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1.
Anal Bioanal Chem ; 409(5): 1435-1440, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27864595

RESUMEN

Organophosphate esters (OPEs), widely used as flame retardants and plasticizers, are regarded as emerging pollutants. OPEs are prone to concentrate into residual activated sludge, which might cause secondary pollution if not suitably treated. Composting is an economical and effective approach to make sewage sludge stable and harmless. Therefore, it is essential to develop a novel method for analyzing OPEs in sewage sludge compost samples. However, in the composting process, large amounts of amendments are doped into the sludge to adjust the carbon-nitrogen ratio. Amendment has a strong capacity for adsorption and thus induces a decrease of extraction efficiency. This study developed a novel procedure for determining OPEs in compost samples. Accelerated solvent extraction (ASE) and solid phase extraction (SPE) were used for extracting and concentrating the OPEs from sewage sludge compost samples, and then analyzed by UHPLC-MS/MS. Some parameters were optimized in this study, mainly including the extraction solvent type, extraction temperature, static extraction time, extraction cycles, and flush volume. Under the optimal conditions, the proposed method showed good linearity between 0.50 and 100 µg kg-1 with regression coefficients in the range of 0.9984-0.9998. Detection limits were in the range of 0.02-3 µg kg-1 with standard deviations ranging from 2 to 6%. Acceptable recoveries between 56 and 119% for samples spiked at different concentration levels were achieved. In contrast, the recoveries merely ranged from 24 to 58% by using ultrasonic-assisted extraction. Graphical abstract A comparison of recoveries between ultrasonic-assisted extraction (UAS) and accelerated solvent extraction (ASE) for organophosphate esters from sewage sludge compost samples.

2.
J Sep Sci ; 39(22): 4415-4421, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27709787

RESUMEN

Organophosphate esters, widely used as flame retardants and plasticizers, are regarded as a class of emerging pollutants. In this work, a novel approach was developed for the fabrication of a solid-phase microextraction fiber by using hybrid silica-based materials with immobilized ionic liquids with sol-gel technology, and the prepared solid-phase microextraction fiber was then coupled with gas chromatography and flame photometric detection for the analysis of six organophosphate esters. The high loading of 1-hexadecyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide was confined within the hybrid network. The developed solid-phase microextraction fiber possesses a coating thickness of ∼35 µm with good thermal stability and long lifetime. The parameters affecting the extraction efficiency such as extraction time, temperature, pH, and ionic strength of the sample solution were optimized. Under the optimized conditions, the limits of detection were in the range of 0.04-0.95 µg L-1 , and the precision of the method assessed with repeatability and reproducibility of (RSD%) ˂13 and ˂29%, respectively. The proposed method was successfully applied to determine the six organophosphate esters in three real water samples, with recoveries in the range of 64.8-125.4% at two different spiking concentration levels. As a result, the proposed method demonstrated its potential for application in trace determination of organophosphate esters in actual water samples.

3.
ACS Appl Mater Interfaces ; 16(17): 21595-21609, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38635857

RESUMEN

A microneedle transdermal drug delivery system simultaneously avoids systemic toxicity of oral administration and low efficiency of traditional transdermal administration, which is of great significance for acne vulgaris therapy. Herein, eugenol-loaded hyaluronic acid-based dissolving microneedles (E@P-EO-HA MNs) with antibacterial and anti-inflammatory activities are developed for acne vulgaris therapy via eugenol transdermal delivery integrated with photothermal therapy. E@P-EO-HA MNs are pyramid-shaped with a sharp tip and a hollow cavity structure, which possess sufficient mechanical strength to penetrate the stratum corneum of the skin and achieve transdermal delivery, in addition to excellent in vivo biocompatibility. Significantly, E@P-EO-HA MNs show effective photothermal therapy to destroy sebaceous glands and achieve antibacterial activity against deep-seated Propionibacterium acnes (P. acnes) under near-infrared-light irradiation. Moreover, cavity-loaded eugenol is released from rapidly dissolved microneedle bodies to play a sustained antibacterial and anti-inflammatory therapy on the P. acnes infectious wound. E@P-EO-HA MNs based on a synergistic therapeutic strategy combining photothermal therapy and eugenol transdermal administration can significantly alleviate inflammatory response and ultimately facilitate the repair of acne vulgaris. Overall, E@P-EO-HA MNs are expected to be clinically applied as a functional minimally invasive transdermal delivery strategy for superficial skin diseases therapy in skin tissue engineering.


