Hélène Pagezy, August 2, 1945 - March 3, 2013

Doctor Hélène Pagezy has recently, and suddenly, passed away after forty years of meticulous anthropological research, conducted mainly in Africa

The evolution of human diets according to the extant primate gut morphology and taste perception

International audienceTaking into account the allometric factors, we found evidence that gut morphology presents a clear similarity in the dietary adaptation of chimpanzees and humans.Nous montrons, en fonction des études comparatives de la morphologie intestinale prenant en compte l'allométrie, que l'adaptation à l'alimentation de l'espèce humain a de grandes similitudes avec celle du chimpanz

Relationships between threshold-based PROP sensitivity and food preferences of Tunisians

International audienceThe extent to which taste responses - and notably the genetically determined sensitivity to 6-npropylthiouracil (PROP) - influences food preferences and food use is still a matter of debate. We addressed the issue on the basis of a behavioural and anthropological study performed in Tunis in 1999. The working sample consists of 123 adults of both sexes (38 men, 85 women), aged 19 to 59, in various social categories. Taste recognition thresholds for sucrose, fructose, sodium chloride, quinine hydrochloride, citric acid, tannic acid, oak tannin and PROP were determined by presenting, in a semi-randomised order (blind-test), series of graded aqueous solutions of each product. Subjects also tasted and rated the pleasantness/unpleasantness of 4 supra-threshold solutions of NaCl and sucrose. All subjects completed a checklist of 43 food items representative of Tunisian diet, rated in terms of flavour, cost, effect on health and prestige on a Labelled Affective Magnitude (LAM) scale. According to the underlying distribution of PROP thresholds, the subjects were separated into three categories: "non-tasters", "medium-threshold tasters", and "low-threshold tasters". Results bring out the specificity of low-threshold tasters, as exhibiting a greater taste sensitivity for most tested substances. Low-threshold taster status is also linked to higher mean food preferences ratings irrespective of sex, age and socio-cultural influences. Tasters as a group (medium-threshold tasters + low-threshold tasters) do not exhibit a higher percentage of food dislikes; however PROP sensitivity is negatively correlated with hedonic responses to NaCl solutions. These results together with the evidence of a limited set of food actually used by low-threshold tasters suggest that these subjects might have difficulties at overcoming an inherent neophobia

Relationship between taste thresholds and hunger under debate

We determined taste recognition thresholds for six compounds (sucrose, fructose, sodium chloride, quinine sulphate, PROP, and liquorice) in fasting students and, in the same subjects, after a meal. The testing procedure was the staircase-method in blind conditions. Although possible variation of taste sensitivity could be linked to internal state (i.e. hormonal status), our results did not show any significant variation of the taste recognition thresholds according to hunger or satiety. Our Bayesian analysis did not corroborate the hypothesis of increased sensitivity to nutrition-related tastants in the fasting state that was recently supported by published data obtained with the two-alternative forced-choice method

La perception gustative des populations autochtone de Yakoutie Arctique (District de Basse-Kolyma) en fonction du régime alimentaire, comparée à celle de populations d'Europe, d'Afrique et du Goroenland

International audienceThresholds of taste recognition have been determined among a Yakutian population sample (n =109), including Yakuts (n =47), some people belonging to aborigenal ethnic minorities of the North (n = 38, including 20 Evens, 14 Yukagirs, 3 Chukchi and 1 Nenets), and 24 persons of other origin (Russians, Ukrainians, etc.), using a blind protocol with solutions of pure (or purified) substances, including oak tanin and tannic acid. Significant differences for sugars perception have been found when comparing the results with those obtained (with a similar protocol) in various European countries and in Africa. These differences are discussed in relation to the environmental conditions and dietary adaptations. In this context, the reactions to sodium chloride, although partly analogous in the Yakutian population sample and among the Inuit of Greenland, do not present the same degree of acuity. This difference could result of an environmental continental adaptive trend, whereas the Inuit have adapted to the arctic coast environmental conditions.Des tests en simple aveugle ont permis de mettre en évidence les seuils de reconnaissance gustative d'une série de produits purifiés, incluant le tannin de chêne et l'acide tannique, sur un échantillon de population (n = 109) de Yakoutie arctique, comprenant des Yakoutes (n =47), des personnes appartenant aux minorités autochtones du Grand Nord (n = 38, soit : 20 Evènes, 14 Youkaguirs, 3 Tchouktches et 1 Nénétse), ainsi que 24 personnes d'autres origines (Russes, Ukrainiens, etc.). Le même type de test ayant été effectué dans plusieurs pays d'Europe ainsi qu'en Afrique, nous avons mis en évidence des différences régionales significatives, portant en particulier sur la perception des sucres, discutées en fonction du milieu et des adaptations au régime alimentaire. Dans ce contexte, la perception du chlorure de sodium par les populations de Yakoutie n'est que partiellement comparable à celle des Inuit du Groenland, car la très grande acuité de perception de ces derniers n'a pas été retrouvée, ce qui impliquerait une adaptation au milieu continental plutôt qu'aux régions côtières arctiques

