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PubMed2004

Toxicity of trans-nonachlor to Sprague-Dawley rats in a 90-day feeding study.

The chlordane constituent trans-nonachlor and its metabolite oxychlordane are among the most persistent chlordane-related contaminants and are found in tissues and milk from humans ingesting diets high in Arctic marine mammal fat. Although chlordane is no longer registered in North America, there is a need for toxicological data on chlordane-related contaminants found in food and the environment which are either structurally different or relatively more abundant than the constituents of the original chlordane mixture. Thus, a feeding study was undertaken to provide toxicological data on trans-nonachlor. Male and female Sprague-Dawley rats were exposed to 0, 5, 13 or 50 ppm trans-nonachlor in feed for 90 days and clinical, hematological and histopathological changes were assessed in each rat. Female rats were less able than males to metabolize and eliminate trans-nonachlor and, as a result, accumulated more trans-nonachlor in their adipose tissues. trans-Nonachlor, like technical chlordane and other organochlorines, induced liver microsomal enzymes in a pattern similar to phenobarbital. Endocrine effects included functional and morphological changes in the thyroid and adrenals. In male rats exposure to trans-nonachlor was associated with changes in endpoints indicative of increased oxidative stress, which may be related to both direct action on cellular targets or to secondary effects resulting from cytochrome P450 induction. The results indicate that subchronic trans-nonachlor exposure in rats induced hepatic changes with far-reaching metabolic and endocrine effects. Differences in target organ responses in male and female rats indicate that the sex-related metabolic differences affecting trans-nonachlor bioaccumulation and elimination merit further study.

Adipose Tissue↗
PubMed2006

Thermal stability of beta-lactoglobulin in the presence of aqueous solution of alcohols and polyols.

A systematic study concerning the effect of aqueous solution of alcohols and polyols with four carbon atoms on beta-lactoglobulin stability is presented. The protein was chosen due to its functional properties and applications in food and pharmaceutical industries and because its structure and properties in aqueous solution have been widely described. The alcohols having a four carbon chain were selected to examine the effect of the gradual increase in the number of OH groups on protein stability. Protein thermal stability in water, buffers and dilute aqueous solutions of 1-butanol, 1,2-butanediol, 1,2,4-butanetriol and 1,2,3,4-butanetetrol was evaluated by fluorescence spectroscopy. The results were used to determine the temperature range in which the unfolding process is reversible and the protein denaturation temperature in acetate buffer pH 5.5 and in the aqueous mixed solvents. Thermodynamic results show that alcohol denaturating effect diminishes gradually as the number of OH groups increase.

Alcohols↗
PubMed2004

Social organization in the cat: a modern understanding.

An increasing body of research work has made it clear that, while Felis catus can survive in the solitary state, social groups with an internal structure, are formed whenever there are sufficient food resources to support them. Most people who have cats have two or more cats. Failure to understand what will promote either friendly or aggressive behavior can lead to various behavior problems, including aggression and conflict over resources, such as food, resting sites and litterboxes. An understanding of the natural social organization, relationships and communication between cats is therefore essential, and is the subject of this paper.

Animals↗
PubMed2002

Orofacial mechanoreceptors in humans: encoding characteristics and responses during natural orofacial behaviors.

We used microneurography to characterize stimulus-encoding properties of low-threshold mechanoreceptive afferents in human orofacial tissues. Signals were recorded from single afferents in the infraorbital, lingual and inferior alveolar nerves while localized, controlled, mechanical stimuli were delivered to the facial skin, lips, oral mucosa and teeth. We likewise analyzed activity in these afferents during orofacial behaviors such as speech, chewing and biting. The afferents in the soft tissues functionally resemble four types described in the human hand: hair follicle afferents, slowly adapting (SA) type I and type II afferents and fast adapting (FA) type I afferents. Afferents in the facial skin, lips and buccal mucosa respond not only to contact with environmental objects, but also to contact between the lips, changes in air pressure generated for speech sounds, and to facial skin and mucosa deformations that accompany lip and jaw movements associated with chewing and swallowing. Hence, in addition to exteroceptive information, these afferents provide proprioceptive information. In contrast, afferents terminating superficially in the tongue do not signal proprioceptive information about tongue movements in this manner. They only respond when the receptive field is brought into contact with other intraoral structures or objects, e.g. the teeth or food. All human periodontal afferents adapt slowly to maintained tooth loads. Populations of periodontal afferents encode information about both which teeth are loaded and the direction of forces applied to individual teeth. Most afferents exhibit a markedly curved relationship between discharge rate and force amplitude, featuring the highest sensitivity to changes in tooth load at low forces (below 1 N). Accordingly, periodontal afferents efficiently encode tooth load when subjects first contact, hold, and gently manipulate food by the teeth. In contrast, only a minority of the afferents encodes the rapid and strong force increase generated when biting through food. We conclude, that humans use periodontal afferent signals to control jaw actions associated with intraoral manipulation of food rather than exertion of jaw power actions.

