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Cryobiology Dec 2015We describe here a new cryobiological and neurobiological technique, aldehyde-stabilized cryopreservation (ASC), which demonstrates the relevance and utility of advanced...
We describe here a new cryobiological and neurobiological technique, aldehyde-stabilized cryopreservation (ASC), which demonstrates the relevance and utility of advanced cryopreservation science for the neurobiological research community. ASC is a new brain-banking technique designed to facilitate neuroanatomic research such as connectomics research, and has the unique ability to combine stable long term ice-free sample storage with excellent anatomical resolution. To demonstrate the feasibility of ASC, we perfuse-fixed rabbit and pig brains with a glutaraldehyde-based fixative, then slowly perfused increasing concentrations of ethylene glycol over several hours in a manner similar to techniques used for whole organ cryopreservation. Once 65% w/v ethylene glycol was reached, we vitrified brains at -135 °C for indefinite long-term storage. Vitrified brains were rewarmed and the cryoprotectant removed either by perfusion or gradual diffusion from brain slices. We evaluated ASC-processed brains by electron microscopy of multiple regions across the whole brain and by Focused Ion Beam Milling and Scanning Electron Microscopy (FIB-SEM) imaging of selected brain volumes. Preservation was uniformly excellent: processes were easily traceable and synapses were crisp in both species. Aldehyde-stabilized cryopreservation has many advantages over other brain-banking techniques: chemicals are delivered via perfusion, which enables easy scaling to brains of any size; vitrification ensures that the ultrastructure of the brain will not degrade even over very long storage times; and the cryoprotectant can be removed, yielding a perfusable aldehyde-preserved brain which is suitable for a wide variety of brain assays.
Topics: Animals; Brain; Cryopreservation; Cryoprotective Agents; Ethylene Glycol; Glutaral; Rabbits; Swine; Tissue Banks; Vitrification
PubMed: 26408851
DOI: 10.1016/j.cryobiol.2015.09.003 -
The Journal of Thoracic and... Jun 2018
Topics: Aortic Valve; Glutaral; Pericardium
PubMed: 29567132
DOI: 10.1016/j.jtcvs.2018.01.091 -
Circulation Journal : Official Journal... Sep 2018
Topics: Disinfection; Endocarditis; Glutaral; Humans; Mitral Valve
PubMed: 30175803
DOI: 10.1253/circj.CJ-18-0917 -
The Journal of Thoracic and... Jun 2018
Topics: Aortic Valve; Glutaral; Pericardium
PubMed: 29530579
DOI: 10.1016/j.jtcvs.2018.01.075 -
International Journal of Biological... Mar 2022Polysaccharides and proteins are important macromolecules for developing hydrogels devoted to biomedical applications. Chemical hydrogels offer chemical, mechanical, and... (Review)
Review
Polysaccharides and proteins are important macromolecules for developing hydrogels devoted to biomedical applications. Chemical hydrogels offer chemical, mechanical, and dimensional stability than physical hydrogels due to the chemical bonds among the chains mediated by crosslinkers. There are many crosslinkers to synthesize polysaccharides and proteins based on hydrogels. In this review, we revisited the crosslinking reaction mechanisms between synthetic or natural crosslinkers and polysaccharides or proteins. The selected synthetic crosslinkers were glutaraldehyde, carbodiimide, boric acid, sodium trimetaphosphate, N,N'-methylene bisacrylamide, and polycarboxylic acid, whereas the selected natural crosslinkers included transglutaminase, tyrosinase, horseradish peroxidase, laccase, sortase A, genipin, vanillin, tannic acid, and phytic acid. No less important are the reactions involving click chemistry and the macromolecular crosslinkers for polysaccharides and proteins. Literature examples of polysaccharides or proteins crosslinked by the different strategies were presented along with the corresponding highlights. The general mechanism involved in chemical crosslinking mediated by gamma and UV radiation was discussed, with particular attention to materials commonly used in digital light processing. The evaluation of crosslinking efficiency by gravimetric measurements, rheology, and spectroscopic techniques was presented. Finally, we presented the challenges and opportunities to create safe chemical hydrogels for biomedical applications.
