Dissertations / Theses: 'Physiological transport'

1

Aiken, Simon Piers. "Physiological transport of zinc." Thesis, University of Southampton, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278677.

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2

Thomas, Collin Ernest. "Extracellular ATP : transport, metabolism, and physiological significance /." Digital version accessible at:, 1999. http://wwwlib.umi.com/cr/utexas/main.

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3

Carrithers, John A. "Effects of post-exercise carbohydrate-protein feedings on muscle glycogen restoration." Virtual Press, 1999. http://liblink.bsu.edu/uhtbin/catkey/1133741.

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The purpose of this investigation was to determine the effects of post-exercise carbohydrate-protein feedings on muscle glycogen restoration following exhaustive cycle ergometer exercise. Seven male collegiate cyclist (age=25.6±3.3y, ht.=180.9±8.5cm, wt.=75.4±10.7kg, VO2max=4.20±0.4 1•miri 1) performed three trials, each separated by -lwk, 1) 100% (x-D glucose (CHO), 2) 70% carbohydrate-20% protein-10% fat (CHOPRO), and 3) 86% carbohdyrate-14% amino acid (CHO-AA). All feedings were eucaloric, based upon 1.0 g•kgb.W.'1•hr"1 of carbohydrate, and administered every half hour during a four hour muscle glycogen restoration period in an 18% wt./vol. solution. Muscle biopsies were obtained immediately and four hours post exercise. Following the exhaustive exercise and every half hour for four hours a blood sample was drawn. Muscle glycogen concentrations increased 53%, 47%, and 57% for the CHO, CHO-PRO, and CHO-AA feedings, respectively, however no differences among the feedings were apparent in muscle glycogen restoration. The plasma glucose and insulin concentrations demonstrated no differences throughout the restoration period among the three feedings. These results suggest that muscle glycogen restoration does not appear to be enhanced with the addition of either protein or amino acids to an eucaloric carbohydrate feeding following an exhaustive cycle exercise. However, it appears that if adequate amounts of carbohydrates are consumed (greater than 0.70 g•kgb,W,."'•hf' carbohydrate) following exhaustive exercise, maximal muscle glycogen restoration occurs.
School of Physical Education

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4

Schaedler, Theresia Anna. "Molecular mechanism of transport by the secondary-active multidrug transporter LmrP." Thesis, University of Cambridge, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609036.

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5

Wu, Linyan, and wu0071@flinders edu au. "BRAIN DERIVED NEUROTROPHIC FACTOR TRANSPORT AND PHYSIOLOGICAL SIGNIFICANCE." Flinders University. Medicine, 2007. http://catalogue.flinders.edu.au./local/adt/public/adt-SFU20071204.113001.

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Neurotrophins are important signaling molecules in neuronal survival and differentiation. The precursor forms of neurotrophins (proneurotrophins) are the dominant form of gene products in animals, which are cleaved to generate prodomain and mature neurotrophins, and are sorted to constitutive or regulated secretory pathway and released. Brain-derived neurotrophic factor (BDNF) plays a pivotal role in the brain development and in the pathogenesis of neurological diseases. In Huntingtons disease, the defective transport of BDNF in cortical and striatal neurons and the highly expressed polyQ mutant huntingtin (Htt) result in the degeneration of striatal neurons. The underlying mechanism of BDNF transport and release is remains to be investigated. Current studies were conducted to identify the mechanisms of how BDNF is transported in axons post Golgi trafficking. By using affinity purification and 2D-DIGE assay, we show Huntingtin-associated protein 1 (HAP1) interacts with the prodomain and mature BDNF. The GST pull-down assays have addressed that HAP1 directly binds to the prodomain but not to mature BDNF and this binding is decreased by PolyQ Htt. HAP1 immunoprecipitation shows that less proBDNF is associated with HAP1 in the brain homogenate of Huntingtons disease compared to the control. Co-transfections of HAP1 and BDNF plasmids in PC12 cells show HAP1 is colocalized with proBDNF and the prodomain, but not mature BDNF. ProBDNF was accumulated in the proximal and distal segments of crushed sciatic nerve in wild type mice but not in HAP1-/- mice. The activity-dependent release of the prodomain of BDNF is abolished in HAP1-/- mice. We conclude that HAP1 is the cargo-carrying molecule for proBDNF-containing vesicles and plays an essential role in the transport and release of BDNF in neuronal cells. 20-30% of people have a valine to methionine mutation at codon 66 (Val66Met) in the prodomain BDNF, which results in the retardation of transport and release of BDNF, but the mechanism is not known. Here, GST-pull down assays demonstrate that HAP1 binds Val66Met prodomain with less efficiency than the wild type and PolyQ Htt further reduced the binding, but the PC12 cells colocalization rate is almost the same between wt prodomain/HAP1 and Val66Met prodomain/HAP1, suggesting that the mutation in the prodomain may reduce the release by impairing the cargo-carrying efficiency of HAP1, but the mutation does not disrupt the sorting process. Recent studies have shown that proneurotrophins bind p75NTR and sortilin with high affinity, and trigger apoptosis of neurons in vitro. Here, we show that proBDNF plays a role in the death of axotomized sensory neurons. ProBDNF, p75NTR and sortilin are highly expressed in DRG neurons. The recombinant proBDNF induces the dose-dependent death of PC12 cells and the death activity is completely abolished in the presence of antibodies against the prodomain of BDNF. The exogenous proBDNF enhances the death of axotomized sensory neurons and the antibodies to the prodomain or exogenous sortilin-extracellular domain-Fc fusion molecule reduces the death of axotomized sensory neurons. We conclude that proBDNF induces the death of sensory neurons in neonatal rats and the suppression of endogenous proBDNF rescued the death of axotomized sensory neurons.

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6

Ryder, Jeffrey W. "The effects of fasting and refeeding on insulin-like growth factor-I stimulated glucose transport." Virtual Press, 1996. http://liblink.bsu.edu/uhtbin/catkey/1020146.

