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PubMed2001

Identity, traceability, acceptability and substantial equivalence of food.

The numerous food crises that Europe has experienced during the past five years have raised new consumer demands concerning the characterization, traceability, and safety of foods which are proposed on the market. The consumer has, at the same time, vigorously placed into question the modes of agricultural production in industrialized countries, as well as the structures and means of evaluating the food risks and the conditions of the consumer's participation in the public debate in these domains. For certain groups of consumers, one also attends a contestation of the expertise and the application to the food domain of the considerable progress that has taken place in the field of biotechnology. So it is that the development of genetically modified organisms (mainly plants, the raw material of food products) has experienced a slowing down in the European Union. The answers afforded to these new exigencies of consumers in matter of identity, traceability, and acceptability of the foods are dealt with in this paper, as well as the elements which may concur with the evaluation of their safety. The positive role that biotechnology can afford to the different domains is emphasized. A source of uneasiness, biotechnology is also a powerful tool for ameliorating the evaluation of the sanitary risks and for answering the hopes of the citizen in the food domain.

Animals↗
PubMed1990

The effect of a nutrition education programme 'learning by teaching' on the dietary attitudes of a group of adolescents.

The purpose of this study was (1) to examine the structure of attitudes towards healthy food in a group of adolescents and (2) to evaluate the impact of a health education programme on these attitudes. The strategy used was to make 14-year-old schoolchildren learn about nutrition and dental health by teaching these topics to 10-year-old children. A pre-test/post-test non-equivalent control group design was used. The experimental group consisted of four classes of 14-year-old children from two schools and the reference group of four classes of the same age from two comparable schools. The data were collected prior to, immediately after, and, for the experimental group, two months after the implementation of the programme. Factor analysis revealed three dimensions of attitudes: PROHEALTH, TASTE, and SIGNIFICANT OTHERS. Analysis of covariance with pre-test measures as covariates showed a significant effect of the programme on PROHEALTH, no effect on TASTE, and a significant study group by gender interaction effect on SIGNIFICANT OTHERS, which, however, was impaired two months later. It is concluded that the change in attitudes can be explained by two mechanisms: dissonance arousal and discrepancy between personal attitudes and group norms; and that future programmes should emphasise affection rather than cognition.

Adolescent↗
PubMed1989

[Effects of thymosin and B-activin on lateralization of sensomotor control in rats].

Characteristics of regulatory effects of B-activin and thymosin (fraction 5) on the activity of right and left hemispheres were studied in rats. The results obtained were estimated basing on the analysis of the following components of food-searching behavior: lateralization of a single conditioned-reflex response; preference of right or left paw; spontaneous rotations. Opposite effects of thymosin and B-activin were found at different stages of the food-searching behavior. Thymosin activated structures of the left hemisphere. A conclusion is made on the possibility of application of these drugs for targeted influencing the balance of intra-hemispheric activity in the brain functional pathology and during the compensatory process.

Activins↗
PubMed1994

Hygiene behaviour practises as discriminants for the occurrence of childhood diarrhoea.

Structured observations of events during food preparation, feeding and defeacation management were conducted in four rural Nigerian communities as part of a longitudinal study aimed at identifying environmental and behavioural risk factors for diarrhoea. A discriminant analysis model was developed for distinguishing between children who had no diarrhoea and those who had diarrhoea during the study period. The behavioural practises associated with occurrence of diarrhoea included disposal of faeces around the house; careless handling of cleaning material; use of feeding bottles; purchase of cooked food from food vendors; and the presence of domestic animals in food preparation places. Using age and defeacation scores as discriminants, the sensitivity of the discriminant model was 73% its specificity 68%, while 71% of cases were correctly classified.

Case-Control Studies↗
PubMed1996

Outbreaks of foodborne viral gastroenteritis in England and Wales: 1992 to 1994.

Outbreaks of foodborne viral gastroenteritis in England and Wales from 1992 to 1994 have been analysed using data from the national surveillance scheme for general outbreaks of infectious intestinal disease. The cause was virologically confirmed for 389 (31%) of the 1280 outbreaks for which a minimum set of data were collected. Forty-seven of the 389 were attributed to foodborne transmission, 41 of which were caused by small round structured viruses (SRSV). An infected food handler was suspected to be a contributing factor in 14 and the consumption of oysters in eight of these 41 foodborne SRSV outbreaks. No seasonal pattern emerged. The highest incidences occurred in Wales, West Midlands, and South Western regional health authorities. The annual rate of outbreaks did not increase during the three year period (Chi square for linear trend 0.6; p = 0.4). Much remains to be discovered about the epidemiology of foodborne viruses, and outbreaks present an opportunity to enhance our knowledge. As molecular diagnostic techniques become routinely available, it is likely that the role of viruses in foodborne outbreaks will be increasingly recognised.

