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1.
BACKGROUND: Soy lecithin and soy oil are usually produced from the hexane extract of soybean. Some of the soybean proteins are included in the extract and are therefore present in small amounts in both soy lecithin and soy oil. The antigenicity of the proteins present in defatted soybean has been studied with respect to soybean allergy, but the antigenicity of those found in the extract is yet to be investigated. OBJECTIVE: The antigenicity of soy lecithin and soy oil proteins with regard to soybean allergy were investigated. METHODS: The proteins present in soy lecithin and soy oil were determined according to already established method and analysed by SDS-PAGE. The IgE- and IgG4-binding abilities of the soy lecithin proteins were investigated by immunoblotting with sera from 30 soybean-sensitive patients, including seven with a positive challenge test. Immunoblotting of soy oil proteins was performed with the sera from some of these patients. RESULTS: In 100 g of sample, the soy lecithin and soy oil contained 2.8 mg and 1.4-4.0 microg of proteins, respectively. The results of SDS-PAGE demonstrated the presence of only three proteins, with molecular weights of about 58-67 kDa in soy oil, and suggested that soy lecithin also contains these proteins. The soy lecithin also contained many proteins besides these. In the soy lecithin, the detection rate of only one protein, with a molecular weight of 31 kDa, by the serum IgE of patients was significantly different compared with controls (detection rate: 40%). The proteins with molecular weights of 58-67 kDa rarely bound to serum IgE. Only one of the patients who presented a positive challenge test had IgE antibodies to soy lecithin proteins. IgG4-binding proteins were found only rarely in soy lecithin. Neither the IgE nor the IgG4 present in the patients' sera reacted to any soy oil protein. CONCLUSION: Proteins present in soy lecithin and soy oil have little antigenicity with regard to soybean allergy.  相似文献   

2.
Gong T  Li W  Chen H  Wang L  Shao S  Zhou S 《Acta biomaterialia》2012,8(3):1248-1259
One class of biodegradable polymer composite nanofibers was fabricated with an electrospinning process using chemically cross-linked poly(ε-caprolactone) (c-PCL) as the matrix and multiwalled carbon nanotubes (MWNTs) as the reinforced filler coated with Fe(3)O(4) nanoparticles as a magnetism responsive source. The composite fibers showed an excellent shape memory effect, triggered both by hot water and by an alternating magnetic field. The heat in the PCL matrix generated from magnetic nanoparticles via hysteresis loss in the magnetic field was also determined quantitatively. The Fe(3)O(4)-loaded MWNT composite nanoparticles (Fe(3)O(4)@CD-M) were synthesized through two steps: (1) the raw MWNTs were firstly functionalized by grafting maleic anhydride (MA) on their surface through a free radical reaction and later covalently modified by β-cyclodextrin (β-CD) through an esterification reaction; (2) Fe(3)O(4)@CD-M composite nanoparticles were prepared by chemical co-precipitation of Fe(2+) and Fe(3+) ions on the surface of the β-CD functionalized MWNTs with an electrostatic self-assembly approach using β-CD as the depositional locus. Alamar blue assay was also performed from culturing osteoblast populations to evaluate the cytotoxicity. The result showed that the electrospun composite fibers possessed good biocompatibility and could be applied in biomedical fields.  相似文献   

3.
Previously, we developed a novel alternate soaking process and clarified that bone-like apatite was formed on/in organic polymer hydrogel matrices using this process. The present study focused on the apatite coating on hydrophilic polymer grafted poly(ethylene) (PE) films with various grafting densities and commonly used hydrophilic polymers, poly(acryl amide) (PAAm) and poly(acrylic acid) (PAAc) were employed. From X-ray diffraction analysis, hydroxyapatite was coated on PAAm- or PAAc- grafted PE films. The amount of apatite coated on PAAm-grafted PE (PAAm-g-PE) films increased with an increase in the reaction cycles and the grafting density of PAAm. Similar to PAAm-g-PE, the amount of apatite coated on PAAc-grafted PE (PAAc-g-PE) films increased linearly with an increase in the grafting density of the PAAc up to around 30 microg/cm2. While, no significant increase in the apatite coating on the PAAc-g-PE films was observed even after 50 reaction cycles when the grafting densities of PAAc were over 30 microg/cm2. Apatite coating was not observed on original PE films. Scanning electron microscopic images reveal that the aggregation of apatite crystals on all PAAm-g-PE films and PAAc-g-PE films with grafting density from 10 to 30 microg/cm2. On the other hand, a dense apatite layer with some cracks was coated when the grafting density of the PAAc chains was over 30 microg/cm2. These results indicated that it was possible to coat apatite on hydrophilic polymer grafted PE films by an alternate soaking process and that the apatite crystal morphology could be controlled as a function of polymer type and density.  相似文献   

