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1
Ali, Cairo F. "Animal rights and animal research." The Ohio State University, 1987. http://rave.ohiolink.edu/etdc/view?acc_num=osu1371556393.
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Schuessler, Thomas F. "A computer controlled research ventilator for small animals /." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=69704.
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Understanding the mechanical properties of the respiratory system is an important task in pulmonary physiology. Current research often involves small mammals (mice, rats or guinea pigs) which are easily obtained in large numbers as pure bred strains, thus allowing statistically reliable results with minimal inter-animal variation to be obtained. However, due to the small flow amplitudes involved, the input impedance of common flow measurement devices is often too low to reliably measure tracheal flow. Furthermore, experimental setups are usually very limited in the types of volume, pressure or flow perturbations they can apply to the respiratory system. The computer controlled research ventilator for small animals described here overcomes both problems. Tracheal flow is estimated from the position of the ventilator piston and the pressure within the cylinder. Furthermore, the setup is capable of applying any desired volume perturbation with a bandwidth up to 55 Hz.
3
Siegel, Angeline M. "Unspoken connections| Scientists' intersubjective experiences with animals." Thesis, Saybrook University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3711355.
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<p> Little is known about the scientist-animal relationship; therefore, the aim of this study was to learn how moments of intersubjectivity, or "oneness" are created and experienced by scientists. It is by appreciating the risks and vulnerabilities intrinsic to human-animal relationships that propel the present investigation. The current cultural bias of valuing objectification and detachment as the predominant form of scientific investigation overlooks relational subtleties intrinsic to deriving meaning from humananimal studies. By examining scientists and their descriptions of intersubjectivity with their animal participants, a greater understanding of society's philosophical and ethical deliberations on the human-animal relationship may be revealed. An exploratory, sequential mixed-method design was utilized to phenomenologically examine intersubjectivity, as well as to measure the prevalence of its dimensions within the larger academic population. Phenomenological analysis from ten interviews identified humananimal intersubjectivity as having four significant phases: <i>joint mindfulness, synchronized embodiment, intrinsic belonging </i>, and <i>transcendental awareness</i>. Spearman correlational analysis from fifty-four responses to the online survey supported these findings, as well as identified a potential link with the variables of proximity (r<sub> s</sub> = .469, p < .05, n=25), closeness (r<sub>s</sub> = .483, p < .01, n=25), similarity (r<sub>s</sub> = .483, p < .01, n=25) and embodied awareness (r<sub>s</sub> = .421, p < .01, n=25) that account for variation in the scientific population. When examining past behavior as it related to current scientific practices, gender differences emerged that resemble those reported by neuroanatomical studies. Lastly, further mixed analysis identified academic and cultural risks that were met by employing concealment and silencing strategies. These results add valuable depth in the interpretation of intersubjectivity and its relationship with scientific behavior, as well as insight into the role of intersubjectivity within ethical and philosophical debates.</p>
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Lyons, Daniel Louis. "Protecting animals versus the pursuit of knowledge : the evolution of the British animal research policy network." Thesis, University of Sheffield, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.434527.
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Lombard, Chereé. "Animal welfare and the law : towards legal regulation of the welfare of laboratory animals in South Africa / Chereé Lombard." Thesis, North-West University, 2012. http://hdl.handle.net/10394/8718.
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The current legal framework pertaining to animals does not sufficiently address the welfare of animals. The Animal Protection Act 71 of 1962 does not specifically regulate the welfare of animals contained in research laboratories. Animals utilized for experimental research purposes endure tremendous “unnecessary suffering” due to legislative inaptitude. Experimental animals suffer inherent abuses associated with experimental research because of the methods, procedures and processes relevant to the experiments. The most controversial method of experimental research is vivisection. The method of vivisection is not only invasive but also causes “unnecessary suffering” to animals. The non-inherent abuses animals suffer during confinement in a laboratory solely relates to uncontrolled and unregulated conduct of staff.
Continuing the application of the current legislative framework may also be detrimental to the health and well-being of humans. Animals are specifically utilized as objects of science in research laboratories. The data obtained from research experiments conducted on animals are for the benefit of humankind rather than the animals. Scientific research concluded that not only are invasive methods of research conducted on live animals generally regarded as useless but extrapolating data from animals to humans can also be misleading, unnecessary and dangerous. False results and questionable methodologies are some of the other problems that seem to require urgent attention. Ethically, neither human nor animal should be utilized at the expense of the other and therefore it would be reasonable to recommend that legislative reform takes place.
The human perception of animals in terms of the relationship we have with them is the reason why legislative inaptitude in terms of animal welfare exists. The current approach followed is the philosophy of Utilitarianism. Utilitarians believe that neither humans nor animals have rights but interests. Utilitarianism focuses on the permissibility of an act (the use of animals) by weighing the benefits of such an act to the costs suffered because of such act. If the benefits outweigh the costs suffered, the act is permissible. The application of Utilitarianism seems to be the crux of our legislative inaptitude. The human perception and view of animals must therefore be re-directed to develop a sufficient legal framework in terms of animal welfare. A solution offered is to apply an alternative interpretation to the concept of “dignity” (capabilities approach) and progressive realisation. In terms of this solution a species capabilities in terms of its value, capabilities and worth are considered. Inherent to its value, capabilities and worth, is its “dignity”. Once the alternative interpretation of “dignity” is acknowledged, the progressive realisation of its interests can be achieved.<br>Thesis (LLM)--North-West University, Potchefstroom Campus, 2013
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Melonas, Alexander Paul. "Situated Animals: A Critique of Social Constructivist Excesses in Political Theory." Diss., Temple University Libraries, 2015. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/321722.
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Political Science<br>Ph.D.<br>In this dissertation I explore the ramifications of political theory being freed from two opposed extremes of biologism and social constructivism because, ultimately, the human animal is both a biological creature and capable of becoming. While it has been highly significant for humanistic scholars to challenge the governing authority of the "hard sciences" as the prime site of legitimacy in modern scholarship, the position of critique has transformed into one of outright and unqualified hostility. I resist this commitment to show that work at the intersection of the human biological sciences and political theory need not amount to political conservatism or pessimism. To this end, I address two questions with the aim of (re-)situating the human animal as a common property in political theory. First, I explore and challenge the commitments that inform the strict social constructionist thesis. This move leads to a second consideration: what questions are open if we see the problem not as biology, but as biological determinism? I make four arguments in this dissertation. First, I use Ernst Cassirer to show that "human" and "animal" can be integrated in a philosophical anthropology in a constructive way, one that avoids the reductionism implied in the term "animal" (or biological creature) and the naiveté of conceiving of human beings as though they are distinct from or wholly independent of nature. Second, I use Marxist materialism to integrate the human biological sciences with a meaningful theory of human freedom. Third, I work at the intersection of contemporary political theories of identity and the human biological sciences to reconcile the effects of "predispositions" with the effects of our social identities. I do so in a way that resists essentialism. Finally, I use feminist scholarship to argue that the human biological sciences cannot be used to justify hierarchy, or rather, that "hard science" doesn't in any meaningful sense say anything at all about equality.<br>Temple University--Theses
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Mota, Karine Alves Gonçalves. "Experimentação animal no Brasil: uma abordagem normativa acerca da criação, manutenção e pesquisa com animais." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-15052018-115616/.
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O estudo se desenvolveu de forma a analisar a regulamentação normativa acerca da criação, manutenção e do uso de animais em pesquisa no Brasil, com ênfase nos roedores no que tange às instalações físicas de biotério, observado ser o animal mais facilmente utilizado em pesquisa. Motivada pelo fato da República Federativa do Brasil ter por fundamento a Dignidade da Pessoa Humana, que coloca o homem em situação singular ao amparo legal, e, essencialmente pela proteção ao meio ambiente onde se inclui o direito dos animais, em especial a vedação de maus tratos. Encontrando-se a ética no uso de animais em pesquisa, o fator determinante para o reconhecimento e garantia dos direitos dos envolvidos nesse processo. Neste aparato, a problemática proposta pôde ser representada pela seguinte pergunta: A legislação do Brasil é suficiente e eficiente para regulamentar a experimentação científica e assegurar a proteção dos direitos dos animais? O objetivo foi analisar as normas gerais jurídico-positivas aplicáveis ao uso de animais em pesquisa no Brasil.<br>The study was developed from the analysis of the normative regulation about the use of animals in researches in Brazil and motivated by the fact that the Federative Republic of Brazil is based on the Dignity of the Human Person - which places man in a unique situation under legal protection - and essentially by the protection of the environment, including the right of animals - especially the prohibition of ill-treatment. Finding the ethics in the use of animals in researches and tests is the determining factor for the recognition and guarantee of the rights of those involved in this process. In this apparatus, the problematic proposed by the article could be represented by the following question: Is Brazil\'s legislation enough and efficient to regulate scientific experimentation and assure the protection of animal rights? The purpose was to analyze the general legal-positive and ethical standards applicable to the use of animals in brazilian researches.
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Himmler, Brett T., and University of Lethbridge Faculty of Arts and Science. "The effect of playful experiences on the plasticity and metaplasticity of the brain." Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Neuroscience, 2011, 2011. http://hdl.handle.net/10133/3081.
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The influence of play behavior on the brain was investigated through plasticity and metaplasticity methodology. Regions in both cortical and sub-cortical areas were investigated. Animals in both studies either experienced play with juvenile partners or did not experience play by being paired with an adult. Play experience alone was shown to affect the plasticity in the prefrontal cortex, although it did not show structural changes to sub-cortical regions. If animals were given nicotine after play experiences, the affects of play in the prefrontal cortex were abolished. In addition, playful behaviors appear to prime some sub-cortical regions of the brain for expression of later plasticity. Thus, play appears to alter the structure of multiple brain areas, but do so in different ways.<br>ix, 67 leaves ; 29 cm
9
Layton, Raymond J. "Macroinvertebrate colonization and production in new experimental ponds." Diss., This resource online, 1989. http://scholar.lib.vt.edu/theses/available/etd-03042009-040552/.
