accelerating its mass transfer efficiency and enhancing its catalytic activity. With 1-butyl-3-methylimidazolium chloride ([Bmim]Cl) as the hydrogen bond acceptor, [Bmim]Cl/BA/0.3AA effectively activated hydrogen peroxide and achieved sulfur removal of 96.6% at 40 °C. Furthermore, the universality of the synergistic effect in various DADESs was confirmed by the modulation of the types of organic acids. This study not only motivates the construction of more intriguing novel DESs based on the DADES concept but also highlights their potential in clean fuel production.

7.
Molecules ; 28(23)2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-38067550

RESUMEN

The double-layer PVDF-PVC (D-PP/PP) super-hydrophobic composite membrane was prepared by the coating immersion phase separation method to enhance the mechanical properties of the composite membrane. The D-PP/PP super-hydrophobic membrane was prepared using the casting solution concentration of 12 wt% PVDF-PVC composite membrane as basement and 4% casting of PVDF-PVC coating. The contact angle of the D-PP/PP membrane was 150.4 ± 0.3°, and the scanning electron microscope showed that the surface of the D-PP/PP membrane was covered by a cross-linked micro-nano microsphere. The mechanical properties showed that the maximum tensile force of the D-PP/PP composite membrane was 2.34 N, which was 19.4% higher than that of PVDF-PVC (1.96 N). Nano-graphite was added to the coating layer in the experiment. The prepared double-layer PVDF-PVC-nano-graphite/PVDF-PVC (D-PPG/PP) composite membrane reached 153.7 ± 0.5°, the contact angle increasing by 3.3°. The SEM comparison showed that the D-PPG/PP composite membrane had a more obvious micro-nano level microsphere layer. The mechanical properties are also superior. By preparing the D-PP/PP membrane, the mechanical properties of the membrane were improved, and the super-hydrophobic property of the coating was also obtained. At the same time, it was found that adding nano-graphite to the coating layer can better improve the hydrophobic, mechanical, and self-cleaning properties of the D-PP/PP composite membrane.

8.
Inorg Chem ; 62(43): 17883-17893, 2023 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-37842934

RESUMEN

The exploitation of highly efficient and cost-effective selective adsorbents for adsorptive desulfurization (ADS) remains a challenge. Fortunately, single-atom adsorbents (SAAs) characterized by maximized atom utilization and atomically dispersed adsorption sites have great potential to solve this problem as an emerging class of adsorption materials. Herein, aiming at improving the efficiency of ADS performance via the economical and feasible strategy, the desirable SAAs have been fabricated by uniformly anchoring aluminum (Al) atoms on hexagonal boron nitride nanofibers (BNNF) via an in situ pyrolysis method. Remarkably, Al-BN-1.0 exhibited a superior adsorption capacity of 46.1 mg S/g adsorbent for dibenzothiophene, with a 45% increase in adsorption capacity compared to the pristine BNNF. Additionally, it demonstrated excellent adsorption of other thiophene sulfides. Moreover, the ADS mechanisms have been investigated through special adsorption experiments combined with density functional theory (DFT) calculations. It was demonstrated that the superior ADS performance and selectivity of Al-BN-1.0 originate from the sulfur-aluminum (S-Al) and π-π interactions cooperating synergistically. This work would cast light on a novel fabrication strategy for the SAAs based on the two-dimensional material with a tunable metal site configurations and densities for varied selective adsorption and separation.

9.
J Colloid Interface Sci ; 652(Pt B): 1836-1847, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37683411

RESUMEN

Porous ionic liquids (PILs) offer a distinctive combination of liquid-like fluidity and solid porosity, making them well-suited for various applications including separation, catalysis, and energy storage. Nevertheless, the design limitations and complex synthesis processes have hindered the development of PILs. Here, the one-step coupling neutralization reaction (OCNR) method has been first proposed for the controllable synthesis of functionalized protic porous ionic liquids (PPILs). Specifically, three types of PPILs have been synthesized based on tuning the position of the corona amino functional groups. The results indicate the crucial role of protic ion pairs in the formation of pure liquid PPILs with low viscosity. The extraction efficiency has obviously increased after introducing the porous materials from 38.5% to 51.9%. The results showed PPILs play good extraction-adsorption coupled desulfurization (EADS) performance. The density functional theory (DFT) results show that both the protic ion pairs and the porous structure have significant roles in EADS, with the former offering CH···π interactions, while the latter provides hydrogen bonding (CH···O) interactions. Ultimately, the strategy simplifies the synthesis process, providing a new idea for the directional design of low-viscosity PILs with specific functions.

