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1.
Int J Immunopathol Pharmacol ; 38: 3946320241249429, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38721971

RESUMO

OBJECTIVE: This study investigated the raft-forming suspension of famotidine as an anti-reflux formulation to improve the oral bioavailability of narrow absorption window drugs by enhancing gastric residence time (GRT) and preventing gastro-esophageal reflux disease (GERD). METHOD: Various combinations of raft-forming agents, such as Tragacanth gum (TG), guar gum (GG), and xanthan gum (XG), were evaluated alongside sodium alginate (SA) to develop an effective raft. Preformulation studies and preliminary screening were conducted to identify the most suitable raft-forming agent, and GG was chosen due to its mucilaginous properties. The formulation was optimized using a 32 full factorial design, with the quantities of GG and SA as independent factors and apparent viscosity and in-vitro drug release (%) as dependent factors. The in vivo floating behavior study was performed for optimized and stabilized formulation. RESULTS: Among the tested batches, F6 was selected as the optimized formulation. It exhibited desirable characteristics such as adequate raft weight for extended floating in gastric fluid, improved apparent viscosity, and a significant percentage of drug release at 12 h. A mathematical model was applied to the in-vitro data to gain insights into the drug release mechanism of the formulation. The stability of the suspension was assessed under accelerated conditions, and it demonstrated satisfactory stability. The formulation remains floating in the Rabbit stomach for more than 12 h. CONCLUSION: It concludes that the developed formulation has enhanced bioavailability in the combination of GG and SA. The floating layer of the raft prevents acid reflux, and the famotidine is retained for an extended period of time in the gastric region, preventing excess acid secretion. The developed formulations are effective for stomach ulcers and GERD, with the effect of reducing acid secretion by H2 receptor antagonists.


Assuntos
Sistemas de Liberação de Medicamentos , Famotidina , Galactanos , Famotidina/administração & dosagem , Famotidina/farmacocinética , Animais , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Alginatos , Refluxo Gastroesofágico/tratamento farmacológico , Refluxo Gastroesofágico/metabolismo , Disponibilidade Biológica , Mananas/administração & dosagem , Gomas Vegetais , Viscosidade , Masculino , Coelhos , Mucosa Gástrica/metabolismo , Mucosa Gástrica/efeitos dos fármacos , Polissacarídeos Bacterianos , Estabilidade de Medicamentos , Administração Oral
2.
Nano Lett ; 24(19): 5894-5903, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38709593

RESUMO

The combination of radiotherapy (RT) and immunotherapy shows promise in improving the clinical treatment of solid tumors; however, it faces challenges of low response rates and systemic toxicity. Herein, an implantable alginate/collagen hydrogel encapsulating C-C motif ligand 21 (CCL21)-expressing dendritic cells (CCL21-DCs@gel) was developed to potentiate the systemic antitumor effects of RT. The hydrogel functioned as a suitable reservoir for in vivo culture and proliferation of CCL21-DCs, thereby enabling sustained CCL21 release. The local CCL21 gradient induced by CCL21-DCs@gel significantly enhanced the efficacy of RT in suppressing primary tumor growth and inhibiting distant metastasis across several mouse models. Furthermore, the combination of RT with CCL21-DCs@gel provided complete prophylactic protection to mice. Mechanistic investigations revealed that CCL21-DCs@gel potentiated RT by promoting tumor lymphangiogenesis and attracting immune cell infiltration into the tumor. Collectively, these results suggest that CCL21-DCs@gel is a promising adjunct to RT for effectively eradicating tumors and preventing tumor recurrence.


Assuntos
Quimiocina CCL21 , Células Dendríticas , Hidrogéis , Animais , Hidrogéis/química , Camundongos , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Linhagem Celular Tumoral , Humanos , Alginatos/química , Neoplasias/radioterapia , Neoplasias/patologia , Neoplasias/imunologia , Colágeno/química , Imunoterapia/métodos
3.
J Nanobiotechnology ; 22(1): 241, 2024 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-38735933

