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PubMed1984

[Analysis of the effect of cholecystokinin octapeptide on the monoamine level in rat brain limbic structures in the process of satiation].

The authors studied the changes in monoamine levels in rat brain limbic structures during natural satiation and satiation after intraperitoneal injection of cholecystokinin octapeptide (CCK-8) in doses 5 and 10 micrograms/kg following 24- and 48-hour food deprivation. Injection of CCK-8 was found to reduce food consumption in hungry rats by 2.5 times on an average. Of the test animals, 25% appeared resistant to CCK-8, showing no reduction in food consumption. Satiation after the 24-hour food deprivation caused characteristic changes in the levels of noradrenaline, dopamine and serotonin in the limbic structures of the brain, similar to the changes in monoamine levels in the limbic structures of animals, in which food motivation was suppressed by injection of CCK-8. The responses of the monoaminergic system of the brain limbic structures to satiation induced by CCK-8 injection after the 48-hour food deprivation differed qualitatively from the responses to natural satiation. It is concluded that the inhibitory action of CCK-8 on food motivation in rats determined by the 24-hour fasting is likely to be mediated via the monoamine system of the hypothalamus, tonsils and hippocamp. However, the data obtained suggest a different mechanism of the satiating action of CCK-8 under marked food motivation after long-term periods of food deprivation.

Animals↗

PubMed1994

Deamidation of food proteins to improve functionality.

Many proteins, particularly those in plants, require structural modifications to improve their functional properties for expanded use. Several chemical and enzymatic methods are described for food protein deamidation to improve solubility, emulsification, foaming, and other functional properties of the proteins. The use of enzymes in protein modification is more desirable than chemical treatments because of their speed, mild reaction conditions, and their high specificity. Transglutaminase, protease, and peptidoglutaminase (PGase) are the only enzymes reported in the literature for protein deamidation. Of these, PGase appears to be the most feasible for practical application. PGase production, purification, and use in deamidation are discussed.

Amides↗

PubMed1988

Fat aversion in eating disorders.

Patients with eating disorders are reported to show an irrational dislike of starchy foods, sometimes described as a "carbohydrate phobia". In the present study, food-related attitudes and self-reported food preferences of women patients with anorexia nervosa (N = 13), anorexia with bulimia (N = 16) and bulimia (N = 14) were mapped using multidimensional scaling (MDS) procedures and compared to those of normal-weight controls (N = 49). Sixteen common food names were rated along 9-point category scales for their nutritional similarity, perceived macronutrient content, caloric density and overall nutritional value. MDS (SINDSCAL) and property fitting (PROFIT) procedures revealed that eating disorder patients associated calories with fat content to a greater extent than did controls, and tended to dislike high-fat foods. In contrast, no differences in perceptions or preferences for carbohydrate foods were observed. Anorectic restrictor patients showed the most rigid attitude structure, expressing preferences only for the lowest calorie and the most nutritious foods. The present multivariate techniques of mapping perceptual space may help to distinguish between diagnostic subgroups in studies of eating disorders.

Adolescent↗

PubMed1972

High-resolution autoradiography of malarial parasites treated with 3 H-chloroquine.

Electron microscope autoradiography was performed on the erythrocytic stages of the rodent malarial parasite, Plasmodium berghei, after exposure to (3)H-Chloroquine. (3)H-Chloroquine becomes selectively localized within the parasite food vacuoles 1 hour after it is administered, and remains in this structure for up to 24 hours. This study indicated that the food vacuoles were the primary site of chloroquine concentration within the parasite.

Animals↗

PubMedDate not supplied

Anatomical and histological changes in the alimentary tract of migrating blackcaps (Sylvia atricapilla): a comparison among fed, fasted, food-restricted, and refed birds.