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Pinto, Renan Mercuri [UNESP]. "Componentes principais na seleção de animais em pesquisas experiementais." Universidade Estadual Paulista (UNESP), 2014. http://hdl.handle.net/11449/110369.
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000788566.pdf: 21022540 bytes, checksum: d6b25eb7f401d2f54ea65ced1d872cd6 (MD5)<br>Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)<br>Devido à falta de conhecimento estatístico, muitos pesquisadores utilizam métodos empíricos ou subjetivos para a tomada de decisão, ignorando o processo de casualização e, consequentemente, influenciando seus resultados, nomeadamente no processo de homogeneização de amostras, imprescindível para a randomização em pesquisas que envolvem animais como unidade experimental. esse processo, tem-se o hábito errôneo de fazê-lo de maneira fragmentada ou intencional, utilizando-se de apenas um parâmetro conveniente para classificar o grupo como homogêneo. Fato que, além de resultar numa homogeneização viesada e inadequada, favorece a possibilidade de descartar animais por um simples valor espúrio do que por semelhança ou dessemelhança biológica. Tendo em vista essa problemática, este trabalho sugere um critério estatístico multivariado elaborado com a finalidade de rescindir o paradigma biológico que avalia o animal (unidade experimental) de maneira fragmentada. Nesse critério, considera-se a situação biológica do animal como um todo, já que o organismo reage de maneira conjunta a qualquer intervenção ou tratamento, ou seja, analisam-se conjuntamente todos os parâmetros do animal, pois estes são correlacionados, e a melhor forma de entender o comportamento animal está expressa em um conjunto de informações numéricas que represente suas características biológicas. Esse modelo foi aplicado a um conjunto de dados de animais induzidos à estenose aórtica que possibilitou a identificação de seis espúrios ao grupo. Sua importante contribuição explica-se pelo melho!amento na qualidade de homogeneização e por assegurar com máxima acurácia a inclusão de animais semelhantes e pequena frequência de descartes, motivando maximizar o lote homogêneo para posterior submissão ao delineamento experimental por processo simples de casualização dos tratamentos.<br>Due to lack of statistical knowledge, many researchers use empirical or subjective methods to make a decision, ignoring the randomization process and thus influencing its results, particularly in the process of samples homogenization, essential for randomization in research involving animals as experimental unit. In this process, researchers have the erroneous habit of doing it in a fragmented or intentional manner, using only one convenient parameter to classify the group as homogeneous. Fact that besides resulting in inadequate homogenization, favors the possibility of discarding animals by simple spurious value than by bialogical similarity or dissimilarity. Considering this problem, this work suggests a multivariate statistical criterion of high accuracy developed in order to rescind the biological paradigm that evaluates the animal (experimental unit) in a fragmented manner. In this criterion, it is considered the animal biological condition as a whole, since the body reacts conjointly to any intervention ar treatment, in other words, all the parameters of the animal are analyzed together, as they are correlated, and the best way to understand animal behavior is expressed in a set of numerical information that faithfully represents its biological characteristics. This model was applied to a data set of animais with aortic stenosis and allowed the identification of six animais spurious to the group. It's remarkable contribution is explained by the improvement in the quality of homogenization and by ensuring with maximum accuracy the inclusion of similar animais and small frequency discards, motivating to maximize the homogeneous batch for subsequent submission to the experimental design by simple randomization process of the treatments.<br>FAPESP: 12/11976-6
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Geoffroy-Dallery, Laetitia. "Attitudes of Clinical Psychologists Towards the Reporting of Nonhuman Animal Abuse." Antioch University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=antioch1533029757149596.
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Hines, Dustin J., and University of Lethbridge Faculty of Arts and Science. "The role of cues and the hippocampus in home base behaviour." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2004, 2004. http://hdl.handle.net/10133/646.
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The thesis examines the ability of animals to construct a home base. The home
base is a point in space where animals rear, groom, and circle and is a primary element in
organized spatial behaviour (Eilam and Golani 1989). Once animals establish a home
base, they make outward trips and stops, and after a series of trips and stops they return
again to the home base. The home base behaviour of animals acts as a platform for asking
questions about the cognitive organization of an environment. The thesis describes five
main findings. Control and hippocampectomized animals use (1) proximal and (2) distal
cues to form a home base and organize their behaviour. (3) Control and olfactory
bulbectomized animals form home bases in the dark where as hippocampectomized
animals are impaired suggesting self-movement but not olfactory cues play a role in
home base behaviour. A final set of experiments demonstrated that control and
hippocampectomized animals learn the position of (4) proximal and (5) distal cues so that
in the cue's absence, animals still form a home base at that position. The demonstration
that a central feature of exploratory behaviour, establishing a home base, is preserved in
hippocampectomized rats in relation to proximal, distal, and conditioned visual cues -
reveals that exploratory behaviour remains organized after hippocampal lesions. The
inability of hippocampectomized rats to form a virtual home base in the absence of visual
cues is discussed in relation to the idea that the hippocampus contributes to inertial
behaviour that may be dependent upon self-movement cues.<br>xv, 232 leaves : ill. ; 29 cm.
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Nemati, Farshad, and University of Lethbridge Faculty of Arts and Science. "Contribution of brain with or without visual cortex lesion to exploratory locomotion in the rat." Thesis, Arts and Science, 2008. http://hdl.handle.net/10133/665.
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Over the past five decades spatial behavior has been a subject of research
interest in psychology and neuroscience, in part based on philosophical theories
of mental spatial representations. In order to continue uncovering the facts
regarding spatial behavior, the focus of this thesis was on the contribution of
entry point and visual inputs to the organization of exploratory locomotion and
spatial representation in the rat. Despite the contribution of the hippocampus to
spatial abilities, the exploratory locomotion is still visually organized in rats with
damage to the hippocampus. On the other hand, recent studies have
demonstrated a contribution of visual areas to the spatial ability of the rat.
Nevertheless, the contribution of visual cortex to the organization of exploratory
locomotion has not been studied in an open field. The experiments in this thesis
were designed to characterize the organization of exploratory locomotion to the
point of entry and/or visual cues. Rats were started from the edge or center of an
open table near or on which a salient object could be placed. The main findings
were that rats organized their exploratory locomotion to their point of entry and
modified their behavior as they encountered objects. Also, rats with damage to
visual cortex displayed an extra-attachment to the visual objects and in contrast
to controls did not expand their exploratory locomotion with time. The results are
discussed with respect to the centrality of the entry point in the organization of
exploratory locomotion and the neural network that control visual exploration in
the rat.<br>xiii, 220 leaves : ill. ; 29 cm. --
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Fang, Yu-Hua. "Quantification of Pharmacokinetics in Small Animals with Molecular Imaging and Compartment Modeling Analysis." Cleveland, Ohio : Case Western Reserve University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=case1238635584.
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Thesis (Ph.D.)--Case Western Reserve University, 2009<br>Department of Biomedical Engineering Abstract Title from OhioLINK abstract screen (viewed on 10 April 2009) Available online via the OhioLINK ETD Center
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Kaluthota, Chinthaka Dhanyakumara. "The organization and variability of song in Northern House Wrens (Troglodytes aedon parkmanii)." Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Psychology, c2013, 2013. http://hdl.handle.net/10133/3353.
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Hypothesized functions of complex song in birds include a role in mate attraction
and territory defense and, through regional dialects, in genetic substructuring of
populations and speciation. The necessary first step in testing such functions is a detailed
characterization of song organization and variability. This is provided for the Northern
House Wren (Troglodytes aedon), a species noted for complex song, but lacking detailed
descriptions. The species was studied at two sites in Alberta with a sample of 15,000
songs from 15 males. Males sang in long bouts, each song composed of multiple syllable
types and repeated many times before switching. The population repertoire of 27
syllables was almost entirely shared, but used to construct novel repertoires of up to 200
different song types for individual males without evidence of a ceiling. Additional
flexibility and constraints in song construction are discussed in view of the above noted
functions of song complexity.<br>x, 111 leaves : ill., maps ; 29 cm
16
Bagchi, Tamishraha. "Immune mechanisms in murine brucellosis : studies with strain RB51, a rough mutant of Brucella abortus /." Diss., This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-09162005-115020/.
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Germain, P. "HUMANS, ANIMALS, AND PETRI DISHES: BIOMEDICAL MODELING BETWEEN EXPERIMENTATION AND REPRESENTATION." Doctoral thesis, Università degli Studi di Milano, 2014. http://hdl.handle.net/2434/234133.
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The use and evaluation of biomedical models – in vitro and in vivo models of diseases – is discussed among scientists, philosophers and science policy-makers, in an attempt to maximize the efficiency and relevance of research and minimize unnecessary moral costs. However, such evaluations raise several methodological issues and have generally been hampered by a lack of attention to the precise functions played by biomedical models. For if biomedical models are ultimately expected to inform us about human pathologies, they seldom do so in isolation, and get there through a wide variety of ways. An epistemological understanding of this process is therefore a precondition for their evaluation, and this thesis
is an attempt at building such an epistemology.
Several of the examples used come from cancer research, especially xenograft models and models used in the context of large-scale drug screenings. Another important set of examples come in vitro models, with a particular focus on disease modeling using induced pluripotent stem cells.
I argue that the notion of model, if conceived as to apply to biomedical models, conflates into that of experimental system. I therefore propose an account of biomedical models that does not presuppose a fundamental divide between modeling and experimentation. I show that biomedical models are not simply scaled-down versions of their target, but instead projections of their target in a different space of representation. I argue for an instrumental role of biomedical models, and use this role to explore the diversity of proximal functions fulfilled by biomedical models. I propose the notion of distributed modeling to draw attention to the relations between model systems, and illustrate this by analyzing the interplay between in vitro and in vivo models. Finally, I explore the implications of this account for the evaluation of biomedical models, and more broadly for the topic of scientific representation.