10.
Molecules ; 28(18)2023 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-37764473

RESUMEN

Tumor hypoxia, which is mainly caused by the inefficient microvascular systems induced by rapid tumor growth, is a common characteristic of most solid tumors and has been found to hinder treatment outcomes for many types of cancer therapeutics. In this study, an amphiphilic block copolymer, poly (ethylene glycol) methyl ether acrylate-block-n-butyl acrylate (PEGA-BA), was prepared via the ATRP method and self-assembled into core-shell micelles as nano radiosensitizers. These micelles encapsulated a photosensitizer, Chlorin e6 (Ce6), and demonstrated well-defined morphology, a uniform size distribution, and high oxygen loading capacity. Cell experiments showed that PEGA-BA@Ce6@PFCE micelles could effectively enter cells. Further in vitro anticancer studies demonstrated that the PEGA-BA@Ce6@PFCE micelles significantly suppressed the tumor cell survival rate when exposed to a laser.

11.
Molecules ; 28(11)2023 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-37298895

RESUMEN

This paper presents a highly efficient porous adsorbent PGMA-N prepared through a series of amination reactions between polyglycidyl methacrylate (PGMA) and different polyamines. The obtained polymeric porous materials were characterized using Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), specific surface area test (BET), and elemental analysis (EA). Thereinto, the PGMA-EDA porous adsorbent exhibited excellent ability to synergistically remove Cu(II) ions and sulfamethoxazole from aqueous solutions. Moreover, we studied the effects of pH, contact time, temperature, and initial concentration of pollutants on the adsorption performance of the adsorbent. The experimental results showed that the adsorption process of Cu(II) followed the pseudo-second-order kinetic model and Langmuir isotherm. The maximum adsorption capacity of PGMA-EDA for Cu(II) ions was 0.794 mmol/g. These results indicate that PGMA-EDA porous adsorbent has great potential for application in treating wastewater coexisting with heavy metals and antibiotics.


Asunto(s)
Cobre , Contaminantes Químicos del Agua , Cobre/química , Agua/química , Espectroscopía Infrarroja por Transformada de Fourier , Sulfametoxazol , Porosidad , Adsorción , Contaminantes Químicos del Agua/química , Cinética , Concentración de Iones de Hidrógeno
12.
Inorg Chem ; 62(23): 9199-9208, 2023 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-37229753

RESUMEN

Developing catalysts with optimized surface properties is significant for advanced catalysis. Herein, a rational architectural design is proposed to successfully synthesize yolk-shell nickel molybdate with abundant oxygen vacancies (YS-VO-NMO) via an acid-assisted defect engineering strategy. Notably, YS-VO-NMO with the yolk-shell structure shows complex nanoconfined interior space, which is beneficial to the mass transfer and active sites exposure. Moreover, the defect engineering strategy is of great importance to modulate the surface electronic structure and atomic composition, which contributes to the enrichment of oxygen vacancies. Benefiting from these features, the higher hydrogen peroxide activation is achieved by YS-VO-NMO to produce more hydroxyl radicals compared with untreated nickel molybdate. Consequently, the defect-engineered YS-VO-NMO not only features superior catalytic activity (99.5%) but also retains high desulfurization efficiency after recycling eight times. This manuscript provides new inspiration for designing more promising defective materials via defect engineering and architecture for different applications besides oxidative desulfurization.

13.
ACS Omega ; 8(6): 5593-5606, 2023 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-36816690

RESUMEN

Oxidative desulfurization (ODS) has been proved to be an efficient strategy for the removal of aromatic sulfur compounds from diesel oils, which are one of the main sources of air pollution. Heteropolyacid catalysts are highly active species for ODS, but the promotion of their catalytic activity and clarification of their catalytic mechanism remain an important issue. Herein, a series of novel imidazole-based heteropolyacid catalysts are prepared by a one-pot method for multiphase deep ODS of fuel with hydrogen peroxide as an oxidant. The experimental results show that the desulfurization performance of the prepared imidazole-based heteropolyacid catalysts is high up to 99.9% under mild conditions. The catalyst also possesses excellent recovery performance, and the desulfurization activity remains at 97.7% after being recycled seven times. Furthermore, density functional theory calculation is first employed to clarify the origin of the high desulfurization activity, and the results show that with the imidazole-based heteropolyacid (HPW-VIM) as the catalyst, the energy barrier is much lower than that with phosphotungstic acid (HPW) as the catalyst.

