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Articles 91 - 112 of 112
Full-Text Articles in Cell Biology
Optimization Of Labeling Techniques; Determination Of Best Parameter For Olfactory Mucosal Progenitor Cell Delivery And Study Of Effects Of Methylene Blue And Polyethylene Glycol In An Animal Model Of Spinal Cord Injury, Kiran Kumar Rokkappanavar
Optimization Of Labeling Techniques; Determination Of Best Parameter For Olfactory Mucosal Progenitor Cell Delivery And Study Of Effects Of Methylene Blue And Polyethylene Glycol In An Animal Model Of Spinal Cord Injury, Kiran Kumar Rokkappanavar
Wayne State University Theses
In the United States, the incidence of TSCI is about 40 per million persons per year, with approximately 250,000 living survivors of TSCI in the United States in July 2005. A number of human clinical trials (85) are ongoing using stem cells to evaluate the methods to reduce the injury following TBI. Among the stem cells, olfactory mucosal progenitor cells have several advantages with respect to ease of obtaining, fate of cells, etc. Our study was intended to optimize the labeling technique and to determine the best parameter to deliver the stem cells to the site of injury. We found …
Regulation Of Nuclear Localization Of The Sole Sumo-Conjugating Enzyme, Ubc9, Palak Sekhri
Regulation Of Nuclear Localization Of The Sole Sumo-Conjugating Enzyme, Ubc9, Palak Sekhri
Wayne State University Theses
The covalent and reversible conjugation of small ubiquitin-like modifier (SUMO) proteins to hundreds of different cellular proteins is catalyzed by a cascade of enzymes including an E1-activating enzyme (SAE1/SAE2), an E2-conjugating enzyme (Ubc9) and multiple E3 ligases. As the only E2 enzyme for SUMO-conjugation, Ubc9 localizes mainly in the nucleus and plays an essential role in regulation of many cellular processes including cell cycle progression through mitosis, cell migration, genome stability, stress response, transcription, and nuclear transport in eukaryotic cells. It is hypothesized that the nuclear localization of Ubc9 is required for efficient sumoylation inside the nucleus because both the …
Novel Copper (Ii) Mediated Transfection Nano-Systems And Biological Properties Of Pyridinium Surfactants, Sarit Pal
Open Access Theses & Dissertations
Efficacy of gene therapy is relied upon the improvement of gene delivery vectors into mammalian cells. Although viral-based polynucleotide carriers are still considered as the most common method for gene delivery but the cost effectiveness, nonspecific lethal immune response has evoked the renaissance of non-viral synthetic delivery systems. An initial discovery by Felgnar et al showed Cationic Liposomes (CLs) (having an overall positive charge) when mixed with DNA to form CL-DNA complexes can enhance the transfer of polynucleotides into cells followed by its expression. Presently, a flurry of experimental works is taking place for the better understanding of structural characterization …
A Novel Fkbp52/Β-Catenin Complex Specifically Regulates Androgen Receptor Activity, Cheryl Lynne Storer
A Novel Fkbp52/Β-Catenin Complex Specifically Regulates Androgen Receptor Activity, Cheryl Lynne Storer
Open Access Theses & Dissertations
The androgen receptor complex plays an essential role in prostate cancer progression due to exploitation of the androgen receptor (AR) as a transcription factor. The final stage of the receptor complex consists of a dimerized receptor, a dimeric heat shock protein (Hsp90), the cochaperone p23, and an immunophilin. Hormone-dependent prostate cancer progresses due to key interactions between the androgen receptor complex and its ligand α dihydrotestosterone (DHT). While current treatments focus on blocking the androgen receptor-ligand interactions, these therapies are no longer effective in advanced stage, hormone-refractory prostate cancer (HRPC).
