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Localization Of Angiotensin Converting Enzyme In Rabbit Cornea And Its Role In Controlling Corneal Angiogenesis In Vivo, Ajay Sharma, Daniel I. Bettis, John W. Cowden, Rajiv R. Mohan

Pharmacy Faculty Articles and Research

Purpose: The renin angiotensin system (RAS) has been shown to modulate vascular endothelial growth factor and angiogenesis. In this study we investigated (i) the existence of the RAS components angiotensin converting enzyme (ACE) and angiotensin II receptors (AT1 and AT2) in the rabbit cornea using in vitro and ex vivo models and (ii) the effect of enalapril, an ACE inhibitor, to inhibit angiogenesis in rabbit cornea in vivo.

Methods: New Zealand White rabbits were used. Cultured corneal fibroblasts and corneal epithelial cells were used for RNA isolation and cDNA preparation using standard molecular biology techniques. PCR was performed to …

Aav Serotype Influences Gene Transfer In Corneal Stroma In Vivo, Ajay Sharma, Jonathan C. K. Tovey, Arkasubhra Ghosh, Rajiv R. Mohan

Pharmacy Faculty Articles and Research

This study evaluated the cellular tropism and relative transduction efficiency of three AAV serotypes, AAV6, AAV8 and AAV9, for corneal gene delivery using mouse cornea in vivo and donor human cornea ex vivo. The AAV6, AAV8 and AAV9 serotypes having AAV2 plasmid encoding for alkaline phosphatase (AP) gene were generated by transfecting HEK293 cell line with pHelper, pARAP4 and pRep/Cap plasmids. Viral vectors (109 vg/μl) were topically applied onto mouse cornea in vivo and human cornea ex vivo after removing the epithelium. Human corneas were processed for transgene delivery at day 5 after viral vector application. Mouse corneas were harvested …

Synthesis, Antiviral And Contraceptive Activities Of Nucleoside-Sodium Cellulose Sulfate Acetate And Succinate Conjugates, Hitesh K. Agarwal, Anil Kumar, Gustavo F. Doncel, Keykavous Parang

Pharmacy Faculty Articles and Research

Chemical conjugates between sodium cellulose sulfate (CS), displaying contraceptive and HIV-entry inhibiting properties, and nucleoside reverse transcriptase inhibitors (NRTIs) (3′-azido-2′,3′-dideoxythymidine (AZT), 3′-fluoro-2′,3′-dideoxythymidine (FLT), or 2',3'-dideoxy-3'-thiacytidine (3TC)) were designed to simultaneously provide contraceptive and anti-HIV activity. Two linkers, acetate and succinate, were used to conjugate the nucleoside analogs with CS. The conjugates containing cellulose sulfate-acetate (CSA) (e.g., AZT-CSA and FLT-CSA) were found to be more potent than CS and other conjugates (e.g., AZT-succinate-CS, and FLT-succinate-CS). The presence of both sulfate and the acetate groups on cellulose were critical for generating maximum anti-HIV activity. In addition to showing equal potency against wild-type …

Proteomic Analysis Of Plasma Exosomes Reveals That Kappa:Lambda Ratio Predicts Severe Acute Graft-Versus-Host Disease, Joseph Alge

MUSC Theses and Dissertations

Background: Acute Graft-Versus-Host disease (acute GVH D) is an often fatal, inflammatory multi-organ disease driven by T cell alloreactivity directed toward host tissues. One of the chief obstacles to improving outcomes of acute GVHD patients is timely diagnosis. Currently, acute GVHD is diagnosed clinically, once the symptoms are fully manifested. However, it is clear that important immunologic events occur prior to the occurrence of symptoms. A biomarker that could predict disease during the asymptomatic period could improve patient outcomes by allowing for earlier intensification of immunosuppressant therapy. Exosomes are an attractive target for acute GVHD biomarker discovery. They contain a …

Radical Hysterectomy With Pelvic Lymphadenectomy: Indications, Technique, And Complications, Rachel A. Ware, John R. Van Nagell Jr.