Asunto(s)
Acné Vulgar , Administración Cutánea , Antibacterianos , Eugenol , Ácido Hialurónico , Agujas , Terapia Fototérmica , Propionibacterium acnes , Acné Vulgar/terapia , Acné Vulgar/tratamiento farmacológico , Eugenol/química , Eugenol/farmacología , Ácido Hialurónico/química , Animales , Antibacterianos/química , Antibacterianos/farmacología , Propionibacterium acnes/efectos de los fármacos , Ratones , Sistemas de Liberación de Medicamentos , Humanos , Piel
4.
Chin Med J (Engl) ; 137(2): 209-221, 2024 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-37390491

RESUMEN

BACKGROUND: Bladder cancer, characterized by a high potential of tumor recurrence, has high lifelong monitoring and treatment costs. To date, tumor cells with intrinsic softness have been identified to function as cancer stem cells in several cancer types. Nonetheless, the existence of soft tumor cells in bladder tumors remains elusive. Thus, our study aimed to develop a micro-barrier microfluidic chip to efficiently isolate deformable tumor cells from distinct types of bladder cancer cells. METHODS: The stiffness of bladder cancer cells was determined by atomic force microscopy (AFM). The modified microfluidic chip was utilized to separate soft cells, and the 3D Matrigel culture system was to maintain the softness of tumor cells. Expression patterns of integrin ß8 (ITGB8), protein kinase B (AKT), and mammalian target of rapamycin (mTOR) were determined by Western blotting. Double immunostaining was conducted to examine the interaction between F-actin and tripartite motif containing 59 (TRIM59). The stem-cell-like characteristics of soft cells were explored by colony formation assay and in vivo studies upon xenografted tumor models. RESULTS: Using our newly designed microfluidic approach, we identified a small fraction of soft tumor cells in bladder cancer cells. More importantly, the existence of soft tumor cells was confirmed in clinical human bladder cancer specimens, in which the number of soft tumor cells was associated with tumor relapse. Furthermore, we demonstrated that the biomechanical stimuli arising from 3D Matrigel activated the F-actin/ITGB8/TRIM59/AKT/mTOR/glycolysis pathways to enhance the softness and tumorigenic capacity of tumor cells. Simultaneously, we detected a remarkable up-regulation in ITGB8, TRIM59, and phospho-AKT in clinical bladder recurrent tumors compared with their non-recurrent counterparts. CONCLUSIONS: The ITGB8/TRIM59/AKT/mTOR/glycolysis axis plays a crucial role in modulating tumor softness and stemness. Meanwhile, the soft tumor cells become more sensitive to chemotherapy after stiffening, that offers new insights for hampering tumor progression and recurrence.


Asunto(s)
Cadenas beta de Integrinas , Proteínas Proto-Oncogénicas c-akt , Neoplasias de la Vejiga Urinaria , Animales , Ratones , Humanos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Actinas/metabolismo , Recurrencia Local de Neoplasia , Serina-Treonina Quinasas TOR/metabolismo , Glucólisis , Línea Celular Tumoral , Proliferación Celular , Mamíferos/metabolismo , Proteínas de Motivos Tripartitos/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo
5.
Proc Natl Acad Sci U S A ; 107(5): 1838-43, 2010 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-20080617

RESUMEN

A new class of operator algebras, Kadison-Singer algebras (KS-algebras), is introduced. These highly noncommutative, non-self-adjoint algebras generalize triangular matrix algebras. They are determined by certain minimally generating lattices of projections in the von Neumann algebras corresponding to the commutant of the diagonals of the KS-algebras. A new invariant for the lattices is introduced to classify these algebras.

