Papers by Keyword: Albumin

Abstract: Copper and its salt are remarkably non-toxic to mammalian tissue. It is possible to ingest a large number of soluble copper salts such as copper sulphide to produce intoxication, nausea, vomiting, diarrhoea, and abdominal cramp. Copper salts are widely employed in agriculture and veterinary practice. Copper is an essential trace element in life and is a component of several metalloenzymes and other proteins such as cytochrome oxidase, heamocyanin, lysin oxidase, ascorbate oxidase and amine oxidase. When copper is present in the body above a particular dosage of greater than 100ppm in rats, it becomes fatal to rats. Copper is transported by blood, and is distributed to tissue and organs which have different retention capacities with the highest level of copper found in the liver, kidney, spleen and lungs. This study investigated the toxicological effect of copper in the liver and kidney of animals, using albino rats as the experimental animal. The serum chemistry report showed that the protein value of the liver homogenate for most of the experimental rats was higher than that of the control whereas the value of globulin for the control was similar to that of the experimental rats. The kidney homogenate revealed that Calcium ion has higher contents in the experimental rats than that in the control. In conclusion, the effect of copper varies with the groups of rats as compared to the control.

Abstract: Water adsorption in proteins is the crucial process of protein folding and structure stabilizing. Adsorption of water on proteins can be evaluated by near-infrared spectroscopy, a useful technique for observing combination frequency of a water molecule. In this work, albumin, lysozyme, and silk, were used as models for α-helix and β-pleated sheet proteins. Their NIR spectra during water adsorption process were measured by using an NIR spectrometer equipped with a transflectance accessory. Moreover, the quantitative adsorption of water was determined by gravimetric technique. The results indicate that, there are five different NIR absorptions arise from the OH combination frequencies of water adsorbed by albumin in the 5300-5100 cm^-1 region. But there are only four absorptions for lysozyme and silk. The OH combination frequencies arising from water molecules in albumin indicate that it acquires free water molecules (5280 cm^-1) and adsorbed water molecules through carbonyl-water interactions (5248 and 5160 cm^-1) and amino-water interactions (5200 and 5120 cm^-1). Interestingly, there is no indication for the presence of free water molecules in lysozyme and silk. Furthermore, the gravimetric results indicate that the rate of water adsorbed follows the order R_W.Alb<R_W.Lys<R_W.Sil and total mass of water adsorbed per gram solid follows the order W_Alb<W_Lys=W_Sil.

Abstract: In this work, zinc-containing hydroxyapatite (ZnHA) and hydroxyapatite (HA) discs were coated with native bovine serum albumin (BSA) using 100 μg/ml BSA solution at 37°C. Changes on BSA secondary structure from α-helix to β-turn were detected by deconvolution analyses of FTIR amide I band. Fluorescence images of MC3T3-E1 osteoblast cultured on HA and ZnHA discs revealed cells with elongated morphology, typical of 2D experiments, after 24 hours. An intense cytoskeleton organization was observed on samples coated with BSA.

Abstract: Protein adsorption is considered to have a strong influence on the biological reactions of bone-substituting materials. However, the osteoconductivity of protein adsorbed Ti surface is not completely clear. In this study, we produced the protein adsorbed Ti implants using hydro-processing. The hydrothermal treatment in the distilled water gave the super-hydrophilic Ti surface and they had much protein adsorbability. Fibronectin or albumin was picked up as a protein, which was cell adhesive protein and not cell adhesive, respectively. And also, the content of the adsorbed protein was evaluated by FT-IR (ATR) analysis. The water contact angle influenced the amount of the adsorption of the protein and the osteoconductivity of the samples were evaluated by in vivo testing.

Abstract: Magnesium and magnesium alloys are gaining considerable attention for use in biomedical applications due to their capability to completely resorb in the human body without noticeable side effects. For structural biomedical applications however, the resorption rate is too large. In order to decrease this rate researchers are investigating magnesium alloys with an increased corrosion resistance and/or biodegradable coatings, such as dense protein layers, which retard the resorption.In this work, we demonstrate the electrophoretic deposition of Bovine Serum Albumin (BSA) directly onto pure magnesium substrates using unbalanced alternating fields (AC-EPD). The effect of the obtained coatings on the corrosion behavior of the substrates was evaluated by potentiodynamic polarization. The results show that an albumin layer deposited by AC-EPD from a 50/50 ethanol/H₂O medium significantly reduces the corrosion rate.