Topics: Click Chemistry; Cross-Linking Reagents; Glutaral; Horseradish Peroxidase; Hydrogels; Polysaccharides
PubMed: 35038469
DOI: 10.1016/j.ijbiomac.2022.01.029 -
The Annals of Thoracic Surgery Jun 2013
Topics: Female; Glutaral; Humans; Male; Mitral Valve; Mitral Valve Annuloplasty; Mitral Valve Insufficiency; Pericardium
PubMed: 23706424
DOI: 10.1016/j.athoracsur.2013.04.001 -
Sovremennye Tekhnologii V Meditsine 2021was to assess the cytotoxic effect of xenopericardial biomaterial treated with di- and pentaepoxides on the cell cultures .
UNLABELLED
was to assess the cytotoxic effect of xenopericardial biomaterial treated with di- and pentaepoxides on the cell cultures .
MATERIALS AND METHODS
Samples of bovine and porcine pericardium were used in the work. Three different modes were employed for preservation: 1) 0.625% solution of glutaraldehyde (GA) and a two-fold change on days 2 and 7; 2) 5% solution of ethylene glycol diglycidyl ether (EGDE) changed on day 2; 3) 5% EGDE solution for 10 days, then 2% pentaepoxide solution also for 10 days. The cytotoxicity of the biomaterial was assessed by the extraction method. To determine the cytotoxicity of the biomaterial, EA.hy926 cells, multipotent mesenchymal stem cells (MMSCs), and fibroblasts were used. Cell viability was determined by the MTT test. The level of apoptosis and necrosis in the cell cultures was assessed by staining with acridine orange and ethidium bromide after cultivation with xenopericardial extracts employing different modes of preservation.
RESULTS
Extracts of bovine and porcine pericardium preserved with GA have been found to have the greatest toxic effect on the cell cultures showing 20-33% reduction of cell viability. Extracts from bovine and porcine pericardium preserved with di- and pentaepoxy compounds do not have a toxic effect on endothelial cells, MMSCs, and fibroblasts since cell viability reduction is by no more than 15%. The lowest level of apoptosis and necrosis is observed in the cell cultures under the influence of extracts from the pericardium, preserved with diepoxide and pentaepoxide compounds.
CONCLUSION
According to the MTT test for cytotoxicity and determination of the level of apoptosis and necrosis in cell cultures, bovine and porcine pericardia treated with di- and pentaepoxides have been established to have no cytotoxic effect on the culture of endothelial EA.hy926 cells, MMSCs, fibroblasts , whereas GA, in comparison with di- and pentaepoxides, has a toxic impact on the cells.
Topics: Animals; Biocompatible Materials; Cattle; Cross-Linking Reagents; Endothelial Cells; Glutaral; Pericardium; Swine
PubMed: 34603761
DOI: 10.17691/stm2021.13.4.03 -
International Journal of Biological... Apr 2022Among the matrices for enzyme immobilization, activated carbon has been standing out in immobilization processes due to its properties and to its characteristics that...
Among the matrices for enzyme immobilization, activated carbon has been standing out in immobilization processes due to its properties and to its characteristics that provide superficial modification by inserting new functional groups capable of binding the enzymes forming covalent bonds. In this study the effect of different modification methods of activated carbon (functionalization with genipin, metallization, metallization in the presence of chelating agent, and functionalization with glutaraldehyde) on efficiency of pepsin immobilization was evaluated. The effect of immobilization pH and the reaction medium on hydrolysis activity of bovine casein was also evaluated. The functionalization of activated carbon using iron ions allowed an immobilization capacity of 98.93 mg·g, with immobilization efficiency greater than 99%, and enzyme activity of 2.30 U, which was higher than the other modifications, and closer to the enzyme in the native form activity (3.32 U). In general, the carbon surface modifications were responsible for forming more stable bonds between support and enzyme, improving its proteolytic activity (from 1.84 to 2.30 U) when compared to traditional immobilization methods by adsorption and covalent binding using glutaraldehyde (from 1.04 to 1.1 U).