Therefore, we have been interested in targeting other members of …
Attachment Ability And Melanoma Inhibitory Activity Mrna Expression Level Changes In Murine B16-F10 Melanoma Cells Post Nanosecond Electric Pulses, Hongxia Jia
Theses and Dissertations in Biomedical Sciences
The effects of high-voltage nanosecond electric pulses (nsEPs) on metastatic melanoma are still unclear. Hence, we applied one, two, three, and four 300 ns 40 kV/cm pulses to murine B16-F10 melanoma cells. Cell attachment ability was determined by comparing the number of floating cells and the percentage of attached cells. Melanoma inhibitory activity (MIA) is a secretory protein that is highly correlated with the malignancy and metastasis of malignant melanomas. We used MIA as our target to evaluate the effect of nsEPs on metastasis. Pulsed (experimental) and unpulsed (control) cells were incubated at 37°C under a 5% CO2 atmosphere. …
Acidic Pericellular Ph: Effects On Proteolysis And Gene Expression As Determined In 3d Models Of Breast Carcinoma, Jennifer M. Rothberg
Acidic Pericellular Ph: Effects On Proteolysis And Gene Expression As Determined In 3d Models Of Breast Carcinoma, Jennifer M. Rothberg
Wayne State University Dissertations
Among the non-cellular microenvironmental factors that contribute to malignancy of solid tumors is an acidic peritumoral pH. The first objective was to determine if an acidic extracellular pH observed in vivo (i.e., pHe 6.8) affects the activity of proteases, such as cathepsin B, that contribute to degradation of collagen IV by tumor cells when grown in biologically relevant three-dimensional cultures. At pHe 6.8 there were increases in pericellular active cysteine cathepsins and in degradation of DQ-collagen IV, which was partially blocked by a cathepsin B inhibitor. Imaging probes for active cysteine cathepsins localized to tumors in vivo. The amount of …
The Transcriptional Regulation Of Flagellin-Induced Innate Protection Of The Cornea: Role Of Irf1 And Atf3, Gi Sang Yoon
The Transcriptional Regulation Of Flagellin-Induced Innate Protection Of The Cornea: Role Of Irf1 And Atf3, Gi Sang Yoon
Wayne State University Dissertations
Pre-exposure of the cornea to TLR5 ligand flagellin induces profound mucosal innate protection against infections by reprogramming gene expression. This study explored the flagellin-induced modifications of transcription factor expression and function, specifically of IRF1 and ATF3 in corneal epithelial cells to elucidate the transcriptional mechanisms underlying the protective function of flagellin on the cornea.
Initially we used Superarray to screen for transcription factors and identified Interferon Regulatory Factor (IRF) 1 and Activating Transcription Factor (ATF) 3 as the most drastically affected genes by flagellin pretreatment in P. aeruginosa challenged human corneal epithelial cells (CEC). However, flagellin pretreatment had opposite effects …
Interaction Between Centromeric Histone H3 Variant And Shugoshin, Visarut Buranasudja
Interaction Between Centromeric Histone H3 Variant And Shugoshin, Visarut Buranasudja
Open Access Theses
Precise and faithful segregation of chromosome segregation during mitosis depends on the ability of the cell to regulate chromosome bi-orientation on the mitotic spindle. Shugoshin (Sgo1), the protector of meiotic centromeric cohesin, is required for proper establishment of chromosome bi-orientation. Sgo1 plays a crucial role as part of a mitotic tension sensor between sister chromatids. Recently, Sgo1 has been reported to interact with histone H3 at the pericentromere region, as an important factor for tension sensing and chromosome segregation. However, the role of Sgo1 in tension sensing at centromere is still elusive. The centromere is the region of attachment of …
Modulation Of Cell-Matrix Interaction For Cryopreservation Of Engineered Tissue, Angela Christine Seawright
Modulation Of Cell-Matrix Interaction For Cryopreservation Of Engineered Tissue, Angela Christine Seawright
Open Access Theses
Long term preservation of functional engineered tissues can significantly advance tissue engineering industry and regenerative medicine. Several preservation techniques have been proposed and investigated for this purpose, and cryopreservation is a leading candidate. While tissues are cryopreserved, ice forms in both the extracellular and intracellular spaces and causes freezing-induced spatiotemporal deformation of the tissue. During this process the cells undergo dehydration by the freezing-induced osmotic pressure difference and mechanical deformation, transmitted through cell-extracellular matrix adhesions. However, the significance and interaction of these cellular level transport and mechanics processes are not well understood. Therefore, this study aims to establish mechanistic understanding …