Abstract: The functional properties of protein isolate and major protein fractions prepared from Changbai Mountain pine nuts were investigated. Albumin, globulin, glutelin, and protein isolates were obtained after the Osborne method and alkaline dissolution and acid precipitation, and protein contents of the fractions are 48.02%, 81.93%, 83.02%, and 89.69%, respectively. For the sulfhydryl contents, albumin is the highest, and glutelin is the lowest. In a disulphide bond, the protein isolate content is the highest with a value of 28.74 μmol/g, and the glutelin content is the lowest with the value of 13.46 μmol/g. For the four kinds of proteins, the essential amino acids in percentage of total amino acids are 31.13%, 34.22%, 30.30%, and 34.54%, respectively. The pH dependent protein solubility profile reveals that the minimum solubility is at pH 5.0, which corresponds to the isoelectric point. Protein isolate has the minimum water absorption capacity with a value of 0.59 ml/g. On the other hand, albumin has the minimum oil absorption capacity with a value of 2.11 ml/g. The emulsifying activity and stability and the foaming activity and stability increased with increasing concentration of four kinds of proteins. SDS-PAGE results showed that these four kinds of proteins have different molecules.

Abstract: Wheat is the most important foodstuff in the world. The proteins in wheat were classified into solubility groups and insolubility. Moreover, the proteins of wheat were divided into four groups, which are glutenin, gliadins, globulins and albumins. The work was according these four characteristic of proteins in wheat to review. This work may provide a useful tool for researching proteins in wheat in the future.

Abstract: MC3T3-E1 cell responses, such as cell adhesion and proliferation, to original and bovine serum albumin (BSA) coated disc (original-disc, BSA-disc) of hydroxyapatite (HA) or alpha-type alumina (α-Al₂O₃) was studied. There was no significant difference in the cell proliferation between BSA-discs and original-discs even after incubated for 14 days, but the cell number at day 14 tended to be higher (p = 0.054) on the BSA-discs of HA than on the original-discs of HA. Incidentally, the amount of adsorbed protein was higher on BSA-discs than on original-discs only until incubated in culture medium for 3 h. BSA adsorption might influence the MC3T3-E1 cell adhesion to HA, as a result the specific adsorption of albumin on HA is likely to affect the expression of the osteoconductivity of materials.

Abstract: Titanium and its alloys are the main metals studied as porous metallic implants by their excellent mechanical properties and biological interactions. Production methods of porous metallic materials are based on powder metallurgy (PM), because it allows the manufacturing of parts with complex shapes and dimensions close to the finals (near-net shape), and the addition of alloying elements reaching a satisfactory structural homogeneity, and porosity. The pore production by space-holder technique constitutes of mixing organic compounds with metal powder, which when removed by thermal treatment prior structures are kept in place. The objective of this study is to obtain porous implants of commercially pure titanium (cpTi) and Ti-13Nb-13Zr alloy by PM with space-holder technique and albumin as an additive. For the processing of the samples were used hydride titanium powder (TiH₂) to obtain cpTi samples, and metal powders of Ti, Nb and Zr in the stoichiometric proportions for obtaining the alloy samples. The samples were prepared by mixing the metallic powder to the albumin (30wt%) and filling a silicone model that was pressed isostatically (140 MPa). The thermal treatment was performed in an oxidizing atmosphere (350°C/1h) for the decomposition of organic material. The sintering was performed at a temperature of 1300°C (1h/cpTi, 3h/Alloy) in high vacuum furnace (10^-5 mBar) to all samples. The calculated porosity showed a significant difference between the samples cpTi (40%) and alloy (60%). The samples surface characterization showed very rough with high specific surface area. Samples of cpTi presented formation of necks arising from sintering. In the alloy samples were observed homogenous microstructure with the presence of α and β phases composing the Widmanstätten structure. It is possible to conclude that the same amount albumin allowed the formation of pores in the microstructure of cpTi and alloy although in different proportions, without harming the sintering of both and allowing diffusion of the alloy elements.

Abstract: Hydroxyapatite nanoparticles were synthesized by preparing an aqueous solution comprising 0.5M Ca(OH)₂, 0.3M H₃PO₄ and 1M CH₃CHCO₂HOH (lactic acid) at pH of 3.7. KOH was added to the solution until pH=12 was reached, to precipitate hydroxyapatite. The incubation time ranged from 24 to 88 hours and the precipitates were then filtered on filter paper with the aid of a vacuum pump. The powders were synthesized with and without PVP addition. The powders were then sintered at 1100°C. Sintered and non sintered powders were characterized by scanning electron microscopy with field emission gun (FEG-SEM) and transmission electron microscopy (TEM) in order to assess particles morphology. Structural characterization was performed by X-ray diffractometry with Rietveld refinement. Albumin adsorption experiments were carried out on the powders with the aid of UV-VIS spectrometry. The results showed that the samples produced in the presence of PVP showed smaller particles when compared to non-dispersed samples. Albumin adsorption was more effective on the powders synthesized with dispersant.