4.
The fabrication of apatite-organic polymer hybrids is one of several attractive methods for the development of biomaterials as a substitute for bone. Such materials have both bone-bonding ability and mechanical properties analogous to natural bone. The biomimetic process has focused attention on fabricating such hybrids, where bone-like apatite is deposited on an organic polymer surface in solutions that mimic physiological conditions. In this process, a bone-like apatite layer can be coated onto organic substrates either by using a simulated body fluid (SBF) with ion concentrations nearly equal to those of human extracellular fluid, or by using fluids that are supersaturated with respect to apatite at ambient conditions. In this study, we investigated the ability of natural silk and its related materials to facilitate apatite deposition under biomimetic conditions. Cloths made of raw silk or normal silk fibers were soaked in 1.5SBF, which has 1.5 times the ion concentration of SBF. Sericin film, which is made from an extract of degummed raw silk, was soaked in 1.5SBF. The cloth and the film soaked in 1.5SBF then were characterized by scanning electron microscopic (SEM) observation, energy dispersive X-ray microanalysis (EDX), and thin-film X-ray diffraction (TF-XRD). Apatite deposition was observed on the surface of cloth made from raw silk fiber after it was soaked in 1.5SBF, but it was not observed on cloth made from normal silk fibers. The apatite deposition on the raw silk fiber cloth was accelerated when the fibers were subjected to treatment with CaCl(2) solution at a concentration of at least 1 kmol/m(3) before immersion in 1.5SBF. Apatite deposition also was observed on the sericin film after the film was soaked in 1.5SBF for 7 days. These results indicate that apatite deposition on raw silk cloth is attributable to the catalytic effect of sericin because the surface of raw silk consists of sericin whereas that of normal silk contains fibroin. The deposition of the apatite and its crystal growth are accelerated by the presence of calcium ions on the sericin after treatment with CaCl(2) solution. Thus, sericin on natural silk fiber has the potential to facilitate apatite deposition and can be useful as a polymer material in the fabrication of hybrid materials analogous to bone through biomimetic processes.  相似文献   

5.
Acrylic (polymethylmethacrylate or PMMA) bone cement was modified by the addition of high-strength zirconia fibers with average lengths of 200 microm and diameters of 15 microm or 30 microm. A novel emulsion polymerization process was developed to encapsulate individual fibers in PMMA. Improvements in tensile and compressive properties as well as in fracture toughness were investigated upon incorporation of uncoated and acrylic coated zirconia fibers. Bone cements were reinforced with 2% by volume of the 15 microm diameter and 5% by volume of the 30 microm fibers. Results indicate that elastic modulus and ultimate strength of bone cements reinforced with zirconia fibers were higher than controls, being the largest for cements reinforced with 30 microm diameter fibers. The fracture toughness of the cement increased by 23% and 41% by the addition of 15 microm and 30 microm fibers, respectively. Coating of individual zirconia fibers did not result in improved material properties of bone cements. The use of uncoated or acrylic coated 30 microm fibers is recommended based on the significant increases in ultimate strength and fracture toughness of the cements.  相似文献   