Topics: Adsorption; Animals; Cattle; Enzyme Stability; Enzymes, Immobilized; Glutaral; Hydrogen-Ion Concentration; Pepsin A
PubMed: 35090943
DOI: 10.1016/j.ijbiomac.2022.01.135 -
Glutaraldehyde-pea protein grafted polysaccharide matrices for functioning as covalent immobilizers.Scientific Reports Jun 2023Three polysaccharide matrices (κ-Carrageenan (Carr), gellan gum, and agar) were grafted via glutaraldehyde (GA) and pea protein (PP). The grafted matrices covalently...
Three polysaccharide matrices (κ-Carrageenan (Carr), gellan gum, and agar) were grafted via glutaraldehyde (GA) and pea protein (PP). The grafted matrices covalently immobilized β-D-galactosidase (β-GL). Nonetheless, grafted Carr acquired the topmost amount of immobilized β-GL (iβ-GL). Thus, its grafting process was honed via Box-Behnken design and was further characterized via FTIR, EDX, and SEM. The optimal GA-PP-Carr grafting comprised processing Carr beads with 10% PP dispersion of pH 1 and 25% GA solution. The optimal GA-PP-Carr beads acquired 11.44 Ug iβ-GL with 45.49% immobilization efficiency. Both free and GA-PP-Carr iβ-GLs manifested their topmost activity at the selfsame temperature and pH. Nonetheless, the β-GL K and V values were reduced following immobilization. The GA-PP-Carr iβ-GL manifested good operational stability. Moreover, its storage stability was incremented where 91.74% activity was offered after 35 storage days. The GA-PP-Carr iβ-GL was utilized to degrade lactose in whey permeate with 81.90% lactose degradation efficiency.
Topics: Enzymes, Immobilized; Glutaral; Pea Proteins; Lactose; Temperature; Carrageenan; Hydrogen-Ion Concentration; Enzyme Stability; beta-Galactosidase
PubMed: 37277367
DOI: 10.1038/s41598-023-36045-z -
Biomolecules Jul 2022In the current study, the purified β-mannanase (Man/Cel5B) from was immobilized on glutaraldehyde cross-linked chitosan beads. The immobilization of Man/Cel5B on...
In the current study, the purified β-mannanase (Man/Cel5B) from was immobilized on glutaraldehyde cross-linked chitosan beads. The immobilization of Man/Cel5B on chitosan beads was confirmed by Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis. After immobilization, the protein loading efficiency and immobilization yield were found to be 73.3% and 71.8%, respectively. The optimum pH for both free and immobilized enzymes was found to be pH 5.5. However, the optimum temperature of immobilized Man/Cel5B increased by 10 °C, from 85 °C (free Man/Cel5B) to 95 °C (Immobilized). The half-life of free and immobilized enzymes was found to be 7 h and 9 h, respectively, at 85 °C owing to the higher thermostability of immobilized Man/Cel5B. The increase in thermostability was also demonstrated by an increase in the energy of deactivation (209 kJmol) for immobilized enzyme compared to its native form (92 kJmol), at 85 °C. Furthermore, the immobilized Man/Cel5B displayed good operational stability as it retained 54% of its original activity after 15 repeated catalytic reactions concerning its free form.
Topics: Chitosan; Enzyme Stability; Enzymes, Immobilized; Glutaral; Humans; Hydrogen-Ion Concentration; Kinetics; Temperature; beta-Mannosidase
PubMed: 35883557
DOI: 10.3390/biom12070999