Digital Commons Network^™

Importance Of The Ebp (Endocarditis- And Biofilm-Associated Pilus) Locus In The Pathogenesis Of Enterococcus Faecalis Ascending Urinary Tract Infection, Kavindra V Singh, Sreedhar R Nallapareddy, Barbara E Murray

Faculty, Staff and Student Publications

BACKGROUND: We recently demonstrated that the ubiquitous Enterococcus faecalis ebp (endocarditis- and biofilm-associated pilus) operon is important for biofilm formation and experimental endocarditis. Here, we assess its role in murine urinary tract infection (UTI) by use of wild-type E. faecalis OG1RF and its nonpiliated, ebpA allelic replacement mutant (TX5475).

METHODS: OG1RF and TX5475 were administered transurethrally either at an ~1 : 1 ratio (competition assay) or individually (monoinfection). Kidney pairs and urinary bladders were cultured 48 h after infection. These strains were also tested in a peritonitis model.

RESULTS: No differences were observed in the peritonitis model. In mixed UTIs, …

Inhibition Of Enterococcus Faecium Adherence To Collagen By Antibodies Against High-Affinity Binding Subdomains Of Acm, Sreedhar R Nallapareddy, Jouko Sillanpää, Vannakambadi K Ganesh, Magnus Höök, Barbara E Murray

Faculty, Staff and Student Publications

Strains of Enterococcus faecium express a cell wall-anchored protein, Acm, which mediates adherence to collagen. Here, we (i) identify the minimal and high-affinity binding subsegments of Acm and (ii) show that anti-Acm immunoglobulin Gs (IgGs) purified against these subsegments reduced E. faecium TX2535 strain collagen adherence up to 73 and 50%, respectively, significantly more than the total IgGs against the full-length Acm A domain (28%) (P < 0.0001). Blocking Acm adherence with functional subsegment-specific antibodies raises the possibility of their use as therapeutic or prophylactic agents.

Acquisition Of A Natural Resistance Gene Renders A Clinical Strain Of Methicillin-Resistant Staphylococcus Aureus Resistant To The Synthetic Antibiotic Linezolid, Seok-Ming Toh, Liqun Xiong, Cesar A Arias, Maria V Villegas, Karen Lolans, John Quinn, Alexander S Mankin

Faculty, Staff and Student Publications

Linezolid, which targets the ribosome, is a new synthetic antibiotic that is used for treatment of infections caused by Gram-positive pathogens. Clinical resistance to linezolid, so far, has been developing only slowly and has involved exclusively target site mutations. We have discovered that linezolid resistance in a methicillin-resistant Staphylococcus aureus hospital strain from Colombia is determined by the presence of the cfr gene whose product, Cfr methyltransferase, modifies adenosine at position 2503 in 23S rRNA in the large ribosomal subunit. The molecular model of the linezolid-ribosome complex reveals localization of A2503 within the drug binding site. The natural function of …

Agrobacterium Para/Mind-Like Virc1 Spatially Coordinates Early Conjugative Dna Transfer Reactions, Krishnamohan Atmakuri, Eric Cascales, Oliver T Burton, Lois M Banta, Peter J Christie

Faculty, Staff and Student Publications

Agrobacterium tumefaciens translocates T-DNA through a polar VirB/D4 type IV secretion (T4S) system. VirC1, a factor required for efficient T-DNA transfer, bears a deviant Walker A and other sequence motifs characteristic of ParA and MinD ATPases. Here, we show that VirC1 promotes conjugative T-DNA transfer by stimulating generation of multiple copies per cell of the T-DNA substrate (T-complex) through pairwise interactions with the processing factors VirD2 relaxase, VirC2, and VirD1. VirC1 also associates with the polar membrane and recruits T-complexes to cell poles, the site of VirB/D4 T4S machine assembly. VirC1 Walker A mutations abrogate T-complex generation and polar recruitment, …

Dynamics Of A Minimal Model Of Interlocked Positive And Negative Feedback Loops Of Transcriptional Regulation By Camp-Response Element Binding Proteins, Hao Song, Paul Smolen, Evyatar Av-Ron, Douglas A Baxter, John H Byrne

