Medicine and Health Sciences Commons^™

Detection Methods And Intestinal Adherence Of Non-O157 Shiga Toxin-Producing Escherichia Coli, Zachary R. Stromberg

School of Veterinary and Biomedical Sciences: Dissertations, Theses, and Student Research

Shiga toxin-producing Escherichia coli (STEC) are enteric pathogens of humans. Cattle serve as a reservoir and harbor STEC in their intestines. Intimin-positive STEC are referred to as enterohemorrhagic E.coli (EHEC). Seven serogroups (O26, O45, O103, O111, O121, O145, and O157) account for the majority of illness due to STEC and are hereafter referred to as STEC/EHEC-7. To improve detection, enrichment broths were compared for supporting growth of STEC-7 and STEC O104:H4 (STEC-8). In pure culture, STEC enriched in trypticase soy broth (TSB) had significantly greater growth compared to TSB containing antimicrobials. In fecal samples, E. coli broth enrichment yielded growth …

Genestation 1.0: A Synthetic Resource Of Diverse Evolutionary And Functional Genomic Data For Studying The Evolution Of Pregnancy-Associated Tissues And Phenotypes, Mara Kim, Brian A. Cooper, Rohit Venkat, Julie B. Phillips, Haley R. Eidem, Jibril Hirbo, Sashank Nutakki, Scott M. Williams, Louis J. Muglia, J. Anthony Capra, Kenneth Petren, Patrick Abbot, Antonis Rokas, Kriston L. Mcgary

Dartmouth Scholarship

Mammalian gestation and pregnancy are fast evolving processes that involve the interaction of the fetal, maternal and paternal genomes. Version 1.0 of the GEneSTATION database (http://genestation.org) integrates diverse types of omics data across mammals to advance understanding of the genetic basis of gestation and pregnancy-associated phenotypes and to accelerate the translation of discoveries from model organisms to humans. GEneSTATION is built using tools from the Generic Model Organism Database project, including the biology-aware database CHADO, new tools for rapid data integration, and algorithms that streamline synthesis and user access. GEneSTATION contains curated life history information on pregnancy and …

Exogenous Administration Of Lipids To Steers Alters Aspects Of The Innate Immune Response To Endotoxin Challenge, Nicole C. Burdick Sanchez, Jeffery A. Carroll, Janet R. Donaldson, Joe O. Buntyn, Ty B. Schmidt

Department of Animal Science: Faculty Publications

This study examined the effects of increasing energy availability from both dextrose and lipid treatments on the proinflammatory response to LPS in Holstein steers. Steers were randomly assigned to one of three groups: saline at 0.5 ml/ kg body weight (Control) or 50% dextrose [0.5 ml/kg body weight (Dextrose) to mimic calm cattle’s response to LPS] administered immediately prior to LPS (0.5 mg/kg body weight at 0 h) or continuous lipid emulsion infusion from –1 to 6 h [Intralipid 20% (Baxter, Deerfield, IL USA); 0.5 ml/kg/hr (Lipid) to mimic temperamental cattle]. Concentrations of non-esterified fatty acids (NEFA) were greater in …

Structured Light Scatteroscopy, Venkataramanan Krishnaswamy, Jonathan T. Elliott, David M. Mcclatchy, Richard J. Barth Jr., Wendy A. Wells, Brian W. Pogue, Keith D. Paulsen

Dartmouth Scholarship

A new imaging approach, structured light scatteroscopy (SLS), is demonstrated, which offers rapid wide-field imaging of microscopic morphological variations in bulk tissue surfaces. Elastic scattering of light offers exquisite sensitivity to ultrastructural changes at multiple size scales ranging from nanometers to millimeters, but in bulk tissues the confounding effects of molecular absorption and strong multiple scattering of light often lead to a dramatic reduction in scatter contrast and specificity. It is demonstrated that the SLS using structured high spatial frequency illumination and detection to probe the tissue achieves direct, absorption-independent, high-resolution maps of the scattering response. The scattering response is …

Host Species Restriction Of Middle East Respiratory Syndrome Coronavirus Through Its Receptor, Dipeptidyl Peptidase 4, Neeltje Van Doremalen, Kerri L. Miazgowicz, Shauna Milne-Price, Trenton Bushmaker, Shelly Robertson, Dana Scott, Joerg Kinne, Jason S. Mclellan