6.
Proc Natl Acad Sci U S A ; 107(11): 4840-4, 2010 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-20185756

RESUMEN

A new class of operator algebras, Kadison-Singer (KS-) algebras, is introduced. These highly noncommutative, non self-adjoint algebras generalize triangular matrix algebras. They are determined by certain minimally generating lattices of projections in the von Neumann algebras corresponding to the commutant of the diagonals of the KS-algebras. It is shown that these lattices and their reduced forms are often homeomorphic to classical manifolds such as the sphere.

7.
Environ Sci Pollut Res Int ; 30(40): 92007-92026, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37480528

RESUMEN

An intellectual property demonstration city (IPDC) not only promotes innovation, but also brings many unexpected gains, the most prominent of which is carbon reduction. Unfortunately, few scholars have included IPDC and carbon emissions in a unified research framework, ignoring the role of intellectual property protection in environmental governance. Therefore, this paper investigates the impact of IPDC on carbon emissions through a multi-period difference-in-difference (DID) model, a spatial DID model, and a mediating effect model with IPDC policy as a quasi-natural experiment. The research results are as follows: (1) IPDC policy has a significant inhibitory effect on carbon emissions. Compared to non-pilot cities, IPDC policy can reduce carbon emissions by about 20.6%. (2) There are temporal and regional heterogeneity of the IPDC policy on carbon emissions. More specifically, the carbon reduction effect of IPDC is more effective in large cities and cities with richer human capital, stricter environmental regulation, and higher financial development. Meanwhile, the policy effects in 2012 and 2015 are larger than those in 2018, while the policy effects in 2014, 2016, and 2019 are not significant. (3) IPDC policy reduces carbon emissions mainly by stimulating innovation and green innovation, and promoting R&D element agglomeration. (4) IPDC policy has obvious spatial spillover effects and leads to the surrounding cities becoming pollution havens. The above conclusions have implications for designing a better urbanization model to promote innovative development and reduce carbon emissions.


Asunto(s)
Conservación de los Recursos Naturales , Política Ambiental , Humanos , Ciudades , China , Carbono
8.
Adv Healthc Mater ; 12(15): e2203054, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36745877

RESUMEN

Pathogenic bacterial infection is the most frequent wound complication, which has become a major clinical and healthcare challenge in wound management worldwide, leading to impaired healing processes, the risk of amputation, and even death. Here, collagen-based nanocomposite dressings (APZC) with broad-spectrum antibacterial activity are developed to promote the infected full-thickness wound healing. Short rod-like shaped ZnO NPs are synthesized and then coated with polydopamine (PDA) to obtain PDA coated ZnO NPs (PDA@ZnO NPs). Afterward, PDA@ZnO NPs are conjugated on the backbone of a collagen chain, and the obtained collagen-PDA@ZnO NPs conjugate is crosslinked by dialdehyde sodium alginate to fabricate APZC dressings. PDA@ZnO NPs show well dispersibility and are uniformly incorporated into the collagen matrix. APZC dressings have interconnected microporous structure and great physicochemical properties, besides good blood coagulation performance and well cytocompatibility. APZC dressings demonstrate long-lasting and excellently broad-spectrum antimicrobial activity, which can relieve the inflammatory reaction by killing pathogenic bacteria and induce the generation of blood vessels and the orderly deposition of collagen in the wound site, thus promoting infected full-thickness wound healing without obvious scar formation. Overall, the functionalized collagen-based nanocomposite dressings have great potential in the clinical treatment against bacteria-associated wound infection.


