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The effects of chronic ventromedial hypothalamic stimulation on weight gain in rats.

The effects of chronic stimulation of the ventromedial hypothalamus and adjacent structures on body weight, food intake, and epididymal fat pad weight were examined in normophagic rats. Three hours of intermittent low level electrical stimulation were delivered three times per week for four weeks; body weight and food intake were monitored for an additional ten days after stimulation trials had ceased. Animals receiving ventromedial hypothalamic stimulation had the shallowest growth curves while stimulation of other structures produced a rate of growth that fell between that of the ventromedial hypothalamic and the implanted control group. This pattern persisted during the poststimulation phase. Food intake, while initially depressed in the stimulated groups, began to approach control levels by the third week of stimulation. Efficiency of food utilization (weight gain/consumption) was significantly reduced during the first week of stimulation in the ventromedial hypothalamic stimulated group. Fat pad weight was slightly decreased in this group as well. These findings suggest that chronic stimulation of the ventromedial hypothalamus causes a persistent shift in metabolic rate that results in a long-term inhibition of weight gain.

Adipose Tissue↗

[Atherogenic trans isomers of fatty acids in some food products].

OBJECTIVE: Trans isomers of fatty acids (TFA) contain double bonds in their molecular structure with the trans configuration. Food products prominent for their TFA content include plant oils (margarine), mayonnaise, products baked with plant oils, and ready-made glazes and icings. The so-called fast foods and snacks (bars, chips) represent a significant source of TFA, particularly for children and youth. Considering the potentially atherogenic properties of TFA, this work was undertaken to determine the content of the principal monounsaturated TFA in some food products ubiquitous on the market, i.e. margarines and snacks. MATERIAL AND METHODS: We studied bars (Snickers, Mars, Twix), chips (Lay's, Snack, Cheetos), and margarines (Rama Classic, Rama Olivio, Vita, Flora, Finea, Delma, Masmix, Krówka, Smakowita with butter, Extra Pomorskie). The content of TFA was determined with gas chromatography. RESULTS: The highest content ofmonounsatured TFA among sweets was disclosed for the Twix bar (2.94 microg/g), while the lowest for Snickers (0.3 microg/g). Among margarines, the highest content of TFA was found for Smakowita with butter (87.6 microg/g), Krówka (46 microg/g), and Vita (38.7 microg/g), whereas the content was lowest in Finea (0.12 microg/g) and Delma (0.14 microg/g). In the case of chips, the content was highest for Cheetos (3.5 microg/g) and lowest for Snack (0.09 microg/g). CONCLUSIONS: The content of atherogenic TFA in common food products varies widely. In some cases, the content of TFA is considerable and unjustly undisclosed by manufacturers. Promotion of these products should include information in respect of TFA. This conclusion is of particular importance considering the significance of these products in the diet of children and youth.

Adolescent↗

Contractile properties and histochemical characteristics of the rat diaphragm after prolonged triamcinolone treatment and nutritional deprivation.

The influence of decreased muscle mass and reduced food intake on diaphragm structure and contractility in male Wistar rats was determined after triamcinolone acetate treatment (TR: 0.5 mg per kg per day for 4 weeks) and two degrees of undernutrition (PW: pair-weight, which resulted in a similar (41%) reduction of body weight as TR; PF: pair-fed, which resulted in a moderate (13%) reduction of body weight) and a free-fed control group (FF, with an increase (9%) in body weight). energy intake of TR decreased, but based on daily measurements of food intake and body weight, energy expenditure of the TR rats was increased compared with the other groups. Body (BW) and muscle weights were reduced in proportion to the extent of undernutrition in the nutritionally deprived rates (i.e. BW and diaphragm weight of PF animals were reduced 215 and 16% respectively compared with FF, v. a. 48% and 41% reduction in the PW group). Triamcinolone-induced atrophy was limited to type II fibres (30% of type IIa and 45% of type IIx/b, p < 0.05), while severe chronic undernutrition (PW) induced a generalized fibre type atrophy in the diaphragm (23% type I, 38% type IIa and 49% type IIx/b, p < 0.05), and moderate undernutrition (PF) caused only significant type IIa atrophy (20%, p < 0.05). A leftward shift of the diaphragmatic tension-frequency relationship and a decreased fatiguability of the TR and PW bundles were observed (p < 0.01), while the PF bundles were not significantly different compared with FF. These results suggest that triamcinolone and severe undernutrition cause similar alterations in in vitro contractility of the diaphragm. The effects of triamcinolone treatment on diaphragm structure may be partly explained by the reduced food intake, but the atrophy pattern induced by severe undernutrition (PW) was different.

Age Factors↗

The cost of catching up: increased winter mortality following structural growth compensation in the wild.

