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1.
Georgian Med News ; (311): 136-142, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33814407

RESUMO

Ventral hernias, with the incidence of reherniation nearly as high as 50%, still remain to be a real challenge for surgeons worldwide. The use of mesh in the repair of abdominal wall defects reduces the incidence of reherniation; however, using a prosthetic mesh can lead to complications like wound infection, hematoma, seroma, enterocutaneous fistula, small bowel obstruction, recurrent herniation and erosion into adjacent structures including the intestine. The aim of the study was to develop a method for producing gelatin-coated decellularized and lyophilized human amniotic membrane graft and to determine its effectiveness for the reconstruction of the anterior abdominal wall defects. Experiments were conducted on 40 Lewis white laboratory rats. Animals were divided into four equivalent groups. Abdominal wall defects were created in all rats and repaired using the ULTRAPROTM mesh (group I), ULTRAPROTM mesh which was covered by decellularized and lyophilized human amniotic membrane from both sides (group II), mesh from gelatin-coated decellularized and lyophilized human amniotic membrane (group III) and biological surgical mesh XI-S+® (group IV). Three months after implantation, meshes from gelatin-coated decellularized and lyophilized human amniotic membrane were integrated with host tissues so that it was difficult to distinguish it from the surrounding tissues. However, in the second group, ULTRAPROTM mesh was still detectable through the decellularized amniotic membrane. Encouraging results were also observed when using a XI-S+® graft. Three months after implantation, XI-S+® graft was surrounded by a well-defined connective tissue capsule and was tightly fixed to the host tissues. While using gelatin-coated decellularized and lyophilized human amniotic membrane grafts and XI-S+® grafts, all the defects were repaired successfully and none of the rats in these groups showed any evidence of bulging or herniation, development of wound rupture, wound infection or fistula formation in postoperative period. Gelatin-coated Decellularized human amniotic membrane can be used as anti-adhesive barrier in abdominal and pelvic surgery, as well as for the repair of the abdominal wall hernia.


Assuntos
Parede Abdominal , Hérnia Ventral , Parede Abdominal/cirurgia , Âmnio , Animais , Gelatina , Humanos , Ratos , Ratos Endogâmicos Lew , Telas Cirúrgicas
2.
Food Chem ; 351: 129347, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-33647702

RESUMO

In this study, two active packaging types were produced: single-layer biopolymer films with a polysaccharide - furcellaran and carp skin gelatin hydrolysate; two-layer films with identical composition, but synthetic peptide Alanina-Tyrosine addition. The procedure objective was multiplying antioxidant effects of the hydrolysate complexed with furcellaran. Films were used on Atlantic mackerel (storage 4 °C, 15 days); samples were analysed for changes in microbiological quality, TVB-N, biogenic amine content, fatty acid composition, TBARS. Consumer analysis was performed characterising mackerel carcass perception depending on implemented active coatings. The developed innovative single- and double-layer coatings effectively slow down lipid oxidation processes, especially at the initial period of Atlantic mackerel storage in refrigerated conditions. The coatings effectively inhibited microorganism growth, extending shelf-life by 2 days, single-layer coatings showing greater efficiency. According to consumers, coating application did not adversely affect product attractiveness parameters. The developed innovative coatings show great applicative potential as a new active packaging for perishable foods.


Assuntos
Alginatos/química , Antioxidantes/química , Carpas/anatomia & histologia , Embalagem de Alimentos/métodos , Gelatina/química , Peptídeos/química , Gomas Vegetais/química , Pele/química , Animais , Hidrólise , Oxirredução , Perciformes , Alimentos Marinhos/análise
3.
Methods Mol Biol ; 2265: 47-63, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33704704

RESUMO

In order to protrude within a dense tissue, tumor cells have to develop the ability to digest the extracellular matrix (ECM). Melanoma cells, similarly to other types of tumor cells, form invadopodia, membranous invaginations rich in filamentous actin and several other proteins including matrix metalloproteinases (MMPs). MMPs degrade ECM structural proteins such as collagens, fibronectin, or laminin. Here we describe an assay that allows the detection of gelatinase activity exhibited by tumor cells under 2D conditions and methods to present obtained data in both a quantitative and a qualitative manner.