Behavior↗
PubMed1998

Stories of meaning: lay perspectives on the origin and management of noninsulin dependent diabetes mellitus among older women in the United States.

Researchers have sought to explain nonadherence to standard medical regimens by investigating a variety of sociodemographic variables, and, less often, by exploring variations between the health perspectives and life circumstances of the individual. While divergence between lay and professional perspectives on the etiology and treatment of chronic diseases, such as noninsulin dependent diabetes mellitus, may possibly account for the documented low rates of adherence to biomedical recommendations, health beliefs and activities are best understood as connected to an individual's personal history and circumstances. In order to evaluate the relationship between causal explanation of NIDDM and adherence, ethnographic interviews were conducted among 51 older (65+) women with diabetes and their physicians. We chose to investigate adherence to dietary recommendations because it represents one of the most challenging lifestyle modifications and is particularly important to maintaining glycemic control. The interviews involved ethnomedical and food frequency intake questionnaires and semi-structured interviews. Results reveal a stronger association between dietary adherence and etiological perspectives on diabetes than any sociodemographic factors, including ethnicity, education and income or other health belief factors. Informants suggested five categories that they believed were responsible for the onset of their NIDDM; poor past dietary practices (n = 22); familial tendency to have diabetes (n = 10); improper bodily functioning (n = 10); personal risk factors (n = 6); and currently being overweight (n = 3). Analyses indicated that those who implicate former dietary practices, currently being overweight, or having improper bodily functions were more likely to follow a standard recommended diet for individuals with diabetes. These findings also highlight the attempt by individuals with NIDDM to create 'stories' of meaning of their diabetes by linking their current management strategies for NIDDM with past practices and history. In addition, our results question the utility of the 'biomedical/alternative' labels.

Aged↗
PubMed1999

The emergence of the concept of a tool in food-retrieving behavior of the ants Formica japonica Motschulsky.

We propose a weak definition for the usage of a tool for an ethological study of ants. In particular, we illustrate the usage of a cart in experiments on the transportation of foods by ants as employing a logical structure including a contradiction. The contradiction originates in ruling out the very term 'tool' from the description of the behavior of the animals. Focusing on a self-similar structure underlying the description of a contradiction, we observe a particular time-series sequence of ants' behaviors following a 1/f or Zipf's law. The behaviors following the 1/f or Zipf's law manifest an appropriateness of the notion of a cart as a logical jump.

Animals↗
PubMed2003

Fasting is a physiological stimulus of vagus-mediated enhancement of nociception in the female rat.

The vagus nerve modulates nociception by a mechanism dependent upon gonadal hormones and the adrenal medulla. In the present study we tested the hypothesis that this modulation is dynamically controlled by physiological stimulation of structures innervated by the subdiaphragmatic vagus. Specifically, food deprivation (fasting) was employed to increase activity in the subdiaphragmatic vagus, and the experiments were performed mainly in female rats because our previous observations suggested that baseline activity in the pathway is lower in females than in males. Consistent with the hypothesis, after a 48-h fast, female rats exhibited increased nociceptive behavior in the formalin test. In contrast, fasting had no effect on formalin-evoked nociceptive behavior in male rats. The fasting-induced effect on nociception appears to be mediated by the vagus nerve since it is prevented by subdiaphragmatic vagotomy. Also similar to the previously characterized vagus-mediated modulation, the effect of fasting in the female is blocked by gonadectomy or adrenal medullectomy, and hormone replacement with 17beta-estradiol in gonadectomized female rats restored the effect of fasting. Decreased glucose metabolism apparently does not play a significant role in the effect of fasting on nociception, since the effect was unchanged when 5% glucose was provided in the drinking water throughout the fasting period. On the other hand, increasing the bulk content of the stomach (without providing nutrients) by infusion of petrolatum significantly attenuated the effect of fasting during the interphase period of the formalin response, suggesting that decreased gut distention, and possibly motility, are important in fasting-induced enhancement of nociception. These results indicate that fasting is a physiological activator of the vagus-mediated pain modulation pathway. This suggests the possibility that, especially in females, natural periodic changes in gut distention and motility may control an ongoing vagus-mediated adjustment in the organism's nociceptive sensitivity.

Adrenal Medulla↗
PubMed2006

New constituents of sweet Capsicum annuum L. fruits and evaluation of their biological activity.