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Insulin-like growth factor-I (IGF-I) is a known stimulator of glucose transport. IGF binding protein 1 (IGFBP1) is a protein that regulates the actions of IGF-I by binding to IGF-I which alters it's ability to bind to the IGF-I receptor. Diet and exercise may influence this system. While IGFBP1 levels increase with fasting or prolonged exercise, feeding will reverse this elevation. The intent of this study was to determine if an in vivo manipulation of IGFBP1 affects in vitro glucose transport in the rat soleus. Sixteen male Spaque Dawley rats were fasted for 12 hours. Half of the animals were then allowed a two hour ad libitum refeeding period. Animals were anesthetized and had their soleus muscles removed. Muscles were then randomly assigned to one of four treatment groups. Treatments involved an incubation in either 4 or 8 mM glucose in either the presence or absence of IGF-I (75 ng x ml"'). Final incubation for all treatment groups included [3H]-3-O-methylglucose (437 µCi x mM-) for the measurement of glucose transport. Following incubation, muscles were weighed, homogenized in 1 ml of 10% trichloroacetic acid, and centrifuged to precipitate out protein. 100 µl of the supernatant was added to 3 ml of scintillation fluid and analyzed in a scintillation counter. Glucose transport was determined by 3H activity. A statistical analysis of the various groups shows that there is no significant difference between fasted and refed animal for any specific treatment. However, when all the fasted and refed animals area grouped, glucose transport rate is significantly greater (p<0.05) in fasted (3.59 ± 0.44 µM x ml"' x hr) animals than in refed animals (2.56 ± 0.27 µM x ml"' x hr'). Additionally, muscles that were treated with IGF-I in 8 mM glucose demonstrated a greater rate of glucose transport (5.12 ± 0.68 µM x ml-1 x hr') than all other treatments (2.13 ± 0.39 to 2.90 ± .33 µM x ml-' x hr'). This study showed that IGF-I is a stimulator of glucose transport in an 8 mM glucose media. Additionally, the results show that glucose transport is greater if the animals are fasted. The differences between fasted and refed animals demonstrated in this study supports the hypothesis that diet manipulated IGFBP1 levels are able to alter the biological effects of IGF-I.
School of Physical Education

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7

Mernone, Anacleto Valentino. "A mathematical study of peristaltic transport of physiological fluids." Title page, contents and summary only, 2000. http://web4.library.adelaide.edu.au/theses/09PH/09phm566.pdf.

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8

Fortner, Stephanie A. "The effect of PAF, Lyso-PC, and Acyl-PAF on zinc diffusion and the comparison of transport mechanisms of cadmium, lead, copper, and manganese to zinc through a lipid bilayer." Virtual Press, 2000. http://liblink.bsu.edu/uhtbin/catkey/1164847.

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A method was developed which allowed for more consistent liposome quality, reducing the standard error of initial rates for Zn2+ diffusion by 30%. Introducing low concentration of platelet-activating-factor (PAF), 1-palmitoyl-L-lyso-3-phosphocholine (Lyso-PC), or 1-oleoyl-2-acetyl-sn-glycero-3-phosphocholine (Acyl-PAF) to 1palmitoyl.-2-oleoyl-sn-glycero-3-phosphocholine (POPC) liposomes did not have any noticeable impact on zinc diffusion. Since diffusion is dependent on membrane composition and properties, it can be concluded that PAF, Lyso-PC, and Acyl-PAF did not alter POPC liposome properties significantly. Zn2+ and Cd2+ kinetic experiments showed binding to the liposome surface prior to diffusion and a mutual diffusing species, the monohydroxo complex. Although Mn 2+ did not diffuse to any measurable extent, binding to the liposome surface was also observed. Cue+ and Pb 2+ on the other hand follow a more complex diffusion mechanism, which requires further investigation.
Department of Chemistry

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9

Xu, Fan 1960. "Effect of prolonged exercise on running economy." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=68149.

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The purpose of this study was to investigate the effect of prolonged exercise on running economy. Fourteen male long distance runners performed two 90 minute runs on an outdoor 400m track at velocities equal to 65 and 80% of VO$ sb2$max. Prior to and following each 90 minute run, running economy (RE) was measured as the steady-state VO$ sb2$ during treadmill runs at speeds of 188 and 228 m/min. During the 90-min run at 65% of VO$ sb2$max, the mean weight loss was 1.3 kg. The HR was 143 bpm between minutes 5-10 and increased to 150 bpm between minutes 85-90. During the 90-min run at 80% of VO$ sb2$max, the mean weight loss was 1.4 kg. The HR was 161 bpm between minutes 5-10 and increased to 165 bpm between minutes 85-90. When the post RE test was conducted following each 90-min run, there was a significant increase in VO$ sb2$ expressed in both l/min and ml/kg$ cdot$min (a decrease in running economy). The increase in oxygen cost of running following the 90-min run at 80% of VO$ sb2$max was greater than that following the run at 65% of VO$ sb2$max.

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10

Deschuyteneer, Aude. "Rhesus factors: structure-function analysis and physiological role in mouse." Doctoral thesis, Universite Libre de Bruxelles, 2014. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209354.

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Proteins of the conserved Mep-Amt-Rh superfamily, including mammalian Rhesus factors,

mediate ammonium transport. Ammonium is an important nitrogen source for the

biosynthesis of amino acids for instance but its accumulation is also known as cytotoxic in

animals. Nevertheless, the controlled disposal of ammonium in urine plays a critical role in

the regulation of the acid-base homeostasis. Alteration in ammonium transport via human Rh

proteins could have clinical outcomes. In this work, we addressed aspects of structurefunction

analysis of altered human Rhesus proteins using a heterologous expression system

and further characterized aspects of the patho-physiological roles of Rh proteins using

knockout mice models available in the laboratory.

Using a yeast-based expression assay, we characterized human Rh variants resulting from non

synonymous single nucleotide polymorphisms (nsSNPs) with known or unknown clinical

phenotypes. The HsRhAG variants (I61R, F65S) associated to overhydrated hereditary

stomatocytosis (OHSt), a disease affecting erythrocytes, proved affected in intrinsic

bidirectional ammonium transport, suggesting altered ammonium transport as a potential

hallmark of the disease. Moreover, these variants showed trans-dominant negative effects on

the activity of their native HsRhAG counterpart, suggesting altered cooperation of the

subunits in “heteromeric” transport complexes. On the other hand, we revealed that the

R202C variant of HsRhCG, the orthologue of mouse Rhcg required for optimal urinary

ammonium excretion and blood pH control, shows an impaired inherent ammonium transport

activity. HsRhCGR202C may potentially confer susceptibility to disorders leading to metabolic

acidosis for instance.

MmRhcg has been shown to be expressed in the male mice epididymal tract, its absence

leading to a more acidic luminal fluid and to a reduced male fertility. Using mice

models, we further investigated the role of Rhcg and Rhbg proteins in the male

reproductive function.