Faculty, Staff and Student Publications

cAMP-response element binding (CREB) proteins are involved in transcriptional regulation in a number of cellular processes (e.g., neural plasticity and circadian rhythms). The CREB family contains activators and repressors that may interact through positive and negative feedback loops. These loops can be generated by auto- and cross-regulation of expression of CREB proteins, via CRE elements in or near their genes. Experiments suggest that such feedback loops may operate in several systems (e.g., Aplysia and rat). To understand the functional implications of such feedback loops, which are interlocked via cross-regulation of transcription, a minimal model with a positive and negative loop …

An Innovative Approach To Impacting Student Academic Achievement And Attitudes: Pilot Study Of The Heads Up Virtual Molecular Biology Lab, Melanie M. Mowry Mph, Ross Shegog Phd, Nathalie Sessions Bba, Nancy G. Murray Drph

Advances in Teaching and Learning Day Abstracts

Introduction: The Virtual Molecular Biology Lab is an innovative, computer-based educational program designed to teach advanced high school biology students how to create a transgenic mouse model in a simulated laboratory setting. It was created in an effort to combat the current decrease in adolescent enthusiasm for and academic achievement in science and science careers, especially in Hispanic students. Because studies have found that hands-on learning, particularly computer-based instruction, is effective in enhancing science achievement, the Virtual Lab is a potential tool for increasing the number of Hispanic students that choose to enter science fields. [See PDF for complete abstract]

Single-Stranded Dna-Binding Proteins Regulate The Abundance Of Lim Domain And Lim Domain-Binding Proteins, Zhixiong Xu, Xianzhang Meng, Ying Cai, Hong Liang, Lalitha Nagarajan, Stephen J Brandt

Faculty, Staff and Student Publications

The LIM domain-binding protein Ldb1 is an essential cofactor of LIM-homeodomain (LIM-HD) and LIM-only (LMO) proteins in development. The stoichiometry of Ldb1, LIM-HD, and LMO proteins is tightly controlled in the cell and is likely a critical determinant of their biological actions. Single-stranded DNA-binding proteins (SSBPs) were recently shown to interact with Ldb1 and are also important in developmental programs. We establish here that two mammalian SSBPs, SSBP2 and SSBP3, contribute to an erythroid DNA-binding complex that contains the transcription factors Tal1 and GATA-1, the LIM domain protein Lmo2, and Ldb1 and binds a bipartite E-box-GATA DNA sequence motif. In …

Gsbs News, Spring 2007, Graduate School Of Biomedical Sciences, University Of Texas Health Science Center At Houston/M.D. Anderson Cancer Center

GSBS News

No abstract provided.

Radiation Injury Is A Potentially Serious Complication To Fluoroscopically-Guided Complex Interventions, Lk Wagner

Faculty, Staff and Student Publications

Radiation-induced injury to skin is an infrequent but potentially serious complication to complex fluoroscopically-guided interventional procedures. Due to a lack of experience with such injuries, the medical community has found fluoroscopically-induced injuries difficult to diagnose. Injuries have occurred globally in many countries. Serious injuries most frequently occur on the back but have also occurred on the neck, buttocks and anterior of the chest. Severities of injuries range from skin rashes and epilation to necrosis of the skin and its underlying structures. This article reviews the characteristics of these injuries and some actions that can be taken to reduce their likelihood …

Crystal Structure Of The Anabaena Sensory Rhodopsin Transducer, Lutz Vogeley, Vishwa D Trivedi, Oleg A Sineshchekov, Elena N Spudich, John L Spudich, Hartmut Luecke

Faculty, Staff and Student Publications

We present crystal structures of the Anabaena sensory rhodopsin transducer (ASRT), a soluble cytoplasmic protein that interacts with the first structurally characterized eubacterial retinylidene photoreceptor Anabaena sensory rhodopsin (ASR). Four crystal structures of ASRT from three different spacegroups were obtained, in all of which ASRT is present as a planar (C4) tetramer, consistent with our characterization of ASRT as a tetramer in solution. The ASRT tetramer is tightly packed, with large interfaces where the well-structured beta-sandwich portion of the monomers provides the bulk of the tetramer-forming interactions, and forms a flat, stable surface on one side of the tetramer (the …