Asunto(s)
Nanocompuestos , Infección de Heridas , Óxido de Zinc , Humanos , Óxido de Zinc/química , Cicatrización de Heridas , Colágeno/farmacología , Bacterias , Nanocompuestos/uso terapéutico , Vendajes , Antibacterianos/farmacología , Antibacterianos/química , Infección de Heridas/patología
9.
ACS Appl Mater Interfaces ; 15(19): 22817-22829, 2023 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-37145770

RESUMEN

Antibacterial conductive hydrogels have been extensively utilized in tissue repair and regeneration on account of their unique electrochemical performances and advantages of anti-pathogenic bacterial infection. Here, multi-functional collagen-based hydrogels (CHLY) with adhesivity, conductivity, and antibacterial and antioxidant activities were developed by introducing cysteine-modified ε-poly(l-lysine) (ε-PL-SH) and in situ-polymerized polypyrrole (PPy) nanoparticles to induce full-thickness wound healing. CHLY hydrogels have a low swelling ratio, good compressive strength, and viscoelasticity due to chemical crosslinking, chelation, physical interaction, and nano-reinforcements in the matrix network of hydrogels. CHLY hydrogels possess excellent tissue adhesion ability, low cytotoxicity, enhanced cell migration ability, and good blood coagulation performance without causing hemolysis. Interestingly, the chemical conjugation of ε-PL-SH in the hydrogel matrix gives hydrogels an inherently robust and broad-spectrum antibacterial activity, while the introduction of PPy endows hydrogels with superior free radical scavenging capacity and good electroactivity. Significantly, CHLY hydrogels have advantages in alleviating persistent inflammatory response as well as promoting angiogenesis, epidermis regeneration, and orderly collagen deposition at the wound sites through their multi-functional synergies, thus effectively accelerating full-thickness wound healing and improving wound healing quality. Overall, our developed multi-functional collagen-based hydrogel dressing demonstrates promising application prospects in the field of tissue engineering to induce skin regeneration.


Asunto(s)
Hidrogeles , Polímeros , Hidrogeles/farmacología , Polímeros/farmacología , Pirroles/farmacología , Cicatrización de Heridas , Colágeno/farmacología , Antibacterianos/farmacología
10.
Int J Biol Macromol ; 226: 485-495, 2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36521695

RESUMEN

Microsphere with sphere-in-capsule structure is a multi-drugs delivery system to achieve the purpose of combination therapy. In this paper, we have prepared gelatin/alginate-based microspheres with sphere-in-capsule structure by a relatively fast, simple, and easily large-scale industrialized emulsification method for spatiotemporal manipulative drug release in gastrointestinal tract. Calcium alginate microspheres encapsulated with bovine serum albumin (BSA) were first prepared as inner microspheres, and then inner microspheres and ranitidine hydrochloride (RH) were co-encapsulated by gelatin microspheres to form double-layer microspheres with sphere-in-capsule structure. The size and distribution of microspheres can be easily controlled by emulsifying conditions. The microspheres with sphere-in-capsule structure displayed desirable encapsulation efficiency of BSA (61.52 %) and RH (56.07 %). The in vitro simulated drug release showed the spatiotemporal release feature of microspheres with sphere-in-capsule structure. In the specific simulated fluid, the release behavior and cumulative release of RH (sustainedly released 95 % in simulated gastric fluid) and BSA (rapidly released 73 % in simulated intestinal fluid) were different. The drug release mechanisms were analyzed to determine RH and BSA's release behavior. Overall, the microspheres with sphere-in-capsule structure have the potential application of spatiotemporal manipulative drug delivery in the gastrointestinal tract.


Asunto(s)
Alginatos , Gelatina , Microesferas , Gelatina/química , Alginatos/química , Liberación de Fármacos , Tracto Gastrointestinal , Albúmina Sérica Bovina/química , Tamaño de la Partícula
11.
Signal Transduct Target Ther ; 8(1): 247, 2023 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-37369642

