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1.
Water Sci Technol ; 89(7): 1846-1859, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38619907

RESUMO

Geosynthetic clay liners (GCLs) are mostly used as flow barriers in landfills and waste containments due to their low hydraulic conductivity to prevent the leachate from reaching the environment. The self-healing and swell-shrink properties of soft clays (expansive soils) such as bentonite enable them as promising materials for the GCL core layers. However, it is important to modify their physico-chemical properties in order to overcome the functional limitations of GCL under different hydraulic conditions. In the present study, locally available black cotton soil (BCS) is introduced in the presence of an anionic polymer named carboxymethyl cellulose (CMC) as an alternative to bentonite to enhance the hydraulic properties of GCL under different compositions. The modified GCL is prepared by stitching the liner with an optimum percentage of CMC along with various percentages of BCS mixed with bentonite. Hydraulic conductivity tests were performed on the modified GCL using the flexi-wall permeameter. The results suggest that the lowest hydraulic conductivity of 4.58 × 10-10 m/s is obtained when 25% of BCS is blended with bentonite and an optimum 8% CMC and further addition of BCS results in the reduction of the hydraulic conductivity.


Assuntos
Bentonita , Eliminação de Resíduos , Bentonita/química , Argila , Solo , Metilcelulose , Eliminação de Resíduos/métodos , Carboximetilcelulose Sódica
2.
Chemosphere ; 355: 141726, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38521105

RESUMO

Polymer stabilization, exemplified by carboxymethyl cellulose (CMC), has demonstrated effectiveness in enhancing the transport of nanoscale zero-valent iron (nZVI). And, sulfidation is recognized for enhancing the reactivity and selectivity of nZVI in dechlorination processes. The influence of polymer stabilization on sulfidated nZVI (S-nZVI) with various sulfur precursors remains unclear. In this study, CMC-stabilized S-nZVI (CMC-S-nZVI) was synthesized using three distinct sulfur precursors (S2-, S2O42-, and S2O32-) through one-step approach. The antioxidant properties of CMC significantly elevated the concentration of reduced sulfur species (S2-) on CMC-S-nZVIs, marking a 3.1-7.0-fold increase compared to S-nZVIs. The rate of trichloroethylene degradation (km) by CMC-S-nZVIs was observed to be 2.2-9.0 times higher than that achieved by their non-stabilized counterparts. Among the three CMC-S-nZVIs, CMC-S-nZVINa2S exhibited the highest km. Interesting, while the electron efficiency of CMC-S-nZVIs surged by 7.9-12 times relative to nZVI, it experienced a reduction of 7.0-34% when compared with S-nZVIs. This phenomenon is attributed to the increased hydrophilicity of S-nZVI particles due to CMC stabilization, which inadvertently promotes the hydrogen evolution reaction (HER). In conclusion, the findings of this study underscores the impact of CMC stabilization on the properties and dechlorination performance of S-nZVI sulfidated using different sulfur precursors, offering guidance for engineering CMC-S-nZVIs with desirable properties for contaminated groundwater remediation.


Assuntos
Água Subterrânea , Tricloroetileno , Poluentes Químicos da Água , Carboximetilcelulose Sódica , Ferro , Enxofre , Polímeros
3.
Int J Biol Macromol ; 265(Pt 2): 131133, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38537851

RESUMO

The low chrome uptake by collagen in the conventional tanning process leads to the pollution of the wastewater. Due to environmental concerns, leather scientists are already searching for innovative ways to produce pre-tanning agents as a high exhaustion chrome tanning auxiliary. Herein, a novel kind of pre-tanning agent is engineered by converting carboxymethyl cellulose (CMC) to oxidized carboxymethyl cellulose (OCMC) via the hydrogen peroxide process. FT-IR and carboxyl content analysis demonstrated the increase in carboxyl content after oxidation. After that, the obtained OCMC was utilized as a pre-tanning agent, resulting in a high exhaustion of chrome (92.76 %) which is 27.76 % more than conventional chrome tanning (65 %), and the amount of chrome in wastewater reduced to 7.24 %. The hydrothermal stability of wet-blue increased by increasing the uptake of chrome (Ts = 118 °C). The obtained crust leather represented excellent mechanical properties (Tensile strength: 305.68 kg/cm2; tear strength: 50 kg/cm) and desirable organoleptic properties. The environmental analysis signifies a significant step towards a cleaner and sustainable tanning process (COD = 1600, BOD5 = 560 mg/L) compared to the conventional chrome tanning process. Consequently, the obtained results offer a green pre-tanning agent to meet the requirements of the sustainable development of the leather industry.