Although laboratory and observational studies suggest that many animals are capable of compensatory growth after periods of food shortage, few field experiments have demonstrated structural growth compensation in the wild. Here, we addressed the hypotheses that (i) food restriction can induce structural compensatory growth in free-living animals, (ii) that compensation is proportional to the level of body size retardation and (iii) that compensation induces mortality costs. To test these, wild brown trout (Salmo trutta) yearlings were brought to the lab, tagged individually, subjected to four levels of food deprivation (including a control), released back into the native stream and recaptured after one, five and ten months. Brown trout fully restored condition and partially restored mass within a month, whereas compensation in structure (i.e. body length) was not evident until after five months, supporting hypothesis 1. As the level of growth compensation was similar among the three deprived groups, hypothesis 2 was not supported. A final recapture after winter revealed delayed mortality, apparently induced by the compensatory response in the deprived groups, which is consistent with hypothesis 3. To our knowledge, this is the first field experiment demonstrating structural compensatory growth and associated costs in a wild animal population.

Animals↗

Circumoral movements in response to three different food textures in children 6 months to 2 years of age.

The purpose of this study was to establish an objective description of circumoral behavior in normal children during the oral phase of ingestion. The response to three different food textures--solid, viscous, and puree--was examined in 143 healthy children aged 6 months to 2 years. Feeding sessions were videotaped and data analyzed using criteria for describing circumoral structures during anticipation of food, removal of food from a spoon, as well as the initiation of chewing and swallowing. As children get older their feeding behaviors mature, which is characterized by better lip control, increased mobility of the tongue, and decreased involvement of the circumoral structures in swallowing. These data are intended for clinicians who evaluate young children with feeding impairments in order to determine children's functional age level.

Child Development↗

Food borne infection by a Norwalk like virus (small round structured virus).

Two outbreaks of gastrointestinal illness with identical symptoms occurred in parties attending banquets on consecutive evenings at a large hotel. The illness was typical of epidemic winter vomiting disease. Small round structured viruses resembling those seen in the Norwalk Ohio outbreak were identified by electron microscopy in stools of victims from one episode. One food handler was found to be excreting the virus, and there was evidence of a poor standard of hygiene in the kitchen. A food history analysis showed the illness to be significantly associated with eating cold cooked ham.

Disease Outbreaks↗

Central administration of resistin promotes short-term satiety in rats.

OBJECTIVE: Several hormones expressed in white adipose tissue influence food intake at the central level. We sought to determine whether resistin, a circulating adipose-derived hormone in rodents, has actions on the hypothalamus by determining the effects of central resistin injection on food intake and on hypothalamic Fos protein expression. DESIGN: As resistin expression in adipose tissue is influenced by altered nutritional status, we studied the effect of central resistin in both fed and pre-fasted rats. RESULTS: In fasted rats, central injection of resistin decreased food intake acutely and increased the number of cells that express Fos protein in the arcuate nucleus but not in any other hypothalamic structure. The effect on food intake was dose-dependent and did not result in the formation of a conditioned taste aversion. CONCLUSIONS: Taken together, these results provide the first evidence documenting a central action of resistin, which could be involved in a feedback loop targeting the hypothalamus. On the other hand, since we observed resistin mRNA in the arcuate and ventromedial nuclei of the hypothalamus, it is also possible that brain-derived resistin serves as a neuropeptide involved in the regulation of energy homeostasis. However, since resistin-induced satiety was modest and transient, as central administration for several days did not affect body weight, the physiological relevance and therapeutic potential of the observed principal phenomenon may be limited.

Adiponectin↗

[Food-borne outbreak of gastroenteritis caused by small round structured virus. 2. An outbreak associated with bakery product consumption].

In December 1989, an outbreak of gastroenteritis associated with cake consumption occurred in a day-care center with 60 children and 12 staff in Saitama prefecture. Children were served cakes at the Christmas party held in the day-care center and ate them with their families. Thirty-three of the 59 children (56%), 16 of the 74 families (22%) and 1 of the 10 staff (10%) eating the cakes became ill. Illness consisted primarily of nausea, vomiting, diarrhea and fever; the median incubation period was 31 hours. Bacteriological analysis of stool specimens did not reveal a causative agent. Small round structured viruses (SRSV) were detected in fecal specimens from 10 of the 17 ill children (59%) and 2 of the 6 ill families (33%) by electron microscopy. Cakes were purchased from a bakery where an employee who prepared the cake denied symptoms, and SRSV was not detected in the fecal specimen from the employee. Thus, it was not determined that the cake was contaminated by a food handler.

Adolescent↗

[Stereochemical structure of d-borneol in "the Japanese Standards of Food Additives"].

d-Borneol is shown at "The Japanese Standards of Food Additives" the sixth edition. Though the absolute stereochemistry of this compound is described as 1S, 2R-form, the opposite optical rotation for the same structure is described in other literatures. The application of improved Mosher's method to d-borneol resulted in 1R, 2S-form for its absolute stereochemistry.