Obstetrics and Gynecology Faculty Publications

Radical hysterectomy with pelvic lymphadenectomy remains the treatment of choice for women with Stages IA₂ and IB₁carcinoma of the cervix, and selected patients with Stage II endometrial cancer. Improvement in surgical techniqe, administration of prophylactic antibiotics, thromboemolic prophylaxis, and advances in critical care medicine have resulted in lower operative morbidity associated with this procedure. Major urinary tract complications such as ureteral injury or vesico-vaginal fistula are now extremely rare (< 1%). Five-year survival rates following this procedure vary according to a number of clinical and histologic variables, and may be as high as 90% in women without lymph node metastases.

Our Grandparents, Our Parents, Our Future Selves: Optimizing Function In Old Age., Thomas Michael Gill

Center for Policy Research

Most of my research at Yale University School of Medicine over the past several years has focused on identifying older adults at risk of functional decline and disability, identifying events that may precipitate the transition from functional independence to disability, and developing strategies to postpone or reduce frailty and disability. As a result of the Precipitating Events Project (PEP) and other research conducted by the Yale Center on Aging/Pepper Center, we now realize that age is only a proxy for other factors that lead to disability, and that some of these factors can be modified to reduce the risk of …

Marine Algae As A Source Of Photosensitisers For Photodynamic Therapy Of Cancer., Tang Yee Voon

Student Works (2010-2019)

Photodynamic therapy (PDT) involves the intravenous administration of a photosensitiser that preferentially localises in cancerous tissues more than the surrounding normal tissues. Subsequent illumination of photosensitiser generates reactive oxygen species that cause irreversible photo-damage to the cancer cells. To date, most photosensitisers that have been approved for clinical use or are currently in clinical trials are cyclic tetrapyrroles which are derived or inspired by naturally occurring chlorophyll and its degradation products. Some non-tetrapyrrolic photosensitisers have also been found in nature suggesting that there are potential photosensitisers with interesting structures in nature. To this end, this thesis outlines the collection of …

Cytotoxic And Anti-Human Papillomavirus Activites In Selected Vegetables., Maizatul Azmah Ab. Latiff

Student Works (2010-2019)

An appropriate way to control cancer is chemoprevention as a large number of compounds have been observed to prevent the occurrence of cancer and variety of mechanisms exists for producing such protective effects. Numerous epidemiological studies have shown that diets rich in vegetables are associated with a decreased risk of cancer. Chemoprevention involves the use of natural or laboratory made substances to prevent cancer or reduce risk cancer.The E6 oncoprotein from oncogenic Human papillomaviruses (HPVs) has exhibit functions in tumorigenesis, regulation of transcriptions and apoptosis. E6 product from oncogenic viral type like HPV 16 can bind the tumor suppressor p53 …

Cyclin D1 Amplification In Tongue And Buccal Mucosa Squamous Cell Carcinoma., Haydar M. Mahdey

Student Works (2010-2019)

Introduction Oral cancer is a significant health problem worldwide with almost 300,000 new cases are diagnosed each year. Despite the numerous studies done, and even with the best treatment option utilized, more than 50% of patients with oral cancer will experience relapse. In search for better options for prognostication, researches are now focusing on the molecular biology of cancer, for instance in search of reliable tumor markers. Among the markers reported in the literatures, Cyclin D1 is actively studied protein. Cyclin D1 regulates the cell cycle progression by forming a complex with different cyclin dependant kinase. Dysregulation of cyclin D1 …

Mast Cells And Hypoxia Drive Tissue Metaplasia And Heterotopic Ossification In Idiopathic Arthrofibrosis After Total Knee Arthroplasty., Theresa A Freeman, Javad Parvizi, Craig J Dela Valle, Marla J Steinbeck

Department of Orthopaedic Surgery Faculty Papers

ABSTRACT: BACKGROUND: Idiopathic arthrofibrosis occurs in 3-4% of patients who undergo total knee arthroplasty (TKA). However, little is known about the cellular or molecular changes involved in the onset or progression of this condition. To classify the histomorphologic changes and evaluate potential contributing factors, periarticular tissues from the knees of patients with arthrofibrosis were analyzed for fibroblast and mast cell proliferation, heterotopic ossification, cellular apoptosis, hypoxia and oxidative stress. RESULTS: The arthrofibrotic tissue was composed of dense fibroblastic regions, with limited vascularity along the outer edges. Within the fibrotic regions, elevated numbers of chymase/fibroblast growth factor (FGF)-expressing mast cells were …

Chronic Illness And Mental Health Issues, Marlene B. Huff, Kimberly K. Mcclanahan, Hatim A. Omar