Data Collection↗
PubMed1997

[Functional properties of dietary fiber. Mechanisms of action in the gastrointestinal tract].

Physiological effects of dietary fiber (DF) are the result of complex interacting mechanisms between the components of food which is not digested by the endogenous enzymes of the digestive tract and the conditions of gastrointestinal environment, such as pH, ionic strength and other food components. Chemical nature and structure of each component of DF are two factor that determine their behaviour in lumen intestinal. This article report the main functional properties of DF and explain how these are responsible of physiological effects developed by DF in gastrointestinal tract.

Dietary Fiber↗
PubMed2004

What makes a food protein an allergen?

Food allergens are almost always proteins, but not all food proteins are allergens. This one statement sums up the purpose of this article, defining the difference between an innocuous food protein and a food allergen. The simplest answer is that a food allergen has the ability to first elicit an IgE response, and then, on subsequent exposures, to elicit a clinical response to the same or similar protein. However, this simplistic answer avoids the more complex issues of defining the biochemical characteristics that allow a food protein to survive the extremes of food processing, escape the digestive enzymes of the human gastrointestinal tract, and interact with the immune system. More than 700 allergen sequences have been identified from food and nonfood sources. However, despite increasing knowledge of the structure and amino acid sequences of the identified allergens, only a few biochemical characteristics can be associated with food allergens. Food allergen characteristics, including abundance of the protein in the food; multiple, linear IgE binding epitopes; resistance of the protein to digestion and processing; and allergen structure are discussed, and the possible reasons they predispose some food proteins to become allergens are suggested.

Allergens↗
PubMed1987

Misclassification of nutrient intake of individuals and groups using one-, two-, three-, and seven-day food records.

In this study, 6,844 food records were collected during three years (1979-1982) from 106 volunteer Wisconsin women, aged 35-65 years. Subjects recorded all intake of food, and vitamin/mineral supplements on a structured, precoded form. One-, two-, three-, and seven-day records were compared with usual intake of calcium, kilocalories, vitamin A, and vitamin C. Usual intake was calculated using 37-72 food records per subject. Estimates of group means from a small number of records were not significantly different from mean usual intake (p greater than 0.05). Correlations with usual intake ranged from 0.43-0.64 and from 0.71-0.90 for the one day and the seven-day estimates, respectively. For the one-day record, 43-67% of subjects were correctly classified to the extreme quintiles of intake, 52-76% for the seven-day record. Classification was least good for vitamin A, better for other nutrients with lower intraindividual variance. However, overall agreement with usual classification of assignment to quintiles even with the seven-day record was less than 55% for all four nutrients. Effects at extremes of intake might be more easily analyzed than dose-response relations.

Adult↗
PubMed2004

Food allergy and non-allergic food hypersensitivity in children and adolescents.

BACKGROUND: Previous studies have shown a 10-fold discrepancy of self-reported food-induced symptoms and physician-diagnosed food hypersensitivity. Little information is available on the prevalence of food hypersensitivity in unselected paediatric populations. No data were available for German children. OBJECTIVE: To study the perception of food-induced symptoms in the paediatric population, to investigate the allergens accused, to objectify patients' reports, and to identify subgroups at risk of having food-induced allergy (FA) or non-allergic food hypersensitivity (NAFH) reactions. METHODS: This paper presents the data of the paediatric group (0-17 years) of a representative, randomly sampled, cross-sectional population-based survey studying 13 300 inhabitants of the German capital city Berlin regarding food-related symptoms. Instruments included mailed questionnaires, structured telephone interviews, physical examination, skin-prick tests, specific serum IgE and standardized, controlled and blinded oral food challenges. RESULTS: Two thousand three hundred and fifty-four individuals were contacted by mailed questionnaire, 739 (31.4%) responses could be fully evaluated. Four hundred and fifty-five (61.5%) participants reported symptoms related to food ingestion, 284 (38.4%) affirmed reproducible symptoms in the standardized telephone interview. One hundred and eighty-four (24.8%) individuals were fully examined. Reproducible symptoms to food were found in 31 (4.2%) children and adolescents: 26 (3.5%) showed symptoms of FA and five (0.7%) of NAFH. The oral allergy syndrome was most often observed. Foods most commonly identified by oral challenges were apple, hazelnut, soy, kiwi, carrot and wheat. CONCLUSION: The perception of food-related symptoms is common among children and adolescents from the general population. Self-reports could be confirmed in around one out of 10 individuals, still resulting in 4.2% of proven clinical symptoms. However, most reactions were mild and mainly because of pollen-associated FA, while NAFH reactions were less common. Severe IgE-mediated FA was observed in individuals with pre-existing atopic disease, who should be fully investigated for clinically relevant FA.