During northward migration, blackcaps that arrive to refuel at stopover sites in Israel's Negev Desert have reduced masses of organs that are important in food digestion and assimilation. We tested several predictions from the general hypothesis that smaller organs of digestion (small intestine and pancreas) and nutrient assimilation (liver) bring about a lower capacity to consume food and that the organs must be restored before blackcaps can feed and digest at a high rate. We used a fasting protocol to create a group of blackcaps with reduced intestine and liver mass (reduced by 45% and 36%, respectively) compared with controls fed ad lib. Because most of the small intestine's biochemical digestive capacity reside in enterocytes found on villi, we predicted and found that reduced intestinal mass in fasted blackcaps related mainly to changes in enterocytes rather than other cells and tissues such as nonabsorptive crypt cells or underlying muscle. Because migrating blackcaps that stop over to feed begin to increase in body mass only 2 d after arrival, we predicted and found a similar recovery period in blackcaps that were first fasted but then refed--the organ mass, structure, function, and ability to consume food was restored after 2 d of feeding. Another group of food-restricted blackcaps (fed at one-third ad lib. level) lost similar amounts of body mass as fasted blackcaps but had much greater capacity to consume food than fasted blackcaps, and so we predicted that they would exhibit little or no reduction in alimentary organs relative to controls fed ad lib. A surprising result was that, as in fasted blackcaps, in food-restricted blackcaps, the decreases in masses of small intestine, liver, and pancreas were proportionally greater than the decreases in body mass or in masses of nonalimentary organs (heart, pectoralis). Food restriction, like fasting, caused a decrease in amount of intestinal mucosa and an alteration in the phenotype of enterocytes. These results are thus not consistent with the general hypothesis, and although they can be rationalized by assuming that blackcaps fed ad lib. have excess digestive capacity, it may also be that the physiological process or processes limiting very high feeding rate lie elsewhere than in the digestive system.

Adaptation, Physiological↗

PubMed1985

Polysaccharides and food processing.

The rôle of polysaccharides during processing and for the quality of foods is discussed. Starch is the most important energy source for man. Most other polysaccharides are not metabolized for energy, but play an important rôle as dietary fibres. Pectins, alginates, carrageenans, and galactomannans are discussed as functional food additives in relation to their structure and their rheological behaviour, stability and interactions. Endogenous polysaccharides of fruits and vegetables and in products derived from them are responsible for such phenomena as texture (changes), press yields, ease of filtration and clarification, cloud stability, and mouth feel. To achieve desirable properties, the action of endogenous enzymes on polysaccharides must be inactivated and/or exogenous enzymes added as processing aids. This is also true for overcoming haze phenomena in clear juices or to break down undesirable microbial polysaccharides. Dough properties for bread baking can be improved by enzymic breakdown of a restrictive pentoglycan network. Network formation may come about by oxidative coupling of phenol rings of ferulic acid bound to hemicelluloses by ester links. Gels may be made by inducing oxidative coupling in natural or synthetic systems. Stagnation in development of new polysaccharide food additives is ascribed to difficulties in obtaining government approval for food use.

Carbohydrate Conformation↗

PubMed2001

Strengthening environmental and educational nutrition programmes in worksite cafeterias and supermarkets in The Netherlands.

The purpose of this study was to assess conditions for the adoption and continued implementation of different healthy nutrition programmes in worksite cafeterias and supermarkets, i.e. an educational programme and two environmental programmes (a food labelling programme and a food supply programme). Twenty semi-structured interviews were conducted with representatives of worksite cafeterias and supermarkets. Concepts of theories of diffusion were used as a framework for the study. Questions were formulated about the attributes of the innovation, and organizational and personal characteristics that might influence programme adoption and implementation. Results indicated that educational and environmental programmes in both worksite cafeterias and supermarkets should meet specific requirements regarding programme design, methods and materials in order to be adopted and implemented. Besides, some important implementation strategies of the educational and environmental programmes were identified. It is concluded that it seems feasible to conduct educational and environmental intervention programmes in worksite cafeterias and supermarkets, but that certain conditions for adoption and continued implementation have to be met. Based on the implications of this study, the development of an educational programme, a labelling programme and a food supply programme was completed.

Decision Making, Organizational↗

PubMed1999

Structural changes of hake (Merluccius merluccius L.) fillets: effects of freezing and frozen storage.

Structural changes in hake (Merluccius merluccius L.) fillets as affected by freezing method and frozen storage temperature have been studied through Raman spectroscopy and related to changes in texture and functionality. Changes in protein secondary structure were observed due to storage temperature, accompanied by changes in apparent viscosity and shear resistance. Samples at -10 degrees C showed greater structural alteration than at -30 degrees C in terms of increase of beta-sheets at the expense of alpha-helices. An increase of unordered protein structure was found only in samples stored at -10 degrees C. Exposure of buried tryptophan residues was observed at both storage temperatures. The decrease of the deltaCH(2) band upon storage suggested an increase of hydrophobic interactions of aliphatic residues. Except for liquid air frozen fillets, all samples showed a decrease of the nuO-H/nuC-H band ratio compared to the fresh ones, this decrease being higher the harsher the conditions.

Animals↗

PubMed2006

[Soybean allergens and hypoallergenic germplasm enhancement].