Doctorat en Sciences
info:eu-repo/semantics/nonPublished

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11

Kiteala, Lori. "The relationship between exercise intensity, pulmonary diffusion and hemoglobin saturation in competitive endurance athletes." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=26074.

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The goal of the present investigation was to evaluate the role of the pulmonary diffusion capacity (as measured by DLco) in relation to exercise-induced hypoxemia in elite athletes working at near maximal exercise intensities. Twenty-four elite cyclists were submitted to a direct measurement of VO$ sb2$ max on cycle ergometer which permitted classification into one of two groups. "Desaturaters" (N = 13) if oxyhemoglobin saturation (SaO$ sb2$%), as determined by finger oxymetry, fell below 91% or "non-desaturaters" if SaO$ sb2$% remained above 91%. Subsequent determinations of the transfer capacity for CO (DLco) were made using a 3 second breath-hold technique (Gould 2400/2450), at rest as well as at 60% and 90% of previously determined VO$ sb2$ max ($>$4.0 1/min). The results show an increase in DLco from rest to the first exercise intensity (desat: 41.7 $ pm$ 5.7 to 55.1 $ pm$ 4.7; non-desat: 41.1 $ pm$ 5.8 to 57.2 $ pm$ 6.9 mlsCO/mmHg/min) without much further increase to the maximal workload (desat: 61.0 $ pm$ 6.0; non-desat: 61.4 $ pm$ 9.5 mls CO/mmHg/min). No significant differences in DLco were found between the two groups at rest or either of the two exercise intensities. Significant differences between the desat and non-desat groups were found for FVC, post-exercise FEF$ sb{25-75 %}$, and VE/VO$ sb2$.
The present results are in agreement with previous reports showing arterial desaturation in 50% of highly-trained subjects when VO$ sb2$ max $>$4.0 1/min. The present investigation cannot clearly establish the role of DLco in this response. (Abstract shortened by UMI.)

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12

Ahlers, Belinda A. "Regulated L-Arginine transport in heart failure." Monash University, Faculty of Medicine, 2003. http://arrow.monash.edu.au/hdl/1959.1/9521.

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13

Diderich, Jasper Andries. "Physiological functions of hexose transport and hexose phosphorylation in Saccharomyces cerevisiae." [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2001. http://dare.uva.nl/document/60420.

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14

Darley, Catherine P. "The physiological roles of the vacuolar proton-pumping pyrophosphatase." Thesis, University of York, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337633.

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15

McGruer, David. "Inclined treadmill running economy and uphill running performance." Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61922.

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16

Du, Xiubo, and 都秀波. "Characterization of the N-terminus of human copper transporter (HCTR1)and mechanism comparison between the cellular uptake of Cu andcisplatin via HCTR1." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B46080065.

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17

Semra, Yemane Kurban. "Endogenous ouabain-like immunoreactive substance (OLIS) : characterisation and physiological studies." Thesis, King's College London (University of London), 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313282.

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18

Engevik, Melinda A. "Ion Transport and the Gut Microbiota." University of Cincinnati / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1397466973.

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19

Wang, Xinghao, and 王星昊. "Platinum on the road: the activation and transport of novel platinum anticancer drugs by the extracellulardomain of human copper transporter I (HCTR1)." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2012. http://hub.hku.hk/bib/B48199205.

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Platinum-based anticancer drugs such as cisplatin, carboplatin and nedaplatin have been widely used in the chemotherapy of a variety of solid tumours for several decades. However, the development of both inherent and acquired resistance has greatly limited the efficacy of all of these drugs. Several mechanisms were proposed to explain the cellular resistance to these platinum drugs, including decreased drug accumulation. Previously, it was suggested that cisplatin enters cells via passive diffusion, followed by intracellular hydrolysis and activation prior to targeting DNA. However, recent in vivo and in vitro studies confirmed that transporters and carriers involved in copper homeostasis play important roles on the transport as well as cellular resistance to the platinum drugs. CTR1, a major plasma-membrane transporter involved in intracellular copper(I) homeostasis, was found to facilitate the uptake of several platinum drugs although the molecular mechanism remains unclear. The extracellular N-terminal domain of human CTR1 (hCTR1) with two methionine(Met)-rich and two histidine(His)-rich motifs has been proved to be essential for the uptake of both copper and platinum drugs by the transporter. In this thesis, the extracellular domain of hCTR1 (hCTR1_N, residues 1-55) was overexpressed and the role of the Met- and His-rich motifs on cisplatin binding was examined by either mutagenesis or chemical modification. Cisplatin was found to directly and rapidly bind to the Met residues of hCTR1_N by the formation of monofunctional cisplatin-thioether adducts. The kinetics of the binding process was found to correlate with the number of Met residues, indicating that all Met residues are exposed to solvents and capable for cisplatin binding. Such a non-sequence-specific binding may increase the likelihood of capturing the anticancer drug in extracellular fluid by the N-terminus of hCTR1. The effect of hCTR_N on the binding and activation of second-generation platinum anticancer drugs, e.g. carboplatin and nedaplatin, were subsequently investigated. hCTR1_N was found to significantly facilitate the activation of these platinum drugs by the formation of ring-opened monofunctional Pt-thioether species through Met residues. Although the activities of platinum drugs against hCTR1_N are significantly different, their monofunctional protein-bound species demonstrated great similarity in both structure and kinetic aspects, suggesting the uptake of these platinum drugs by hCTR1 might follow the same mechanism. The formation of active ring-opened species of carboplatin and nedaplatin by chloride/bicarbonate was observed, indicating these nucleophiles may play a critical role in the pre-activation of the drugs prior to their reaching cellular targets. Pt-thioether species were proposed as intermediates for the platination of other biomolecules. The monofunctional cisplatin adduct of hCTR1_N was proved to further transfer its active platinum species to either cysteine- or guaninecontaining biomolecules which mimic the C-ternimus of hCTR1 and DNA. Methionine residues of hCTR1 may therefore serve as key residues for the activation and transport of platinum anticancer drugs in the form of monofunctional Pt-thioether species through the pole of trimeric hCTR1 and eventually to their final target – DNA.
published_or_final_version
Chemistry
Doctoral
Doctor of Philosophy

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20

Katano, Masahiro. "Elucidation of physiological significance of proteins related to transport of divalent cations." 京都大学 (Kyoto University), 2011. http://hdl.handle.net/2433/151997.

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21

Muzyamba, Morris Chivwaba. "Physiological and pathological modulation of Kâº transport in red blood cells." Thesis, University of Liverpool, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343617.

