Biomedical subjects

Hendrik N J Schifferstein

Publications and source records attributed to Hendrik N J Schifferstein.

7 recordsLinked to original sources

PubMed2005

Stimulation of liver-directed cholesterol flux in mice by novel N-acetylgalactosamine-terminated glycolipids with high affinity for the asialoglycoprotein receptor.

OBJECTIVE: Interventions that promote liver-directed cholesterol flux can suppress atherosclerosis, as demonstrated for scavenger receptor-BI overexpression in hypercholesterolemic mice. In analogy, we speculate that increasing lipoprotein flux to the liver via the asialoglycoprotein receptor (ASGPr) may be of therapeutic value in hypercholesterolemia. METHODS AND RESULTS: A bifunctional glycolipid (LCO-Tyr-GalNAc3) with a high-nanomolar affinity for the ASGPr (inhibition constant 2.1+/-0.2 nmol/L) was synthesized that showed rapid association with lipoproteins on incubation with serum. Prior incubation of LCO-Tyr-GalNAc3 with radiolabeled low-density lipoprotein or high-density lipoprotein (0.5 microg/microg of protein) resulted in a dramatic induction of the liver uptake of these lipoproteins when injected intravenously into mice (70+/-3% and 78+/-1%, respectively, of the injected dose at 10 minutes of low-density lipoprotein and high-density lipoprotein), as mediated by the ASGPr on hepatocytes. Intravenously injected LCO-Tyr-GalNAc3 quantitatively incorporated into serum lipoproteins and evoked a strong and persistent (> or =48 hour) cholesterol-lowering effect in normolipidemic mice (37+/-2% at 6 hours) and hyperlipidemic apoE(-/-) mice (32+/-2% at 6 hours). The glycolipid was also effective on subcutaneous administration. CONCLUSIONS: LCO-Tyr-GalNAc3 is very effective in promoting cholesterol uptake by hepatocytes and, thus, may be a promising alternative for the treatment of those hyperlipidemic patients who do not respond sufficiently to conventional cholesterol-lowering therapies.

Acetylgalactosamine↗

PubMed2005

The perceived importance of sensory modalities in product usage: a study of self-reports.

Although popular belief holds that vision dominates human experience, this does not necessarily imply that people regard vision as the most important sensory modality during the interaction with every product. Instead, the relative importance of the different modalities is likely to depend on the type of product and on the task performed. In Study 1, respondents reported how important they found vision, audition, touch, taste, and smell during the use of 45 different products. In Study 2, the respondents answered a similar question for the evaluation of the safety, ease of use, and enjoyment experienced for 15 products. Importance ratings for the sensory modalities differed considerably between the products. Differences due to the types of evaluations were smaller. Averaged over products and evaluation types, vision was the most important sensory modality for product evaluations, followed by touch, smell, audition, and taste. However, for about half of the individual products, the importance ratings for vision were lower than for one of the other modalities. These findings are in line with the view that vision is regarded the dominant modality, because it plays an important part in many and an irrelevant part in virtually no product experiences.

Adolescent↗

PubMed2004

Capturing product experiences: a split-modality approach.

When people interact with products, all sensory modalities are open to receive information. To assess each modality's potential contribution to overall product experiences, we developed a split-modality approach, in which subjects experienced real-life products through only one modality: vision, touch, audition, or olfaction. Responses focused on (1) description of the sensory experience, (2) product identification, and (3) descriptions of associations and memories linked to this experience. Visual and tactual information were most detailed, made product identification easiest, and yielded the clearest memories of past events, associations to persons, and associations with other products. Because vision may have an advantage over touch by the speed with which information is processed, vision is likely to dominate product experiences in real-life situations.

Acoustic Stimulation↗

PubMed2004

Visualising fragrances through colours: the mediating role of emotions.

To facilitate communication about fragrances, one can use the colours people tend to associate with their smells. We investigated to what extent odour-colour correspondences for fine fragrances can be accounted for by underlying emotional associations. Odour-colour matches and degree-of-fit judgments revealed that odours were matched to colours non-randomly. Matching colours differed mainly on blackness (brightness), and less on chromaticness (saturation) and hue. Furthermore, we found a consistent negative relationship between odour-colour degree-of-fit ratings and the difference between the odour scores and the colour scores on one of the emotion dimensions (pleasure). This suggests that emotional associations may partly underlie odour-colour correspondences.

Adult↗

PubMed2004

Modeling panel detection frequencies by queuing system theory: an application in gas chromatography olfactometry.

In continuous vigilance tasks, the number of coincident panel responses to stimuli provides an index of stimulus detectability. To determine whether this number is due to chance, panel noise levels have been approximated by the maximum coincidence level obtained in stimulus-free conditions. This study proposes an alternative method by which to assess noise levels, derived from queuing system theory (QST). Instead of critical coincidence levels, QST modeling estimates the duration of coinciding responses in the absence of stimuli. The proposed method has the advantage over previous approaches that it yields more reliable noise estimates and allows for statistical testing. The method was applied in an olfactory detection experiment using 16 panelists in stimulus-present and stimulus-free conditions. We propose that QST may be used as an alternative to signal detection theory for analyzing data from continuous vigilance tasks.

Adult↗

PubMed2002

The signal function of thematically (In)congruent ambient scents in a retail environment.

An odor emitted by an object signals the presence of that object and may draw attention to it. Can odors that are not actually emitted by an object also function as a signal? We investigated whether the degree of thematic congruency between an ambient odor and a magazine affected magazine sales in a retail store. We selected two odors: a grass odor, congruent with soccer, animal/nature and gardening magazines; and a sunflower odor, congruent with personal care and women's magazines. In a field study in three bookstores, the ambient odors did not increase sales for thematically congruent magazines, nor did they decrease sales for incongruent magazines. Several explanations for these unexpected findings are discussed.

Adolescent↗

PubMed2002

Effects of appropriate and inappropriate odors on product evaluations.

In accounting for an odorant's effect on the evaluation of a product, both the odor's intrinsic pleasantness and its appropriateness for that particular product are relevant. When comparing the effects of pleasant smells, consumers are likely to prefer products with appropriate smells to those with an inappropriate smell. We investigated the effect of adding congruent and incongruent odorants on product evaluations for each of three product categories: food (tea, instant whip, cake mix), personal care (shampoo, deodorant, lip balm), and household products (cream cleaner, air freshener, furniture wax). In a between-subjects design, 96 respondents judged scented and unscented products presented in commercial packages of major national brands. The respondents assessed the overall evaluation, 14 to 19 beliefs about the product, buying intention, and the frequency of use for each product. Respondents were instructed to evaluate each product as they would in a store. Although congruency ratings between odor and product show that the manipulation of congruency was successful, no main effect was found for the congruency on overall evaluations of the products. To account for this unexpected finding, we speculate that congruency between odor and product may be more important during product consumption or product use than during its selection. In addition, the odor's effects may have been attenuated in our experiment because we asked our respondents to rate each product on the attribute 'has a nice smell'.

Adolescent↗