6.
The capacity of selective uptake by liver cells, focusing particularly on the parenchymal and perisinusoidal stellate cells during chick liver development (8–18 days of incubation), was ultrastructurally examined after injection of 240‐nm‐diameter lecithin (phosphatidylcholine) ‐coated or noncoated beads into the extraembryonic circulation. Cytoplasmic projections of both cells as well as extrasinusoidal macrophages reached into the sinusoid‐like vascular spaces. The primitive perisinusoidal stellate cells were identified by immunocytochemistry as being rich in desmin‐positive cytoplasmic intermediate filaments. The cells demonstrated selective uptake of noncoated beads by means of their cytoplasmic projections. These findings were significant in the early period of incubation, indicating that the phagocytic activity is a characteristic and transient phenomenon of developmental differentiation. Large numbers of coated and a few noncoated beads penetrated into the perivascular spaces. The parenchymal cells incorporated only the coated beads that passed through the endothelial lining, suggesting that these cells express selective but limited phagocytic capacity against large “foreign” substances even long before their maturation. The cell projections were not engaged in uptake function. Extrasinusoidal macrophages, Kupffer cells, and intraluminal primitive macrophages all took up both beads; however, lecithin coating of the beads clearly suppressed their uptake function. These data suggest that the uptake function of large “foreign” substances appears to be intrinsic to liver cells and lecithin coating would be useful for delivering large substances to parenchymal cells. Anat Rec, 2007. © 2007 Wiley‐Liss, Inc.  相似文献   

7.
Dacron vascular prostheses were examined under both light and electron microscopes from 1 to 1184 days after implantation in the thoracic aorta of 96 dogs. Each Dacron fiber of the implanted prostheses was found to be covered with a single layer, which closely resembled the outer half leaflet of plasma membrane. The control experiment in vitro revealed that when untreated Dacron fibers were dipped into a solution of lecithin, the fibers became covered with monomolecular leaflets of lecithin micelles. On the basis of the in vivo and in vitro findings, it was suggested that the implanted Dacron fibers of vascular prosthesis were covered at an early stage with a monomolecular micelle layer of phospholipid or phospholipoproteins originating from the living body, and thus became adapted to the living body.  相似文献   

8.
目的研究大豆卵磷脂调节血脂的作用。方法将动物随机分为空白对照组、高脂模型对照组和大豆卵磷脂低、中、高三个剂量组,剂量组每天灌胃给予样品,并同时喂饲高脂饲料。于给样30d后。取血分别测定血清总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白(HDL-c)等指标。结果大豆卵磷脂三个剂量组的TC、TG水平均较高脂模型对照组降低,差异有统计学意义(P〈0.01或P〈0.05)。结论大豆卵磷脂具有调节血脂作用。  相似文献   

9.
Aging is associated with a decline in skeletal muscle function. Previous research suggests that this decline in skeletal muscle function may, in part, be explained by an age-associated decline in the ability of skeletal muscle to reinnervate and/or age-associated changes in fiber types and distribution during reinnervation. This study used a nerve-repair graft model to investigate age-associated changes in the ability to reinnervate via expression of neural cell adhesion molecule (NCAM), a marker of denervated and recently reinnervated muscle fibers and changes in fiber type and Type I fiber grouping in medial gastrocnemius (MG) muscles of 6-, 12- and 24-month-old male Fischer 344 rats. Age had no effect on total MG muscle fiber number. Aging and nerve-repair grafting led to an increase in percent Type I and a decrease in percent Type IIB fibers. Aging and nerve-repair grafting led to an increase in NCAM positive fibers and an increase in the percentage of enclosed Type I muscle fibers, which was greatest in the 24 month nerve-repair grafted group. Thus, we conclude that diminished contractile function of aged and/or nerve-repair grafted MG muscle may be explained, in part, by an increase in the percentage of denervated fibers.  相似文献   

10.
After spinal cord injury, the severed neuronal pathways fail to regenerate spontaneously. This study describes a biodegradable implant using poly-beta-hydroxybutyrate (PHB) fibers as carrier scaffold for matrix components and cell lines supporting neuronal survival and regeneration after spinal cord injury. After cervical spinal cord injury in adult rats, a graft consisting of PHB fibers coated with alginate hydrogel + fibronectin was implanted in the lesion cavity. In control groups, PHB was omitted and only alginate hydrogel or fibronectin, or their combination, were used for grafting. In addition, comparisons were made with animals treated intrathecally after spinal cord injury with the neurotrophic factors BDNF or NT-3. The neurons of the rubrospinal tract served as experimental model. In untreated animals, 45% of the injured rubrospinal neurons were lost at 8 weeks postoperatively. Implantation of the PHB graft reduced this cell loss by 50%, a rescuing effect similar to that obtained after treatment with BDNF or NT-3. In the absence of PHB support, implants of only alginate hydrogel or fibronectin, or their combination, had no effect on neuronal survival. After addition of neonatal Schwann cells to the PHB graft, regenerating axons were seen to enter the graft from both ends and to extend along its entire length. These results show that implants using PHB as carrier scaffold and containing alginate hydrogel, fibronectin and Schwann cells can support neuronal survival and regeneration after spinal cord injury  相似文献   

