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PubMed1986

[Effect of mass communication media in food purchasing at the family level].

The main purpose of this study was to determine the effect of mass media advertisement of food products (TV, radio and the press), particularly in pre-school and school-age children, as well as the concomitant impact these age groups have on the family food buying patterns. To test the hypothesis that the impact of mass media advertising on foods varied in the different socioeconomic levels of a community, a stratified sample of all children below 13 years of age, who attended the Francisco Fajardo school in the central coast of Venezuela, was drawn. Mass media contact, food and nutrition knowledge and other socioeconomic characteristics were related to the family's food-buying patterns. More specifically, the age, working status and educational level of the mother in regard to beliefs concerning the nutritional value of advertized food products, were related. A semi-structured questionnaire was designed, tested and applied to the housewife or whoever performed this role within the family. Findings revealed that families of low socioeconomic status are prone to be most influenced by mass media food product advertising. This is reflected not only in food purchasing practices but also in food consumption patterns at the family level. Chocolate drinks, cereals, jello, sausages, and ice cream are the most popular products among pre-school and school-aged children, without social class distinction. Furthermore, results revealed that the degree of exposure to mass communication media--television, radio and newspapers--is a determining factor in children's food preferences at all socioeconomic levels, and that television is the media exerting the greatest influence.

Advertising↗

PubMed1991

[Analysis of food and feed by partial sequences of characteristic protein components (carrier peptides). 1. Isolation and structural determination of wheat-specific peptides from chymotryptic hydrolysates of gliadin].

Gliadins from wheat flour were extracted with 70% aqueous ethanol and hydrolyzed with alpha-chymotrypsin. Eight peptides, which seemed adequate as specific indicators for wheat ('Leitpeptide'), were isolated from the partial hydrolysate by RP-HPLC and analyzed for their amino acid sequences. Six of them were attributed to gliadin sequences already described in the literature, whereas two peptides represented novel sequence variations. Parallel investigations on the corresponding partial hydrolysates of prolamins from rye, barley, oats and maize showed that the isolated peptides were specific for wheat. A search in the protein data bank MIPS X (as of January 23 rd, 1990) did not produce any identical sequence. The 'Leitpeptide' allows the sensitive and specific recognition of wheat in complex and heated systems by RP-HPLC. They could be used also as the basis for immunochemical tests which would be convenient in routine analysis.

Amino Acid Sequence↗

PubMed2001

The structure of a pyoverdine produced by a Pseudomonas tolaasii-like isolate.

Cultures of Agaricus bisporus, the most extensively cultivated mushroom, can be infected severely by Pseudomonas tolaasii. This pathogen is characterized by the so-called white line reaction, a precipitate formed on agar plates between its colonies and those of P. reactans, both belonging to the collective species P. fluorescens. A recent study has shown that a group of P. tolaasii isolates can be subdivided into two groups or 'siderovars', based on the pyoverdines they produce (Munsch et al. 2000). One group of strains is characterized by the pyoverdine described by Demange et al. (1990). A representative of the second group (strain Ps3a) was found to produce the same pyoverdine as a strain which had been classified before as P. aureofaciens. However, based mainly on 16S rRNA gene sequence comparisons and REP-PCR generated fingerprints, the two strains are not identical. They are also distinguishable from the P. tolaasii type strain.

Agaricales↗

PubMedDate not supplied

[Subcortical structures of the brain and the behavior of white rats].

Conditioned food and defensive reflexes have been studied in white rats following bilateral injury of paleo-, archi-, neostriatum, substantia nigra and paleocortex. It has been shown that these deep structures play a role in the operational memory of animals.

Amygdala↗

PubMed2004

Diaquabis(pyridine-2-carboxamide-kappa2N1,O2)nickel(II) disaccharinate tetrahydrate.

In the crystal structure of the title compound, [Ni(C6H6N2O)2(H2O)2](C7H4NO3S)2.4H2O or [Ni(pia)2(H2O)2](sac)2.4H2O (pia is picolinamide or pyridine-2-carboxamide, and sac is the saccharinate anion), the Ni2+ cation, located on a centre of symmetry, is coordinated by two symmetry-related aqua ligands together with a pair of symmetry-related bidentate pia molecules and exhibits a distorted octahedral environment. The unique unligated sac anion in the asymmetric unit resides on a general position and has a single negative charge. The coordinated water molecules link the sac ions to the metal complex via O-H...O hydrogen bonds. In addition, the sac ions are linked to the metal complex via intermolecular pi-pi interactions between the benzene ring of the sac ion and the pyridine ring of a pia ligand. Each uncoordinated water molecule is hydrogen bonded to sac moieties through O-H...O and O-H...N hydrogen bonds.