14.
J Colloid Interface Sci ; 634: 1005-1013, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36571854

RESUMEN

The direct conversion of CO2 into reusable CH4 fuel by solar energy can effectively solve the problems of energy crisis and carbon emissions. However, the challenge of photocatalytic CO2 reduction to produce CH4 is still low conversion efficiency and poor selectivity. Here, surface brominated carbon nitride (named CNBr) is fabricated for stable and efficient photocatalytic CO2 reduction to produce CH4 with a rate of 16.68 µmol h-1 g-1 (70.27 % selectivity). Br atom in CNBr can substitute the N atom in the tri-s-triazine unites, which promotes local charge separation, narrows band gap and deepens the conduction band of CNBr. Benefiting from Br as active sites, CO2 can be enriched on the catalyst surface, and localized photogenerated electrons can activate the adsorbed CO2 to form CH4 through subsequent hydrogenation. Density functional theory results suggest that Br doping can effectively reduce the energy barrier of the rate-limiting step, accelerate the reaction, and induce the formation of *CHO, thereby improving the selectivity of CH4. This work reveals that surface modification can simultaneously increase the activation site of CO2 adsorption activation, enhance light absorption and accelerate charge, laying a solid foundation for the future design of carbon nitride based photocatalyst with high performance.

15.
Inorg Chem ; 61(51): 21067-21075, 2022 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-36511781

RESUMEN

Modulating the electronic characteristics of catalysts plays a significant role in optimizing their catalytic activity. Herein, Mn-doped nickel molybdate (MNMO) nanorods are synthesized via replacing the partial Ni sites by the Mn element, engineering a bimetallic synergistic effect to enhance the activation of oxygen (O2). Compared with the extremely low catalytic activity of pristine nickel molybdate (NiMoO4), complete desulfurization can be achieved by MNMO under the same reaction conditions. Characterization results show that the electronic structure and surface atomic composition of pure NiMoO4 will be modulated owing to the introduction of Mn atoms, leading to the enhancement of the oxygen vacancy content and stronger O2 activation capacity. Besides, the optimized catalyst MNMO-20 also displays satisfactory cycle performance, and the sulfur removal of dibenzothiophene still maintains 96.1% after six times of recycling. The distinctive engineering strategy and simple synthesis method provide a new insight in designing and developing oxidative desulfurization catalysts with high stability and effectivity.

16.
Can J Gastroenterol Hepatol ; 2022: 9094934, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35991365

RESUMEN

Delta-shaped gastroduodenostomy (DSGD) and overlap gastroduodenostomy (OGD) are the two most widely used intracorporeal Billroth I anastomosis methods after distal gastrectomy. In this study, we compared the short-term outcomes of DSGD and OGD in total laparoscopic distal gastrectomy (TLDG). In a retrospective cohort study, we examined 92 gastric cancer patients who underwent TLDG performed by the same surgeon between January 2014 and June 2018. All patients underwent Billroth I reconstruction (OGD, n = 45; DSGD, n = 47) and D2 lymph node dissection. We retrospectively reviewed the surgical outcomes, clinical pathological results, and endoscopy results. Laparoscopic surgery was successfully performed in both groups without conversion to open surgery. The demographic and clinical characteristics were similar between the two groups (P > 0.05). There were no significant differences between the two groups in operation time (158.9 ± 13.6 min vs. 158.8 ± 14.8 min, P=0.955), anastomotic time (19.4 ± 3.0 min vs. 18.8 ± 2.9 min, P=0.354), intraoperative blood loss (88.9 ± 25.4 mL vs. 83.7 ± 24.3 mL, P=0.321), number of lymph node dissections (31.0 ± 7.1 vs. 29.2 ± 7.5, P=0.229), length of hospital stay (8.8 ± 2.7 days vs. 9.1 ± 3.0 days, P=0.636), fluid intake time (3.1 ± 0.7 days vs. 3.2 ± 0.7 days, P=0.914), and morbidity of postoperative complications (6.7% [3/45] vs. 10.6% [5/47], P=0.499). Endoscopy performed 6 months postoperatively showed that the residual food (P=0.033), gastritis (P=0.029), and bile (P=0.022) classification score significantly decreased in the OGD group, and there were no significant differences 12 months postoperatively. OGD is a safe and effective reconstruction technique with comparable postoperative surgical outcomes and endoscopy results when compared with those of DSGD.


Asunto(s)
Laparoscopía , Neoplasias Gástricas , Anastomosis Quirúrgica/métodos , Gastrectomía/métodos , Gastroenterostomía/métodos , Humanos , Laparoscopía/métodos , Estudios Retrospectivos , Neoplasias Gástricas/patología , Neoplasias Gástricas/cirugía , Resultado del Tratamiento
17.
Int J Biol Macromol ; 172: 114-123, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33444658

