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Effects Of Aging And Strength Training On Shortening And Lengthening Muscle Actions In Women, Michelle Marie Porter
Effects Of Aging And Strength Training On Shortening And Lengthening Muscle Actions In Women, Michelle Marie Porter
Digitized Theses
There has been much research on strength changes with aging and the consequent effects of resistance training, however, relatively little is known about lengthening (eccentric; ECC) muscle actions. The purposes of these studies were to develop a method of testing and training plantar (PF) and dorsiflexion (DF) of the ankle in a standing position in order to investigate age-related and training effects on shortening (concentric; CONC) and ECC peak torque (PT) in women.;All subjects were healthy and physically active, and performed all testing and training on an isokinetic dynamometer. Strength testing was performed in both standing and supine positions at …
Expression Of Sodium Pump Subunit Genes During Mouse Preimplantation Development, Daniel James Macphee
Expression Of Sodium Pump Subunit Genes During Mouse Preimplantation Development, Daniel James Macphee
Digitized Theses
The Na,K-ATPase or sodium pump is an enzyme that is found in most animal cells. The enzyme pumps sodium and potassium ions against their concentration gradients and is hypothesized to be a mediator of fluid accumulation during mouse preimplantation development. The purpose of the present study was to determine, using reverse transcriptase-polymerase chain reaction (RT-PCR), whether all {dollar}\alpha\ (\alpha1,\ \alpha2,\ \alpha3,\ \alpha4{dollar}) and {dollar}\beta\ (\beta1{dollar} and {dollar}\beta{dollar}2) isoforms of the sodium pump were expressed during preimplantation development. Previous work by Watson and Kidder (1988) had shown that the {dollar}\alpha{dollar} subunit was localized to the basolateral domains of mural trophectoderm surrounding …
Neurophysiology Of Spared Motor Tracts In Spinal Cord Injury, Dalton Louis Wolfe
Neurophysiology Of Spared Motor Tracts In Spinal Cord Injury, Dalton Louis Wolfe
Digitized Theses
Recent experimental and therapeutic initiatives have been directed towards enhancing the survival and function of preserved central axons following spinal cord injury (SCI). The continued development of these initiatives depends largely on the sensitivity of techniques to detect the presence of residual innervation in descending motor tracts. Detection of preserved innervation in SCI patients provided the focus of the present thesis.;Preserved motor innervation was investigated in patients with established SCI using transcranial magnetic stimulation of the motor cortex to elicit motor evoked potentials (MEPs) in muscles innervated below the level of the lesion. In particular, a set of experiments was …
Role Of Nitric Oxide In Interleukin-2 Therapy-Induced Capillary Leak Syndrome, Amila Orucevic
Role Of Nitric Oxide In Interleukin-2 Therapy-Induced Capillary Leak Syndrome, Amila Orucevic
Digitized Theses
Systemic interleukin-2 (IL-2) therapy has been limited by a major side effect known as "capillary leak syndrome", characterized by retention of extravascular fluid, severe hypotension, and multiple organ system dysfunction. The present study tested the hypothesis that an overproduction of nitric oxide (NO) induced by IL-2 therapy was, at least in part, responsible for this syndrome. Studies were undertaken in healthy or C3-L5 mammary adenocarcinoma bearing C3H/HeJ mice to evaluate whether treatment with inhibitors of NO synthesis (N{dollar}\rm\sp{lcub}G{rcub}{dollar}-Methyl-L-Arginine, NMMA and N{dollar}\rm\sp{lcub}G{rcub}{dollar}-Nitro-L-Arginine methyl ester, L-NAME) can prevent IL-2 induced capillary leakage without compromising the therapeutic benefit of IL-2. Intraperitoneal IL-2 therapy …
P53-Dependent Tumorigenesis And Gene Expression In Mammalian Brain, Meyel Donald Van
P53-Dependent Tumorigenesis And Gene Expression In Mammalian Brain, Meyel Donald Van