Dartmouth Scholarship

Middle East respiratory syndrome coronavirus (MERS-CoV) emerged in 2012. Recently, the MERS-CoV receptor dipeptidyl peptidase 4 (DPP4) was identified and the specific interaction of the receptor-binding domain (RBD) of MERS-CoV spike protein and DPP4 was determined by crystallography. Animal studies identified rhesus macaques but not hamsters, ferrets, or mice to be susceptible for MERS-CoV. Here, we investigated the role of DPP4 in this observed species tropism. Cell lines of human and nonhuman primate origin were permissive of MERS-CoV, whereas hamster, ferret, or mouse cell lines were not, despite the presence of DPP4. Expression of human DPP4 in nonsusceptible BHK and …

Epigenetic Dominance Of Prion Conformers, Eri Saijo, Hae-Eun Kang, Jifeng Bian, Kristi G. Bowling, Shawn Browning, Sehun Kim, Nora Hunter, Glenn C. Telling

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Although they share certain biological properties with nucleic acid based infectious agents, prions, the causative agents of invariably fatal, transmissible neurodegenerative disorders such as bovine spongiform encephalopathy, sheep scrapie, and human Creutzfeldt Jakob disease, propagate by conformational templating of host encoded proteins. Once thought to be unique to these diseases, this mechanism is now recognized as a ubiquitous means of information transfer in biological systems, including other protein misfolding disorders such as those causing Alzheimer's and Parkinson's diseases. To address the poorly understood mechanism by which host prion protein (PrP) primary structures interact with distinct prion conformations to influence pathogenesis, …

Asymmetric Dimethylarginine Blocks Nitric Oxide-Mediated Alcohol-Stimulated Cilia Beating., Todd A. Wyatt, S . M. Wells, Z . A. Alsaidi, Jane M. Devasure, E. B. Klein, Kristina L. Bailey, Joseph H. Sisson

Journal Articles: Pulmonary & Critical Care Med

The airway epithelium is exposed to alcohol during drinking through direct exhalation of volatized ethanol from the bronchial circulation. Alcohol exposure leads to a rapid increase in the cilia beat frequency (CBF) of bronchial epithelial cells followed by a chronic desensitization of cilia stimulatory responses. This effect is governed in part by the nitric oxide regulation of cyclic guanosine and adenosine monophosphate-dependent protein kinases (PKG and PKA) and is not fully understood. Asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthase, is implicated in the pathogenesis of several pulmonary disorders. We hypothesized that the inhibition of nitric oxide synthase …

Cattle-Related Injuries And Farm Management Practices On Kentucky Beef Cattle Farms, Steven R. Browning, Susan C. Westneat, Wayne T. Sanderson, Deborah B. Reed

Epidemiology and Environmental Health Faculty Publications

While working on farms with livestock increases the risk of injury among farm workers in comparison to other commodity farms, few studies have examined the role offarm management practices in association with the risk of cattle-related injury. We examined the farm management practices of Kentucky beef cattle farms in association with self-reported rates of cattle-related injuries among workers. We conducted a mail survey of a random sample of 2,500 members of the Kentucky Cattlemen's Association. Results from 1,149 farm operators who were currently raising beef cattle and provided complete survey response are reported. During the busy season, the principal operator …

Accuracy Of Micrometeorological Techniques For Detecting A Change In Methane Emissions From A Herd Of Cattle, Johannes Laubach, Mei Bai, Cesar S. Pinares-Patino, Frances A. Phillips, Travis A. Naylor, German Molano, Edgar A. Cardenas Rocha, David W. T Griffith

Faculty of Science, Medicine and Health - Papers: part A

Micrometeorological techniques are effective in measuring methane (CH4) emission rates at the herd scale, but their suitability as verification tools for emissions mitigation depends on the uncertainty with which they can detect a treatment difference. An experiment was designed to test for a range of techniques whether they could detect a change in weekly mean emission rate from a herd of cattle, in response to a controlled change in feed supply. The cattle were kept in an enclosure and fed pasture baleage, of amounts increasing from one week to the next. Methane emission rates were measured at the herd scale …

Draft Genome Sequence Of Ochrobactrum Pseudogrignonense Strain Cdb2, A Highly Efficient Arsenate-Resistant Soil Bacterium From Arsenic-Contaminated Cattle Dip Sites, Yiren Yang, Xuefei Yu, Ren Zhang

Faculty of Science, Medicine and Health - Papers: part A

We report the 4.97-Mb draft genome sequence of a highly efficient arsenate-resistant bacterium, Ochrobactrum sp. strain CDB2. It contains a novel arsenic resistance (ars) operon (arsR-arsC1-ACR3-arsC2-arsH-mfs) and two non-operon-associated ars genes, arsC3 and arsB. The genome information will aid in the understanding of the arsenic resistance mechanism of this and other bacterial species.