RESUMO

BACKGROUND: Colorectal cancer (CRC) incidence is increasing in recent years due to intestinal flora imbalance, making oral probiotics a hotspot for research. However, numerous studies related to intestinal flora regulation ignore its internal mechanisms without in-depth research. RESULTS: Here, we developed a probiotic microgel delivery system (L.r@(SA-CS)2) through the layer-by-layer encapsulation technology of alginate (SA) and chitosan (CS) to improve gut microbiota dysbiosis and enhance anti-tumor therapeutic effect. Short chain fatty acids (SCFAs) produced by L.r have direct anti-tumor effects. Additionally, it reduces harmful bacteria such as Proteobacteria and Fusobacteriota, and through bacteria mutualophy increases beneficial bacteria such as Bacteroidota and Firmicutes which produce butyric acid. By binding to the G protein-coupled receptor 109A (GPR109A) on the surface of colonic epithelial cells, butyric acid can induce apoptosis in abnormal cells. Due to the low expression of GPR109A in colon cancer cells, MK-6892 (MK) can be used to stimulate GPR109A. With increased production of butyrate, activated GPR109A is able to bind more butyrate, which further promotes apoptosis of cancer cells and triggers an antitumor response. CONCLUSION: It appears that the oral administration of L.r@(SA-CS)2 microgels may provide a treatment option for CRC by modifying the gut microbiota.


Assuntos
Ácidos Graxos Voláteis , Microbioma Gastrointestinal , Limosilactobacillus reuteri , Probióticos , Microbioma Gastrointestinal/efeitos dos fármacos , Probióticos/farmacologia , Humanos , Ácidos Graxos Voláteis/metabolismo , Animais , Limosilactobacillus reuteri/metabolismo , Camundongos , Quitosana/química , Alginatos/química , Alginatos/farmacologia , Apoptose/efeitos dos fármacos , Antineoplásicos/farmacologia , Antineoplásicos/química , Administração Oral , Neoplasias Colorretais/tratamento farmacológico , Linhagem Celular Tumoral , Receptores Acoplados a Proteínas G/metabolismo , Microgéis/química , Camundongos Endogâmicos BALB C , Ácido Butírico/farmacologia , Ácido Butírico/metabolismo
4.
Sci Rep ; 14(1): 10931, 2024 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740842

RESUMO

Biomaterial scaffolds play a pivotal role in the advancement of cultured meat technology, facilitating essential processes like cell attachment, growth, specialization, and alignment. Currently, there exists limited knowledge concerning the creation of consumable scaffolds tailored for cultured meat applications. This investigation aimed to produce edible scaffolds featuring both smooth and patterned surfaces, utilizing biomaterials such as salmon gelatin, alginate, agarose and glycerol, pertinent to cultured meat and adhering to food safety protocols. The primary objective of this research was to uncover variations in transcriptomes profiles between flat and microstructured edible scaffolds fabricated from marine-derived biopolymers, leveraging high-throughput sequencing techniques. Expression analysis revealed noteworthy disparities in transcriptome profiles when comparing the flat and microstructured scaffold configurations against a control condition. Employing gene functional enrichment analysis for the microstructured versus flat scaffold conditions yielded substantial enrichment ratios, highlighting pertinent gene modules linked to the development of skeletal muscle. Notable functional aspects included filament sliding, muscle contraction, and the organization of sarcomeres. By shedding light on these intricate processes, this study offers insights into the fundamental mechanisms underpinning the generation of muscle-specific cultured meat.


Assuntos
Diferenciação Celular , Carne , Alicerces Teciduais , Transcriptoma , Alicerces Teciduais/química , Animais , Biopolímeros , Desenvolvimento Muscular/genética , Alginatos/química , Perfilação da Expressão Gênica , Sefarose/química , Materiais Biocompatíveis/química , Gelatina/química , Células Musculares/metabolismo , Salmão , Carne in vitro
5.
Int J Nanomedicine ; 19: 3861-3890, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38708178

RESUMO

Introduction: Cystic fibrosis (CF) is associated with pulmonary Pseudomonas aeruginosa infections persistent to antibiotics. Methods: To eradicate pseudomonal biofilms, solid lipid nanoparticles (SLNs) loaded with quorum-sensing-inhibitor (QSI, disrupting bacterial crosstalk), coated with chitosan (CS, improving internalization) and immobilized with alginate lyase (AL, destroying alginate biofilms) were developed. Results: SLNs (140-205 nm) showed prolonged release of QSI with no sign of acute toxicity to A549 and Calu-3 cells. The CS coating improved uptake, whereas immobilized-AL ensured >1.5-fold higher uptake and doubled SLN diffusion across the artificial biofilm sputum model. Respirable microparticles comprising SLNs in carbohydrate matrix elicited aerodynamic diameters MMAD (3.54, 2.48 µm) and fine-particle-fraction FPF (65, 48%) for anionic and cationic SLNs, respectively. The antimicrobial and/or antibiofilm activity of SLNs was explored in Pseudomonas aeruginosa reference mucoid/nonmucoid strains as well as clinical isolates. The full growth inhibition of planktonic bacteria was dependent on SLN type, concentration, growth medium, and strain. OD measurements and live/dead staining proved that anionic SLNs efficiently ceased biofilm formation and eradicated established biofilms, whereas cationic SLNs unexpectedly promoted biofilm progression. AL immobilization increased biofilm vulnerability; instead, CS coating increased biofilm formation confirmed by 3D-time lapse confocal imaging. Incubation of SLNs with mature biofilms of P. aeruginosa isolates increased biofilm density by an average of 1.5-fold. CLSM further confirmed the binding and uptake of the labeled SLNs in P. aeruginosa biofilms. Considerable uptake of CS-coated SLNs in non-mucoid strains could be observed presumably due to interaction of chitosan with LPS glycolipids in the outer cell membrane of P. aeruginosa. Conclusion: The biofilm-destructive potential of QSI/SLNs/AL inhalation is promising for site-specific biofilm-targeted interventional CF therapy. Nevertheless, the intrinsic/extrinsic fundamentals of nanocarrier-biofilm interactions require further investigation.


