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1.
Ecotoxicol Environ Saf ; 202: 110935, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800218

RESUMO

This study investigated the ability of dual crosslinked interpenetrating polymer network (IPN) blend beads (DIN:SA/PVA-beads), composed of sodium alginate (SA) and poly (vinyl alcohol) (PVA), as a base-triggered carrier for the controlled release of dinotefuran (DIN) in Spodoptera litera midgut. The blend beads were characterized for morphology, encapsulation efficiency, swelling degree, and in vitro release of the blend beads were characterized. The results revealed that the double-crosslinked gel beads had a tightly interpenetrating network structure and exhibited a satisfactory embedding effect for DIN. The maximum of the DIN loading capacity was approximately 1.01%, with a high encapsulation efficiency of 83.19%. The triggered release of DIN from the blend beads was studied in deionized water (pH 3.0-11.0) via high-performance liquid chromatography (HPLC); it was found that the release rate was higher in alkaline pH conditions than in acidic and neutral conditions. An in vivo dynamics and degradation study also demonstrated that the excellent release characteristics of DIN:SA/PVA-beads in the midgut of S. litera. This study provides a promising controlled-release form of dinotefuran that is more effective and can be used for the targeted control of pests with alkaline midgut.


Assuntos
Guanidinas/metabolismo , Neonicotinoides/metabolismo , Nitrocompostos/metabolismo , Spodoptera/metabolismo , Alginatos/química , Animais , Preparações de Ação Retardada/química , Etanol , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Hidrogéis/química , Concentração de Íons de Hidrogênio , Polímeros , Álcool de Polivinil/química
2.
Int J Nanomedicine ; 15: 4959-4967, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764929

RESUMO

Background: Particle-based drug delivery systems (DDSs) have a demonstrated value for drug discovery and development. However, some problems remain to be solved, such as limited stimuli, visual-monitoring. Aim: To develop an intelligent multicolor DDSs with both near-infrared (NIR) controlled release and macroscopic color changes. Materials and Methods: Microparticles comprising GO/pNIPAM/PEGDA composite hydrogel inverse opal scaffolds, with dextran and calcium alginate hydrogel were synthesized using SCCBs as the template. The morphology of microparticle was observed under scanning electron microscopy, and FITC-dextran-derived green fluorescence images were determined using a confocal laser scanning microscope. During the drug release, FITC-dextran-derived green fluorescence images were captured using fluorescent inverted microscope. The relationship between the power of NIR and the drug release rate was obtained using the change in optical density (OD) values. Finally, the amount of drug released could be estimated quantitatively used the structural color or the reflection peak position. Results: A fixed concentration 8% (v/v) of PEGDA and 4mg/mL of GO was chosen as the optimal concentration based on the balance between appropriate volume shrinkage and structure color. The FITC-dextran was uniformly encapsulated in the particles by using 0.2 wt% sodium alginate. The microcarriers shrank because of the photothermal response and the intrinsic fluorescence intensity of FITC-dextran in the microparticles gradually decreased at the same time, indicating drug release. With an increasing duration of NIR irradiation, the microparticles gradually shrank, the reflection peak shifted toward blue and the structural color changed from red to orange, yellow, green, cyan, and blue successively. The drug release quantity can be predicted by the structural color of microparticles. Conclusion: The multicolor microparticles have great potential in drug delivery systems because of its vivid reporting color, excellent photothermal effect, and the good stimuli responsivity.


Assuntos
Portadores de Fármacos/química , Microesferas , Resinas Acrílicas/química , Alginatos/química , Cor , Dextranos/química , Liberação Controlada de Fármacos , Fluoresceína-5-Isotiocianato/análogos & derivados , Fluoresceína-5-Isotiocianato/química , Hidrogéis/química , Fenômenos Ópticos , Polietilenoglicóis/química
3.
Int J Nanomedicine ; 15: 5097-5111, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764939