Assuntos
Matriz Extracelular/enzimologia , Gelatina/metabolismo , Melanoma/enzimologia , Microscopia Confocal/métodos , Actinas/metabolismo , Técnicas de Cultura de Células/métodos , Linhagem Celular Tumoral , Matriz Extracelular/metabolismo , Matriz Extracelular/patologia , Fluorescência , Gelatinases/metabolismo , Humanos , Metaloproteinases da Matriz/metabolismo , Melanoma/patologia , Imagem Óptica , Podossomos/enzimologia , Podossomos/metabolismo , Podossomos/patologia
4.
Carbohydr Polym ; 260: 117801, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33712149

RESUMO

Slowly digestible starches have received interest due to their lower increase of postprandial blood glucose and insulin levels and, hence, modification of starches towards slower digestibility has commercial interest. However, chemical characteristics driving enzymatic (digestive) degradation are not fully unraveled. The digestion properties of starches have been linked to their crystalline type, chain length distribution, amylose content or degree of branching, but content and length of relatively long side-chains in amylopectin has not been paid attention to. Therefore, this research focusses on the unique content and length of amylopectin side-chains from conventional and new starch sources (potato, corn, pea, and tulip) correlated to the enzymatic digestion. The rate of hydrolysis was found to be correlated with the crystalline type of starch, as previously suggested, however, the complete hydrolysis of all starches, independent of the crystalline type and source, was shown to be governed by the content of longer amylopectin chains.


Assuntos
Gelatina/química , Glucana 1,4-alfa-Glucosidase/metabolismo , Amido/metabolismo , alfa-Amilases/metabolismo , Cristalização , Digestão , Hidrólise , Espectroscopia de Ressonância Magnética , Ervilhas/metabolismo , Solanum tuberosum/metabolismo , Amido/química , Zea mays/metabolismo
5.
Int J Mol Sci ; 22(4)2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33669209

RESUMO

Nisin Z, an amphipathic peptide, with a significant antibacterial activity against Gram-positive bacteria and low toxicity in humans, has been studied for food preservation applications. Thus far, very little research has been done to explore its potential in biomedicine. Here, we report the modification of sodium alginate (SA) and gelatin (GN) blended microfibers, produced via the wet-spinning technique, with Nisin Z, with the purpose of eradicating Staphylococcus aureus-induced infections. Wet-spun SAGN microfibers were successfully produced at a 70/30% v/v of SA (2 wt%)/GN (1 wt%) polymer ratio by extrusion within a calcium chloride (CaCl2) coagulation bath. Modifications to the biodegradable fibers' chemical stability and structure were then introduced via crosslinking with CaCl2 and glutaraldehyde (SAGNCL). Regardless of the chemical modification employed, all microfibers were labelled as homogeneous both in size (≈246.79 µm) and shape (cylindrical and defect-free). SA-free microfibers, with an increased surface area for peptide immobilization, originated from the action of phosphate buffer saline solution on SAGN fibers, were also produced (GNCL). Their durability in physiological conditions (simulated body fluid) was, however, compromised very early in the experiment (day 1 and 3, with and without Nisin Z, respectively). Only the crosslinked SAGNCL fibers remained intact for the 28 day-testing period. Their thermal resilience in comparison with the unmodified and SA-free fibers was also demonstrated. Nisin Z was functionalized onto the unmodified and chemically altered fibers at an average concentration of 178 µg/mL. Nisin Z did not impact on the fiber's morphology nor on their chemical/thermal stability. However, the peptide improved the SA fibers (control) structural integrity, guaranteeing its stability for longer, in physiological conditions. Its main effect was detected on the time-kill kinetics of the bacteria S. aureus. SAGNCL and GNCL loaded with Nisin Z were capable of progressively eliminating the bacteria, reaching an inhibition superior to 99% after 24 h of culture. The peptide-modified SA and SAGN were not as effective, losing their antimicrobial action after 6 h of incubation. Bacteria elimination was consistent with the release kinetics of Nisin Z from the fibers. In general, data revealed the increased potential and durable effect of Nisin Z (significantly superior to its free, unloaded form) against S. aureus-induced infections, while loaded onto prospective biomedical wet-spun scaffolds.