Assuntos
Antibacterianos , Biofilmes , Quitosana , Lipossomos , Nanopartículas , Infecções por Pseudomonas , Pseudomonas aeruginosa , Biofilmes/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/fisiologia , Humanos , Infecções por Pseudomonas/tratamento farmacológico , Nanopartículas/química , Quitosana/química , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/farmacocinética , Portadores de Fármacos/química , Fibrose Cística/tratamento farmacológico , Fibrose Cística/microbiologia , Lipídeos/química , Lipídeos/farmacologia , Percepção de Quorum/efeitos dos fármacos , Células A549 , Alginatos/química
6.
Carbohydr Polym ; 337: 122144, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38710569

RESUMO

In vivo, cells interact with the extracellular matrix (ECM), which provides a multitude of biophysical and biochemical signals that modulate cellular behavior. Inspired by this, we explored a new methodology to develop a more physiomimetic polysaccharide-based matrix for 3D cell culture. Maleimide-modified alginate (AlgM) derivatives were successfully synthesized using DMTMM to activate carboxylic groups. Thiol-terminated cell-adhesion peptides were tethered to the hydrogel network to promote integrin binding. Rapid and efficient in situ hydrogel formation was promoted by thiol-Michael addition "click" chemistry via maleimide reaction with thiol-flanked protease-sensitive peptides. Alginate derivatives were further ionically crosslinked by divalent ions present in the medium, which led to greater stability and allowed longer cell culture periods. By tailoring alginate's biofunctionality we improved cell-cell and cell-matrix interactions, providing an ECM-like 3D microenvironment. We were able to systematically and independently vary biochemical and biophysical parameters to elicit specific cell responses, creating custom-made 3D matrices. DMTMM-mediated maleimide incorporation is a promising approach to synthesizing AlgM derivatives that can be leveraged to produce ECM-like matrices for a broad range of applications, from in vitro tissue modeling to tissue regeneration.


Assuntos
Alginatos , Química Click , Matriz Extracelular , Hidrogéis , Maleimidas , Compostos de Sulfidrila , Maleimidas/química , Alginatos/química , Compostos de Sulfidrila/química , Hidrogéis/química , Hidrogéis/síntese química , Matriz Extracelular/metabolismo , Matriz Extracelular/química , Humanos , Reagentes de Ligações Cruzadas/química , Adesão Celular/efeitos dos fármacos , Animais
7.
Jt Dis Relat Surg ; 35(2): 361-367, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38727116

RESUMO

OBJECTIVES: This study aims to compare the radiological, biomechanical, and histopathological results of microfracture treatment and osteochondral damage repair treatment with a new scaffold product produced by the three-dimensional (3D) bioprinting method containing gelatin-hyaluronic acid-alginate in rabbits with osteochondral damage. MATERIALS AND METHODS: A new 3D bioprinted scaffold consisting of gelatin, hyaluronic acid, and alginate designed by us was implanted into the osteochondral defect created in the femoral trochlea of 10 rabbits. By randomization, it was determined which side of 10 rabbits would be repaired with a 3D bioprinted scaffold, and microfracture treatment was applied to the other knees of the rabbits. After six months of follow-up, the rabbits were sacrificed. The results of both treatment groups were compared radiologically, biomechanically, and histopathologically. RESULTS: None of the rabbits experienced any complications. The magnetic resonance imaging evaluation showed that all osteochondral defect areas were integrated with healthy cartilage in both groups. There was no significant difference between the groups in the biomechanical load test (p=0.579). No statistically significant difference was detected in the histological examination using the modified Wakitani scores (p=0.731). CONCLUSION: Our study results showed that 3D bioprinted scaffolds exhibited comparable radiological, biomechanical, and histological properties to the conventional microfracture technique for osteochondral defect treatment.