RESUMO

Introduction: In this in-vitro study, we designed a 3D printed composite of zinc oxide (ZnO) nanoparticles (NPs) with photocatalytic activities encapsulated within hydrogel (alginate) constructs, for antibacterial purposes applicable towards wound healing. We primarily sought to confirm the mechanical properties and cell compatibility of these ZnO NP infused scaffolds. Methods: The antibacterial property of the ZnO NPs was confirmed by hydroxyl radical generation using ultraviolet (U.V.) photocatalysis. Titanium dioxide (TiO2), a well-known antibacterial compound, was used as a positive control (1% w/v) for the ZnO NP-based alginate constructs and their antibacterial efficacies compared. Among the ZnO group, 3D printed gels containing 0.5% and 1% w/v of ZnO were analyzed and compared with manually casted samples via SEM, swelling evaluation, and rheological analysis. Envisioning an in-vivo application for the 3D printed ZnO NP-based alginates, we studied their antibacterial properties by bacterial broth testing, cytocompatibility via live/dead assay, and moisture retention capabilities utilizing a humidity sensor. Results: 3D printed constructs revealed significantly greater pore sizes and enhanced structural stability compared to manually casted samples. For all samples, the addition of ZnO or TiO2 resulted in significantly stiffer gels in comparison with the alginate control. Bacterial resistance testing on Staphylococcus epidermidis indicated the addition of ZnO NPs to the gels decreased bacterial growth when compared to the alginate only gels. Cell viability of STO-fibroblasts was not adversely affected by the addition of ZnO NPs to the alginate gels. Furthermore, the addition of increasing doses of ZnO NPs to the alginate demonstrated increased humidity retention in gels. Discussion: The customization of 3D printed alginates containing antibacterial ZnO NPs leads to an alternative that allows accessible mobility of molecular exchange required for improving chronic wound healing. This scaffold can provide a cost-effective and durable antibacterial treatment option.


Assuntos
Alginatos/química , Alginatos/farmacologia , Hidrogéis/química , Nanopartículas/química , Cicatrização/efeitos dos fármacos , Óxido de Zinco/química , Sobrevivência Celular/efeitos dos fármacos , Fibroblastos/citologia
4.
Adv Exp Med Biol ; 1250: 49-61, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32601937

RESUMO

A wide variety of hydrogels have been proposed for tissue engineering applications, cell encapsulation, and bioinks for bioprinting applications. Cell-laden hydrogel constructs rely on natural hydrogels such as alginate, agarose, chitosan, collagen, gelatin, fibroin, and hyaluronic acid (HA), as well as on synthetic hydrogels such as poloxamers (Pluronics®) and polyethylene glycol (PEG). Alginate has become more and more important in the last years, thanks to the possibility to prepare alginate hydrogels suitable for cell encapsulation mainly because of the mild and reversible cross-linking conditions. In this paper alginate will be described in detail with respect to its chemistry, cross-linking behavior, biocompatibility, manufacturing capacity, and possible modifications.


Assuntos
Alginatos , Encapsulamento de Células , Hidrogéis , Engenharia Tecidual , Tecidos Suporte , Alginatos/química , Bioimpressão , Hidrogéis/química , Tecidos Suporte/química
5.
Ecotoxicol Environ Saf ; 203: 111002, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32684519

RESUMO

In this paper, environmental friendly magnetic composite adsorbent (MSAL), exhibited excellent adsorption capacity for lead ions in the solution, was successfully prepared using two non-biologically toxic materials including L-cysteine and sodium alginate. Batch experiments were carried out to discuss the influences of different parameters like pH, adsorbent dosing, initial concentration and contact time on adsorption performance. Results showed sorption process followed by pseudo-second-order kinetic model and Langmuir isotherm model, which suggested the adsorption was limited by the chemical process dominated by the molecular layer. Based on Langmuir isotherm model, the maximum Pb(Ⅱ) adsorption capacity was about 330 mg/g, which was better than a large amount of other lead adsorbents. Various analytical methods, such as SEM-EDS, FTIR, VSM, TGA, XPS and Zeta potential, were applied to characterize the performance of this adsorbent as well as exploring the adsorption mechanism. Characterization results found this adsorbent exhibited a large contact area, good thermal stability, sufficient adsorption sites and excellent magnetic responsiveness. It also has been found that the adsorption mechanism mainly included ion exchange and chelation between amino, carboxyl and lead ions. After 5 cycles, the adsorption capacity decreased from 98.04% to 87.40% and still maintained at high level. The average iron ions concentration in the adsorbed solution sample or in the regeneration solution were 0.34 mg/L and 0.15 mg/L. Overall, all above results imply that MSAL is a promising reusable adsorbent for removing Pb(Ⅱ) in solution.