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22

Aida, Adlimoghaddam. "Molecular and physiological characterization of the nitrogen transport system in Caenorhabditis elegans." Journal of experimental biology (JEB), 2014. http://hdl.handle.net/1993/30721.

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In this study, we investigated the mechanism of nitrogen excretion in the soil nematode Caenorhabditis elegans. Utilizing the scanning ion electrode technique (SIET), it was shown for the first time in nematodes that the excretory cell promotes a secretion of ions, including Na+, K+, H+ and Ca2+. In addition, observations from experiments exposing the animal to various environmental pH regimes suggested that the mode of ammonia excretion is dependent on acidification of the unstirred boundary layer, supported also by a detected H+-net-excretion over the hypodermis employing SIET. Pharmacological experiments, SIET and enzyme activity measurements implicated the participation of a functional microtubule network, V-type H+-ATPase, carbonic anhydrase, Na+/K+-ATPase, and apical Na+-channels in the ammonia excretion mechanism of this roundworm. Most importantly, employing ammonia transporter deficient Saccharomyces cerevisiae we were able to show for the first time that an invertebrate Rh-like protein (Rhr-1) does indeed function as an ammonia transporter. Further, a second Rh-protein, Rhr-2, was found to be predominantly expressed in the hypodermis. Knock-out experiments on this transporter further suggested participation of Rhr-2 in the apical ammonia trapping mechanism. Overall, the results of this study provided evidence for a novel ammonia excretion mechanism over the hypodermis, which exhibits features commonly seen in both freshwater (ammonia trapping) and seawater inhabiting species (vesicular transport and exocytosis).
October 2015

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23

Bradford, Emily M. "Epithelial Ion Transport and Gastrointestinal Fluid Homeostasis." University of Cincinnati / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1265985361.

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24

Harmer, Alison Rosemary. "Effects of sprint training on metabolic and ionic regulation during intense exercise in subjects with and without type 1 diabetes mellitus." Phd thesis, School of Exercise and Sport Science, Faculty of Health Sciences, 2001. http://hdl.handle.net/2123/7627.

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25

Tzavellas, Georgia. "The oxygen cost of horizontal and grade running on the treadmill with female runners." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=35203.

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The purpose of this study was to examine the vertical component of the American College of Sports Medicine (A.C.S.M.) Guidelines equation to predict the oxygen cost of grade running. The A.C.S.M. Guidelines equation is: VO$ sb2$(ml/kg.min) = 3.5 + 0.2 speed(m/min) + 0.9 (speed(m/min) * grade(frac)). Twenty-three female runners (20 to 33 years) participated in (1) a VO$ sb2$max test, (2) five 6 min running economy (RE) tests at 133 m/min, (3) five 6 min RE tests at 160 m/min, and (4) three 6 min RE tests at 186 m/min. The RE tests at 133 and 160 m/min were performed at the following grades: 0, 2.5, 5.0, 7.5, and 10.0%. The RE tests at 186 m/min were performed at 0, 2.5, and 5.0% grade. The RE tests were administered in random order. There was a linear relationship between VO$ sb2$ and horizontal running velocity with a slope of 0.20 ml/kg.m (r = 0.996; p $<$.01). There was a linear relationship between VO$ sb2$ and percent grade when running on a treadmill. The correlations for the regression equations at speeds of 133, 160, and 186 m/min were 0.90 (p $<$.01), 0.86 (p $<$.01), and 0.73 (p $<$.01), respectively. Inclusion of a grade component in the regression analysis equation increased the accuracy for predicting the VO$ sb2$ of grade running. VO$ sb2$ consumption for grade running can be predicted using the following equation: VO$ sb2$ (ml/kg.min) = 3.5 + 0.198(speed in m/min + 0.932 grade(%)) + 0.006(speed(m/min) * grade(%)). The new equation explained 99.5% of the variance (R$ sp2$) compared to the 78.0% of the variance (R$ sp2$) that was explained by the A.C.S.M. Guidelines equation.

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26

Minnenok, Lindsay R. "The matching of relative heart rate and VOp2s during graded exercise testing in healthy adults." Virtual Press, 2000. http://liblink.bsu.edu/uhtbin/catkey/1164856.

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Exercise prescription intensity is traditionally defined using a target heart rate (HR) as a surrogate measure of oxygen uptake (V02). The ACSM Guidelines recommends the use of a percentage of the maximal HRR because it is thought to match a similar percentage of maximal V02 (%V02max). However, several recent studies have challenged the notion that a given percentage of MHRR matches with the same percentage of V02max in older subjects. The purpose of this study was to assess the difference between percentages of MHRR and V02ma, and evaluate the influence of age on the agreement between these two variables across a range of exercise intensities. The sample included 530 subjects (232 men and 298 women, mean ages of 46.6 + 11.7 years and 43.3 + 11.3 years respectively) who completed a maximal treadmill test to volitional fatigue using the BSU/Bruce Ramp protocol. Heart rate and V02 data from minutes 3, 6, and 9 were converted into percentages of MHRR and V02mai,. Subjects were excluded from the analysis if they failed to achieve an RER,„a,,>1.0. Minutes 3, 6, and 9 represented 45.2 ± 11, 66.0 ± 15, and 83.1 ± 12% of VO2.x, respectively. A one-way ANOVA showed that statistically significant differences existed between the treatment means of relative intensity at minutes 3, 6, and 9 at a p-value of <0.05. The influence of age was assessed by correlation with the difference between percentages of MHRR and VO2max at minutes 3, 6, and 9. In addition, younger (<60 years of age) and older (>60 years of age) subjects were compared using an unpaired t-test. The association between age and the difference between percentages of HRR and VO2max were -0.24, -0.22, and - 0.26 at minutes 3, 6, and 9, respectively. The difference in the relative intensities of HRR and VO2max was greater for older subjects at minutes 3 and 6 (-7.0 vs. -2.2, -3.2 vs. -0.8%) but was smaller at minute 9 (-0.1 vs. -3.2%). A Scheffe post-hoc analysis was used to compare the differences between the treatment means of relative intensity. In conclusion, these results confirm the notion that percentages of MHRR. tend to underestimate percentages of VO2max in older subjects, however the differences observed within the present study were smaller than those reported previously. The small but statistically differences between the techniques would not appear to invalidate the use of percentages of MHRR as surrogate markers of percentages of VO2max in these subjects.
School of Physical Education

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27

Bjorklund, Chad Christopher. "The effects of nucleosome core particle packaging on DNA charge transport." Online access for everyone, 2006. http://www.dissertations.wsu.edu/Dissertations/Fall2006/c_bjorklund_120606.pdf.

