No description available.

Two experiments were conducted using newborn colostrum-deprived calves to establish the distribution of uptake of ¹²⁵I- globulin in smail intestine and to investigate effects of added microorganisms on ¹²⁵I-gamma globulin uptake. Ten calves less than 12.5 h of age (X̅ = 7 h) were anesthetized and intestines exteriorized through an abdominal incision. Intestine was ligated into 10 cm segments at 70 cm intervals beginning at the ileocecal junction, injected with ¹²⁵I-gamma globulin in an electrolyte solution and incubated for 1.5 h. One additional segment was formed adjacent to segments 1, 5 and 10 to assess effects of .5 h exposure to ¹²⁵I-gamma globulin on uptake by epithelium. After prescribed gamma globulin exposure, segments were excised, volume of lumen contents, segment weight and tissue activity were determined. Age, birth weight and intestine length were recorded. Location of each segment (PSEG) was expressed as percentage of distance from cecum to abomasum. Uptake was expressed as milligrams gamma globulin internalized per gram of segment tissue. Distribution of gamma globulin uptake after 1.5 h exposure was a cubic function of PSEG. Uptake was greatest In a region 15% of cecumabomasum distance, declining progressively towards the abomasum. After .5 4 exposure, regression of uptake on PSEG was a quadratic function with greatest uptake at 30% of cecum-abomasum distance. Uptake after 1.5 h exposure was greater than after .5 h. In experiment II, 10 calves less than 14 h of age (X̅ = 8.6 h) were anesthetized and intestines surgically exteriorized. Intestine was ligated into segments 10 cm in length at three cm intervals beginning 1.8 m above the ileocecal junction. Seven treatments were assigned in random order to segments in three successive sections of small intestine. Three treatments compared uptake in segments receiving one ml of either live intestine origin bacteria culture, sterile microbiological broth or autoclaved bacteria culture with four h incubation followed by 1.5 h exposure to ¹²⁵I-gamma globulin. Two treatments measured anaerobic microbial growth after four h incubation with one ml of either sterile broth or live bacteria culture. Residual ¹²⁵I-gamma giobulin was measured in segments receiving one ml of sterile broth or live bacteria culture with 5.5 h incubation followed by 15 second exposure to ¹²⁵I-gamma globulin. Measurements were as described for the first 10 calves. Serum corticosteroids, total protein and protein components were measured at O h and 5.5 h later. Uptake was lowest in segments receiving live bacteria as compared to segments receiving sterile inocula. Number of bacteria per gram of segment tissue was negatively correlated with uptake. Low serum corticosteroids were associated with low gamma globulin uptake. Body weight and age were not related to uptake in either experiment.in a decisive manner. / Ph. D.

