Gut fat signaling and appetite control with special emphasis on the effect of thylakoids from spinach on eating behavior.

The metabolic controls of eating are embedded in a neural system that permits an interaction with the environment. The result is an integrated adaptive response that coordinates the internal milieu with the prevailing environment. Securing adequate amounts of fat and optimizing its storage and use has an evolutionary basis. By generating neuronal and endocrine feedback signals, behavior and metabolism could then adapt to fluctuations in food availability. However, in modern society, foods that appeal to the palate are neither in shortage nor are they difficult to procure. These foods can activate brain reward circuitry beyond their evolved 'survival advantage' limits. Many foods high in fat invoke an undeniably pleasurable sensation and could excessively stimulate the brain's reward pathways leading to overeating. However, the high appeal and potential for being eaten in excess notwithstanding, fat has the added distinction of inducing powerful signals in the gut that are transduced to the brain and result in the regulation of appetite. Fatty acids are sensed by G-protein-coupled receptors on enteroendocrine cells which trigger the release of peptides involved in appetite regulation. Lipid sensing may also occur through the fatty acid translocase, CD-36, on enterocytes. Additionally, fat can activate dopaminergic systems affecting reward, to promote an inhibition over eating. Prolonging the presence of fats in the gastrointestinal lumen permits the activation of signaling mechanisms. Thylakoids, found within the chloroplasts of plants, are flattened disc-like membranous vesicles in which the light-dependent reactions of photosynthesis occur. By interacting with lipids and delaying fat digestion, thylakoid membranes promote the release of peptides involved in appetite regulation and may influence the reward system. This review explores gut lipid sensing and signaling in the context of appetite regulation. The effects of thylakoid membranes on eating behavior are also reviewed.

Candy consumption in childhood is not predictive of weight, adiposity measures or cardiovascular risk factors in young adults: the Bogalusa Heart Study.

BACKGROUND: There are limited data available on the longitudinal relationship between candy consumption by children on weight and other cardiovascular risk factors (CVRF) in young adults. The present study investigated whether candy consumption in children was predictive of weight and CVRF in young adults. METHODS: A longitudinal sample of children 10 years (n = 355; 61% females; 71% European-Americans, 29% African-Americans) who participated in cross-sectional surveys from 1973 to 1984 (baseline) and in one of two surveys (follow-ups) as young adults [19-38 years; mean (SD) = 23.6 (2.6) years] in Bogalusa, LA, were studied. Dietary data were collected using 24-h dietary recalls at baseline and at one follow-up survey; a food frequency questionnaire was used in the other follow-up survey. Candy consumers were those consuming any amount of candy. Candy consumption was calculated (g day(-1) ) from baseline 24-h dietary recalls, and was used as a covariate in the adjusted linear mixed models. Dependent variables included body mass index (BMI) and CVRF measured in young adults. RESULTS: At baseline, 92% of children reported consuming candy [46 (45) g day(-1)]; the percentage decreased to 67% [20 (30) g day(-1)] at follow-up. No longitudinal relationship was shown between baseline candy consumption and BMI or CVRF in young adults, suggesting that candy consumption was not predictive of health risks later in life. CONCLUSIONS: The consumption of nutrient rich foods consistent with dietary recommendations is important, although modest amounts of candy can be added to the diet without potential adverse long-term consequences to weight or CVRF. Additional studies are needed to confirm these results.

L-carnitine supplementation does not promote weight loss in ovariectomized rats despite endurance exercise.

In this five-week study, we tested the hypotheses that free access to a maintenance diet supplemented with L-carnitine (L-C) would reduce body fat in adult, sedentary, ovariectomized (OVX) rats, and that there would be an additive effect of L-C on weight reduction in swim-trained animals. As expected, serum carnitine was higher in rats fed the L-C diet, and the OVX-induced weight gain and abdominal fat were counteracted by swimming. L-C supplementation did not reduce the weight gain or abdominal fat in these adult female rats, Moreover, though not reaching statistical significance, rats that were fed L-C demonstrated a tendency for greater weight gain than their basal-fed counterparts despite no difference in energy intake. If the results of this study on ovariectomized rats can be translated to postmenopausal women, moderate intensity exercise may be recommended, but L-C supplementation, with no energy restriction, may be contraindicated as a weight loss method in this cohort.