Assuntos
Carboximetilcelulose Sódica , Curtume , Peróxidos , Espectroscopia de Infravermelho com Transformada de Fourier , Águas Residuárias , Resíduos Industriais/análise , Cromo
4.
Int J Biol Macromol ; 265(Pt 1): 130466, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38432274

RESUMO

A novel colorimetric aerogel was developed by the complexation of carboxymethyl cellulose (CMC), sodium alginate (SA), and black goji anthocyanin (BGA) followed by freeze-drying for monitoring fish (Coho salmon) freshness during storage at 4 °C and 25 °C. The various aerogels (C/S/B3:1, C/S/B2:1, C/S/B1:1, C/S/B1:2, and C/S/B1:3) externally and internally were characterized using SEM, FTIR, XRD, DSC, and TGA. Among them, the aerogel composite C/S/B1:2 exhibited the most uniform pore size, largest specific surface area, rapid color changes in various alkaline vapors (5 µM and 50 µM), and better mechanical strength. Furthermore, the colorimetric aerogel became dark blue from light purple during fish storage at temperatures of 4 °C and 25 °C when it reached pH 7.49 and 7.33, TVC 8.9 × 107 CFU/g and 8.5 × 107 CFU/g, and TVB-N 33.8 mg/100 g and 26.12 mg/100 g, respectively, indicating fish completely deteriorated. Taken together, the colorimetric aerogel composite C/S/B1:2 was promising for determining fish freshness, which could be utilized as a non-destructive and useful intelligent sensor in monitoring various fish and meat freshness and/or quality.


Assuntos
Alginatos , Carboximetilcelulose Sódica , Animais , Carboximetilcelulose Sódica/química , Antocianinas/química , Colorimetria , Embalagem de Alimentos
5.
Biomater Sci ; 12(8): 2067-2085, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38470831

RESUMO

The extracellular matrix (ECM) presents a framework for various biological cues and regulates homeostasis during both developing and mature stages of tissues. During development of cartilage, the ECM plays a critical role in endowing both biophysical and biochemical cues to the progenitor cells. Hence, designing microenvironments that recapitulate these biological cues as provided by the ECM during development may facilitate the engineering of cartilage tissue. In the present study, we fabricated an injectable interpenetrating hydrogel (IPN) system which serves as an artificial ECM and provides chondro-inductive niches for the differentiation of stem cells to chondrocytes. The hydrogel was designed to replicate the gradual stiffening (as a biophysical cue) and the presentation of growth factors (as a biochemical cue) as provided by the natural ECM of the tissue, thus exemplifying a biomimetic approach. This dynamic stiffening was achieved by incorporating silk fibroin, while the growth factor presentation was accomplished using sulfated-carboxymethyl cellulose. Silk fibroin and sulfated-carboxymethyl cellulose (s-CMC) were combined with tyraminated-carboxymethyl cellulose (t-CMC) and crosslinked using HRP/H2O2 to fabricate s-CMC/t-CMC/silk IPN hydrogels. Initially, the fabricated hydrogel imparted a soft microenvironment to promote chondrogenic differentiation, and with time it gradually stiffened to offer mechanical support to the joint. Additionally, the presence of s-CMC conferred the hydrogel with the property of sequestering cationic growth factors such as TGF-ß and allowing their prolonged presentation to the cells. More importantly, TGF-ß loaded in the developed hydrogel system remained active and induced chondrogenic differentiation of stem cells, resulting in the deposition of cartilage ECM components which was comparable to the hydrogels that were treated with TGF-ß provided through media. Overall, the developed hydrogel system acts as a reservoir of the necessary biological cues for cartilage regeneration and simultaneously provides mechanical support for load-bearing tissues such as cartilage.


