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71.
R Liljequist A Haapalinna M Ahlander YH Li PT M?nnist? 《Canadian Metallurgical Quarterly》1997,82(2):195-202
DNA-based immunization is a promising new technique for generating antibodies in laboratory animals for diagnostic purposes in biological science. The main advantages are the elimination of time and labor and the technically demanding steps of antigen purification. The DNA sequence of the protein of interest, cloned in a suitable in vivo expression vector that is administered intramuscularly or intradermally, is sufficient to induce an immune response in animals. We report the induction of antibodies to tobacco mosaic virus (TMV) coat protein (CP) as a highly immunogenic structural protein and potato virus Y (PVY) P1 protein (P1) as a nonstructural protein. The appropriate nucleotide sequences were introduced in a mammalian expression vector (pSG5) and injected intramuscularly into New Zealand White rabbits (Oryctolagus cuniculus). By 10 days post-injection (dpi) a specific immune response was detected against TMV-CP, while it took about 5 weeks for a response to PVY P1. In both cases the antibody titers were significantly above the corresponding pre-immune serum, however, they were considerably below the titer of the matching conventionally produced antiserum. To our knowledge, this is the first report of DNA-based immunization in order to generate antibodies to plant viral proteins, but further improvements are necessary to increase antibody titers before this promising new technique can be introduced broadly in plant science for diagnostic purposes. 相似文献
72.
73.
Robert L. Wolff Frédérique Pédrono Anne M. Marpeau William W. Christie Frank D. Gunstone 《Journal of the American Oil Chemists' Society》1998,75(11):1637-1641
The fatty acid compositions of the seeds from three Taxus (yew) species and one Torreya species belonging to the Taxaceae family [Taxus cuspidata (Japanese yew), T. chinensis (Chinese yew), T. baccata (English yew), and Torreya grandis (Chinese nutmeg yew)] have been established. These compositions were compared with those previously published for T. canadensis (Canadian yew) and Torreya nucifera. In Taxus species, as well as in Torreya species, Δ5-olefinic acids are present in the seed lipids from all species analyzed. In Taxus, 5,9-18:2 (taxoleic) acid is the prominent Δ5-olefinic acid. It represents between 9.5 and 16.2% of total fatty acids. Other
Δ5-olefinic acids that occur in low amounts are 5,9,12-18:3 (<3.5%), 5,11-20:2 (<0.3%), 5,11,14-20:3 (<2.2%), and 5,11,14,17-20:4
(<0.3%) acids. In Torreya species, the major Δ5-olefinic acid is 5,11,14-20:3 (sciadonic) acid (between 6.7 and 11.2%). In contrast to Taxus species, the 5,9-18:2 and 5,9,12-18:3 acids are scarce in Torreya species: less than 0.1%. Also, the 9,12,15-18:3 acid content is significantly lower in Torreya than in Taxus. The prominence of taxoleic acid among Δ5-olefinic acids in the seed lipids is a unique characteristic of the genus Taxus that isolates it from all other Coniferophytes analyzed so far. However, this feature is not shared by other Taxaceae species,
such as Torreya, and with regard to their seed fatty acid compositions, the family Taxaceae appears particularly heterogeneous. Our observations
favor the hypothesis that in Gymnosperm seeds, there might exist two Δ5-desaturases, one specific for unsaturated acids with
a Δ9-ethylenic bond (active in Taxus but not in Torreya), and the other specific for unsaturated acids with a Δ11-ethylenic bond (active in Torreya but not in Taxus). Our data also highlight the importance of the elongase(s) in the metabolism of fatty acids in Gymnosperm seeds. 14-Methylhexadecanoic
acid, a habitual component of Pinaceae and Ginkgo biloba seed lipids, could not be detected in the Taxaceae studied here. 13C nuclear magnetic resonance spectroscopy of the oils from both genera has confirmed that Δ5-olefinic acids are apparently
excluded from the internal position of triacylglycerols, which is a characteristic common to all Gymnosperm species analyzed
so far, and consequently of great antiquity in their life history. 相似文献
74.
Summary The natural convection of a homogeneous incompressible fluid of grade three between two infinite concentric vertical cylinders is studied. We consider the effect of the non-Newtonian nature of the fluid on the skin friction and heat transfer. Some numerical experimentation is presented to show the effect on the velocity and temperature profiles as the dimensionless parameters are varied. 相似文献
75.
76.