Crystallography, X-Ray↗

PubMed2001

Extended quantitative structure-activity relationships for 80 aromatic and heterocyclic amines: structural, electronic, and hydropathic factors affecting mutagenic potency.

The mutagenic/carcinogenic heterocyclic amines formed during the cooking of protein foods have been determined to be probable or possible human carcinogens. As part of a comprehensive study of the food mutagens, our laboratory has produced a series of quantitative structure-activity relationships (QSARs) of aromatic and heterocyclic amines, to attempt to elucidate the mechanisms of mutagenesis/carcinogenesis. Amines are genotoxically active only after activation by a series of reactions converting the parent compound to an electrophilic derivative, which is postulated to be a nitrenium ion that covalently binds to and damages DNA. An important agent in this conversion is cytochrome P450. In this report we develop a QSAR for 80 amines of diverse structure and a range of 10 orders of magnitude in mutagenic potency. New structural factors and quantum chemical ab initio and Hückel calculations are included. The results are interpreted to show that a main determinant of mutagenic potency is the extent of the aromatic pi-electron system. Small contributions are made by both the dipole moment and the calculated stability of the nitrenium ion. Multiple linear regression models account for nearly two-thirds of the variance in potency, leaving room for additional unknown factors. The role of cytochrome P450 1A in amine toxification is supported, and further theoretical and experimental research on its reaction mechanisms and modeling of its active site are proposed.

Amines↗

PubMed1997

[Unsaturated fatty acids omega-3. I. Structure, sources, determination, metabolism in the organism].

Fats covered approximately 22% of energy requirements in diets of ancient human being, and simultaneously the value of ratio of polyunsaturated fatty acids (PUFA) to saturated (SFA) was estimated as 1.4 and the proportion of PUFA omega 6 to PUFA omega 3 was 1:1. During the last twenty thousands years the composition of human diets was changing dramatically due to economical, culture and social changes. However, there are indicators that the ratio of PUFA omega 6 to PUFA omega 3 in human diet was unchanging until beginning of XIX century. Dramatic technological breakthrough in food technology during last 100 years caused radical changes in the structure and quality of food consumption. It is estimated that at present fats cover about 40% of energy requirements in diets of people in developed countries, and the value of ratio of dietary PUFA omega 6 to PUFA omega 3 is 25:1 and even 50:1. Epidemiological nutritional studies indicate that in populations which consume inadequate amount of PUFA omega 3 most often occur the disorders on atherosclerotic and immunological background as compared to populations which consume diets with appropriate covering the requirements of dietary PUFA omega 3. Therefore, it could be supposed that increased occurrence so-called civilization disorders is the result of increased consumption of highly manufactured food with changed composition (and also to increased fats consumption and decreased consumption of PUFA omega 3). This hypothesis is confirmed by the observations that the supplementation of diets with PUFA omega 3 gives the desirable results in the treatment of many disorders. The main objective of this two parts paper is to characterize the polyunsaturated fatty acids, their metabolic path ways as well as the possibilities of the use of the diet supplementation with PUFA omega 3 in the treatment and prophylaxis of some metabolic disorders. The structure, sources, determination and pathways in organism are discussed in part I, and the role of eicosanoids originating from respective PUFA omega 3 and advantages of the supplementation the diet with PUFA are discussed in part II.

Animals↗

PubMedDate not supplied

[The endocannabinoid system and food intake control].

Acylethanolamides are endogenous compounds with lipid structure including anandamide (AEA), palmitoilethanolamide, oleylamide and oleylethanolamide (OEA). AEA binds to the cannabinoid receptor CB1, located at the central nervous system, while OEA is an endogenous ligand for the alpha subtype of peroxisome-proliferator activating receptor (PPARalpha). Since AEA acts on the same receptor which binds marihuana active derivatives, this group of compounds were called endocannabinoids. Besides typical central effects of cannabinoids, CB1 receptor activation leads to hyperphagia, whereas its pharmacological blockade is followed by changes in energy metabolism favouring substrate oxidation. OEA has inhibitory effects on food intake by acting on PPARalpha receptors which modulate the autonomous nervous system. Both acylethanolamides, AEA and OEA, have opposite effects suggesting that they form part of a satiety sensor system. Whereas fasting triggers AEA release and inhibits OEA synthesis, eating has the reverse effect. Additionally OEA is also produced by adipocytes ad has some effects on lipid metabolism. All these data suggest a role for acylethanolamides and the endocannabinoid system in the pathophysiology of obesity, diabetes and atherosclerosis.