Pediatrics Faculty Publications

By 2015, worldwide, 1.2 billion children aged 5-14 years will have some kind of significant chronic disease. Although scientific evidence indicates that children with chronic illness have more mental health issues than their healthy peers, many controversies and gaps in the literature exist. It is imperative that an understanding of the effects of chronic illness upon the mental health status of children and adolescent be undertaken. This article uses a biopsychosocial perspective to investigate the connection between chronic illness and mental health. The intent of the article is to suggest ways that medical and mental health professionals can provide services …

Quality Of Life And Adolescents In Rural Kentucky, Hatim A. Omar, Søren Ventegodt, Joav Merrick

Pediatrics Faculty Publications

In many rural areas in Kentucky, adolescents lack the basic assets for a good quality of life, such as having caring adults, a safe place and useful activities after school. In this chapter we analyze data from middle and high school students referred to a comprehensive school based health promotion center (SBHPC). From August 2006 to February 2008, a total of 382 students (200 female, 182 male, aged 12-18 years) were referred to the SBHPC for help. Only two (0.5%) students had two parents living with them and 12 (3.1 %) had safe, organized after school activities. 19.9% of the …

Robustness Of The Healthcare Utilization Results From The Rotavirus Efficacy And Safety Trial (Rest) Evaluating The Human-Bovine (Wc3) Reassortant Pentavalent Rotavirus Vaccine (Rv5), Robbin Itzler, Gary Koch, David O. Matson, Leif Gothefors, Pierre Van Damme, Mark J. Dinubile, Penny M. Heaton

Community & Environmental Health Faculty Publications

Background: The Rotavirus Efficacy and Safety Trial was a placebo-controlled Phase III study that evaluated the safety and efficacy of a three-dose pentavalent rotavirus vaccine (RV5) including its effect on healthcare utilization for rotavirus gastroenteritis (RVGE). The per-protocol (PP) analyses, which counted events occurring 14 days after dose 3 among infants without protocol violations, have already been published. This paper evaluates the consistency of the healthcare utilization results based on the modified intention to treat (MITT) analyses with the PP analyses. The MITT analyses include all infants receiving at least one dose of vaccine or placebo and follow-up begins after …

Hereditary 1,25-Dihydroxyvitamin D-Resistant Rickets With Alopecia Resulting From A Novel Missense Mutation In The Dna-Binding Domain Of The Vitamin D Receptor., Peter J. Malloy, Jining Wang, Tarak Srivastava, David Feldman

Manuscripts, Articles, Book Chapters and Other Papers

The rare genetic recessive disease, hereditary vitamin D resistant rickets (HVDRR), is caused by mutations in the vitamin D receptor (VDR) that result in resistance to the active hormone 1,25-dihydroxyvitamin D(3) (1,25(OH)(2)D(3) or calcitriol). In this study, we examined the VDR from a young boy with clinical features of HVDRR including severe rickets, hypocalcemia, hypophosphatemia and partial alopecia. The pattern of alopecia was very unusual with areas of total baldness, adjacent to normal hair and regions of scant hair. The child failed to improve on oral calcium and vitamin D therapy but his abnormal chemistries and his bone X-rays normalized …

Activation Of Tumor Cell Death Program By Targeting The Ubiquitin-Proteasome Pathway: Significance In Cancer Treatment And Prevention, Michael Joseph Frezza

Wayne State University Dissertations

ACTIVATION OF TUMOR CELL DEATH PROGRAM BY TARGETING THE UBIQUITIN-PROTEASOME PATHWAY: SIGNIFICANCE IN CANCER TREATMENT AND PREVENTION

by

MICHAEL FREZZA

August 2010

Advisor: Dr. Q. Ping Dou

Major: Cancer Biology

Degree: Doctor of Philosophy

The ubiquitin-proteasome pathway serves as a quality control mechanism to regulate the degradation of intracellular proteins involved in a wide array of cellular processes including tumorigeneis. Thus targeting key features of protein turnover responsible for the growth and proliferation of cancer have emerged as a favorable approach in cancer therapy. Both in vitro and in vivo experimental and clinical results have demonstrated the potential use of …

Defensins In Ocular Immunity, Minhao Wu

Wayne State University Dissertations

Corneal infection with P. aeruginosa results in corneal perforation in susceptible