Assuntos
Alginatos , Bioimpressão , Cartilagem Articular , Gelatina , Ácido Hialurônico , Articulação do Joelho , Impressão Tridimensional , Alicerces Teciduais , Animais , Coelhos , Alginatos/química , Gelatina/química , Ácido Hialurônico/química , Ácido Hialurônico/uso terapêutico , Alicerces Teciduais/química , Cartilagem Articular/patologia , Cartilagem Articular/lesões , Cartilagem Articular/cirurgia , Articulação do Joelho/cirurgia , Articulação do Joelho/patologia , Bioimpressão/métodos , Modelos Animais de Doenças , Fenômenos Biomecânicos , Imageamento por Ressonância Magnética , Artroplastia Subcondral/métodos
8.
Sci Rep ; 14(1): 9972, 2024 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-38693342

RESUMO

This study presents a novel biosorbent developed by immobilizing dead Sp2b bacterial biomass into calcium alginate (CASp2b) to efficiently remove arsenic (AsIII) from contaminated water. The bacterium Sp2b was isolated from arsenic-contaminated industrial soil of Punjab, a state in India. The strain was designated Acinetobacter sp. strain Sp2b as per the 16S rDNA sequencing, GenBank accession number -OP010048.The CASp2b was used for the biosorption studies after an initial screening for the biosorption capacity of Sp2b biomass with immobilized biomass in both live and dead states. The optimum biosorption conditions were examined in batch experimentations with contact time, pH, biomass, temperature, and AsIII concentration variables. The maximum biosorption capacity (qmax = 20.1 ± 0.76 mg/g of CA Sp2b) was obtained at pH9, 35 ̊ C, 20 min contact time, and 120 rpm agitation speed. The isotherm, kinetic and thermodynamic modeling of the experimental data favored Freundlich isotherm (R2 = 0.941) and pseudo-2nd-order kinetics (R2 = 0.968) with endothermic nature (ΔH° = 27.42) and high randomness (ΔS° = 58.1).The scanning electron microscopy with energy dispersive X-ray (SEM-EDX) analysis indicated the As surface binding. The reusability study revealed the reasonable usage of beads up to 5 cycles. In conclusion, CASp2b is a promising, efficient, eco-friendly biosorbent for AsIII removal from contaminated water.


Assuntos
Acinetobacter , Alginatos , Arsênio , Biodegradação Ambiental , Biomassa , Poluentes Químicos da Água , Alginatos/química , Alginatos/metabolismo , Acinetobacter/metabolismo , Acinetobacter/genética , Arsênio/metabolismo , Poluentes Químicos da Água/metabolismo , Adsorção , Cinética , Concentração de Íons de Hidrogênio , Purificação da Água/métodos , Temperatura , Termodinâmica
9.
Environ Sci Technol ; 58(19): 8501-8509, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38696244

RESUMO

Iron/chromium hydroxide coprecipitation controls the fate and transport of toxic chromium (Cr) in many natural and engineered systems. Organic coatings on soil and engineered surfaces are ubiquitous; however, mechanistic controls of these organic coatings over Fe/Cr hydroxide coprecipitation are poorly understood. Here, Fe/Cr hydroxide coprecipitation was conducted on model organic coatings of humic acid (HA), sodium alginate (SA), and bovine serum albumin (BSA). The organics bonded with SiO2 through ligand exchange with carboxyl (-COOH), and the adsorbed amounts and pKa values of -COOH controlled surface charges of coatings. The adsorbed organic films also had different complexation capacities with Fe/Cr ions and Fe/Cr hydroxide particles, resulting in significant differences in both the amount (on HA > SA(-COOH) ≫ BSA(-NH2)) and composition (Cr/Fe molar ratio: on BSA(-NH2) ≫ HA > SA(-COOH)) of heterogeneous precipitates. Negatively charged -COOH attracted more Fe ions and oligomers of hydrolyzed Fe/Cr species and subsequently promoted heterogeneous precipitation of Fe/Cr hydroxide nanoparticles. Organic coatings containing -NH2 were positively charged at acidic pH because of the high pKa value of the functional group, limiting cation adsorption and formation of coprecipitates. Meanwhile, the higher local pH near the -NH2 coatings promoted the formation of Cr(OH)3. This study advances fundamental understanding of heterogeneous Fe/Cr hydroxide coprecipitation on organics, which is essential for successful Cr remediation and removal in both natural and engineered settings, as well as the synthesis of Cr-doped iron (oxy)hydroxides for material applications.