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28

Telles, Scott Gerard. "Change in zinc permeability of lipid bilayers as a function of fluidity and oxidation." Virtual Press, 1997. http://liblink.bsu.edu/uhtbin/catkey/1061869.

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The main goal in my project was find out if the rate of zinc crossing the bilayer was either due to the fluidity of vesicles or the level of oxidation of the vesicles.To measure the oxidation a simple procedure called the TBA Test was used to measure each PC tested. The fluidity measurement was a calculation using the temperature the vesicles went from gel to liquid crystalline phase and the experimental temperature.Measuring the rate at which zinc crossed the bilayer was done using spectral changes that occur as zinc binds with APIII, a metal chelator entrapped inside the vesicles. To measure these rates we used k', the rate constant at which zinc is crossing the bilayer at a certain concentration and k, the second order diffusion rate constant which is the slope of k' vs. [Zn].The rates at which zinc was crossing the bilayer for each PC was then compared to the fluidity and oxidation levels for each PC. There was no direct correlation between the rates and fluidity but there was a good linear correlation between the rates and oxidation.So it seemed as if oxidation was the main reason zinc was crossing the bilayer so we wanted to see if our measurements could be obtained by biological cells. The comparison showed that rates obtained by biological cells can only be matched by the vesicle models when there oxidation levels are found to be high.In conclusion we believe that the reason zinc is crossing the bilayer is due to oxidation that occurs to the vesicle and as oxidation increases so do the rates at which zinc crosses the bilayer.
Department of Chemistry

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29

Fick, Christopher A. "The effect of calcium-dependent calmodulin protein kinase II (CAMKII) inhibition on insulin stimulated glucose transport in fast-twitch muscle." Virtual Press, 2002. http://liblink.bsu.edu/uhtbin/catkey/1233194.

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Insulin stimulates glucose transport into muscle cells and adipocytes via a process that involves the translocation of GLUT4 proteins from intracellular stores to the cell membrane. The pathway by which this translocation takes place has not been fully elucidated. The purpose of this study was to determine the effect of the calciumdependent calmodulin protein kinase II (CAMKII) inhibitor KN-62 on insulin stimulated 3-0-methylglucose transport in isolated rat epitrochlearis muscles. The primary finding of this investigation was that KN-62 decreased insulin stimulated glucose transport by -35%. KN-04, a structural analogue of KN-62, did not affect insulin stimulated glucose transport. Additional experiments showed that the L-type calcium (Ca 2+) channel inhibitor nifedipine inhibited glucose transport to a similar extent as KN-62 (-29%). Furthermore, no additive inhibitory effect was seen when KN-62 and nifedipine were used in combination. The results of this investigation suggest that CAMKII has a critical role in insulin stimulated glucose transport, and this role may be dependent upon L-type Cat- channel activation.
School of Physical Education

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30

Kolandavel, Maheshwaran Kollukattuvalasu. "The role of physiological motion of coronary arteries on species transport and atherosclerosis." Thesis, University of Leeds, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.441182.

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31

Burke, Mark 1975. "Factors that influence the dopamine neuron as revealed by dopamine transporter expression." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=85892.

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The primary focus of the present thesis is the exploration of factors that influence the dopamine (DA) neuron by examining the expression of the dopamine transporter (DAT), a marker of the DA neuron. The secondary focus of this thesis is on the serotonin neuron and in particular the serotonin transporter (SERT), a marker of the serotonin neuron. To this end three distinct and separate models have been employed. The goals of this thesis were: (1) to test the hypothesis that monoamine oxidase inhibition during development alters serotonergic innervation in the cortex and raphe, while not affecting relative DA innervation of nigrostriatal pathway, (2) to test the hypothesis that elevated brain levels of hypoxanthine (Hx) deleteriously affect the DA neuron, and (3) to test the hypothesis that densities of DAT and SERT in brainstem cell body regions distinguish alcohol-preferring vervet monkeys with different behavioral patterns of ethanol consumption.
Alterations in the activity of monoamine oxidase (MAO), a degradative enzyme that plays an important role in regulating levels of monoamine transmitters, may have a profound effect on brain development. The present study investigates relative DA and serotonin innervation of cortical and subcortical areas, measured by DAT and SERT densities, following MAO inhibition (A or B or A+B) in mice throughout gestation and early post-natal development. DAT binding was unaltered within the nigrostriatal pathway. The most significant finding reported here is that the combined MAO-A+B inhibition significantly reduced SERT binding by 25% in both the cortex and raphe nucleus. Lower levels of SERT binding were apparent during the early post-natal period (PND 14), a period during which pups were still exposed to MAO inhibitors in the dam's milk, but also persisted into later life (PND's 35 and 90) after inhibitors were no longer being administered. Persistent effects were restricted to cortex and raphe, suggesting a relative vulnerability of these regions to alterations in monoamine transmitter levels during development.
The second study presents data demonstrating that Hx delivered intracerebroventricularly significantly reduces the number of tyrosine hydroxylase immunoreactive cells (TH-ir) in the substantia nigra by 22% and 30%, at 7 and 21 days, respectively. After 3 days of Hx administration, striatal DA and serotonin were elevated over control levels by 22% and 25%, respectively, but returned to control levels by 7 days. The serotonin metabolite 5-HIAA was elevated after 3 days of Hx, but levels of DA metabolites were not different from control. Locomotion, a behavior thought to be related to DA transmission, was elevated following Hx treatment, as were presynaptic markers of the DA system such as DAT and TH protein levels. The persistent reduction in TH positive cell numbers suggests that Hx damages or kills DA neurons. The increase in intracellular DA at early time points suggests that Hx might interfere with DA release, possibly by temporarily inactivating DA neurons. These findings are consistent with the hypothesis that Hx, a purine significantly elevated in blood and CSF of Lesch-Nyhan patients, maybe involved in DA dysfunction.
Studies on alcohol abuse have focused on the mesolimbic DA pathway and the serotonergic influence within this pathway. Here we report that abstinent binge-drinking monkeys have significant reductions of SERT binding, and to a lesser extent, DAT binding in the midbrain region, while abstinent heavy-drinking subjects have elevated levels of DAT binding, as compared to controls. Both mesolimbic and nigrostriatal pathways are affected. CSF levels of both HVA and 5-HIAA substantiate the neuroanatomical differences between binge- and heavy-drinking vervets. Taken together, these findings provide a neurochemical profile with which to further distinguish subtypes of alcohol-preferring vervet monkeys.