Digitized Theses
Astrocytic gliomas are the most common brain cancers of adults. The goal of this research was to examine the molecular genetic determinants of gliomas, with particular emphasis on the tumor suppressor gene P53. First, I studied the frequency, nature and timing of P53 mutations in human gliomas. I observed that glioma-prone families do not have inherited mutations of P53, nor of the Nf1-GRD, Nf2, MTS1, MTS2, or CDK4 genes. However, a high frequency of loss of heterozygosity at chromosome 9p was noted in gliomas that cluster in families. In a second study of low-grade gliomas that progressed to higher grade …
Central Cardiorespiratory And Peripheral Metabolic Influences On Kinetics Of Oxygen Uptake In Older Humans, Philip David Chilibeck
Central Cardiorespiratory And Peripheral Metabolic Influences On Kinetics Of Oxygen Uptake In Older Humans, Philip David Chilibeck
Digitized Theses
The purpose of this thesis was to determine which factors influence oxygen uptake (VO{dollar}\sb2){dollar} kinetics during exercise in old individuals. These factors may include central {dollar}\rm O\sb2{dollar} delivery (i.e. cardiac output kinetics), the rate of O{dollar}\sb2{dollar} delivery at the exercising muscle, and the rate at which mitochondria can use O{dollar}\sb2.{dollar} Fitness level may also influence VO{dollar}\sb2{dollar} kinetics, by affecting the above factors. These factors were estimated by measuring heart rate (HR) kinetics, muscle capillarization, and citrate synthase (CS) activity, respectively, in groups of old ({dollar}\sim{dollar}65y) and young ({dollar}\sim{dollar}26y) individuals. Capillarization and CS activity of the lateral gastrocnemius were compared to …
Effects Of Industrial Effluents On Populations Of The Freshwater Mussel Lampsilis Radiata In The St Lawrence River, Lee Curtis Grapentine
Effects Of Industrial Effluents On Populations Of The Freshwater Mussel Lampsilis Radiata In The St Lawrence River, Lee Curtis Grapentine
Digitized Theses
The objective of this study was to assess the effects of industrial discharges, contaminated primarily with trace metals, on populations of Lampsilis radiata (Bivalvia: Unionidae) in the upper St. Lawrence River. Effects on shell growth were examined by (a) comparing growth curves derived from analyses of external annual rings of clams sampled from sites located upstream and downstream of four localized sources of discharges, and (b) measuring shell growth for one year from clams that were transplanted into contaminated and uncontaminated sites. Allozyme frequencies in clams from above and below discharges were determined for glucose-phosphate isomerase (GPI) and phosphoglucomutase (PGM), …
Examination Of Nucleoside Transport In The Mammalian Nervous System, Kenneth William Jones
Examination Of Nucleoside Transport In The Mammalian Nervous System, Kenneth William Jones
Digitized Theses
In rabbit and guinea pig cortical synaptosomes, the nucleoside transport inhibitors nitrobenzylthioinosine and dipyridamole were used to test the hypotheses that the nitrobenzylthioinosine-sensitive and -resistant ({dollar}\sp3{dollar}H) dipyridamole binding sites are associated with the es and ei nucleoside transporters, respectively. In addition, the hypothesis that the es and ei nucleoside transporters in rabbit cortical synaptosomes differ in their selectivity for compounds besides nitrobenzylthioinosine was tested, Nitrobenzylthioinosine-sensitive ({dollar}\sp3{dollar}H) dipyridamole binding and ({dollar}\sp3{dollar}H) nitrobenzylthioinosine binding involved the same site on the es transporter. The relative proportions and inhibitor sensitivities of nitrobenzylthioinosine-resistant ({dollar}\sp3{dollar}H) dipyridamole binding could not be correlated with nitrobenzylthioinosine-resistant nucleoside transport. This, …
Structural Basis For Human Anti-Dna Antibody Specificity, Mahmoud Mahmoudi
Structural Basis For Human Anti-Dna Antibody Specificity, Mahmoud Mahmoudi
Digitized Theses