Assuntos
Chumbo/análise , Nanopartículas de Magnetita/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Alginatos/química , Cisteína/química , Óxido Ferroso-Férrico/química , Concentração de Íons de Hidrogênio , Cinética , Fenômenos Magnéticos , Propriedades de Superfície
6.
Food Chem ; 333: 127483, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32679415

RESUMO

The aim of the present paper was to unravel the effect of a standardized in vitro European protocol of digestion-fermentation over Ca(II)-alginate beads synthesized with sugars and biopolymers. Special emphasis on the antioxidant capacity using methods that simulate physiological conditions, short-chain fatty acids (SCFAs) production, and a detailed study of the microstructure of the gel network by SAXS at several scales (1-100 nm) were considered. Beads released high antioxidant capacity during digestion assessed by several methods, comparable to some common foods; antioxidant capacity was improved with sucrose and arabic gum inclusion in the formulation. After fermentation by gut microbiota, a ten-fold increase in the antioxidant values and an important SCFAs production were obtained, revealing the enhanced ability to produce these functional biomolecules. The microstructural analysis of Ca(II)-alginate showed an advantageous behavior: they slightly changed in oral and gastric fluids and partially dissolved their structure in intestinal fluid, where absorption occurs.


Assuntos
Alginatos/metabolismo , Antioxidantes/metabolismo , Ácidos Graxos Voláteis/biossíntese , Fermentação , Goma Arábica/química , Microesferas , Sacarose/química , Alginatos/química , Biomimética , Microbioma Gastrointestinal
7.
PLoS One ; 15(7): e0236371, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32706802

RESUMO

We present a simple but accurate algorithm to calculate the flow and shear rate profile of shear thinning fluids, as typically used in biofabrication applications, with an arbitrary viscosity-shear rate relationship in a cylindrical nozzle. By interpolating the viscosity with a set of power-law functions, we obtain a mathematically exact piecewise solution to the incompressible Navier-Stokes equation. The algorithm is validated with known solutions for a simplified Carreau-Yasuda fluid, full numerical simulations for a realistic chitosan hydrogel as well as experimental velocity profiles of alginate and chitosan solutions in a microfluidic channel. We implement the algorithm in an easy-to-use Python tool, included as Supplementary Material, to calculate the velocity and shear rate profile during the printing process, depending on the shear thinning behavior of the bioink and printing parameters such as pressure and nozzle size. We confirm that the shear stress varies in an exactly linear fashion, starting from zero at the nozzle center to the maximum shear stress at the wall, independent of the shear thinning properties of the bioink. Finally, we demonstrate how our method can be inverted to obtain rheological bioink parameters in-situ directly before or even during printing from experimentally measured flow rate versus pressure data.


Assuntos
Alginatos/química , Quitosana/química , Hidrogéis/química , Agulhas , Impressão Tridimensional/instrumentação , Algoritmos , Hidrodinâmica , Microfluídica , Resistência ao Cisalhamento , Viscosidade
8.
PLoS One ; 15(6): e0234441, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32525941

RESUMO

Human iPSC-derived hepatocytes hold great promise as a cell source for cell therapy and drug screening. However, the culture method for highly-quantified hepatocytes has not yet been established. Herein, we have developed an encapsulation and 3D cultivation method for iPSC-hepatocytes in core-shell hydrogel microfibers (a.k.a. cell fiber). In the fiber-shaped 3D microenvironment consisting of abundant extracellular matrix (ECM), the iPSC-hepatocytes exhibited many hepatic characteristics, including the albumin secretion, and the expression of the hepatic marker genes (ALB, HNF4α, ASGPR1, CYP2C19, and CYP3A4). Furthermore, we found that the fibers were mechanically stable and can be applicable to hepatocyte transplantation. Three days after transplantation of the microfibers into the abdominal cavity of immunodeficient mice, human albumin was detected in the peripheral blood of the transplanted mice. These results indicate that the iPSC-hepatocyte fibers are promising either as in vitro models for drug screening or as implantation grafts to treat liver failure.