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32

Iskandar, Monica. "Elevated levels of dietary zinc intake modulate the expression of CCS and intestinal zinc trafficking proteins." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=84041.

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Experiments were carried out to examine the value of CCS (copper chaperone for CuZn superoxide dismutase) as a novel biomarker of zinc-induced mild copper deficiency and to evaluate the changes in expression of zinc transporters in response to graded levels of moderately high dietary zinc. Weanling male Wistar rats were fed graded levels of zinc (30, 60, 120 and 240 mg zinc/kg diet) for 5 weeks. Results showed a dose-dependent decrease in copper content and an increase in CCS expression in tissues of rats fed the Zn-60 and Zn-120 diets. Surprisingly, rats fed the Zn-240 diet showed better copper status than rats fed the Zn-120 diet. Expression of zinc transporters was significantly upregulated in the small intestine of Zn-240 rats. Collectively, these data show that CCS is responsive to zinc-induced mild copper deficiency, and can serve as a sensitive biomarker of mild copper deficiency. The increased expression of intestinal zinc transporters expression may account for the better copper status of Zn-240 rats.

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33

Pradhan, Arati S. "Diffusion of zinc through oxidized lipid bilayers." Virtual Press, 2000. http://liblink.bsu.edu/uhtbin/catkey/1166400.

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Egg phosphatidylcholine was oxidized by atmospheric oxygen under UV light for 16 hours, and the oxidized products formed were fractionated with high-pressure liquid chromatography in reverse phase. Three fractions that appeared at retention times of 19 minutes, 21 minutes and 24 minutes respectively (fraction 19, fraction 21 and fraction 24) were isolated and stabilized by reduction with triphenylphosphine. Zinc diffusion across 1-palmitoyl-2 oleoyl-sn-glycero-3-phosphocholine (POPC) liposome bilayers mixed with the isolated oxidized fractions was measured. The rate constant for zinc diffusion through the POPC liposome was highest in fraction 19 followed by fraction 21 and fraction 24.NMR data suggests that all oxidized fractions were derived from the major egg polyunsaturated PC, 1-palmitoyl-2-linoleoyl-sn-glycero-3-phosphocholine. The primary oxidized product, fraction 24 contains a mixture of isomers in which the linoleoyl group has formed the 9-hydroxy-10,12-trans-cis diene and trans-trans diene or the 13-hydroxy12,10-trans-cis diene and trans-trans diene. The primary oxidized products on further oxidation, result in secondary oxidized products, contained in fraction 21 and fraction 19.Experimental data indicates that the major components of fraction 21 are the 9-hydroxy12,13-epoxy-l0-trans-monoene (and 13-hydroxy-9,10-epoxy-11-trans-monoene) and the major components of fraction 19 are the 9,12,13-trihydroxy-l0-trans-monoene (and 9,10,13-trihydroxy-1 l-trans-monoene).
Department of Chemistry

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34

Honess, Neil Andrew. "A study of the electroneutral cotransporters of animal cells : mechanisms of physiological control." Thesis, University of Liverpool, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321118.

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35

Marshall, Aaron. "The Biology of Mammary Gland Serotonin Synthesis and Transport." University of Cincinnati / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1251229830.

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36

Friar, Steven D. "The investigation of the zinc transport mechanism by model liposomes." Virtual Press, 1993. http://liblink.bsu.edu/uhtbin/catkey/865952.

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An ionic gradient source and a complimentary transport system regulates the flow of ions across a cell membrane. The major objective of the research focused on analyzing kinetic data to better understand the zinc transport mechanism. This study examined passive diffusion as a possible mode for zinc transport by using a liposome model system. There is a connection between bilayer fluidity (packing order of fatty acids) and rates of diffusion and this was evaluated by choosing lipids that vary with chain length and the degree of saturation or unsaturation. Zinc diffusion kinetics were monitored by observing spectral differences in the visible region of the spectrum in order to determine optimal wavelengths for the calculation of rate constants. The final objective was to calculate a permeability coefficient for each type of liposome and to make comparisons to the permeability of zinc into hepatocytes which has a permeability coefficient of about 1 X 10-7 cm/s. All liposomes used were phosphatidylcholine based. The values of the permeability coefficients for the liposomes used in this project were comparable to permeability in hepatocytes which suggest the potential importance of passive diffusion as a means for transporting biological zinc.
Department of Chemistry

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37

Wisse, Gesine Alida. "The role of sodium in the growth, respiration and membrane transport of Pseudomonas doudoroffii /." Thesis, McGill University, 1986. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=65517.

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38

Adams, Michelle R. "Importance of Niemann-Pick C1-Like 1 in Intestinal Cholesterol Transport and Vascular Reactivity." University of Cincinnati / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1329512421.

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39

Hedrick, Michael Scott. "Aspects of cardiovascular oxygen transport in vertebrates." PDXScholar, 1985. https://pdxscholar.library.pdx.edu/open_access_etds/3404.

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The hematological and rheological characteristics of blood from a number of vertebrates was compared to assess possible species differences in blood viscosity that may influence cardiovascular oxygen transport. Nucleated red blood cells (RBCs) were more viscous (measured by cone-plate viscometry) in comparison with enucleate (mammalian) RBCs at hematocrits greater than 40% when measured at equivalent temperatures. The lower viscosity of enucleate RBCs is attributed to an enhanced deformability of enucleate cells in comparison to nucleated cells.

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40

Barrento, Sara Isabel da Silva Pires Marques. "Nutritional quality and physiological responses to transport and storage of live crustaceans traded in Portugal." Doctoral thesis, Instituto de Ciências Biomédicas Abel Salazar, 2009. http://hdl.handle.net/10216/23760.

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41

Hener, Claudia [Verfasser]. "Transport mechanisms of D-amino acids and their physiological implications in Arabidopsis thaliana / Claudia Hener." Tübingen : Universitätsbibliothek Tübingen, 2020. http://d-nb.info/1215569238/34.

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42

Barrento, Sara Isabel da Silva Pires Marques. "Nutritional quality and physiological responses to transport and storage of live crustaceans traded in Portugal." Tese, Instituto de Ciências Biomédicas Abel Salazar, 2009. http://hdl.handle.net/10216/23760.