Assuntos
Cartilagem Articular , Fibroínas , Engenharia Tecidual/métodos , Hidrogéis/química , Sulfatos , Carboximetilcelulose Sódica , Peróxido de Hidrogênio , Cartilagem , Seda , Fator de Crescimento Transformador beta , Tecidos Suporte/química , Condrogênese
6.
Int J Biol Macromol ; 265(Pt 1): 130849, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38484807

RESUMO

This study aimed to enhance carboxymethyl cellulose (CMC)-based films by incorporating zinc oxide nanoparticles (ZnO NPs) and cress seed mucilage (CSM), with a view to augmenting the physical, mechanical, and permeability properties of the resulting nanocomposite films. For the first time, CSM was exploited as a green surfactant to synthetize ZnO NPs using hydrothermal method. Seven distinct film samples were meticulously produced and subjected to a comprehensive array of analyses. The findings revealed that the incorporation of CSM/ZnO-5 % improved the physical properties of the films, demonstrating a significant reduction in moisture content and water vapor permeability (WVP). Increasing the concentration of NPs in conjunction with CSM markedly decreased the solubility of the nanocomposites by up to 56 %. The films containing CSM/ZnO showed higher tensile strength and elongation at the break values. The UV absorption of the films exhibited a substantial rise with the addition of ZnO NPs, particularly with an increased content in the presence of CSM. The thermal stability of nanocomposites containing a high concentration of CSM/ZnO exhibited an improvement compared to the control sample. In light of these results, the CMC/CSM/ZnO-5 % film emerges as a promising candidate for a biocompatible packaging material, exhibiting favorable physical characteristics.


Assuntos
Brassicaceae , Nanocompostos , Nanopartículas , Óxido de Zinco , Antibacterianos , Carboximetilcelulose Sódica , Tensoativos , Polissacarídeos , Materiais Biocompatíveis , Verduras
7.
Carbohydr Polym ; 334: 122014, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38553214

RESUMO

Currently, adhesive hydrogels have shown promising effect in chronic diabetic wound repair. However, there are issues and challenges in treating diabetic wounds due to inadequate wet adhesion, unable to fill irregular and deep wounds, and oxidative stress. Herein, a mussel-inspired naturally hydrogel dressing with rapid shape adaptability, wet adhesion and antioxidant abilities for irregular, deep and frequently movement diabetic wounds repair was constructed by comprising catechol modified carboxymethyl cellulose (CMC-DA) and tannic acid. Benefiting from the reversible hydrogen bonding, the resulting hydrogels exhibited injectability, remarkable self-healing ability, rapid shape adaptability and strong tissue adhesion (45.9 kPa), thereby contributing to self-adaptive irregular-shaped wounds or moving joint parts. Especially, the adhesion strength of the hydrogel on wet tissue still remained at 14.9 kPa. Besides, the hydrogels could be easily detached from the skin by ice-cooling that avoided secondary damage caused by dressing change. Remarkably, the hydrogels possessed excellent antioxidant, satisfactory biocompatibility, efficient hemostasis and antibacterial properties. The in vivo evaluation further demonstrated that the hydrogel possessed considerable wound-healing promotion effect by regulating diabetic microenvironment, attributed to that the hydrogel could significantly reduce inflammatory response, alleviate oxidative stress and regulate neovascularization. Overall, this biosafe adhesive hydrogel had great potentials for diabetic wound management.


Assuntos
Antioxidantes , Diabetes Mellitus , Polifenóis , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Hidrogéis/farmacologia , Carboximetilcelulose Sódica/farmacologia , Estresse Oxidativo , Antibacterianos
8.
Carbohydr Polym ; 334: 122020, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38553219

RESUMO

Zinc oxide nanostructures (ZnO NS) were fabricated in situ within a ternary hydrogel system composed of carboxymethyl cellulose-agarose-polyvinylpyrrolidone (CAP@ZnO TNCHs) by a one-pot method employing moist-heat solution casting. The percentages of CMC and ZnO NS were varied in the CAP hydrogel films and then they were investigated by different techniques, such as ATR/FTIR, TGA, XRD, XPS, and FE-SEM analysis. Furthermore, the mechanical properties, hydrophilicity, swelling, porosity, and antibacterial activity of the CAP@ZnO TNCHs were studied. In-vitro biocompatibility assays were performed with skin fibroblast (CCD-986sk) cells. In-vitro culture of CCD-986sk fibroblasts showed that the ZnO NS facilitated cell adhesion and proliferation. Furthermore, the application of CAP@ZnO TNCHs enhanced cellular interactions and physico-chemical, antibacterial bacterial, and biological performance relative to unmodified CAP hydrogels. Also, an in vivo wound healing study verified that the CAP@ZnO TNCHs promoted wound healing significantly within 18 days, an effect superior to that of unmodified CAP hydrogels. Hence, these newly developed cellulose-based ZnO TNCHs are promising materials for wound healing applications.