Four new acyclic diterpene glycosides named capsianosides (1-4), together with 12 known compounds, were isolated from the fresh sweet pepper fruits of Capsicum annuum L., a plant used as a vegetable food, spice, and external medicine. The chemical structures of new natural compounds, as well as their absolute configurations, were established by means of spectroscopic data including infrared, high-resolution mass spectrometry, and one- and two-dimensional nuclear magnetic resonance and by chemical derivatization. The known capsidiol (11) showed bacteriostatic properties in vitro against Helicobacter pylori with a minimum inhibitory concentration (MIC) of 200 microg/mL when compared with the commercial drug metronidazole (MIC, 250 microg/mL). Some purified components were also tested for their antioxidant activities.

Anti-Bacterial Agents↗
PubMed2004

A novel carbon skeletal trichothecane, tenuipesine A, isolated from an entomopathogenic fungus, Paecilomyces tenuipes.

Tenuipesine A (1), a novel trichothecane with an unprecedented carbon-migrated skeleton that embodies of a cyclopropane ring, was isolated from cultivated fruiting bodies of Paecilomyces tenuipes (Isaria japonica), a popular entomopathogenic fungi employed in folk medicine and health foods in China, Korea, and Japan. The structure was determined on the basis of two-dimensional NMR data. Its stereochemistry was elucidated by spectroscopic data and the chemical transformation of the coexisting trichothecene, 4beta-acetoxy-12,13-epoxytrichothec-9-ene-3alpha,15-diol (2). [structure: see text]

Cyclopropanes↗
PubMed2002

Enzyme polymorphisms in Rhizoglyphus robini and R. echinopus and their application in paternity analysis.

Cellulose acetate electrophoresis (CAE) was used to investigate enzyme polymorphism in two congeneric species of Acaridae, Rhizoglyphus robini and R. echinopus. Using homogenates of individual mites, 27 enzymes were examined in two buffers. Five enzymes showed interspecific polymorphism, 15 exhibited intraspecific variation in R. robini and 12 in R. echinopus. Polymorphic PGDH was used to analyse paternity in progeny of R. robini females that had mated with two males. The second male sired on average 67% of progeny. Enzyme polymorphism can be used to study poorly known aspects of acarid mites biology, such as their mating systems and population structure under natural conditions and in stored foods.

Acaridae↗
PubMed2005

The subthalamic nucleus exerts opposite control on cocaine and 'natural' rewards.

A challenge in treating drug addicts is preventing their pathological motivation for the drug without impairing their general affective state toward natural reinforcers. Here we have shown that discrete lesions of the subthalamic nucleus greatly decreased the motivation of rats for cocaine while increasing it for food reward. The subthalamic nucleus, a key structure controlling basal ganglia outputs, is therefore able to oppositely modulate the effect of 'natural' rewards and drugs of abuse on behavior. Modulating the activity of the subthalamic nucleus might prove to be a new target for the treatment of cocaine addiction.

Animals↗
PubMed2003

Subgrouping in obesity based on Rorschach personality characteristics.

Conceptual (a priori) subgroups in obesity based on personality findings from the Rorschach Comprehensive System were suggested for 100 obese patients. The subgroups were further compared in terms of general anamnestic and behavioral data. The largest subgroup was Rorschach characterized by difficulties with emotions and a tendency towards depression. Demographic and behavioral data for this subgroup revealed intermediate or higher education, regular meals, eating disorders like binge eating, periodic variations in eating during the year and experiencing body size as having a psychological meaning. The other subgroup was characterized by coping liabilities and was further associated with a lower socio-economic level and irregular or chaotic meal patterns. For the group with emotional difficulties, the results suggest a more complex psychological pattern, where eating and emotions could be closely related. The group with coping liabilities could have difficulties other than emotional ones concerning food and eating, such as finding a structure for eating and making changes in lifestyle and habits.

Adaptation, Psychological↗
PubMed1999

The mycotoxin fumonisin B1 transcriptionally activates the p21 promoter through a cis-acting element containing two Sp1 binding sites.

Fumonisin B1 (FB1) is a food-borne mycotoxin produced by Fusarium moniliforme. Structurally FB1 resembles sphingoid bases, and ingestion of FB1 causes several animal diseases. FB1 will cause hepatic carcinoma in rats and is implicated as a cofactor in esophageal or hepatic carcinoma. Previous studies concluded that FB1 repressed cyclin-dependent kinase 2 (CDK2) activity but induced CDK inhibitors p21(Waf1/Cip1), p27(Kip1), and p57(Kip2) in monkey kidney cells (CV-1). In contrast, CV-1 cells transformed by simian virus 40 are resistant to the antiproliferative or apoptotic effects of FB1. Consequently, FB1 treatment of CV-1 cells leads to cell cycle arrest and apoptosis. In this study, we demonstrate that FB1 transcriptionally activates the p21 promoter. Functional analysis of the p21 promoter by reporter gene assays mapped the FB1-responsive region to -124 to -47. DNase I footprinting analysis revealed two protected motifs that span the FB1-responsive region, -124 to -101 (footprint II) and -89 to -67 (footprint III). Further studies demonstrated that DNA sequences from -124 to -101 were sufficient for FB1 stimulation. DNA sequences from -124 to -101 contain two Sp1 binding sites, and gel shift assays provided evidence that nuclear factors specifically bind to this region. Disruption of the two Sp1 binding sites abrogated the binding of nuclear proteins and prevented activation by FB1. Taken together, these results suggest that Sp1 or Sp1-related proteins mediate FB1-induced activation of the p21 promoter.

