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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
271

Cellular regulation of molecular chaperones and identification of pathogenic pathways in polyglutamine disease. / CUHK electronic theses & dissertations collection

January 2006 (has links)
Polyglutamine disease is a class of neurodegenerative diseases, which is manifested by the atrophy of nervous system that results in dementia and/or motor dysfunction. The major pathological characteristics include progressive loss of neuronal cells as well as the appearance of insoluble nuclear inclusions in degenerating neuronal cells. Polyglutamine disease is caused by CAG triplet expansion in the genome. When translated, such expansion leads to the formation of expanded polyglutamine domain within the respective disease proteins and promotes abnormal protein conformational changes. Owing to their misfolded nature, the expanded polyglutamine proteins form insoluble nuclear inclusions. These insoluble nuclear inclusions are heterogeneous in nature, in which polyglutamine protein and molecular chaperones are the recruited components. All eukaryotic cells express molecular chaperones which function to mediate the proper folding of proteins. The recruitment of molecular chaperones into nuclear inclusions that contain misfolded triplet-expanded proteins strongly suggests the involvement of molecular chaperones in polyglutamine disease progression. It has been shown that over-expression of molecular chaperones in polyglutamine disease models can lead to a suppression of polyglutamine toxicity and a concomitant increase in the solubility of disease proteins, i.e. the solubility of polyglutamine disease protein is related to its toxicity. Intrigued by these observations, I aimed at elucidating the mechanism of polyglutamine disease pathogenesis by first studying the cellular regulation of endogenous chaperone expression in neurodegeneration in a transgenic Drosophila model of polyglutamine disease. A biphasic regulation of Hsp70 expression was observed, which the regulation was at the transcription level. Moreover, over-expression of Hsp70 could alter the endogenous Hsp70 protein and mRNA level of polyglutamine disease fly model. The study may help the understanding of how the chaperone expression is regulated under the effects of polyglutamine expression and thus to find out the mechanism of pathogenesis. In addition, cellular proteins that change in solubility other than disease protein will also be identified. Small heat shock proteins, glutathione S transferase and alpha 4 proteasome subunit, etc., showed change in solubility or expression by 2D gel electrophoresis analysis. Identifying the proteins that change in solubility or expression may help the finding of the interplay of proteins and thus the pathways involve in the mechanism of polyglutamine disease pathogenesis. Understanding pathogenic pathways can give ideas on how polyglutamine lead to the disease, up- or down-regulation of those protein interplays may provide direction and therapeutic candidates to suppress polyglutamine disease. / Huen Ngar Yee. / "September 2006." / Advisers: Ho Yin Chan; Siu Kai Kong. / Source: Dissertation Abstracts International, Volume: 68-03, Section: B, page: 1465. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (p. 134-146). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
272

CRÍTICA ROUSSEAUNIANA DA IMITAÇÃO TEATRAL: da recusa do teatro de classe francês ao consentimento da festa / ROUSSEAUNIAN CRITICISM OF THEATRICAL IMITATION: the refusal of theater French class to the party's consent