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Quiggle, David Douglas. "The effects of R-flurbiprofen in reducing tumors in a multiple intestinal neoplasia mouse model." CSUSB ScholarWorks, 2001. https://scholarworks.lib.csusb.edu/etd-project/2009.
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The design of the proposed study was to administer R-FB to 72-day old Min/+ mice for up to 42 days. In order to capture the process of tumor reduction, animals were necropsied at various time points. At each time point animals were evaluated for tumor loads and presence of apoptotic cells along the small intestine. Studies have shown that when R-flurbiprofen (R-FB) is administered in the Min/+ mouse model it can cause the prevention and regression on intestinal tumors.
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Gonzalez, Claudia L. R., and University of Lethbridge Faculty of Arts and Science. "An analysis of poststroke motor dysfunction and cerebral reorganization in rats." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2004, 2004. http://hdl.handle.net/10133/15.
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This thesis investigates the behavioural and anatomical correlates of recovery from motor cortex damage in rats. The effectiveness of behavioural, pharmacological, and regenerative treatments was investigated using models of focal stroke. Chronic bilateral motor deficits were found after motor cortex damage induced by various methods. These behavioural deficits were similar in severity and duration although they were correlated with different patterns of reorganization seen in Golgi-stained tissue. Animals with motor cortex injury benefited from postinjury olfactory stimulation, chronic administration of nicotine, and infusions of epidermal growth factor followed by erythroprotein. Different mechanisms of plasticity in remaining cortical circuits are discussed as possible candidates responsible for the behavioural improvement. The current thesis expands the current knowledge of the effects of adult cortical damage to ares critical to motor control. It may also stimulate research on therapies and possible mechanisms that might enhance recovery after stroke.<br>xviii, 299 leaves : ill. (some col.) ; 29 cm.
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Faraji, Jamshid, and University of Lethbridge Faculty of Arts and Science. "Structural alterations in the hippocampus and spatial behavior by stress in male and female rats : protections, and recovery in water-based and dry-land tasks." Thesis, Lethbridge, Alta : University of Lethbridge, Faculty of Arts and Science, 2008, 2008. http://hdl.handle.net/10133/725.
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Stress-related cognitive changes are still a matter of debate. In some
particular neuropathological conditions such as focal ischemia, cognitive
functions have been shown to be significantly impaired. These conditions,
however, may be improved by some factors such as steroid hormones. The
purpose of the current thesis was to assess the structural and functional effects
of corticosterone-related experiences on the hippocampus before and after
endothelin-1 (ET-1)-induced stroke. We found corticosterone-related experiences
enhance the hippocampal recovery, and improve its function in both wet and dryland
tasks after ET-1-induced focal stroke. Structural and functional effects of
such experiences prior to the focal ischemia in the hippocampus, however,
showed that stress, not corticosterone is a strong inhibitor for hippocampal
recovery.<br>xii, 252 leaves : ill. ; 29 cm. --
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Lowings, Michael D., and University of Lethbridge Faculty of Arts and Science. "Epigenetic regulation of stroke recovery : changes in DNA methylation and micro-RNA regulation following stroke and EGF/EPO neurogenesis therapy." Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Biological Sciences, c2010, 2010. http://hdl.handle.net/10133/2570.
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Stroke is one of the most common, and damaging, neurological afflictions.
Stroke causes widespread and variable chronic effects, due to the limited regenerative
ability of the adult brain. Altered gene expression induces neuronal changes
necessary for plasticity-dependent recovery, effects which can be enhanced by growth
hormone-based pharmaceuticals. These processes are driven by alterations in the
informational capacity of the genome – changes driven by epigenetic regulators.
Following experimental strokes, and treatment with EGF and EPO, this study shows
that two epigenetic regulatory mechanisms, DNA methylation and microRNA
regulation, are significantly altered, both in treated and untreated animals.
Specifically, treatment induces a net global suppression of miRNA activity, which
appears to modify the physical behaviour of neurons in domains ranging from
plasticity and memory formation, growth and replication, and potentially even to
neurological disease signalling. The confirmation of epigenetic alterations following
a stroke indicates a future role for epigenetic neuro-pharmacology in stroke
management.<br>x, [99] leaves : ill. (some col.) ; 29 cm
22
Spanswick, Simon, and University of Lethbridge Faculty of Arts and Science. "Adrenalectomy-induced neuronal degeneration : development of a novel animal model of cognitive dysfuntion and neurogenic treatment strategies." Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Neuroscience, 2010, 2010. http://hdl.handle.net/10133/2587.
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Long-term adrenalectomy (ADX) results in a specific loss of dentate gyrus granule cells in the hippocampus of adult rats, occurring over a period of weeks to months. This loss of granule cells results in cognitive deficits in a number of tasks that depend on intact hippocampal function. The gradual nature of ADX-induced cell death and the ensuing deficits in cognition are similar to those experienced by patient populations suffering from a variety of pathological conditions. Here we present an animal model by which we use ADX to produce a loss of granule cells within the hippocampus of rats. We also provide experimental evidence for a treatment strategy by which the lost granule cells may be replaced, with the goal of functional recovery in mind.<br>xii, 191 leaves : ill. (chiefly col.) ; 28 cm
23
Van, Vuuren Derick. "Postconditioning the isolated perfused rat heart : the role of kinases and phosphatases." Thesis, Stellenbosch : Stellenbosch University, 2008. http://hdl.handle.net/10019.1/20864.
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Thesis (MScMed)--Stellenbosch University, 2008.<br>ENGLISH ABSTRACT: It has recently been observed that the application of multiple short cycles of reperfusion and ischaemia, at the onset of reperfusion, elicits cardioprotection against injury due to prior sustained ischaemia. This phenomenon has been termed “postconditioning” (postC) and is of special interest due to its clinical applicability. Although much work has been done to delineate the mechanism of protection, there is still controversy regarding the precise algorithm of postC, the importance of the reperfusion injury salvage kinases (RISK), as well as uncertainty about the possible role of p38 MAPK and the protein phosphatases in postC cardioprotection.
The aims of this study were therefore:
I. To develop and characterise a cardioprotective postC protocol in the ex vivo rat heart, using both the retrogradely perfused and working heart models.
II. To characterise the profiles of PKB/Akt, ERK p42/p44 and p38 MAPK associated with the postC intervention.
III. To investigate the possible role of the serine/threonine protein phosphatases type 1 and type 2A (PP1 and PP2A) in the mechanism of postC.
Hearts from male Wistar rats were perfused in both the retrograde Langendorff (at a perfusion pressure of 100 cmH2O and diastolic pressure set between 1 and 10 mmHg) and working heart models (preload: 15 cmH20 and afterload: 100 cmH20). Several different postC protocols were tested for their cardioprotective effect, as analysed by infarct size (IFS; determined by triphenyltetrazolium chloride (TTC) staining) and functional recovery. Experimental parameters tested were the number of cycles (3,4 or 6), the duration of the cycles (10, 15, 20 or 30 seconds), the method of application (regional or global) and temperature during the intervention (36.5 or 37 °C). Different sustained ischaemic insults were also utilised: 35 minutes regional (RI) or 20, 25, 30 and 35 minutes global ischaemia (GI).
Hearts treated with a cardioprotective postC intervention or standard reperfusion after sustained ischaemia, were freeze-clamped at 10 and 30 minutes reperfusion in both perfusion models. Tissue samples were then analyzed using Western blotting, probing for total and phosphorylated PKB/Akt, ERK p42/p44 and p38 MAPK. The contribution of PKB/Akt and ERK p42/p44 activation to cardioprotection was also investigated by administration of inhibitors (A6730 and PD098059 respectively) in the final 5 minutes of ischaemia and the first 10 minutes of reperfusion, in the presence and absence of the postC intervention. The effect of these inhibitors were analyzed in terms of IFS and kinase profiles.
The possible role of the phosphatases in postC was investigated by observing the effect of cantharidin (a PP1 and PP2A inhibitor) treatment directly before sustained ischaemia (PreCanth) or in reperfusion (PostCanth), in the presence and absence of postC, on IFS and kinase profiles.
A postC protocol of 6x10 seconds global reperfusion / ischaemia, at 37°C, was found to give the best and most consistent reduction in infarct size in both the Langendorff (IFS in NonPostC: 47.99±3.31% vs postC: 27.81±2.49%; p<0.0001) and working heart (IFS in NonPostC: 35.81±3.67% vs postC: 17.74±2.73%, p<0.001) models. It could however only improve functional recovery in the Langendorff model (after 30 minutes GI: rate pressure product (RPP) recovery: NonPostC = 12.27±2.63% vs postC = 24.61±2.53%, p<0.05; and after 35 minutes GI: left ventricular developed pressure (LVDP) recovery: NonPostC = 28.40±7.02% vs postC = 48.49±3.14%, p<0.05). This protection was associated with increased PKB/Akt (NonPostC: 0.88±0.26 AU (arbitrary unit) vs postC: 1.65±0.06 AU; p<0.05) and ERK p42 (NonPostC: 2.03±0.2 AU vs postC: 3.13±0.19 AU; p<0.05) phosphorylation. Inhibition of PKB/Akt activation with A6730 (2.5 μM) abrogated the infarct sparing effect of postC.
