THE EMOTIONAL POWER OF ODORS: IDENTIFYING THE DIMENSIONS REFERRING TO FEELINGS PRODUCED BY ODORS

Abstract There is broad literature on the emotional effect of odors but, so far, little concern with the precise mechanism underlying the elicitation of emotions via olfactory stimuli. One reason for this neglect might be the lack of answers to a major question that underlie any research on odors and emotions: What exactly are the emotions associated to odors and how are they organised? The major issue addressed in the present paper concerns the nature of the verbal labels that refer to the specific states produced by odors. We conducted a series of studies in order to examine which terms are best suited to describe the feelings associated to odors and autobiographical memories. In Study 1, the relevance of a broad list of candidate affect terms to describe odor-related feelings was examined by two groups of participants with different level of knowledge about odors. In study 2, the most relevant terms retained from study 1 were evaluated with actual odorant samples and the data were submitted to a series of exploratory factor analyses to reduce the set of variables to a smaller set of summary-scales and to get a preliminary sense of the differentiation of affects elicited by odors. The Study 3 replicated Study 2 with a larger and more representative sample of odorant samples and participants. Overall, the findings point to a structure of affective responses to odors that differs from the more traditional taxonomies of emotion such as posited by discrete emotion or dimensional theories and suggest that affective states elicited by odors are structured around few dimensions that clearly reflect the role of olfaction in social interactions, danger prevention and arousal/relaxation sensations

Sub-lethal radiation enhances anti-tumor immunotherapy in a transgenic mouse model of pancreatic cancer

BACKGROUND: It is not uncommon to observe circulating tumor antigen-specific T lymphocytes in cancer patients despite a lack of significant infiltration and destruction of their tumors. Thus, an important goal for tumor immunotherapy is to identify ways to modulate in vivo anti-tumor immunity to achieve clinical efficacy. We investigate this proposition in a spontaneous mouse tumor model, Rip1-Tag2. METHODS: Experimental therapies were carried out in two distinctive trial designs, intended to either intervene in the explosive growth of small tumors, or regress bulky end-stage tumors. Rip1-Tag2 mice received a single transfer of splenocytes from Tag-specific, CD4(+) T cell receptor transgenic mice, a single sub-lethal radiation, or a combination therapy in which the lymphocyte transfer was preceded by the sub-lethal radiation. Tumor burden, the extent of lymphocyte infiltration into solid tumors and host survival were used to assess the efficacy of these therapeutic approaches. RESULTS: In either intervention or regression, the transfer of Tag-specific T cells alone did not result in significant lymphocyte infiltration into solid tumors, not did it affect tumor growth or host survival. In contrast, the combination therapy resulted in significant reduction in tumor burden, increase in lymphocyte infiltration into solid tumors, and extension of survival. CONCLUSIONS: The results indicate that certain types of solid tumors may be intrinsically resistant to infiltration and destruction by tumor-specific T lymphocytes. Our data suggest that such resistance can be disrupted by sub-lethal radiation. The combinatorial approach presented here merits consideration in the design of clinical trials aimed to achieve T cell-mediated anti-tumor immunity

When Flexibility Is Stable: Implicit Long-Term Shaping of Olfactory Preferences

Preferences are traditionally assumed to be stable. However, empirical evidence such as preference modulation following choices calls this assumption into question. The evolution of such postchoice preference over long time spans, even when choices have been explicitly forgotten, has so far not been studied. In two experiments, we investigated this question by using a variant of the free choice paradigm: In a first session, participants evaluated the pleasantness of a number of odors. We then formed pairs of similarly rated odors, and asked participants to choose their favorite, for each pair. Participants were then presented with all odors again, and asked for another pleasantness rating. In a second session 1 week later, a third pleasantness rating was obtained, and participants were again asked to choose between the same options. Results suggested postchoice preference modulation immediately and 1 week after choice for both chosen and rejected options, even when choices were not explicitly remembered. A third experiment, using another paradigm, confirmed that choice can have a modulatory impact on preferences, and that this modulation can be long-lasting. Taken together, these findings suggest that although preferences appear to be flexible because they are modulated by choices, this modulation also appears to be stable over time and even without explicit recollection of the choice. These results bring a new argument to the idea that postchoice preference modulation could rely on implicit mechanisms, and are consistent with the recent proposal that cognitive dissonance reduction could to some extent be implicit

Effects of sodium lactate on ventilation and acid-base balance in healthy humans

Sodium lactate inhibits ventilation when infused in healthy human subjects. This effect has been attributed to lactate-induced metabolic alkalosis. In order to further delineate the mechanisms responsible for this depression of ventilation, healthy humans were infused with sodium lactate with or without acetazolamide. Sodium lactate increased blood pH from 7.37 +/- 0.02 to 7.47 +/- 0.01 and induced a sustained urinary excretion of bicarbonate. PO2 of arterialized blood decreased by 10.3 +/- 2.1 mmHg, indicating an inhibition of ventilation. Acetazolamide decreased lactate-induced alkalinisation of blood (pH after lactate + acetazolamide 7.42 +/- 0.02), but did not prevent the drop in PO2. Acetazolamide alone tended to stimulate ventilation, as indicated by an increase in PO2. These results indicate that sodium lactate inhibits ventilation independently of changes in systemic blood pH. Alkalinization of the cerebrospinal fluid, or other central effects of lactate, is probably responsible for this ventilatory depression