Menthol Binding And Inhibition Of A7-Nicotinic Acetylcholine Receptors, Abrar Ashoor, Jacob C. Nordman, Daniel Veltri, Keun-Hang Susan Yang, Lina T. Al Kury, Yaroslav M. Shuba, Mohamed Magoub, Frank Christopher Howarth, Bassem Sadek, Amarda Shehu, Nadine Kabbani, Murat Oz
Menthol Binding And Inhibition Of A7-Nicotinic Acetylcholine Receptors, Abrar Ashoor, Jacob C. Nordman, Daniel Veltri, Keun-Hang Susan Yang, Lina T. Al Kury, Yaroslav M. Shuba, Mohamed Magoub, Frank Christopher Howarth, Bassem Sadek, Amarda Shehu, Nadine Kabbani, Murat Oz
Mathematics, Physics, and Computer Science Faculty Articles and Research
Menthol is a common compound in pharmaceutical and commercial products and a popular additive to cigarettes. The molecular targets of menthol remain poorly defined. In this study we show an effect of menthol on the α7 subunit of the nicotinic acetylcholine (nACh) receptor function. Using a two-electrode voltage-clamp technique, menthol was found to reversibly inhibit α7-nACh receptors heterologously expressed in Xenopus oocytes. Inhibition by menthol was not dependent on the membrane potential and did not involve endogenous Ca2+-dependent Cl− channels, since menthol inhibition remained unchanged by intracellular injection of the Ca2+ chelator BAPTA and perfusion with Ca2+-free bathing solution containing …
Differential Modulation Of Functional Dynamics And Allosteric Interactions In The Hsp90-Cochaperone Complexes With P23 And Aha1: A Computational Study, Kristin Blacklock, Gennady M. Verkhivker
Differential Modulation Of Functional Dynamics And Allosteric Interactions In The Hsp90-Cochaperone Complexes With P23 And Aha1: A Computational Study, Kristin Blacklock, Gennady M. Verkhivker
Mathematics, Physics, and Computer Science Faculty Articles and Research
Allosteric interactions of the molecular chaperone Hsp90 with a large cohort of cochaperones and client proteins allow for molecular communication and event coupling in signal transduction networks. The integration of cochaperones into the Hsp90 system is driven by the regulatory mechanisms that modulate the progression of the ATPase cycle and control the recruitment of the Hsp90 clientele. In this work, we report the results of computational modeling of allosteric regulation in the Hsp90 complexes with the cochaperones p23 and Aha1. By integrating protein docking, biophysical simulations, modeling of allosteric communications, protein structure network analysis and the energy landscape theory we …
Characterization Of G-Patch Motif Contribution To Prp43 Function In The Pre-Messenger Rna Splicing And Ribosomal Rna Biogenesis Pathways, Daipayan Banerjee
Characterization Of G-Patch Motif Contribution To Prp43 Function In The Pre-Messenger Rna Splicing And Ribosomal Rna Biogenesis Pathways, Daipayan Banerjee
Theses and Dissertations--Biology
The DExD/H-box protein Prp43 is essential for two biological processes: nucleoplasmic pre-mRNA splicing and nucleolar rRNA maturation. The biological basis for the temporal and spatial regulation of Prp43 remains elusive. The Spp382/Ntr1, Sqs1/Pfa1 and Pxr1/Gno1 G-patch proteins bind to and activate the Prp43 DExD/H box-helicase in pre-mRNA splicing (Spp382) and rRNA processing (Sqs1, Pxr1). These Prp43-interacting proteins each contain the G-patch domain, a conserved sequence of ~48 amino acids that includes 6 highly conserved glycine (G) residues. Five annotated G-patch proteins in baker’s yeast (i.e., Spp382, Pxr1, Spp2, Sqs1 and Ylr271) and with the possible exception of the uncharacterized Ylr271 …
Molecular Mechanisms Involved In Anhydrobiosis Of Insect Cells, Diyagama Arachchi Ralalage Dilini Sewwandi Samarajeewa
Molecular Mechanisms Involved In Anhydrobiosis Of Insect Cells, Diyagama Arachchi Ralalage Dilini Sewwandi Samarajeewa
Masters Theses
Animals possessing tolerance to extreme water stress are termed anhydrobiotes. Many desiccation tolerant organisms respond to water stress by intracellular accumulation of selected sugars such as trehalose and larger macromolecules such as Late Embryogenesis Abundant (LEA) proteins and thereby maintain the cell viability. Evidence indicates that the presence of trehalose and Late Embryogenesis Abundant (LEA) proteins may work synergistically to confer cellular protection during drying in eukaryotic cells. We evaluated any increase in cellular desiccation tolerance by expressing different LEA proteins in a non-desiccation tolerant insect cell line Drosophila melanogaster (fruit fly) (Kc167 cells) in the presence of trehalose.