RESUMEN

The extracellular matrix (ECM) serves as signals that regulate specific cell states in tumor tissues. Increasing evidence suggests that extracellular biomechanical force signals are critical in tumor progression. In this study, we aimed to explore the influence of ECM-derived biomechanical force on breast cancer cell status. Experiments were conducted using 3D collagen, fibrinogen, and Matrigel matrices to investigate the role of mechanical force in tumor development. Integrin-cytoskeleton-AIRE and DDR-STAT signals were examined using RNA sequencing and western blotting. Data from 1358 patients and 86 clinical specimens were used for ECM signature-prognosis analysis. Our findings revealed that ECM-derived mechanical force regulated tumor stemness and cell quiescence in breast cancer cells. A mechanical force of ~45 Pa derived from the extracellular substrate activated integrin ß1/3 receptors, stimulating stem cell signaling pathways through the cytoskeleton/AIRE axis and promoting tumorigenic potential and stem-like phenotypes. However, excessive mechanical force (450 Pa) could drive stem-like cancer cells into a quiescent state, with the removal of mechanical forces leading to vigorous proliferation in quiescent cancer stem cells. Mechanical force facilitated cell cycle arrest to induce quiescence, dependent on DDR2/STAT1/P27 signaling. Therefore, ECM-derived mechanical force governs breast cancer cell status and proliferative characteristics through stiffness alterations. We further established an ECM signature based on the fibrinogen/fibronectin/vitronectin/elastin axis, which efficiently predicts patient prognosis in breast cancer. Our findings highlight the vital role of ECM-derived mechanical force in governing breast cancer cell stemness/quiescence transition and suggest the novel use of ECM signature in predicting the clinical prognosis of breast cancer.


Asunto(s)
Integrinas , Neoplasias , Integrinas/genética , Línea Celular Tumoral , Matriz Extracelular/genética , Matriz Extracelular/metabolismo , Transducción de Señal/genética , Fibrinógeno/genética , Fibrinógeno/metabolismo , Neoplasias/metabolismo
12.
Carbohydr Polym ; 312: 120824, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37059551

RESUMEN

Diabetic chronic wound healing still faces huge clinical challenge. The arrangement and coordination of healing processes are disordered in diabetic wound caused by the persistent inflammatory response, microbial infection, impaired angiogenesis, resulting in the delayed and even non-healing wounds. Here, the dual-drug loaded nanocomposite polysaccharide-based self-healing hydrogels (OCM@P) with multifunctionality were developed to promote diabetic wound healing. Curcumin (Cur) loaded mesoporous polydopamine nanoparticles (MPDA@Cur NPs) and metformin (Met) were introduced into the polymer matrix formed by the dynamic imine bonds and electrostatic interactions between carboxymethyl chitosan and oxidized hyaluronic acid to fabricate OCM@P hydrogels. OCM@P hydrogels show homogeneous and interconnected porous microstructure, which possess good tissue adhesiveness, enhanced compression strength, great anti-fatigue behavior, excellent self-recovery capacity, low cytotoxicity, rapid hemostatic ability and robust broad-spectrum antibacterial activity. Interestingly, OCM@P hydrogels exhibit rapid release of Met and long-term sustained release of Cur, thereby to effectively scavenge extracellular and intracellular free radicals. Significantly, OCM@P hydrogels remarkably promote re-epithelization, granulation tissue formation, collagen deposition and arrangement, angiogenesis as well as wound contraction in diabetic wound healing. Overall, the multifunctional synergy of OCM@P hydrogels greatly contributes to accelerating diabetic wound healing, which demonstrate promising application as scaffolds in regenerative medicine.


Asunto(s)
Diabetes Mellitus , Hemostáticos , Humanos , Hidrogeles/química , Cicatrización de Heridas , Colágeno/farmacología , Hemostáticos/farmacología , Antibacterianos/farmacología
13.
Environ Sci Pollut Res Int ; 29(30): 46145-46160, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35157202

RESUMEN

The trend of economic decline for coal cities is a serious threat to the high-quality development of China's economy, and how to improve the environmental total factor productivity (ETFP) has become an urgent issue. Based on the framework of data envelopment analysis (DEA), this paper estimates ETFP using the global Malmquist-Luenberger productivity index (GMLPI). We decompose GMLPI into environmental technical efficiency change (ETEC) and the best practice gap change (BPGC). Then, the difference-in-difference (DID) model combining propensity score matching (PSM) method is used to investigate the effect of the Sustainable Development Plan of National Resource-based Cities (2013-2020) (SDP) aiming to improve ETFP. The results indicate that (1) On average, the GMLPI and BPGC are rising, while the ETEC is decreasing in the observed sample period; the western regions have the biggest BPGC, while the eastern regions have the biggest ETEC; (2) The SDP significantly improves the GMLPI and BPGC but has little effect on the ETEC; Coal cities located in eastern and central regions have policy effect, while the western regions do not have. (3) The SDP affects ETFP through slowing down the economic growth rate and reducing population agglomeration, but promoting the optimization of industrial structure. Those findings have policy implications for improving ETFP and promoting the industrial upgrade of coal cities.


