Pathophysiology of Arbroviral Encephalitides in Laboratory Rodents

Western equine encephalitis virus (WEEV) is an arboviral pathogen naturally found in North America. The primary disease phenotype associated with WEEV infection in susceptible hosts is a relatively long prodromal period followed by viral encephalitis. By contrast, in the current work, experimental inoculation of WEEV into the peritoneum of Syrian golden hamsters produced rapid death within approximately 96 h. It was determined that direct virus killing of lymphoid cells leads to death in WEEV-infected Syrian golden hamsters, and that inflammatory cytokines have the potential to enhance virus-induced lymphoid cell destruction. It was further concluded that WEEV retains its ability to cause encephalitis in Syrian golden hamsters, if hamsters survive the early stages of virus infection or if virus is introduced directly into the CNS. Death in WEEV-infected hamsters is associated with lymphonecrotic lesions in the absence of pathological lesions in the central nervous system (CNS). Few clinical parameters were altered by WEEV infection, with the exception of circulating lymphocyte numbers. Circulating lymphocyte numbers decreased dramatically during WEEV infection, and lymphopenia was identified as a consistent indicator of eventual death. Virus infection also increased serum concentrations of the cytokines interferon and tumor necrosis factor-alpha (TNF-alpha). Hamster peritoneal macrophages exposed to WEEV expressed TNF-alpha in a dose-responsive manner. Macrophage expression of TNF-alpha could be significantly inhibited by treatment of cells with anti-inflammatory agents flunixin meglumine (FM) or dexamethasone (Dex). Anti-inflammatory treatment also protected macrophages from cytotoxicity associated with exposure to WEEV. Treatment of WEEV-infected hamsters with either FM or Dex significantly improved survival compared to placebo-treated controls. WEEV induced cytotoxicity in hamster splenocytes exposed to WEEV in a virus dose-responsive manner. Supernatant from WEEV-exposed macrophages significantly enhanced WEEV killing of splenocytes. Hamsters that survived the early stages of WEEV infection occasionally developed signs of neurological disease and died approximately 6 to 9 d after virus inoculation. These animals had histopathological lesions in the CNS consistent with alphavirus-induced encephalitis. Inoculation of WEEV directly into the CNS caused apparent encephalitic disease. Death following CNS inoculation of WEEV was rapid and concurrent with histopathological lesions in the CNS similar to lesions seen in encephalitic hamsters following peripheral inoculation

The Value of Knowing: Public Lands Monitoring by Non-Agency Groups

It is generally recognized that in order to make informed federal land management decisions, such decisions need to be based on information gathered from monitoring of those lands. While some monitoring is being conducted by federal land management agencies, it is happening too infrequently and is often inadequate for properly informing land management decisions. In an attempt to fill this gap non-agency groups have begun monitoring federal public lands themselves. It appears that through recent congressional authorizations, policy reforms, and agency initiatives monitoring by non-agency groups is being supported at every government level. While theoretically this transfer of responsibility from the federal agencies to non-agency groups looks good on paper in reality there are considerable barriers. This has many groups gathering data that ends up never being used in the decision making process. Despite this barrier, however, non-agency groups continue to monitor while the topic itself garners increased attention. As it stands, our understanding of how non-agency monitoring can affect land management decision making is seen as fairly black and white; data from monitoring is either used by the agency to make decisions or it is not. This study suggests that such a view of monitoring by non-agency groups is too narrow. The values associated with monitoring on federal public lands can be seen as having an internal or external benefit. Internal benefits, such as engaging youth or leveraging funding, are those that primarily only affect the monitoring group. External benefits, such as filling in gaps of agency monitoring or informing adaptive management within the agency, are those that may lead to either directly or indirectly influencing land management decision making. Ultimately, directly influencing federal land management decision making is difficult and may be out of reach for many non-agency groups. However those benefits that affect the group itself may be easier to achieve and could act as a starting point for groups wanting to start monitoring. Over time external benefits can be realized such as building relationships with agency staff, building public support, or informing NEPA reports that can lead to indirectly influencing federal land management decision making. Furthermore, there are differences between how single-interest groups and multi-interest groups value monitoring. Combined, these insights can assist groups in focusing their monitoring goals in order to increase the longevity and success of monitoring activity

Therapist Characteristics Influencing Physical Therapy Non-Treatment in the Acute Care Setting