Food allergy is a public sanitary problem which has received attention worldwide. It is becoming an increasingly interesting problem to decrease the concentration of allergens for improvement of the food security. Soybean allergens in seeds are composing of storage proteins, structure proteins, and disease-related proteins. Among them, Gly m Bd 28K, Gly m Bd 30K and Gly m Bd 60K are the major allergens located in 7S conglycinin fragments. By recognizing allergens' physicochemical property, hypersensitivity and gene structure, certain progresses had been made to reduce the concentration of allergens in soybean through food processing, traditional breeding and genetic engineering. The paper reviewed the sorts and characters of soybean allergens, the physicochemical property of the three immunodominant allergens and their gene structures. Progress in developing hypoallergenic cultivars was also discussed.

Allergens↗

PubMed2001

Dietary protein and weight reduction: a statement for healthcare professionals from the Nutrition Committee of the Council on Nutrition, Physical Activity, and Metabolism of the American Heart Association.

High-protein diets have recently been proposed as a "new" strategy for successful weight loss. However, variations of these diets have been popular since the 1960s. High-protein diets typically offer wide latitude in protein food choices, are restrictive in other food choices (mainly carbohydrates), and provide structured eating plans. They also often promote misconceptions about carbohydrates, insulin resistance, ketosis, and fat burning as mechanisms of action for weight loss. Although these diets may not be harmful for most healthy people for a short period of time, there are no long-term scientific studies to support their overall efficacy and safety. These diets are generally associated with higher intakes of total fat, saturated fat, and cholesterol because the protein is provided mainly by animal sources. In high-protein diets, weight loss is initially high due to fluid loss related to reduced carbohydrate intake, overall caloric restriction, and ketosis-induced appetite suppression. Beneficial effects on blood lipids and insulin resistance are due to the weight loss, not to the change in caloric composition. Promoters of high-protein diets promise successful results by encouraging high-protein food choices that are usually restricted in other diets, thus providing initial palatability, an attractive alternative to other weight-reduction diets that have not worked for a variety of reasons for most individuals. High-protein diets are not recommended because they restrict healthful foods that provide essential nutrients and do not provide the variety of foods needed to adequately meet nutritional needs. Individuals who follow these diets are therefore at risk for compromised vitamin and mineral intake, as well as potential cardiac, renal, bone, and liver abnormalities overall.

American Heart Association↗

PubMed1999

[Television publicity and food preferences of school age children of the metropolitan region].

BACKGROUND: There is an alarming increase in the prevalence of child obesity in Chile. Lack of exercise and bad feeding habits strongly strongly contribute to the problem. AIM: To investigate the influence of television publicity on school age children food preferences. MATERIAL AND METHODS: A semi structured interview was applied to a representative sample of 786 school age children aged 6 to 11 years old, living in Metropolitan Santiago. Time watching television during week days and the attitude towards food and beverage commercials was analyzed and related to food preferences. RESULTS: Ninety nine percent of school age children watch television during week days and 20% watches more the three hours daily. Snack commercials such as those about potato chips, chocolates, cookies and ice cream, are preferred by 35% of children. Soda commercials are preferred by 33% and yoghurt commercials by 12%. Eighty five percent of children had money to buy food. Of these, 66% bought snacks, 15% bought sodas and 7% yoghurt. The same tendency was observed in school collations. CONCLUSIONS: The high percentage of children, watching television and the influence of commercials in their food preferences, requires an urgent educational strategy to promote healthy feeding habits.

Adolescent↗

PubMed1986

Increased dopamine metabolism in the nucleus accumbens and striatum following consumption of a nutritive meal but not a palatable non-nutritive saccharin solution.

This study examined the concentrations of dopamine (DA) and its metabolites homovanillic acid (HVA) and 3,4-dihydroxyphenylacetic acid (DOPAC) in the striatum and nucleus accumbens of rats that were either 20 hr food deprived or had been given 1 hr of access to food pellets, a liquid diet, or a palatable 0.4% saccharin solution. Significant increases were observed in the HVA/DA ratio in both structures following ingestion of either liquid diet or food pellets. Increases in the DOPAC/DA ratio were observed only after the ingestion of liquid diet. Ingestion of saccharin solution had no effect on any index of DA activity. These results indicate that the type of food ingested can influence dopaminergic responses to feeding, and argue against an exclusive role for motor or reward processes in determining DA activity.

3,4-Dihydroxyphenylacetic Acid↗

PubMed2005

Factors determining the nutrition transition in two Mediterranean islands: Sardinia and Malta.

