800 research outputs found

    Effects of organically and conventionally produced feed on biomarkers of health in a chicken model

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    Consumers expect organic products to be healthier. However, limited research has been performed to study the effect of organic food on health. The present study aimed to identify biomarkers of health to enable future studies in human subjects. A feeding experiment was performed in two generations of three groups of chickens differing in immune responsiveness, which were fed identically composed feeds from either organic or conventional produce. The animals of the second generation were exposed to an immune challenge and sacrificed at 13 weeks of age. Feed and ingredients were analysed on macro- and micronutrients, i.e. vitamins, minerals, trace elements, heavy metals and microbes. The chickens were studied by general health and immune parameters, metabolomics, genomics and post-mortem evaluation. The organic and conventional feeds were comparable with respect to metabolisable energy. On average, the conventionally produced feeds had a 10 % higher protein content and some differences in micronutrients were observed. Although animals on both feeds were healthy, differences between the groups were found. The random control group of chickens fed conventional feed showed overall a higher weight gain during life span than the group on organic feed, although feed intake was mostly comparable. The animals on organic feed showed an enhanced immune reactivity, a stronger reaction to the immune challenge as well as a slightly stronger ‘catch-up growth’ after the challenge. Biomarkers for future research were identified in the parameters feed intake, body weight and growth rate, and in immunological, physiological and metabolic parameters, several of these differing most pronounced after the challeng

    Characterization of iodothyronine sulfotransferase activity in rat liver

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    Sulfation is an important pathway in the metabolism of thyroid hormone because it strongly facilitates the degradation of the hormone by the type I iodothyronine deiodinase. However, little is known about the properties and possible regulation of the sulfotransferase(s) involved in the sulfation of thyroid hormone. We have developed a convenient method for the analysis of iodothyronine sulfotransferase activity in tissue cytosolic fractions, using radioiodinated 3,3'-diiodothyronine (3,3'-T2) as the preferred substrate, unlabeled 3'-phosphoadenosine-5'-phosphosulfate (PAPS) as the sulfate donor, and Sephadex LH-20 minicolomns for separation of the products. We found that iodothyronine sulfotransferase activity in rat liver cytosol is 1) higher in male than in female rats; 2) optimal at pH 8.0; 3) characterized (at 50 microM PAPS and pH 7.2) by apparent Michaelis-Menton (Km) values for 3,3'-T2 of 1.77 and 4.19 microM, and Vmax values of 1.94 and 1.45 nmol/min per mg protein in male and female rats, respectively; 4) characterized (at 1 microM 3,3'-T2 and pH 7.2) by apparent Km values for PAPS of 4.92 and 3.80 microM and Vmax values of 0.72 and 0.31 nmol/min per mg protein, in males and females, respectively; 5) little affected by hyperthyroidism in both male and female rats, but significantly decreased by hypothyroidism in males but not in females; and 6) not affected by short-term (3 days) fasting in both male and female rats, but significantly decreased by long-term (3 weeks) food restriction to one-third of normal intake in males but not in females. It is suggested that the higher hepatic iodothyronine sulfotransferase activity in male vs. female rats, as well as the decreases induced in males by hypothyroidism and long-term food restriction, represents differences in the expression of the male-dominant isoenzyme rSULT1C1

    Neural differentiation of the human neuroblastoma cell line IMR32 induces production of a thyrotropin-releasing hormone-like peptide

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    The human neuroblastoma cell line IMR32 produces and secretes substantial amounts of TRH-immunoreactivity (TRH-IR) as measured with radioimmunoassay (RIA) using the nonspecific antiserum 4319. It was found that synthesis of TRH-IR is dependent on neural differentiation: under serum-free conditions these cells exhibit neural characteristics as defined by morphological and biochemical standards. After culture for 2–5 days in serum-free medium cells grew large neural processes and expressed neuron-specific markers whereas glial-specific markers were absent. TRH-IR became detectable after 4–8 days serum-free conditions. Northern blot and chromatographic analysis, however, failed to detect proTRH mRNA and authentic TRH in these cells. Moreover, TRH-IR was undetectable in the RIA using TRH-specific antiserum 8880. TRH-IR produced by differentiated cells was retained on a QAE Sephadex A-25 anion-exchange column and thus negatively charged. HPLC analysis showed coelution with the synthetic peptide pGlu-Glu-ProNH2. Study of the mechanisms regulating production of this novel peptide in these cells should further elucidate the role differentation plays in the synthesis of neuropeptides

    Breeding for improved welfare in pigs: a conceptual framework and its use in practice

