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The Role Of Histone Methylation In The Medial Temporal Lobe During Long-Term Memory Formation, Swati Gupta

All ETDs from UAB

Several studies have established the importance of epigenetic regulation of gene transcription in the brain during memory consolidation. Epigenetic mechanisms involve modifying the DNA or the associated histone proteins to determine the transcriptional outcome of a gene. The work encompassed in this dissertation serves as an initial investigation for the role of histone lysine methylation mechanisms in regulating gene activation and suppression in the medial temporal lobe that includes entorhinal cortex (EC), hippocampus, and amygdala during memory consolidation. To this end, we found that di-methylation of histone H3 at lysine 9 (H3K9me2) which promotes gene suppression was specific to associative …

The Role Of Vpr-1 Msp Signaling In C. Elegans, Sung Min Han

All ETDs from UAB

In C. elegans, the major sperm protein (MSP) is the most abundant protein in sperm and functions as an intracellular cytoskeleton protein and a secreted extracellular signal that induces oocyte maturation and sheath contraction. Evolutionarily, MSP domain-containing proteins originate from the VAPs (VAMP/synaptobrevin-associated proteins), which comprise a highly conserved protein family with an MSP domain at the N-terminus and a transmembrane domain at the C-terminus. I have been studying the signaling role of VAP MSP domains using the C. elegans model system. In collaboration with Hugo Bellen's lab at Baylor College of Medicine, we have shown that C. elegans, Drosophila, …

Mitochondrial Morphology And Function In Neuronal Cells Under Stress, Lonnie Schneider

All ETDs from UAB

Neurodegenerative disease encompasses a wide range of conditions and pathologies that can manifest at any age depending on the etiology. A major factor in both early onset and age-related neurodegeneration is mitochondrial dysfunction. To investigate how mitochondrial bioenergetics is affected by cellular stress, we used an in vitro culture system to examine mitochondrial function in response to oxidative stress. We also studied an in vivo model of neuronal ceroid lipofuscinosis to determine the impact of deficient autophagy-lysosomal activity on mitochondrial morphology, composition and function. In vitro we found that retinoic acid-induced differentiation of dopaminergic neuroblastoma SH-SY5Y cells exhibited increased mitochondrial …

Innate Immune Mechanisms Against The Atypical Fungal Pathogen Pneumocystis Murina, Michael Paul Nelson

All ETDs from UAB

Pneumonia caused by the fungal pathogen Pneumocystis continues to be the leading cause of morbidity and mortality in AIDS patients. In addition, there are a number of other non-HIV-associated diseases that render an individual susceptible to Pneumocystis infection, including chronic obstructive pulmonary disease. Innate immune mechanisms are important for controlling Pneumocystis lung infection. As alveolar macrophages serve the front lines of lung host defense, our goal was to elucidate their responses during lung Pneumocystis infection. Here, we established a role for Src family kinases in the lung immune response to Pneumocystis, which uncovered a role for alternatively activated alveolar macrophages. …

Thomas Jefferson University, Department Of Pathology, Anatomy And Cell Biology, Oral Administration Of Apigenin Inhibits Metastasis Through Akt/P70s6k1/Mmp-9 Pathway In Orthotopic Ovarian Tumor Model., Jun He, Qing Xu, Min Wang, Chongyong Li, Xu Qian, Zhumei Shi, Ling-Zhi Liu, Bing-Hua Jiang

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Apigenin, a flavonoid commonly present in the daily diet, is known for its potential anti-tumor properties. However, the effect of apigenin via oral administration on tumor growth and metastasis remains unknown. In this study we developed an orthotopic ovarian tumor model in nude mice to test the effect of apigenin oral administration, and showed that apigenin inhibited the micrometastasis of cancer cells in the animal tumor model. To understand the mechanism of apigenin in inhibiting metastasis, we found that apigenin greatly inhibited MMP-9 expression and p-AKT and p-p70S6K1 levels in the tumor tissues compared to the control group. We further …

Loss Of Axonal Mitochondria Promotes Tau-Mediated Neurodegeneration And Alzheimer's Disease-Related Tau Phosphorylation Via Par-1., Kanae Iijima-Ando, Michiko Sekiya, Akiko Maruko-Otake, Yosuke Ohtake, Emiko Suzuki, Bingwei Lu, Koichi M Iijima