Nutritional status and food intake in nine patients with chronic low-limb ulcers and pressure ulcers: importance of oral supplements

OBJECTIVES: Chronic low-limb ulcers and pressure ulcers are a serious and costly issue. Malnutrition is a risk factor. Searching for intervention strategies in elderly patients referred for surgical closure of their ulcers, the trial aimed at investigating the micronutrient status, determining the food intake of such patients, and the role of oral liquid supplements. METHODS: Observational cohort study in 9 patients, starting 5 days prior to surgery until day 10 after surgery. Variables: body mass index (BMI), food intake assessed using standardized meals (energy target 25 kcal/kg/day). Oral liquid supplements were provided between meals. Laboratory: blood count, plasma proteins, antioxidant status, vitamins, Fe, Se, and Zn. RESULTS: The patients were aged 71+/-10 y (mean+/-SD), with a BMI of 23.3+/-3.3. Baseline blood samples showed anemia and strong inflammation in 4 patients: albumin, retinol, and selenium were low; iron and zinc were very low. Food intake was largely variable and covered only about 76% (31-95%) of energy requirements. Breakfast provided 225+/-110, lunch 570+/-215, and dinner 405+/-150 kcal. Supplements were willingly consumed covering 35+/-12% of energy target. While vitamin supply was adequate, selenium and zinc requirements were not met. CONCLUSIONS: Most patients with chronic skin ulcers suffered micronutrient status alterations, and borderline malnutrition. Meals did not cover energy requirements, while oral supplements covered basic micronutrient requirements and compensated for insufficient oral energy and protein intakes, justifying their use in hospitalized elderly patients

A 10-year survey of nutritional support in a surgical ICU: 1986-1995

Total parenteral nutrition (TPN) has long been considered the optimal nutrition technique in critically ill patients, but recently the use of enteral nutrition (EN) has increased. This study describes the evolution of the different nutritional support techniques in a surgical intensive care unit (ICU) in a university hospital, through (1) a global survey over 10 y assessing the evolution of the use of EN and TPN, and (2) a prospective study performed over 6 mo. Severity of illness and diagnostic categories were stable (n = 11,539 patients). From 1986 to 1990, the proportion of TPN administered increased from 10-25% of ICU days, decreasing to 10% thereafter. EN was used in about 5% of ICU days in 1986, and had increased to 30% of total ICU treatment days in 1995. The proportion of nutrients actually delivered to the patients was 75% with EN and 88% with TPN. Major changes in nutritional support have been observed since 1986. The frequency of nutritional support provided in general has increased to 40% of ICU treatment days. TPN has been largely overtaken by EN, with the risk of insufficient energy delivery, related to the difficulties of EN in the critically ill. These results reinforce the importance of continuous quality control by daily assessment of nutrient supply

Malnutrition en soins intensifs: discussion d'un cas difficile. [Malnutrition and intensive care: discussion on a difficult case]

Hospital malnutrition is an insidious problem which is responsible for many complications. Critically ill patients are frequently hypermetabolic with increased nutritional requirements, and are exposed to the risk of underfeeding. The case report presents the case of a patient which stayed 22 days in the intensive care unit (ICU), and whose nutritional support failed: he ultimately died of surgical and infectious complications. An optimal support includes a early metabolic support provided as glucose-insulin-potassium infusion and antioxidant micronutrients, with an enteral nutrition initiated on days 3 or 4. It is frequently difficult to reach energy targets with exclusive enteral nutrition: if the latter is not reached after 5-6 days of enteral feeding, combination with parenteral nutrition enables worsening of the energy deficit. Transition to oral feeding is another critical event which may expose the patient to underfeeding: prescription of oral supplements and/or maintenance of overnight enteral feeding providing 50-75% of energy requirements helps overcome this period. The case illustrates the importance of monitoring daily and cumulated energy balance

Influence of early trace element and vitamin E supplements on antioxidant status after major trauma: a controlled trial

Negative selenium and zinc balances occur after major trauma, potentially compromising antioxidant defenses. The aim of this study was to determine if micronutrient supplementation could modulate the blood antioxidant status. 32 patients admitted to surgical ITU with major trauma were randomized to receive either selenium alone, selenium plus copper, zinc and tocopherol, or placebo for 5 days after injury. Blood samples were collected on days 0, 1, 2, 5, 10 and 20 and analyzed for plasma selenium, copper, zinc, tocopherol, glutathione peroxidase and total antioxidant capacity (TAC), and for erythrocyte antioxidant enzymes. Plasma selenium and tocopherol concentrations were low on admission, but increased significantly (p = 0.001) with supplementation, whereas there was an early significant fall in TAC (p < 0.002) in the selenium supplemented groups. Plasma glutathione peroxidase activity increased significantly between days 2 and 5 with supplementation (p = 0.02), but erythrocyte enzyme activity was unaffected. The unexpected early fall in plasma TAC with supplementation may reflect mobilization of antioxidant defenses. O 2001 Elsevier Science Inc. All rights reserved