Assuntos
Técnicas de Cultura de Células/métodos , Encapsulamento de Células/métodos , Hepatócitos/fisiologia , Células-Tronco Pluripotentes Induzidas/fisiologia , Cavidade Abdominal/cirurgia , Alginatos/química , Animais , Técnicas de Cultura de Células/instrumentação , Diferenciação Celular , Encapsulamento de Células/instrumentação , Terapia Baseada em Transplante de Células e Tecidos/métodos , Perfilação da Expressão Gênica , Hepatócitos/transplante , Humanos , Hidrogéis/química , Falência Hepática/terapia , Masculino , Camundongos , Esferoides Celulares
9.
Food Chem ; 328: 127144, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-32474242

RESUMO

The combined effects of ultrasound (intensity of 15.6 W/cm2 and sonication for 5 min) with potassium alginate (PA) marination (UPA) on tenderizing old chicken breast meat, and possible mechanisms from tissue to protein, were investigated. UPA-treated meat exhibited the lowest moisture loss and shear force (optimized tenderness). The increased fiber space benefited PA invasion to form a heat-induced barrier for harder muscle contraction and avoid moisture withdrawal. Special scale-like structures of dried myofibrillar protein (MP) and the three-dimensional network induced by interactions between PA and MP increased the tenderness. UPA treatment induced stronger electrostatic repulsion between PA molecules and more ß-sheet structures of MP, accompanied by a smallest size. The more easily heat-denatured myosin and looser myofibrils accelerated the temperature rise. More immobilized water restricted to myofibrils and moisture captured in the gel network promoted water retention. UPA treatment could be a promising technology to tenderize old chicken breast meat.


Assuntos
Alginatos/química , Galinhas , Produtos Avícolas , Animais , Dicroísmo Circular , Culinária , Fibras na Dieta/análise , Indústria de Processamento de Alimentos/métodos , Miofibrilas/química , Miofibrilas/ultraestrutura , Miosinas/química , Proteínas de Aves Domésticas/química , Ultrassom , Água/análise
10.
Food Chem ; 330: 127195, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32585586

RESUMO

Efficient delivery of macular carotenoid lutein to target retinal tissue is possible with enhanced intestinal uptake remains a major challenge owing to the polarity, sensitivity to light, heat and solubility. In this study, to overcome such constraints, biodegradable polymers chitosan-sodium alginate-oleic acid based nano-carrier loaded with lutein (LNCs) was prepared and safety efficacy was examined in vivo. Acute-toxicity of LNCs (0.1, 1, 10 and 100 mg/kg body weight) revealed that the LD50 of LNCs was higher than 100 mg/kg body weight. In subacute-toxicity of LNCs (1 and 10 mg/kg body weight) revealed no mortality with no morphological and clinical changes in rats. Histology, haematology and biochemical analysis of urine and plasma confirmed no toxicity of LNCs compared to control. Post-prandial plasma and tissue (retina) levels of lutein from LNCs were higher. Results demonstrate increased bioavailability of lutein from LNCs with no toxicity suggests applications in food and pharma.


Assuntos
Alginatos/química , Quitosana/química , Luteína/metabolismo , Nanoestruturas , Ácido Oleico/química , Animais , Disponibilidade Biológica , Feminino , Luteína/química , Luteína/toxicidade , Ratos , Ratos Wistar , Solubilidade
11.
Chemosphere ; 258: 127148, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32535434

RESUMO

Tetrahydrofuran (THF) is a common highly toxic cyclic aliphatic ether that frequently exists in waste gases. Removal of gaseous THF is a serious issue with important environmental ramifications. A novel three-phase airlift bioreactor (TPAB) loaded with immobilized cells was developed for efficient THF removal from gas streams. An effective THF-degrading transformant, Pseudomonas oleovorans GDT4, which contains the pTn-Mod-OTc-gfp plasmid and was tagged with a green fluorescent protein (GFP), was constructed. Continuous treatment of THF-containing waste gases was succeeded by the GFP-labelled cells immobilized with calcium alginate and activated carbon fiber in the TPAB for 60 days with >90% removal efficiency. The number of fluorescent cells in the beads reached 1.7 × 1011 cells·g-1 of bead on day 10, accounting for 83.3% of the total number of cells. The amount further increased to 3.0 × 1011 cells·g-1 of bead on day 40. However, it decreased to 2.5 × 1011 cells·g-1 of bead with a substantial increase in biomass in the liquid because of cell leakage and hydraulic shock. PCR-DGGE revealed that P. oleovorans was the dominant microorganism throughout the entire operation. The maximum elimination capacity was affected by empty bed residence time (EBRT). The capacity was only 25.9 g m-3·h-1 at EBRT of 80 s, whereas it reached 37.8 g m-3·h-1 at EBRT of 140 s. This work provides an alternative method for full-scale removal of gaseous THF and presents a useful tool for determining the biomass of a specific degrader in immobilized beads.


