Medicine and Health Sciences Commons^™

Epidemiology Of Escherichia Coli O157:H7 Outbreaks, United States, 1982–2002, Josefa M. Rangel, Phyllis H. Sparling, Collen Crowe, Patricia M. Griffin, David L. Swerdlow

Public Health Resources

Escherichia coli O157:H7 causes 73,000 illnesses in the United States annually. We reviewed E. coliO157 outbreaks reported to Centers for Disease Control and Prevention (CDC) to better understand the epidemiology of E. coli O157. E. coli O157 outbreaks (>2 cases of E. coli O157 infection with a common epidemiologic exposure) reported to CDC from 1982 to 2002 were reviewed. In that period, 49 states reported 350 outbreaks, representing 8,598 cases, 1,493 (17%) hospitalizations, 354 (4%) hemolytic uremic syndrome cases, and 40 (0.5%) deaths. Transmission route for 183 (52%) was foodborne, 74 (21%) unknown, 50 (14%) person-to-person, 31 (9%) …

Effect Of Cirrhosis On Antibiotic Efficacy In A Rat Model Of Pneumococcal Pneumonia, Laurel C. Preheim, Keith M. Olsen, Mei Yue, Mary U. Snitily, Martha J. Gentry-Nielsen

Public Health Resources

A rat model was used to study the effects of cirrhosis on antibiotic therapy of pneumococcal pneumonia. Cirrhotic and control male Sprague-Dawley rats were infected transtracheally with type 3 Streptococcus pneumonia. Treatment began 18 h later with phosphate-buffered saline (PBS), azithromycin (50 mg/kg), trovafloxacin (50 mg/kg), or ceftriaxone (100 mg/kg) injected subcutaneously twice daily for 5 days. Antibiotic concentrations were measured by high-performance liquid chromatography. Azithromycin, trovafloxacin, and ceftriaxone were all equally effective at preventing mortality in both cirrhotic and normal rats. Free fraction area under the curve to minimum inhibitory concentration ratio (AUC/MIC) and maximum calculated serum concentration …

Molecular Cloning And Characterization Of A Porcine Ul16 Binding Protein (Ulbp)-Like Cdna, Carmen N. Garcia-Borges, Bounleut Phanavanh, Sarika Saraswati, Richard A. Dennis, Mark D. Crew

Public Health Resources

UL16 binding proteins (ULBPs) are ligands for the NK cell activating receptor NKG2D. A cDNA encoding a porcine ULBP-like protein (PULBP) was cloned and the predicted amino acid sequence exhibited 35–52% identity to human ULBPs. Southern blot analysis suggested that there is only one ULBP-like gene in the pig genome. Transcripts of PULBP and another potential NKG2D ligand, MIC2, were detected by RT-PCR in a wide range of tissues. Recombinant PULBP-Fc and human ULBP2-Fc fusion proteins were made and used to examine PULBP binding to porcine PBMCs and a human NK cell line (NKL cells). PULBP-Fc bound to a subpopulation …

Phylogenetic Analysis Of North American West Nile Virus Isolates, 2001–2004: Evidence For The Emergence Of A Dominant Genotype, C. Todd Davis, Gregory D. Ebel, Robert S. Lanciotti, Aaron C. Brault, Hilda Guzman, Marina Siirin, Amy Lambert, Ray E. Parsons, David W.C. Beasley, Robert J. Novak, Darwin Elizondo-Quiroga, Emily N. Green, David S. Young, Lillian M. Stark, Michael A. Drebot, Harvey Artsob, Robert B. Tesh, Laura D. Kramer, Alan D.T. Barrett

Public Health Resources

The distribution of West Nile virus has expanded in the past 6 years to include the 48 contiguous United States and seven Canadian provinces, as well as Mexico, the Caribbean islands, and Colombia. The suggestion of the emergence of a dominant genetic variant has led to an intensive analysis of isolates made across North America. We have sequenced the premembrane and envelope genes of 74 isolates and the complete genomes of 25 isolates in order to determine if a dominant genotype has arisen and to better understand how the virus has evolved as its distribution has expanded. Phylogenetic analyses revealed …