RESUMEN

The aim of this work was to study an improved solvent evaporation method to prepare poly (lactic acid) (PLA) microspheres via foam-transfer. Since the foaming process and its transfer were critical to the improved method, they have been studied. Additionally, the delivery capability of foams was studied as a function of the oil/water ratio, the stirring rate, the concentration of polyvinyl alcohol (PVA) and ethanol (EtOH) in the aqueous phase (ωPVA, ωEtOH). It was found that foaming varied during the preparation process and it influenced the properties of PLA microspheres. When the oil/water ratio (w/w) ≥ 3:10, stirring rate ≥ 600 r/min, ωPVA ≥ 1 wt%, and ωEtOH = 0 wt%, solvent evaporation was able to produce enough foams for foam-transfer, which helped to deliver more than 89 wt% PLA microspheres to the receiving vessel. However, ωPVA ≤ 0.3 wt% and ωEtOH = 20 wt% were unfavorable for maintaining the spherical shape of PLA microspheres and caused the aggregation. The methodology was further used to prepare azoxystrobin-loaded PLA microspheres successfully with a high encapsulation efficiency of 86.54%. This work is meaningful since it enables an efficient and continuous route to prepare functional biodegradable polymer microspheres.


Asunto(s)
Poliésteres/química , Solventes/química , Etanol/química , Microesferas , Polímeros/química , Alcohol Polivinílico/química , Pirimidinas/química , Estrobilurinas/química , Agua/química
18.
RSC Adv ; 11(15): 8782-8792, 2021 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-35423387

RESUMEN

To achieve the poly(propylene carbonate trimellitic anhydride) (PPCTMA) with excellent performance, high molecular weight, enhanced yield and good thermal stability, the ternary composite catalyst system of zinc glutarate/rare earth ternary complex/double metal cyanide (ZnGA/RET/DMC) was proposed to perform the terpolymerization of CO2, propylene oxide and trimellitic anhydride. Since the crystallinity and surface activity point of Zn-Co DMC could significantly influence the catalytic ability, mechanical ball milling was applied to increase the surface area of the Zn-Co DMC catalyst with better surface activity point. Moreover, the ZnGA/RET/DMC composite catalytic system and polycarbonate products were comparatively evaluated by XRD, SEM, FT-IR, TGA, NMR, XPS and TEM. Experimental results showed that the ZnGA/RET/DMC composite catalyst system displayed outstanding synergistic effect on the terpolymerization of CO2, PO and TMA with better selectivity, activity, and higher molecular weight (M w) tercopolymer than those of the individual catalyst. According to optimum reaction conditions, the M w of PPCTMA could be up to 8.29 × 104 g mol-1, and the yield could be up to 66 gpolym/gcat. The alternating tercopolymer, PPCTMA, showed wonderful thermal stability and high decomposition temperature (TGA10% = 313 °C). A possible synergistic catalytic mechanism of the ZnGA/RET/DMC ternary composite catalyst system was also conjectured.

19.
RSC Adv ; 9(62): 35939-35947, 2019 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-35540564

RESUMEN

Hydroxyapatite (HAP) is a widely used biomaterial for bone tissue substitution due to its chemical similarity with the natural bone. Defect-related luminescent HAP materials have the same chemical composition as normal HAP and excellent biocompatibility. However, only few works have focused on the defect-related luminescent HAP materials on bone regeneration. In this work, we systematically investigated the bone regeneration pathway induced by nanostructured particles using defect-related luminescent hydroxyapatite (S2) materials. We monitored the subcellular distribution and location of S2 during osteoblast differentiation with the property of defect-related luminescence. Nano-scale S2 could be internalized by osteoblasts (OBs) via caveolae-mediated endocytosis and macropinocytosis. S2 incorporated into the lysosomes dissolved and released calcium ions for the formation of mineralized nodules. Extracellular S2 also promoted bone regeneration as a nucleation site. Taken together, the physical properties of hydroxyapatite control the bone regeneration pathway in osteoblasts.

20.
Polymers (Basel) ; 10(7)2018 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-30960713

RESUMEN

Polymeric microspheres with different internal structures have been widely used because of their characteristics in the structures. This paper reports a method of controlling the internal structures of polymeric microspheres via the introduction of a water-soluble organic solvent to the continuous phase in the foam phase preparation of porous polymeric microspheres. The introduction of a water-soluble organic solvent enables the control of polymeric microspheres' internal structures, from porous to hollow. Because a water-soluble organic solvent is introduced, the organic solvent may be diffused toward the interface because of the affinity between the organic solvent and the oil droplets, resulting an accumulation of organic solvent molecules at the interface to form an organic solvent layer. The presence of this layer may decrease the evaporation rate of the internal organic solvent in an oil droplet, which extends the time for the mingling of porogen droplets to form a few large pores or even an extremely large single pore inside. This method is also capable of altering the thickness of hollow microspheres' shells in a desired way, with improved efficiency, yield and the capacity for continuous use on an industrial scale.

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