Assuntos
Reatores Biológicos/microbiologia , Furanos/metabolismo , Pseudomonas oleovorans/metabolismo , Gerenciamento de Resíduos/métodos , Alginatos/química , Biodegradação Ambiental , Biomassa , Fibra de Carbono , Células Imobilizadas/metabolismo , Carvão Vegetal , Desenho de Equipamento , Gases , Proteínas de Fluorescência Verde/genética , Microbiota , Microrganismos Geneticamente Modificados , Pseudomonas oleovorans/citologia , Pseudomonas oleovorans/genética , Gerenciamento de Resíduos/instrumentação
12.
Food Chem ; 327: 126920, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32434125

RESUMO

The influence of the timing of inoculation (sequential and simultaneous alcoholic fermentation (AF)/malolactic fermentation (MLF)) on the chemical and sensory properties of red wines was studied. The impact of the encapsulation of Oenococcus oeni into SiO2-alginate hydrogel (Si-ALG) and the addition of lysozyme in wines inoculated with encapsulated bacteria were also analysed. There was a significant influence of the timing of inoculation on the volatile composition of the wines just as on the amino acid and biogenic amine content. The wines produced by simultaneous AF/MLF showed the highest contents of some volatile compounds, such as ethyl esters and terpenes, as well as amino acids and tyramine. Bacterial encapsulation affected the volatile and amino acid profile of the wines, while the biogenic amine composition was not modified. The chemical composition of the wines was not altered by the presence of lysozyme. A trained panel did not perceive substantial differences between treatments.


Assuntos
Aminoácidos/metabolismo , Aminas Biogênicas/metabolismo , Muramidase/metabolismo , Saccharomyces cerevisiae/metabolismo , Dióxido de Silício/química , Vinho/análise , Alginatos/química , Cor , Fermentação , Oenococcus/metabolismo
13.
Chemosphere ; 256: 127124, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32450354

RESUMO

In the present work, talc (a low-cost clay) encapsulated salts alginate (TAL) beads were synthesized by cross-linking with lanthanum ion and tested for phosphate adsorption. Multiple methods were applied for the characterization of composites. The combined effect of talc and lanthanum improved phosphate removal performance of TAL beads. Factors such as talc content, La3+ concentration, adsorbent dosage, pH, co-existing ions (Cl-, NO3- and SO42-) were studied in batch experiments. The optimized TAL-7 beads exhibited satisfactory selectivity towards phosphate in the coexistence of competing anions and could remain efficient phosphate removal in the pH range of 4-6. The phosphate removal efficiency reached to 95% with a maximum uptake of 16.4 mg P/g obtained at the optimal pH 4. Further experiments suggested that Langmuir isotherm model and the pseudo-second-order kinetic model could well describe the phosphate adsorption process of TAL-7 beads. Moreover, TAL-7 beads exhibited superior phosphate fixation performance in the long-term experiment. The results from adsorption experiment and characterization analysis demonstrated that TAL-7 beads could be a cost-effective and promising biosorbent for phosphate adsorption and fixation in the aqueous environment.


Assuntos
Alginatos/química , Hidrogéis/química , Lantânio/química , Fosfatos/análise , Talco/química , Poluentes Químicos da Água/análise , Adsorção , Ânions , Concentração de Íons de Hidrogênio , Íons/química , Cinética , Fosfatos/química , Água/química , Poluentes Químicos da Água/química , Purificação da Água/métodos
14.
Soft Matter ; 16(21): 5044-5053, 2020 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-32452496

RESUMO

Conventional approaches to mitigate fouling of membrane surfaces impart hydrophilicity to the membrane surface, which increases the water of hydration and fluidity near the surface. By contrast, we demonstrate here that tuning the membrane surface energy close to that of the dispersive component of water surface tension (21.8 mN m-1) can also improve the antifouling properties of the membrane. Specifically, ultrafiltration (UF) membranes were first modified using polydopamine (PDA) followed by grafting of amine-terminated polysiloxane (PSi-NH2). For example, with 2 g L-1 PSi-NH2 coating solution, the obtained coating layer contains 53% by mass fraction PSi-NH2 and exhibits a total surface energy of 21 mN m-1, decreasing the adsorption of bovine serum albumin by 44% compared to the unmodified membrane. When challenged with 1 g L-1 sodium alginate in a constant-flux crossflow system, the PSi-NH2-grafted membrane exhibits a 70% lower fouling rate than the pristine membrane at a water flux of 110 L (m2 h)-1 and good stability when cleaned with NaOH solutions.