Anti-DNA antibodies are hallmarks of SLE both in human and inbred lupus prone mice. The role of these antibodies in disease pathogenesis, particularly in glomerulonephritis has been documented. It is now well accepted that the genetic potential to generate anti-DNA antibodies also exists in the normal B cell immune repertoire. This genetic potential has been revealed by detection of anti-DNA antibodies in serum of normal individuals and by immortalizing DNA reactive B cells as hybridomas and as transformed cell lines. There is growing evidence that anti-DNA antibodies from the normal B cell repertoire and disease-associated anti-DNA antibodies share V region …
Prenatal Risk Factors For Neurological Abnormalities In The Term And Near Term Neonate, Kathleen Owen O'Connor
Prenatal Risk Factors For Neurological Abnormalities In The Term And Near Term Neonate, Kathleen Owen O'Connor
Digitized Theses
An abnormal neurological examination in the neonatal hospital stay may indicate a transient or permanent neurological disturbance. Abnormal neurological symptoms therefore place an infant at increased risk for subsequent neurological problems.;This case-control study was designed to investigate prenatal and perinatal risk factors for an abnormal neurological examination in the term infant. Infants were born between 1 January, 1988 and 30 June, 1990. The sample consisted of 222 neonates with neurological abnormalities and 666 controls who were free of such problems. Data on the prenatal histories of their mothers, course of the pregnancy, intrapartum events and status of the infant after …
Postsynaptic Cholinergic Control Of Cardiac Function In Aging, Na Su
Postsynaptic Cholinergic Control Of Cardiac Function In Aging, Na Su
Digitized Theses
The present study using isolated constant flow-perfused heart from adult (8 month-old) and aged (26 month-old) Fischer 344 rats for the first time demonstrated a striking enhancement of the negative chronotropic, inotropic and coronary vasoconstriction responses of the aging heart to postsynaptic cholinergic stimulation.;The approaches used and the results demonstrated were the following. (i) Acetylcholinesterase activity measured by the method of Ellman et al (1961) declined significantly in the atria and ventricles of the aged compared to adult rats. (ii) No age-related difference was seen in muscarinic receptor number in the atria and ventricles as assessed by {dollar}\lbrack\sp3\rm H\rbrack QNB{dollar} …
Role Of Protein Kinase C In Mediating The Effects Of Physiological And Pathophysiological Interventions In The Heart, Christopher Andrew Ward
Role Of Protein Kinase C In Mediating The Effects Of Physiological And Pathophysiological Interventions In The Heart, Christopher Andrew Ward
Digitized Theses
Protein kinase C has been implicated as a mediator of myocardial function following both physiological and pathophysiological stimuli. The purpose of the present study was to examine the functional effects of PKC in mediating phorbol esters as well as receptor-induced effects in myocardial tissues. Additionally, the possible role of PKC in mediating cardiac pathophysiology was assessed under conditions which mimicked aspects of myocardial ischemia/reperfusion. The effects of phorbol esters on cardiac function were assessed in isolated perfused guinea pig hearts. The effects of phorbol esters, acidosis/realkalinization and hydrogen peroxide were assessed in isolated guinea pig ventricular myocytes to determine PKC-dependent …
Modulation Of Experimental Allergic Encephalomyelitis In The Sjl/J Mice By Cytokines And Anti-Cytokine Antibodies, Trang Thi Duong
Modulation Of Experimental Allergic Encephalomyelitis In The Sjl/J Mice By Cytokines And Anti-Cytokine Antibodies, Trang Thi Duong
Digitized Theses