Non-Typeable Haemophilus Influenzae Decreases Cilia Beating Via Protein Kinase Cε., Kristina L. Bailey, Tricia D. Levan, Daniel A. Yanov, Jacqueline A. Pavlik, Jane M. Devasure, Joseph H. Sisson, Todd A. Wyatt

Journal Articles: Pulmonary & Critical Care Med

BACKGROUND: Haemophilus influenzae infection of the nasal epithelium has long been associated with observations of decreased nasal ciliary beat frequency (CBF) and injury to the ciliated epithelium. Previously, we have reported that several agents that slow CBF also have the effect of activating protein kinase C epsilon (PKCε) activity in bronchial epithelial cells. The subsequent auto-downregulation of PKCε or the direct inhibition of PKCε leads to the specific detachment of the ciliated cells.

METHODS: Primary cultures of ciliated bovine bronchial epithelial cells were exposed to filtered conditioned media supernatants from non-typeable H. influenzae (NTHi) cultures. CBF and motile points were …

Comparison Of Estrone And 17Β-Estradiol Levels In Commercial Goat And Cow Milk, D. W. Farlow, X. Xu, T. D. Veenstra

Pharmaceutical Sciences Faculty Publications

Increased levels of estrogen metabolites are believed to be associated with cancers of the reproductive system. One potential dietary source of these metabolites that is commonly consumed worldwide is milk. In North America, dairy cows are the most common source of milk; however, goats are the primary source of milk worldwide. In this study, the absolute concentrations of unconjugated and total (unconjugated plus conjugated) estrone (E(1)) and 17β-estradiol (E(2)) were compared in a variety of commercial cow milks (regular and organic) and goat milk. A lower combined concentration of E(1) and E(2) was found in goat milk than in any …

Identification Of Bovine Leukemia Virus Tax Function Associated With Host Cell Transcription, Signaling, Stress Response And Immune Response Pathway By Microarray-Based Gene Expression Analysis., Mariluz Araínga, Eri Takeda, Yoko Aida

Journal Articles: Pharmacology & Experimental Neuroscience

BACKGROUND: Bovine leukemia virus (BLV) is associated with enzootic bovine leukosis and is closely related to human T-cell leukemia virus type I. The Tax protein of BLV is a transcriptional activator of viral replication and a key contributor to oncogenic potential. We previously identified interesting mutant forms of Tax with elevated (TaxD247G) or reduced (TaxS240P) transactivation effects on BLV replication and propagation. However, the effects of these mutations on functions other than transcriptional activation are unknown. In this study, to identify genes that play a role in the cascade of signal events regulated by wild-type and mutant Tax proteins, we …

Tgfb1 Disrupts The Angiogenic Potential Of Microvascular Endothelial Cells Of The Corpus Luteum., Dulce Maroni, John S. Davis

Journal Articles: Obstetrics & Gynecology

Cyclical formation and regression of the ovarian corpus luteum is required for reproduction. During luteal regression, the microvasculature of the corpus luteum is extensively disrupted. Prostaglandin F2α, a primary signal for luteal regression, induces the expression of transforming growth factor β1 (TGFB1) in the corpus luteum. This study determined the actions of TGFB1 on microvascular endothelial cells isolated from the bovine corpus luteum (CLENDO cells). We hypothesized that TGFB1 participates in the disruption of the microvasculature during luteal regression. TGFB1 activated the canonical SMAD signaling pathway in CLENDO cells. TGFB1 (1 ng/ml) significantly reduced both basal and fetal-calf-serum-stimulated DNA synthesis, …

Endothelial Cell Capture Of Heparin-Binding Growth Factors Under Flow, Bing Zhao, Changjiang Zhang, Kimberly Forsten-Williams, Jun Zhang, Michael Fannon

Ophthalmology and Visual Science Faculty Publications

Circulation is an important delivery method for both natural and synthetic molecules, but microenvironment interactions, regulated by endothelial cells and critical to the molecule's fate, are difficult to interpret using traditional approaches. In this work, we analyzed and predicted growth factor capture under flow using computer modeling and a three-dimensional experimental approach that includes pertinent circulation characteristics such as pulsatile flow, competing binding interactions, and limited bioavailability. An understanding of the controlling features of this process was desired. The experimental module consisted of a bioreactor with synthetic endothelial-lined hollow fibers under flow. The physical design of the system was incorporated …