Tullia Gallina Toschi P Capella C Holt W W Christie 《Journal of the science of food and agriculture》1993,61(2):261-266
A rapid procedure has been developed for the isolation of methyl esters of trans-monoenoic fatty acids by silver ion high-performance liquid chromatography. The combined saturated plus trans-monoene fraction was collected for analysis by gas chromatography and comparison with the composition of the unfractionated sample. The trans-monoene contents of partially hydrogenated vegetable oils, determined in this way, are compared with data obtained by Fourier-transform infrared spectroscopy. Alternative methods of base-line correction are discussed. The infrared technique gave values that were a little higher than the chromatographic ones, presumably because the former also detected trans unsaturation in di- and polyunsaturated fatty acids. 相似文献
77.
O Devuyst PT Christie PJ Courtoy R Beauwens RV Thakker 《Canadian Metallurgical Quarterly》1999,8(2):247-257
Dent's disease, which is a renal tubular disorder characterized by low molecular weight proteinuria, hypercalciuria and nephrolithiasis, is associated with inactivating mutations of the X-linked chloride channel, CLC-5. However, the manner in which a functional loss of CLC-5 leads to such diverse renal abnormalities remains to be defined. In order to elucidate this, we performed studies to determine the segmental expression of CLC-5 in the human kidney and to define its intracellular distribution. We raised and characterized antisera against human CLC-5, and identified by immunoblotting an 83 kDa band corresponding to CLC-5 in human kidney cortex and medulla. Immunohistochemistry revealed CLC-5 expression in the epithelial cells lining the proximal tubules and the thick ascending limbs of Henle's loop, and in intercalated cells of the collecting ducts. Studies of subcellular human kidney fractions established that CLC-5 distribution was associated best with that of Rab4, which is a marker of recycling early endosomes. In addition, confocal microscopy studies using the proximal tubular cell model of opossum kidney cells, which endogenously expressed CLC-5, revealed that CLC-5 co-localized with the albumin-containing endocytic vesicles that form part of the receptor-mediated endocytic pathway. Thus, CLC-5 is expressed at multiple sites in the human nephron and is likely to have a role in the receptor-mediated endocytic pathway. Furthermore, the functional loss of CLC-5 in the proximal tubules and the thick ascending limbs provides an explanation for the occurrences of low molecular weight proteinuria and hypercalciuria, respectively. These results help to elucidate further the patho-physiological basis of the renal tubular defects of Dent's disease. 相似文献
78.
J. C. Martin M. C. Dobarganes M. Nour G. Marquez-Ruiz W. W. Christie F. Lavillonnière J.L Sébédio 《Journal of the American Oil Chemists' Society》1998,75(9):1065-1071
Effects of the fatty acid positional distribution and of the triacylglycerol (TG) composition on polymerization of TG during
heat treatment were studied. Diacid TG molecules, acylated only with linoleic acid or linolenic acid along with palmitic acid,
and positioned either in the central position (PLP and PLnP, respectively) or in one of the two outer positions (PPL and PPLn,
respectively) were synthesized. Monoacid TG, i.e., trilinolein and trilinolenin, were also synthesized and mixed with tripalmitin
in a 1:2 ratio. These model TG were also compared to TG models that consisted of a canola oil and its randomized counterpart,
whose fatty acid positional distribution and TG composition were determined by means of high-performance liquid chromatography
(HPLC). After heating, the polymer content and composition were evaluated by HPLC-size exclusion chromatography. Both pure
TG and the canola oil models showed that acylation of polyunsaturated acids in the central position was protective against
polymerization, although the effect was mainly observed with linolenic acid. The synthetic-TG study showed that the monoacid
TG species exhibited higher sensitivity toward polymerization than the diacid species. The slight differences in the TG species
between both canola oils did not allow observation of such a relationship with regard to TG composition. 相似文献
79.
A statistical study of the outcome of inkjet printing, using a reactive dye based ink, on three cellulosic fabrics, namley Lyocell (standard Tencel and Tencel A100) and cotton, pre-treated with urea, migration inhibitor, penetration agent and alkali is reported. Colour strength (as Integ value), absorbed dye fixation and ink penetration were analysed as main responses. A full factorial design method was applied to study the effect of the level of each ingredient in the pre-treatment formulation on the responses, together with the steaming time used for dye fixation. The interactions between variables were also evaluated. The statistically significant variables were determined for each response and contour plots constructed for the most significant interactions to assess where the optimum responses might be achieved. 相似文献
80.