Administration of cantharidin, either before of after ischaemia, in the absence of postC, conferred an infarct sparing effect (IFS in PreCanth: 15.42±1.80%, PostCanth: 21.60±2.79%; p<0.05) associated with an increase in the phosphorylation of MAPK p38 (administration before ischaemia: NonCanth: 1.52±0.26 AU vs PreCanth: 2.49±0.17 AU, p<0.05; and administration after ischaemia: NonCanth: 5.64±1.17 AU vs PostCanth: 10.69±1.29 AU, p<0.05) and ERK p42 (when administered in reperfusion; NonCanth: 2.24±0.21 AU vs PostCanth: 3.34±0.37 AU; p<0.05). Cantharidin treatment combined with the postC intervention did not elicit an additive infarct sparing effect (postC: 17.74±2.72%, PreCanth-postC: 13.30±3.46% and PostCanth-postC: 15.39±2.67%). In conclusion: a postC protocol of 6x10 seconds global ischaemia / reperfusion, at 37°C, confers the best infarct sparing effect in both the Langendorff and working rat heart models. This protection is associated with ERK p42 and PKB/Akt phosphorylation, although only PKB/Akt is necessary for cardioprotection. We could not find evidence for PP1 and PP2A involvement in postC, although inhibition of these phosphatases per se does elicit an infarct sparing effect. The latter observation suggests that phosphatase activation during ischaemia / reperfusion is potentially harmful.<br>AFRIKAANSE OPSOMMING: Dit is onlangs waargeneem dat toediening van meervoudige siklusse herperfusie / iskemie, met die aanvang van herperfusie, die hart teen iskemie / herperfusie beskadiging beskerm. Hierdie verskynsel, bekend as postkondisionering (postC), geniet tans baie aandag vanweë die kliniese toepaslikheid van die ingreep. Ten spyte van intensiewe navorsing om die betrokke meganisme van beskerming vas te stel, is daar steeds kontroversie oor die presiese algoritme van die ingreep, asook die betrokkenheid van die sogenaamde iskemie herperfusie oorlewings kinases (RISK). Daar bestaan ook onsekerheid oor die rol van die stres-kinase, p38 MAPK, asook die proteïen fosfatases in die meganisme van beskerming teen iskemiese besering.
Hierdie studie het dus drie doelstellings gehad:
I. Ontwikkeling van ‘n postC protokol wat beskerming ontlok in die rothart ex vivo, deur gebruik te maak van beide die retrograad geperfuseerde ballon model, asook die werkhart model.
II. Analiese van die profiele van die kinases PKB/Akt, ERK p42/p44 en p38 MAPK tydens herperfusie van postC en kontrole (NonPostC) harte.
III. Ondersoek na die moontlike rol van die serien / treonien proteïen fosfatases tipe 1 en tipe 2A (PP1 en PP2A) in die meganisme van postC beskerming.
Harte van manlike Wistar rotte is geperfuseer in beide die retrograad geperfuseerde ballon (d.i. die Langendorff) model (teen ‘n konstante perfusie druk van 100 cmH20 en ‘n diastoliese druk gestel tussen 1 en 10 mmHg), asook die werkhart model (teen ‘n voorbelading van 15 cmH20 en ‘n nabelading van 100 cmH20). Verskeie moontlike postC protokolle is getoets vir hul vermoë om kardiobeskerming te ontlok, in terme van funksionele herstel en infarktgrootte (IFS), soos bepaal deur trifenieltetrazolium chloried (TTC) kleuring. Die eksperimentele veranderlikes tydens die postC protokol wat ondersoek is, sluit in: die aantal siklusse (3, 4 of 6), die duur van die siklusse (10, 15, 20 of 30 sekondes), die wyse van postC toediening (streeks of globaal) en laastens die temperatuur tydens die ingreep (36.5 of 37 °C). Daar is ook gebruik gemaak van verskillende periodes iskemie: 35 minute streeks iskemie (RI), asook 20, 25, 30 en 35 minute globale iskemie (GI). Na 10 of 30 minute herperfusie is harte wat blootgestel is aan ‘n kardiobeskermende postC ingreep of gewone standaard herperfusie na iskemie, in beide perfusie modelle, gevriesklamp. Die weefsel proteïen-inhoud is verder geanaliseer deur van die Western blot tegniek gebruik te maak vir bepaling van die totale en fosforileerde vlakke van PKB/Akt, ERK p42/p44 en p38 MAPK. Die funksionele belang van PKB/Akt en ERK p42/p44 is verder ondersoek deur die effek van ‘n geskikte inhibitor (onderskeidelik A6730 en PD098059, toegedien tydens die laaste 5 minute van iskemie en die eerste 10 minute van herperfusie), in die teenwoordigheid en afwesigheid van die postC ingreep, op infarktgrootte en kinase aktiwiteit te monitor.
Die moontlike rol van proteïen fosfatases in postC is ondersoek deur die effek van cantharidin (‘n PP1 en PP2A inhibitor) op infarktgrootte en kinase profiele te ondersoek. Cantharidin is óf onmiddelik voor iskemie óf tydens herperfusie toegedien, in die aan – en afwesigheid van die postC ingreep.
Daar is bevind dat ‘n postC protokol van 6x10 sekondes globale iskemie / herperfusie, teen 37°C, die mees effektiewe en konstante verlaging in infarktgrootte teweeg gebring het in beide die ballon model (IFS in NonPostC: 47.99±3.31% vs postC: 27.81±2.49%; p<0.0001), asook die werkhart (IFS in NonPostC: 35.81±3.67% vs postC: 17.74±2.73%, p<0.001). Funksionele herstel kon egter slegs ontlok word in die ballon model (na 30 minute GI: tempo druk produk (RPP) herstel: NonPostC = 12.27±2.63% vs postC = 24.61±2.53%, p<0.05; en na 35 minute GI: linker ventrikulêre ontwikkelde druk (LVDP) herstel: NonPostC = 28.40±7.02% vs postC = 48.49±3.14%, p<0.05). Die infarkt-besparende effek van postC was geassosieer met ‘n toename in die fosforilasie van beide PKB/Akt (NonPostC: 0.88±0.26 AU (arbitrêre eenhede) vs postC: 1.65±0.06 AU; p<0.05) en ERK p42 (NonPostC: 2.03±0.2 AU vs postC: 3.13±0.19 AU; p<0.05). Inhibisie van PKB/Akt met A6730 (2.5 μM) het die infarkt-besparende effek van postC opgehef.
Inhibisie van PP1 en PP2A opsigself, deur toediening van cantharidin óf voor óf na iskemie (in die afwesigheid van postC), het ‘n infarkt-besparende effek ontlok (IFS in PreCanth: 15.42±1.80%, PostCanth: 21.60±2.79%; p<0.05). Hierdie kardiobeskerming was geassosieer met ‘n toename in die fosforilasie van beide p38 MAPK (met toediening voor iskemie: NonCanth: 1.52±0.26 AU vs PreCanth: 2.49±0.17 AU, p<0.05; en toediening na iskemie: NonCanth: 5.64±1.17 AU vs PostCanth: 10.69±1.29 AU, p<0.05), asook ERK p42, indien cantharidin toegedien is tydens herperfusie (NonCanth: 2.24±0.21 AU vs PostCanth: 3.34±0.37 AU; p<0.05). Kombinasie van cantharidin behandeling met postC toediening kon egter nie ‘n kumulatiewe infarkt-besparende effek uitlok nie (postC: 17.74±2.72%, PreCanth-postC: 13.30±3.46% en PostCanth-postC: 15.39±2.67%).
In samevatting: ‘n PostC protokol van 6x10 sekondes globale iskemie / herperfusie, teen 37°C, ontlok die mees effektiewe infarkt-besparende effek in beide die ballon, sowel as die werkhart modelle. Alhoewel hierdie beskerming geassosieer is met ‘n toename in die fosforilasie van beide PKB/Akt en ERK p42/p44 tydens herperfusie, is dit slegs PKB/Akt wat van funksionele belang is in die meganisme van kardiobeskerming. Ons kon geen bewyse vind vir die betrokkenheid van PP1 en PP2A in postC beskerming nie, alhoewel inhibisie van hierdie fosfatases opsigself infarkt-besparend is. Laasgenoemde waarneming toon dat fosfatase aktivering tydens iskemie / herperfusie skadelike gevolge mag hê.
24
Frede, David. "A tale of two zoos : a study in watching people watching animals." Thesis, The University of Sydney, 2007. http://hdl.handle.net/2123/3762.
Full textAbstract:
Zoological gardens, or zoos, keep and display wild animals, mainly for the purposes of education, conservation and biological research. However, it is evident that a significant component of zoos is the vast number of people who visit them, since without the support of visitors, zoos would not be financially viable and would cease to exist. This research investigates the behaviours of these visitors and develops an understanding of their awareness relating to what they see and do while they are in the zoo, along with their motivations for visiting. The study focuses on two major metropolitan zoos in Australia: Adelaide (in South Australia) and Taronga (in Sydney, New South Wales). A brief historical account contextualises changes, raising awareness of the significance of visitors to the livelihood of zoos. More and more zoos are integrating into their management routines different programmes that relate to the care and welfare of the animals. Despite recent growth in scientific attention, which has focused on human-animal relationships, little research has been conducted relating to the human visitor in the zoo. To date, decisions made by administrators have been based upon assumptions of the visitors’ understanding of the work of zoos rather than on actual quantitative findings. This empirical research is significant in that it uses both quantitative and qualitative methods to appraise factual data and information. The data from unobtrusive tracking observations at different exhibits, combined with the results of questionnaire surveys, are used to explore and assess the perceptions of visitors. In developing a demographic profile of the people who visit zoos, this work considers the motivations and the frequency of visitors. Various factors that influence the viewing patterns of visitors are explored to assess the popularity of exhibits, and the perceptions of visitors relating to animals and enclosures are investigated, to assess the diverse levels of satisfaction. Case studies explore the perceptions and understandings of visitors towards the use of enrichment items, the use of signs and labels, and a hypothetical approach to the feeding of carnivores in zoos. The results are important in that they contribute essential knowledge that describes the perceptions of a wide range of people who visit zoos, along with their expectations, since it is crucial for these institutions to maintain their popularity with the public.
