Genetic Processes Commons^™

Chemosensitization Of Hepatocellular Carcinoma To Gemcitabine By Non-Invasive Radiofrequency Field-Induced Hyperthermia, Mustafa Raoof

Dissertations and Theses (Open Access)

Gemcitabine is a potent nucleoside analogue against solid tumors however drug resistance rapidly emerges. Removal of gemcitabine incorporated in the DNA by repair mechanisms could potentially contribute to resistance in chemo-refractory solid tumors. In this study, we evaluated homologous recombination repair of gemcitabine-stalled replication forks as a potential mechanism contributing to resistance. We also studied the effect of hyperthermia on homologous recombination pathway to explain the previously reported synergy between gemcitabine and hyperthermia. We found that hyperthermia degrades and inhibits localization of Mre11 to gemcitabine-stalled replication forks. Furthermore, gemcitabine-treated cells that were also treated with hyperthermia demonstrate a prolonged passage …

Advancing Our Understanding Of The Inheritance And Transmission Of Pectus Excavatum, Lisa Horth, Michael W. Stacey, Virginia K. Proud, Kara Segna, Chelsea Rutherford, Donald Nuss, Robert E. Kelly

Bioelectrics Publications

Pectus excavatum is the most common congenital chest wall abnormality expressed in children, yet its inheritance is poorly understood. Here we present the first comprehensive assessment of the inheritance of this disorder. After evaluating 48 pedigrees and 56 clinical traits of probands and family members, we find strong evidence of autosomal recessive, genetic control for this disorder. Additionally there is likely more than one pectus disease-associated allele, as well as a relatively large number of disease allele carriers in the human population. Some clinical traits appear important and may serve as reliable indicators for predicting the likelihood of pectus excavatum …

Activity Of Analogs Of Anticancer Drugs On The Serine Protease Enzymes Subtilisin And Chymotrypsin, Dhatri Ravipati

Masters Theses & Specialist Projects

The anticancer activity of several platinum compounds is due to the formation of complexes with DNA. We hypothesize that the size and shape of the platinum compounds would impact interaction with proteins, and these interactions may be partly responsible for the anticancer activity. Chymotrypsin and subtilisin are serine proteases that have a histidine residue in the active site. We are investigating the inhibition of the digestive enzymes chymotrypsin and subtilisin by analogs of the anticancer drug cisplatin and trying to discern trends in the inhibition as the active site residues vary. In our research, we found that the enzyme subtilisin …

Enforced Expression Of Tbx1 In Fetal Thymic Epithelial Cells Antagonizes Thymus Organogenesis, Kim T. Cardenas

Dissertations and Theses (Open Access)

Enforced expression of Tbx1 in fetal thymic epithelial cells antagonizes

thymus organogenesis

Kim T. Cardenas

The thymus and parathyroid glands originate from organ-specific domains of 3rd pharyngeal pouch (PP) endoderm. At embryonic day 11.5 (E11.5), the ventral thymus and dorsal parathyroid domains can be identified by Foxn1 and Gcm2 expression respectively. Neural crest cells, (NCCs) play a role in regulating patterning of 3rd PP endoderm. In addition, pharyngeal endoderm influences fate determination via secretion of Sonic hedgehog (Shh), a morphogen required for Gcm2 expression and generation of the parathyroid domain. Gcm2 is a downstream target of the transcription factor Tbx1, …

Effect Of Aging On Cellular Mechanotransduction, Miaozong Wu, Jacqueline Fannin, Kevin M. Rice, Bin Wang, Eric R. Blough

MIIR Faculty Research

Aging is becoming a critical heath care issue and a burgeoning economic burden on society. Mechanotransduction is the ability of the cell to sense, process, and respond to mechanical stimuli and is an important regulator of physiologic function that has been found to play a role in regulating gene expression, protein synthesis, cell differentiation, tissue growth, and most recently, the pathophysiology of disease. Here we will review some of the recent findings of this field and attempt, where possible, to present changes in mechanotransduction that are associated with the aging process in several selected physiological systems, including musculoskeletal, cardiovascular, neuronal, …

Age-Associated Alterations In The F344xbn Rat Heart And The Efficacy Of Chronic Acetaminophen Ingestion As A Therapeutic Approach, Sunil K. Kakarla

Theses, Dissertations and Capstones

Despite advances in therapeutic and diagnostic strategies cardiovascular disease still remains the leading cause of death in older people. Recent studies suggest that age- related elevations in oxidative stress are associated with increases in cardiac apoptosis and compensatory hypertrophy of the remaining cardiomyocytes. Acetaminophen has been shown to exhibit cardioprotective effects following ischemia-reperfusion injury by acting as an antioxidant. Here, we investigate the molecular mechanisms underlying aging associated cardiac remodeling in male F344XBN rats and examine the efficacy of chronic acetaminophen ingestion as a therapeutic approach.