Assuntos
Nanoestruturas , Óxido de Zinco , Hidrogéis/farmacologia , Hidrogéis/química , Óxido de Zinco/farmacologia , Óxido de Zinco/química , Carboximetilcelulose Sódica/química , Antibacterianos/química , Nanoestruturas/química , Cicatrização
9.
Carbohydr Polym ; 334: 122041, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38553238

RESUMO

Recently, there has been a focus on using biopolymer-based particles to stabilize high internal phase Pickering emulsions (HIPPEs) due to the notable advances in biocompatibility and biodegradability. In this work, the complex particles of peanut protein isolate and carboxymethyl cellulose (CMC) with various substitution degrees (DS; 0.7 and 0.9) and weight average molecular weights (Mw; 90, 250, and 700 kDa) were prepared and characterized as novel stabilizers. For the obtained four types of morphologically distinct particles, the complex particles formed by CMC (0.9 DS and 250 kDa) showed cluster structures with an average size of 1.271 µm, equally biphasic wettability with three-phase contact angles of 91.5°, and the highest diffusion rate at the oil-water interface. HIPPEs stabilized by these particles exhibited more elastic behavior due to the smaller tanδ and higher viscosity, as well as excellent thixotropic recovery properties and stability against heating, storage, and freeze-thawing. Furthermore, confocal laser scanning microscopy verified that these particles formed a dense interfacial layer around the oil droplets, which could resist flocculation and coalescence between oil droplets during in vitro digestion. The improved bioaccessibility of curcumin-loaded HIPPEs made these delivery systems potentially apply in functional foods.


Assuntos
Curcumina , Emulsões/química , Curcumina/química , Carboximetilcelulose Sódica , Molhabilidade , Reologia , Tamanho da Partícula
10.
Biosens Bioelectron ; 254: 116228, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38522233

RESUMO

Detection of superoxide anion (O2·-) levels holds significant importance for the diagnosis and even clinical treatments of oxidative stress-related diseases. Herein, we prepared a composite electrode material to encapsulate copper-zinc superoxide dismutase (SOD1) for biosensing of O2·-. The sensing material consists of gold nanowires (AuNWs), reduced graphene oxide (rGO), carboxymethyl cellulose (CMC) and PEDOT:PSS. CMC provides abundant -COOH to bind SOD1, with a high adsorption coverage of 1.499 × 10-9 mol cm-2 on the sensor surface. rGO and PEDOT endow the composite with significant conductivity, whereas PSS has antifouling capability. Moreover, AuNWs exhibit excellent electrical conductivity and a high aspect ratio, which promotes electron transfer, and ultimately enhances the catalytic performance of the enzyme. Meanwhile, SOD1(Cu2+) catalyzes the dismutation of O2·- to O2 and H2O2, and H2O2 is then electrochemically oxidized to generate amperometric signals for determination of O2·-. The sensor demonstrates outstanding detection performance for O2·- with a low detection limit of 2.52 nM, and two dynamic ranges (14.30 nM-1.34 µM and 1.34 µM-42.97 µM) with corresponding sensitivity of 0.479 and 0.052 µA µM-1cm-2, respectively. Additionally, the calculated apparent Michaelis constant (Kmapp) of 1.804 µM for SOD1 demonstrates the outstanding catalytic activity and the surface-immobilized enzyme's substrate affinity. Furthermore, the sensor shows the capability to dynamically detect the level of O2·- released from living HepG2 cells. This study provides an inovative design to obtain a biocompatible electrochemical sensing platform with plenty of immobilization sites for biomolecules, large surface area, high conductivity and flexibility.