Adipocytes↗

PubMed2000

What is the cost of a healthy diet in terms of achieving RDAs?

OBJECTIVE: Assessing how the Italian average food pattern would be affected in terms of consumption structure and expenditure by the adoption of nutritional prescriptions. DESIGN: A linear programming model with nutritional and food habits constraints was employed to generate a pattern following recommended daily allowances (RDAs) and nutritional guidelines provided for the Italian population. SETTING: Food consumption data from ISTAT Household Budget Survey of Italian population. SUBJECTS: Italian families investigated by the Family Budget Survey of the National Institute of Statistics. RESULTS: Compared to actual behaviour, the pattern generated by the model implies an increased consumption of vegetables, pasta, rice and fresh fish, and a decreased consumption of meats, bread, sugars and cakes, and especially fats and oils. At given prices, total expenditure is lower than actual expenditure. CONCLUSIONS: Differences between actual behaviour and the generated pattern are consistent with long-term trends in food consumption. The adoption of RDAs is unlikely to result in an increased food expenditure.

Budgets↗

PubMed1974

Central trigeminal structures and the lateral hypothalamic syndrome in the rat.

Extrahypothalamic lesions of central trigeminal structures produce a syndrome of aphagia, adipsia, finickiness, and food spillage. The similarity of these effects to the lateral hypothalamic syndrome and the location of trigeminal structures within the diencephalon suggest that some components of the lateral hypothalamic syndrome are due to incidental damage to trigeminal fibers of passage.

Animals↗

PubMed2005

Allergenic proteins in soybean: processing and reduction of P34 allergenicity.

Soybean ranks among the "big 8" of the most allergenic foods, and with increasing consumption of soybean products, the incidence of soy-caused allergies is expected to escalate. Soybean and its derivatives have become ubiquitous in vegetarian and many meat-based food products, and as a result, dietary avoidance has become difficult. However, soybeans can be manipulated in a variety of ways to alter their allergenicity. Several studies have focused on reducing the allergenicity of soybeans by changing the structure of the immunodominant allergen P34 using food processing, agronomic, or genetic manipulation techniques. A review of the literature pertaining to these studies is presented here.

Allergens↗

PubMedDate not supplied

[The origin of parasitism in trombiculid mites (Acariformes: Trombiculidae)].

On the basis of literary data and original investigations some phylogenetic, ecological and morphological aspects of the origin of parasitism in trombiculid mites are carefully considered for the first time. It is shown that parasitism in this group of trombidiform mites is a relatively young historical phenomenon and was formed after their ontogenesis had differentiated into active and quiescent stages. Therefore, in the life pattern of trombiculid mites the character of individual development, that defines their biotopical restriction, is much more important than the phase parasitism. Primitive organization of the digestive system and extraintestinal digestion, so characteristic of this group, are one of the main reasons of the origin of their parasitism. Under pasture conditions trombiculid mites, that initially were predators-entomophages with bite-sucking mouth parts, pass easily to parasitism on vertebrate animals and become primary lymphophages. They use the vertebrate host's organism exclusively as a source of food and by the extent of polyphagia are very close to free-living blood-sucking insects. Stylostome, that develops during feeding of trombiculid larvae and some other closely related groups of trombidiform mites, is a universal structure for achieving a large amount of food on a wide range of animals during a relatively short period of time and reflects wide host-parasite specificity of these parasitic mites. From the historical view the larvae of trombiculid mites did not pass from one group of hosts to the others, but owing to morphological preadaptation to parasitism passed in a definite historical period, not earlier than Paleogene, to parasitism on all classes of terrestrial vertebrates, especially on mammals, their primary hosts.

Animals↗

PubMed1992

[Role of the frontal cortex in the organization of rapid ballistic movements of rats].

Rapid ballistic food-getting movement characteristics were studied in albino rats. After ablation of the second area of the frontal cortex contralaterally as to the preferred extremity the number of attempts increased and their duration with reorganization of the phase structure of movements decreased. The habit of food extraction was lost after bilateral ablation of the cortex. The obtained results have illustrated significance of the frontal cortex in formation and realization of moving programmes.

Animals↗

PubMed1999

Heterocyclic amine formation and the impact of structure on their mutagenicity.

The occurrence and formation of heterocyclic amines in foods is discussed in light of the consistent finding of a new class of imidazopyridines. In addition, a quantitative structure-activity relationship will be presented correlating the potency of these imidazopyridines to predicted chemical properties. Although no strong linear correlation is found between the potency and the chemical properties, a low dipole moment is found to be a qualitative predictor of high mutagenic potency.