Assuntos
Incrustação Biológica/prevenção & controle , Membranas Artificiais , Siloxanas/química , Absorção Fisico-Química , Alginatos/química , Indóis/química , Polímeros/química , Soroalbumina Bovina/química , Ultrafiltração/métodos , Purificação da Água/métodos
15.
PLoS One ; 15(4): e0231893, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32298378

RESUMO

BACKGROUND/OBJECTIVES: Vaccination is the most important tool for controlling brucellosis, but currently there is no vaccine available for canine brucellosis, which is a zoonotic disease of worldwide distribution caused by Brucella canis. This study aimed to evaluate protection and immune response induced by Brucella ovis ΔabcBA (BoΔabcBA) encapsulated with alginate against the challenge with Brucella canis in mice and to assess the safety of this strain for dogs. METHODS: Intracellular growth of the vaccine strain BoΔabcBA was assessed in canine and ovine macrophages. Protection induced by BoΔabcBA against virulent Brucella canis was evaluated in the mouse model. Safety of the vaccine strain BoΔabcBA was assessed in experimentally inoculated dogs. RESULTS: Wild type B. ovis and B. canis had similar internalization and intracellular multiplication profiles in both canine and ovine macrophages. The BoΔabcBA strain had an attenuated phenotype in both canine and ovine macrophages. Immunization of BALB/c mice with alginate-encapsulated BoΔabcBA (108 CFU) induced lymphocyte proliferation, production of IL-10 and IFN-γ, and protected against experimental challenge with B. canis. Dogs immunized with alginate-encapsulated BoΔabcBA (109 CFU) seroconverted, and had no hematologic, biochemical or clinical changes. Furthermore, BoΔabcBA was not detected by isolation or PCR performed using blood, semen, urine samples or vaginal swabs at any time point over the course of this study. BoΔabcBA was isolated from lymph nodes near to the site of inoculation in two dogs at 22 weeks post immunization. CONCLUSION: Encapsulated BoΔabcBA protected mice against experimental B. canis infection, and it is safe for dogs. Therefore, B. ovis ΔabcBA has potential as a vaccine candidate for canine brucellosis prevention.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Vacina contra Brucelose/imunologia , Brucella ovis/genética , Brucelose/prevenção & controle , Doenças do Cão/prevenção & controle , Alginatos/química , Animais , Formação de Anticorpos , Brucella canis/patogenicidade , Brucella ovis/imunologia , Brucella ovis/isolamento & purificação , Brucelose/microbiologia , Brucelose/patologia , Doenças do Cão/microbiologia , Doenças do Cão/patologia , Cães , Feminino , Imunização , Fígado/microbiologia , Fígado/fisiologia , Linfócitos/citologia , Linfócitos/imunologia , Linfócitos/metabolismo , Macrófagos/citologia , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mutação , Ovinos
16.
Food Chem ; 322: 126638, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32283365

RESUMO

This study investigated the effects of adding different polysaccharides (Arabic Gum (GA), Sodium Alginate (SA) and Soy-soluble polysaccharides (SSPS)) on the embedding properties and physical stability of soybean protein isolate (SPI). 1-Octacosanol (1-Octa) was encapsulated in SPI nanoparticles. The addition of GA, SA, SSPS not only increased the encapsulation efficiency of 1-Octa from 90.38% to 96.65%, 95.49%, 94.74%, respectively, but also increased the ζ-potential of nanoparticles from -29.05 mV to -38.77 mV, -41.50 mV, -38.00 mV, respectively. Through the changes of ζ-potential and the Fourier transform infrared spectroscopy (FT-IR), it can be known that anionic polysaccharides can also combine with positive charges of SPI by the electrostatic interaction under neutral conditions. The thermal stability of nanoparticles has been greatly improved, and SA has the best effect on denaturation temperature of nanoparticles in aqueous phase. Overall, The nanoparticles of SPI, 1-Octa and polysaccharides have the potential to be used in drinks.