Swimming eliminates the weight gain and abdominal fat associated with ovariectomy in the retired breeder rat despite high-fat diet selection.

The effects of swim-training on choice of dietary fat, carbohydrate or protein, weight gain, energy intake, and energy efficiency were examined in ovariectomized and sham-operated retired breeder rats. After a 3 week training period of increased duration, rats swam for 75 min per session (5 days per week) for 4 weeks. Ovariectomized rats gained more weight than sham rats, while swimming reduced weight gain and abdominal fat. As a percentage of total intake, macronutrient choices (weight and energy) were similar for all groups, ovariectomized animals consumed more food and more energy, compared with sham animals. All rats freely chose the majority of their food (g) as carbohydrate and the majority of energy (kJ) as fat. Results indicate that a moderate intensity training program of swimming prevented the weight gain following ovariectomy in older rats despite their excessive caloric intake of fat.

Process of conducting a 5-a-day intervention with high school students: Gimme 5 (Louisiana).

Gimme 5: A Fresh Nutrition Concept for Students (Gimme 5) was a 4-year intervention targeting increased fruit and vegetable consumption by high school students. Twelve schools were randomized to intervention or control conditions. The cohort (2,213 students; 56% female, 84% Euro-American) were followed from 9th to 12th grade. Interventions were composed of a school-based media campaign, classroom workshops, school meal modification, and parental involvement. For each of the four Gimme 5 intervention components, process evaluation measures were developed to assess program dose, penetration, and utilization, as well as external competing factors. Process evaluation results are presented to illustrate the various functions of process evaluation data. These include, but are not limited to, describing program implementation, quality control and monitoring, and explaining study outcomes. The implementation of process evaluation systems to complement the outcome measures in a high school-based intervention provides useful strategies for a more comprehensive approach to program evaluation.

Nutrient contribution of breakfast, secular trends, and the role of ready-to-eat cereals: a review of data from the Bogalusa Heart Study.

Breakfast consumption has been identified as an important factor in the nutritional well-being of children. Several studies have indicated that omission of breakfast or consumption of an inadequate breakfast is a factor contributing to poor school performance and to dietary inadequacies that are rarely compensated for in other meals of the day. Differences have also been observed in the nutrient density of the breakfast meal, depending on whether it was consumed at school or at home. Ready-to-eat cereals make a significant contribution to the nutritional quality of diets of children and young adults. The Bogalusa Heart Study, which began 25 y ago, is an epidemiologic investigation of cardiovascular risk factors and environmental determinants in a biracial pediatric population. The purpose of this review is to present data from the Bogalusa Heart Study and other studies supporting the statements above.

Cardiovascular risk factors and behavior lifestyles of young women: implications from findings of the Bogalusa Heart Study.

The primary purposes of this article are to highlight important issues related to cardiovascular risk factors and behavior life-styles in young women and to examine racial (black-white) differences in risk factors that relate to cardiovascular disease. In childhood, some girls show cardiovascular risk factors of higher blood pressure levels, dyslipidemia, and obesity, all of which continue into young adulthood. Factors that contribute to abnormal risk factors are a high-saturated fat diet, excess energy intake related to inactivity, and cigarette smoking. Trends of obesity are documented; and young white girls are continuing to use tobacco, more so than boys and black girls. Although the onset of clinical cardiovascular disease is delayed in women, the stage is set in childhood for the development of early cardiovascular risk.

Leishmania (Viannia) panamensis-specific IgE and IgA antibodies in relation to expression of human tegumentary leishmaniasis.