Assuntos
Alginatos/química , Antibacterianos/química , Antibacterianos/farmacologia , Reagentes para Ligações Cruzadas/química , Gelatina/química , Nisina/análogos & derivados , Staphylococcus aureus/efeitos dos fármacos , Materiais Biocompatíveis/química , Plásticos Biodegradáveis/química , Biopolímeros/química , Cloreto de Cálcio/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Glutaral/química , Cinética , Testes de Sensibilidade Microbiana , Nisina/química , Nisina/farmacologia , Porosidade , Solubilidade , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Água/química
6.
Zhongguo Zhong Yao Za Zhi ; 46(3): 591-598, 2021 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-33645024

RESUMO

Nano-LC MS/MS was used to analyze trypsin digested deer-hide gelatin(DHG) samples, hydroxylation and O-glycosylation on lysine sites of DHG were comprehensive identified by using PEAKS Studio software. The sites, sorts and amounts of hydroxylation and O-glycosylation on Type Ⅰ collagen α1 chain(COL1 A1) and α2 chain(COL1 A2) of DHG were revealed. As a result, 5 284 peptides were identified from DHG samples, which were mainly from COL1 A1 and COL1 A2. Among these peptides, there were 449 peptides with hydroxylysine, 442 with galactosyl-hydroxylysine, 449 with glucosyl-galactosyl-hydroxylysine. The major modified sites of hydroxylation and O-glycosylation in DHG were shown as follow: α1-9 N and α2-5 N in N-telopeptides, α1-87, α1-174, α1-930, α2-87, α2-174, α2-933 in triple helix domain, and α1-16 C in C-telopeptides. These hydroxylation and O-glycosylation were correlated with the formation and stability of collagen molecules and collagen fibrils. It is feasible for the collagens and peptides dissolving from deer skin collagen fibrils under high temperature and pressure decocting, high temperature and pressure also might destroy inter-molecular covalent cross-linking and help those glycol-peptides formations. The present study provided ideas and strategies for the in-depth investigation on DHG chemical constituents, and showed good theoretical significance and application value.


Assuntos
Cervos , Lisina , Animais , Cervos/metabolismo , Gelatina , Glicosilação , Hidroxilação , Lisina/metabolismo , Processamento de Proteína Pós-Traducional , Espectrometria de Massas em Tandem
7.
Int J Mol Sci ; 22(5)2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33652991

RESUMO

A hydrogel system based on oxidized alginate covalently crosslinked with gelatin (ADA-GEL) has been utilized for different biofabrication approaches to design constructs, in which cell growth, proliferation and migration have been observed. However, cell-bioink interactions are not completely understood and the potential effects of free aldehyde groups on the living cells have not been investigated. In this study, alginate, ADA and ADA-GEL were characterized via FTIR and NMR, and their effect on cell viability was investigated. In the tested cell lines, there was a concentration-dependent effect of oxidation degree on cell viability, with the strongest cytotoxicity observed after 72 h of culture. Subsequently, primary human cells, namely fibroblasts and endothelial cells (ECs) were grown in ADA and ADA-GEL hydrogels to investigate the molecular effects of oxidized material. In ADA, an extremely strong ROS generation resulting in a rapid depletion of cellular thiols was observed in ECs, leading to rapid necrotic cell death. In contrast, less pronounced cytotoxic effects of ADA were noted on human fibroblasts. Human fibroblasts had higher cellular thiol content than primary ECs and entered apoptosis under strong oxidative stress. The presence of gelatin in the hydrogel improved the primary cell survival, likely by reducing the oxidative stress via binding to the CHO groups. Consequently, ADA-GEL was better tolerated than ADA alone. Fibroblasts were able to survive the oxidative stress in ADA-GEL and re-entered the proliferative phase. To the best of our knowledge, this is the first report that shows in detail the relationship between oxidative stress-induced intracellular processes and alginate di-aldehyde-based bioinks.