Background and Purpose: Research has found that participation in physical therapy (PT) services in the acute care setting increases functional outcomes and decreases patient length of stay. Certain physical therapist characteristics could be a potential source of influence on patient non-participation in physical therapy in the acute care setting. The purpose of this study was to determine whether specific characteristics of therapists and patients are predictive of physical therapy non-treatment. Subjects: Subjects included 16 physical therapists or physical therapist assistants and 1225 patients at a community acute care hospital. Methods: Characteristics of each therapist and their corresponding patient data were collected from the 16 therapists at a community acute care hospital. Logistic regression was used to identify any therapist or patient factors predictive of patient non-participation in physical therapy services during their second scheduled visit. Results: Odds ratios were found to be significant for the following variables: Wednesday, the “Other diagnosis” grouping, and 2 out of the 14 therapists. Odds ratios for these variables were 0.455, 2.146, 8.804, and 10.359 respectively. Discussion and conclusion: No surveyed therapist characteristics were predictive of non-participation of physical therapy treatment in the acute care setting. Though measured attributes were not predictive, being a specific therapist, patients fitting into the “other” diagnosis category and being treated on Wednesday were predictive of non-treatment. Future research should focus on evaluating further therapist characteristics not included in this study, such as personality traits

Distances to Populous Clusters in the LMC via the K-Band Luminosity of the Red Clump

We present results from a study of the distances and distribution of a sample of intermediate-age clusters in the Large Magellanic Cloud. Using deep near-infrared photometry obtained with ISPI on the CTIO 4m, we have measured the apparent K-band magnitude of the core helium burning red clump stars in 17 LMC clusters. We combine cluster ages and metallicities with the work of Grocholski & Sarajedini to predict each cluster's absolute K-band red clump magnitude, and thereby calculate absolute cluster distances. An analysis of these data shows that the cluster distribution is in good agreement with the thick, inclined disk geometry of the LMC, as defined by its field stars. We also find that the old globular clusters follow the same distribution, suggesting that the LMC's disk formed at about the same time as the globular clusters, ~ 13 Gyr ago. Finally, we have used our cluster distances in conjunction with the disk geometry to calculate the distance to the LMC center, for which we find (m-M)o = 18.40 +/- 0.04_{ran} +/- 0.08_{sys}, or Do = 47.9 +/- 0.9 +/- 1.8 kpc.Comment: 31 pages including 5 figures and 7 tables. Accepted for publication in the August 2007 issue of A

Effect of Measurement Density on Characterizing Air Velocity Distribution in Commercial Broiler Houses

Increasing air velocity of tunnel ventilation systems in commercial broiler facilities improves production efficiency. As a consequence, many housing design specifications require a minimum air velocity in the house. Air velocities are typically assessed with a hand-held anemometer at random locations, rather than systematic traverses. Simultaneous measurement of air velocity at multiple locations in the facility would provide a more accurate estimation of air velocity distribution. The objective of this study was to assess the effect of measurement density on accuracy of estimating air velocity distribution in a tunnel-ventilated broiler production facility. An array of 40 anemometers was placed on a series of transverse cross-sections in a commercial broiler production facility with curtain sidewalls (no birds present) measuring 12.8 × 121.9 m. The house was equipped with ten 121.9 cm exhaust fans. Cross-sectional air velocity measurements were taken along the length of the house in increments of 3.05 m axially. Data were sampled at 1 Hz for 2 min; three 2 min subsamples were obtained at each cross-section. Horizontal plane air velocity distribution maps were generated using 12.19, 6.10, and 3.05 m axial measurement distances between cross-sections at 0.46 m above the litter. Vertical plane air velocity distribution maps were created using 10, 20, and 40 symmetrical sampling points from the original data set. Cross-validation analysis revealed that higher spatial measurement density in the axial direction yielded a higher correlation between observed and predicted values (79%) and lower mean squared prediction error (MSPE; 0.10 m s-1) when compared to decreased sampling densities. Vertical cross-section measurement density comparisons showed a reduction in MSPE and an increase in correlation between observed and predicted values at higher sampling densities in all cases tested excluding one. In the case of improved interpolation results with fewer measurement points, the cross-section demonstrated high variation in air velocity and velocity values being very low. Axial cross-sectional measurement distances of =3.05 m and vertical plane measurement densities of =40 measurement points should be used to accurately characterize air velocity distribution in a 12.8 × 121.9 m broiler production facility. Although more sensors and time are required to collect 40-point cross-sections at 3.05 m, the improved visualization allows better identification of distribution effects caused by equipment placement in the facility

Evolution of eukaryotic transcription : insights from the genome of Giardia lamblia