Aging in male F344XBN rats is characterized by a significant increase in heart size, …

Muscle Plasticity And Intramuscular Signaling In The Insulin-Resistant Obese Zucker Rat, Anjaiah Katta

Theses, Dissertations and Capstones

The ability to increase skeletal muscle mass may have important implications for the treatment of insulin resistance (IR) and diabetes [1-3]. Recent data suggest that IR muscle may adapt differently than normal muscle; however, molecular mechanism(s) responsible for this finding are not well understood [4]. Herein, we investigate the molecular mechanisms underlying the skeletal muscle remodeling in the IR Obese Zucker (OZ) rat.

The OZ rat is characterized by skeletal muscle insulin resistance, hyperglycemia, and hyperlipidemia. Compared to LZ rats, our data demonstrate that soleus muscle hypertrophy was significantly attenuated in the OZ rats after 3-weeks of muscle overload and …

Altered Self-Assembly And Apatite Binding Of Amelogenin Induced By N-Terminal Proline Mutation, Li Zhu, Vuk Uskoković, Thuan Le, Pamela Denbesten, Yulei Huang, Stefan Habelitz, Wu Li

Pharmacy Faculty Articles and Research

Objective—A single Pro-70 to Thr (p.P70T) mutation of amelogenin is known to result in hypomineralized amelogenesis imperfecta (AI). This study aims to test the hypothesis that the given mutation affects the self-assembly of amelogenin molecules and impairs their ability to conduct the growth of apatite crystals.

Design—Recombinant human full-length wild-type (rh174) and p.P70T mutated amelogenins were analyzed using dynamic light scattering (DLS), protein quantification assay and atomic force microscopy (AFM) before and after the binding of amelogenins to hydroxyapatite crystals. The crystal growth modulated by both amelogenins in a dynamic titration system was observed using AFM.

Results—As …

Hydrolysis Of Amelogenin By Matrix Metalloprotease-20 Accelerates Mineralization In Vitro, Vuk Uskoković, Feroz Khan, Haichuan Liu, Halina Ewa Witkowska, Li Zhu, Wu Li, Stefan Habelitz

Pharmacy Faculty Articles and Research

In the following respects, tooth enamel is a unique tissue in the mammalian body: (a) it is the most mineralized and hardest tissue in it comprising up to 95 wt% of apatite; (b) its microstructure is dominated by parallel rods composed of bundles of 40 – 60 nm wide apatite crystals with aspect ratios reaching up to 1:10,000 and (c) not only does the protein matrix that gives rise to enamel guides the crystal growth, but it also conducts its own degradation and removal in parallel. Hence, when mimicking the process of amelogenesis in vitro, crystal growth has to …

Biomimetic Precipitation Of Uniaxially Grown Calcium Phosphate Crystals From Full-Length Human Amelogenin Sols, Vuk Uskoković, Wu Li, Stefan Habelitz

Pharmacy Faculty Articles and Research

Human dental enamel forms over a period of 2 – 4 years by substituting the enamel matrix, a protein gel mostly composed of a single protein, amelogenin with fibrous apatite nanocrystals. Self-assembly of a dense amelogenin matrix is presumed to direct the growth of apatite fibers and their organization into bundles that eventually comprise the mature enamel, the hardest tissue in the mammalian body. This work aims to establish the physicochemical and biochemical conditions for the synthesis of fibrous apatite crystals under the control of a recombinant fulllength human amelogenin matrix in combination with a programmable titration system. The growth …