Assuntos
Técnicas Biossensoriais , Grafite , Superóxidos/química , Carboximetilcelulose Sódica , Peróxido de Hidrogênio , Superóxido Dismutase-1 , Técnicas Biossensoriais/métodos , Grafite/química , Superóxido Dismutase/química , Técnicas Eletroquímicas
11.
Carbohydr Polym ; 333: 121987, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38494238

RESUMO

Limited bone regeneration, uncontrollable degradation rate, mismatched defect zone and poor operability have plagued the reconstruction of irregular bone defect by tissue-engineered materials. A combination of biomimetic scaffolds with hydroxyapatite has gained great popularity in promoting bone regeneration. Therefore, we designed an injectable, photocurable and in-situ curing hydrogel by methacrylic anhydride -modified carboxymethyl cellulose (CMC-MA) loading with spherical hydroxyapatite (HA) to highly simulate the natural bony matrix and match any shape of damaged tissue. The prepared carboxymethyl cellulose-methacrylate/ hydroxyapatite(CMC-MA/HA) composite presented good rheological behavior, swelling ratio and mechanical property under light illumination. Meanwhile, this composite hydrogel promoted effectively proliferation, supported adhesion and upregulated the osteogenic-related genes expression of MC3T3-E1 cells in vitro, as well as the activity of the osteogenic critical protein, Integrin α1, ß1, Myosin 9, Myosin 10, BMP-2 and Smad 1 in Integrin/BMP-2 signal pathway. Together, the composite hydrogels realized promotion of bone regeneration, deformity improvement, and the enhanced new bone strength in skull defect. It also displayed a good histocompatibility and stability of subcutaneous implantation in vivo. Overall, this study laid the groundwork for future research into developing a novel biomaterial and a minimally invasive therapeutic strategies for reconstructing bone defects and contour deficiencies.


Assuntos
Durapatita , Tecidos Suporte , Carboximetilcelulose Sódica , Crânio , Hidrogéis/farmacologia , Miosinas
12.
Colloids Surf B Biointerfaces ; 236: 113827, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38430830

RESUMO

In this study, cross-linked carboxymethyl cellulose/chitosan submicron particles were employed to facilitate the stabilization of Pickering emulsion. The polymer particles were prepared using the polyelectrolyte self-assembly method in conjunction with isocyanide based multicomponent reactions and the characteristics were obtained using: nuclear magnetic resonance, Fourier-transform infrared spectroscopy and dynamic light scattering. Atomic force microscopy revealed the heterogeneous structure of the resulting submicron particles with domains of 20-30 nm in size. The average diameter was found to be in the range of 229-378 nm and they were found to be suitable for the fabrication of oil/water Pickering emulsion when proceeded via the homogenization method followed by sonication. The results obtained revealed that carboxymethyl cellulose/chitosan particles significantly stabilized the droplets at the oil/water interface. Even at low particle concentrations of 0.3 g/L (which is close to that of low molecular weight surfactants) stable Pickering emulsions have been obtained. Additionally, the resulting emulsions showed a high level of stability with regard to changes in pH, temperature and ionic strength. The natural alkaloid piperine was used as a model compound to load the resulting particles, which possessed encapsulation efficiency of 90.6±0.4%. Furthermore, the in vitro release profile of piperine from the Pickering emulsion revealed a much-controlled release in both acidic and neutral media as compared to the unformulated piperine. Additional findings in this work revealed important information on the application of carboxymethyl cellulose/chitosan submicron particles as Pickering stabilizers for creation of new delivery systems.


Assuntos
Alcaloides , Benzodioxóis , Quitosana , Nanopartículas , Piperidinas , Alcamidas Poli-Insaturadas , Quitosana/química , Emulsões/química , Celulose/química , Carboximetilcelulose Sódica , Polímeros , Emulsificantes , Tamanho da Partícula , Nanopartículas/química
13.
Carbohydr Polym ; 332: 121915, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38431395

RESUMO

This study aimed to explore an innovative approach to enhancing the shelf-life and quality of meat products through the application of an active packaging system. The study involved the development of new free-standing carboxymethyl cellulose (CMC) nanocomposite films incorporated with nanoencapsulated flavonoids derived from pomegranate extract. The loaded flavonoids, known for their antioxidant and antimicrobial properties, were nanoencapsulated via a self-assembly approach in a mixture of chitosan and sodium alginate to improve their stability, solubility, and controlled release characteristics. Chemical structure, size, and morphology of the obtained nanoparticles (Pg-NPs) were studied with FTIR, zeta-sizer, and TEM. The Pg-NPs showed particle size of 232 nm, and zeta-potential of -20.7 mV. Various free-standing nanocomposite films were then developed via incorporation of Pg-NPs into CMC-casted films. FTIR, SEM, thermal and mechanical properties, and surface wettability were intensively studied for the nanocomposite films. Barrier properties against water vapor were investigated at 2022 g·m-2d-1. The nanocomposite films possessed superior properties for inhibiting bacterial growth and extending the shelf-life of beef and poultry meat for 12 days compared with the Pg-NPs-free CMC films. This study presented a promising approach for development of active packaging systems with improved antimicrobial and antioxidant properties, and economic and environmental impacts.


