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101.
Tanabe S Kobayashi Y Takahata Y Morimatsu F Shibata R Nishimura T 《Biochemical and biophysical research communications》2002,293(5):1348-1353
Bovine serum albumin (BSA) is the major beef allergen. Since IgE and T cell recognitions are central to the specific immune response to allergens, the identification and immunologic characterization of B and T cell epitopes of BSA represent important steps in the development of treatments for beef allergy. Prior to our experiments, we hypothesized that BSA-specific antibodies and T cells react primarily with sequential epitopes in which the amino acid sequences differ greatly between bovine and human albumin. To clarify this hypothesis, 16 peptides corresponding to such regions were synthesized as candidate epitopes. Among them, at least two regions, aa336-345 and aa451-459, were found to be B cell (IgE-binding) epitopes. In inhibition ELISA experiments, EYAV (aa338-341) and LILNR (aa453-457) bound to patient IgE antibodies and were found to be the cores of the IgE-binding epitopes. Three regions, DDSPDLPKLKPDPNTLC (aa107-123), PHACYTSVFDKLKHLVDEP (aa364-382), and LSLILNRLC (aa451-459), were found to induce T cell proliferation in more than half of the patients tested. Of interest was that these three regions were also recognized by B cells. Information concerning human B and T cells epitopes can contribute greatly to the elucidation of the etiology of beef allergy. 相似文献
102.
Stereological methods were applied to bovine cumulus-oocyte complexes (COCs) in order to characterize them quantitatively during the estrous cycle. COCs from medium (4-8mm) antral follicles with a compact and complete cumulus mass, and with an uniform or a non-visible ooplasm were aspirated from ovaries of Holstein-Friesian cows, fixed in glutaraldehyde, randomly embedded in glycol-methacrylate, and sectioned at 20 microm. The unbiased nucleator principle was used for estimating the mean volumes of complexes, oocytes, cumulus cells, and nuclei of oocytes and cumulus cells. The thickness of the zona pellucida and the relative numerical percentages of the several morphological types (C1-C3) of cumulus cells were also evaluated. The optical disector procedure was used for cumulus cell sampling. Quantitative data show that COCs appear heterogeneous for all studied parameters. From metestrus to proestrus the volumes of COCs and oocytes remained constant, the volumes of oocytes and oocyte nuclei were correlated, the thickness of the outer zona pellucida decreased, and the relative numerical frequency of follicular type C3 cells increased. Results suggest that COCs from distinct estrus stages are structurally different, with type C3 follicular cells gradually differentiating from cell types C1 and C2. 相似文献
103.
A solid phase adsorption method was proposed to prepare well-defined bovine serum albumin–bovine hemoglobin (Hb) conjugate. After adsorption by the solid phase, Q Sepharose Fast Flow media, bovine serum albumin (BSA) molecules were allowed to react with glutaraldehyde. The spacing out of BSA molecules on the solid phase was assumed to limit polymerization of BSA molecules, except some molecules bound closely on the solid phase resulting in minor dimer formation. Following the elution procedure, the activated monomeric BSA was separated from the dimers by gel filtration chromatography on Superdex 200 and then reacted with bovine Hb at 4 °C and pH 9.5. The 1:1 (BSA:Hb) conjugate was obtained with the yield of 64%. The P50 values of the conjugates, prepared under anaerobic and aerobic conditions, were 19.1 and 14.2 mmHg, respectively. The dependence of the P50 on chloride ions for the conjugate was slightly diminished, presumably due to covalent attachment of BSA to bovine Hb. 相似文献
104.
Cytochrome c oxidase, Cu,Zn-superoxide dismutase, and ceruloplasmin activities in copper-deficient bovines 总被引:1,自引:0,他引:1
Cerone SI Sansinanea AS Streitenberger SA Garcia MC Auza NJ 《Biological trace element research》2000,73(3):269-278
The activity of several cuproenzymes in relation to the immune system was examined in serum and blood cells from bovines with
molybdenum-induced copper deficiency. Five female cattle were given molybdenum (30 ppm) and sulfate (225 ppm) to induce experimental
secondary copper deficiency. Ceruloplasmin activity was determined in serum. The Cu,Zn-superoxide dismutase and cytochrome
c oxidase activities were measured in peripheral blood lymphocytes, neutrophils, and monocyte-derived macrophages. Copper deficiency
was confirmed from decreased serum copper levels and the animals with values less than 5.6 μmol/L were considered deficient.
The content of intracellular copper decreased between 40% and 70% in deficient cells compared with the controls. In copper-deficient
animals, the serum ceruloplasmin activity decreased to half of the control value. Both of them, the Cu,Zn-superoxide dismutase
and the cytochrome c oxidase activities, undergo a significant reduction in leukocytes, showing differences among diverse cell populations. We
concluded that the copper deficiency alters the activity of several enzymes, which mediate antioxidant defenses and ATP formation.