TAVARES, Márcio Júnior Montelo 26 May 2017 (has links)
Submitted by Maria Aparecida (cidazen@gmail.com) on 2017-07-25T12:00:41Z No. of bitstreams: 1 Márcio Júnior.pdf: 700191 bytes, checksum: b80202af09892b899af3e4bd760c67dd (MD5) / Made available in DSpace on 2017-07-25T12:00:41Z (GMT). No. of bitstreams: 1 Márcio Júnior.pdf: 700191 bytes, checksum: b80202af09892b899af3e4bd760c67dd (MD5) Previous issue date: 2017-05-26 / In the present bibliographical research, the theater is analyzed, under a critical perspective, as an imitation of the social representation in the writings of JeanJacques Rousseau, taking as a parameter the criticism elaborated by the philosopher genebrino on the French theater, especially in what concerns The comedy of customs advocated by thinkers such as Voltaire and D'Alembert, as well as his negative response to the question about the contribution of the sciences and the arts to the moral improvement of man, presented in his First Discourse. In this panorama, Rousseau disproves most of the philosophers of his time, showing that art, instead of elevating man to a higher moral level, corrupts it by making it vile and attached to frivolities and luxuries unnecessary to a society Virtuous Indeed, unlike ordinary Enlightenment thought, the Geneva philosopher did not assert that this society and that historical moment in which he was inserted represented the pinnacle of moral progress in the history of human civilization, but rather preached that the man had entered a dangerous Process of moral degeneration, of narcissism, from which the other is taken as a mere projection of itself. In this way, we are dealing with the French theater considerations of some Enlightenment philosophers, as well as the answer given by Rousseau to D'Alembert in the famous missive on the Geneva entry in Diderot's Encyclopaedia. It is concluded that, while recognizing the importance of the sciences and the arts for humanity, Rousseau viewed such dimensions of knowledge as harmful insofar as they served distorted purposes, especially when used as a form of distinction between men. The theater, conceived in this perspective, had the function of being simple distraction for the masses, being mere caricature of the daily life. / Na presente pesquisa de cunho bibliográfico, analisa-se o teatro, sob uma ótica crítica, como imitação da representação social nos escritos de Jean-Jacques Rousseau, tomando como parâmetro a crítica elaborada pelo filósofo genebrino sobre o teatro francês, em especial no que tange a comédia de costumes defendida por pensadores como Voltaire e D‟Alembert, bem como sua resposta negativa à questão acerca da contribuição das ciências e das artes para o aprimoramento moral do homem, apresentada no seu Primeiro Discurso. Neste panorama, Rousseau destoa de grande parte dos filósofos de seu tempo, mostrando que a arte, em vez de elevar o homem a um patamar moral superior, acaba corrompendo-o, tornando-o vil e apegado a frivolidades e luxos desnecessários a uma sociedade virtuosa. Aliás, diferente do pensamento iluminista corrente, o filósofo genebrino não asseverou que aquela sociedade e aquele momento histórico nos quais ele estava inserido representavam o auge do progresso moral da história da civilização humana, mas, antes, preconizou que o homem tinha entrado em um perigoso processo de degeneração moral, de narcisismo, a partir do qual o outro é tomado como mera projeção de si mesmo. Aborda-se, assim, as considerações sobre o teatro francês tecidas por alguns filósofos iluministas, bem como a resposta dada por Rousseau a D‟Alembert na célebre missiva a respeito do verbete Genebra contido na Enciclopédia de Diderot. Conclui-se que, mesmo reconhecendo a importância das ciências e das artes para a humanidade, Rousseau via tais dimensões do conhecimento como danosas na medida em que serviam a propósitos distorcidos, em especial quando utilizadas como forma de distinção entre os homens. O teatro, concebido nesta perspectiva, tinha como função ser simples distração para as massas, sendo mera caricatura da vida cotidiana.
273

Influence of Mechanical Choices on Development and Persistence of Osteoarthritis: How Alexander Technique Can Promote Prevention and Management

Lowry, Rachelle E 01 May 2016 (has links)
Is osteoarthritis a fate unconditionally vested in genetic makeup, or are joints aggravated into inflammation by the way they are treated? Humans are a complicated conglomeration of experiences, decisions, and inheritance. Osteoarthritis, likewise, has evaded simplicity in any explanation of its causation, so it necessitates a multi-dimensional perspective. This research considers the relevance of Alexander Technique in filling a void in which treatment and management of osteoarthritis is not equally equipped to answer this multi-dimensional causation. Alexander Technique is classified as a movement therapy, but this does not quite encompass the mindset of it—that it is indeed largely a mindset about movement. More concisely, Alexander Technique emphasizes self-awareness about how a person uses his or her body to perform daily tasks. It is physical minimalism, and involves continual recognition of muscle tension along with the ability to let go of any tension that is burdensome and unnecessary. This technique has diminished pain and increased the ease of movement for those who have experienced it, even people with osteoarthritis. To build the argument that osteoarthritis can be hindered through a heightened consideration of how joints are treated, the initial component of this research investigated the vast amount of information already gleaned about the pathogenesis of this disease. The fields of physiology, genetics, immunology, and clinical practice already have much to share, and this knowledge has been combined with studies about the benefits and goals of Alexander Technique to discover the common ground of osteoarthritis treatment. The experimental component assesses the association of Alexander Technique to the minimization of pain from osteoarthritis. An online survey asks osteoarthritis cohorts about the history of their disease, the effect it has had on their pain levels and activities of daily living, and about the efficacy of their management strategies. Because each participant will be asked if he or she has received Alexander Technique lessons, the survey can be used to analyze each respondent’s experience of osteoarthritis with respect to that. It was found that participants who had received Alexander Technique lessons reported an average of one more pain-free day per week, and experienced diminished pain levels for daily physical activities such as walking. Management strategies also indicated the benefit of Alexander Technique; those who had taken lessons less frequently used pain and anti-inflammatory medications and were able to be more physically active than the unexposed group. No statistical significance was achieved from the data, largely owing to small sample size (Alexander Technique, n=12, no Alexander Technique, n=25). This study is a step in the direction of better osteoarthritis management, promoting prevention-minded awareness of joint use and providing preliminary fuel for more extensive research.
274