Incompatibility With Formin Cdc12p Prevents Human Profilin From Substituting For Fission Yeast Profilin: Insights From Crystal Structures Of Fission Yeast Profilin., Obidimma Ezezika, Noah S Younger, Jia Lu, Donald A Kaiser, Zachary A Corbin, Bradley J Nolen, David R Kovar, Thomas D Pollard

Health Studies Publications

Expression of human profilin-I does not complement the temperature-sensitive cdc3-124 mutation of the single profilin gene in fission yeast Schizosaccharomyces pombe, resulting in death from cytokinesis defects. Human profilin-I and S. pombe profilin have similar affinities for actin monomers, the FH1 domain of fission yeast formin Cdc12p and poly-L-proline (Lu, J., and Pollard, T. D. (2001) Mol. Biol. Cell 12, 1161-1175), but human profilin-I does not stimulate actin filament elongation by formin Cdc12p like S. pombe profilin. Two crystal structures of S. pombe profilin and homology models of S. pombe profilin bound to actin show how the two profilins bind …

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.

The Fgf System Has A Key Role In Regulating Vascular Integrity, Masahiro Murakami, Loc T. Nguyen, Zhen W. Zhang, Karen L. Moodie, Pater Carmellet, Radu V. Stan, Michael Simons

Dartmouth Scholarship

The integrity of the endothelial monolayer is essential to blood vessel homeostasis and active regulation of endothelial permeability. The FGF system plays important roles in a wide variety of physiologic and pathologic conditions; however, its role in the adult vasculature has not been defined. To assess the role of the FGF system in the adult endothelial monolayer, we disrupted FGF signaling in bovine aortic endothelial cells and human saphenous vein endothelial cells in vitro and in adult mouse and rat endothelial cells in vivo using soluble FGF traps or a dominant inhibitor of all FGF receptors. The inhibition of FGF …

A Functional Collagen Adhesin Gene, Acm, In Clinical Isolates Of Enterococcus Faecium Correlates With The Recent Success Of This Emerging Nosocomial Pathogen, Sreedhar R Nallapareddy, Kavindra V Singh, Pablo C Okhuysen, Barbara E Murray

Journal Articles

Enterococcus faecium recently evolved from a generally avirulent commensal into a multidrug-resistant health care-associated pathogen causing difficult-to-treat infections, but little is known about the factors responsible for this change. We previously showed that some E. faecium strains express a cell wall-anchored collagen adhesin, Acm. Here we analyzed 90 E. faecium isolates (99% acm(+)) and found that the Acm protein was detected predominantly in clinically derived isolates, while the acm gene was present as a transposon-interrupted pseudogene in 12 of 47 isolates of nonclinical origin. A highly significant association between clinical (versus fecal or food) origin and collagen adherence (P

Structure Of The Hsp110:Hsc70 Nucleotide Exchange Machine, Jonathan P Schuermann, Jianwen Jiang, Jorge Cuellar, Oscar Llorca, Liping Wang, Luis E Gimenez, Suping Jin, Alexander B Taylor, Borries Demeler, Kevin A Morano, P John Hart, Jose M Valpuesta, Eileen M Lafer, Rui Sousa

Journal Articles

Hsp70s mediate protein folding, translocation, and macromolecular complex remodeling reactions. Their activities are regulated by proteins that exchange ADP for ATP from the nucleotide-binding domain (NBD) of the Hsp70. These nucleotide exchange factors (NEFs) include the Hsp110s, which are themselves members of the Hsp70 family. We report the structure of an Hsp110:Hsc70 nucleotide exchange complex. The complex is characterized by extensive protein:protein interactions and symmetric bridging interactions between the nucleotides bound in each partner protein's NBD. An electropositive pore allows nucleotides to enter and exit the complex. The role of nucleotides in complex formation and dissociation, and the effects of …

Sheep Updates 2008 - Part 2, Meredith L. Sheil, Di Evans, Brown Besier, Tim Scanlon, Andre Martinho De Almeida, Johan Greeff, Tanya Kilminster, John Milton, Chris Oldham, B. L. Mcintyre, Alison Wheatley, John Lucey, Fiona Jones, Nick Costa, Ed Riggall, J. R. L. Hall, Robin Jacob, Dave Pethick, Dave Hopkins, Graham Gardner