Leishmania (Viannia) panamensis-specific IgE and IgA antibodies were quantified in patients with parasitologically confirmed American tegumentary leishmaniasis using a radioallergosorbent test (RAST) and an enzyme-linked immunosorbent assay (ELISA), respectively. The RAST values, presented as the mean +/- SEM percentage of total isotope added, were significantly elevated in patients having disease evolution greater than 12 months (3.14 +/- 0.91), as compared with those with an evolution time of 12 or fewer months (1.66 +/- 0.15) (P = 0.017). A separate group of patients, those with eosinophils in the biopsy specimen of their lesion, also had elevated mean RAST values (2.55 +/- 0.58) when compared with patients who did not demonstrate these cells in their biopsy specimens (1.32 +/- 0.24) (P = 0.038). Leishmania-specific IgA levels, presented as the mean +/- SEM optical density, were significantly higher for patients with mucocutaneous disease (0.40 +/- 0.03) than for patients with cutaneous disease (0.28 +/- 0.023) (P = 0.0063). Inhibition testing with homologous and heterologous antigens confirmed the specificity of these assays, and were used to assess cross-reactivity among L. (Viannia) subspecies and other kineto-plastic hemoparasites. Results demonstrate that patients with more severe forms of American tegumentary leishmaniasis, defined either as increased duration of disease or invasion of the mucosa, have elevated levels of Leishmania-specific IgE and IgA antibodies, respectively.

Abnormal lung function in polyurethane foam producers. Weak relationship to toluene diisocyanate exposures.

Exposures to toluene diisocyanate (TDI) were studied for effects on respiratory health of workers in two plants manufacturing polyurethane foams. Intensive personal monitoring was used to characterize job exposures. Of 4,845 12-min personal samples, 9% exceeded 5 ppb and 1% exceeded 20 ppb. Initial questionnaire and spirometry were obtained in 386 workers (88.7% of target population). Current smoking was associated with lower mean FEV1 and FEF25-75, but percent predicted (% pred) means were normal in all smoking categories. Multiple regression showed significant adverse effects of cumulative TDI exposure on initial level of FVC and FEV1 of current smokers, and an effect at borderline significance (p less than 0.063) on FEF25-75 over all smoking categories. Logistic regression showed that chronic bronchitis was more prevalent among those with higher cumulative exposures, after controlling for smoking, age, and sex. Methacholine (MCh) reactivity was associated with reduced airway function, -8.5% pred for FEV1 and -20.0% pred for FEF25-75. In 227 with adequate follow-up, the slopes of annual change were abnormal, for example, FEV1 of -67 ml/yr in current and -53 ml/yr in never smokers. Men had worse FEV1 declines than did women, -71 ml/yr versus -43 ml/yr. TDI exposure, lifetime or concurrent, had no significant effect on slopes, despite its demonstrated effects on initial level of lung function and on prevalence of chronic bronchitis.

Evaluation of immune parameters in HIV+ subjects reporting adverse reactions to sulfamethoxazole.

Trimethoprim-sulfamethoxazole (TMP-SMX) is frequently used in human immunodeficiency virus (HIV)-infected patients (HIV+) for treatment or prophylaxis of Pneumocystis carinii pneumonia (PCP). Up to 80% of those patients report adverse reactions to that drug combination. To test the hypothesis that these reactions are immunologically mediated, we quantitated specific IgG and IgE SMX-human serum albumin (HSA) antibodies and immune complexes (IC) in HIV+ patients and in HIV controls. Patients with mild HIV disease had elevated specific SMX-HSA IgG and IC levels compared with those having severe disease or with controls. Conversely, patients with severe HIV disease had statistically elevated levels of specific IgE when compared with patients having milder disease or with controls. There were no differences in either specific antibody or IC levels between patients reporting adverse reactions and those who did not. Results suggest that there are increased levels of SMX-HSA-specific antibodies in some HIV+ patients. The presence of these antibodies appears to be related to severity of disease, rather than clinically significant drug sensitivity.

Evaluation of Basidiomycete and Deuteromycete (Fungi Imperfecti) extracts for shared allergenic determinants.