Molecular investigations of age-related macular degeneration

Whitmore, Steven Scott 01 May 2015 (has links)
An estimated 170.38 million elderly adults suffer from some stage of age-related macular degeneration (AMD) worldwide, a vision defect that damages the macula, the central region of the retina required for sharp vision, such as reading, driving, and recognizing faces. Genetic factors strongly modify one's risk for developing AMD, and most of these genetic changes are found in genes of the alternative complement cascade, a component of the immune system. The lack of effective AMD prevention calls for the identification of druggable molecules and pathways. In my research, I use microarrays and RNA sequencing to investigate the events occurring in early AMD, the reasons for macular susceptibility to AMD, and the events triggering aberrant blood vessel growth in late AMD. First, I found that genes associated with endothelial cells tend to be expressed at lower levels in human donors eyes affected by early AMD than in control eyes, concordant with previous studies indicating loss of choriocapillaris in early AMD. Second, I found that molecular signals across regions of the retina, retinal pigment epithelium, and choroid generally mirror the distribution of cell types in these regions. Third, I found that damage to cultured primate chorioretinal endothelial cells by the end product of complement activation, membrane attack complex, produces an environment conducive to choroidal neovascularization, a symptom of late-stage AMD. I propose a model that bridges genetic variants in the complement cascade genes with blood vessel loss in early AMD and the pathological growth of blood vessels in late AMD.
275

Detection, interpretation, and functional consequences of genomic copy number variation in human disease

Meyer, Kacie Jo 01 May 2011 (has links)
In recent years, microarray technology has revealed the widespread presence of submicroscopic deletions and duplications throughout the human genome termed copy number variants (CNVs). CNVs have a profound effect on gene expression and are an important source of normal genetic variation. In addition, a small proportion of CNVs contribute to genetically simple and complex disease. This thesis focuses on the identification of pathogenic CNVs contributing to the etiology of diseases with "missing heritability" using a well-planned study design individually tailored to each disease cohort to optimize CNV detection and interpretation. We performed a genome-wide analysis for CNVs in five disease cohorts with genetic etiology: autism, age-related macular degeneration (AMD), glaucoma, clubfoot, and Bardet-Biedl syndrome (BBS). Our results indicate that CNVs likely account for a proportion of cases for each disease cohort reported in this thesis. Approximately 20% of our cohort of individuals with autism from trio pedigrees harbors a CNV known to confer risk to develop autism and we identified other novel and rare variants that may play a role in autism pathogenesis. We also characterized a duplication of 2p25.3 identified in two male half-siblings with autism and determined that their mother was somatic mosaic for the duplication. Our work provides evidence that this novel CNV disrupting the genes PXDN and MYT1L are the autism-causing mutation in this pedigree. A comparative cases experimental design was used in the study of AMD and glaucoma. While no common "risk CNVs" were identified for either eye disorder, we did identify several rare overlapping CNVs disrupting genes known to play a role in the eye that may confer risk to disease in a small proportion of individuals. In a fourth genetically complex disease, clubfoot, we identified a duplication of 17q23.2 disrupting the genes TBX4, NACA2, and BRIP1 that segregates with the autosomal dominant clubfoot phenotype in a large pedigree with 16 affected individuals. In addition, the duplication is within the linkage interval identified for this family. We also applied microarray technology to analyze the genomes of individuals with BBS, an autosomal recessive disorder, for the presence of CNVs in known BBS genes as well as CNVs that elucidate novel candidate genes for BBS. From 34 BBS patients with an unidentified mutation, we observed one CNV, a heterozygous deletion of BBS10, unmasking a BBS10 frameshift mutation. A promising BBS candidate gene also emerged from our studies, implicated by an intragenic deletion of the gene MARK3 predicted to result in a frameshift and premature truncation of the protein. Functional studies utilizing antisense morpholino gene knockdown in the zebrafish provide additional evidence that MARK3 is a BBS gene as knockdown of zebrafish mark3 results in a Kupffer's Vesicle defect and a melanosome transport delay, two cardinal BBS phenotypes in the zebrafish. In addition to identifying CNVs involved in disease, the work outlined in this thesis provides valuable insight into the study design and interpretation of a genome-wide analysis of CNV. This includes the appropriate use of controls and publicly available control databases, methods for enriching for CNVs in a patient cohort to maximize efficiency and discovery, and the importance of analyzing all patient cohorts with heritable disease for the presence of CNVs disrupting known disease genes and CNVs that implicate novel genetic candidates. As the reliability and resolution of CNV detection continue to improve, allowing detection of > 1,000 CNVs in each individual genome, it becomes more important than ever to have a well-defined study design for both the detection and interpretation of CNVs.
276