Assuntos
Álcoois Graxos/química , Aditivos Alimentares/química , Polissacarídeos/química , Proteínas de Soja/química , Soja/química , Alginatos/química , Temperatura Alta , Nanopartículas/química , Estabilidade Proteica , Espectroscopia de Infravermelho com Transformada de Fourier
17.
Niger J Clin Pract ; 23(3): 284-290, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32134024

RESUMO

Aims: The aim of this study was to determine the best approach to reduce the unfavorable change in the three different dimensions of impressions using disinfection durations of 15 and 30 min; three different disinfection procedures; and alginate impression products as research factors. Materials and Methods: CA37, impressional, and cream alginate impressions were used; distortion in the AB, AC, and BC dimensions of impressions using disinfection durations of 15 and 30 min was studied; and no disinfection (ND), conventional disinfection (CD), and sonicator-activated disinfection (SAD) procedures were measured. Results: Regarding AB dimension, the impressional has best performance when CD was applied for both 15 and 30 min. When SAD was applied for 15 min, impressional and cream alginates provide best performance. When CD was applied for 15 min, CA37 and impressional alginates provide best performance. Although ND-applied CA37 alginate after 30 min provides best performance, because of many outlier values, its implication may not be considered as meaningful. Regarding AC dimension, cream alginate has best performance when CD was applied for 15 min. The AC distances in all the alginates are considerably different from the base model after 30 min. Regarding BC dimension, only the CA37 alginate has the best performance when ND was applied for 15 min. All the alginates are considerably different from that of the base model after 30 min. Conclusion: Preference of 15-min disinfection can provide favorable results to obtain all impressions with minimally distorted dimensions. CD is an adequate procedure. The studied SAD needs to be developed further. All alginates are comparably successful to obtain impressions with desired distortion degrees.


Assuntos
Alginatos/química , Desinfetantes de Equipamento Odontológico/administração & dosagem , Desinfetantes de Equipamento Odontológico/química , Materiais para Moldagem Odontológica/química , Desinfecção/métodos , Esterilização/métodos , Técnica de Moldagem Odontológica , Modelos Dentários , Humanos , Controle de Infecções Dentárias/métodos , Teste de Materiais/métodos , Fatores de Tempo
18.
Chemosphere ; 251: 126074, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32163776

RESUMO

The adsorption method is generally considered a promising technique to remove inorganic and organic contaminants in an economically and environmentally friendly superior manner. In this study, organic montmorillonite sodium alginate composites were prepared, in which, montmorillonite and cationic surfactant (cetyltrimethylammonium bromide, CTAB) in different added amounts were coagulated with sodium alginate using CaCl2 as the crosslinking agent. The morphological properties of the composites were characterized thoroughly and employed in three typical target pollutants of polycyclic aromatic hydrocarbons (PAHs) (acenaphthene, fluorene, and phenanthrene) by batch adsorption experiments from aqueous solution. The composites provide an efficient alternative for PAHs removals. The composites could be stably separated and regenerated with methyl alcohol. Furthermore, the adsorption kinetic and isotherm data were well described by the Elovich kinetic and the Freundlich isotherm model, respectively. According to these, the adsorption process occurred via multilayer adsorption on the composite's energetically heterogeneous surface. Moreover, pore diffusion and hydrophobicity played a dominant role in the adsorption mechanism. Overall, our study offers a developed adsorbent that has the advantage of being recyclable, low cost, biodegradable and biocompatible for effectively removing PAHs from aqueous solution.