Assuntos
Alginatos/química , Materiais Biocompatíveis/química , Células Endoteliais/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Gelatina/química , Estresse Oxidativo/efeitos dos fármacos , Alginatos/toxicidade , Animais , Materiais Biocompatíveis/toxicidade , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células Endoteliais/citologia , Fibroblastos/citologia , Gelatina/toxicidade , Humanos , Camundongos , Células NIH 3T3 , Tecidos Suporte/química
8.
J Biomed Nanotechnol ; 17(2): 242-252, 2021 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-33785095

RESUMO

Sericin, a silk protein, has a high potential for use as an extracellular matrix in tissue engineering applications. In this study, novel gelatin (GEL) and silk sericin (SS) were incorporated with a polyvinyl alcohol) PVA hydrogel nanocomposite (GEL-SS-PVA) scaffold that can be applied to repair cartilage. Glutaraldehyde was used as a cross-linking agent, with hydrochloric acid acting as an initiator. The microstructure characteristics of the obtained GEL-SS and GEL-SS-PVA scaffolds were also examined using FTIR and XRD spectra and their enhanced thermal stability was assessed by TGA. The blended GEL-SS and GEL-SS-PVA scaffolds were confirmed by SEM analysis to be highly porous with optimum pore sizes of 172 and 58 µm, respectively. Smaller pore sizes and improved uniformity were observed as the concentration of PVA in the GEL-SS-PVA scaffold increased. PVA decreased the tensile strength and elongation of the membranes but increased the modulus. Swelling studies showed high swellability and complete degradation in the presence of phosphate-buffered saline. Cytocompatibility of the GEL-SS-PVA scaffolds showed that these had the highest potential to promote cell proliferation as evaluated with standard microscopy using L929 fibroblasts. The prepared GEL-SS composite scaffold incorporated with the PVA hydrogel was implanted in full-thickness articular cartilage defects in rats. The repair effect of cartilage defects was observed and evaluated among the GEL-SS-PVA, GEL-SS, and control operation groups. The defects were almost completely repaired after 14 weeks in the GEL-SS-PVA group, thereby indicating that the GEL-SS-PVA composite had a favorable effect on articular cartilage defects in rat knee joint repair.


Assuntos
Cartilagem Articular , Nanocompostos , Sericinas , Animais , Gelatina , Hidrogéis , Articulação do Joelho , Álcool de Polivinil , Ratos , Seda , Engenharia Tecidual , Tecidos Suporte
9.
Molecules ; 26(4)2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33669650

RESUMO

Apples are an important source of biologically active compounds. Consequently, we decided to model hard gelatin capsules with lyophilized apple powder by using different excipients and to evaluate the release kinetics of phenolic compounds. The apple slices of "Ligol" cultivar were immediately frozen in a freezer (at -35°C) with air circulation and were lyophilized with a sublimator at the pressure of 0.01 mbar (condenser temperature, -85°C). Lyophilized apple powder was used as an active substance filled into hard gelatin capsules. We conducted capsule disintegration and dissolution tests to evaluate the quality of apple lyophilizate-containing capsules of different encapsulating content. Individual phenolic compounds can be arranged in the following descending order according to the amount released from the capsules of different compositions: chlorogenic acid > rutin > avicularin > hyperoside > phloridzin > quercitrin > (-)-epicatechin > isoquercitrin. Chlorogenic acid was the compound that was released in the highest amounts from capsules of different encapsulating content: its released amounts ranged from 68.4 to 640.3 µg/mL. According to the obtained data, when hypromellose content ranged from 29% to 41% of the capsule mass, the capsules disintegrated within less than 30 min, and such amounts of hypromellose did not prolong the release of phenolic compounds. Based on the results of the dissolution test, the capsules can be classified as fast-dissolving preparations, as more than 85% of the active substances were released within 30 min.


Assuntos
Produtos Biológicos/análise , Cápsulas/química , Liofilização , Malus/química , Etanol/química , Gelatina/química , Glicosídeos/química , Fenóis/análise , Fenóis/química , Pós
10.
Food Chem ; 351: 129226, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-33639430

RESUMO

The effect of three drying methods (hot air, freeze and spray drying) on the solubility and amphiphilicity of gelatin were investigated and compared. Results showed spray drying gelatin (SDG) and hot air drying gelatin (HDG) showed the lowest and best solubility, respectively. This phenomenon was attributed to the degree of subunits degradation and hydrophobicity. The HDG showed an obvious degradation during the hot air drying and displayed the strongest hydrophilicity, while SDG showed a slight degradation and strongest hydrophobicity. The results of wettability showed that SDG had a better amphiphilicity (92.48°) in comparison with HDG (57.7°) and freeze drying gelatin (VDG, 77.53°), which can effectively reduce the interfacial tension of gelatin, thus significantly improving the stability of foam and emulsion (p < 0.05). These results suggested the drying methods can adjust the amphiphilicity of gelatin, and the SDG displayed a better amphiphilicity, showing good potential applications in foam and emulsion.