B6, but not resistant BALB/c mice. This study explored their role mBD 1-4 in corneal

infection, and their potential synergy. Immunostaining and real-time RT-PCR data

demonstrated that their expression was either constitutive (mBD1 and mBD2) or

inducible (mBD3 and mBD4) in normal BALB/c and B6 corneas, and disparately

regulated in BALB/c vs B6 corneas after infection. Knock down studies using siRNA

treatment indicated that mBD2 and mBD3, but neither mBD1 nor mBD4, is required in

ocular defense. Moreover, in vivo studies demonstrated individual and combined effects

of mBD2 and …

Prenatal Beta-Endorphin As An Early Predictor Of Postpartum Depressive Symptoms In Euthymic Women, Ilona S. Yim, Laura M. Glynn, Christine Dunkel Schetter, Calvin J. Hobel, Aleksandra Chicz-Demet, Curt A. Sandman

Psychology Faculty Articles and Research

After delivery, many women experience symptoms of postpartum depression (PPD), and early identification of women at risk is therefore important. The opioid peptide [beta]-endorphin has been implicated in non-puerperal depression but its role in the development of PPD is unknown.

Interaction Of The Mu-Opioid Receptor With Gpr177 (Wntless) Inhibits Wnt Secretion: Potential Implications For Opioid Dependence., Jay Jin, Saranya Kittanakom, Victoria Wong, Beverly A S Reyes, Elisabeth J Van Bockstaele, Igor Stagljar, Wade Berrettini, Robert Levenson

Department of Neurosurgery Faculty Papers

BACKGROUND: Opioid agonist drugs produce analgesia. However, long-term exposure to opioid agonists may lead to opioid dependence. The analgesic and addictive properties of opioid agonist drugs are mediated primarily via the mu-opioid receptor (MOR). Opioid agonists appear to alter neuronal morphology in key brain regions implicated in the development of opioid dependence. However, the precise role of the MOR in the development of these neuronal alterations remains elusive. We hypothesize that identifying and characterizing novel MOR interacting proteins (MORIPs) may help to elucidate the underlying mechanisms involved in the development of opioid dependence. RESULTS: GPR177, the mammalian ortholog of Drosophila …

Neuroaids In Africa, Kevin Robertson, Jeff Liner, James Hakim, Jean-Louis Sankalé, Igor Grant, Scott Letendre, David Clifford, Amadou Gallo Diop, Assan Jaye, Georgette Kanmogne, Alfred Njamnshi, T. Dianne Langford, Tufa Gemechu Weyessa, Charles Wood, Mwanza Banda, Mina Hosseinipour, Ned Sacktor, Noeline Nakasuja, Paul Bangirana, Robert Paul, John Joska, Joseph Wong, Michael Boivin, Penny Holding, Betsy Kammerer, Annelies Van Rie, Prudence Ive, Avindra Nath, Kathy Lawler, Clement Adebamowo, Walter Royal Iii, Jeymohan Joseph

Nebraska Center for Virology: Faculty Publications

In July 2009, the Center for Mental Health Research on AIDS at the National Institute of Mental Health organized and supported the meeting “NeuroAIDS in Africa.” This meeting was held in Cape Town, South Africa, and was affiliated with the 5th IAS Conference on HIV Pathogenesis, Treatment and Prevention. Presentations began with an overview of the epidemiology of HIV in sub-Saharan Africa, the molecular epidemiology of HIV, HIV-associated neurocognitive disorders (HANDs), and HAND treatment. These introductory talks were followed by presentations on HAND research and clinical care in Botswana, Cameroon, Ethiopia, The Gambia, Kenya, Malawi, Nigeria, Senegal, South Africa, Uganda, …

Functional Properties Of The Hiv-1 Subtype C Envelope Glycoprotein Associated With Mother-To-Child Transmission, Hong Zhang, Marzena Rola, John T. West, Damien C. Tully, Piotr Kubis, Jun He, Chipepo Kankasa, Charles Wood

Nebraska Center for Virology: Faculty Publications

Understanding the properties of viruses capable of establishing infection during perinatal transmission of HIV-1 is critical for designing effective means of limiting transmission. We previously demonstrated that the newly transmitted viruses (in infant) were more fit in growth, as imparted by their envelope glycoproteins, than those in their corresponding mothers. Here, we further characterized the viral envelope glycoproteins from six mother-infant transmission pairs and determined whether any specific envelope functions correlate with HIV-1 subtype C perinatal transmission. We found that most newly transmitted viruses were less susceptible to neutralization by their maternal plasma compared to contemporaneous maternal viruses. However, the …

Chronology And Evolution Of The Hiv-1 Subtype C Epidemic In Ethiopia, Damien C. Tully, Charles Wood

Nebraska Center for Virology: Faculty Publications

Objective—To reconstruct the onset date and evolutionary history of the HIV-1 subtype C epidemic in Ethiopia - one of the earliest recorded subtype C epidemics in the world.