Assuntos
Cromo , Hidróxidos , Ferro , Hidróxidos/química , Ferro/química , Cromo/química , Soroalbumina Bovina/química , Adsorção , Substâncias Húmicas , Água/química , Precipitação Química , Alginatos/química
10.
Molecules ; 29(9)2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38731511

RESUMO

Alginate films plasticized with glycerol and enriched in raspberry and/or black currant seed oils were prepared via casting solution techniques. The intention was to create active films for food packaging where antioxidants in a film would deactivate oxidants in a packed product or its surroundings, improving conditions inside packaging and extending the shelf life of such a product. The prepared materials were characterized by physicochemical, spectroscopic, mechanical, water vapor transmission (WVTR), and antioxidant activity analysis. Infrared spectra of the alginate films with oils were similar to those without the additive; the band with a maximum at about 1740 cm-1 stood out. The prepared materials with oils were thicker, contained less water, were more yellow, and were less permeable to water vapor. Moreover, the presence of the oil in the films resulted in a slightly lower Young's modulus and lower stress at break values but higher strain at break. The antioxidant capacity of raspberry seed oil itself was about five times higher than that of black currant seed oil, and a similar trend was noticed for films modified with these oils. The results indicated that both oils could be used as active substances with antioxidant properties in food packaging.


Assuntos
Alginatos , Antioxidantes , Embalagem de Alimentos , Óleos de Plantas , Ribes , Rubus , Sementes , Embalagem de Alimentos/métodos , Alginatos/química , Antioxidantes/química , Antioxidantes/farmacologia , Óleos de Plantas/química , Sementes/química , Rubus/química , Ribes/química , Vapor
11.
ACS Biomater Sci Eng ; 10(5): 3188-3202, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38592024

RESUMO

Chronic wound repair is a clinical treatment challenge. The development of multifunctional hydrogels is of great significance in the key aspects of treating chronic wounds, including reducing oxidative stress, promoting angiogenesis, and improving the natural remodeling of extracellular matrix and immune regulation. In this study, we prepared a composite hydrogel, sodium alginate (SA)@MnO2/recombinant humanized collagen III (RHC)/mesenchymal stem cells (MSCs), composed of SA, MnO2 nanoparticles, RHC, and MSCs. The hydrogel has high mechanical properties and good biocompatibility. In vitro, SA@MnO2/RHC/MSCs hydrogel effectively enhanced the formation of intricate tubular structures and angiogenesis and showed synergistic effects on cell proliferation and migration. In vivo, the SA@MnO2/RHC/MSCs hydrogel enhanced diabetes wound healing, rapid re-epithelization, favorable collagen deposition, and abundant wound angiogenesis. These findings demonstrated that the combined effects of SA, MnO2, RHC, and MSCs synergistically accelerate healing, resulting in a reduced healing time. These observed healing effects demonstrated the potential of this multifunctional hydrogel to transform chronic wound care and improve patient outcomes.


Assuntos
Hidrogéis , Compostos de Manganês , Células-Tronco Mesenquimais , Óxidos , Cicatrização , Cicatrização/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Animais , Compostos de Manganês/química , Compostos de Manganês/farmacologia , Hidrogéis/química , Hidrogéis/farmacologia , Humanos , Óxidos/química , Óxidos/farmacologia , Diabetes Mellitus Experimental , Proliferação de Células/efeitos dos fármacos , Colágeno/química , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Alginatos/química , Alginatos/farmacologia , Masculino , Camundongos
12.
Biomacromolecules ; 25(5): 3098-3111, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38606583

RESUMO

Biodegradable stents are the most promising alternatives for the treatment of cardiovascular disease nowadays, and the strategy of preparing functional coatings on the surface is highly anticipated for addressing adverse effects such as in-stent restenosis and stent thrombosis. Yet, inadequate mechanical stability and biomultifunctionality limit their clinical application. In this study, we developed a multicross-linking hydrogel on the polylactic acid substrates by dip coating that boasts impressive antithrombotic ability, antibacterial capability, mechanical stability, and self-healing ability. Gelatin methacryloyl, carboxymethyl chitosan, and oxidized sodium alginate construct a double-cross-linking hydrogel through the dynamic Schiff base chemical and in situ blue initiation reaction. Inspired by the adhesion mechanism employed by mussels, a triple-cross-linked hydrogel is formed with the addition of tannic acid to increase the adhesion and antibiofouling properties. The strength and hydrophilicity of hydrogel coating are regulated by changing the composition ratio and cross-linking degree. It has been demonstrated in tests in vitro that the hydrogel coating significantly reduces the adhesion of proteins, MC3T3-E1 cells, platelets, and bacteria by 85% and minimizes the formation of blood clots. The hydrogel coating also exhibits excellent antimicrobial in vitro and antiinflammatory properties in vivo, indicating its potential value in vascular intervention and other biomedical fields.