Adolescent↗
PubMed1980

[Modification of light-evoked potentials depending on the feeding behavior of rabbits. I. Dependence on motivational state].

Flash evoked potentials (EP) from visual cortex, dorsal hippocampus, and other brain structures were recorded during various behavioral situations in freely moving rabbits. The aim of the study was to investigate the direction and rate of EP-changes after a two-day food deprivation. Potentials evoked during slow wave sleep had not shown any systematical changes after the food deprivation. Considerable changes, almost synchronously in different structures, were observed during an active food expectance in a pseudoconditioning experiment in contrast to the hungry sleep state. Prominent was a significant reduction in peak latency and amplitude of the primary components, a massive positivation (surface negativation) in the early section of the potentials (30-100 ms), a depression of the late negative complex in visual cortex and the appearance of early components in the sensomotory cortex. Our results show that outside the typically motivational centers a short food deprivation causes changes in evoked neuronal activity only during a certain motivational level. Considering similar EP-configurations in otherwise motivated wakefulness, the participation of nonspecific and also motivational specific mechanisms of activation is discussed.

Animals↗
PubMed2003

Honeybee (Apis mellifera L.) mrjp gene family: computational analysis of putative promoters and genomic structure of mrjp1, the gene coding for the most abundant protein of larval food.

Mrjp1 gene belongs to the honeybee mrjp gene family encoding the major royal jelly proteins (MRJPs), secreted by nurse bees into the royal jelly. In this study, we have isolated the genomic clone containing the entire mrjp1 gene and determined its sequence. The mrjp1 gene sequence spans over 3038 bp and contains six exons separated by five introns. Seven mismatches between the mrjp1 gene sequence and two previously independently published cDNA sequences were found, but these differences do not lead to any change in the deduced amino acid sequence of MRJP1. With the aid of inverse polymerase chain reaction we obtained sequences flanking the 5' ends of other mrjp genes (mrjp2, mrjp3, mrjp4 and mrjp5). Putative promoters were predicted upstream of all mrjp genes (including mrjp1). The predicted promoters contain the TATA motif (TATATATT), highly conserved both in sequence and position. Ultraspiracle (USP) transcription factor (TF) binding sites in putative promoter regions and clusters of dead ringer TF binding sites upstream of these promoters were predicted computationally. We propose that USP, as a juvenile hormone (JH) binding TF, might possibly act as a mediator of mrjp expression in response to JH. Mrjp1's genomic locus is predicted to encode an antisense transcript, partially overlapping with five mrjp1 exons and entirely overlapping with the putative promoter and predicted transcriptional start point of mrjp1. This finding may shed light on the mechanisms of regulation of mrjps expression. Southern blot analysis of genomic DNA revealed that all so far known members of mrjp gene family (mrjp1, mrjp2, mrjp3, mrjp4 and mrjp5) are present as single-copy genes per haploid honeybee genome. Although MRJPs and the yellow protein of Drosophila melanogaster share a certain degree of similarity in aa sequence and although it has been shown that they share a common evolutionary origin, neither structural similarities in the gene organization, nor significant similarities between intron sequences of mrjp1 gene and fourteen yellow-like genes of D. melanogaster were found.

Animals↗
PubMed2005

Interaction strength combinations and the overfishing of a marine food web.

The stability of ecological communities largely depends on the strength of interactions between predators and their prey. Here we show that these interaction strengths are structured nonrandomly in a large Caribbean marine food web. Specifically, the cooccurrence of strong interactions on two consecutive levels of food chains occurs less frequently than expected by chance. Even when they occur, these strongly interacting chains are accompanied by strong omnivory more often than expected by chance. By using a food web model, we show that these interaction strength combinations reduce the likelihood of trophic cascades after the overfishing of top predators. However, fishing selectively removes predators that are overrepresented in strongly interacting chains. Hence, the potential for strong community-wide effects remains a threat.