Assuntos
Dessecação/métodos , Congelamento , Gelatina/química , Gelatina/isolamento & purificação , Interações Hidrofóbicas e Hidrofílicas , Micro-Ondas , Solubilidade , Fatores de Tempo , Molhabilidade
11.
Food Chem ; 351: 129269, 2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-33640772

RESUMO

Chemical modifications of gelatin from mechanically separated chicken meat (MSM) residue were practiced using caffeic acid as a cross-linker. The effects of oxidation period (OP), cross-linking temperature (CT), and caffeic acid (CA) concentration were investigated. Experiments were performed using Response Surface Methodology (RSM). The effects of 16 different cross-linking modifications on the physicochemical properties of chicken gelatin gels were investigated. Maximum gel strength was determined at 12.5 min OP, 50 °C CT and 2.5% CA concentration and this was 63% higher than the control (uncross-linked chicken gelatin). Temperature has an increasing effect on the degree of cross-linking value up to a certain degree. The highest degree of cross-linking was observed at between 50° and 55 °C. The color characteristics of gels were affected by cross-linking having more brown color. Overall this study demonstrated that caffeic acid has a potential to be an efficient natural cross-linking factor increasing the mechanical properties of chicken gelatin thermo-irreversibly.


Assuntos
Ácidos Cafeicos/química , Gelatina/química , Animais , Galinhas , Oxirredução , Temperatura
12.
Food Funct ; 12(5): 1983-1995, 2021 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-33537688

RESUMO

To evaluate the effect of young apple polyphenols (YAP) on starch digestion and gut microbiota, complexes of native wheat starch (NWS) with YAP, and their main components chlorogenic acid (CA) and phlorizin (P) were fabricated and gelatinized. Through XRD and FTIR analysis, it was found that the partial crystalline structure of NWS was destroyed during gelatinization, and the addition of P decreased the extent of destruction. Then, the gelatinized starchy samples were subjected to in vitro digestion. The wheat starch (WS)-phenolic compound complexes significantly suppressed the digestion rate and increased the proportion of resistant starch (RS) in WS. Furthermore, the residual starchy components after digestion were fermented by human fecal samples for 24 h. The WS-YAP complex greatly increased the concentration of short-chain fatty acids (SCFAs), especially acetic and propionic acids, and enhanced the growth of health-promoting gut microbiota such as Prevotella. Conclusively, YAP was shown to play a positive role in maintaining blood glucose balance and intestinal health.


Assuntos
Digestão/efeitos dos fármacos , Fermentação/efeitos dos fármacos , Malus/química , Polifenóis/farmacologia , Amido/metabolismo , Triticum/química , Adulto , Bactérias/classificação , Bactérias/metabolismo , Cristalização , Ácidos Graxos/metabolismo , Ácidos Graxos Voláteis/metabolismo , Fezes/microbiologia , Frutas/química , Gelatina/química , Humanos , Amido/química , alfa-Amilases/metabolismo
13.
Food Chem ; 349: 129170, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33548887

RESUMO

In this study, potato, lotus seed and wheat starch samples with different degree of gelatinization (DG) were prepared and their in vitro digestibility at low α-amylase activity evaluated by measuring the release of reducing sugar. The hydrolysis rate (k) and the final equilibrium concentration (C∞) of the three starches increased with increasing DG. Kinetic analyses showed that the Michaelis-Menten constant (Km) and the catalytic efficiency (kcat/Km) increased with increasing DG, indicative of the increasing affinity and catalytic efficiency of α-amylase with all three starch samples. Of the three starches, lotus seed starch showed a much greater increase in k and kcat/Km than potato and wheat starches as the DG of starch increased. From this study, we concluded that at low activity of α-amylase, DG is a major determinant for the binding affinity and catalytic efficiency of α-amylase to starch and in turn the digestion rate of starch.