25
Frede, David. "A tale of two zoos : a study in watching people watching animals." University of Sydney, 2007. http://hdl.handle.net/2123/3762.
Full textAbstract:
Doctor of Philosophy<br>Zoological gardens, or zoos, keep and display wild animals, mainly for the purposes of education, conservation and biological research. However, it is evident that a significant component of zoos is the vast number of people who visit them, since without the support of visitors, zoos would not be financially viable and would cease to exist. This research investigates the behaviours of these visitors and develops an understanding of their awareness relating to what they see and do while they are in the zoo, along with their motivations for visiting. The study focuses on two major metropolitan zoos in Australia: Adelaide (in South Australia) and Taronga (in Sydney, New South Wales). A brief historical account contextualises changes, raising awareness of the significance of visitors to the livelihood of zoos. More and more zoos are integrating into their management routines different programmes that relate to the care and welfare of the animals. Despite recent growth in scientific attention, which has focused on human-animal relationships, little research has been conducted relating to the human visitor in the zoo. To date, decisions made by administrators have been based upon assumptions of the visitors’ understanding of the work of zoos rather than on actual quantitative findings. This empirical research is significant in that it uses both quantitative and qualitative methods to appraise factual data and information. The data from unobtrusive tracking observations at different exhibits, combined with the results of questionnaire surveys, are used to explore and assess the perceptions of visitors. In developing a demographic profile of the people who visit zoos, this work considers the motivations and the frequency of visitors. Various factors that influence the viewing patterns of visitors are explored to assess the popularity of exhibits, and the perceptions of visitors relating to animals and enclosures are investigated, to assess the diverse levels of satisfaction. Case studies explore the perceptions and understandings of visitors towards the use of enrichment items, the use of signs and labels, and a hypothetical approach to the feeding of carnivores in zoos. The results are important in that they contribute essential knowledge that describes the perceptions of a wide range of people who visit zoos, along with their expectations, since it is crucial for these institutions to maintain their popularity with the public.
26
Molina, Leonardo A. "Alteration of neural dynamics in the rat medial prefrontal cortex by an NMDA antagonist." Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Neuroscience, c2012, 2012. http://hdl.handle.net/10133/3264.
Full textAbstract:
NMDA receptor antagonists such as Ketamine and PCP are potent psychoactive drugs used recreationally. This class of drug induces a number of phenomena in humans similar to those associated with schizophrenia including reduced selective attention, altered working memory, thought disorders and hallucinations. These psychotomimetic drugs have thus been used as a longstanding model to study this disease in animals. Importantly, such animal models allow for recording of brain activity using invasive techniques that are inappropriate in humans. Previous electrophysiological studies have shown that MK-801, a potent non-competitive NMDA receptor antagonist, increases gamma-frequency oscillations and produces a state of disinhibition in the prefrontal cortex of rats wherein the activity of putative excitatory pyramidal neurons increases while the activity of putative inhibitory interneurons decreases. These features are relevant to schizophrenia because molecular evidence suggests dysfunction of inhibitory cortical interneurons, while electroencephalographic recordings show altered gamma-frequency oscillations in this disease. It has been hypothesized that the disinhibited cortical state produces “noisy” information processing, but this has not been directly observed in the interaction of neuronal firing in either humans or animal models. We therefore tested this hypothesis by examining the synchronization of neural activity in the NMDA receptor antagonist model of schizophrenia. We used high-density electrophysiological recordings in the medial prefrontal cortex of freely moving rats before and after systemic injection of MK-801. Analysis of these recordings revealed that drug administration: (i) increases gamma power in field potentials in a manner dissociated from increased locomotion; (ii) does not change the gamma power in multi-unit activity; (iii) decreases spike synchronization among putative pyramidal neurons in the gamma range (30ms), and despite of this it (iv) does not change the synchronization between gamma-range field potentials or between sum-of-spikes and field potentials. These effects in synchronization may be revealing of potent cognitive effects associated with NMDA receptor antagonism, and may reflect impaired communication processing hypothesized to occur in schizophrenia.<br>xi, 42 leaves : ill. ; 29 cm
27
Rakai, Brooke D., and University of Lethbridge Faculty of Arts and Science. "Experience dependent plasticity of stroke outcome." Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Neuroscience, c2008, 2008. http://hdl.handle.net/10133/2518.
Full textAbstract:
Stroke outcome is highly variable. Experiments in this thesis test the hypothesis that experience prior to a stroke is an important variable in the manifestation of stroke. Optokinetic tracking was used to evaluate the effects of visual cortex stroke and MCA occlusion in rats. Normal laboratory rats showed a small, but significant decrease in tracking thresholds following visual cortex stroke. Animals with developmental visuomotor experience or reach training experience in adulthood, however, had tracking thresholds which were substantially increased, and the effects of visual cortex strokes were greater. MCA occlusions did not affect tracking behaviour. These data indicate that specific experiences engage neural plasticity that can alter brain function. These changes can, in turn, affect the behavioural manifestation of a stroke. Understanding the effect that environmental experience has on stroke outcome promises to enable better characterization of strokes, and set appropriate behavioural baselines for the measurement of recovery of function.<br>vi, 135 p. : ill. ; 29 cm
28
Clark, Callie Anne Marie, and University of Lethbridge Faculty of Arts and Science. "Sound-induced behavioural activation in the normal and haloperidol-treated rat." Thesis, Lethbridge, Alta. : University of Lethbridge, Canadian Centre for Behavioural Neuroscience , c2008, 2008. http://hdl.handle.net/10133/1293.
Full textAbstract:
Diseases of the central and peripheral nervous systems affect one in five people in North America. Parkinson’s disease (PD) is the second most common neurodegenerative disease, after Alzheimer’s disease, and occurs in approximately 1% of the general North American population. PD is a progressive movement disorder that is characterized by resting tremor, rigidity, bradykinesia (slowness of movement) or akinesia (absence of spontaneous movement), as well as postural instability. Current treatment of PD is symptom-based, and no pharmacological treatment currently exists to slow the progression of bradykinesia and akinesia. In fact, pharmacological therapies produce motor side effects in advanced stages of the disease. Given the difficulty in initiating and controlling movement as PD advances, and the ineffectiveness of medical therapies after prolonged treatment, physical and music therapies can be used to supplement classical therapies. Listening to, and performing, music affects a number of neural regions, including those that mediate motor behaviour, arousal or activation, and emotion. Despite anatomical connections between the auditory and motor systems at the level of the spinal cord, brain stem, midbrain, and cortex, the neural and behavioural mechanisms for sound-induced activation remains unclear. It is known, however, that PD patients recruit external sensory stimuli to improve movement. The aim of the current research was to create an animal model of sound-induced activation and to test the effect of previous motoric experience on the potency of auditory stimuli. To investigate behavioural activation in the normal and haloperidol-treated rat, two tasks were used: 1) orienting responses were analyzed for movement components in saline and haloperidol treated rats
v
to find out if rats responded in the same to a variety of naturally produced and generated activating sounds, and 2) a grid climbing task allowed for the righting components of naïve and familiar cataleptic rats to be compared. Our findings revealed that familiar auditory cues could release parkinsonian rats from catalepsy. The current research supports the theory that auditory stimulation retains “special access” to motor regions otherwise impaired in PD and likely bypasses basal ganglia circuitry to normalize movement through alternative pathways.<br>xiv, 142 leaves : ill. (some col.) ; 29 cm
29
Zelinski, Erin L., and University of Lethbridge Faculty of Arts and Science. "Impacts of chronic and acute phase-shifting in male and female rats." Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Neuroscience, c2010, 2010. http://hdl.handle.net/10133/2590.
Full textAbstract:
This thesis assessed the impacts of acute and chronic phase-shifting on learning
and memory in male and female rats. Previous research has revealed impaired retention
immediately following circadian disruption and on the acquisition of new associations.
However, whether behaviour resumes normality following circadian re-entrainment is
unresolved. Following circadian re-entrainment, retention of pre-phase-shift acquired
associations on Morris water task (MWT) and a visual discrimination task designed on
the 8-arm radial maze were tested. Subsequently, an extradimensional set shift (EDS)
using the 8-arm radial maze was performed. Acute circadian disruption negatively
impacted retention in males and females, but only male rats without running wheels
exhibited impairment following chronic phase-shifting on MWT performance. Retention
on the visual discrimination task was impaired following chronic, but not acute, circadian
disruption. Chronic, but not acute, phase-shifting negatively impacted performance on the
EDS. Generally, phase-shifting produced differential negative impacts on cognitive
function in rats.<br>xiv, 181 leaves : ill. (some col.) ; 29 cm
30
Hardy, Jared C., and University of Lethbridge Faculty of Arts and Science. "Behavioral correlates of unilateral dopamine depletion in the MPP+ rat model of Parkinson's Disease." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2007, 2007. http://hdl.handle.net/10133/385.
Full textAbstract:
Conventional cylinder test measures have limited sensitivity in determining hemiparkinson rat forelimb use asymmetry and approximating substantia nigra (SN) dopaminergic neuron loss. This thesis investigates which cylinder test measures of hemiparkinson rat forelimb use asymmetry best predict methamphetamine-induced rotation and extent of dopaminergic neuron loss. Long-Evans rats were cylinder-tested after unilateral 1-methyl-4-phenylpyridinium (MPP+)-induced SN dopamine depletion. Time and count of numerous forepaw wall contact patterns were documented for MPP+ hemiparkinson rats and sham-operated controls using frame-by-frame video analysis, then regressed against methamphetamine-induced rotation and tyrosine hydroxylase-positive neuron depletion. Severely dopamine-asymmetric rats initiated movements slower and less often with the contralateral-to-lesion forepaw, indicating that the cylinder test may be used to assess Parkinson Disease motor impairments of bradykinesia and akinesia. Several new time and count asymmetry measures may improve cylinder test sensitivity to hemiparkinson-specific forelimb use asymmetries.<br>xi, 103 leaves : ill. ; 29 cm.