Whole exome sequencing in identifying genetic factors in musculoskeletal diseases

Skarp, S. (Sini) 19 November 2019 (has links)
Abstract Musculoskeletal diseases, such as osteoarthritis (OA), lumbar disc degeneration (LDD) and osteoporosis (OP), are common complex disorders affected by both environmental and genetic factors. OA and LDD are degenerative diseases affecting joints and spine and Modic changes (MC) are a specific phenotype of LDD. OP is a disorder causing bone fragility. There are families with a history of early onset cartilage degradation, disc disorders and bone fragility as well as rare, more severe disorders with these traits as part of the phenotype. The aim of this study was to identify predisposing genetic factors in Finnish families with three different musculoskeletal phenotypes and to investigate the use of whole exome sequencing (WES) as a tool. Six families were studied here, three diagnosed with hip and knee OA, two with MC and one with primary OP. Using WES together with in silico and in vitro analyses we identified new candidate genes. In the two OA families we identified family specific variants, c.-127G>T in the 5’UTR of FIP1L1 and p.Arg210Gly in OLIG3. We observed expression of these genes in human bone and cartilage. Both FIP1L1 and OLIG3 participate in the regulation of transcription. Family specific variants were also found in both families with MC: p.Gln1611fs in HSPG2 and p.Glu553Lys in MAML1. HSPG2 encodes for an important structural protein in the disc and MAML1 is a transcription factor. The family with primary OP had previously been reported to carry a heterozygous COL1A2 deletion leading to nonsense-mediated mRNA decay. In the WES we identified an additional change that may contribute to the phenotype: p.Arg428* in ZNF528. We showed experimentally that the variant leads to expression of a truncated form of ZNF528 in the nucleus. ZNF528 binding sites are located near genes associated with bone phenotypes. We identified twelve potential target genes for ZNF528 that were differentially expressed in patients’ cells compared to controls. Altogether, we identified five new candidate genes for the studied phenotypes demonstrating that WES can be used as a tool in studying complex musculoskeletal phenotypes in families. One of the identified candidate genes, HSPG2, encodes a structural protein, whereas, OLIG3, FIP1L1, MAML1 and ZNF528, participate in the regulation of transcription supporting the importance of regulatory mechanisms in the pathogenesis of musculoskeletal diseases. / Tiivistelmä Tuki- ja liikuntaelinsairaudet, kuten nivelrikko, välilevyrappeuma ja osteoporoosi, ovat yleisiä, monitekijäisiä sairauksia. Nivelrikko ja välilevynrappeuma ovat eteneviä nivelten ja selkärangan sairauksia. Modic muutokset ovat välilevyn ja nikaman välisten päätelevyjen muutoksia. Osteoporoosi on luuta haurastuttava sairaus. Varhaisessa iässä ilmenevää ruston haurastumista, välilevyn sairauksia tai luun haurautta tavataan myös suvuittain esiintyvinä sairauksina tai vakavien harvinaisten sairauksien oireina. Tutkimuksen tarkoitus oli tunnistaa altistavia geneettisiä tekijöitä kolmelle tuki- ja liikuntaelimistön sairaudelle suomalaisissa perheissä käyttäen eksomisekvensointi-menetelmää. Aineisto koostui kuudesta perheestä: kolmessa oli diagnosoitu lonkan ja polven nivelrikko, kahdessa selän välilevyjen Modic muutoksia ja yhdessä primaarinen vaikea selän osteoporoosi. Tunnistimme uusia ehdokasgeenejä käyttäen eksomisekvensointi-menetelmää sekä in silico ja in vitro analyysejä. Kahdessa nivelrikkoperheessä tunnistimme perhekohtaiset variantit kahdessa geenissä: c.-127G>T variantin FIP1L1 geenin säätelyalueella ja p.Arg210Gly variantin OLIG3 geenissä. Osoitimme, että nämä traskription säätelyyn osallistuvat geenit ilmenevät ihmisen luu- ja rustokudoksessa. Perhekohtaiset variantit havaittiin myös perheissä, joilla oli todettu Modic muutoksia: p.Gln1611fs HSPG2 -geenissä ja p.Glu553Lys MAML1 -geenissä. HSPG2 koodaa välilevylle tärkeää rakenneproteiinia ja MAML1 on transkriptiota säätelevä tekijä. Primaarista osteoporoosia sairastavalla perheellä oli aiemmin havaittu heterotsygootti, geenituotteen hajottamiseen johtava deleetio, COL1A2 -geenissä. Eksomisekvensoinnlla havaitsimme mahdollisesti taudin ilmiasuun lisäksi vaikuttavan muutoksen ZNF528 -geenissä. Osoitimme kokeellisesti, että havaittu variantti johtaa lyhentyneen proteiinin tuottoon solussa. ZNF528 on transkriptiotekijä, jolle tunnistimme kaksitoista mahdollista kohdegeeniä ja havaitsimme että niiden tuotto oli muuttunut potilaiden soluissa kontrollisoluihin verrattuna. Tunnistimme viisi uutta ehdokasgeeniä kolmessa eri sairaudessa eksomisekvensointi-menetelmän avulla. Yksi tunnistetuista geeneistä, HSPG2, koodaa rakenneproteiinia, ja muut osallistuvat transkription säätelyyn. Tämä tukee käsitystä säätelytekijöiden tärkeydestä TULE sairauksien synnyssä.
277