Imidazoles↗

PubMed1997

Storage effect on dentine structure and on resultant composite bond strengths.

This study evaluates the effects of a food simulating solution (75 vol% ethanol/water) and an artificial saliva (Moi-Stir) on dentine structure and chemistry, using scanning electron microscopic examination and Fourier transform infra-red (FTIR) microscopic characterization. The effect on the bonding of composites to the conditioned dentine were evaluated by shear bond strength (SBS) tests. Three adhesive/composite systems were examined: Tenure/Marathon One, Scotchbond Multi-Purpose/Z100, and Optibond/Herculite XRV. Control specimens were stored in either distilled water or tested without storage. Dentine surface exposure to ethanol resulted in partial loss of the smear layer and of plugs, as well as possible perturbation of collagen. Dentine surfaces exposed to artificial saliva or to distilled water had no evidence of any change from normal appearance of the smear layer. The measured FTIR spectra for most specimens conditioned in these two liquids appeared to be similar to those obtained from fresh dentine. SBS data were analysed using ANOVA and the Tukey LSD test. The SBS value for the non-preconditioned control (23.0 +/- 3.7 MPa) or for the dentine preconditioned in distilled water (22.9 +/- 4.2 MPa) was significantly higher (P < 0.05) than that for dentine pre-conditioned in ethanol (20.0 +/- 3.5 MPa). The SBS (13.3 +/- 3.4 MPa) of all bonding systems was reduced by 40-50% (P < 0.001) when artificial saliva pre-conditioned dentine was used. The failure mode at the dentine-bonding agent interface for the artificial saliva group was adhesive in nature. This is in contrast to the complex cohesive fracture mode found in the control groups and in most ethanol conditioned groups. Dentine structure and chemistry, shear bond strength, and the subsequent debonded mode can be significantly affected by exposure to oral environment prior to conditioning.

Adhesiveness↗

PubMedDate not supplied

Occurrence, identification, and bacterial mutagenicity of heterocyclic amines in cooked food.

Potent mutagenic activity in Salmonella bacteria has been reported in cooked foods in numerous laboratories worldwide. Determining the human risk from exposure to these biologically active compounds in our diet requires genotoxic and carcinogenic evaluation of the chemicals coupled with determination of the dose consumed. Thus, knowledge of the exact structure of the mutagens present in the food and enough synthesized material for biological assessment are essential for this evaluation. To reach this goal, isolation of these compounds requires the Ames/Salmonella assay to guide the purification and identification process. Mass and NMR spectrometry are used to identify the isolated compounds. Finally, these findings are followed by synthesis of the exact isomer. The predominant class of mutagens found in cooked foods of the western diet are amino-imidazo-quinoxalines, amino-imidazo-pyridines and amino-imidazo-quinolines, collectively called amino-imidazoazaarenes (AIAs). Mass amounts of these specific compounds range from less than 1 to 70 ng/g of meat. The mutagens are formed from the heating of natural precursors (creatinine, amino acids, and possibly sugars) in the food. These AIAs are some of the most potent mutagens ever tested in Salmonella bacteria with the number and position of methyl groups having an important influence on the mutagenic activity.

Amines↗

PubMed1994

Sweeter future with fewer sugars.

Britain's food industry is entering a new phase. For as far ahead as we can see, manufacturers will be creating an expanding, ever more complex range of reduced sugar and sugar-free products. These innovations will vastly strengthen the structural approach to oral health promotion: improving food as well as educating people.

Beverages↗

PubMed2003

Relationship of gender and eating disorder symptoms to reported cravings for food: construct validation of state and trait craving questionnaires in Spanish.

Using confirmatory factor analysis, we cross-validated the factor structures of the Spanish versions of the State and Trait Food Cravings Questionnaires (FCQ-S and FCQ-T; ) in a sample of 304 Spanish college students. Controlling for eating disorder symptoms and food deprivation, scores on the FCQ-T were higher for women than for men, but no sex differences were observed on the FCQ-S. Eating disorder symptomatology was predictive of trait cravings, whereas food deprivation was predictive state cravings. Trait cravings, but not state cravings, were more strongly associated to symptoms of anorexia and bulimia nervosa than with other psychopathology. We suggest that cravings can be conceptualized as multidimensional motivational states and that our data support the hypothesis that food cravings are strongly associated with symptoms of bulimia nervosa.

Adolescent↗