Agricultural Pesticide Use And Risk Of Glioma In Nebraska, United States, W. J. Lee, J. S. Colt, E. F. Heineman, R. Mccomb, D. D. Weisenburger, W. Lijinsky, M. H. Ward

Public Health Resources

Background: To evaluate the risk of the adult glioma associated with farming and agricultural pesticide use, the authors conducted a population based case control study in eastern Nebraska.
Methods: Telephone interviews were conducted with men and women diagnosed with gliomas (n = 251) between 1988 and 1993 and controls (n = 498) randomly selected from the same geographical area. Unconditional logistic regression was used to calculate adjusted odds ratios (ORs) for farming and for use of individual and chemical classes of insecticides and herbicides, including pesticides classified as nitrosatable (able to form N-nitroso compounds upon reaction with nitrite). Non-farmers were …

Role Of Elevated S-Adenosylhomocysteine In Rat Hepatocyte Apoptosis: Protection By Betaine, Kusum K. Kharbanda, David D. Rogers Ii, Mark E. Mailliard, Gerri L. Siford, Anthony J. Barak, Harriet C. Beckenhauer, Michael F. Sorrell, Dean J. Tuma

Public Health Resources

Previous studies from our laboratory have shown that ethanol consumption results in an increase in hepatocellular S-adenosylhomocysteine levels. Because S-adenosylhomocysteine is a potent inhibitor of methylation reactions, we propose that increased intracellular S-adenosylhomocysteine levels could be a major contributor to ethanol-induced pathologies. To test this hypothesis, hepatocytes isolated from rat livers were grown on collagen-coated plates in Williams’ medium E containing 5% FCS and exposed to varying concentrations of adenosine in order to increase intracellular S-adenosylhomocysteine levels. We observed increases in caspase-3 activity following exposure to adenosine. This increase in caspase activity correlated with increases in intracellular S-adenosylhomocysteine levels and …

Measurements Of Constraint Of Total Knee Replacement, H. Haider, P.S. Walker

Public Health Resources

Measurement of the constraint of total knee components in a test machine provides an objective method of describing the laxity and stability characteristics of the implant itself, independent of the knee joint into which it would be implanted. A special fixture was designed and fitted to a Bionix multi-channel loading machine. The test consisted of applying a compressive load, applying a cyclic AP force or internal-external torque, and measuring all of the displacements and rotations. Three different commonly-used TKR’s showed widely different constraint characteristics. In the cyclic AP test, along with the cyclic AP displacement, displacements and rotations occurred in …

Rat Sinusoidal Liver Endothelial Cells (Secs) Produce Pro-Fibrotic Factors In Response To Adducts Formed From The Metabolites Of Ethanol, Geoffrey M. Thiele, Michael J. Duryee, Thomas L. Freeman, Michael F. Sorrell, Monte S. Willis, Dean J. Tuma, Lynell W. Klassen

Public Health Resources

Previous studies with alcohol-associated malondialdehyde–acetaldehyde (MAA)-modified proteins have demonstrated an increase in the expression of adhesion molecules, and the secretion of pro-inflammatory cytokines/chemokines by rat sinusoidal liver endothelial cells (SECs). However, no studies have been initiated to examine the effects of MAA-modified proteins on the expression of the extracellular matrix (ECM) protein, fibronectin and its isoforms. For these studies, SECs were isolated from the liver of normal rats, and exposed to MAA-modified bovine serum albumin (MAA–Alb). At selected time points, the total plasma and cellular fibronectin were determined by Western blot. Injection of rat liver via the mesenteric vein with …

Genome Size And Organization In The Blacklegged Tick, Ixodes Scapularis And The Southern Cattle Tick, Boophilus Microplus, A. J. Ullmann, C. M. R. Lima, F. D. Guerrero, J. Piesman, W. C. Black Iv

Public Health Resources

Genome sizes and the organization of repetitive DNA were determined in the hard ticks Ixodes scapularis and Boophilus microplus using reassociation kinetics. The I. scapularis genome contains ~ 2.15 pg (2.1 × 10 ³ Mbp) of DNA and consists of no foldback (FB), 27% highly repetitive (HR), 39% moderately repetitive (MR), and 34% unique DNA. The B. microplus genome contains 7.5 pg (7.1 × 10 ³ Mbp) DNA, and consists of 0.82% FB, 31% HR, 38% MR, and 30% unique DNA. In both species, repetitive sequences occur in a mixture of long and short period interspersion but most (65–80%) of …