Laser-Induced Transient Grating Analysis Of Dynamics Of Interaction Between Sensory Rhodopsin Ii D75n And The Htrii Transducer, Keiichi Inoue, Jun Sasaki, John L Spudich, Masahide Terazima

Faculty, Staff and Student Publications

The interaction between sensory rhodopsin II (SRII) and its transducer HtrII was studied by the time-resolved laser-induced transient grating method using the D75N mutant of SRII, which exhibits minimal visible light absorption changes during its photocycle, but mediates normal phototaxis responses. Flash-induced transient absorption spectra of transducer-free D75N and D75N joined to 120 amino-acid residues of the N-terminal part of the SRII transducer protein HtrII (DeltaHtrII) showed only one spectrally distinct K-like intermediate in their photocycles, but the transient grating method resolved four intermediates (K(1)-K(4)) distinct in their volumes. D75N bound to HtrII exhibited one additional slower kinetic species, which …

A Pure Population Of Lung Alveolar Epithelial Type Ii Cells Derived From Human Embryonic Stem Cells, Dachun Wang, David L Haviland, Alan R Burns, Eva Zsigmond, Rick A Wetsel

Faculty, Staff and Student Publications

Alveolar epithelial type II (ATII) cells are small, cuboidal cells that constitute approximately 60% of the pulmonary alveolar epithelium. These cells are crucial for repair of the injured alveolus by differentiating into alveolar epithelial type I cells. ATII cells derived from human ES (hES) cells are a promising source of cells that could be used therapeutically to treat distal lung diseases. We have developed a reliable transfection and culture procedure, which facilitates, via genetic selection, the differentiation of hES cells into an essentially pure (>99%) population of ATII cells (hES-ATII). Purity, as well as biological features and morphological characteristics …

2007 State Of The Journals Report, Vol.20 (3) January - March 2007, Houston Academy Of Medicine-Texas Medical Center Library

Library Lines (1998-2009)

No abstract provided.

Expression Of The Neural Stem Cell Markers Ng2 And L1 In Human Angiomyolipoma: Are Angiomyolipomas Neoplasms Of Stem Cells?, So Dug Lim, William Stallcup, Benjamin Lefkove, Baskaran Govindarajan, Kit Sing Au, Hope Northrup, Deborah Lang, David E Fisher, Avani Patel, Mahul B Amin, Jack L Arbiser

Faculty, Staff and Student Publications

Angiomyolipomas are benign tumors of the kidney which express phenotypes of smooth muscle, fat, and melanocytes. These tumors appear with increased frequency in the autosomal dominant disorder tuberous sclerosis and are the leading cause of morbidity in adults with tuberous sclerosis. While benign, these tumors are capable of provoking life threatening hemorrhage and replacement of the kidney parenchyma, resulting in renal failure. The histogenesis of these tumors is currently unclear, although currently, we believe these tumors arise from "perivascular epithelioid cells" of which no normal counterpart has been convincingly demonstrated. Recently, stem cell precursors have been recognized that can give …

Aldosterone-Induced Sgk1 Relieves Dot1a-Af9-Mediated Transcriptional Repression Of Epithelial Na+ Channel Alpha, Wenzheng Zhang, Xuefeng Xia, Mary Rose Reisenauer, Timo Rieg, Florian Lang, Dietmar Kuhl, Volker Vallon, Bruce C Kone

Faculty, Staff and Student Publications

Aldosterone plays a major role in the regulation of salt balance and the pathophysiology of cardiovascular and renal diseases. Many aldosterone-regulated genes--including that encoding the epithelial Na+ channel (ENaC), a key arbiter of Na+ transport in the kidney and other epithelia--have been identified, but the mechanisms by which the hormone modifies chromatin structure and thus transcription remain unknown. We previously described the basal repression of ENaCalpha by a complex containing the histone H3 Lys79 methyltransferase disruptor of telomeric silencing alternative splice variant a (Dot1a) and the putative transcription factor ALL1-fused gene from chromosome 9 (Af9) as well as the release …