Design—HIV-1 C env sequences with a known sampling year isolated from HIV-1 positive patients from Ethiopia between 1984 and 2003.

Methods—Evolutionary parameters including origin and demographic growth patterns were estimated using a Bayesian coalescent-based approach under either strict or relaxed molecular clock models.

Results—Bayesian evolutionary analysis indicated a most recent common ancestor date of 1965 with three distinct epidemic growth phases. Regression analysis of root-to-tip distances revealed a highly similar estimate for …

Enhancement Of Autophagy During Lytic Replication By The Kaposi’S Sarcoma-Associated Herpesvirus Replication And Transcription Activator, Hui-Ju Wen, Zhilong Yang, You Zhou, Charles Wood

Nebraska Center for Virology: Faculty Publications

Autophagy is one of two major degradation systems in eukaryotic cells. The degradation mechanism of autophagy is required to maintain the balance between the biosynthetic and catabolic processes and also contributes to defense against invading pathogens. Recent studies suggest that a number of viruses can evade or subvert the host cell autophagic pathway to enhance their own replication. Here, we investigated the effect of autophagy on the KSHV (Kaposi’s sarcoma-associated herpesvirus) life cycle. We found that the inhibition of autophagy reduces KSHV lytic reactivation from latency, and an enhancement of autophagy can be detected during KSHV lytic replication. In addition, …

Increased Dendrite Branching In Aβpp/Ps1 Mice And Elongation Of Dendrite Arbors By Fasudil Administration, Brian A. Couch, George J. Demarco, Shannon L. Gourley, Anthony J. Koleske

School of Biological Sciences: Faculty Publications

Amyloid-β (Aβ) overproduction and dendrite arbor atrophy are hallmarks of Alzheimer’s disease. The RhoA GTPase (Rho) signals through Rho kinase (ROCK) to control cytoskeletal dynamics and regulate neuron structure. Hyperactive Rho signaling destabilizes neurons leading to dendritic regression that can be rescued by genetic or pharmacological reduction of ROCK signaling. To understand what effect reduced ROCK signaling has on the dendrite arbors of mice that overproduce Aβ, we administered the ROCK inhibitor fasudil to AβPP/PS1 transgenic mice. We report that increased dendrite branching occurs in AβPP/PS1 mice and that fasudil promotes …

Synaptic Clustering Of Psd-95 Is Regulated By C-Abl Through Tyrosine Phosphorylation, Karen Perez De Arce, Lorena Varela-Nallar, Olivia Farias, Alejandra Cifuentes, Paulina Bull, Brian A. Couch, Anthony J. Koleske, Nibaldo C. Inestrosa, Alejandra R. Alvarez

School of Biological Sciences: Faculty Publications

The c-Abl tyrosine kinase is present in mouse brain synapses, but its precise synaptic function is unknown. We found that c-Abl levels in the rat hippocampus increase postnatally, with expression peaking at the first postnatal week. In 14 d in vitro hippocampal neuron cultures, c-Abl localizes primarily to the postsynaptic compartment, in which it colocalizes with the postsynaptic scaffold protein postsynaptic density protein-95 (PSD-95) in apposition to presynaptic markers. c-Abl associates with PSD-95, and chemical or genetic inhibition of c-Abl kinase activity reduces PSD-95 tyrosine phosphorylation, leading to reduced PSD-95 clustering and reduced synapses in treated neurons. c-Abl can phosphorylate …

Population Genetic Analysis Of Large Sequence Polymorphisms In Plasmodium Falciparum Blood-Stage Antigens, A.D. Ahouidi, A.K. Bei, D.E. Neafsey, O. Sarr, S. Volkman, D. Milner, J. Cox-Singh, M.U. Ferreira, O. Ndir, Zul Premji, S. Mboup, M.T. Duraisingh