Evolutionary Genetics Of A New Pathogenic Escherichia Species: Escherichia Albertii And Related Shigella Boydii Strains, Katie E. Hyma, David W. Lacher, Adam M. Nelson, Alyssa C. Bumbaugh, J. Michael Janda, Nancy A. Strockbine, Vincent B. Young, Thomas S. Whittam

Public Health Resources

A bacterium originally described as Hafnia alvei induces diarrhea in rabbits and causes epithelial damage similar to the attachment and effacement associated with enteropathogenic Escherichia coli. Subsequent studies identified similar H. alvei-like strains that are positive for an intimin gene (eae) probe and, based on DNA relatedness, are classified as a distinct Escherichia species, Escherichia albertii. We determined sequences for multiple housekeeping genes in five E. albertii strains and compared these sequences to those of strains representing the major groups of pathogenic E. coli and Shigella. A comparison of 2,484 codon positions in 14 …

Non-O157 Shiga Toxin–Producing Escherichia Coli Infections In The United States, 1983–2002, John T. Brooks, Evangeline G. Sowers, Joy G. Wells, Katherine D. Greene Greene, Patricia M. Griffin, Robert M. Hoekstra, Nancy A. Strockbine

Public Health Resources

Background. Shiga toxin–producing Escherichia coli (STEC) O157:H7 is a well-recognized cause of bloody diarrhea and hemolytic-uremic syndrome (HUS). Non-O157 STEC contribute to this burden of illness but have been underrecognized as a result of diagnostic limitations and inadequate surveillance.

Methods. Between 1983 and 2002, 43 state public health laboratories submitted 940 human non-O157 STEC isolates from persons with sporadic illnesses to the Centers for Diseases Control and Prevention reference laboratory for confirmation and serotyping.

Results. The most common serogroups were O26 (22%), O111 (16%), O103 (12%), O121 (8%), O45 (7%), and O145 (5%). Non-O157 STEC infections were …

Identification And Characterization Of Shigella Boydii 20 Serovar Nov., A New And Emerging Shigella Serotype, David L. Woodward, Clifford G. Clark, Richard A. Caldeira, Rafiq Ahmed, Geoff Soule, Louis Bryden, Helen Tabor, Pasquale Melito, Roger Foster, Julie Walsh, Lai-King Ng, Georgia B. Malcolm, Nancy Strockbine, Frank G. Rodgers

Public Health Resources

Analysis of 163 putative Shigella isolates from Canada and the USA showed biochemical reactions consistent with Shigella species, although none of the isolates reacted with antiserum raised against any of the well-established or provisional Shigella serotypes. All these isolates, provisionally designated serotype SH108, were positive for the ipaH gene and the invasion-associated locus. All fermented mannitol, were serologically indistinguishable from each other and showed no reaction in antisera prepared against Escherichia coli serotypes O1 to O181. PCR-RFLP analysis of the genes involved in O-antigen synthesis revealed a common pattern among these isolates that was distinct from recognized Shigella serotypes and …

Evaluating Current Policy For Detecting Mosaicism In Amniotic Fluid Cultures: Implications For Current Cell Counting Practices, Samuel P. Caudill, Daniel L. Van Dyke, Andrew T. L. Chen, John A. Reidy, Paul S. Ing, Stuart Schwartz, Gail H. Vance

Public Health Resources

Chromosomal mosaicism is one of the most vexing problems for clinical cytogenetic laboratories and personnel time used for analysis at the microscope is one of the principle costs in cytogenetic laboratories. We use data collected from 26 cytogenetic laboratories to evaluate whether the American College of Medical Genetics guidelines for minimum number of cells to count to exclude mosaicism in amniotic fluid specimens is appropriate. An accurate estimate of the number of mosaics that are missed by current cell counting practices is an important step in this process. Thus, we present a new method for estimating the number of mosaics …