Elemental analysis of fish feed by laser-induced breakdown spectroscopy

In this study, the potential of laser-induced breakdown spectroscopy (LIBS) as an efficient multi-elemental quantification tool for fish feed is determined. A particular focus of this paper is total chromium, an essential element that has the potential to be toxic and carcinogenic. In total six elements, four macro-elements (Ca, Fe, K and Mg) and two micro-elements (Cr and Rb), were modelled using LIBS spectra of aquafeed samples. Reference analysis was conducted via inductively coupled plasma mass spectrometry (ICP-MS) and showed good agreement with LIBS predictions. These results provide evidence that LIBS has the potential to be utilized in the field as a real-time screening tool for establishing the elemental composition of a range of fish feeds

Migrations et pratiques culinaires

La cuisine, telle qu’elle est pratiquée dans les villes africaines au sud du Sahara, inquiète ses consommateurs. À Yaoundé, les migrants béti et bamiléké s’efforcent d’entretenir l’identité de leur cuisine, tout en faisant face aux dangers pour la santé des nourritures issues des standards de la modernité : trop d’épices, de calories, de gras. Mais cet équilibre lui-même est menacé par manque de temps et du fait de la disparition de certains ingrédients ou de savoir-faire

Mycophenolic Acid overcomes imatinib and nilotinib resistance of chronic myeloid leukemia cells by apoptosis or a senescent-like cell cycle arrest.

International audienceWe used K562 cells sensitive or generated resistant to imatinib or nilotinib to investigate their response to mycophenolic acid (MPA). MPA induced DNA damage leading to cell death with a minor contribution of apoptosis, as revealed by annexin V labeling (up to 25%). In contrast, cell cycle arrest and positive staining for senescence-associated β-galactosidase activity were detected for a large cell population (80%). MPA-induced cell death was potentialized by the inhibition of autophagy and this is associated to the upregulation of apoptosis. In contrast, senescence was neither decreased nor abrogated in autophagy deficient K562 cells. Primary CD34 cells from CML patients sensitive or resistant to imatinib or nilotinib respond to MPA although apoptosis is mainly detected. These results show that MPA is an interesting tool to overcome resistance in vitro and in vivo mainly in the evolved phase of the disease

Stratégies de subsistance et Perception des aliments des populations autochtones de Yakoutie arctique (Districts de Basse et de Moyenne Kolyma)

Une étude des appréciations de différents aliments et de la perception gustative a été réalisée sur un échantillon de populations autochtones de Yakoutie arctique, composé de 102 Evènes, 52 Yakoutes et 22 Tchouktches. Afin de compléter les réponses, sur des échelles analogiques, correspondant à 69 items alimentaires, des tests en simple aveugle avec des solutions de saccharose, de chlorure de sodium et de PROP (6-n-propylthiouracile) ont permis de déterminer la typologie de goûteur/non-goûteur au PROP et le caractère hédonique (plaisant/déplaisant) des différentes concentrations. Les données ont été analysées en fonction de l’âge, du sexe, du groupe ethnique et des conditions écologiques locales. Les variations des appréciations alimentaires traduisent les stratégies de subsistance, avec des différences significatives entre groupes ethniques correspondant aux conditions environnementales et historiques de chacune des populations considérées. Les facteurs sensoriels, et notamment le statut de goûteur/non-goûteur au PROP, n’apparaissent pas comme des marqueurs pertinents des appréciations alimentaires.A study of food preferences of the indigenous peoples of Arctic Yakutia was conducted on a population sample consisting of 102 Evens, 52 Yakuts and 22 Chukchis. Responses recorded on analogue scales corresponding to 69 food items have been supplemented by blind tests concerning the perception of solutions of sucrose, sodium chloride, and PROP, to determine hedonic responses to salt and to sucrose (sweet likers vs. sweet dislikers) and the PROP status (tasters vs. non-tasters). Data were computed in relation to age, sex, ethnic groups and ecological factors. Subsistence patterns and food preferences appear to be related, and significant ethnic differences in mean preferences mirror the environmental and historical backgrounds of the various populations. Sensory factors, and notably the PROP status, do not appear as significantly determining food preferences

Nutrition Transition and Biocultural Determinants of Obesity among Cameroonian Migrants in Urban Cameroon and France.

Native of rural West Cameroon, the Bamiléké population is traditionally predisposed to obesity. Bamiléké who migrated to urban areas additionally experience the nutrition transition. We investigated the biocultural determinants of obesity in Bamiléké who migrated to urban Cameroon (Yaoundé), or urban France (Paris). We conducted qualitative interviews (n = 36; 18 men) and a quantitative survey (n = 627; 266 men) of adults using two-stage sampling strategy, to determine the association of dietary intake, physical activity and body weight norms with obesity of Bamiléké populations in these three socio-ecological areas (rural Cameroon: n = 258; urban Cameroon: n = 319; urban France: n = 50). The Bamiléké valued overweight and traditional energy-dense diets in rural and urban Cameroon. Physical activity levels were lower, consumption of processed energy-dense food was frequent and obesity levels higher in new migrants living in urban Cameroon and France. Female sex, age, duration of residence in urban areas, lower physical activity and valorisation of overweight were independently associated with obesity status. This work argues in favour of local and global health policies that account for the origin and the migration trajectories to prevent obesity in migrants