31
Driscoll, Ira, and University of Lethbridge Faculty of Arts and Science. "The aging hippocampus : a multilevel analysis in the rat." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2005, 2005. http://hdl.handle.net/10133/12.
Full textAbstract:
The purpose of the current thesis was twofold: (1) to examine various factors that might be contributing to age-related learning and memory deficits specifically related to the hippocampus, and (2) to validate our rat model of aging, employing a multilevel analysis. We found age-related deficits on both spatial and non-spatial hippocampus-dependent taks that were accompanied by structural alterations observed in vivo (volune, but not neuronal metabolic function) and post mortem (neuronal density and neurogenesis, but not synaptic or mitochondrial density). Furthermore, our results suggest that the observed hippocampal structural changes, named decreased volume and neurogenesis, predict learning and memory deficits, and both can be accounted for by neurogenic reduction. In addition, the above-mentioned pattern of age-related deficits closely resembles that seen in humans, suggesting the present rat version of aging to be a very useful model for investigating hippocampal aging in humans.<br>iii, 236 leaves : ill. (some col.) ; 29 cm.
32
Sparks, Fraser T. "Interactions of the hippocampus and non-hippocampal long-term memory systems during learning, remembering, and over time." Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Neuroscience, c2012, 2012. http://hdl.handle.net/10133/3116.
Full textAbstract:
The hippocampus and non-hippocampal long-term memory systems each have the capacity
to learn and express contextual fear memory. How these systems interact during learning
and remembering revolves around hippocampal mediated interference, where the hippocampus
dominates for both the acquisition and expression of long-term memory. Hippocampal
interference during learning can be overcome by modifying learning parameters
such that learning is distributed across multiple independent sessions. The standard view of
the role of the hippocampus in long-term memory retrieval is that it is temporally limited,
where recently acquired memory is dependent on hippocampal function though as a memory
ages, dependency is transferred to other memory systems by a process called systems
consolidation. Distributed training demonstrates that learning parameters create a memory
that is resistant to hippocampal damage. We find little evidence to support temporally based
systems consolidation, and present data that supports the view that if the hippocampus is
initially involved in learning a memory, it will always be necessary for accurate retrieval
of that memory. A critical assessment of the rat literature revealed that initial memory
strength, and/or lesion techniques might be responsible for the few studies that report temporally
graded retrograde amnesia using contextual fear conditioning. Our experiments
designed to directly test these possibilities resulted in flat gradients, providing further evidence
that the hippocampus plays a permanent role in long-term memory retrieval. We
propose and assess alternatives to the standard model and conclude that a dual store model
is most parsimonious within the presented experiments and related literature. Interactions
of the hippocampus and non-hippocampal systems take place at the time of learning and
remembering, and are persistent over time.<br>xvi, 161 leaves : ill. (some col.) ; 29 cm
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Bolstad, K. S. "Systematics of the Onychoteuthidae Gray, 1847 (Cephalopoda: Oegopsida) a thesis submitted to the Earth & Oceanic Sciences Research Institute, Auckland University of Technology in fulfilment of the requirements for the degree of Doctor of Philosophy, supervised by Dr Steve O'Shea, 2008." Click here to access this resource online, 2008. http://hdl.handle.net/10292/414.
Full text
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Silasi, Gergely, and University of Lethbridge Faculty of Arts and Science. "Novel treatments for inducing cortical plasticity and functional restitution following motor cortex stroke." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2005, 2005. http://hdl.handle.net/10133/278.
Full textAbstract:
Stroke remains a leading cause of disability in the western world, with symptoms ranging in severity from mild congnitive or motor impairments, to severe impairments in both cognitive and motor domains. Despite ongoing research aimed at helping stroke patients the disease cannot be prevented or cured, therefore a large body of research has been aimed at identifying effective rehabilitative strategies. Based on our understanding of normal brain function, and the meachanisms mediating the limited spontaneous recovery that is observed following injury, factors that promote brain plasticity are likely to be effective treatments for stroke symptoms. The current thesis investigated three novel treatments (COX-2 inhibitor drug, vitamin supplement diet, and social experience) in a rat model of focal ischemia in the motor cortex. All three treatments have been previously shown to alter plasticity in the normal brain, however the current experiments show that the treatments have differential effects following stroke. The COX-2 inhibitors provided limited improvement in functional performance, whereas the vitamin supplement treatment had no effect. Social experience on the other hand was found to block the usually observed spontaneous improvements following the stroke. These results suggest that factors that alter dendritic plasticity may in fact serve as effective stroke treatments depending on the site and the mechanisms whereby the plastic changes are induced.<br>ix, 149 leaves : ill. ; 29 cm.
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Gharbawie, Omar A., and University of Lethbridge Faculty of Arts and Science. "Modeling middle cerebral artery stroke in rats : an examination of the skilled reaching impairments." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2006, 2006. http://hdl.handle.net/10133/388.
Full textAbstract:
Middle cerebral artery (MCA) stroke can produce chronic incapacitating motor
impairments. Understanding the neural basis of the motor syndromes is complicated by
the diversity of neural structures damaged but the problem can be addressed in laboratory
rats by inducing selective infarcts. Nevertheless, the motor syndromes that ensue from
stroke in rats remain poorly understood and undermine its potential as a model for
clinical stroke. The objective of the present thesis was to document the skilled reaching
impairments from neocortical and subcortical MCA infarcts in rats. In addition, the
integrity of the motor system components spared by the infarct was assessed
neurophysiologically and neuroanatomically. Characteristic reaching impairments
emerged from each infarct but there were also some overlapping features that might be
explained by neural dysfunction extending beyond the boundaries of the infarct. The
present studies showed that the laboratory rat is an ideal animal model for studying
stroke, which should be of interest to both clinical and research scientists studying stroke.<br>xiii, 345 leaves : ill. ; 29 cm. + 1 CD-ROM
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Cardiff, James W. "Experienced-induced immediate early gene expression in hippocampus after granule cell loss." Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Neuroscience, c2012, 2012. http://hdl.handle.net/10133/3356.
Full textAbstract:
Adrenalectomy
(ADX)
has
been
shown
to
cause
selective
degeneration
of
granule
cells
in
the
dentate
gyrus
(DG).
This
occurs
due
to
the
reduction
of
corticosterone
(CORT)
and
behavioural
deficits
are
associated
with
the
loss
of
these
neurons.
Dentate
lesions
and
cell
loss
associated
with
ADX
have
been
shown
to
effect
behaviour
in
a
number
of
spatial
tasks.
In
contras,
it
has
been
shown
granule
cell
loss
does
not
affect
the
specificity
of
place
cells
in
CA3
and
CA1.
We
used
the
ADX
model
to
examine
the
role
of
DG
granule
cells
plays
in
representing
space
using
immediate
early
gene
(IEG)
activation
in
the
principal
hippocampal
subfields
after
exploration
of
novel
environments.
Rats
were
allowed
to
free
explore
multiple
novel
environments
and
then
the
mRNA
for
the
IEG
Homer
1a
(H1a)
was
used
as
a
marker
of
neural
activity.
After
degeneration
of
approximately
half
of
the
DG
granule
cells
we
found
a
significant
increase
in
number
of
active
cells
in
the
DG,
CA3
and
CA1
in
ADX
animals.
The
results
indicate
a
reduction
in
granule
cells
causes
a
dramatic
increase
in
the
proportion
of
remaining
DG
granule
cells
in
response
to
exploration.
The
change
in
DG
activation
disrupts
the
representations
in
CA3
and
CA1
and
thereby
affects
behaviour.<br>vii, 60 leaves : ill. (some col.) ; 29 cm
37
Silva, Tatiana Tavares da. "Inovação biomédica e o animal não humano em pesquisa: controvérsias científicas e reflexões éticas para contribuição na implementação de políticas públicas de técnicas substitutivas ao uso de animais em pesquisa, ensino e indústria." Universidade do Estado do Rio de Janeiro, 2014. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=7187.
Full textAbstract:
A experimentação animal é uma prática extremamente incorporada à ciência biomédica moderna, com raízes desde a Antiguidade, mas que foi cada vez mais se desenvolvendo, adquirindo características bem definidas. O animal não humano, no contexto da experimentação, é um ser vulnerado, enclausurado dentro de uma estrutura muito bem definida, que mantém um discurso focado na excelência do modelo do animal na pesquisa e testes, com o objetivo de garantir a manutenção dessas práticas. No entanto, ao analisarmos os dados científicos obtidos com a experimentação animal, que visa primariamente um possível benefício humano, assim como as argumentações éticas relativas ao respeito à vida e ao sofrimento do animal envoltas nesta situação, a argumentação ética prepondera sobre uma base científica cuja eficácia é também extremamente questionável. Partindo de uma análise crítica da aplicação do modelo animal como padrão da pesquisa científica e da concepção ética do reconhecimento da vulnerabilidade do animal não humano na experimentação, propomos que esta reflexão colabore com políticas públicas que incentivem e implementem as técnicas substitutivas ao uso de animais não humanos em pesquisa, testes da indústria e ensino na área biomédica no Brasil.<br>Animal experimentation is an extremely convenient inserted in modern biomedical science, with roots from antiquity, but it was increasingly developing, acquiring well-defined characteristics. The non-human animal in the context of trials is a hacked being, enclosed within a well defined structure that holds a speech focused on excellence in animal model in research and testing, with the goal of maintaining these practices. However, when analyzing the scientific data obtained from animal experiments, which primarily targets a possible human benefit, as well as the ethical arguments concerning respect for life and the suffering of animals wrapped in this situation, the ethical argument outweighs scientific basis whose effectiveness is also extremely questionable. Based on a critical analysis of the application of animal model as the standard of scientific research and the ethical conception of recognition of the vulnerability of non-human animal experimentation, we propose that this reflection collaborate with public policies that encourage and implement the substitute for use of non-human animals in research, testing and education industry in Brazil biomedical techniques.