Transgenic …
Late Developing Mammary Tumors And Hyperplasia Induced By A Low-Oncogenic Variant Of Mouse Mammary Tumor Virus (Mmtv) Express Genes Identical To Those Induced By Canonical Mmtv, Robert D. Bruno
School of Medical Diagnostics & Translational Sciences Publications
Background: The canonical milk-transmitted mouse mammary tumor virus (MMTV) of C3H mice (C3H-MMTV) rapidly induces tumors in 90% of infected animals by 8 months of age. Pro-viral insertions of C3H-MMTV into genomic DNA results in the overexpression of common core insertion site (CIS) genes, including Wnt1/10b, Rspo2, and Fgf3. Conversely, infection by either the endogenous Mtv-1 virus (in C3Hf) or the exogenous nodule-inducing virus (NIV) (in Balb/c NIV) induces premalignant mammary lesions and tumors with reduced incidence and longer latency than C3H-MMTV. Here, we asked whether Mtv-1/NIV affected the expression of core CIS genes.
Findings: We confirmed the presence of …
The Bio-Nano-Interface In Predicting Nanoparticle Fate And Behaviour In Living Organisms: Towards Grouping And Categorising Nanomaterials And Ensuring Nanosafety By Design, Hugh Byrne, Arti Ahluwalia, Diana Boraschi,, Bengt Fadeel, Peter Gehr, Arno C. Gutleb, Michaela Kendall, Manthos Papadopoulos, Iseult Lynch
The Bio-Nano-Interface In Predicting Nanoparticle Fate And Behaviour In Living Organisms: Towards Grouping And Categorising Nanomaterials And Ensuring Nanosafety By Design, Hugh Byrne, Arti Ahluwalia, Diana Boraschi,, Bengt Fadeel, Peter Gehr, Arno C. Gutleb, Michaela Kendall, Manthos Papadopoulos, Iseult Lynch
Articles
In biological media, nanoparticles acquire a coating of biomolecules (proteins, lipids, polysaccharides) from their surroundings, which reduces their surface energy and confers a biological identity to the particles. This adsorbed layer is the interface between the nanomaterial and living systems and therefore plays a significant role in determining the fate and behaviour of the nanoparticles. This review summarises the state of the art in terms of understanding the bio-nano interface and provides direction for potential future research directions and some recommendations for future priorities and strategies to support the safe implementation of nanotechnologies. The central premise is that nanomaterials must …
Functional And Mutational Analysis Of Human Recq-Like Dna Helicases In Saccharomyces Cerevisiae, Hamed Mirzaei-Souderjani
Functional And Mutational Analysis Of Human Recq-Like Dna Helicases In Saccharomyces Cerevisiae, Hamed Mirzaei-Souderjani
USF Tampa Graduate Theses and Dissertations
RecQ-like proteins are a family of DNA helicases that are evolutionary conserved from prokaryotes to eukaryotes. A large amount of experimental evidence suggests these proteins have a major role in the maintenance of genome stability. In humans five RecQ like helicase have been identified (RecQL1, BLM, WRN, RecQL4, and RecQL5), three of which are associated with rare genetic disorders with sever chromosomal and developmental abnormalities, and an elevated predisposition to cancer. Among the disease associated RecQ-like helicases, BLM and WRN have been subject to extensive research, while our collective knowledge about the function of RecQL4 is still very limited. Similarly, …
Sirt1 Regulation Of The Heat Shock Response In An Hsf1-Dependent Manner And The Impact Of Caloric Restriction, Rachel Rene Raynes
Sirt1 Regulation Of The Heat Shock Response In An Hsf1-Dependent Manner And The Impact Of Caloric Restriction, Rachel Rene Raynes
USF Tampa Graduate Theses and Dissertations
The heat shock response (HSR) is the cell's molecular reaction to protein damaging stress and is critical in the management of denatured proteins. Activation of HSF1, the master transcriptional regulator of the HSR, results in the induction of molecular chaperones called heat shock proteins (HSPs). Transcription of hsp genes is promoted by the hyperphosphorylation of HSF1, while the attenuation of the HSR is regulated by a dual mechanism involving negative feedback inhibition from HSPs and acetylation at a critical lysine residue within the DNA binding domain of HSF1, which results in a loss of affinity for DNA. SIRT1 is a …