Camphanes↗

Kinematics of the buccal mass during swallowing based on magnetic resonance imaging in intact, behaving Aplysia californica.

A novel magnetic resonance imaging interface has been developed that makes it possible to image movements in intact, freely moving subjects. We have used this interface to image the internal structures of the feeding apparatus (i.e. the buccal mass) of the marine mollusc Aplysia californica. The temporal and spatial resolution of the resulting images is sufficient to describe the kinematics of specific muscles of the buccal mass and the internal movements of the main structures responsible for grasping food, the radula and the odontophore. These observations suggest that a previously undescribed feature on the anterior margin of the odontophore, a fluid-filled structure that we term the prow, may aid in opening the jaw lumen early in protraction. Radular closing during swallowing occurs near the peak of protraction as the radular stalk is pushed rapidly out of the odontophore. Retraction of the odontophore is enhanced by the closure of the lumen of the jaws on the elongated odontophore, causing the odontophore to rotate rapidly towards the esophagus. Radular opening occurs after the peak of retraction and without the active contraction of the protractor muscle 12 and is due, in part, to the movement of the radular stalk into the odontophore. The large variability between responses also suggests that the great flexibility of swallowing responses may be due to variability in neural control and in the biomechanics of the ingested food and to the inherent flexibility of the buccal mass.

Animals↗

Reflections about the functional potential of legume proteins. A review.

The term "functional potential" was introduced to better approach to the understanding of the relationships between the structure and the functional properties of food proteins. Although in practice the complex of structural features of a protein contributes to its functionality, it is very useful to regard the functional potential of the protein surface on the one side and to look on special effects of protein conformation (role of compact or unfolded state) on the functionality on the other side. This point of view may help to design the best strategy of modification of the protein structure and functionality. The special situation of the oligomeric legume storage protein, i.e. legumin-like 11 S globulins and vicilin-like 7 S globulin, and the structural and functional modification of 11 S globulin by limited tryptic hydrolysis and by acylation are discussed in this paper.

Fabaceae↗

Opisthobranchia (Mollusca, Gastropoda) - more than just slimy slugs. Shell reduction and its implications on defence and foraging.

BACKGROUND: In general shell-less slugs are considered to be slimy animals with a rather dull appearance and a pest to garden plants. But marine slugs usually are beautifully coloured animals belonging to the less-known Opisthobranchia. They are characterized by a large array of interesting biological phenomena, usually related to foraging and/or defence. In this paper our knowledge of shell reduction, correlated with the evolution of different defensive and foraging strategies is reviewed, and new results on histology of different glandular systems are included. RESULTS: Based on a phylogeny obtained by morphological and histological data, the parallel reduction of the shell within the different groups is outlined. Major food sources are given and glandular structures are described as possible defensive structures in the external epithelia, and as internal glands. CONCLUSION: According to phylogenetic analyses, the reduction of the shell correlates with the evolution of defensive strategies. Many different kinds of defence structures, like cleptocnides, mantle dermal formations (MDFs), and acid glands, are only present in shell-less slugs. In several cases, it is not clear whether the defensive devices were a prerequisite for the reduction of the shell, or reduction occurred before. Reduction of the shell and acquisition of different defensive structures had an implication on exploration of new food sources and therefore likely enhanced adaptive radiation of several groups.

Journal Article↗

Pollen-food syndromes associated with weed pollinosis: an update from the molecular point of view.

Pollinosis patients often display adverse reactions upon the ingestion of plant-derived foods as a result of immunoglobulin E (IgE) cross-reactive structures shared by pollen and food allergen sources. The symptoms of such pollen-food syndromes (PFS) or class 2 food allergies range from local oral allergy syndrome to severe systemic anaphylaxis. Two clinical syndromes, the celery-mugwort-spice syndrome and the mugwort-mustard-allergy syndrome have been described in association with weed pollinosis. However, other associations between weed pollinosis and hypersensitivity to certain kinds of food have also been observed, like the mugwort-peach, the ragweed-melon-banana, the plantain-melon, the pellitory-pistachio, the goosefoot-fruit, the Russian thistle-saffron, and the hop-celery association. The number of allergen sources involved, the allergens, and influencing factors including geography, diet, and food preparation contribute to the high clinical complexity of PFS. So far, known causative cross-reactive allergens include profilins, lipid transfer proteins, and high-molecular weight allergens and/or glycoallergens. The current usage of nonstandardized allergen extracts poses additional problems for both diagnosis and therapy of PFS patients. Further identification and characterization of involved allergens is inescapable for better understanding of PFS and vaccine development. Panels of recombinant allergens and/or hypo-allergens are promising tools to improve both PFS diagnostics and therapy.