Computational Modeling to Study Disease Development: Applications to Breast Cancer and an in vitro Model of Macular Degeneration

Bani Baker, Qanita 01 May 2015 (has links)
There have been several techniques developed in recent years to develop computer models of a variety of disease behaviors. Agent-based modeling is a discrete-based modeling approach used agents to represent individual cells that mechanically interact and secrete, consume or react to soluble products. It has become a powerful modeling approach, widely used by computational researchers. In this research, we utilized agent-based modeling to study and explore disease development, particularly in two applications, breast cancer and bioengineering experiments. We further proposed an error-minimization search approach and used it to estimate cellular parameters from multicellular in vitro data. In this dissertation, in the first study, we developed a 2D agent-based model that attempted to emulate the in vivo structure of breast cancer. The model was applied to describe the progression from DCIS into DCI. This model confirms that the interaction between tumor cells and the surrounding stroma in the duct plays a critical role in tumor growth and metastasis. This interaction depends on many mechanical and chemical factors that work with each other to produce tumor invasion of the surrounding tissue. In the second study, an in silico model was developed and applied to understanding the underlying mechanism of vascular-endothelial growth factor (VEGF) auto-regulation in REP and emulate the in vitro experiments as part of bioengineering research. This model may provide a system with robust predictive modeling and visualization that could enable discovery of the molecular mechanisms involved in age-related macular degeneration (AMD) progression and provide routers to the development of effective treatments. In the third and final study, a searching approach was applied to estimate cellular parameters from spatiotemporal data produced from bioengineered multicellular in vitro experiments. We applied a search method to an integrated cellular and multicellular model of retinal pigment epithelial cells to estimate the auto-regulation parameters of VEGF.
278