38
Yim, Tonia Tan-Ling, and University of Lethbridge Faculty of Arts and Science. "Multiple-object memory requires the hippocampus." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2007, 2007. http://hdl.handle.net/10133/678.
Full textAbstract:
This thesis investigates the role of the hippocampus in object memory. Currently,
the role of the hippocampus in object recognition is unclear, with some studies
demonstrating a delay-dependent impairment after hippocampal damage, others showing
no impairment. The present thesis used the novel object recognition task and its variants
to investigate various types of object memory in hippocampal lesion rats. In the first
study, impairments were observed in discriminating object order and associating objects
with contexts, while no impairment was observed in novel object recognition. In the
second study, it was found that encountering another object shortly prior to or after
encountering a target object impairs the recognition of the target object. In a control
procedure, encountering a novel context either shortly before or after encountering the
target object did not impair object recognition. In sum, in the absence of the hippocampus,
object memory becomes vulnerable to interference, rendering rats unable to discern
memories of multiple objects. The present thesis concludes that the hippocampus
discriminates multiple objects via pattern separation. A stimulus-response model relating
the role of the hippocampus to object memory is proposed.<br>vii, 150 leaves : ill. ; 29 cm. --
39
Richards, Sonja. "An animal model of autism : remediation with tactile stimulation." Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Neuroscience, 2011, 2011. http://hdl.handle.net/10133/3126.
Full textAbstract:
This thesis examines both behavioral and anatomical effects of prenatal exposure of
Valproic Acid (VPA) on Long Evans rats. Tactile stimulation (TS) is then used to
investigate its’ effect on remediating any abnormalities VPA may produce. Several
behavioral tests were done to assess the behavioral effects of VPA and TS. It was found
that VPA had an effect of many of the tasks, whereas, TS had almost none with the
exception of an effect on females in the elevated plus maze. However, anatomical data
showed that TS had a profound effect on neuronal branch order, cell complexity, and
spine density in pyramidal neurons in the medial prefrontal cortex, the orbitofrontal
cortex and the amygdala. Where VPA decreased the above in all of these areas, TS
increased neuronal complexity in the aforementioned structures. This study demonstrates
that prenatal exposure to VPA is a viable model of autism in rats and that TS has
significant anatomical effects in these animals as well as in control animals<br>xi, 98 leaves; 29 cm
40
Kanchwala, Mustafa Ashiq Hussain. "A Miniature Wireless Neural Recording and Stimulating System for Chronic Implantation in Freely Moving Animals." Case Western Reserve University School of Graduate Studies / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=case153079448199171.
Full text
41
Liu, Xingbo. "Cardiac Calcium Channel Expression in Heart Specific Growth Hormone (GH) Receptor Gene Disrupted Mice and Bovine GH Mice." Ohio University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1397650862.
Full text
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Merrifield, Matthew, and University of Lethbridge Faculty of Arts and Science. "Radiation-induced deregulation of PiRNA pathway proteins : a possible molecular mechanism underlying transgenerational epigenomic instability." Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Biological Science, c2011, 2011. http://hdl.handle.net/10133/2617.
Full textAbstract:
PiRNAs and their Piwi family protein partners are part of a germline specific epigenetic regulatory mechanism essential for proper spermatogenesis, silencing of transposable elements, and maintaining germline genome integrity, yet their role in the response of the male germline to genotoxic stress is unknown.
Ionizing radiation (IR) is known to cause transgenerational genome instability that is linked to carcinogenesis. Although the molecular etiology of IR-induced transgenerational genomic instability is not fully understood, it is believed to be an epigenetically mediated phenomenon. IR-induced alterations in the expression pattern of key regulatory proteins involved in the piRNA pathway essential for paternal germline genome stability may be directly involved in producing epigenetic alterations that can impact future generations.
Here we show whole body and localized X-irradiation leads to significant altered expression of proteins that are necessary for, and intimately involved in, the proper functioning of the germline specific piRNA pathway in mice and rats. In addition we found that IR-induced alterations to piRNA pathway protein levels were time and dose dependent.<br>ix, 123 leaves : ill. (some col.) ; 29 cm
43
Corley, Sean Ryan. "Cholinergic basal forebrain involvement in the acquisition of differential reinforcement of low rate responding tasks in rats." CSUSB ScholarWorks, 2005. https://scholarworks.lib.csusb.edu/etd-project/2780.
Full textAbstract:
It was hypothesized that 192 IgG-saporin lesions of the basal forebrain cholinergic system (BFCS) would disrupt differential reinforcement of low rate (DRL) learning in an uncued DRL task, but would not impair acquisition and performance in the cued version of the task. Results suggest that BFCS lesions impair vigilance to the external cues despite continued practice in the cued DRL, whereas continuous attention to internally produced cues recovers with extended practice in the uncued DRL.
44
Nall, Gregory Allen. "An alternative model of chimpanzee social structure, with implications for phylogenetic models of stem-hominid social structure." Virtual Press, 1992. http://liblink.bsu.edu/uhtbin/catkey/845924.
Full textAbstract:
The following research paper was concerned with five basic objectives:(1) outlining the major theoretical and methodological approaches used in the reconstruction of early hominid social behavior/social structure as a context in which to view Richard Wrangham's and Michael Ghiglieri's phylogenetic models of stem-hominid social structure.(2) examining Wrangham's and Ghiglieri's models of stem-hominid and chimpanzee social structure.(3) indicating how theoretical and methodological aspects of structure essentially represent an extension of the theoretical and methodological approaches the same researchers applied to their models of chimpanzee social structure.(4) addressing the theoretical and methodological deficiences of Wrangham's and Ghiglieri's models of chimpanzee social structure.(5) providing suggestions for improved phylogenetic models of early hominid social structure.The first objective was achieved by: (a) reviewing Tooby and Devore's (1986) and Wrangham's (1986) evaluations of the major theoretical approaches and methodologies used in the reconstruction of hominid social behavior/structure (b) defining, classifying and evaluating Wrangham's and Ghiglieri's phylogenetic approaches within this context.The second objective was accomplished by outlining, analyzing, and comparing/contrasting Wrangham's and Ghiglieri's phylogenetic models of stem-hominid social structure (i.e.Wrangham 1986; Ghiglieri 1987, 1989) and Wrangham's and Ghiglieri's models of chimpanzee social structure (i.e. Wrangham 1975, 1979; Ghiglieri 1984, 1985, 1987, 1989).The third objective was achieved by recognizing how Wrangham and Ghiglieri used/stressed principles and concepts derived from evolutionary biology and/or behavioral ecology to develop their models of stem-hominid and chimpanzee social structure. This analysis showed that Wrangham's models of social structure were more favorably inclined toward the method of behavioral ecology than Ghiglieri's models, which favored a sociobiological paradigm. Furthermore, although neither researcher relied exclusively on the above theoretical approaches, the main thrust of their argument often centered around it. For instance, Wrangham's analysis of chimpanzee social structure (Wrangham 1975, 1979) indicated that the ultimate cause of that structure was ecological i.e., patchy food distribution leads to wide female dispersal for optimal foraging efficiency, which in turn favors a male kin breeding group that can maintain a territority that includes several individual female ranges. In contrast, Wrangham's phylogenetic model of the social structure of the stem-hominid (Wrangham, 1986) suggested that phylogenetic inertia may be partially responsible for the shared social features found among African Hominoidea. However, in the same work, Wrangham also suggested that further socioecological analysis of African apes may indicate whether food distribution and its effects on female dispersion/association may partially explain conservative African ape social features.Ghiglieri's phylogenetic model of the stem-hominid (1987, 1989), on the other hand, explained the conservative social features of bonobos, common chimpanzees, and hominids to be primarily a product of phylogenetic inertia and sexual selection. Furthermore, for Ghiglieri the most important sexual selection variable was a male communal reproductive strategy. This, according to Ghiglieri, is the ultimate cause of social structure. Notably, Ghiglieri (1984, 1985) had earlier stressed the overiding importance of a male communal reproductive strategy but was less dogmatic in his insistence that chimpanzees had essentially solved their ecological problems (e.g. that they had solved the food distribution problem by fusion-fission sociality; predators were never a real problem). Nevertheless, Ghiglieri's earlier position similarily expressed the idea that a communal reproductive strategy constituted the ultimate cause of social structure.The fourth objective was accomplished by presentation of an alternative model of chimpanzee social behavior which suggested that structure; the effect of phylogenetic inertia on social structure; chimpanzee social structure is the combined product of ecological and sexual selection forces: female optimal foraging, male mating strategies, and predator pressure. The model was considered by the author to be unique in that it integrated essential aspects of both Wrangham's and Ghiglieri's models and, in addition, provided support for Alexander's (1974) contention that predation pressure is an ultimate cause of ape social structure. The model also outlined scenarios for the evolution of chimpanzee group._ extensibility (fusion-fission sociality) and the capacity for warfare among chimpanzees.The last objective was achieved by a discussion of the implications that the author's model had for phylogenetic models of stem-hominid social structure. In this discussion the author reviewed the following issues as they related to the phylogenetic reconstruction of hominid social structure: the role of phylogeny and/or ecology in the causation of social encountered when using a phylogenetic referential model for the personal biases that enter into phylogenetic econstructions; pitfalls reconstruction of early hominid social evolution; the significance of chimpanzee models of social structure.The importance of the preceding study lay in its ability to stimulate improved conceptual models of African hominoid social structure.<br>Department of Anthropology
45
楊可儀 and Ho-yee Yeung. "Study on the function and regulation of stanniocalcin in mouse neuroblastoma cells." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B31245043.
Full text
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Xie, Jeanne Yan. "The effect of development on spatial pattern separation in the hippocampus as quantified by the Homer1a immediate-early gene." Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Neuroscience, c2013, 2013. http://hdl.handle.net/10133/3414.