Pathology, East Africa

Plasmodium falciparum, the causative agent of human malaria, invades host erythrocytes using several proteins on the surface of the invasive merozoite, which have been proposed as potential vaccine candidates. Members of the multi-gene PfRh family are surface antigens that have been shown to play a central role in directing merozoites to alternative erythrocyte receptors for invasion. Recently, we identified a large structural polymorphism, a 0.58 Kb deletion, in the C-terminal region of the PfRh2b gene, present at a high frequency in parasite populations from Senegal. We hypothesize that this region is a target of humoral immunity. Here, by analyzing 371 …

Differential Genome-Wide Array–Based Methylation Profiles In Prognostic Subsets Of Chronic Lymphocytic Leukemia, Meena Kanduri, Nicola Cahill, Hanna Göransson, Camilla Enström, Fergus Ryan, Anders Isaksson, Richard Rosenquist

Articles

Global hypomethylation and regional hypermethylation are well-known epigenetic features of cancer; however, in chronic lymphocytic leukemia (CLL), studies on genome-wide epigenetic modifications are limited. Here, we analyzed the global methylation profiles in CLL, by applying high-resolution methylation microarrays (27 578 CpG sites) to 23 CLL samples, belonging to the immunoglobulin heavy-chain variable (IGHV) mutated (favorable) and IGHV unmutated/IGHV3-21 (poor-prognostic) subsets. Overall, results demonstrated significant differences in methylation patterns between these subgroups. Specifically, in IGHV unmutated CLL, we identified methylation of 7 known or candidate tumor suppressor genes (eg, VHL, ABI3, and IGSF4) as well as 8 unmethylated genes involved in …

Differential Gene Expression Profile Of Retinoblastoma Compared To Normal Retina., Arupa Ganguly, Carol L Shields

Wills Eye Hospital Papers

PURPOSE: The retinoblastoma gene (RB1) is a tumor suppressor gene that was first discovered in a rare ocular pediatric tumor called retinoblastoma (RB). The RB1 gene is essential for normal progression through the cell cycle and exerts part of its function through the family of transcription factors (E2F) and many other intermediaries. In the absence of normal RB1, genomic instability and chromosomal aberrations accumulate, leading to tumor initiation, progression, and ultimately metastasis. The purpose of this report was to identify the molecular pathways that are deregulated in retinoblastoma.

METHODS: We compared gene expression signatures of matched normal retinal tissue and …

3d Visualization Of Hiv Virions By Cryoelectron Tomography, Jun Liu, Elizabeth R Wright, Hanspeter Winkler

Faculty, Staff and Student Publications

The structure of the human immunodeficiency virus (HIV) and some of its components have been difficult to study in three-dimensions (3D) primarily because of their intrinsic structural variability. Recent advances in cryoelectron tomography (cryo-ET) have provided a new approach for determining the 3D structures of the intact virus, the HIV capsid, and the envelope glycoproteins located on the viral surface. A number of cryo-ET procedures related to specimen preservation, data collection, and image processing are presented in this chapter. The techniques described herein are well suited for determining the ultrastructure of bacterial and viral pathogens and their associated molecular machines …

Subacute Neural Stem Cell Therapy For Traumatic Brain Injury, Mikhail Bogdanov, Philip N Heacock, William Dowhan

Faculty, Staff and Student Publications

A protocol is described using lipid mutants and thiol-specific chemical reagents to study lipid-dependent and host-specific membrane protein topogenesis by the substituted-cysteine accessibility method as applied to transmembrane domains (SCAM). SCAM is adapted to follow changes in membrane protein topology as a function of changes in membrane lipid composition. The strategy described can be adapted to any membrane system.

More Than Synaptic Plasticity: Role Of Nonsynaptic Plasticity In Learning And Memory, Riccardo Mozzachiodi, John H Byrne

Faculty, Staff and Student Publications

Decades of research on the cellular mechanisms of memory have led to the widely held view that memories are stored as modifications of synaptic strength. These changes involve presynaptic processes, such as direct modulation of the release machinery, or postsynaptic processes, such as modulation of receptor properties. Parallel studies have revealed that memories might also be stored by nonsynaptic processes, such as modulation of voltage-dependent membrane conductances, which are expressed as changes in neuronal excitability. Although in some cases nonsynaptic changes can function as part of the engram itself, they might also serve as mechanisms through which a neural circuit …