11.
We report two cases of soybean-lecithin-induced asthma in bakers. The patients experienced clinical symptoms in relation to an occupational exposure to this additive. Skin tests were positive with soybean lecithin, RAST showed a sensitization to soybean, and bronchial challenge tests were positive for a dilution of 10-3 with this allergen. The same tests remained negative among healthy and asthmatic controls. Soybean lecithin, a common additive in bakery, must be added to the list of numerous aeroallergens involved in baker's asthma.  相似文献   

12.
The use of short glass fibers as a filler for dental restorations or cement resins have not been examined extensively. The mechanical properties and untreated glass fibers (5 microns dia x 25 microns) in Bis-phenol A glycidyl methacrylate (BIS-GMA) diluted with triethylene-glycol dimethacrylate (TEGDMA) resin were investigated for possible use as a restorative dental composite or bone cement. Compression, uniaxial tension and fracture toughness tests were conducted for each filler composite mixtures of 40, 50, 60 and 70%. Set time and maximum temperature of polymerization were determined. The results show that the elastic modulus, tensile strength and compressive strength are dependent on the percent of filler content. Elastic modulus and compressive yield (0.2%) strength of silane treated glass fibers filled composite increased from 2.26 to 4.59 GPa and 43.3 to 66.6 MPa, respectively, wtih increasing the filler content while the tensile strength decreased from 26.7 to 18.6 MPa. The elastic modulus of the untreated composite was less than that of the silane treated fiber composite. The tensile strength and compressive strengths were 20 to 50% lower than those of silane treated composites. The fracture toughness of the silane treated glass fiber additions were not significantly different from the untreated additions. The highest fracture toughness was obtained at 50% filler content with 1.65 MPa m.5. Set time increased from 3.5 to 7.7 minutes with increased filler content and peak temperature dropped from 68.3 to 34 degrees C. The results of this study indicate that the addition of silane coated glass fiber to BIS-GMA resin increased the elastic modulus, tensile and compressive strengths compared with non-treated fibers. The addition of either treated or non-treated fibers increased the set time of the material and decreased the maximum temperature.  相似文献   

13.
The complex interactions that occur between oligodendrocytes and axons during the process of central nervous system myelination and remyelination remain unclear. Elucidation of the cell-biological and -biochemical mechanisms supporting myelin production and elaboration requires a robust in vitro system that recapitulates the relationship between axons and oligodendrocytes in a manner that is open to molecular dissection. We provide evidence for an artificial axon culture system in which we observed oligodendrocytes extending large plasma membrane projections that frequently completely ensheathed fibers coated with a variety of extracellular matrix molecules. These membrane projections varied in extent and thickness depending upon the substrate and upon the diameter of the coated fiber. Matrigel-coated glass microfibers were found to support the development of thick membrane sheaths that extended for hundreds of microns and exhibited many features suggestive of the potential for true myelin deposition. Likewise, Matrigel-coated Vicryl fibers supported plasma membrane extensions that covered extremely large surface areas and occasionally wrapped the coated Vicryl fibers in more than one membrane layer. Our findings suggest that the deposition of molecular cues onto glass or polymer fibers either via adsorption or chemical modification may be a useful tool for the discovery or validation of axonal factors critical for myelination and remyelination. Herein, we provide evidence that polyglactin 910 and glass microfibers coated with adhesion factors may provide a reasonable system for the in vitro analysis of myelination, and may eventually serve a role in engineering artificial systems for neural repair.  相似文献   