Farber Institute for Neuroscience Faculty Papers

Abnormal phosphorylation and toxicity of a microtubule-associated protein tau are involved in the pathogenesis of Alzheimer's disease (AD); however, what pathological conditions trigger tau abnormality in AD is not fully understood. A reduction in the number of mitochondria in the axon has been implicated in AD. In this study, we investigated whether and how loss of axonal mitochondria promotes tau phosphorylation and toxicity in vivo. Using transgenic Drosophila expressing human tau, we found that RNAi-mediated knockdown of milton or Miro, an adaptor protein essential for axonal transport of mitochondria, enhanced human tau-induced neurodegeneration. Tau phosphorylation at an AD-related site Ser262 …

Glucose Decouples Intracellular Ca2+ Activity From Glucagon Secretion In Mouse Pancreatic Islet Alpha-Cells., Sylvain J Le Marchand, David W Piston

Farber Institute for Neuroscience Faculty Papers

The mechanisms of glucagon secretion and its suppression by glucose are presently unknown. This study investigates the relationship between intracellular calcium levels ([Ca(2+)](i)) and hormone secretion under low and high glucose conditions. We examined the effects of modulating ion channel activities on [Ca(2+)](i) and hormone secretion from ex vivo mouse pancreatic islets. Glucagon-secreting α-cells were unambiguously identified by cell specific expression of fluorescent proteins. We found that activation of L-type voltage-gated calcium channels is critical for α-cell calcium oscillations and glucagon secretion at low glucose levels. Calcium channel activation depends on K(ATP) channel activity but not on tetrodotoxin-sensitive Na(+) channels. …

Testosterone Treatment Fails To Accelerate Disease In A Transgenic Mouse Model Of Spinal And Bulbar Muscular Atrophy., Erica S Chevalier-Larsen, Diane E Merry

Department of Biochemistry and Molecular Biology Faculty Papers

Evidence from multiple animal models demonstrates that testosterone plays a crucial role in the progression of symptoms in spinal and bulbar muscular atrophy (SBMA), a condition that results in neurodegeneration and muscle atrophy in affected men. Mice bearing a transgene encoding a human androgen receptor (AR) that contains a stretch of 112 glutamines (expanded polyglutamine tract; AR112Q mice) reproduce several aspects of the human disease. We treated transgenic male AR112Q mice with testosterone for 6 months. Surprisingly, testosterone treatment of AR112Q males did not exacerbate the disease. Although transgenic AR112Q males exhibited functional deficits when compared with non-transgenics, long-term testosterone …

Mitochondrial Lysyl-Trna Synthetase Independent Import Of Trna Lysine Into Yeast Mitochondria., Naresh Babu V Sepuri, Madhavi Gorla, Michael P King

Department of Biochemistry and Molecular Biology Faculty Papers

Aminoacyl tRNA synthetases play a central role in protein synthesis by charging tRNAs with amino acids. Yeast mitochondrial lysyl tRNA synthetase (Msk1), in addition to the aminoacylation of mitochondrial tRNA, also functions as a chaperone to facilitate the import of cytosolic lysyl tRNA. In this report, we show that human mitochondrial Kars (lysyl tRNA synthetase) can complement the growth defect associated with the loss of yeast Msk1 and can additionally facilitate the in vitro import of tRNA into mitochondria. Surprisingly, the import of lysyl tRNA can occur independent of Msk1 in vivo. This suggests that an alternative mechanism is present …

Evaluation Of Protection Induced By Dna Vaccine Candidate Against Leishmania Mexicana In Balb/C Mice Model, Rosina Rodarte

Open Access Theses & Dissertations

Background and Significance. The leishmaniases are a diverse group of diseases with four major clinical manifestations: cutaneous, mucocutaneous, visceral, and diffuse. Approximately 21 Leishmania species and 30 sandfly vectors have been implicated in human leishmaniasis. Leishmaniasis is endemic in 88 countries, 72 are developing countries. Currently, 350 million people live in leishmaniasis-endemic areas around the world. The true incidence of the disease is not known. However, the estimated incidence for visceral leishmaniasis is 500,000 cases per year, and for cutaneous and mucocutaneous leishmaniasis 1.5-2 million cases per year. Visceral leishmaniasis causes 70,000 deaths each year. In the Americas region, …