Role of SARM1 in Chronic Immune-Mediated Central Nervous System Inflammation

Viar, Kenneth E, II 01 January 2019 (has links)
SARM1 is an injury-induced nicotinamide adenine dinucleotide nucleosidase (NADase) that was previously shown to promote axonal degeneration in response to traumatic, toxic, and excitotoxic stressors. This raises the question of whether a SARM1-dependent program of axonal degeneration is central to a common pathway contributing to disease burden in neurological disorders. The degree to and mechanism by which SARM1 inactivation decreases the pathophysiology of such disorders is of interest to establish the rationale to pursue SARM1 as a therapeutic target. In this study, we compare the course and pathology of experimental autoimmune encephalomyelitis (EAE) in Sarm1-knockout (KO) mice and wild-type littermates to test the contribution of SARM1-dependent axonal degeneration specifically in the context of chronic, immune-mediated central nervous system (CNS) inflammation. The question of whether SARM1 loss in Sarm1-KO mice would inhibit, promote, or have a negligible impact on EAE-induced axonal degeneration and more broadly CNS inflammation was explored using a variety of analyses: quantification of clinical score in a chronic EAE model, CNS immune infiltrate profile, axon initial segment morphology in layer V cortical neurons, axonal transport disruption and transection in the lumbar spinal cord. Additionally, we have proposed a method for detecting SARM1 activation in situusing a novel SARM1-mCitrine bimolecular fluorescence complementation (BiFC) technique. Successful implementation of such a molecular tool would allow for a detailed, mechanistic approach to enhance our understanding of upstream intracellular signals that trigger SARM1 activation.
279

Association Between Age-Related Macular Degeneration and Sleep-Disordered Breathing

Nau, Jeffrey A. 01 January 2017 (has links)
Age-related macular degeneration (AMD) is a chronic, irreversible disease that robs individuals of vision, quality of life, and independence. It is the leading cause of blindness in industrialized countries. Sleep-disordered breathing (SDB) is a condition characterized by repeated episodes of apnea and/or hypopnea, insomnia, short sleep duration, and/or sleep disturbances (snoring, gasping, etc.). Because SDB has been shown to cause chronic hypoxia resulting in oxidative stress on the retina, it has been proposed that SDB may be associated with AMD. Based on the life course theory of chronic disease, this quantitative, cross-sectional study used data from the 2005-2008 National Health and Nutrition Examination Survey to study whether there was an association between SDB and AMD, including neovascular AMD and geographic atrophy in adults 40 years and older. Descriptive statistics and logistic regression analyses were used. The results suggest that AMD is associated with diagnosed sleep disorders, including sleep apnea and insomnia, as well as sleep apnea symptoms of gasping snoring, snorting, and stopping breathing. The findings of this study highlight the importance of diagnostic screening and therapeutic intervention to treat SDB. Early diagnosis and therapy for SDB could address not only the comorbidities associated with SDB, but could also prevent or slow the progression of AMD. In turn, this would yield lower rates of vision loss, reduced comorbidities associated with vision loss, and reduced impact of AMD on the health care system and social and financial costs to society.
280

An Assessment of Cognitive and Sensorimotor Deficits Associated with APPsw and P301L Mouse Models of Alzheimer's Disease

Garcia, Marcos F 31 March 2003 (has links)
Behavioral characterization of animal models for Alzheimer's Disease is critical for the development of potential therapeutics and treatments against the disease. While there are several known animal models of AD, three current models--APPsw, P301L, and APPsw+P301L--have not been well characterized, if at all. This study, therefore, aimed to perform a full behavioral characterization of these three models in order to better understand the impairments associated with each one. Between 5 and 8.5 months of age, animals were behaviorally tested in a variety of sensorimotor, anxiety, and cognitive tasks. The number of tau+ neurons in the forebrains of P301L mice was then compared to their behavioral performance. Results of this study indicate that retinal degeneration (rd) seriously impairs the performance of mice in behavioral tasks. Animals that carry the homozygous allele of this mutation must, therefore, be eliminated from any such study requiring visual acuity. After this elimination, my findings indicate that APP mice are impaired in several cognitive tasks (including platform recognition, Morris maze, Y-maze, and radial-arm water maze) at a young early age (5 to 8.5 months of age). These mice have fairly normal sensorimotor function, showing significant impairment only in balance beam performance starting at 5 months. Although P301L mutant Tau mice, as a group, did not have significant impairments in any sensorimotor or cognitive task, correlation analysis revealed that higher numbers of tau+ neurons in cortex and hippocampus were associated with poorer cognitive performance. Finally, discriminant function analysis (DFA) appears able to accurately discriminate between the three transgenic groups of mice using only an 8-measure data set. In conclusion, this study provides the first comprehensive, multiple task behavioral assessment of the APPsw and P301L animal models of AD, indicating that APPsw mice are cognitively impaired at an early age while P301L mice are largely unimpaired through 8.5 months. Nonetheless, correlational analysis implicates the formation of neurofibrillary tangles in the onset of cognitive impairments. Finally, my findings recommend the continued use of DFA to determine if groups of animals, based on different transgenicity or therapeutic treatment, could be discriminated between from their behavior alone.

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