Assuntos
Digestão , Amido/metabolismo , alfa-Amilases/metabolismo , Catálise , Cristalização , Gelatina/metabolismo , Hidrólise , Técnicas In Vitro , Cinética , Lotus/embriologia , Sementes/metabolismo , Solanum tuberosum/química , Especificidade por Substrato
14.
Food Chem ; 349: 129159, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33545604

RESUMO

The effect of dry heat (DH, 130 °C, 1, 3 and 9 h), cold plasma (CP, 40 V, 1, 5 and 10 min) and their combination (D-P) treatment on the structure, physicochemical and digestive properties of red adzuki bean starch were studied. The results showed that DH or CP had slight change in morphology while diffraction pattern of starch was remained. With the extension of treated time of DH and CP, the amylose content, crystallinity, molecular weight, short-range order, the long chain of amylopectin, enthalpy value, swelling power, digestibility were reduced, while gelatinization temperatures, the short chain of amylopectin and solubility were increased. The D-P had deeper modification than the single treatment. The combination of dry heat and cold plasma is a simple and green method to improve the starch structure and enhance starch properties and this modified starch could be implemented to tailor starch to the desired food applications.


Assuntos
Temperatura Baixa , Digestão , Temperatura Alta , Gases em Plasma/química , Amido/química , Amido/metabolismo , Vigna/química , Manipulação de Alimentos , Gelatina/química , Peso Molecular , Solubilidade , Termodinâmica
15.
Methods Mol Biol ; 2273: 263-278, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33604860

RESUMO

Tissue engineering is an elegant tool to create organs in vitro, that can help obviate the lack of organ donors in transplantation medicine and provide the opportunity of studying complex biological systems in vitro, thereby reducing the need for animal experiments. Artificial intestine models are at the core of Fish-AI, an EU FET-Open research project dedicated to the development of a 3D in vitro platform that is intended to enable the aquaculture feed industry to predict the nutritional and health value of alternative feed sources accurately and efficiently.At present, it is impossible to infer the health and nutrition value through the chemical characterization of any given feed. Therefore, each new feed must be tested through in vivo growth trials. The procedure is lengthy, expensive and requires the use of many animals. Furthermore, although this process allows for a precise evaluation of the final effect of each feed, it does not improve our basic knowledge of the cellular and molecular mechanisms determining such end-results. In turn, this lack of mechanistic knowledge severely limits the capacity to understand and predict the biological value of a single raw material and of their different combinations.The protocol described herein allows to develop the two main components essential to produce a functional platform for the efficient and reliable screening of feeds that the feed industry is currently developing for improving their health and nutritional value. It is here applied to the Rainbow Trout, but it can be fruitfully used to many other fish species.


Assuntos
Técnicas de Cultura de Células/métodos , Gelatina/química , Mucosa Intestinal/citologia , Oncorhynchus mykiss , Tecidos Suporte/química , Acrilamidas/química , Ração Animal/análise , Animais , Aquicultura/métodos , Materiais Biocompatíveis/química , Separação Celular/métodos , Células Cultivadas , Norbornanos/química , Oncorhynchus mykiss/crescimento & desenvolvimento
16.
Food Chem ; 345: 128865, 2021 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-33601664

RESUMO

To enhance the physicochemical stability of ω-3 PUFAs concentrates from fish oil, biopolymer coating based on chitosan (CH) and gelatin (GE) deposited on the surface of nanoliposomes (NLs) has been synthesized and characterized. The mean particle size of surface-decorated nanoliposomes (SDNLs) containing ω-3 PUFAs concentrates was found to be in the range of 209.5-454.3 nm. Scanning and transmission electron microscopy revealed the spherical shape and smooth surface of the nanovesicles. Fourier-transform infrared spectroscopy and X-ray diffraction observations confirmed that the NLs have been successfully coated by biopolymeric blends. The highest entrapment efficiency of 81.6% was obtained in polymer-stabilized NLs with a concentration ratio of 0.3:0.1 (CH:GE). Differential scanning calorimetry results revealed enhanced thermal stability of vesicles after polymeric blend desorption. Finally, the oxidative stability assays demonstrated that the ω-3 PUFAs concentrates entrapped in SDNLs was protected against oxidation in comparison to the free ω-3 PUFAs concentrates.