14.
Polymers prepared from polylactic acid (PLA) have found a multitude of uses as medical devices. The main advantage of having a material that degrades is so that an implant would not necessitate a second surgical event for removal. In addition, the biodegradation may offer other advantages. In this study, fibers produced from a quaternary phosphate-based glass (PBG) in the system 50P(2)O(5)-40CaO-5Na(2)O-5Fe(2)O(3) (nontreated and heat-treated) were used to reinforce the biodegradable polymer, PLA. Fiber properties were investigated, along with the mechanical and degradation properties and cytocompatibility of the composites produced. Retention of mechanical properties overtime was also evaluated. The mean fiber strength for the phosphate glass fibers was 456 MPa with a modulus value of 51.5 GPa. Weibull analysis revealed a shape and scale parameter value of 3.37 and 508, respectively. The flexural strength of the composites matched that for cortical bone; however, the modulus values were lower than those required for cortical bone. After 6 weeks of degradation in deionized water, 50% of the strength values obtained was maintained. The composite degradation properties revealed a 14% mass loss for the nontreated and a 10% mass loss for the heat-treated fiber composites. It was also seen that by heat-treating the fibers, chemical and physical degradation occurred much slower. The pH profiles also revealed that nontreated fibers degraded quicker, thus correlating well with the degradation profiles. The in vitro cell culture experiments revealed both PLA (alone) and the heat-treated fiber composites maintained higher cell viability as compared to the nontreated fiber composites. This was attributed to the slower degradation release profiles of the heat-treated composites as compared to the nontreated fiber composites. SEM analyses revealed a porous structure after degradation, and it is clear that there are possibilities here to tailor the distribution of porosity within polymer matrices.  相似文献   

15.
In the present study refined and non-refined soybean oils as well as soy lecithins were investigated for residual allergenicity and compared with extracts from native soybeans. By means of immunoblotting and EAST inhibition experiments no IgE-binding activity was detectable in refined soybean oils, which is probably due to thermal treatment during the refining. The investigated non-refined oils and soy lecithins showed a residual IgE-binding activity. In addition in the lecithin extracts a new IgE-binding structure with a molecular mass of approximately 16 kDa was detectable.  相似文献   

16.
Tissue engineering represents a potential method for repairing damaged skeletal muscle tissue. Extracellular matrix (ECM) proteins were evaluated for their ability to aid in cell attachment, whereas a poly(L-lactic acid) (PLLA) fiber scaffold was tested as a substrate for the differentiation of human skeletal muscle cells. In comparison to uncoated or gelatin-coated PLLA films, cell attachment increased significantly (p < 0.001) on PLLA films coated with ECM gel, fibronectin, or laminin. Myoblasts differentiated into multinucleated myofibers on ECM gel-coated PLLA fibers, and expressed muscle markers such as myosin and alpha-actinin. Oligonucleotide microarray analysis showed similar gene expression profiles for human skeletal muscle cells on ECM gel-coated PLLA fibers as to that observed for myofibers on tissue culture plates. Therefore, PLLA fibers coated with ECM proteins provide a scaffold for the development of skeletal muscle tissue for tissue engineering and cell transplantation applications.  相似文献   

17.
During root canal or periodontal treatment, directing laser energy onto the walls of the root canal is essential for effective disinfection. This study assessed the performance of four different fiber modifications that have increased lateral emission, including three designs with safe tips to reduce irradiation directed toward the root apex. Free-running pulsed infrared lasers (Nd:YAG, Er:YAG, and Er,Cr:YSGG) and a diode laser (980 nm) were used in combination with plain ended (forward emitting) laser fibers; conical laser fibers, side firing honeycomb pattern fibers without a safe end; honeycomb fibers with silver coated ends, conical fibers with selectively abraded tips, and selectively abraded honeycomb fibers with silver coated tips (20 fibers for each laser type). Laser emissions forward and laterally were measured, and digital photographs and thermally sensitive paper used to record the emission profiles. Thermochromic dyes painted onto the root surface of an extracted tooth were used to explore the distribution of laser energy with different tips designs. All three safe tipped ends gave reduced emissions in the forward direction (range 17-59%), but had similar lateral emission characteristics. Fiber designs with reduced forward emission may be useful for various dental laser procedures.  相似文献   