Aqueous extracts of select members of the Basidiomycetes and Deuteromycetes (Fungi Imperfecti) were evaluated for the presence of shared allergenic determinants using skin prick and radio-allergosorbent test (RAST) inhibition. Twenty adults with perennial symptoms of rhinitis, with or without asthma, were skin-prick tested with six species of Deuteromycetes and seven species of Basidomycetes. Positive weal-and-flare reactivity to Pleurotus ostreatus was associated with Alternaria alternata, Fusarium solani and Epicoccum purpurescens. Positive skin reactivity to Calvatia cyathiformis was also associated with A. alternata and F. solani. Coprinus quadrifidus was associated only with F. solani, and Psilocybe cubensis was only associated with Aspergillus fumigatus. No other skin test associations were demonstrated. For every allergen tested by RAST inhibition, significant dose-dependent homologous inhibition was demonstrated. Although the ability of an individual heterologous extract to inhibit the direct RAST varied, inhibition was generally minimal. In the most extreme example, no heterologous allergen inhibited the A. alternata RAST. However, the Armillaria tabescens RAST was inhibited 52.6%, 38.1% and 25.1% by A. fumigatus, E. purpurescens, and Penicillium notatum, respectively, suggesting significant cross-reactivity. These results suggest that, although shared allergenic determinants exist between select species of Basidiomycetes and Deuteromycetes, crossreactivity is minimal and its clinical significance is not clear. These data confirm that for reliable diagnosis of fungal allergy, representatives of both major groups must be used.

Mechanisms of occupational airways diseases induced by exposure to organic and inorganic chemicals.

Inhaled low molecular weight chemicals (LMWC) encountered in the work-place can induce airways disease. Most LMWC are irritants and if exposure levels are high enough or if there is extended exposure, can cause inflammation of the eyes, respiratory tract, and alveolar membrane without class specific antibody production or involvement of cellular mechanisms. Reflex or inflammatory bronchoconstriction may result. At lower concentrations, some of these LMWC are haptenic and induce respiratory symptoms by immune mechanisms. Dose and duration of exposure, as well as physiochemical properties of the agent and host factors, influence the effect that a given agent may have on an individual. It is important to distinguish between irritant and hypersensitivity responses for diagnostic purposes and for subsequent patient management. However, long term effects of sub-lethal exposure to primary irritants, such as SO2 or chemicals which are irritants at high concentrations but can also induce antibody formation, such as the isocyanates and acid anhydrides, are not clear.

Species-specific shrimp allergens: RAST and RAST-inhibition studies.

Two edible shrimp species are widely available in Louisiana, Penaeus setifecus (white shrimp) and Penaeus aztecus (brown shrimp). Some sensitive individuals report only occasional allergic symptoms after shrimp ingestion, suggesting that there may be species-specific allergens. To investigate this possibility, we evaluated shrimp species-specific reactivity in 31 individuals with a history of immediate hypersensitivity reactions after shrimp ingestion with skin prick tests and RASTs with white and brown shrimp extracts. On selected individuals, RAST-inhibition studies were performed with white shrimp and/or brown shrimp-coupled disks, with white and/or brown shrimp extracts as inhibiting allergen. Positive skin tests to both types of extract were observed in 77% (23/30) of the subjects; one individual reacted to brown shrimp extract only. Elevated RASTs to both extracts were observed in 16/31 study participants; one subject reacted only to white shrimp extracts and two subjects to brown shrimp extract alone. Sera from two individuals tested by RAST inhibition recognized qualitatively different allergens in brown and white shrimp extracts, supporting the hypothesis that there are species-specific shrimp allergens. Species specificity is important because it may explain the intermittent symptoms of some study subjects. The percentage of shrimp-sensitive subjects testing positive by skin test and RAST can be increased by use of extracts from more than one species of shrimp.

Basic nutritional guidelines for pediatric burn patients.