Assuntos
Quitosana/química , Ácidos Graxos Ômega-3/química , Gelatina/química , Lipossomos/química , Nanoestruturas/química , Cromatografia Gasosa , Estabilidade de Medicamentos , Ácidos Graxos Ômega-3/análise , Óleos de Peixe/química , Oxirredução , Tamanho da Partícula , Temperatura de Transição , Ureia/química
17.
Spine (Phila Pa 1976) ; 46(4): E243-E249, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33475276

RESUMO

STUDY DESIGN: An in vitro experimental study testing a Gelatin-poly (γ-glutamic acid) hydrogel for disc repair. OBJECTIVE: To evaluate the cytocompatibility and degradability of the above mentioned hydrogel for intervertebral disc annular fibrosis (AF) repair. SUMMARY OF BACKGROUND DATA: No repair strategies for correcting annular defects in lumbar discectomy have been clinically well recognized. Exogenous supplementation of regenerative materials to fill defects is a minimally invasive way to restore compromised mechanical properties. The injected materials, most commonly gelatin-based materials with cross-linking agents, serve as sealants and as a scaffold for incorporating biomaterials for augmentation. However, cytotoxicity of hydrogel crosslinking agents is of concern in developing viable materials. METHODS: This in vitro experimental study evaluated a newly developed gelatin-based hydrogel for intervertebral disc AF repair. Mechanical strength was augmented by γ-PGA, and 1-(3-dimethylaminopropyl)-3-ethyl-carbodiimide hydrochloride (EDC) was used for material crosslinking. Isolated bovine tail intervertebral discs (IVDs) were used to test the hydrogel, and hydrogel surface monolayer AF cell culture was used to investigate efficacy in hydrogel constructs of different EDC concentrations. Cell metabolic activity was evaluated with Alamar blue assay, cell viability assay with live/dead stain, and sulfated glycosaminoglycan (GAG) and double strain DNA were quantified to evaluate proliferation of implanted cells and synthesis of extracellular matrix (ECM) proteins. RESULTS: EDC concentrations from 10 to 40 mM resulted in significant decreases in AF cell proliferation without obvious influence on cell viability. Higher EDC concentrations resulted in decreased percentage of Alamar blue reduction and GAG and DNA concentration, but did not affect GAG/DNA and live-dead ratios. Degradation tests revealed that higher EDC concentrations decreased the hydrogel degradation rate. CONCLUSION: The developed gelatin-poly (γ-PGA) hydrogel with 20 mM EDC concentration provides an effective gap-filling biomaterial with good cytocompatibility, suggesting substantial promise for use as a sealant for small AF defects.Level of Evidence: N/A.


Assuntos
Adesivos/uso terapêutico , Gelatina/farmacologia , Ácido Glutâmico/farmacologia , Degeneração do Disco Intervertebral/tratamento farmacológico , Disco Intervertebral/efeitos dos fármacos , Animais , Anel Fibroso/cirurgia , Materiais Biocompatíveis , Bovinos , Células Cultivadas , Discotomia , Ácido Glutâmico/metabolismo , Glicosaminoglicanos , Hidrogéis , Disco Intervertebral/cirurgia , Degeneração do Disco Intervertebral/cirurgia , Ácido Poliglutâmico/análogos & derivados
18.
Food Chem ; 348: 129093, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-33503534

RESUMO

Fish gelatin (FG) has been extensively studied as a potential substitute for mammal gelatin. However, FG often requires different modification methods to change its physical and chemical properties due to its low gelling properties. Here, γ-polyglutamic acid (γ-PGA) and microbial transglutaminase (MTGase) were combined to modify FG to improve its gelling properties. The γ-PGA at 0.04% (w/v) and MTGase of different concentrations (0.02-0.08%, w/v) were used to modify FG, and the effects of complex modification on the gelling properties and structure of FG were studied. When the MTGase content was 0.08% (w/v), FG had the best gelling properties. In addition, the complex modification of MTGase and γ-PGA hindered the formation of the triple helix during the FG gel process. This reduced the gel rate, but significantly increased its viscosity. A schematic model was also proposed to illustrate the complex modifications of FG by MTGase and γ-PGA.