18.
Identification of IgE-binding proteins in soy lecithin.   总被引:2,自引:0,他引:2  
BACKGROUND: Soy lecithin is widely used as an emulsifier in processed foods, pharmaceuticals and cosmetics. Soy lecithin is composed principally of phospholipids; however, it has also been shown to contain IgE-binding proteins, albeit at a low level. A few clinical cases involving allergic reactions to soy lecithin have been reported. The purpose of this investigation is to better characterize the IgE-binding proteins typically found in lecithin. METHODS: Soy lecithin proteins were isolated following solvent extraction of lipid components and then separated on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The separated lecithin proteins were immunoblotted with sera from soy-sensitive individuals to determine the pattern of IgE-binding proteins. The identity of IgE-reactive bands was determined from their N-terminal sequence. RESULTS: The level of protein in six lecithin samples obtained from commercial suppliers ranged from 100 to 1,400 ppm. Lecithin samples showed similar protein patterns when examined by SDS-PAGE. Immunoblotting with sera from soy-sensitive individuals showed IgE binding to bands corresponding to 7, 12, 20, 39 and 57 kD. N-terminal analysis of these IgE-binding bands resulted in sequences for 3 components. The 12-kD band was identified as a methionine-rich protein (MRP) and a member of the 2S albumin class of soy proteins. The 20-kD band was found to be soybean Kunitz trypsin inhibitor. The 39-kD band was matched to a soy protein with unknown function. CONCLUSIONS: Soy lecithin contains a number of IgE-binding proteins; thus, it might represent a source of hidden allergens. These allergens are a more significant concern for soy-allergic individuals consuming lecithin products as a health supplement. In addition, the MRP and the 39-kD protein identified in this study represent newly identified IgE-binding proteins.  相似文献   

19.
This study takes place in the field of development of a bioactive surface of titanium alloys. In this paper, titanium was functionalized with cyclo-DfKRG peptide by coating or grafting using different anchors (thiol or phosphonate) as spacers between the surface and the peptide. Cell adhesion, and differentiation of human osteoprogenitor (HOP) cells arising from human bone marrow were investigated. Our results seem to demonstrate that cyclo-DfKRG peptide coating with a phosphonate anchor and grafting procedure contributes to higher cell adhesion and a strong ALP and Cbfa1 mRNA expression, after 10 days of cell seeding. At the contrary, this peptide coated with a thiol anchor stimulates differentiation of HOP within 3 days of culture.  相似文献   

20.
The orthopedic infection, such as osteomyelitis, especially those caused by Methicillin-resistant Staphylococcus aureus (MRSA), remains a major complication of open fractures. Local vancomycin delivery is considered to provide better methods when avascular zones prevent the delivery of drugs from conventional routes of administration. Chitosan (CS) delivery system has been developed with the disadvantages, such as mechanically weakness, lacking osteoconductivity, and the initial burst of antibiotics into the environment. The aim of this study was to confirm that the prepared CS/β-tricalcium phosphate (β-TCP) composites coated with poly (ε-caprolactone) (PCL), similar to natural bone in components, had a three-dimensional porous structure and could be used as drug carriers to deliver vancomycin in a sustained and controlled manner effectively for 6 weeks at levels to inhibit MRSA proliferation. We prepared porous CS/β-TCP composites by incorporating β-TCP into the system, and coated the composites with PCL of three different concentrations. The morphological structure of composites, including pore size and porosity, was examined. The result showed that CS/β-TCP coated with 2.5w/v% PCL solution had the best coating effect and it retarded the release of vancomycin in a near zero-order mechanism from 0 to 14 days. The drug delivery was significantly delayed after coated with 2.5w/v% PCL. The quantitative release of vancomycin was extended to 42 days. Therefore PCL coating could be used to retard the release of vancomycin from CS/β-TCP composites in a sustained and controlled manner. Porous CS/β-TCP coated with PCL might be one of the candidate vancomycin carriers for treating MRSA-related osteomyelitis. ? 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2012.  相似文献   

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