Allergens↗

Species positions and extinction dynamics in simple food webs.

Recent investigations on the structure of complex networks have provided interesting results for ecologists. Being inspired by these studies, we analyse a well-defined set of small model food webs. The extinction probability caused by internal Lotka-Volterra dynamics is compared to the position of species. Simulations have revealed that some global properties of these food webs (e.g. the homogeneity of connectedness) and the positions of species therein (e.g. interaction pattern) make them prone to modelled biotic extinction caused by population dynamical effects. We found that: (a) homogeneity in the connectedness structure increases the probability of extinction events; (b) in addition to the number of interactions, their orientations also influence the future of species in a web. Since species in characteristic network positions are prone to extinction, results could also be interpreted as describing the properties of preferred states of food webs during community assembly. Our results may contribute to understanding the intimate relationship between pattern and process in ecology.

Animals↗

Self-administered food frequency questionnaire used in the 5-year follow-up survey of the JPHC Study: questionnaire structure, computation algorithms, and area-based mean intake.

In this section we described the structure of the self-administered semiquantitative food frequency questionnaire used in the 5-year follow-up survey of the JPHC study, the computation algorithms, and the area-based mean intakes of nutrients and food groups in the subjects of the validation study. The FFQ consists of five sections: 1) semiquantitative frequency questions for rice and miso (fermented soybean paste)-soup, 2) those for alcoholic beverages, 3) those for vitamin supplements, 4) those for foods and beverages, and 5) questions on dietary and cooking behaviors. From the questions, intakes of nutrients and foods by food groups were computed. Although most of them were computed from the frequency and relative portion size indicated in the replies, together with the fixed portion size, a seasonal coefficient was added in the computation of vegetables and fruits. Only frequency of intake and fixed portion size were used for computation of beverages. Sugar and cream added in coffee and tea were computed from the frequency of coffee and tea intake. The intakes of cooking oil, cooking salt (sodium), and salt in noodle-soup were estimated from the questions of relative preference of oil, salt, and noodle-soup.

Algorithms↗

Personal food systems of male college hockey players.

This study sought to improve the understanding of processes involved in food choice and dietary change by examining how members of a college men's ice hockey team experienced the multiple factors influencing their food choices. The study employed a theory-guided, grounded-theory approach, participant observation, and open-ended interviews with ten team members. Field notes and transcripts were analysed using the constant comparative method. Going to college and playing hockey involved adjusting to new food and athletic environments, increased personal responsibility for food choices, and new meanings for food and eating. Players viewed hockey, health, and taste as major determinants of their food practices. Hockey meant structured schedules, a social network, and performance expectations. Health meant "feeling good" for hockey, having a lean body composition, and a desirable body image. Low-fat foods were viewed generally as healthy, but as not providing taste satisfaction or reward. Players' food practices cycled through four phases over the year according to the changing meanings and importance of hockey, health, and taste. The findings advance the concept of personal food system to represent the way that a person constructs the options, barriers, trade-offs, rules, and routines in food choice in response to how s/he views his/her relationships with food and the environment.

Adolescent↗

Deep brain stimulation for chronic pain: results of two multicenter trials and a structured review.

OBJECTIVES: A U.S. Food and Drug Administration ruling required clinical trials to evaluate the safety and efficacy of deep brain stimulation devices, thereby limiting treatment to the investigational setting. INTRODUCTION: As an investigator in two clinical trials of deep brain stimulation, I sought to determine why pain remained an unapproved indication despite regulatory approval of the same device for tremor. METHODS: The results of two multicenter trials of deep brain stimulation for pain were analyzed, and the pertinent literature was reviewed using published guidelines for the evaluation of clinical trial reports. RESULTS: The first-generation Model 3380 lead trial enrolled 196 patients; the current Model 3387 trial enrolled 50 patients. Prospectively defined criteria for success included at least half of patients reporting >/=50% pain relief at 1 year. Manufacture of the Model 3380 lead was discontinued, and the 3387 trial closed early because of slow enrollment, high attrition, and low efficacy. When results were analyzed according to the study plan, neither trial was successful. Consequently, deep brain stimulation has not been approved for pain control by the U.S. Food and Drug Administration. CONCLUSIONS: Deep brain stimulation has not been shown to produce effective long-term pain relief. Future studies of motor cortex stimulation and similar therapies will require appropriate control groups and accepted methods of data collection and analysis to support claims that predictable and reliable analgesic effects are produced in humans.

Journal Article↗

Women on the short end of the loaf: intrahousehold food allocation among members of poor Nepalese families.

Intensive and structure intrahousehold observations of the pattern of food allocation in poor rural Nepalese households indicate no difference in the distribution of nutrients between male and female children. In contrast, preferential food distribution patterns among adults show that women are less likely to achieve recommended levels of some nutrients than are men of the same age.

Family↗