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Can labels suggestively influence sensory perceptions and taste? Using a “ Phantom Ingredient” taste test, we show that the presence or absence of a labeled ingredient (soy) and the presence or absence of a health claim negatively bias taste perceptions toward a food erroneously thought to contain soy. We found a label highlighting soy content made health claims believable but negatively influenced perceptions of taste for certain segments of consumers. Our results and discussion provide better direction for researchers who work with ingredient labeling as well as for those who work with soybean products. 相似文献
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The transport of free polymannose-type oligosaccharides from the lumen of
the endoplasmic reticulum into the cytosol has been recently demonstrated
(Moore,S.E.H., et al., 1995, EMBO J., 14, 6034-6042), but at present little
is known of the characteristics of this process. Here, it is shown that
inhibition of the transport of endogenously synthesized metabolically
radiolabeled free oligosaccharides out of the endoplasmic reticulum into
the cytosol of permeabilized HepG2 cells occurs when assays are conducted
in the presence of mannose (IC50, 4.9 mM), or its derivatives modified at
the first carbon (C1) of the sugar ring; alpha-methyl mannoside (IC50, 2.0
mM), mannoheptulose (IC50, 1.6 mM), and alpha-benzyl mannoside (IC50, 0.8
mM), whereas other monosaccharides (50 mM), differing from mannose at
position; C2 (glucose), C3 (altrose), C4 (talose), C5 (l-rhamnose), and C6
(mannoheptose), have little effect. N-Acetylglucosamine does not inhibit
oligosaccharide transport and, furthermore, although mannobioses and a
mannotriose inhibit free oligosaccharide transport, di-N-acetylchitobiose
is without effect. It is also shown that if the transport assay buffer is
either depleted of calcium ions, or supplemented with the Ca2+/Mg2+ATPase
inhibitor, thapsigargin, or with calcium ionophores, free oligosaccharide
transport out of the endoplasmic reticulum is inhibited. These results
demonstrate that the terminal nonreducing mannosyl residues of free
polymannose-type oligosaccharides and not their
N-acetylglucosamine-containing reducing termini, play an important role in
the interaction of the free oligosaccharide with the transport machinery,
and that this transport process requires the presence of calcium
sequestered in the lumen of the endoplasmic reticulum.
相似文献
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Thus far the life cycle of Trypanosoma (Megatrypanum) theileri has not been studied. We collected tabanids during the mass hatching, when only few tabanids are infected with trypanosomes. Tabanids were caught immediately after attacking a bait cow to serve as controls or after they had been allowed to engorge on the Trypanosoma (M.) theileri-infected cow. Tabanids were kept in the laboratory and used to study the developmental cycle of T. (M.) theileri in the tabanid gut. From day 1 to day 10 the presumably unfed controls and the engorged tabanids were dissected and cytological smears made from the mid- and hindgut. In total 2.6% (1/38) of the controls and 39% (23/59) of the engorged tabanids were positive for trypanosomes in the 1991 season. From day 1 to day 4 after engorgement trypanosomes were found in the midgut. Epimastigotes with a length of 29 μm on day 1 after infection multiplied by inequal division to form smaller epimastigotes of 26 μm on day 3. On day 4 morphologically indistinguishable trypanosomes of 21 μm total length were found in both mid- and hindgut. From day 5 to day 10 trypanosomes were found only in the hindgut in which the transformation to metacyclics was demonstrated, i.e. epimastigotes transformed to amastigote stages of 5 μm in total length. 相似文献
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A pair of chimeric twins, T.S. (male) and M.R. (female) first examined in 1970 are reinvestigated in order to determine if the proportions of admixture of red cells in their blood are unchanged, and if erythrocytes and leukocytes show the same percentage of admixture. T.S., M.R. and their family are investigated for HLA, serum types, and erythrocyte antigens and enzymes. A quantitative determination of 'foreign' cell populations in the blood of each twin is attempted for the systems ABO, and HLA, and for sex chromosomes in PHA stimulated lymphocytes. The results for the ABO system obtained by agglutination technique and by a double-layer immunofluorescence technique indicate that the population of M.R. erythrocytes in T.S. has decreased during the 7-year period, and is now below half the size found in 1970. Erythrocytes and leukocytes show the same percentage of admixture in both twins. 相似文献
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We have shown previously that the β-adrenergic agonist isoproterenol (2μM) and the phosphodiesterase inhibitor isobutylmethylxanthine (1 mM) produce a much greater increase in cyclic AMP in human leukocytes that have been pretreated with colchicine (or with other agents that affect microtubule assembly) than in control leukocytes. The effects of colchicines were both time- and dose-dependant. These and other data suggested that the generation of cyclic AMP is normally restricted by an intact system of cytoplasmic microtubules. If so, then the same time and dose dependencies might apply to other colchicines-induced changes in leukocyte function. We have now assayed the distribution of concanavalin A (Con A)-receptor complexes on the leukocyte membrane, taking into account that leukocytes competent to assemble microtubules show a uniform distribution of surface- bound Con A whereas microtubule-deficient cells accumulate Con A in surface caps. We have found that the effect of colchicine on capping is also both time- and dose dependent, and that the dose-response relationships conform to those required to increase cyclic AMP levels. These findings provide further evidence that both colchicine-induced Con-A capping and colchicine- induced cyclic AMP generation depend upon the relaxation of constraints normally imposed by cytoplasmic microtubules upon the plasma membrane, which limit, respectively, lateral mobility of the lectin-receptor complexes, and expression of hormone-sensitive adenylate cyclase. Moreover, colchicine-induced Con-A cap formation is not affected even by very large changes in leukocyte cyclic AMP levels. Thus, elevated cyclic AMP levels do not appear to promote the dissolution of microtubules; rather, the dissolution of microtubules permits the generation of increased amounts of cyclic AMP. 相似文献
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