Sheep Updates

This session covers eleven papers from different authors: The Sheep Room 1. Analgesia for Surgical Husbandry Procedures in Sheep and Other Livestock, Dr Meredith L. Sheil, Animal Ethics Pty Ltd, Associate Sydney University Faculty of Veterinary Science The Wool Enterprise 2. Unmulsed sheep - implications for chemical use, Di Evans & Brown Besier, Department of Agriculture and Food WA 3. Are Damara and Dorper sheep better adapted than Merinos to nutritional stress? - Growth rates, Tim Scanlon1, Andre Martinho de Almeida2, Johan Greeff1, Tanya Kilminster1, John Milton3, Chris Oldham1, Department of Agriculture and Food WA1, Instituto de Investigacao Cientifica Tropical, …

Bovine Oocytes And Early Embryos Express Staufen And Elavl Rna-Binding Proteins., M D Calder, P Madan, A J Watson

Obstetrics & Gynaecology Publications

RNA-binding proteins (RBP) influence RNA editing, localization, stability and translation and may contribute to oocyte developmental competence by regulating the stability and turnover of oogenetic mRNAs. The expression of Staufen 1 and 2 and ELAVL1, ELAVL2 RNA-binding proteins during cow early development was characterized. Cumulus-oocyte complexes were collected from slaughterhouse ovaries, matured, inseminated and subjected to embryo culture in vitro. Oocyte or preimplantation embryo pools were processed for RT-PCR and whole-mount immunofluorescence analysis of mRNA expression and protein distribution. STAU1 and STAU2 and ELAVL1 mRNAs and proteins were detected throughout cow preimplantation development from the germinal vesicle (GV) oocyte to …

Reduced Intestinal Colonization Of Adult Beef Cattle By Escherichia Coli O157:H7 Tir Deletion And Nalidixic-Acid-Resistant Mutants Lacking Flagellar Expression, Gustavo Bretschneider, Emil M. Berberov, Rodney A. Moxley

School of Veterinary and Biomedical Sciences: Faculty Publications

The importance of the Escherichia coli O157:H7 translocated intimin receptor (Tir) protein in intestinal colonization and the effect of infection with Tir⁺ strains on protection against subsequent challenge was studied in adult beef cattle. Cattle were orally inoculated (C1) with a Shiga toxin-2⁺+ E. coli O157:H7 strain that was Tir⁺ or Tir^-, and 42 days later were re-challenged (C2) with the nalidixic acid (Nal) ^R parent strain to test whether prior infection had any effect on fecal shedding. During the first 14 days post-C1, the Nal^S wildtype (WT) strain was shed at significantly …

Modulation Of Tgf-Beta Signaling By Proinflammatory Cytokines In Articular Chondrocytes., Jorge A. Roman-Blas, David G. Stokes, Sergio A. Jimenez

Department of Medicine Faculty Papers

OBJECTIVE: The normal structure and function of articular cartilage are the result of a precisely balanced interaction between anabolic and catabolic processes. The transforming growth factor-beta (TGF-beta) family of growth factors generally exerts an anabolic or repair response; in contrast, proinflammatory cytokines such as interleukin 1 beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) exert a strong catabolic effect. Recent evidence has shown that IL-1beta, and TNF-alpha, and the TGF-beta signaling pathways share an antagonistic relationship. The aim of this study was to determine whether the modulation of the response of articular chondrocytes to TGF-beta by IL-1beta or TNF-alpha signaling pathways …

Isotype-Specific Antibody Responses Against Escherichia Coli O157:H7 Locus Of Enterocyte Effacement Proteins In Adult Beef Cattle Following Experimental Infection, G. Bretschneider, E. M. Berberov, Rodney A. Moxley

School of Veterinary and Biomedical Sciences: Faculty Publications

Escherichia coli O157:H7 is an important food-borne pathogen and cause of hemorrhagic colitis and hemolytic uremic syndrome in humans. Cattle are an important reservoir of E. coli O157:H7, in which the organism colonizes the intestinal tract and is shed in the feces. Vaccination of cattle has significant potential as a pre-harvest intervention strategy for E. coli O157:H7; however, basic information about the bovine immune responses to important bacterial colonization factors resulting from infection has not been reported. The serum and fecal IgG and IgA antibody responses of adult cattle to E. coli O157:H7 intimin, translocated intimin receptor (Tir), E. coli …

Bovine Immune Response To Shiga-Toxigenic Escherichia Coli O157:H7., Mark A Hoffman, Christian Menge, Thomas A Casey, William Laegreid, Brad T Bosworth, Evelyn A Dean-Nystrom