These effects may impair the cell immune functionality, affecting the bactericidal capacity and making the animals more susceptible
to infection. 相似文献
105.
Light scattering measurements were performed on dilute solutions of α-crystallin mixed with different combinations of βH, βL and γ-fractions of bovine lens crystallins. Light scattering intensities were obtained as a function of scattering angle, concentration and temperature. The temperature dependence of the second virial coefficients was used to obtain partial molar enthalpy and end entropy of solutions. The difference between the thermodynamic parameters of the crystallin mixtures and those of the weighted averages of the individual components yielded the excess enthalpy and entropy functions of the solutions. Both the excess enthalpy and entropy functions indicated that thermodynamic stability of α-crystallin is progressively enhanced by its interactions with γ(βH+γ)(βH+βL+γ) crystallins. The last two combinations showed negative values both for excess enthalpy as well for excess entropy of solutions. Other combinations demonstrated increasing positive values. This implies that the combination of all four crystallins in the vertebrate lens enables the best solvation property as well as the best packing as opposed to any other single or combinatorial arrangements of crystallins. Similar conclusions have been obtained in the past from water and other vapor sorption studies. 相似文献
106.
A system of capillary silica monolith with bovine serum albumin (BSA) functionalized through two approaches for affinity monolithic capillary electrochromatography (AMCEC) was developed. Covalent immobilization conditions for two different Schiff base methods, which employed 3-glycidopropyl trimethoxysilane (GPTS) and 3-aminopropyl trimethoxysilane (APTS) as starting materials, respectively, were investigated to obtain good and stable chiral separation. The BSA immobilized silica monoliths were evaluated in terms of morphology, electroosmotic flow, retention time, column efficiency and resolution of model compound (±)-tryptophan. The columns exhibited satisfactory run-to-run, column-to-column repeatability and maintained their enantioselectivity for more than 3 months. Both developed methods can baseline separate tryptophan enantiomers, whereas shorter retention time, better column efficiency, and enantiomeric recognition between two pairs of drug enantiomers (pantoprazole and atenolol) were obtained by the GPTS method. 相似文献
107.
One approach to treating the dengue virus infection is to inhibit its NS2B-NS3 protease that plays a vital role in virus maturation. However, the lack of structural information on the active conformation of the protease hindered related drug design. With a co-expression system, we obtained the active two-component protease in its unlinked form. BPTI shows strong competitive inhibitory activity (Ki = 6.5 nM) against this unlinked protease, which adopts a closed conformation. Based on the biochemical and NMR perturbation information, an inhibition model of BPTI to NS2B-NS3 protease is proposed. 相似文献
108.
Influence of various antioxidants added to TCM-199 on post-thaw bovine sperm parameters,DNA integrity and fertilizing ability 总被引:1,自引:0,他引:1
Serpil Sarıözkan Mustafa Numan Bucak Pürhan B. Tuncer Serhat Büyükleblebici Fazile Cantürk 《Cryobiology》2014
Supplementation of the semen extender with antioxidants did not produce any significant effect on CASA and progressive motilities and sperm motility characteristics, in comparison to the control group (P > 0.05). 相似文献
109.
Vicky P. K. H. Nguyen George Hanna Natalie Rodrigues Katerina Pizzuto Eric Yang Paul Van Slyke Harold Kim Stephen H. Chen Daniel J. Dumont 《Proteomics》2010,10(8):1658-1672
Differential protein profiling by 2‐D PAGE is generally useful in biomarker discovery, proteome analysis and routine sample preparation prior to analysis by MS. The goal of this study was to compare 2‐D PAGE‐resolved protein profile of lymphatic endothelial cells to those of venous, and arterial endothelial cells isolated from lymphatic and blood vessels of bovine mesentery (bm). Three 2‐D PAGE electrophoretograms were produced for each of the three cell types and quantitatively analyzed. Protein identification by LC‐MS/MS was performed to identify 39 proteins found to be present at statistically significantly different levels in the three cell types (p<0.05). Most of the 39 proteins have not been previously reported in EC proteomic studies of 2‐D PAGE electrophoretograms. Three proteins, HSPA1B (HSP70 family member), HSPB1 (HSP27 family member), and UBE2D3 (a member of E2 ubiquitin‐conjugating enzymes) found to be at highest levels in bm arterial endothelial cells, bm venous endothelial cells, and bm lymphatic endothelial cells, respectively, were validated by immunoblotting with appropriate antibodies. The lack of substantial overlap between our results and those of other groups' comparative studies are discussed. Functional implications of differences in levels of various proteins identified in the three cell types are also discussed. 相似文献
110.