Role Of Myosin Light Chain Kinase In Binge Ethanol And Burn Injury-Induced Intestinal Barrier Dysfunction, Anita Zahs

Dissertations

Ethanol is a common factor in traumatic injury, including burn injury. Previous studies from our laboratory indicate that ethanol increases both pulmonary and gastrointestinal inflammation as well as susceptibility to infection in burn-injured mice; however, the mechanisms of these responses are not entirely known. Moreover, after burn injury, bacteria and their products leak out of the intestinal lumen and into the bloodstream. These bacteria can disperse throughout the body leading to pulmonary damage, acute lung injury, sepsis, and death. Ethanol in combination with burn injury has been shown to decrease intestinal barrier function greater than either insult alone. Long (210 …

Resveratrol + Ethanol Preconditioning And Neuroprotection, Nastaran Khodaie

Master's Theses

Our lab established that moderate ethanol preconditioning (MEP) for 6 days blocked the Aâ25-35 toxicity in cerebellar mixed cell cultures and It has been shown that MEP cause the up regulation of the pre-survival enzymes such as proxiredoxin2 (PRX2), which suggests MEP can activate the cell survival pathways against upcoming toxins.

This study was performed to verify the possible combinatory effect of ethanol and resveratrol against Aâ25-35 toxicity. Both ethanol and resveratrol sub-protective concentrations were detected against Aâ25-35 in cerebellar mixed cell cultures. The combination of sub-protective levels of ethanol and resveratrol showed the significantly reduction in number of Aâ25-35 …

Investigating The Role Of Α6 And Α4 Containing Neuronal Nicotinic Acetylcholine Receptors In Nicotine And Cocaine Conditioned Place Preference Tests In Mice., Sarah Sanjakdar

Theses and Dissertations

Neuronal nicotinic acetylcholine receptors modulate both cholinergic and non-cholinergic synaptic transmission. Our research concerns α6 and α4 neuronal nicotinic subunits because they often co-assemble with the β2 subunit, which has abundant expression in the CNS and previous work has demonstrated that β2* nAChRs are involved in nicotine and cocaine reward. α6β2* and α4β2* nAChRs are highly expressed in midbrain, which is known to be critical for the incentive salience associated with natural and artificial (drug) reward. Our goal was to assess the role of α6β2* and α4β2* nAChRs in nicotine and cocaine reward using an unbiased conditioned place preference (CPP) …

Evidence For A Non-Genomic Action Of Testosterone In Skeletal Muscle Which May Improve Athletic Performance: Implications For The Female Athlete, J R Dent, D K Fletcher, Michael Mcguigan

Research outputs 2012

This review will focus on the proposed second mode of testosterone action (now termed non-genomic) that appears to occur independently of the traditional transcriptional mechanism in mammalian skeletal muscle cells which may enhance skeletal muscle contractile properties. This mechanism of testosterone action differs from the traditional pathway, originating at the cell membrane, having a rapid onset of action, requiring second messengers to execute its effects and is insensitive to inhibitors of traditional androgen receptor action, transcription and protein synthesis. Importantly, unlike the traditional action of testosterone in skeletal muscle, this non-genomic pathway is shown to have a direct acute effect …

The Emerging Role Of Acyl-Coa Thioesterases And Acyltransferases In Regulating Peroxisomal Lipid Metabolism, Mary Hunt, Marina Siponen, Stefan Alexson

Articles

The importance of peroxisomes in lipid metabolism is now well established and peroxisomes contain approximately 60 enzymes involved in these lipid metabolic pathways. Several acyl-CoA thioesterase enzymes (ACOTs) have been identified in peroxisomes that catalyze the hydrolysis of acyl-CoAs (short-, medium-, long- and very long-chain), bile acid-CoAs, and methyl branched-CoAs, to the free fatty acid and coenzyme A. A number of acyltransferase enzymes, which are structurally and functionally related to ACOTs, have also been identified in peroxisomes, which conjugate (or amidate) bile acid-CoAs and acyl-CoAs to amino acids, resulting in the production of amidated bile acids and fatty acids. The …