Functional Taxonomy Of Bacterial Hyperstructures, Vic Norris, Tanneke Den Blaauwen, Armelle Cabin-Flaman, Roy H Doi, Rasika Harshey, Laurent Janniere, Alfonso Jimenez-Sanchez, Ding Jun Jin, Petra Anne Levin, Eugenia Mileykovskaya, Abraham Minsky, Milton Saier, Kirsten Skarstad

Faculty, Staff and Student Publications

The levels of organization that exist in bacteria extend from macromolecules to populations. Evidence that there is also a level of organization intermediate between the macromolecule and the bacterial cell is accumulating. This is the level of hyperstructures. Here, we review a variety of spatially extended structures, complexes, and assemblies that might be termed hyperstructures. These include ribosomal or "nucleolar" hyperstructures; transertion hyperstructures; putative phosphotransferase system and glycolytic hyperstructures; chemosignaling and flagellar hyperstructures; DNA repair hyperstructures; cytoskeletal hyperstructures based on EF-Tu, FtsZ, and MreB; and cell cycle hyperstructures responsible for DNA replication, sequestration of newly replicated origins, segregation, compaction, and …

A Day In The Life Of Pubmed: Analysis Of A Typical Day's Query Log, Jorge R Herskovic, Len Y Tanaka, William Hersh, Elmer V Bernstam

Faculty, Staff and Student Publications

OBJECTIVE: To characterize PubMed usage over a typical day and compare it to previous studies of user behavior on Web search engines. DESIGN: We performed a lexical and semantic analysis of 2,689,166 queries issued on PubMed over 24 consecutive hours on a typical day. MEASUREMENTS: We measured the number of queries, number of distinct users, queries per user, terms per query, common terms, Boolean operator use, common phrases, result set size, MeSH categories, used semantic measurements to group queries into sessions, and studied the addition and removal of terms from consecutive queries to gauge search strategies. RESULTS: The size of …

K1 Protein Of Human Herpesvirus 8 Suppresses Lymphoma Cell Fas-Mediated Apoptosis, Suizhao Wang, Shu Wang, Hoyoung Maeng, Daniel P Young, Om Prakash, Luis E Fayad, Anas Younes, Felipe Samaniego

Faculty, Staff and Student Publications

Expression of the K1 gene of human herpesvirus 8 activates nuclear factor-kappaB and induces lymph node hyperplasia and lymphomas in transgenic mice. To further delineate its role in cell survival, we determined whether K1 altered apoptosis of lymphoma cells. K1 protein is expressed in Kaposi sarcoma and primary effusion lymphoma. We retrovirally transfected BJAB lymphoma, THP-1, U937, and Kaposi sarcoma SLK cells to express K1 and a K1 mutant with the deleted immunoreceptor tyrosine-based activation motif (K1m). We challenged cells with an agonistic anti-Fas antibody, Fas ligand, irradiation, and tumor necrosis factor-related apoptosis-inducing ligand. K1 transfectants but not K1m transfectants …

Insider Express, Houston Academy Of Medicine-Texas Medical Center Library

Insider Express (2003-2013)

No abstract provided.

Vancomycin-Resistant Enterococcus Faecalis Endocarditis: Linezolid Failure And Strain Characterization Of Virulence Factors, Constantine Tsigrelis, Kavindra V Singh, Thais D Coutinho, Barbara E Murray, Larry M Baddour

Faculty, Staff and Student Publications

Infective endocarditis due to vancomycin-resistant (VR) Enterococcus faecalis has only rarely been reported. We report a case of VR E. faecalis endocarditis that failed to respond to linezolid therapy, outline the virulence traits of the isolate, and review previously published cases of VR E. faecalis endocarditis.