Asunto(s)
Carbón Mineral , Eficiencia , China , Ciudades , Desarrollo Económico , Política Ambiental , Desarrollo Sostenible
14.
Artículo en Inglés | MEDLINE | ID: mdl-36078613

RESUMEN

The Transfer Payment Policy of National Key Ecological Functional Areas (TPEFAP), a well-known ecological compensation (eco-compensation) scheme in China, has been proposed by the government to alleviate ecological poverty and protect the environment. In literature, the effectiveness of the TPEFAP on environmental conservation has been widely examined, while few pay attention to the effect of the TPEFAP on poverty alleviation, especially with the consideration of its spatial spillovers as well. In this paper, we utilize panel data covering the key ecological functional areas of China during the period 2011-2018 to evaluate the impact of the TPEFAP on poverty alleviation and also its spatial spillovers by employing the synthetic control method (SCM) and the dynamic spatial Durbin model, respectively. Specifically, we apply the entropy weight method (EWM) to calculate the multidimensional poverty index (MPI) and measure pro-poor effect in terms of MPI change. The results show that: (1) TPEFAP has stable positive effects on MPI in Hubei, Yunnan, Jilin, Gansu, and Ningxia, while the impact on Qinghai fluctuates. (2) MPI presents a significant spatial correlation. Furthermore, both the direct and indirect effects of TPEFAP on MPI are significant and stable positive, for both short- or long-term. (3) For potential channels, rural non-farm employment, rural labor mobility, and agricultural productivity are the key pathways through which the TPEFAP can alleviate poverty both in local and adjacent provinces. However, it is difficult to find significant positive spatial spillovers for the TPEFAP if only the natural resources scale is considered. This study indicates that the government should pay attention to the policy expectations of ecological poverty alleviation and, in future eco-compensation, must further increase the coverage of subsidies and diversify the forms of subsidies.


Asunto(s)
Conservación de los Recursos Naturales , Pobreza , Agricultura , China , Humanos , Población Rural
15.
ACS Appl Bio Mater ; 5(2): 734-746, 2022 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-35094516

RESUMEN

Heterogeneous three-layer scaffolds were fabricated by mimicking the biochemical composition and structure of the hyaline cartilage, calcified cartilage, and subchondral bone of the osteochondral tissue for the repair of osteochondral defects. The hyaline cartilage layer was composed of collagen I (50.0 wt %) and sodium hyaluronate (50.0 wt %). The calcified cartilage layer and subchondral bone layer were composed of collagen I, sodium hyaluronate, and nanohydroxyapatite with different proportions. N-Hydroxysuccinimide/N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride was used to mediate the crosslinking reaction of the amine groups of collagen with carboxyl groups of sodium hyaluronate. The hyaline cartilage layer and calcified cartilage layer were designed as dense structures, while the subchondral bone layer was designed as a relatively loose structure by adjusting the crosslinking degree. The scaffolds displayed a uniform and interconnected porous structure and possessed a high porosity over 85%, which were conducive to cellular adhesion and proliferation. The scaffolds could remain at 50-75% after 30 days of degradation owing to crosslinking, providing enough time for the regeneration of the osteochondral tissue. Especially, the hyaline cartilage layer and calcified cartilage layer preferred to induce the proliferation of chondrocytes, while the subchondral bone layer was more conducive to the proliferation of osteoblasts. In conclusion, the heterogeneous multilayer scaffolds could serve as implant materials for osteochondral reconstruction.