Keratinocyte-Targeted Expression Of Human Laminin Γ2 Rescues Skin Blistering And Early Lethality Of Laminin Γ2 Deficient Mice., Tracy L Adair-Kirk, Gail L Griffin, Michelle J Meyer, Diane G Kelley, Jeffrey H Miner, Douglas R Keene, M Peter Marinkovich, J Michael Ruppert, Jouni Uitto, Robert M Senior

Department of Dermatology and Cutaneous Biology Faculty Papers

Laminin-332 is a heterotrimeric basement membrane component comprised of the α3, ß3, and γ2 laminin chains. Laminin-332 modulates epithelial cell processes, such as adhesion, migration, and differentiation and is prominent in many embryonic and adult tissues. In skin, laminin-332 is secreted by keratinocytes and is a key component of hemidesmosomes connecting the keratinocytes to the underlying dermis. In mice, lack of expression of any of the three Laminin-332 chains result in impaired anchorage and detachment of the epidermis, similar to that seen in human junctional epidermolysis bullosa, and death occurs within a few days after birth. To bypass the early …

Administration Of Bone Marrow Derived Mesenchymal Stem Cells Into The Liver: Potential To Rescue Pseudoxanthoma Elasticum In A Mouse Model (Abcc6-/-)., Qiujie Jiang, Shunsuke Takahagi, Jouni Uitto

Department of Dermatology and Cutaneous Biology Faculty Papers

Pseudoxanthoma elasticum (PXE) is a heritable ectopic mineralization disorder caused by loss-of-function mutations in the ABCC6 gene which is primarily expressed in the liver. There is currently no effective treatment for PXE. In this study, we characterized bone marrow derived mesenchymal stem cells (MSCs) and evaluated their ability to contribute to liver regeneration, with the aim to rescue PXE phenotype. The MSCs, isolated from GFP-transgenic mice by magnetic cell sorting, were shown to have high potential for hepatic differentiation, with expression of Abcc6, in culture. These cells were transplanted into the livers of 4-week-old immunodeficient Abcc6⁻/⁻ mice by intrasplenic injection …

Insight Into Animal Cloning And The Food Chain: A Qualitative Examination Of Key Opinion Leaders And A Cross Section Of The Irish Public., Cathal Murphy

Masters

The ability to clone elite breeding animals, aimed at addressing the needs of modern food production, had been earmarked as a possibility for the agricultural sector since the birth of Dolly the sheep in 1996. A ruling by the Food and Drug Administration in the United States in 2008 that permits under-license, the commercial cloning of agricultural animals has seen this possibility realised. No such ruling exists here in Europe, but the FDA policy not to label cloned-derived products, and a history of wariness to food biotechnology in Europe may expedite this debate. With the plethora of issues that cloning …

Severe Lamotrigine Neurotoxicity Treated With Intralipid Emulsion Therapy, Philip W. Moore Do, Megan C. Urquhart Do, Dale L. Mcmillion Do, Keith K. Burkhart Md, Louis R. Cantilena Jr, Md, J Ward Donovan Md

Department of Emergency Medicine

No abstract provided.

Neuron To Microglia Communication; A Study Of Cx3cl1 Signaling Implications In Cognitive Function, Inflammation, And Neurodegeneration, Joshua M. Morganti

USF Tampa Graduate Theses and Dissertations

As a consequence of aging, the brain is subject to chronic neuroinflammatory conditions. The resident immune cells of the brain, microglia, act similarly to peripheral macrophages to protect the brain from insults, infection, and physical trauma. However, without proper regulation of their respective host defense mechanisms, these actions can become neurotoxic. In the healthy brain neurons have several signaling systems that directly interact with microglia in order to maintain a calming influence upon their actions, one of particular interest is the chemokine CX3CL1. This chemokine is found predominantly on neurons, while its cognate receptor CX3CR1 is found exclusively on microglia. …

Maternal Immune Dysregulation In The Pathogenesis Of Neurodevelopmental Disorders: Interleukin-6 As A Central Mechanism And Therapeutic Target Of Flavonoids, Ellisa Carla Parker-Athill