OBJECTIVE: To examine and analyse consumption changes over time of 24 food items between Sardinia and Malta. SETTING: The data were collected in 2001 in Sardinia and 2002 in Malta. DESIGN: A structured qualitative questionnaire, articulated around four main themes: food supply, transformation, preparation and consumption habits, was administered by face-to-face interviews with the help of a local person. It encompassed mainly open-ended questions, which allowed us to measure factors contributing to change. SUBJECTS: Thirty mother-daughter pairs were interviewed in each insular territory. RESULTS: Despite a common trend revealing a shift away from cereals, pulses and potatoes to the benefit of meat products, fats and sugar, our results showed contrasting evolutions in food consumption between both insular societies. Fruit and vegetables, olive oil and fish, which are part of the main features of the Mediterranean diet, were among the top foods for which consumption frequency has increased in Sardinia. In Malta, besides an increase in olive oil and vegetable consumption, cheeses and desserts showed the highest increase. Along with modernity and improved living conditions, enhanced commercial availability and increased diversity of food preparation were also identified as factors contributing to food consumption changes. CONCLUSIONS: Although the Sardo-Mediterranean model is evolving under the impact of modernisation, it is not disappearing. In Malta, however, modernity has led to a more sudden shift from a state of food shortage to one of affluence, but in a cultural context where the identity is no longer Mediterranean but Anglo-Saxon.

Adult↗

PubMed2004

[Food allergy: effect of proteins-lipids and proteins-polysaccharides interactions].

The most widely used ingredients in food formulation are proteins, lipids and polysaccharides. Proteins-lipids and proteins-polysaccharides interactions play a key role in the structure, stability, sensorial and nutritional properties of formulated foods. The objective of the present study is to highlight the importance of proteins-lipids and proteins-polysaccharides interactions, on the immuno-reactivity of allergenic proteins. Two models have been studied, on the one hand refined and not refined oils (soya and sunflower) and soya lecithin, on the other hand mixtures based on peanut proteins and polysaccharides (arabic gum, pectin, xylan). STUDY OF OILS: We have extracted proteins, using a PBS buffer, from refined and not refined oils from soya, sunflower and from soya lecithin, determined protein concentrations and identified allergenic proteins using SDS-PAGE electrophoresis and immuno-blotting. Phospholipids are determined by atomic absorption spectrometry. The protein determination and SDS-PAGE show the presence of a higher amount of proteins in not refined oils and lecithin as compared to refined oils. An important amount of proteins associated to phospholipids are eliminated by degumming on the form of lecithin. On the other hand, residual proteins from refined oils are accompanied by phospholipids. Immuno-blots reveal the presence of a 56 kDa allergen in oils issued from soya seeds and soya lecithin, and the presence of a 67 kDa allergen in oils issued from sunflower seeds. We conclude that the presence or elimination of proteins, especially allergens from oils is linked to amphiphilic association to phospholipids. STUDY OF PEANUT PROTEINS-POLYSACCHARIDES MIXTURES: We have digested in vitro proteins in a dialysis bag using a multi-enzymatic method and characterized proteins and peptides using SDS-PAGE electrophoresis and immuno-blotting. Our results confirm that peanut proteins alone are digested by proteases and that a number of large peptides still have epitopes recognized by anti-peanut proteins antibodies. Our results also show that the presence of polysaccharides changes the peptidic profile after digestion and that, depending on the polysaccharide type, smaller or larger peptides can be obtained in the dialysis bag. Smaller peptides are obtained using pectin whereas larger peptides are obtained using arabic gum and xylan. In the latter case, an increasing amount of peptides reacts to antibodies. Our first observations clearly show the need to better understand modifications of proteins allergenicity induced by the presence of other ingredients such as polysaccharides and lipids, in relation to technological treatments.

Allergens↗

PubMed1975

Food for all.

Ensuring food for all requires an interdisciplinary approach, an evaluation of all sectors of the economy and the formulation of objectives which include proper nutrition in overall development plans. It is my contention that the introduction of nutrition priorities at this level, complemented with the traditional immediate and short-term measures of food aid, nutrition programmes, health campaigns and nutrition education will do much to alleviate the world's food problems. Priorities must be defined, planning structures strengthened, and politicians convinced that objectives can be reached. Otherwise, meagre resources will continue to give low priority to agriculture and social reform and we will have accomplished little toward our objective of food for all.

Agriculture↗

PubMed2003

The present and future organisation of Veterinary Services in Asia: the examples of the Republic of Korea and Japan.