Asunto(s)
Ingeniería de Tejidos , Andamios del Tejido , Colágeno/química , Cartílago Hialino , Ácido Hialurónico/farmacología , Andamios del Tejido/química
16.
Carbohydr Polym ; 285: 119237, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35287860

RESUMEN

Crosslinking is frequently used to improve the inherent poor physicochemical properties of collagen. However, local flocculation and irregular crosslinking of collagen would be unavoidably occurred once contacting with crosslinking agents due to widespread complex interactions. Herein, dialdehyde starch-based nanoparticles were developed to crosslink collagen as a new strategy. Starch was conjugated with cholesterol chloroformate before periodate oxidation to obtain dialdehyde cholesterol modified starch (DACS). DACS self-assembled into nanoparticles (DACSNPs) and crosslinked with collagen to fabricate collagen hydrogels (DACSNPs-Col). DACSNPs-Col hydrogels exhibited faster gelation rate, better uniform porous structure, higher mechanical properties and better degradation stability than dialdehyde starch crosslinked hydrogels. Significantly, DACSNPs-Col hydrogels show homogeneous structure, improved mechanical properties, low cytotoxicity, well blood compatibility, high cell adhesion and proliferation. Overall, the oxidized polysaccharide nanoparticles crosslinked collagen hydrogels have homogeneous and compact microstructure and improved physicochemical properties, which show potential application prospect in the field of tissue engineering scaffold.


Asunto(s)
Hidrogeles , Nanopartículas , Materiales Biocompatibles/química , Colesterol , Colágeno/química , Reactivos de Enlaces Cruzados/química , Hidrogeles/química , Hidrogeles/farmacología , Nanopartículas/química , Almidón/análogos & derivados , Almidón/química , Ingeniería de Tejidos/métodos
17.
Food Chem ; 387: 132885, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-35395481

RESUMEN

Food security is an important global public health issue, which will not only endanger consumers' life and health, but also cause serious food waste. Herein, antibacterial dialdehyde sodium alginate/ε-polylysine microspheres (DSA-PL MPs) were developed to effectively prolong the shelf life of fruit. DSA was prepared by periodate oxidation of sodium alginate. Then the PL was conjugated onto DSA backbone via the Schiff's base reaction to synthesize DSA-PL conjugates, followed by the emulsification and Ca2+ ions crosslinking to obtain DSA-PL MPs. The results indicate that DSA-PL MPs show smooth spherical particle, relatively narrow size distribution and good dispersity. In vitro degradation rate of DSA-PL MPs is higher in acetate buffer (pH = 5.0) than that in PBS buffer (pH = 7.4), showing acid-sensitive degradation property. Significantly, DSA-PL MPs possess strong broad-spectrum antibacterial activity, which can effectively extend the shelf life of fruit. Overall, DSA-PL MPs possess promising application as antibacterial agents for fruit preservation.


Asunto(s)
Polilisina , Eliminación de Residuos , Alginatos , Antibacterianos/química , Antibacterianos/farmacología , Frutas , Microesferas , Polilisina/química
18.
Carbohydr Polym ; 277: 118827, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34893244

RESUMEN

pH-Responsive nanoparticles (NPs) have emerged as an effective antitumor drug delivery system, promoting the drugs accumulation in the tumor and selectively releasing drugs in tumoral acidic microenvironment. Herein, we developed a new amphiphilic modified hydroxyethyl starch (HES) based pH-sensitive nanocarrier of antitumor drug delivery. HES was first modified by hydrophilic imidazole and hydrophobic cholesterol to obtain an amphiphilic polymer (IHC). Then IHC can self-assemble to encapsulate doxorubicin (DOX) and form doxorubicin-loaded nanoparticles (DOX/IHC NPs), which displayed good stability for one week storage and acidic sensitive long-term sustained release of DOX. As a result, cancer cell endocytosed DOX/IHC NPs could continuously release doxorubicin into cytoplasm and nucleus to effectively kill cancer cells. Additionally, DOX/IHC NPs could be effectively enriched in the tumor tissue, showing enhanced tumor growth inhibition effect compared to free doxorubicin. Overall, our amphiphilic modified HES-based NPs possess a great potential as drug delivery system for cancer chemotherapy.