USF Tampa Graduate Theses and Dissertations

Activation of the maternal immune system and resultant maternal cytokine expression due to prenatal infection has been implicated as a significant contributor to the pathology of neuropsychiatric and neurodevelopmental disorders such as schizophrenia and Autism Spectrum Disorder (ASD). Increased maternal interleukin-6 (IL-6) expression, observed clinically and in animal models of prenatal infection, and resultant activation of key signaling pathways, has been shown to be a biological indicator of pathology, and a central component of the pathological mechanism. In animal models of prenatal infection and clinically in pregnancy disorders hallmarked by immunological irregularities and increased IL-6 expression, inhibition of IL-6 has …

Effects Of G-Csf On Monocytes And Neurons: In Vitro And In Vivo Studies In A Mouse Model Of Alzheimer's Disease, Amanda Renee Pennington

USF Tampa Graduate Theses and Dissertations

G-CSF is routinely used to treat neutropenia/leukopenia or to increase hematopoietic stem cell generation in bone marrow donors. G-CSF and its receptor, G-CSFR, are produced by various cell types both in the peripheral circulation and within brain. As a consequence, exogenous administration of G-CSF results in a broad spectrum of effects involving hematopoietic, immune and central nervous systems.

G-CSF administration in a mouse model of Alzheimer's disease (AD) has revealed both cognitive benefits and disease modifying effects: a) decreased Aβ plaque burden, b) increased microgliosis, c) increased neurogenesis and d) improved performance in radial arm water maze (RAWM). In clinical …

Investigating The Impact Of Cd147 And Its Expression On Neurodegenaration And Alzheimer's Disease (Ad), Limbikani J. Kanyenda

Theses: Doctorates and Masters

CD147, also known as basigin, extracellular matrix metalloproteinase inducer, neurothelin, tumour cell-derived collagenase stimulatory factor, M6, HT7, OX47 or gp42, is a transmembrane glycoprotein of the immunoglobulin super-family. It is expressed in many neuronal and non-neuronal tissues with high expression in the hippocampus, pre-frontal cortex, thyroid, heart, early erythroid, amygdala and placenta. This protein is involved in various cellular and biological functions such as lymphocyte migration and maturation, tissue repair, cancer progression, T and B lymphocyte activation and induction of extracellular matrix metalloproteinase. The CD147 protein interacts with with cyclophilin A, cyclophilin B, sterol carrier protein, caveolin-1 and integrins, and …

Cell Cycle Arrest Associated With Anoxia-Induced Quiescence, Anoxic Preconditioning, And Embryonic Diapause In Embryos Of The Annual Killifish Austrofundulus Limnaeus, Camie Lynn Meller, Robert Meller, Roger P. Simon, Kristin M. Culpepper, Jason E. Podrabsky

Biology Faculty Publications and Presentations

Embryos of the annual killifish Austrofundulus limnaeus can enter into dormancy associated with diapause and anoxia-induced quiescence. Dormant embryos are composed primarily of cells arrested in the G1/G0 phase of the cell cycle based on flow cytometry analysis of DNA content. In fact, most cells in developing embryos contain only a diploid complement of DNA, with very few cells found in the S, G2, or M phases of the cell cycle. Diapause II embryos appear to be in a G0-like state with low levels of cyclin D1 and p53. However, the active form of pAKT is high during diapause II. …

Blood-Brain Barrier Abnormalities Caused By Hiv-1 Gp120: Mechanistic And Therapeutic Implications., Jean-Pierre Louboutin, David S Strayer

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

The blood-brain barrier (BBB) is compromised in many systemic and CNS diseases, including HIV-1 infection of the brain. We studied BBB disruption caused by HIV-1 envelope glycoprotein 120 (gp120) as a model. Exposure to gp120, whether acute [by direct intra-caudate-putamen (CP) injection] or chronic [using SV(gp120), an experimental model of ongoing production of gp120] disrupted the BBB, and led to leakage of vascular contents. Gp120 was directly toxic to brain endothelial cells. Abnormalities of the BBB reflect the activity of matrix metalloproteinases (MMPs). These target laminin and attack the tight junctions between endothelial cells and BBB basal laminae. MMP-2 and …

Integrative Gene Regulatory Network Analysis Reveals Light-Induced Regional Gene Expression Phase Shift Programs In The Mouse Suprachiasmatic Nucleus., Haisun Zhu, Rajanikanth Vadigepalli, Rachel Rafferty, Gregory E Gonye, David R Weaver, James S Schwaber