Teratology Primer-2nd Edition (7/9/2010), Sura Alwan, Steven B. Bleyl, Robert L. Brent, Christina D. Chambers, George P. Daston, Elaine M. Faustman, Richard H. Finnell, F. Clarke Fraser, Jan M. Freidman, Adriane Fugh-Berman, John M. Graham, Jr., Barbara F. Hales, Deborah K. Hansen, Lewis B. Holmes, Ronald D. Hood, Robert J. Kavlock, Thomas B. Knudsen, Joseph Lary, Donald R. Mattison, Richard K. Miller, James L. Mills, Janine E. Polifka, Sonja A. Rasmussen, Bernard Robaire, John M. Rogers, Gary C. Schoenwolf, Anthony R. Scialli, Gary M. Shaw, Amar V. Singh, William Slikker, Jr., Ann P. Streissguth, Melissa S. Tassinari, Janet Uriu-Adams, Charles V. Vorhees, Elora J. Weringer

Department of Pediatrics Faculty Papers

Foreword:

What is Teratology?

“What a piece of work is an embryo!” as Hamlet might have said. “In form and moving how express and admirable! In complexity how infinite!” It starts as a single cell, which by repeated divisions gives rise to many genetically identical cells. These cells receive signals from their surroundings and from one another as to where they are in this ball of cells —front or back, right or left, headwards or tailwards, and what they are destined to become. Each cell commits itself to being one of many types; the cells migrate, combine into tissues, or …

Systems Biology Approach To Identifying Host Interactive Pathways Modulating The Severity Of Streptococcal Sepsis, Nourtan Fatthy Abdeltawab

Theses and Dissertations (ETD)

Clinical outcomes of infectious diseases are controlled by complex interactions between the host and the pathogen. Epidemiological, genetic and molecular studies in my mentor’s laboratory provided evidence that in invasive Group A streptococcal (GAS) infections, genetic variations in both bacteria and patients influenced the severity of GAS sepsis. Allelic variations in class II human leukocyte antigens (HLA) contributed significantly to differences in the severity of group A streptococcal sepsis caused by the same virulent strain of the bacteria. HLA class II molecules present streptococcal superantigens (SAgs) to T cells, and variations in HLA class II molecules can strongly influence SAg …

Investigating The Role Of P311 In The Hypertrophic Scar, Jianglin Tan, Xu Peng, Gaoxing Luo, Bing Ma, Chuan Cao, Weifeng He, Shunzong Yuan, Shirong Li, John A. Wilkins, Jun Wu

MIIR Faculty Research

The mechanisms of hypertrophic scar formation are not fully understood. We previously screened the differentially expressed genes of human hypertrophic scar tissue and identified P311 gene as upregulated. As the activities of P311 in human fibroblast function are unknown, we examined the distribution of it and the effects of forced expression or silencing of expression of P311. P311 expression was detected in fibroblast-like cells from the hypertrophic scar of burn injury patients but not in peripheral blood mononuclear cells, bone marrow mesenchymal stem cells, epidermal cells or normal skin dermal cells. Transfection of fibroblasts with P311 gene stimulated the expression …

Epigenetics: Blurring The Line Between Nature And Nurture, Elizabeth H. Rose

CMC Senior Theses

This long-standing nature versus nurture debate is cited in behavioral and physical expressions of disease dysfunctions, resiliencies, and recovery. Their purposes are noted both in scientific pursuits as well as literature. This discourse has been particularly intense in the fields of psychology, psychiatry, and biology where there is a long history of scientists’ attempts to disprove or discredit others’ intellectual and professional measures. Interestingly, recent advances in the neurosciences and genetic technologies have brought these fields closer together with a new focus – the interactional relationship between nature and nurture – epigenetics.

Aging And Environmental Exposures Alter Tissue-Specific Dna Methylation Dependent Upon Cpg Island Context, Brock C. Christensen, E Andres Houseman, Carmen J. Marsit, Shichun Zheng, Margaret R. Wrensch, Joseph L. Wiemels, Heather H. Nelson, Margaret R. Karagas

Dartmouth Scholarship

Epigenetic control of gene transcription is critical for normal human development and cellular differentiation. While alterations of epigenetic marks such as DNA methylation have been linked to cancers and many other human diseases, interindividual epigenetic variations in normal tissues due to aging, environmental factors, or innate susceptibility are poorly characterized. The plasticity, tissue-specific nature, and variability of gene expression are related to epigenomic states that vary across individuals. Thus, population-based investigations are needed to further our understanding of the fundamental dynamics of normal individual epigenomes. We analyzed 217 non-pathologic human tissues from 10 anatomic sites at 1,413 autosomal CpG loci …