Animals↗
PubMed2003

Plasmodium falciparum falcilysin: a metalloprotease with dual specificity.

The malaria parasite Plasmodium falciparum degrades host cell hemoglobin within an acidic food vacuole. The metalloprotease falcilysin has previously been identified as an important component of this catabolic process. Using random peptide substrate analysis, we confirm that recombinant falcilysin is highly active at acidic pH, consistent with its role in hemoglobin degradation. Unexpectedly, the enzyme is also robustly active at neutral pH, but with a substantially different substrate specificity. Imaging studies confirm the location of falcilysin in the food vacuole and reveal association with vesicular structures elsewhere within the parasite. These data suggest that falcilysin may have an expanded role beyond globin catabolism and may function as two different proteases in its two locations.

Animals↗
PubMed2006

Differential effects of 4 types of environmental enrichment on aggressive pecking, feather pecking, feather loss, food wastage and productivity in Japanese quail.

1. We examined the effects of 4 types of environmental enrichment (foraging opportunities, structural complexity, sensory stimulation/novelty, and social companionship) on aggressive and feather pecking, feather condition, food wastage, body weight, feed conversion, and egg production in adult Japanese quail. Sex differences were examined where possible. 2. GLM analysis was used to evaluate the effects of enrichment and housing, while test-retest reliability and the stability of measures over 18 d were assessed using partial correlation. 3. Foraging enrichment reduced food wastage. 4. Body weight, feed conversion, and egg production were not affected by enrichment. Rates of aggressive and feather pecking were also not significantly affected, but these behaviours were observed very infrequently in this study. 5. Socially-housed birds had poorer feather condition, lower body weight and less efficient feed conversion than singly-housed birds. Social housing did not affect food wastage. 6. There were not sex differences in feather pecking, feather condition, food wastage, or feed conversion. 7. All measures except feather pecking were reliable over 24 h, but only feather condition and body weight were stable over 18 d. The instability f the behavioural measures over time suggest that enrichment effects may vary with age.

Aggression↗
PubMed2005

Protein consumption is an important predictor of lower limb bone mass in elderly women.

BACKGROUND: The effect of protein intake on bone density is uncertain, and evidence exists for beneficial effects of both low and high protein intakes. OBJECTIVE: The objective was to study the relation between protein consumption and bone mass in elderly women with allowance for other lifestyle factors affecting bone metabolism. DESIGN: We conducted a cross-sectional and longitudinal study of a population-based sample of 1077 women aged 75 +/- 3 y. At baseline, protein consumption was measured with a food-frequency questionnaire, and bone mass and structure were measured by using quantitative ultrasound of the heel. One year later, hip bone mineral density (BMD) was measured by using dual-energy X-ray absorptiometry. RESULTS: Subjects consumed a mean (+/-SD) of 80.5 +/- 27.8 g protein/d (1.19 +/- 0.44 g protein/kg body wt). Regression analysis showed a positive correlation between protein intake and qualitative ultrasound of the heel and BMD after adjustment for age, body mass index, and other nutrients. The dose-response effect was best characterized by protein consumption expressed in tertiles, such that subjects in the lowest tertile (<66 g protein/d) had significantly lower qualitative ultrasound of the heel (1.3%) and hip BMD (2.6%) than did the subjects in the higher tertiles (>87 g protein/d). CONCLUSION: These data suggest that protein intakes for elderly women above current recommendations may be necessary to optimize bone mass.

Absorptiometry, Photon↗
PubMed2005

Behavioral treatment of obesity.

Behavioral treatment is an approach used to help individuals develop a set of skills to achieve a healthier weight. It is more than helping people to decide what to change; it is helping them identify how to change. The behavior change process is facilitated through the use of self-monitoring, goal setting, and problem solving. Studies suggest that behavioral treatment produces weight loss of 8-10% during the first 6 mo of treatment. Structured approaches such as meal replacements and food provision have been shown to increase the magnitude of weight loss. Most research on behavioral treatment has been conducted in university-based clinic programs. Although such studies are important, they tell us little about the effectiveness of these approaches in settings outside of specialized clinics. Future research might focus more on determining how these behavioral techniques can be best applied in a real-world setting.

Behavior Therapy↗