The Veterinary Services of the Republic of Korea and Japan are reviewed and summarised. To cope with ever-increasing demands on Veterinary Services, both countries have made continued efforts to expand the services, which currently only have a limited number of government personnel. To overcome some of the problems associated with international trade, e.g. outbreaks of foot and mouth disease and classical swine fever (hog cholera), the authorities of the Republic of Korea are considering strengthening quarantine services by combining the National Veterinary Research and Quarantine Service and the National Plant Quarantine Service of the Ministry of Agriculture and Forestry (MAF). In the field of veterinary public health services, the Republic of Korea and Japan have different organisational structures. All Veterinary Services, including veterinary public health, are kept within the MAF in the Republic of Korea, whereas in Japan, the Ministry of Agriculture, Forestry and Fisheries (MAFF) deals with general animal production and health services and the Ministry of Health, Labour and Welfare (MHLW) deals with the safety of animal products, food poisoning and the prevention/control of zoonoses, such as rabies and Q fever. In Japan, after the occurrence of bovine spongiform encephalopathy in 2001, the authorities undertook a thorough review of the Veterinary Services, focusing particularly on food safety. A reorganisation of the administrative structure was proposed, and will be completed by the end of 2003. Subject to the approval of the Diet (House of Councillors), an independent 'Food Safety Commission' will be created within the cabinet office which will undertake risk analyses related to foods, and risk management will be carried out by the relevant ministry, i.e. the MAFF or the MHLW. The Animal Health Division of the MAFF will also be moved from the Livestock Industry Department to a new 'Consumer Safety Department' of the MAFF, where additional responsibilities in fish health control and feed safety control will be assumed.

Commerce↗

PubMed2004

Allergy assessment of foods or ingredients derived from biotechnology, gene-modified organisms, or novel foods.

The introduction of novel proteins into foods carries a risk of eliciting allergic reactions in individuals sensitive to the introduced protein and a risk of sensitizing susceptible individuals. No single predictive test exists to perform a hazard assessment in relation to allergenic properties of newly expressed proteins in gene-modified organisms (GMOs). Instead, performance of a weighted risk analysis based on the decision tree approach has been suggested. The individual steps of this analysis comprise sequence homology to known allergens, specific or targeted serum screens for immunoglobulin E (IgE) cross-reactions to known allergens, digestability studies of the proteins in simulated gastric and/or intestinal fluids, and animal studies. These steps are discussed and five examples of risk evaluation of GMOs or novel foods are presented. These include ice-structuring protein derived from fish, microbial transglutaminase, GMO-soybeans, amylase and the Nangai nut.

Allergens↗

PubMed2001

Redox state, reactive oxygen species and adaptive growth in colonial hydroids.

Colonial metazoans often encrust surfaces over which the food supply varies in time or space. In such an environment, adaptive colony development entails adjusting the timing and spacing of feeding structures and gastrovascular connections to correspond to this variable food supply. To investigate the possibility of such adaptive growth, within-colony differential feeding experiments were carried out using the hydroid Podocoryna carnea. Indeed, such colonies strongly exhibited adaptive growth, developing dense arrays of polyps (feeding structures) and gastrovascular connections in areas that were fed relative to areas that were starved, and this effect became more consistent over time. To investigate mechanisms of signaling between the food supply and colony development, measurements were taken of metabolic parameters that have been implicated in signal transduction in other systems, particularly redox state and levels of reactive oxygen species. Utilizing fluorescence microscopy of P. carnea cells in vivo, simultaneous measurements of redox state [using NAD(P)H] and hydrogen peroxide (using 2',7'-dichlorofluorescin diacetate) were taken. Both measures focused on polyp epitheliomuscular cells, since these exhibit the greatest metabolic activity. Colonies 3-5h after feeding were relatively oxidized, with low levels of peroxide, while colonies 24h after feeding were relatively reduced, with high levels of peroxide. The functional role of polyps in feeding and generating gastrovascular flow probably produced this dichotomy. Polyps 3-5h after feeding contract maximally, and this metabolic demand probably shifts the redox state in the direction of oxidation and diminishes levels of reactive oxygen species. In contrast, 24h after feeding, polyps are quiescent, and this lack of metabolic demand probably shifts the redox state in the direction of reduction and increases levels of reactive oxygen species. Within-colony differential feeding experiments were carried out on colonies 24h after the usual, colony-wide feeding. At this time, a single polyp was fed, and this polyp was compared with an otherwise similar polyp from the same colony. A pattern similar to the whole-colony experiments was obtained: the just-fed polyp, as it begins contracting shortly after feeding, appears to be relatively oxidized, with low levels of peroxide compared with the polyp that was not fed. These data are consistent with the hypothesis that adaptive colony development in response to a variable food supply is mediated by redox state or reactive oxygen species or both, although alternative hypotheses are also discussed.

Adaptation, Physiological↗