Assuntos
Anti-Infecciosos , Punica granatum , Animais , Bovinos , Carboximetilcelulose Sódica/química , Embalagem de Alimentos , Antioxidantes/farmacologia , Antioxidantes/química , Carne/microbiologia , Anti-Infecciosos/farmacologia , Flavonoides
14.
Carbohydr Polym ; 332: 121925, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38431419

RESUMO

Carboxymethyl cellulose (CMC) is a well-known cellulose derivative used in biomedical applications due to its biocompatibility and biodegradability. In this work, novel porous CMC materials, aerogels, were prepared and tested as a drug delivery device. CMC aerogels were made from CMC solutions, followed by non-solvent induced phase separation and drying with supercritical CO2. The influence of CMC characteristics and of processing conditions on aerogels' density, specific surface area, morphology and drug release properties were investigated. Freeze-drying of CMC solutions was also used as an alternative process to compare the properties of the as-obtained "cryogels" with those of aerogels. Aerogels were nanostructured materials with bulk density below 0.25 g/cm3 and high specific surface area up to 143 m2/g. Freeze drying yields highly macroporous materials with low specific surface areas (around 5-18 m2/g) and very low density, 0.01 - 0.07g/cm3. Swelling and dissolution of aerogels and cryogels in water and in a simulated wound exudate (SWE) were evaluated. The drug was loaded in aerogels and cryogels, and release kinetics in SWE was investigated. Drug diffusion coefficients were correlated with material solubility, morphology, density, degree of substitution and drying methods, demonstrating tuneability of new materials' properties in view of their use as delivery matrices.


Assuntos
Carboximetilcelulose Sódica , Criogéis , Géis , Sistemas de Liberação de Medicamentos , Celulose
15.
Vaccine ; 42(9): 2394-2406, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38448321

RESUMO

Malaria caused byPlasmodium vivaxis a pressing public health problem in tropical and subtropical areas.However, little progress has been made toward developing a P. vivaxvaccine, with only three candidates being tested in clinical studies. We previously reported that one chimeric recombinant protein (PvCSP-All epitopes) containing the conserved C-terminus of the P. vivax Circumsporozoite Protein (PvCSP), the three variant repeat domains, and aToll-like receptor-3 agonist,Poly(I:C), as an adjuvant (polyinosinic-polycytidylic acid, a dsRNA analog mimicking viral RNA), elicits strong antibody-mediated immune responses in mice to each of the three allelic forms of PvCSP. In the present study, a pre-clinical safety evaluation was performed to identify potential local and systemic toxic effects of the PvCSP-All epitopes combined with the Poly-ICLC (Poly I:C plus poly-L-lysine, Hiltonol®) or Poly-ICLC when subcutaneously injected into C57BL/6 mice and New Zealand White Rabbits followed by a 21-day recovery period. Overall, all observations were considered non-adverse and were consistent with the expected inflammatory response and immune stimulation following vaccine administration. High levels of vaccine-induced specific antibodies were detected both in mice and rabbits. Furthermore, mice that received the vaccine formulation were protected after the challenge with Plasmodium berghei sporozoites expressing CSP repeats from P. vivax sporozoites (Pb/Pv-VK210). In conclusion, in these non-clinical models, repeated dose administrations of the PvCSP-All epitopes vaccine adjuvanted with a Poly-ICLC were immunogenic, safe, and well tolerated.