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43

Falchi, F. A. "OUTER MEMBRANE BIOGENESIS IN ESCHERICHIA COLI: GENETIC AND PHYSIOLOGICAL CELL RESPONSE TO LIPOPOLYSACCHARIDE TRANSPORT DEFECTS." Doctoral thesis, Università degli Studi di Milano, 2015. http://hdl.handle.net/2434/342548.

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The outer membrane (OM) of Gram-negative bacteria is an asymmetric bilayer formed by phospholipids in the inner leaflet and lipopolysaccharide (LPS) in the outer leaflet, with a large number of embedded or associated proteins. The primary function of this structure essential for Gram-negative viability is to establish an additional selective permeability barrier that enables the cell to maintain favourable intracellular conditions even in harsh environments and the LPS layer greatly contributes to this peculiar property. The transport of LPS to the cell surface is an essential process for OM biogenesis; the LPS transport (Lpt) system, originally identified in E. coli, is the protein machine responsible for LPS delivery from the periplasmic side of the inner membrane (IM) to the OM. It is composed of seven proteins forming a complex which spans from IM to OM. At the IM the ABC transporter LptBFG, associated to the membrane-bound protein LptC interacts with the periplasmic protein LptA that connects, through structurally conserved domains, the IM ABC transporter with the OM translocon LptDE, responsible for LPS assembly at the cell surface. In order to gain more insight in the mechanism of LPS transport and more in general in OM homeostasis we used both a genetic and a proteomic approach. The former was based on the selection of suppressors of LPS transport defects obtained with two different types of mutants. i) a quadruple non-lethal lptA mutant (lptA41) that displayed increased sensitivity to toxic compounds, and ii) a lethal deletion mutant of lptC. Genome sequencing analysis of spontaneous suppressors of lptA41 phenotype revealed two different mechanism of suppression: one mechanism involves the Mla system, a protein machinery which contributes to maintain OM asymmetry; the second mechanism involves both an intragenic mutation improving LptA41 protein stability and an extragenic mutation affecting osmoregulated periplasmic glucans (OPGs) synthesis. Viable mutants lacking lptC were obtained using a plasmid shuffling technique. Genome sequencing of such mutants revealed single amino acid substitutions at the R212 residue of the IM component LptF (lptFSupmutants). Our results suggest that LptC may serve as a chaperon of the Lpt machine assembly and/or activity rather than an essential structural component and the periplasmic domain of LptF might be implicated in the formation of the Lpt bridge. The latter approach consisted of the analysis of differential envelope proteins content of an E. coli lptC conditional expression mutant upon depletion of LptC and thus impairment of LPS transport. By two-dimensional chromatography coupled to tandem mass spectrometry (Multidimensional Protein Identification Technology, MudPIT) we identified 123 proteins whose level is significantly modulated upon LptC depletion. Most of these proteins belong to pathways that contribute to repair OM and restore its permeability barrier properties, including protein involved in maintaining OM asymmetry, in the synthesis of phospholipids and exopolysaccharides as substrate for lipid A modification enzymes, and in peptidoglycan synthesis/remodelling. Overall these data contribute to our understanding of the multiple strategies that E. coli cells may adopt to respond to perturbations of the OM permeability barrier and to restore OM functionality.

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44

Aboelkassem, Yasser. "Novel Bioinspired Pumping Models for Microscale Flow Transport." Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/28674.

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Bioinspiration and biomimetics are two increasingly important fields in applied science and mechanics that seek to imitate systems or processes in nature to design improved engineering devices. Here, we are inspired and motivated by microscale internal flow transport phenomena in insect tracheal networks, which are observed to be induced by the rhythmic tracheal wall contractions. These networks have been shown to mange fluid very efficiently compared to current state-of-the-art microfluidic devises. This dissertation presents two versions of a novel bioinspired pumping mechanism that is neither peristaltic nor belongs to impedance mismatch class of pumping mechanisms. The insect-inspired pumping models presented here are expected to function efficiently in the microscale flow regime in a simple channel/tube geometries or a complex network of channels. The first pumping approach shows the ability of inducing a unidirectional net flow by using an inelastic tube or channel with at least two moving contractions. The second pumping approach presents a new concept for directional pumping, namely ``selective pumping in a network.". The results presented here might help in mimicking features of physiological systems in insects and guide efforts to fabricate novel microfluidic devices with improved efficiency. In this study, both theoretical analysis and Stokeslets-meshfree computational methods are used to solve for the 2D and 3D viscous flow transport in several micro-geometries (tubes, channels and networks) with prescribed moving wall contractions. The derived theoretical analysis is based on both lubrication theory and quasi-steady approximations at low Reynolds numbers. The meshfree numerical method is based on the method of fundamental solutions (MFS) that uses a set of singularized force elements ``Stokeslets'' to induce the flow motions. Moreover, the passive particle tracking simulation approach in the Lagrangian frame of reference is also used to strengthen and support our pumping paradigm developed in this dissertation.
Ph. D.

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45

Zhou, Yiqing, and 周怡青. "Identification of a cellular target of triptonide and its functional study." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B46923561.

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46

Beattie, Lorraine Anne. "Electrophysiological analysis of the epithelial H+/oligopeptide transporter, PepT1." Thesis, University of Oxford, 2001. http://ora.ox.ac.uk/objects/uuid:2213d293-14cd-483b-88ab-7395e5c39b0c.

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The characteristics of transport by the epithelial, proton-coupled oligopeptide transporter, PepT1, have been investigated in PepT1 expressing Xenopus laevis oocytes using electrophysiological techniques. Membrane depolarisations and inward currents have been measured in response to various dipeptide substrates, including structurally modified and charged peptides. The latter part of this study has focussed on the role of phorbol esters on the regulation of PepT1-mediated peptide transport. I have shown that transport of neutral peptides is dependent on both pH and membrane potential. In addition, the carboxyl terminus plays an important role in substrate recognition and binding, as when blocked, the affinity of the substrate is reduced 10-fold. The importance of position of charge within a dipeptide on substrate binding has also been investigated using dipeptides where the charged amino acid residue is present at either the amino or carboxyl terminus. The results showed that the apparent order of affinity reversed upon extracellular acidification, thus charged residues within the peptide play an important role in substrate binding. The acute regulation of the oligopeptide transporter has been examined by studying the effects of phorbol esters on the transport of a neutral peptide, Gly-Gln. The active ester, PMA, was shown to decrease both the K_a and the I_max. Immunocytochemical studies have confirmed the electrophysiological findings.