Full textAbstract:
This study sought to determine whether the DG, CA3, and CA1 regions contain
uniformly excitable populations and test the hypothesis that rapid addition of new, more
excitable, granule cells in prepubescence results in a low activation probability (P1) in the
DG. The immediate-early gene Homer1a was used as a neural activity marker to quantify
activation in juvenile (P28) and adult (~5 mo) rats during track running. The main finding
was that P1 in juveniles was substantially lower not only the DG, but also CA3 and CA1.
The P1 for a DG granule cell was close to 0 in juveniles, versus 0.58 in adults. The low P1
in juveniles indicates that sparse, but non-overlapping, subpopulations participate in
encoding events. Since sparse, orthogonal coding enhances a network’s ability to
decorrelate input patterns (Marr, 1971; McNaughton & Morris, 1987), the findings
suggest that juveniles likely possess greatly enhanced pattern separation ability.<br>ix, 51 leaves : ill. ; 29 cm
47
Kirkland, Scott, and University of Lethbridge Faculty of Arts and Science. "Modulation of recovery and compensation after stroke." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2007, 2007. http://hdl.handle.net/10133/387.
Full textAbstract:
Stress has been shown to exacerbate cell death and cognitive deficits after ischemic
injury in rodents, however, little is known of the effects of stress on motor recovery. The
objective of this present thesis is to examine the effects of chronic stress on skilled motor
recovery after devascularization lesion in rats. It was found that pre-lesion stress induced
the most behavioural impairments, while post-lesion stress exacerbated infarct volume.
The effects of chronic multiple stress on skilled motor recovery after lesion was also
examined. Chronic multiple stress did not modulate skilled motor recovery nor did it
have any influence on infarct volume. Additionally, stress had effect on edema after
devascularization lesion. The present thesis suggests that the time of exposure to chronic
stress in respect to the ischemic lesion, in addition to the type of stress, will differentially
affect recovery and compensation in rats.<br>xii, 122 leaves : ill. ; 29 cm.
48
Bolton, F. M. "Incorporating the 3Rs (Refinement, Replacement and Reduction of animals in research) into the preclinical assessment of snake venom toxicity and antivenom efficacy." Thesis, University of Liverpool, 2017. http://livrepository.liverpool.ac.uk/3007573/.
Full textAbstract:
Antivenom is the only effective treatment for snakebite and comprise immunoglobulins obtained from venom-immunised horses or sheep. Globally, more than 45 manufacturers make over 120 snake antivenoms; it is a regulatory requirement that the venom-neutralising efficacy of all antivenoms are assessed preclinically. The World Health Organisation (WHO) recommended preclinical tests of efficacy are the median lethal venom dose (LD50) and median effective antivenom dose (ED50) assays performed in mice. They result in substantial pain and suffering to the mice with death/survival as their metric. With NC3R-funding, we sought to apply the ‘Refine, Reduce and Replace’ principles of animal experimentation to these murine assays. Pain is a near-universal symptom of snake envenoming, and one of our objectives was to identify an effective analgesic that could be utilised without invalidating the assay results. The Mouse Grimace Scale and Activity scores were used to measure pain. We examined the effects of two opioid analgesics, buprenorphine and morphine, in a range of venom LD50 and ED50 assays. Both were effective at reducing pain scores, but death rates were higher in those which had received buprenorphine, hence morphine is preferable. We demonstrate that each venom exhibits a distinct set of lesions, the severity of which appears time and dose dependent, and that the observed murine pathological lesions show significant similarities to those reported in envenomed human victims. Applying the 3R principles, we have used pathological observations, in combination with ante mortem observations, to establish more humane end-points, consequently reducing the duration of LD50 and ED50 assays from 24 to 6 hours. In addition, we have implemented a ‘dose-staging’ element into experimental design in which one dose is given and the next dose(s) selected based on the results of the previous dose, reducing total mice required. To reduce the numbers of assays, and therefore mice, we have shown an excellent correlation between in vitro binding assays, cytotoxicity neutralisation assays and in vivo ED50 using antivenoms derived from the same pool of donor animals. Comparison of the results of in vitro binding assays between 35 different venom/antivenom combinations showed a poor correlation overall, but the correlation improved when each of five venoms were considered separately. The possibility of replacing the in vivo LD50 and ED50 tests, using a cell-based neutralisation assay was investigated using two cell lines from diverse tissues of origin, namely VERO epithelial-type cells and neural SH SY5Y. All venoms studied produced a cytopathic effect in both cell lines, with the VERO cells being more sensitive to viper venoms and SH SY5Y cells to the effects of elapid venoms, when both cell lines were grown in co-culture. However, variability of results made optimisation of a neutralisation assay inadequate for use as an alternative to in vivo tests.
49
Ithete, Ndapewa Laudika. "Investigation of small mammal-borne viruses with zoonotic potential in South Africa." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/85771.
Full textAbstract:
Thesis (PhD)-- Stellenbosch University, 2013.<br>ENGLISH ABSTRACT: The emergence and re-emergence of viral human pathogens from wildlife sources in the recent past has led to increased studies and surveillance of wildlife for potentially zoonotic agents in order to gain a better understanding of the pathogens, their sources as well as events that may lead to viral emergence. Of the >1407 known human pathogens, 13% are classified as emerging or re-emerging, and 58% as zoonotic; 37% of the (re-)emerging and 19% of the zoonotic pathogens are RNA viruses, accounting for the majority of recently emerged infectious diseases with a zoonotic origin, such as HIV, Ebola, Hendra, Nipah, Influenza and SARS.
This study focusses on potentially zoonotic viruses hosted by rodents (Muridae family), shrews (order previously known as Insectivora/Soricomorpha, now reclassified as Eulipotyphla) and bats (order Chiroptera). Rodents and bats represent the largest (~40%) and second largest (~25%) mammalian orders and both occur on every continent except Antarctica. Together, the three mammalian orders investigated represent the most relevant potential sources of new zoonoses.
In this study I investigated the occurrence of astroviruses, arenaviruses, coronaviruses and hantaviruses in South African small mammal species belonging to the orders mentioned above. These viruses have either been implicated in recent emerging zoonotic events or are considered to have the potential to cause cross-species transmissions resulting in a zoonotic event. In the first part of the study specimens collected from various bat, rodent and shrew species were screened for viral sequences by broadly reactive PCRs; positive samples were characterised by sequencing and sequence analysis. A separate part of the study focussed on hantavirus disease in humans: a seroprevalance survey was conducted to determine the presence of hantavirus antibodies in the local population. Additionally, acutely ill patients with potential hantavirus disease were tested in an attempt to identify possible acute infections and define clinical hantavirus disease in South Africa.
Screening of rodent and shrew specimens resulted in the identification of eight novel arenavirus sequences. Seven of the sequences are related to Merino Walk virus, a recently identified South African arenavirus, and the eighth sequence represents a novel lineage of Old World arenaviruses.
Screening of bat specimens resulted in the identification of highly diverse novel astrovirus and coronavirus sequences in various South African bat species, including the identification of a viral sequence closely related to the recently emerged Middle East Respiratory Syndrome coronavirus.
While the study did not identify hantavirus infections in any of the acutely ill patients, it found seroprevalences similar to those observed in Europe and West Africa.
The results obtained highlight the importance of small mammals in the emergence of potential zoonoses and further reinforce the importance of viral surveillance of relevant wildlife species. Further in-depth studies of naturally infected reservoir host populations are required in order to gain a better understanding of virus-host dynamics and the events that lead to virus emergence.<br>German Research Foundation (DFG) (project number: KR1293/9-1/13-1)<br>The Polio Research Foundation and the NHLS Research<br>Harry Crossley Foundation, the Polio Research Foundation and Stellenbosch University for granting scholarships and bursaries for PhD.
50
Petersson, Kerstin, and Veronica Gyllenbrodd. "Att delta i hundbaserad omvårdnad : en litteraturöversikt om patienters upplevelser och erfarenheter." Thesis, Högskolan Kristianstad, Sektionen för hälsa och samhälle, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hkr:diva-17686.
Full textAbstract:
Bakgrund: Användandet av djur inom vård- och omsorgsverksamheter har visat sig ha en positiv inverkan på bland annat patienters blodtryck, hjärtfrekvens och depression, och hundar har visat sig vara mer effektiva vid omvårdnadsbehandling jämfört med andra djur eftersom hundarna har det mest utvecklade kommunikationssystemet av våra sällskapsdjur. Följaktligen finns ett kunskapsbehov om patienters erfarenheter och upplevelser av hundbaserad omvårdnad. Syfte: Syftet med studien var att beskriva patienters upplevelser och erfarenheter av hundbaserad omvårdnad inom vård- och omsorgsverksamheter. Metod: En litteraturöversikt som baserades på sex vetenskapliga kvalitativa artiklar genomfördes. Artikelgranskning skedde utifrån Högskolan Kristianstads granskningsmall och analysarbetet följde Fribergs rekommendationer. Resultat: Det framkom tre huvudkategorier, Hundens betydelse i omvårdnaden, Hundens betydelse för välmåendet och Hundens betydelse för ett meningsfullt dagligt liv. Patienterna kände bland annat glädje, trygghet, meningsfullhet, ökad livskvalité och bekräftelse. Den hundbaserade omvårdnaden ökade också den sociala samvaron och bidrog dessutom till ökad självsäkerhet hos patienterna. Slutsats: Samtliga patienter oavsett ålder, kön, verksamhetsområde och diagnos erfor hundbaserad omvårdnad som positiv. Liknande resultat framkom även vid alternativa behandlingsmetoder, således behövs mer forskning om hundbaserad omvårdnad då det med säkerhet inte går att fastställa vad det är som bidrar till patienternas upplevelser och erfarenheter.