Regulation Of The Tumor Suppresser P53 And Survivin By Ras And Ral Gtpases:Implications For Malignant Transformation, Awet G. Tecleab
Regulation Of The Tumor Suppresser P53 And Survivin By Ras And Ral Gtpases:Implications For Malignant Transformation, Awet G. Tecleab
USF Tampa Graduate Theses and Dissertations
Abstract
Although the critical role of the small GTPases Ras and Ral in oncogenesis has been well documented, much remains to be investigated about the molecular mechanism by which these GTPases regulate malignant transformation. The work under this thesis made two major contributions to this field. The first is the discovery that K-Ras, RalA and/or RalB are required for the maintenance of the high levels of the anti-apoptotic protein survivin in some human cancer cells, and the second is the demonstration that down regulation of K-Ras, RalA and/or RalB, but not Raf-1 or Akt1/2, stabilizes the tumor suppressor p53 and …
Epigenetic Modifiers To Augment The Immunogenicity Of Chronic Lymphocytic Leukemia, Jason A. Dubovsky
Epigenetic Modifiers To Augment The Immunogenicity Of Chronic Lymphocytic Leukemia, Jason A. Dubovsky
USF Tampa Graduate Theses and Dissertations
Cancer cells employ a litany of immunosuppressive and immunevasive strategies to avoid detection and elimination by the various arms of the innate and adaptive immune system. Many hematologic and solid tumors progressively develop a specialized microenvironment which promotes tissue restructuring inflammation while masking the immune signature of the tumor cells themselves. Chronic lymphocytic leukemia, a malignancy of mature B lymphocytes must constantly balance on the precipice of immune recognition. A mature antigen presenting cell themselves, CLL clonal growth is dependent on the very interactions which, if effective, could potentially lead to their demise. To circumvent this, CLL clones set up …
Phosphorylation Of Histone Deacetylase 6 Within Its C-Terminal Region By Extracellular Signal Regulated Kinase 1, Kendra Allana Williams
Phosphorylation Of Histone Deacetylase 6 Within Its C-Terminal Region By Extracellular Signal Regulated Kinase 1, Kendra Allana Williams
USF Tampa Graduate Theses and Dissertations
http://upload.etdadmin.com/etdadmin/pdfout/222759_supp_undefined_2A63E500-E9D7-11E2-925E-BE522E1BA5B1.PDF
Drug Resistance Mechanisms To Gamma-Secretase Inhibitors In Human Colon Cancer Cells, Cindy R. Timme
Drug Resistance Mechanisms To Gamma-Secretase Inhibitors In Human Colon Cancer Cells, Cindy R. Timme
USF Tampa Graduate Theses and Dissertations
Colorectal cancer is the third leading cause of cancer-related mortality. Much progress has been achieved in combating this disease with surgical resection and chemotherapy in combination with targeted drugs. However, most metastatic patients develop drug resistance so new modalities of treatment are needed.
Notch signaling plays a vital role in intestinal homeostasis, self-renewal, and cell fate decisions during post-development and is activated in colorectal adenocarcinomas. Under debate is its role in carcinomas and metastatic disease. In theory, blocking Notch activation using gamma-secretase inhibitors (GSIs) may show efficacy alone or in combination with chemotherapy in the treatment of colon cancer.
In …
Toc Complex Formation: An Investigation Of The Interactions Governing Toc Complex Composition And Assembly, Steven R. Siman
Toc Complex Formation: An Investigation Of The Interactions Governing Toc Complex Composition And Assembly, Steven R. Siman
Theses and Dissertations (Comprehensive)
Chloroplast-destined preproteins are translated in the cytosol, and posttranslationally targeted to and translocated across the double envelope membrane of the chloroplast by the coordinated activities of two translocon complexes: the Translocons at the Outer and Inner envelope membrane of the Chloroplast (TOC and TIC, respectively). In the model organism Arabidopsis thaliana the core TOC components include two families of GTPase receptors: TOC159 (atToc159, -132, and -120) and TOC34 (atToc33 and -34). These receptor families are hypothesized to assemble into distinct complexes and recognize transit peptides present on the N-terminus of chloroplast-destined preproteins. The GTPase domains of the TOC159 and TOC34 …