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47

Flagella, Michael. "MOLECULAR AND PHYSIOLOGICAL STUDIES OF ELECTROLYTE AND FLUID TRANSPORT PERTURBATIONS IN NKCC1 AND NHE3 DEFICIENT MICE." University of Cincinnati / OhioLINK, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=ucin992433396.

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48

Al, Jahdhami Mansoor. "Physiological monitoring of welfare for conservation of Arabian oryx, Oryx leucoryx." Thesis, University of Exeter, 2010. http://hdl.handle.net/10036/3024.

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The endangered Arabian oryx, Oryx leucoryx faces a wide range of issues that potentially have adverse effects on their welfare while they are free-ranging in their natural habitat, housed in captivity for conservation breeding or when they are translocated from the wild to captivity or vice versa. Furthermore, the global increase in the number of captive Arabian oryx (currently more than 95 % of the world population of about 8000 individuals), gives rise to particular concern for their welfare and health within captive conditions. Thorough assessment of the welfare of animals involves physiological and behavioural measures. Methods for assessment of welfare in Arabian oryx have not been established and the present studies aim at establishing physiological tools for assessment of welfare. Therefore, the present studies developed and applied new methods for non-invasive assessment of welfare in the Arabian oryx (using faecal samples), and established reference values for a range of haematological, biochemical and clinical parameters. The potential disturbances in these parameters were investigated after immobilisation and tranquillisation and post- transportation. Two enzyme immuno-assays (EIA I and II) for faecal glucocorticoid metabolites (FGM) were validated by stimulation and suppression of the hypothalamic-pituitary-adrenal axis through injection of synthetic adrenocorticotropic hormone (ACTH) and dexamethasone, respectively. These studies established a lag-time of 14 ± 1 h between secretion of glucocorticoids into the blood stream and excretion of the measured FGM. Faecal incubation at 30°C for 3 days showed that EIA I measured more stable faecal glucocorticoid metabolites than EIA II, and has greater potential for application in field conditions. This method was found to be invaluable for measuring stress and hence assessment of welfare status, and its use is recommended in planning welfare improvements. Measurement of FGM successfully detected the stress of road transportation (630 km for 8-10 h), showing an increase 2 days after transport, followed by recovery to basal FGM levels after re-housing for up to 11 days. Releasing oryx to the wild, in Oman, and tracking for 11 days, after transportation 50-70 km from the captive site (Arabian Oryx Sanctuary, Jaaluni), caused an increase in FGM to the highest levels seen in these studies, and suggests a high level of stress was experienced after release of oryx. Published reference values for haematological, biochemical, hormonal and clinical parameters for Arabian oryx are limited, with little information for non-immobilised and non-tranquillised oryx or consideration of possible age and sex differences. Therefore, reference values and inter-percentile ranges (2.5 and 97.5 percentiles) were established for 32 parameters, in separate groups of male and female adult oryx, without using immobilising or tranquillising chemicals during capture. The haematological parameters investigated were white blood cell count and differentiation (%) of cell types (neutrophils, lymphocytes, monocytes, eosinophils, basophils), number of platelets, red blood cell count, haemoglobin concentration and haematocrit, erythrocyte cell volume, erythrocyte haemoglobin content and concentration, serum osmolality and ions (sodium, potassium, chloride, calcium, magnesium and phosphorus). Biochemical parameters investigated were serum urea, glucose, total protein, albumin and plasma lactate concentrations. Clinical parameters investigated were body temperature, heart and respiratory rates. Hormonal parameters measured were cortisol, free-thyroxine, free-triiodothyronine and insulin concentrations. Near basal values for serum cortisol were measured in Arabian oryx sampled within 2 min, while values were significantly higher in oryx sampled within 5-10 min. The reference values established in these studies are considered valuable tools for diagnosis of disease and physiological alterations in male and female Arabian oryx. To investigate the possible effects of the common practice of immobilisation and tranquillisation on physiological and biochemical status, two restraint chemicals (xylazine and perphenazine enanthate) were evaluated. Xylazine (an immobilising agent) caused changes in many clinical, hormonal, haematological and biochemical parameters; respiratory rate decreased by 74 %, heart rate decreased by 58 %, causing a decrease in red blood cell count, haemoglobin concentration and haematocrit, serum albumin and total protein concentration. Xylazine also induced a decrease in serum insulin, which probably caused the observed increase in serum glucose. Perphenazine enanthate (a long-acting tranquilliser) was found to have no adverse effects on most parameters, which generally remained in the reference ranges. However, a reduction in blood haematocrit and related parameters (red blood cell count and plasma haemoglobin concentration) occurred, 1-3 days after injection. The tranquilliser also plays a role in reducing stress and significantly reduced serum cortisol 2-3 days after injection in oryx held in captivity compared to oryx that received a saline (control) injection. FGM increased significantly one day after injection of perphenazine enanthate and saline, suggesting the animals were initially stressed by the handling and venipuncture, taking into consideration the lag-time from cortisol secretion to appearance of FGM. The baseline concentration of serum cortisol was used in assessing the stress caused by handling before and after transporting Arabian oryx for 630 km (8-10 h) and the acute effects of handling and injections. Increased serum cortisol was always associated with leukocytosis, neutrophilia and lymphopenia. Serum cortisol of non-transported oryx was reduced by the tranquilliser perphenazine enanthate, but transportation of tranquillised Arabian oryx during hot ambient temperature (maximum 42 °C) resulted in fatigue and prevented reaching a clear conclusion of the role of the tranquilliser in reducing transport stress. Non-tranquillised oryx transported at a maximum of 26-30 °C showed a similar level of stress as implied by the level of faecal glucocorticoid metabolites, but without fatigue. However, the tranquilliser induced calmness in Arabian oryx for up to 7 days, which facilitated capture and handling. Therefore, perphenazine enanthate has a potential to be used in the management practices, such as movement and transport of Arabian oryx. This thesis discusses the current and future welfare issues that face Arabian oryx in captivity, upon release and in the wild. Additional methods are proposed for thorough assessment and improvement of welfare to complement the methods established by the present studies.

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49

Bradley, Shannon. "Polymorphisms in the promoter region of the dopamine transporter : a candidate locus for alcohol abuse." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0029/MQ64326.pdf.

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50

Doyle, Andrew W. "Non-Classical Export of Signal Peptide-less Proteins Studied Via Sum Frequency Spectroscopy and Biochemical Techniques." Fogler Library, University of Maine, 2008. http://www.library.umaine.edu/theses/pdf/DoyleAW2008.pdf.

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Dissertations / Theses on the topic 'Physiological transport'

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