Genetic Mapping Of Secretion And Functional Determinants Of The Vibrio Cholerae Tcpf Colonization Factor, Shelly J. Krebs, Thomas J. Kirn, Ronald K. Taylor

Dartmouth Scholarship

Colonization of the human small intestine by Vibrio cholerae requires the type IV toxin-coregulated pilus (TCP). TcpF, which is encoded within the tcp operon, is secreted from the bacterial cell by the TCP apparatus and is also essential for colonization. Bacteria lacking tcpF are deficient in colonization, and anti-TcpF antibodies are protective in the infant mouse cholera model. In order to elucidate the regions of the protein that are required for secretion through the TCP apparatus and for its function in colonization, random mutagenesis of tcpF was performed. Analysis of these mutants suggests that multiple regions throughout the protein influence …

Identification And Characterization Of Novel Sir3/Mecp2-Chromatin Interactions, Nicholas L. Adkins

Theses, Dissertations and Capstones

The eukaryotic genome is packaged into chromosomes that are made up of a highly organized and heavily regulated structure called chromatin. The proteins involved in the compaction of DNA into this condensed state are mostly understood at the level of the structure of the nucleosome. The higher order arrangement of chromatin and how it effects gene regulation is only partially understood and characterized. The compaction of nucleosomal arrays into 30-nm and higher structures are partially the responsibility of architectural, or structural, chromatin associated proteins. The following dissertation analyzes the individual chromatin contributions of two well studied architectural proteins, the yeast …

Adenovirus E4orf4 Induces Hpv-16 Late L1 Mrna Production, Monica Somberg, Margaret Rush, Joanna Fay, Fergus Ryan, Helen Lambkin, Göran Akusjärvi, Stefan Schwartz

Articles

The adenovirus E4orf4 protein regulates the switch from early to late gene expression during the adenoviral replication cycle. Here we report that overexpression of adenovirus E4orf4 induces human papillomavirus type 16 (HPV-16) late gene expression from subgenomic expression plasmids. E4orf4 specifically overcomes the negative effects of two splicing silencers at the two late HPV-16 splice sites SD3632 and SA5639. This results in the production of HPV-16 spliced L1 mRNAs. We show that the interaction of E4orf4 with protein phosphatase 2A (PP2A) is necessary for induction of HPV-16 late gene expression. Also an E4orf4 mutant that fails to bind the cellular …

Retinoid X Receptor And Peroxisome Proliferator-Activated Receptor-Gamma Agonists Cooperate To Inhibit Matrix Metalloproteinase Gene Expression, Peter S. Burrage, Adam C. Schmucker, Yanqing Ren, Michael B. Sporn, Constance E. Brinckerhoff

Dartmouth Scholarship

We recently described the ability of retinoid X receptor (RXR) ligand LG100268 (LG268) to inhibit interleukin-1-beta (IL-1-β)-driven matrix metalloproteinase-1 (MMP-1) and MMP-13 gene expression in SW-1353 chondrosarcoma cells. Other investigators have demonstrated similar effects in chondrocytes treated with rosiglitazone, a ligand for peroxisome proliferator-activated receptor-gamma (PPARγ), for which RXR is an obligate dimerization partner. The goals of this study were to evaluate the inhibition of IL-1--induced expression of MMP-1andMMP-13 by combinatorial treatment with RXR and PPAR  ligands and to investigate the molecular mechanisms of this inhibition.

Transcriptional Regulation Network Analysis Of The Hypertension-Perturbed Nucleus Tractus Solitarius, Gregory E. Gonye, Rajanikanth Vadigepalli, Haiping Hao, James S. Schwaber

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Poster Presentation.

Multi-Scale Modeling Of Angiotensin Ii Induced Neuronal Regulatory Mechanisms In The Brain, Rajanikanth Vadigepalli

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Poster Presentation.