Thesis (PhD)--Stellenbosch University, 2003. / ENGLISH ABSTRACT: This study investigated the effect of several hormones on the rat corticosteroid binding globulin proximal promotor and for the first time showed that modulation occurs at the promotor level and can be correlated with changes in corticosteroid binding globulin mRNA and protein levels. The effect of various physical and psychological stressors on rat liver corticosteroid binding globulin mRNA levels was also tested and it was shown that voluntary running had no effect on rat corticosteroid binding globulin levels but that involuntary swimming and immobilization decreased rat corticosteroid binding globulin mRNA levels. Glucocorticoid responsiveness of the corticosteroid binding globulin promoter was investigated further by using truncated contructs of the corticosteroid binding globulin proximal promoter. Glucocorticoid responsiveness was delineated to between -296 and -145bp from the transcription start site an area that contains putative binding sites for D-site binding protein, hepatic nuclear factor-3 and CAAT/enhancer binding protein suggesting that these transcription factors may be involved in glucocorticoid responsiveness of the corticosteroid binding globulin proximal promoter. The dissociative glucocorticoid activity of medroxyprogesterone acetate and Compound A, both putative dissociated glucocorticoids, was compared to standard glucocorticoids by examining transactivation of glucocorticoid response element-containing reporter constructs and transrepression of corticosteroid binding globulin gene expression in hepatic cell lines. Results showed that medroxyprogesterone acetate, but not Compound A, trans activates only in the presence, but not in the absence, of co-transfected glucocorticoid receptor. Medroxyprogesterone acetate down modulated dexamethasone transactivation while the modulatory effect of Compound A depends on the order of addition of Compound A. If added together Compound A has no effect on dexamethasone transactivation, however, if Compound A was added before dexamethasone, Compound A significantly decreased dexamethasone transactivation. Both medroxyprogesterone acetate and Compound A, like glucocorticoids, transrepressed the rat corticosteroid binding globulin proximal promoter. The potency of repression was similar but Compound A repressed with a higher efficacy than medroxyprogesterone acetate. We conclude that Compound A is a completely dissociated glucocorticoid in contrast to medroxyprogesterone acetate that displays only partial dissociation, which is dependent on glucocorticoid receptor levels. / AFRIKAANSE OPSOMMING: Tydens hierdie ondersoek is die effek van verskeie hormone op die rot kortikosteroied bindings globulien proksimale promoter ondersoek en vir die eerste keer is getoon dat modulering plaasvind op promoter-vlak en dat repressie korrileer met die verandering in kortikosteroied bindings globulien mRNA-en proteinvlakke. Die effek van verskeie fisiese en fisiologiese stressors op rotlewer kortikosteroied bindings globulien-mRNAvlakke is ook getoets en daar is getoon dat willekeurige hardloop geen effek op rot kortikosteroied bindings globulien-mRNA-vlakke het nie maar dat gedwonge swem en immobilisering rot kortikosteroied bindings globulien-mRNA-vlakke verlaag. Glukokortikoied responsiewiteit van die kortikosteroied bindings globulien proksimale promoter is verder ondersoek deur verkorte konstrukte van die kortikosteroied bindings globulien te toets. Glukokotikoied responsiewiteit is afgebaken tot tussen -296 en - 145bp vanaf die transkripsie beginplek 'n area wat beweerde bindings setels vir D-setel bindings protein, hepatosiet faktoor-3 en CCAAT-bindings protein-2 bevat en dus suggereer dat hierdie transkripsie faktore betrokke mag wees met glukokortikoied effekte op die kortikosteroied bindings globulien-proksimale promoter. Die dissosiatiewe glukokortikoied aktiwiteit van medroksiprogesteroon asetaat en Verbinding A, beide beweerde dissosiatiewe glukokortikoiede, relatief tot standaard glukokortikoiede is vergelyk deur transaktivering van glukokortikoied reseptor e1elment-bevattende konstrukte en onderdrukking van kortikosteroied bindings globulien geen ekspressie in lewersellyne te bestudeer. Medroksiprogesteroon asetaat, maar nie Verbinding A nie, transaktiveer slegs in die teenwoordigheid, maar nie in die afwesigheid, van ko-getransfekteerde glukokortikoied reseptore. Medroksiprogesteroon asetaat moduleer deksametasoon transaktivering afwaarts terwyl die modulerende effek van Verbinding A afhanklik van die orde van Verbinding A byvoeging is. Indien saam bygevoeg het Verbinding A geen effek op deksametasoon transaktivering nie, maar indien Verbinding A voor deksametasoon bygevoeg word verlaag Verbinding A deksametasoon transaktivering. Beide medroksiprogesteroon asetaat and Verbinding A, soos glukokortikoiede, onderdruk die rot kortikosteroied bindings globulien-proksimale promoter. Die sterkte van onderdrukking is dieselfde maar Verbinding A onderdruk met 'n hoër effektiwiteit as medroksiprogesteroon asetaat. Ons toon dat Verbinding A 'n totale dissosiatiewe glukokortikoied is in teenstelling met medroksiprogesteroon asetaat, wat slegs gedeeltelik dissosiatief is afhangende van glukokortikoied reseptor-vlakke.

Thesis (Ph. D.)--Institute of Paper Chemistry, 1969. / Includes bibliographical references (p. 63-65).

Thesis (M.S.)--Brigham Young University. Dept. of Plant and Wildlife Sciences, 2008. / Includes bibliographical references (p.62-71).

<p>Predmet doktorske disertacije je izučavanje različitih bioprocesa za modifikovanje biljnih globulina radi unapređenja njihovih funkcionalnih karakteristika. Istraživanja su zasnovana na karakterizaciji i enzimskoj modifikaciji glavnog rezervnog proteina (12S), kukurbitina, iz semena uljane tikve (<em>Cucurbita pepo</em>). Osnova istraživanja je enzimska konverzija globulina i dobijanje proteinskih modifikata delovanjem hidrolaza i transferaza. U okviru istraživanja, enzimski procesi modifikacije globulina izučavani su sa dva aspekta: enzimska hidroliza i enzimsko umrežavanje (cross-linking), primenom komercijalnih enzimskih preparata. Takođe istraživanja obuhvataju i razvoj i kontrolu samih bioprocesa definisanjem i optimizacijom procesnih parametara (temperature, pH, koncentracije enzima i supstrata, vreme reakcije). Ovako definisani procesi eksploatisani su u cilju kreiranja željenih funkcionalnih karakteristika proteina spram njihove potencijalne primene u formulacijama hrane. Odabir i optimizacija procesnih parametara i modelovanje bioprocesa izvedeno je implementiranjem nove kompjuterske i analitičke metodologije</p> / <p>The PhD thesis research is aimed at development of different bioprocesses for modification of plant globulins in order to improve their functional properties. Studies are based on characterization and enzymatic modification of major storage protein (12S), cucurbitin derived from pumpkin oil seed (<em>Cucurbita pepo</em>). The base of research is enzymatic conversion of cucurbitin by hydrolase and transferase. Two different enzymatic processes are used for protein modification: (i) enzymatic hydrolysis and (ii) enzymatic cross-linking. To monitor, control the bioprocesses, and definition of process parameters, such as temperature, pH, enzyme-substrate ratio, reaction time, Response Surface Methodology (RSM) was used. In addition, RSM was employed for production of protein modification with desired functional properties.</p>

Graduation date: 1996

No description available.

Diss. (sammanfattning) Stockholm : Univ. / Återtagen utgåva. Härtill 5 uppsatser.

Diss. (sammanfattning) Stockholm : Karol. inst., 1999. / Härtill 5 uppsatser.