This article has described current recommendations for nutritional support of the burned pediatric patient. A checklist for monitoring the progress of pediatric burn patients from admission to discharge is included.

Antiseptal brain antibody in IgG of schizophrenic patients.

On the hypothesis that schizophrenia is an immunological disorder in which antibody is produced against a unique antigen sequestered principally or exclusively in the septal region of the brain, we used crossed-immunoelectrophoresis (CIE) to evaluate reactivity of a gamma G immunoglobulin (IgG) fraction from serum of schizophrenic patients and nonschizophrenic control subjects with homogenates of tissues of septal region, hippocampus, vermal cerebellum, frontal cortex, and liver of rhesus monkeys. When IgG fractions of unmedicated schizophrenic patients and schizophrenic patients who had received neuroleptic medication for less than 24 hr were tested against septal region homogenate, a precipitin arc was identified, indicating a positive result, with more than 95% of the fractions. In contrast, IgG fractions of schizophrenic patients who had received neuroleptic medication for more than 24 hr were rarely positive. When schizophrenic fractions that tested positive against septal region homogenate were tested against homogenates of the other tissues, they were negative. Fractions of all nonschizophrenic control subjects were negative against all homogenates.

Prevalence of basidiospore allergy in the Pacific Northwest.

Mold spore-induced respiratory allergy has been incompletely studied, and only a limited number of Fungi Imperfecti are well established as aeroallergens. Basidiomycetes, a complex and common group of fungi, which include mushrooms, rusts, smuts, brackets, and puffballs, have not been well studied. Although basidiospores can be present in high atmospheric concentrations, little is known of their aeroallergen potential. To examine this question, we performed skin prick and RASTs in 33 adult residents of Washington State using a panel of 15 common inhalant allergents that included four Fungi Imperfecti and 15 basidiospore extracts. Thirty-one of 33 (94%) subjects had positive immediate reactions to two or more common inhalants. Nine of 33 (27%) subjects responded to at least one Fungi Imperfecti; reactions were most common to Aspergillus sp. (21%), and least common to Penicillium sp., which were positive in 6%. Positive responses to basidiospore extracts were observed in 10 of 33 (30%) subjects. The prevalence of basidiospore reactivity was similar to that of Fungi Imperfecti, ranging from 18% for Scleroderma sp. to 6% for four different spore extracts. These results demonstrate that a significant number of subjects with respiratory allergies have skin test reactivity to basidiospore extracts, suggesting that these spores could be important aeroallergens in the Pacific Northwest.

Antigenic/allergenic characterization of American and German cockroach extracts.

Cockroach allergens have been implicated as clinically significant sensitizing agents in the induction/exacerbation of "urban asthma." In the present study, approximately 50% of atopic, predominantly inner-city residents had immediate wheal-and-flare cutaneous reactivity to a commercial American cockroach whole body extract. Crude whole body extracts were prepared in our laboratory from both American (Periplaneta americana) and German (Blatella germanica) cockroach species. Crossed immunoelectrophoresis of American cockroach whole body extract (AWBE) and German cockroach whole body extract (GWBE) detected a total of 50 and 56 precipitin peaks, respectively, when extracts were reacted with hyperimmunized rabbit antisera. Crossed radioimmunoelectrophoresis identified at least five electrophoretically distinct allergens each in AWBE and GWBE. Cockroach whole body extracts produced two major protein peaks when extracts were fractionated on Sephadex G-75. RAST-inhibition studies demonstrated allergens in both peak 1 and the immediate trailing fractions of the column. Direct RAST and end point prick skin testing confirmed the presence of significant/important allergens in column "fraction 2" of AWBE. Skin testing and RAST analysis suggested the occurrence of shared and species-specific allergens between AWBE and GWBE. Collectively, these studies confirm the important sensitizing potential of cockroach allergens, characterize their number and size distribution by crossed radioimmunoelectrophoresis and column chromatography, support the occurrence of significant allergens in column "fraction 2," and suggest the occurrence of both species-specific and shared interspecies allergens.