Assuntos
Anti-Inflamatórios , Anticoagulantes , Bivalves , Poliésteres , Stents , Animais , Bivalves/química , Camundongos , Poliésteres/química , Poliésteres/farmacologia , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Stents/efeitos adversos , Anticoagulantes/química , Anticoagulantes/farmacologia , Gelatina/química , Hidrogéis/química , Hidrogéis/farmacologia , Quitosana/química , Quitosana/análogos & derivados , Quitosana/farmacologia , Alginatos/química , Alginatos/farmacologia , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Taninos/química , Taninos/farmacologia , Humanos , Metacrilatos
13.
Bioresour Technol ; 401: 130709, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38636877

RESUMO

Low-temperature could inhibit the performance of anaerobic granular sludge (AnGS). Quorum sensing (QS), as a communication mode between microorganisms, can effectively regulate AnGS. In this study, a kind of embedded particles (PVA/SA@Serratia) based on signal molecule secreting bacteria was prepared by microbial immobilization technology based on polyvinyl alcohol and sodium alginate to accelerate the recovery of AnGS system after low temperature. Low-temperature shock experiment verified the positive effect of PVA/SA@Serratia on restoring the COD removal rate and methanogenesis capacity of AnGS. Further analysis by metagenomics analysis showed that PVA/SA@Serratia stimulated higher QS activity and promoted the secretion of extracellular polymeric substance (EPS) in AnGS. The rapid construction of EPS protective layer effectively accelerated the establishment of a robust microbial community structure. PVA/SA@Serratia also enhanced multiple methanogenic pathways, including direct interspecies electron transfer. In conclusion, this study demonstrated that PVA/SA@Serratia could effectively strengthen AnGS after low-temperature shock.


Assuntos
Alginatos , Temperatura Baixa , Álcool de Polivinil , Percepção de Quorum , Esgotos , Alginatos/farmacologia , Alginatos/química , Álcool de Polivinil/química , Esgotos/microbiologia , Anaerobiose , Metano/metabolismo
14.
Biomacromolecules ; 25(5): 2953-2964, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38652682

RESUMO

Endoscopic submucosal dissection (ESD) is an effective method for resecting early-stage tumors in the digestive system. To achieve a low injection pressure of the injected fluid and continuous elevation of the mucosa following injection during the ESD technique, we introduced an innovative injectable sodium-alginate-based drug-loaded microsphere (Cipro-ThSA) for ESD surgery, which was generated through an emulsion reaction involving cysteine-modified sodium alginate (ThSA) and ciprofloxacin. Cipro-ThSA microspheres exhibited notable adhesiveness, antioxidant activity, and antimicrobial properties, providing a certain level of postoperative wound protection. In vitro cell assays confirmed the decent biocompatibility of the material. Lastly, according to animal experiments involving submucosal elevation of porcine colons, Cipro-ThSA microspheres ensure surgically removable lift height while maintaining the mucosa for approximately 246% longer than saline, which could effectively reduce surgical risks while providing sufficient time for operation. Consequently, the Cipro-ThSA microsphere holds great promise as a novel submucosal injection material, in terms of enhancing the operational safety and effectiveness of ESD surgery.


Assuntos
Alginatos , Ressecção Endoscópica de Mucosa , Microesferas , Alginatos/química , Animais , Suínos , Ressecção Endoscópica de Mucosa/métodos , Humanos , Ciprofloxacina/administração & dosagem , Ciprofloxacina/química , Ciprofloxacina/farmacologia , Cisteína/química
15.
Colloids Surf B Biointerfaces ; 238: 113905, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38593680

RESUMO

Hemostasis of deep irregular wounds is a severe problem in clinical practice. The development of rapid-acting hemostatic agents for deep and irregular wound is urgently needed. Here, sodium alginate/carboxycellulose/polydopamine (SA/CNF/PDA) microspheres was prepared by reverse emulsification and crosslinking with Ca2+, and SA/CNF/PDA composite hemostatic microspheres with porous structure were obtained by freeze-drying. SA/CNF/PDA composite hemostatic microspheres exhibited excellent porosity and water absorption which could rapidly absorb blood on the wound surface. Moreover, SA/CNF/PDA composite microspheres demonstrated remarkable hemostatic capabilities both in vitro and in vivo. It exhibited strong hemostatic performance in models of mouse tail-break and liver damage. Especially in liver injury model, it was completely hemostatic in 95 s, and blood loss (19.3 mg). The hemostatic efficacy of the SA/CNF/PDA composite microspheres was amplified through the stimulation of both exogenous and endogenous coagulation pathways. Therefore, SA/CNF/PDA composite hemostatic microspheres are suitable for rapid hemostasis of deep irregular wounds which are potential rapid hemostatic material for surgical application.