Nmr Structure Of A Complex Between The Virb9/Virb7 Interaction Domains Of The Pkm101 Type Iv Secretion System, Richard Bayliss, Richard Harris, Loic Coutte, Amy Monier, Remi Fronzes, Peter J Christie, Paul C Driscoll, Gabriel Waksman

Faculty, Staff and Student Publications

Type IV secretion (T4S) systems translocate DNA and protein effectors through the double membrane of Gram-negative bacteria. The paradigmatic T4S system in Agrobacterium tumefaciens is assembled from 11 VirB subunits and VirD4. Two subunits, VirB9 and VirB7, form an important stabilizing complex in the outer membrane. We describe here the NMR structure of a complex between the C-terminal domain of the VirB9 homolog TraO (TraO(CT)), bound to VirB7-like TraN from plasmid pKM101. TraO(CT) forms a beta-sandwich around which TraN winds. Structure-based mutations in VirB7 and VirB9 of A. tumefaciens show that the heterodimer interface is conserved. Opposite this interface, the …

Phosphorylation Of The Proline-Rich Domain Of Xp95 Modulates Xp95 Interaction With Partner Proteins, Robert E Dejournett, Ryuji Kobayashi, Shujuan Pan, Chuanfen Wu, Laurence D Etkin, Richard B Clark, Oliver Bögler, Jian Kuang

Faculty, Staff and Student Publications

The mammalian adaptor protein Alix [ALG-2 (apoptosis-linked-gene-2 product)-interacting protein X] belongs to a conserved family of proteins that have in common an N-terminal Bro1 domain and a C-terminal PRD (proline-rich domain), both of which mediate partner protein interactions. Following our previous finding that Xp95, the Xenopus orthologue of Alix, undergoes a phosphorylation-dependent gel mobility shift during progesteroneinduced oocyte meiotic maturation, we explored potential regulation of Xp95/Alix by protein phosphorylation in hormone-induced cell cycle re-entry or M-phase induction. By MALDI-TOF (matrix-assisted laser-desorption ionization-time-of-flight) MS analyses and gel mobility-shift assays, Xp95 is phosphorylated at multiple sites within the N-terminal half of the …

Phosphorylation Of The Proline-Rich Domain Of Xp95 Modulates Xp95 Interaction With Partner Proteins, Robert E Dejournett, Ryuji Kobayashi, Shujuan Pan, Chuanfen Wu, Laurence D Etkin, Richard B Clark, Oliver Bögler, Jian Kuang

Faculty, Staff and Student Publications

The mammalian adaptor protein Alix [ALG-2 (apoptosis-linked-gene-2 product)-interacting protein X] belongs to a conserved family of proteins that have in common an N-terminal Bro1 domain and a C-terminal PRD (proline-rich domain), both of which mediate partner protein interactions. Following our previous finding that Xp95, the Xenopus orthologue of Alix, undergoes a phosphorylation-dependent gel mobility shift during progesteroneinduced oocyte meiotic maturation, we explored potential regulation of Xp95/Alix by protein phosphorylation in hormone-induced cell cycle re-entry or M-phase induction. By MALDI-TOF (matrix-assisted laser-desorption ionization-time-of-flight) MS analyses and gel mobility-shift assays, Xp95 is phosphorylated at multiple sites within the N-terminal half of the …

Caring Minds, University Of Texas Health Science Center At Houston School Of Nursing

Caring Minds

• Greetings from Dean Patricia Starck
• New DNP program explores new frontiers of nursing
• Profile Joanne V. Hickey, PhD, APRN, BC, ACNP, FAAN, FCCM
• With assistance from PARTNERS scholarship, Family Practice Nurse pursues her dream through new DNP program
• School of Nursing offers training in geriatrics for nurses
• PARTNERS organization endows first professorship
• University of Texas Health Services planning to expand number of clinics
• Caring Leaders
• The Engine of Innovation: School of Nursing researchers part of $36 million NIH grant to spur innovation
• Johnson and Johnson gala spotlights nurses Chad and Heath LePray
• UT School of Nursing and Memorial Hermann Hospital …

Relationships, Income Support And Decision Making: A Qualitative Synopsis, Angie Logan, Kevin Meir

Journal of Family Strengths

This qualitative study of one midwestern state’s child protective services addresses whether an income support measure for poor biological caregivers reduces the length of time that their children spend in foster care. The overall findings suggest that workers do value the worker-family relationship. However, some view the immediate worker-client relationship as secondary to the inclusion of extended familial supports particularly as related to sustained more long-term outcome achievement. Most workers additionally agree that client involvement during all phases of the reunification process is critical.