Assuntos
Alginatos/química , Bentonita/química , Hidrocarbonetos Policíclicos Aromáticos/química , Poluentes Químicos da Água/química , Adsorção , Difusão , Interações Hidrofóbicas e Hidrofílicas , Cinética , Nanocompostos , Hidrocarbonetos Policíclicos Aromáticos/análise , Tensoativos , Água , Poluentes Químicos da Água/análise
19.
Int J Nanomedicine ; 15: 333-346, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32021183

RESUMO

Purpose: Wound healing, especially of extensive full-thickness wounds, is one of the most difficult problems in clinical studies. In this study, we prepared a novel substance P (SP)-delivery system using zeolite imidazolate framework-8 (ZIF-8) nanoparticles. Methods: We synthesized ZIF-8 nanoparticles using a modified biomimetic mineralization method. We then coated SP-loaded ZIF-8 nanoparticles (SP@ZIF-8) with polyethylene glycol-thioketal (PEG-TK) to fabricate SP@ZIF-8-PEG-TK nanoparticles, and encapsulated them in injectable hydrogel composed of sodium alginate and pectin and cross-linked using calcium chloride. The final hydrogel wound dressing containing SP@ZIF-8-PEG-TK nanoparticles was called SP@ZIF-8-PEG-TK@CA. Results: The fabricated ZIF-8 nanoparticles had high SP-loading efficiency. SP-release assay showed that the SP@ZIF-8-PEG-TK nanoparticles maintained drug activity and showed responsive release under stimulation by reactive oxygen species. The SP@ZIF-8-PEG-TK nanoparticles promoted proliferation of human dermal fibroblasts, up-regulated expression levels of inflammation-related genes in macrophages, and exhibited favorable cytocompatibility in vitro. Full-thickness excision wound models in vivo confirmed that SP@ZIF-8-PEG-TK@CA dressings had excellent wound-healing efficacy by promoting an early inflammatory response and subsequent M2 macrophage polarization in the wound-healing process. Conclusion: In conclusion, these findings indicated that SP@ZIF-8-PEG-TK@CA dressings might be useful for wound dressing applications in the clinic.


Assuntos
Bandagens , Nanopartículas/química , Espécies Reativas de Oxigênio/metabolismo , Substância P/administração & dosagem , Cicatrização/efeitos dos fármacos , Zeolitas/química , Alginatos/química , Animais , Cloreto de Cálcio/química , Proliferação de Células/efeitos dos fármacos , Reagentes para Ligações Cruzadas/química , Sistemas de Liberação de Medicamentos/métodos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Hidrogéis/química , Imidazóis/química , Camundongos Endogâmicos BALB C , Nanopartículas/administração & dosagem , Pectinas/química , Polietilenoglicóis/química , Substância P/farmacocinética
20.
J Photochem Photobiol B ; 204: 111767, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32006893

RESUMO

Colon carcinoma is a recurring type of cancer that affects the intestine epithelial with a poor survival rate. It was already proven the anticancer property of hesperidin in various cancers but the bioavailability hesperidin is poor, which hinders the hesperidin usage. In this investigation we synthesized hesperidin loaded Zn2+@ SA/PCT nanocomposites and assessed its anticancer potential against colon cancer (HCT116) cells. Hesperidin loaded Zn2+@ SA/PCT nanocomposites were characterized using Fourier transform infrared (FTIR), X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM) analysis. The drug releasing capacity and cytotoxic property was assessed via drug releasing assay, MTT assay with HCT116 cells. The anticancer potency of hesperidin nanocomposites were evaluated with TUNEL, DAPI staining, reactive oxygen species (ROS) generation assay and it is confirmed with flow cytometry analysis of MMP disruption in colon cancer (HCT116) cell line. Further the immunoblotting analysis of cysteine proteases Caspases 3, 9, PARP, proapoptotic protein Bax and antiapoptotic protein Bcl2 were performed. The results of FTIR, XRD and electroscopic analyses confirmed the synthesized hesperidin nanocomposites accomplish the properties of potent nanodrug and the MTT assay authentically confirmed that the synthesized hesperidin nanocomposite inhibited the HCT116 cell growth, and the results of fluorescent staining proved that the hesperidin nanocomposite induced the apoptotic mediated cell necrosis via promoting the expression of apoptotic proteins thereby induced the apoptosis in colon cancer (HCT116) cells. Hence, it was concluded that the, hesperidin loaded nanocomposites persuasively inhibited proliferation of colon carcinoma cell and induced apoptosis in in vitro condition.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Hesperidina/química , Nanocompostos/química , Alginatos/química , Antineoplásicos Fitogênicos/química , Caspase 3/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Composição de Medicamentos , Liberação Controlada de Fármacos , Células HCT116 , Hesperidina/farmacologia , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Pectinas/química , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Zinco/química
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