Enzymatic Processing Of Amelogenin During Continuous Crystallization Of Apatite, Vuk Uskoković, M.-K. Kim, W. Li, S. Habelitz

Pharmacy Faculty Articles and Research

Dental enamel forms through a protein-controlled mineralization and enzymatic degradation with a nanoscale precision that new engineering technologies may be able to mimic. Recombinant fulllength human amelogenin (rH174) and a matrix-metalloprotease (MMP-20) were employed in a pHstat titration system that enabled a continuous supply of calcium and phosphate ions over several days, mimicking the initial stages of matrix processing and crystallization in enamel in-vitro. Effects on the self-assembly and crystal growth from a saturated aqueous solution containing 0.4 mg/ml rH174 and MMP-20 with the weight ratio of 1:1000 with respect to rH174 were investigated. A transition from nanospheres to fibrous …

A Novel Runx2 Missense Mutation Predicted To Disrupt Dna Binding Causes Cleidocranial Dysplasia In A Large Chinese Family With Hyperplastic Nails, Shaohua Tang, Qiyu Xu, Xueqin Xu, Jicheng Du, Xuemei Yang, Yusheng Jiang, Xiaoqin Wang, Nancy Speck, Taosheng Huang

Dartmouth Scholarship

Background: Cleidocranial dysplasia (CCD) is a dominantly inherited disease characterized by hypoplastic or absent clavicles, large fontanels, dental dysplasia, and delayed skeletal development. The purpose of this study is to investigate the genetic basis of Chinese family with CCD.

Methods: Here, a large Chinese family with CCD and hyperplastic nails was recruited. The clinical features displayed a significant intrafamilial variation. We sequenced the coding region of the RUNX2 gene for the mutation and phenotype analysis.

Results: The family carries a c.T407C (p.L136P) mutation in the DNA- and CBFβ-binding Runt domain of RUNX2. Based on the crystal structure, we predict this …

Direct Inhibition Of Cdk9 Blocks Hiv-1 Replication Without Preventing T Cell Activation In Primary Human Peripheral Blood Lymphocytes, Dominic Salerno, Muneer G Hasham, Renee Marshall Demarest, Judit Garriga, Alexander Y Tsygankov, Xavier Graña

Rowan-Virtua School of Osteopathic Medicine Departmental Research

HIV-1 transcription is essential for the virus replication cycle. HIV-1 Tat is a viral transactivator that strongly stimulates the processivity of RNA polymerase II (RNAPII) via recruitment of the cyclin T1/CDK9 positive transcription elongation factor, which phosphorylates the C-terminal domain (CTD) of RNAPII. Consistently, HIV-1 replication in transformed cells is very sensitive to direct CDK9 inhibition. Thus, CDK9 could be a potential target for anti-HIV-1 therapy. A clearer understanding of the requirements for CDK9 activity in primary human T cells is needed to assess whether the CDK9-dependent step in HIV-1 transcription can be targeted clinically. We have investigated the effects …

Chromosomal Microdeletions And Genes' Functions: A Cluster Of Chromosomal Microdeletions And The Deleted Genes' Functions, David Tilstra Md, Kevin Martens, Inge Heulens, Sandra Meulemans

Articles

Hypotonia-cystinuria syndrome (HCS) is a recessive disorder caused by microdeletions of SLC3A1 and PREPL on chromosome 2p21. Patients present with generalized hypotonia at birth, failure to thrive, growth retardation and cystinuria type I. While the initially described HCS families live in small regions in Belgium and France, we have now identified HCS alleles in patients and carriers from the Netherlands, Italy, Canada and United States of America. Surprisingly, among the nine deletions detected in those patients, only one novel deletion was found. Furthermore, one previously described deletion was found six times, another twice. Finally, we have investigated the frequency of …

Uniaxial Stretch-Induced Regulation Of Mitogen-Activated Protein Kinase, Akt And P70s6 Kinase In The Ageing Fischer 344 × Brown Norway Rat Aorta, Kevin M. Rice, Devashish H. Desai, Deborah L. Preston, Paulette S. Wehner, Eric R. Blough

MIIR Faculty Research

The effects of ageing on the cardiovascular system contribute to substantial alterations in cellular morphology and function. The variables regulating these changes are unknown; however, one set of signalling molecules that may be of particular importance in mediating numerous cellular responses, including control of cell growth, differentiation and adaptation, are the proteins associated with the mitogen-activated protein kinase (MAPK) signalling systems. The MAPKs, in conjunction with the p70 S6k signalling cascade, have emerged as critical components for regulating numerous mechanotransduction-related cellular responses. Here we investigate the ability of uniaxial stretch to activate the MAPK and p70 S6k pathways in adult …

