RETRACTED: SENSORY SUGGESTIVENESS AND LABELING: DO SOY LABELS BIAS TASTE?1

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.     

Red cell function at extreme altitude on Mount Everest

As part of the American Medical Research Expedition to Everest in 1981, we measured hemoglobin concentration, red cell 2,3-diphosphoglycerate (2,3-DPG), Po2 at which hemoglobin is 50% saturated (P50), and acid-base status in expedition members at various altitudes. All measurements were made in expedition laboratories and, with the exception of samples from the South Col of Mt. Everest (8,050 m), within 2 h of blood collection. In vivo conditions were estimated from direct measurements of arterial blood gases and pH or inferred from base excess and alveolar PCO2. As expected, increased 2,3-DPG was associated with slightly increased P50, when expressed at pH 7.4. Because of respiratory alkalosis, however, the subjects' in vivo P50 at 6,300 m (27.6 Torr) was slightly less than at sea level (28.1 Torr). The estimated in vivo P50 was progressively lower at 8,050 m (24.9 Torr) and on the summit at 8,848 m (19.4 Torr in one subject). Our data suggest that, at extreme altitude, the blood O2 equilibrium curve shifts progressively leftward because of respiratory alkalosis. This left shift protects arterial O2 saturation at extreme altitude.     

Selective role of calcineurin in haematopoiesis and lymphopoiesis

The calcineurin/NFAT (nuclear factor of activated T-cells) signalling pathway is essential for many aspects of vertebrate development and is the target of the widely used immunosuppressive drugs FK506 and cyclosporine A. The basis for the therapeutic specificity of these drugs has remained unclear, as calcineurin is expressed ubiquitously. By inactivating calcineurin during haematopoietic development, we found that although this signalling pathway has an important, non-redundant role in the regulation of lymphocyte developmental checkpoints, it is not essential for the development of blood myeloid lineages. These studies have shown that the specificity of calcineurin inhibitors arises from the selective use of calcineurin at distinct developmental stages. The requirement for calcineurin/NFAT in the development of the adaptive but not of the innate immune system is consistent with the idea that the evolutionary appearance of this pathway was involved in the emergence of vertebrates.     

Time-lapse video reveals immediate heterogeneity and heritable damage among human ileocecal carcinoma HCT-8 cells treated with raltitrexed (ZD1694)

BACKGROUND: Cellular heterogeneity in drug response has important clinical implications, and is believed to develop over many generations during clonal evolution in human tumors. The purpose of this study was to determine the level of heterogeneity exhibited by sister cells soon after their birth. METHODS: Human ileocecal carcinoma cells (HCT-8) were followed up to 11 days in vitro after a 2-h exposure to 1 microM raltitrexed (IC(95)) in a time-lapse video system. RESULTS: Over five experiments, 414 cells were followed after exposure to raltitrexed. Immediate sterility occurred in 74% of treated cells. Only 6% of cells could produce more than two generations of offspring, and heterogeneity in drug response was seen. Comparing sister cells < 24 h old, the more proliferative sibling produced up to 73 times more offspring, with a median ratio of 9.0 (control median = 1.19). Offspring of prolific drug-treated cells had a decreased probability of division (68% compared with 92%) and an increased average interdivision time (19.0 h compared with 15.1 h). CONCLUSIONS: Short-term exposure to raltitrexed resulted in increased interdivision times and production of sterile offspring extending seven generations. Cellular heterogeneity (difference in proliferation potential comparing drug-treated sister cells) was evident without a period of clonal evolution.