Assuntos
Carboximetilcelulose Sódica/análogos & derivados , Vacinas Antimaláricas , Malária Vivax , Polilisina/análogos & derivados , Camundongos , Animais , Coelhos , Malária Vivax/prevenção & controle , Poli I-C , Plasmodium vivax , Proteínas de Protozoários/genética , Camundongos Endogâmicos C57BL , Adjuvantes Imunológicos , Proteínas Recombinantes , Epitopos , Anticorpos Antiprotozoários
16.
Surgery ; 175(5): 1358-1367, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38429164

RESUMO

BACKGROUND: We aimed to evaluate the incidence of postoperative adhesion formation and adhesion-related consequences (eg, bowel obstruction) after placement of a sodium hyaluronate-carboxymethylcellulose adhesion barrier after laparoscopic abdominopelvic surgery. METHODS: In this systematic review and meta-analysis, we searched the Medical Literature Analysis and Retrieval System Online and Embase via Ovid, Cochrane Central Register of Controlled Trials, ScienceDirect, BIOSIS Previews, Cumulative Index to Nursing and Allied Health Literature, and Clinical Trial Registries. A manual search (eg, Google Scholar and professional association websites) was also conducted to supplement the electronic database results. Two reviewers independently identified relevant studies based on inclusion and exclusion criteria and extracted data. RESULTS: A total of 28 studies were included in the systematic qualitative review. Three of the 28 studies included had comparable outcome measures, interventions, and control groups, allowing the pooling of study data. A total of 938 patients (490 patients in the sodium hyaluronate-carboxymethylcellulose barrier group and 448 in the no adhesion barrier group) from these 3 studies were included in the meta-analyses, which found the incidence of bowel obstruction was significantly lower (65% risk reduction) in the sodium hyaluronate-carboxymethylcellulose barrier group compared with the control group (relative risk = 0.35; 95% confidence interval, 0.19-0.63; P = .005) with extremely low heterogeneity between studies (I2 = 0; P = .41). The placement of sodium hyaluronate-carboxymethylcellulose barrier laparoscopically did not create new safety signals nor did it increase the incidence of adverse events. CONCLUSION: Our meta-analysis found that laparoscopic application of a sodium hyaluronate-carboxymethylcellulose barrier in abdominopelvic surgery reduces the risk of bowel obstruction where applied during the early postoperative phase.


Assuntos
Obstrução Intestinal , Laparoscopia , Humanos , Ácido Hialurônico/uso terapêutico , Carboximetilcelulose Sódica/uso terapêutico , Revisões Sistemáticas como Assunto , Laparoscopia/efeitos adversos , Aderências Teciduais/epidemiologia , Aderências Teciduais/etiologia , Aderências Teciduais/prevenção & controle , Metanálise como Assunto
17.
Int J Biol Macromol ; 264(Pt 2): 130572, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38447825

RESUMO

To effectively extend the shelf life of fruits meanwhile facilitating consumers to judge their freshness, in this work, a double-layer multifunctional film combining CO2 sensitivity and antibacterial properties was successfully prepared by adding methyl red (MR), bromothymol blue (BTB) into gellan gum (GG) as the sensing inner layer, and doping tannic acid (TA) into sodium alginate with sodium carboxymethyl cellulose (CMC) as the antimicrobial outer layer, which was applied to the freshness indication of strawberries. Microscopic morphology and spectral analysis demonstrated that the bi-layer films were fabricated successfully. The mechanical characteristics, thermal stability, water vapor resistance, and antibacterial capabilities of the bilayer films improved as TA concentration rose. They exhibited noticeable color changes at pH = 2-10 and different concentrations of CO2. Application of the prepared films to strawberries revealed that the GG-MB@SC-6%TA film performed most favorably under 4 °C storage conditions, not only monitoring strawberry freshness but also retaining high soluble solids and titratable acidity, resulting in a slight decrease in hardness and weight loss. Therefore, taking into account all of the physical-functional characteristics, the GG-MB@6%TA film has a broad application prospect for intelligent food packaging.