Assuntos
Peixes , Gelatina/química , Ácido Poliglutâmico/análogos & derivados , Reologia , Transglutaminases/química , Animais , Géis , Ácido Poliglutâmico/química , Viscosidade
19.
Int J Biol Macromol ; 171: 262-274, 2021 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-33421466

RESUMO

The active emulsified blend films based on gelatin-pectin (5% w/w) containing virgin olive oil (VOO) (0.1-0.3 g/g biopolymer) and grape seed oil (GSO) (0.1-0.3 g/g biopolymer) were prepared by casting method. GSO showed slightly more decreasing effect than VOO on ultimate tensile strength (UTS) and strain at break (SAB) of blend films however; VOO had more reducing effect than GSO on the water vapor permeability (WVP). The scanning electron microscopy (SEM) images showed that incorporating 0.3 g GSO and VOO oils had not considerable effect on the morphology of the emulsified films. Atomic force microscopy (AFM) topography images indicated that adding of oils considerably could increase roughness of emulsified film. Fourier transforms infrared (FTIR) revealed that no new chemical bond formed by adding oils into biopolymer matrix. The minimum inhibitory concentration (MIC) of VOO, GSO and Savory essential oil (SEO) against four important spoilage bacteria showed that GSO had higher antibacterial effect than VOO however; both showed very lower antimicrobial effect than SEO. All active films showed lower inhibitory zone for S. aureus than S. typhimurium and P. fluorescence. The chicken breast fillets wrapped in the films containing VOO-GSO-SEO (0.15-0.15-0.02 g/g polymer) showed considerably lower total viable count (TVC), Pseudomonas spp., Enterobacteriaceae, E. coli 157:H7 and S. typhimurium count than the control one during 12 days storage. Also, it caused significant decrease in peroxide value (PV), thiobarbituric acid reactive substances (TBARS) and total volatile basic nitrogen (TVB-N) of fillet samples.


Assuntos
Anti-Infecciosos/farmacologia , Embalagem de Alimentos , Gelatina/efeitos dos fármacos , Extrato de Sementes de Uva/química , Manufaturas , Óleos Voláteis/farmacologia , Azeite de Oliva/farmacologia , Pectinas/farmacologia , Óleos Vegetais/farmacologia , Animais , Galinhas , Emulsões , Gelatina/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Teste de Materiais , Carne/análise , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Nitrogênio/análise , Permeabilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Vapor , Resistência à Tração , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Vitis/química
20.
Int J Biol Macromol ; 172: 580-588, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33476616

RESUMO

Tissue adhesives have been developed for sealing tissue damaged in surgery. Among these, sheet-type adhesives require a relatively long time to adhere to biological tissue under wet conditions. To address this clinical problem, we fabricated a tissue-adhesive fiber sheet (AdFS) based on decanyl group (C10) modified Alaska pollock-derived gelatin (C10-ApGltn) using electrospinning. Ultraviolet (UV) irradiation of the AdFS was performed to increase the affinity between the AdFS and wet biological tissue by introducing hydrophilic functional groups. The UV irradiated AdFS (UV-C10-AdFS) strongly adhered to porcine pleura within 2 min under wet conditions and showed higher burst strength compared with the original ApGltn (Org-ApGltn) sheet. Hematoxylin-eosin stained sections revealed that a dense UV-C10-AdFS layer remained on the surface of the porcine pleura even after burst strength measurement. Moreover, UV-C10-AdFS has excellent cytocompatibility and efficiently supports the growth of L929 cells. UV-C10-AdFS is a promising adhesive material for sealing wet biological tissue.


Assuntos
Gelatina/química , Pleura/efeitos dos fármacos , Adesivos Teciduais/química , Adesivos Teciduais/efeitos da radiação , Alaska , Animais , Linhagem Celular , Técnicas Eletroquímicas , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Gadiformes/metabolismo , Gelatina/efeitos da radiação , Interações Hidrofóbicas e Hidrofílicas , Teste de Materiais , Camundongos , Pleura/efeitos da radiação , Polietilenoglicóis/química , Suínos , Resistência à Tração , Adesivos Teciduais/farmacologia , Raios Ultravioleta
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