Lean And Obese Zucker Rats Exhibit Different Patterns Of P70s6kinase Regulation In The Tibialis Anterior Muscle In Response To High Force Muscle Contraction, Anjaiah Katta

Theses, Dissertations and Capstones

Increased muscle loading results in phosphorylation of the 70 kDa ribosomal S6 kinase (p70s6k) signaling pathway and this event strongly correlates with degree of muscle adaptation following resistance exercise. Here, we compared the basal and contraction- induced phosphorylation of p70s6k, Akt and mTOR in tibialis anterior muscles of lean and obese Zucker rats. Immunoblotting demonstrated differences in level of basal p70S6k phosphorylation (Thr 389) in the normal and diabetic TA. HFES had an increase in p70S6k (Thr389) phosphorylation at 0-, 1- and 3-hr in lean TA and only at 3-hr in obese TA. mTOR (Ser 2448) Phosphorylation was elevated in …

Age-Related Dgc Structure And Function In The F344/N X Bn Rat Heart, Sunil K. Kakarla

Theses, Dissertations and Capstones

Recent data has suggested that disruption of the dystrophin-glycoprotein complex (DGC) may be involved in mediating the progression of cardiac hypertrophy and failure. Here we examined the regulation of DGC proteins in the hearts of adult (6 months), aged (30 months), and very aged (36 months) F344/N X BN rats . Compared to adult animals, the content of α- and β-dystroglycan were 6.93 ± 5.16% and 58.36 ± 3.64% higher, respectively (P < 0.05) in very aged animals. Immunoblotting and immunhistochemical analysis suggested that aging appeared to diminish alpha-sarcoglycan, beta-sarcoglycan and delta-sarcoglycan content by 13.89 ± 3.1%,15.8 ± 2.8% and 18.63 ± 3.04%, respectively (P < 0.05). These alterations in the DGC occurred coincident with age- associated alterations in cytoplasmic anti-rat IgG immunoreactivity, TUNEL positive nuclei, alpha-fodrin cleavage, indices of caspase-3 activation and diminished AKT phosphoryation (Ser 308). Taken together, these data suggest that aging alters cardiac DGC structure and function.

Age-Associated Changes In Hearts Of Male Fischer 344/Brown Norway F1 Rats, Ernest M. Walker Jr., Michael S. Nillas, Elsa I. Mangiarua, Sylvestre Cansino, Ryan G. Morrison, Romaine R. Perdue, William E. Triest, Gary L. Wright, Mark Studeny, Paulette Wehner, Kevin M. Rice, Eric R. Blough

MIIR Faculty Research

Aging is associated with left ventricular hypertrophy, dilatation, and fibrosis of the heart. The Fischer 344/Brown Norway F1 (F344/BNF1) rat is recommended for age-related studies by the National Institutes on Aging because this hybrid rat lives longer and has a lower rate of pathological conditions than inbred rats. However, little is known about age-associated changes in cardiac and aortic function and structure in this model. This study evaluated age-related cardiac changes in male F344/BNF1 rats using ECHO, gross, and microscopic examinations. Rats aged 6-, 30-, and 36-mo were anesthetized and two-dimensional ECHO measurements, two-dimensional guided M-mode, Doppler M-mode, and other …

Gene Expression In The Mouse Placenta: Developmental And Stress Responses, Ciprian P. Gheorghe

Loma Linda University Electronic Theses, Dissertations & Projects

Successful placental development is crucial for optimal growth, maturation, and survival of the embryo/fetus. Placental failure and placental pathology contributes to both morbidity and mortality of the fetus. We sought to understand normal placental development and also placental responses to stress using oligonucleotide microarray technology. To examine genetic aspects of normal placental development, we investigated gene expression patterns in the murine placenta at embryonic day 10.5 (E10.5), E12.5, E15.5, and E17.5. Hypoxia has been identified as a major stressor in placental and fetal development. In order to comprehend more completely hypoxic stress responses we sought to measure gene expression changes …