Animals↗
PubMed2005

The meaning of food to breast cancer survivors.

Although a definitive relationship between diet and breast cancer remains controversial, many women adopt dietary change after diagnosis. To understand factors motivating dietary change, we explored the meanings that breast cancer survivors attached to food during recovery. Six women who were breast cancer survivors for six to 19 years participated in semi-structured interviews exploring personal meanings attached to food, dietary changes after diagnosis, factors influencing dietary change, and experiences with food in relation to breast cancer. Two distinct phases emerged. These corresponded to active treatment, when women used food to gain control, to cope, for comfort, and for hope, and to post-treatment, when the meanings that women attached to food were shaped by the perception of food's role in breast cancer causation. Women who believed that diet prevents a first diagnosis adopted change to prevent recurrence, while those who did not believe in the relationship between diet and breast cancer adopted change to improve health. In women with breast cancer, food can be an important coping mechanism. Women may benefit from counselling grounded in the meanings they attach to food over the recovery continuum.

Adaptation, Psychological↗
PubMed2000

Toxic lactonic lipopeptide from food poisoning isolates of Bacillus licheniformis.

Toxins from three Bacillus licheniformis strains connected to a fatal food poisoning were isolated and their structures elucidated. Toxins were purified from methanol extracts of the B. licheniformis biomass using boar sperm cells as the toxicity indicator. The HPLC purified toxins showed protonated masses m/z 1007, 1021 and 1035 in MALDI-TOF-MS. The toxins isolated from the strains of different origins contained the same three components of which and each had a same amino-acid residues L-Gln, L-Leu, D-Leu, L-Val, L-Asp, D-Leu and L-Ile in that order. Toxins were identified as lichenysin A, a cyclic lactonic heptalipopeptide in which the main 3-hydroxy fatty acids are 13-15 carbons in length. We showed that the toxins from food and food poisoning isolates of B. licheniformis were identical to lichenysin A both in the structure and in the toxic symptoms induced to boar spermatozoa. Confocal laser scanning microscopy showed that the acrosome and the plasma membrane of boar spermatozoa were the targets of lichenysin A toxicity.

Amino Acid Sequence↗
PubMed2005

Methane production and microbial community structure in single-stage batch and sequential batch systems anaerobically co-digesting food waste and biosolids.

Anaerobic co-digestion of food waste and biosolids was carried out in sequential batch and single-stage batch systems in four treatments. Methane yield, which was used as a functional process parameter, differed between treatments, with the single-stage batch system generating lower volumes than the sequential batch systems. Volatile fatty acid (VFA) concentrations and pH in the leachate also differed between treatments. VFA concentrations were highest and methane generation yields lowest in the single-stage batch system in comparison to the sequential batch systems. The anaerobic microbial community structure of the domains Archaea and Bacteria, determined by denaturing gradient gel electrophoresis, differed between treatments and was correlated to a number of environmental parameters such as pH, VFA concentration and methane generation rate. Methane generation rate was significantly correlated to the community structure of Bacteria but not Archaea. This indicated that the substrates that are produced by acetogens (Bacteria) are important for the growth and community structure of the methanogens (Archaea). Community structure of Archaea changed over time, but this had no observable effect on functional ability based on methane yields. Microbial diversity (H') was shown to be not important in developing a functionally successful anaerobic microbial community.

Anaerobiosis↗
PubMedDate not supplied

[The structure and cytophysiology of the endocrinocytes of the gastric epithelium in a disordered food regimen].

By means of the light and electron microscopic methods the differentiation and the genesis of the epithelium endocrinocytes of the stomach mucous membrane were studied in the albino rats, fasted for 72-144 hours. The deprivation of food is followed by the increase of the number of endocrinocytes and by the change of their ultrastructure. The latter demonstrates the delay of the elimination of the secretory material in some cells (ECL, G, D, D1 cells) while the active functional condition was found in the others (ECL, A-like cells). Exo-endocrine cells with the EC or A-type granules are found in the epithelium, which is regarded as a mechanism aimed at the increase of the number of the appropriate (ECL or A-type of endocrinocytes, participating in the general metabolism of the organism.

Animals↗