Asunto(s)
Antibióticos Antineoplásicos/farmacología , Colesterol/química , Doxorrubicina/farmacología , Derivados de Hidroxietil Almidón/química , Imidazoles/química , Nanopartículas/química , Tensoactivos/química , Animales , Antibióticos Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/química , Portadores de Fármacos/química , Liberación de Fármacos , Ensayos de Selección de Medicamentos Antitumorales , Células Hep G2 , Humanos , Concentración de Iones de Hidrógeno , Neoplasias Hepáticas Experimentales/tratamiento farmacológico , Neoplasias Hepáticas Experimentales/metabolismo , Neoplasias Hepáticas Experimentales/patología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Tamaño de la Partícula , Células Tumorales Cultivadas
19.
ACS Appl Mater Interfaces ; 14(19): 21848-21859, 2022 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-35507826

RESUMEN

Transarterial radioembolization (TARE) is a promising technology in hepatocellular carcinoma (HCC) therapy, which utilizes radionuclide-labeled microspheres to achieve arterial embolization and internal irradiation. However, the therapeutic effect of liver cancer can be affected by low radionuclide labeling rate and stability, as well as poor biocompatibility, and non-biodegradability of microspheres. Here, 131I-labeled silk fibroin microspheres (131I-SFMs) were developed as radioembolization material for effective TARE therapy against HCC. Silk fibroin rich in 10.03% of tyrosine was extracted from silkworm cocoons and then emulsified and genipin-crosslinked to prepare SFMs. SFMs show a good settlement rate, biodegradability, hemocompatibility, and low cytotoxicity. Afterward, 131I-SFMs were obtained by radiolabeling 131I onto the SFMs through the chloramine-T method. 131I-SFMs possess a high 131I labeling rate of over 84% and good radioactive stability and are thus conducive to internal radiotherapy. Significantly, 131I-SFMs with diameters around 11 µm were successfully radioembolized at the hepatic artery. 131I-SFMs were diffused in the liver, indicating the favorable biodistribution and biosafety in vivo. Based on the combination of embolization and local radiotherapy, the administration of 131I-SFMs shows a favorable inhibitive effect against the progression of HCC. Overall, the newly developed 131I-SFMs as radioembolization microspheres provide a promising application for effective TARE therapy against liver cancer.


Asunto(s)
Carcinoma Hepatocelular , Fibroínas , Neoplasias Hepáticas , Animales , Carcinoma Hepatocelular/tratamiento farmacológico , Radioisótopos de Yodo , Neoplasias Hepáticas/tratamiento farmacológico , Microesferas , Ratas , Distribución Tisular , Radioisótopos de Itrio
20.
Int J Biol Macromol ; 202: 55-67, 2022 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-34998883

RESUMEN

Guided bone regeneration technique is an effective approach to repair bone defects, in which a barrier membrane is essential. However, the collagen barrier membranes commonly used lose stability quickly, leading to connective tissue invasion and failure of osteogenesis. Herein, we presented an oxidized sodium alginate (OSA)-collagen heterogeneous bilayer barrier membrane with well-controlled pore size and osteogenesis-promoting ability. The OSA crosslinking significantly improved the structural stability, compressive strength, swelling behavior, and slowed down the biodegradation rate of collagen membranes. Meanwhile, the collagen-based membranes exhibited superior cytocompatibility, osteogenesis-promotion, and barrier function against fibroblasts. Especially, the osteogenic differentiation was most promoted on the membrane with a large pore size (240-310 µm), while the barrier function was most improved on the membrane with a small pore size (30-60 µm). Then the above two membranes were combined together to obtain a heterogeneous bilayer membrane. This bilayer barrier membrane showed excellent osteogenesis-promoting ability in rats.


Asunto(s)
Alginatos , Osteogénesis , Alginatos/farmacología , Animales , Regeneración Ósea , Colágeno/química , Membranas , Membranas Artificiales , Ratas
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