Immunization with myelin basic protein in complete Freund's adjuvant resulted in only mild chronic-relapsing experimental allergic encephalomyelitis (EAE) with very low incidence in SJL/J mice, and no disease at all in A/J, BALB/c, C3H/HeJ, DBA/2, AKR and NZW mice. However, treatment of mice with anti-IFN{dollar}\gamma{dollar} (aIFN) monoclonal antibody (mAb) at the time of immunization determined severe disease in all those strains except AKR. Similarly, the passive induction of EAE in the SJL/J mice and in two of three resistant strains examined was significantly enhanced by aIFN mAb administration. In the SJL/J mice, administration of anti-interleukin 2 (aIL2) mAb had only …
Suppression Of Eae In The Lewis Rat By Treatment With Neuroantigen-Containing Liposomes, Colleen Sheila Stein
Suppression Of Eae In The Lewis Rat By Treatment With Neuroantigen-Containing Liposomes, Colleen Sheila Stein
Digitized Theses
Treatment of Lewis rats with intracardiac injections of neuroantigen-containing liposomes significantly reduced the clinical severity of spinal cord-induced experimental allergic/autoimmune encephalomyelitis (EAE). Liposomes containing myelin basic protein (MBP), galactocerebroside (GC), or MBP + GC were effective in this respect, while liposomes containing proteolipid protein were not. The best protection was afforded by liposomes composed of whole myelin, as these ameliorated both the acute and relapsing phases of the disease, with a concomitant reduction in CNS pathology.;Neuroantigen-specific proliferative responses of lymphnode cells (LNC) taken from liposome-treated rats were markedly attenuated in comparison to control LNC, while delayed type hypersensitivity (DTH) reactions …
A Genetic Analysis Of Folate Transport In Chinese Hamster Ovary Cells, T Michael Underhill
A Genetic Analysis Of Folate Transport In Chinese Hamster Ovary Cells, T Michael Underhill
Digitized Theses
Chinese Hamster Ovary cells that are about 50x more resistant to the cytotoxic action of methotrexate than wild-type cells were deficient in the ability to take up methotrexate. In the absence of any exogeneous folates these cells require 100-250x the level of folinic acid as do wild-type cells to support growth at a similar level. Two classes of mutants were distinguishable by their revertability for growth on folinic acid and ability to take-up folic acid. Revertants derived from one class were similar to wild-type cells in their ability to grow in medium containing low levels of folinic acid and in …
Determinants Of Critical Power And Anaerobic Work Capacity In Young And Elderly Men, Thomas James Overend
Determinants Of Critical Power And Anaerobic Work Capacity In Young And Elderly Men, Thomas James Overend
Digitized Theses
Determinants of critical power (CP, the theoretical maximal rate of non-fatiguing work) and anaerobic work capacity (AWC, a finite energetic reserve from intra-muscular sources) were determined in young (n = 13, 24.5 y) and elderly men (n = 12, 70.7 y). The purposes of the four studies were to: (1a) determine and compare CP and AWC in young and elderly men; (1b) determine if CP does represent a true maximal rate of non-fatiguing work; (2) determine thigh component cross-sectional areas (CSA) and volumes; (3) determine the strength and strength/CSA ratios of the knee extensors and knee flexors; and (4) identify …
Natural Lta Tumor Cell Resistance To Malignant Conversion By Oncogenesras Andmyc, Alan Bradley Tuck
Natural Lta Tumor Cell Resistance To Malignant Conversion By Oncogenesras Andmyc, Alan Bradley Tuck
Digitized Theses
A tumorigenic, non-metastatic murine fibroblast cell line (LTA) was here used to study aspects of natural cellular resistance to induction of progression to malignancy. The nature of LTA cell growth was established by testing both in vitro and in vivo. In vitro growth showed some but not all characteristic features of transformation (eg. cells showed little contact inhibition of cell growth and were able to multilayer, but were not serum independent). In vivo tumor growth was that of a benign (non-metastatic) fibrosarcoma. Attempts were made to induce LTA cell progression to malignancy by both epigenetic and genetic means. Treatment of …