Learning What Works: Demonstrating Practice Effectiveness With Children And Families Through Retrospective Investigation, Daria V. Hanssen, Irwin Epstein

Journal of Family Strengths

Intensive family preservation services (IFPS), designed to stabilize at-risk families and avert out-of-home care, have been the focus of many randomized, experimental studies. Employing a retrospective “clinical data-mining” (CDM) methodology (Epstein, 2001), this study makes use of available information extracted from client records in one IFPS agency over the course of two years. The primary goal of this descriptive and associational study was to gain a clearer understanding of IFPS service delivery and effectiveness. Interventions provided to families are delineated and assessed for their impact on improved family functioning, their impact on the reduction of family violence, as well as …

A Model Of Late Long-Term Potentiation Simulates Aspects Of Memory Maintenance, Paul Smolen

Faculty, Staff and Student Publications

Late long-term potentiation (L-LTP) denotes long-lasting strengthening of synapses between neurons. L-LTP appears essential for the formation of long-term memory, with memories at least partly encoded by patterns of strengthened synapses. How memories are preserved for months or years, despite molecular turnover, is not well understood. Ongoing recurrent neuronal activity, during memory recall or during sleep, has been hypothesized to preferentially potentiate strong synapses, preserving memories. This hypothesis has not been evaluated in the context of a mathematical model representing ongoing activity and biochemical pathways important for L-LTP. In this study, ongoing activity was incorporated into two such models - …

Family Preservation: The Parents’ Perceptions, Cheryl D. Lee, Cecilia Ayon

Journal of Family Strengths

This research documents the perspective of 100 parents who had an open case with the Department of Children and Family Service’s (DCFS) regarding their family’s well-being, reasons for referral and satisfaction with services. Two DCFS services, Family Preservation (FP) and routine Family Maintenance (FM) were examined using standardized instruments. Parents’ responses regarding reasons for involvement with the system differed from DCFS administrative data. FP parents had more children, were more likely to be monolingual Spanish speakers, and perceived greater improvement in discipline and emotional care of children and housing than FM parents. FP parents reported being satisfied with services. Implications …

Towards A Hybrid Method To Categorize Interruptions And Activities In Healthcare, Juliana J. Brixey, David J. Robinson, Craig W. Johnson, Todd R. Johnson, James P. Turley, Vimla L. Patel, Jiajie Zhang

Faculty, Staff and Student Publications

ObjectiveInterruptions are known to have a negative impact on activity performance. Understanding how an interruption contributes to human error is limited because there is not a standard method for analyzing and classifying interruptions. Qualitative data are typically analyzed by either a deductive or an inductive method. Both methods have limitations. In this paper a hybrid method was developed that integrates deductive and inductive methods for the categorization of activities and interruptions recorded during an ethnographic study of physicians and registered nurses in a Level One Trauma Center. Understanding the effects of interruptions is important for designing and evaluating informatics …

Repression Of Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand (Trail) But Not Its Receptors During Oral Cancer Progression, Nadarajah Vigneswaran, Darryl C. Baucum, Jean Wu, Yahuan Lou, Jerry Bouquot, Susan Muller, Wolfgang Zacharias

Faculty, Staff and Student Publications

BACKGROUND: TRAIL plays an important role in host immunosurveillance against tumor progression, as it induces apoptosis of tumor cells but not normal cells, and thus has great therapeutic potential for cancer treatment. TRAIL binds to two cell-death-inducing (DR4 and DR5) and two decoy (DcR1, and DcR2) receptors. Here, we compare the expression levels of TRAIL and its receptors in normal oral mucosa (NOM), oral premalignancies (OPM), and primary and metastatic oral squamous cell carcinomas (OSCC) in order to characterize the changes in their expression patterns during OSCC initiation and progression. METHODS: DNA microarray, immunoblotting and immunohistochemical analyses were used to …