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

We use the multigenic pattern of gene expression across suprachiasmatic nuclei (SCN) regions and time to understand the dynamics within the SCN in response to a circadian phase-resetting light pulse. Global gene expression studies of the SCN indicate that circadian functions like phase resetting are complex multigenic processes. While the molecular dynamics of phase resetting are not well understood, it is clear they involve a "functional gene expression program", e.g., the coordinated behavior of functionally related genes in space and time. In the present study we selected a set of 89 of these functionally related genes in order to further …

Knockdown Of Ki-67 By Dicer-Substrate Small Interfering Rna Sensitizes Bladder Cancer Cells To Curcumin-Induced Tumor Inhibition., Sivakamasundari Pichu, Swapna Krishnamoorthy, Andrei Shishkov, Bi Zhang, Peter Mccue, Biddanda C Ponnappa

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Transitional cell carcinoma (TCC) of the urinary bladder is the most common cancer of the urinary tract. Most of the TCC cases are of the superficial type and are treated with transurethral resection (TUR). However, the recurrence rate is high and the current treatments have the drawback of inducing strong systemic toxicity or cause painful cystitis. Therefore, it would be of therapeutic value to develop novel concepts and identify novel drugs for the treatment of bladder cancer. Ki-67 is a large nucleolar phosphoprotein whose expression is tightly linked to cell proliferation, and curcumin, a phytochemical derived from the rhizome Curcuma …

Decorin Protein Core Affects The Global Gene Expression Profile Of The Tumor Microenvironment In A Triple-Negative Orthotopic Breast Carcinoma Xenograft Model., Simone Buraschi, Thomas Neill, Rick T Owens, Leonardo A Iniguez, George Purkins, Rajanikanth Vadigepalli, Barry Evans, Liliana Schaefer, Stephen C Peiper, Zi-Xuan Wang, Renato V Iozzo

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Decorin, a member of the small leucine-rich proteoglycan gene family, exists and functions wholly within the tumor microenvironment to suppress tumorigenesis by directly targeting and antagonizing multiple receptor tyrosine kinases, such as the EGFR and Met. This leads to potent and sustained signal attenuation, growth arrest, and angiostasis. We thus sought to evaluate the tumoricidal benefits of systemic decorin on a triple-negative orthotopic breast carcinoma xenograft model. To this end, we employed a novel high-density mixed expression array capable of differentiating and simultaneously measuring gene signatures of both Mus musculus (stromal) and Homo sapiens (epithelial) tissue origins. We found that …

Temporal Changes In Innate Immune Signals In A Rat Model Of Alcohol Withdrawal In Emotional And Cardiorespiratory Homeostatic Nuclei., Kate Freeman, Anthony Brureau, Rajanikanth Vadigepalli, Mary M Staehle, Melanie M Brureau, Gregory E Gonye, Jan B Hoek, D Craig Hooper, James S Schwaber

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

BACKGROUND: Chronic alcohol use changes the brain's inflammatory state. However, there is little work examining the progression of the cytokine response during alcohol withdrawal, a period of profound autonomic and emotional upset. This study examines the inflammatory response in the central nucleus of the amygdala (CeA) and dorsal vagal complex (DVC), brain regions neuroanatomically associated with affective and cardiorespiratory regulation in an in vivo rat model of withdrawal following a single chronic exposure.

METHODS: For qRT-PCR studies, we measured the expression of TNF-α, NOS-2, Ccl2 (MCP-1), MHC II invariant chain CD74, and the TNF receptor Tnfrsf1a in CeA and DVC …

Epigenetics: A Possible Mechanism Of Memory, Aliza Grossman Rubenstein

The Science Journal of the Lander College of Arts and Sciences

The following is an excerpt from the introduction to this article: The mind-body connection has fascinated philosophers and scientists for centuries. How is it possible that consciousness arises from a lump of matter known as the brain? How does neurons’ firing affect choice and beliefs? How do the electrochemical properties of the brain allow for the memory of events long after they’ve occurred? One of the most studied of these areas is that of memory. Researchers seek to understand the biological basis behind memory and how that biology is affected in individuals suffering from memory disorders.