Assuntos
Alginatos , Hemostasia , Hemostáticos , Indóis , Microesferas , Polímeros , Alginatos/química , Alginatos/farmacologia , Animais , Camundongos , Polímeros/química , Polímeros/farmacologia , Hemostasia/efeitos dos fármacos , Hemostáticos/química , Hemostáticos/farmacologia , Indóis/química , Indóis/farmacologia , Masculino , Porosidade
16.
J Colloid Interface Sci ; 667: 54-63, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38615623

RESUMO

Type 1 diabetes mellitus (T1DM) is a chronic disease affecting millions worldwide. Insulin therapy is currently the golden standard for treating T1DM; however, it does not restore the normal glycaemic balance entirely, which increases the risk of secondary complications. Beta-cell therapy may be a possible way of curing T1DM and has already shown promising results in the clinic. However, low retention rates, poor cell survival, and limited therapeutic potential are ongoing challenges, thus increasing the need for better cell encapsulation devices. This study aimed to develop a mechanically reinforced vascular endothelial growth factor (VEGF)-delivering encapsulation device suitable for beta cell encapsulation and transplantation. Poly(l-lactide-co-ε-caprolactone) (PLCL)/gelatin methacryloyl (GelMA)/alginate coaxial nanofibres were produced using electrospinning and embedded in an alginate hydrogel. The encapsulation device was physically and biologically characterised and was found to be suitable for INS-1E beta cell encapsulation, vascularization, and transplantation in terms of its biocompatibility, porosity, swelling ratio and mechanical properties. Lastly, VEGF was incorporated into the hydrogel and the release kinetics and functional studies revealed a sustained release of bioactive VEGF for at least 14 days, making the modified alginate system a promising candidate for improving the beta cell survival after transplantation.


Assuntos
Alginatos , Gelatina , Hidrogéis , Células Secretoras de Insulina , Fator A de Crescimento do Endotélio Vascular , Hidrogéis/química , Alginatos/química , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/citologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator A de Crescimento do Endotélio Vascular/administração & dosagem , Gelatina/química , Animais , Poliésteres/química , Ratos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Diabetes Mellitus Tipo 1/terapia , Metacrilatos/química , Indutores da Angiogênese/química , Indutores da Angiogênese/farmacologia , Indutores da Angiogênese/administração & dosagem , Propriedades de Superfície
17.
Chemosphere ; 357: 141954, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38615964

RESUMO

Aerobic denitrification has emerged as a promising and efficient method for nitrogen removal from wastewater. However, the direct application of aerobic denitrifying bacteria has faced challenges such as low nitrogen removal efficiency, bacterial loss, and poor stability. To address these issues, this study developed a novel microbial particle carrier using NaHCO3-modified polyvinyl alcohol (PVA)/sodium alginate (SA) gel (NaHCO3-PVA/SA). This carrier exhibits several advantageous properties, including excellent mass transfer efficiency, favorable biocompatibility, convenient film formation, abundant biomass, and exceptional pollutant treatment capacity. The carrier was modified with 0.3% NaHCO3, 8.0% PVA, and 1.0% SA, resulting in a remarkable 3.4-fold increase in the average pore diameter and a 12.8% improvement in mass transfer efficiency. This carrier was utilized to immobilize the aerobic denitrifying bacterium Stutzerimonas stutzeri W-2 to enhance nitrogen removal (NaHCO3-PVA/SA@W-2), resulting in a NO3--N removal efficiency of 99.06%, which was 21.39% higher than that without modification. Compared with the non-immobilized W-2, the degradation efficiency was improved by 43.70%. After five reuses, the NO3--N and TN removal rates remained at 99% and 93.01%, respectively. These results provide a solid foundation for the industrial application of the modified carrier as an effective tool for nitrogen removal in large-scale wastewater treatment processes.