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    Welfare of animals can be defined as the kind of feelings the environmental conditions bring about in the animals. These feelings depend on the needs of the animals and their degree of satisfaction. Needs of animals, and so their welfare, are partly genetically determined. Therefore, welfare can be changed by breeding. The aim of this study was to investigate how welfare of pigs under modern intensive farm conditions can be improved by genetic selection, with emphasis on the precise definition of the breeding goal and determination of the animal characteristics on which selection can be based in practice. The existing thermoregulation model was used to develop a conceptual framework that describes welfare of growing pigs and production sows with respect to each of their needs as a curvilinear function of the respective environmental conditions. The framework assumes that welfare in terms of feelings is reflected by the physiological and behavioural mechanisms the pig has to activate in order to cope with the various environmental conditions it encounters. Based on those physiological and behavioural responses to changing conditions, five welfare zones can be distinguished for each need. Breeding goals for welfare were defined in terms of the transition points between these welfare zones, such that future pigs would better cope with unfavourable or unfamiliar farming conditions, therewith quickening the domestication process, to some extent. However, as long as genetic parameters for these transition points are not available, more common welfare-related characteristics like temperament, stress resistance and robustness can be included in the breeding goal, as an alternative. For selection among potential breeding candidates, transition points between welfare zones can be determined in sib tests, thereby also collecting the data for estimating genetic parameters. As a cheaper alternative, breeding candidates could be tested under hard conditions and selected on their coping success. In addition, various behavioural tests and operant conditioning tests ( to test a pig's motivation to change its actual environment) can be carried out. Under common conditions on the farm, problems associated with coping (like incidences of diseases, injuries, and stereotypies) and/or other relevant traits ( e. g. saliva cortisol levels, longevity and even production traits) should be recorded routinely and used as selection index information. Selection for improved welfare should lead to more tolerant pigs that are better able to cope with possible unfavourable farm conditions by a more efficient use of the adaptation mechanisms they already possess. It should, however, not result in lowering husbandry standards. More research is needed to assess genetic correlations among various welfare aspects and with production traits to prevent undesired side effects in future populations of pigs

    Evidence that the TRH-like peptide pyroglutamyl-glutamyl-prolineamide in human serum may not be secreted by the pituitary gland

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    Recent studies have revealed that TRH-like immunoreactivity (TRH-LI) in human serum is predominantly pGlu-Glu-ProNH2 (< EEP-NH2), a peptide previously found in, among others tissues, the pituitary gland of various mammalian species. In the rat pituitary, < EEP-NH2 is present in gonadotrophs and its pituitary content is regulated by gonadal steroids and gonadotrophin-releasing hormone (GnRH). Hence, we reasoned that < EEP-NH2 in human serum may also arise, at least in part, from the pituitary, and that its secretion may correlate with that of gonadotrophins. Therefore, blood was simultaneously sampled from both inferior petrosal sinuses, which are major sites of the venous drainage of the pituitary gland, and a peripheral vein from seven patients with suspected adrenocorticotrophin-secreting pituitary tumours. In addition, in six postmenopausal and six cyclic women, peripheral vein blood was collected at 10-min intervals for 6 h, then a standard 100 micrograms GnRH test was performed. In the sera, TRH-LI was estimated by RIA with antiserum 4319, which binds most tripeptides that share the N- and C-terminal amino acids with TRH (pGlu-His-ProNH2). In addition, LH and FSH were measured in these sera b

    Mediators of physical activity change in a behavioral modification program for type 2 diabetes patients

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    Background: Many studies have reported significant behavioral impact of physical activity interventions. However, few have examined changes in potential mediators of change preceding behavioral changes, resulting in a lack of information concerning how the intervention worked. Our purpose was to examine mediation effects of changes in psychosocial variables on changes in physical activity in type 2 diabetes patients.Methods: Ninety-two patients (62 ± 9 years, 30, 0 ± 2.5 kg/m, 69% males) participated in a randomized controlled trial. The 24-week intervention was based on social-cognitive constructs and consisted of a face-to-face session, telephone follow-ups, and the use of a pedometer. Social-cognitive variables and physical activity (device-based and self-reported) were collected at baseline, after the 24-week intervention and at one year post-baseline. PA was measured by pedometer, accelerometer and questionnaire.Results: Post-intervention physical activity changes were mediated by coping with relapse, changes in social norm, and social modeling from family members (p ≤ 0.05). One-year physical activity changes were mediated by coping with relapse, changes in social support from family and self-efficacy towards physical activity barriers (p ≤ 0.05). Conclusions: For patients with type 2 diabetes, initiatives to increase their physical activity could usefully focus on strategies for resuming regular patterns of activity, on engaging family social support and on building confidence about dealing with actual and perceived barriers to activity.Trial Registration: NCT00903500, ClinicalTrials.gov
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