Assuntos
Anti-Infecciosos , Fragaria , Polifenóis , Polissacarídeos Bacterianos , Dióxido de Carbono , Carboximetilcelulose Sódica/química , Alginatos , Antibacterianos/farmacologia , Antibacterianos/química , Embalagem de Alimentos/métodos , Sódio
18.
Food Chem ; 447: 139028, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38513483

RESUMO

In this study, a carboxymethylcellulose (CMC) induced depletion attraction was developed to stabilize high internal phase Pickering emulsions (HIPPEs) as age-friendly 3D printing inks. The results demonstrated that depletion force induced the adsorption of yolk particles at the droplet interface and the formation of osmotic droplet clusters, thereby increasing the stability of HIPPEs. In addition, the rheological properties and nutrient delivery properties of HIPPEs could be adjusted by the mass ratio of yolk/CMC. The HIPPEs stabilized at yolk/CMC mass ratio 20:7.5 showed optimal printability, viscoelastic, structural recovery, and swallowability. HIPPEs have been applied to 3D printing, International Dysphagia Dietary Standardization Initiative (IDDSI) test, and in vitro digestive simulation in the elderly, indicating their attractive appearance, safe swallowability, and enhanced bioaccessibility of ß-carotene. Our work provides new ideas for developing age-friendly foods with plasticity and nutrient delivery capacity by depletion attraction stabilizing HIPPEs.


Assuntos
Carboximetilcelulose Sódica , beta Caroteno , Idoso , Humanos , Emulsões , Adsorção , Impressão Tridimensional , Tamanho da Partícula
19.
Int J Biol Macromol ; 264(Pt 1): 130565, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38432268

RESUMO

Healing chronic and critical-sized full-thickness wounds is a major challenge in the healthcare sector. Scaffolds prepared using electrospinning and hydrogels serve as effective treatment options for wound healing by mimicking the native skin microenvironment. Combining synthetic nanofibers with tunable hydrogel properties can effectively overcome limitations in skin scaffolds made only with nanofibers or hydrogels. In this study, a biocompatible hybrid scaffold was developed for wound healing applications using poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) nanofibers embedded with hydrogel made of 2 % carboxymethyl cellulose (CMC) blended with 1 % agarose. Hybrid scaffolds, characterized for surface morphology, swellability, porosity, and degradation, were found to be suitable for wound healing. Furthermore, the incorporation of CMC-agarose hydrogel into nanofibers significantly enhanced their mechanical strength compared to PHBV nanofibers alone (p < 0.05). Extract cytotoxicity and direct cytotoxicity tests showed that the hybrid scaffolds developed in this study are cytocompatible (>75 % viability). Furthermore, human adult dermal fibroblasts (HDFa) and human adult immortalized keratinocytes (HaCaT) adhesion, viability, and proliferation studies revealed that the hybrid scaffolds exhibited a significant increase in cell proliferation over time, similar to PHBV nanofibers. Finally, the developed hybrid scaffolds were evaluated in rat full-thickness wounds, demonstrating their ability to promote full-thickness wound healing with reepithelialization and epidermis closure.


Assuntos
Nanofibras , Poli-Hidroxibutiratos , Tecidos Suporte , Ratos , Humanos , Animais , Carboximetilcelulose Sódica , Sefarose , Transplante de Pele , Hidrogéis/farmacologia , Poliésteres , Hidroxibutiratos
20.
Int J Biol Macromol ; 263(Pt 1): 130302, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38382794

RESUMO

In this study, dialdehyde carboxymethyl cellulose (DCMC, 10 wt% based on gelatin) and varying contents of coffee leaf extract (CLE, 1, 3, 5 and 7 wt% based on gelatin) were incorporated into gelatin (GEL) matrix to develop multifunctional food packaging films. DCMC acted as a physical reinforcing filler through crosslinking with GEL matrix by Schiff-base reaction, CLE served as an active filler to confer film functional properties. The micro-morphology, micro-structure, physicochemical and functional properties of the GEL/DCMC/CLE composite film were investigated. The results demonstrated that mechanical, barrier properties and thermal stability of films were significantly improved by incorporation of CLE. Compared with pure GEL film, the GEL/DCMC/5%CLE film exhibited excellent UV light blocking while kept enough transparency, the best mechanical property, water resistance, water vapor and oxygen barrier, as well as thermal stability. GEL/DCMC/5%CLE film also possessed strong antioxidant activity and some antibacterial activity against E. coli and S. aureus. Packaging application testing demonstrated that the resultant GEL/DCMC/5%CLE film effectively delayed the lipid oxidation of walnut oil and preserved the postharvest freshness of fresh walnut kernels under ambient conditions.


Assuntos
Carboximetilcelulose Sódica , Embalagem de Alimentos , Carboximetilcelulose Sódica/química , Gelatina/química , Escherichia coli , Staphylococcus aureus , Extratos Vegetais/farmacologia
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