Assuntos
Alginatos , Desnitrificação , Nitrogênio , Álcool de Polivinil , Águas Residuárias , Álcool de Polivinil/química , Alginatos/química , Nitrogênio/metabolismo , Águas Residuárias/química , Águas Residuárias/microbiologia , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/metabolismo , Aerobiose , Pseudomonas stutzeri/metabolismo , Biodegradação Ambiental , Células Imobilizadas/metabolismo
18.
Int J Biol Macromol ; 267(Pt 1): 131450, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38588838

RESUMO

With the increasing severity of energy shortages and environmental pollution, there is an urgent need for advanced thermal insulation materials with excellent comprehensive performance, including low thermal conductivity, high flame resistance, and strong compressive strength. Herein, an anisotropic composite aerogel based on cellulose nanofibers (CNF), calcium alginate (CA), and boric acid (BA) is fabricated using a directional freeze-drying strategy. The CA and BA, as double cross-linking agents, associated with oriented porous structure provide the resultant aerogel with good mechanical strength. Additionally, self-flame retardant CA and BA act as synergistic flame retardants that endow the aerogel with excellent flame retardance properties such as a limiting oxygen index value of 44.2 %, UL-94 V-0 rating, and low heat release. Furthermore, this composite aerogel exhibits outstanding thermal insulation performance with a low thermal conductivity of approximately 30 mW m-1 K-1. Therefore, the composite aerogel is expected to have a wide potential application in areas such as construction, automotive industry, batteries, petrochemical pipelines, and high-temperature reaction devices.


Assuntos
Alginatos , Ácidos Bóricos , Celulose , Retardadores de Chama , Géis , Nanofibras , Condutividade Térmica , Nanofibras/química , Ácidos Bóricos/química , Celulose/química , Alginatos/química , Géis/química , Anisotropia , Porosidade
19.
Int J Biol Macromol ; 267(Pt 1): 131483, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38599426

RESUMO

Probiotics are susceptible to diverse conditions during processing, storage, and digestion. Here, shellac (SC), sodium alginate (SA), coconut oil (CO), soybean oil (SO), and trehalose (AL) were used to prepare microcapsules aiming to improve the survival of Lactiplantibacillus plantarum KLDS1.0318 during freeze-drying, storage process, and gastrointestinal digestion. The results showed that for SA/AL/SC/CO and SA/AL/SC/SO, the survival loss decreased by 51.2 % and 51.0 % after a freeze-drying process compared with microcapsules embedded by SA; the viable bacteria count loss decreased by 4.36 and 4.24 log CFU/mL compared with free cell (CON) during storage for 28 d under 33%RH at 25 °C, respectively; while for simulating digestion in vitro, the survival loss decreased by 3.05 and 2.70 log CFU/mL, 0.63 and 0.55 log CFU/mL after digestion at simulated gastric fluid for 120 min and small intestine fluid for 180 min, respectively (P < 0.05). After microcapsules were added to fermented dairy stored at 4 °C for 21 d, the viable bacteria count of SA/AL/SC/CO and SA/AL/SC/SO significantly increased by 2.10 and 1.70 log CFU/mL compared with CON, respectively (P < 0.05). In conclusion, the current study indicated that shellac-based probiotic microcapsules have superior potential to protect and deliver probiotics in food systems.


Assuntos
Alginatos , Cápsulas , Digestão , Liofilização , Viabilidade Microbiana , Probióticos , Alginatos/química , Viabilidade Microbiana/efeitos dos fármacos , Trato Gastrointestinal/microbiologia , Trealose/química , Óleo de Soja/química , Óleo de Coco/química
20.
Int J Biol Macromol ; 267(Pt 1): 131485, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38604429

RESUMO

Global seafood consumption is estimated at 156 million tons annually, with an economic loss of >25 billion euros annually due to marine fish spoilage. In contrast to traditional smart packaging which can only roughly estimate food freshness, an intelligent platform integrating machine learning and smart aerogel can accurately predict remaining shelf life in food products, reducing economic losses and food waste. In this study, we prepared aerogels based on anthocyanin complexes that exhibited excellent environmental responsiveness, high porosity, high color-rendering properties, high biocompatibility, high stability, and irreversibility. The aerogel showed excellent indication properties for rainbow trout and proved suitable for fish storage environments. Among the four machine learning models, the radial basis function neural network and backpropagation network optimized by genetic algorithm demonstrated excellent monitoring performance. Also, the two-channel dataset provided more comprehensive information and superior descriptive capability. The three-layer structure of the monitoring platform provided a new paradigm for intelligent and sophisticated food packaging. The results of the study might be of great significance to the food industry and sustainable development.


Assuntos
Alginatos , Antocianinas , Colorimetria , Embalagem de Alimentos , Géis , Antocianinas/química , Embalagem de Alimentos/métodos , Alginatos/química , Géis/química , Colorimetria/métodos , Animais , Porosidade , Alimentos Marinhos/análise , Oncorhynchus mykiss , Aprendizado de Máquina
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