Manuscripts, Articles, Book Chapters and Other Papers

Although cattle develop humoral immune responses to Shiga-toxigenic (Stx+) Escherichia coli O157:H7, infections often result in long-term shedding of these human pathogenic bacteria. The objective of this study was to compare humoral and cellular immune responses to Stx+ and Stx- E. coli O157:H7. Three groups of calves were inoculated intrarumenally, twice in a 3-week interval, with different strains of E. coli: a Stx2-producing E. coli O157:H7 strain (Stx2+ O157), a Shiga toxin-negative E. coli O157:H7 strain (Stx- O157), or a nonpathogenic E. coli strain (control). Fecal shedding of Stx2+ O157 was significantly higher than that of Stx- O157 or the …

Comparative Analysis Of Vertebrate Eif2ak2 (Pkr) Genes And Assignment Of The Equine Gene To Eca15q24-Q25 And The Bovine Gene To Bta11q12-Q15, Andrey A. Perelygin, Teri L. Lear, Andrey A. Zharkikh, Margo A Brinton

Veterinary Science Faculty Publications

The structures of the canine, rabbit, bovine and equine EIF2AK2 genes were determined. Each of these genes has a 5' non-coding exon as well as 15 coding exons. All of the canine, bovine and equine EIF2AK2 introns have consensus donor and acceptor splice sites. In the equine EIF2AK2 gene, a unique single nucleotide polymorphism that encoded a Tyr329Cys substitution was detected. Regulatory elements predicted in the promoter region were conserved in ungulates, primates, rodents, Afrotheria (elephant) and Insectifora (shrew). Western clawed frog and fugu EIF2AK2 gene sequences were detected in the USCS Genome Browser and compared to those of other …

Ligand-Signaled Upregulation Of Enterococcus Faecalis Ace Transcription, A Mechanism For Modulating Host-E Faecalis Interaction, Sreedhar R Nallapareddy, Barbara E Murray

Journal Articles

Enterococcus faecalis, the third most frequent cause of bacterial endocarditis, appears to be equipped with diverse surface-associated proteins showing structural-fold similarity to the immunoglobulin-fold family of staphylococcal adhesins. Among the putative E. faecalis surface proteins, the previously characterized adhesin Ace, which shows specific binding to collagen and laminin, was detectable in surface protein preparations only after growth at 46 degrees C, mirroring the finding that adherence was observed in 46 degrees C, but not 37 degrees C, grown E. faecalis cultures. To elucidate the influence of different growth and host parameters on ace expression, we investigated ace expression using E. …

Mitogen-Activated Protein Kinase (Mapk) Blockade Of Bovine Preimplantation Embryogenesis Requires Inhibition Of Both P38 And Extracellular Signal-Regulated Kinase (Erk) Pathways., Pavneesh Madan, Michele D Calder, Andrew J Watson

Obstetrics & Gynaecology Publications

Blastocyst formation, as a critical period during development, is an effective indicator of embryonic health and reproductive efficiency. Out of a number of mechanisms underlying blastocyst formation, highly conserved mitogen-activated protein kinase (MAPK) signaling has emerged as a major mechanism involved in regulating murine preimplantation embryo development. The objective of our study was to ascertain the role of MAPK signaling in regulating bovine development to the blastocyst stage. Using reverse transcriptase PCR and immunohistochemical staining procedures we have demonstrated that mRNA transcripts and polypeptides encoding p38 MAPK pathway constituents are detectable in preimplantation bovine embryos from the one-cell to the …

Manganese Distribution Across The Blood-Brain Barrier. Iv. Evidence For Brain Influx Through Store-Operated Calcium Channels, Janelle S. Crossgrove, Robert A. Yokel

Pharmaceutical Sciences Faculty Publications

Manganese (Mn) is a required co-factor for many ubiquitous enzymes; however, chronic Mn overexposure can cause manganism, a parkinsonian-like syndrome. Previous studies showed Mn influx into brain is carrier-mediated, though the putative carrier(s) were not established. Studies conducted with cultured bovine brain microvascular endothelial cells (bBMECs), which comprise the blood–brain barrier, revealed ⁵⁴Mn (II) uptake positively correlated with pH, was temperature-dependent, and was sodium- and energy-independent. Brain ⁵⁴Mn uptake correlated inversely with calcium (Ca) concentration, but ⁴⁵Ca uptake was unaltered by high Mn concentration. Lanthanum (La), a non-selective inhibitor of several Ca channel types, as well as …