Author Posting. © Cold Spring Harbor Laboratory Press, 2004. This article is posted here by permission of Cold Spring Harbor Laboratory Press for personal use, not for redistribution. The definitive version was published in Genome Research 14 (2004): 1537-1547, doi:10.1101/gr.2256604.The Giardia lamblia genome sequencing project affords us a unique opportunity to conduct comparative analyses of core cellular systems between early and late-diverging eukaryotes on a genome-wide scale. We report a survey to identify canonical transcription components in Giardia, focusing on RNA polymerase (RNAP) subunits and transcription-initiation factors. Our survey revealed that Giardia contains homologs to 21 of the 28 polypeptides comprising eukaryal RNAPI, RNAPII, and RNAPIII; six of the seven RNAP subunits without giardial homologs are polymerase specific. Components of only four of the 12 general transcription initiation factors have giardial homologs. Surprisingly, giardial TATA-binding protein (TBP) is highly divergent with respect to archaeal and higher eukaryotic TBPs, and a giardial homolog of transcription factor IIB was not identified. We conclude that Giardia represents a transition during the evolution of eukaryal transcription systems, exhibiting a relatively complete set of RNAP subunits and a rudimentary basal initiation apparatus for each transcription system. Most class-specific RNAP subunits and basal initiation factors appear to have evolved after the divergence of Giardia from the main eukaryotic line of descent. Consequently, Giardia is predicted to be unique in many aspects of transcription initiation with respect to paradigms derived from studies in crown eukaryotes.This work was supported in part by NIH grant AI43273 to M.L.S., by NIH grant AI51089 to A.G.M, and DOE grant DE-FG02-01ER63201 to G.J.O. Additional support was provided by the G. Unger Vetlesen Foundation and LI-COR Biotechnology

Effects of pH on redox proxies in a Jurassic rift lake : implications for interpreting environmental records in deep time

This work was supported at the University of California, Riverside by the NSF-EAR FESD Program and the NASA Astrobiology Institute under Cooperative Agreement No. NNA15BB03A issued through the Science Mission Directorate. We thank Roger Buick (UW) for financial support of the carbon and nitrogen isotope work. EES acknowledges support from a NASA postdoctoral fellowship, as well as valuable discussions about the Newark basin with Charlotte B. Schreiber. GDL thanks the Agouron Institute for providing funding for the Waters Autospec GC-MS instrument at UCR.It is widely agreed that the Earth’s atmosphere and oceans have undergone major redox changes over the last 2.5 billion years. However, the magnitude of these shifts remains a point of debate because it is difficult to reconstruct concentrations of dissolved O2 from indirect proxies in sedimentary archives. In this study, we show that an additional complicating factor that is rarely considered may be the pH of the water column. We analyzed rock samples from the early Jurassic Towaco Formation in the Newark basin (eastern USA), comprising deposits of a rift lake that became temporarily redox stratified. New biomarker evidence points to increasingly saline aquatic conditions during the second half of the lake’s history, with a salinity stratification that induced redox stratification, including evidence for water column anoxia, and that state may also explain the disappearance of macrofauna at this time. Distinctive lipid biomarker assemblages and stable nitrogen isotope data support previous mineralogical indications that the lake was alkaline (pH ≥ 9) during its saline episode. Despite the biomarker and macrofaunal evidence for anoxia, ratios of Fe/Al and FeHR/FeT show only small to no enrichments in the anoxic horizon compared to oxic facies in the same section – counter to what is commonly observed in anoxic marine settings. Molybdenum, As, V, U and to some degree Cd show enrichments in the anoxic interval, whereas Co, Ni, Cu, Zn and Cr do not. These patterns are most parsimoniously explained by differential pH effects on the solubility of these elements. Extrapolating from these observations in lacustrine strata, we speculate that a secular increase in seawater pH over Earth’s history as recently proposed may have helped modulate the magnitude of trace metal enrichments in marine shales, although other factors such as atmospheric and oceanic redox likely dominated the observed enrichment patterns. Further, a decrease in the solubility of ferrous iron, a major O2 sink, with increasing pH may have contributed to ocean oxygenation. In summary, our results highlight the potential importance of pH in influencing global biogeochemical cycles for multiple elements and for the interpretation of ancient nitrogen isotope signatures.PostprintPeer reviewe

Optimization of Ectopic Gene Expression in Skeletal Muscle Through DNA Transfer by Electroporation.

Background Electroporation (EP) is a widely used non-viral gene transfer method. We have attempted to develop an exact protocol to maximize DNA expression while minimizing tissue damage following EP of skeletal muscle in vivo. Specifically, we investigated the effects of varying injection techniques, electrode surface geometry, and plasmid mediums. Results We found that as the amount of damage increased in skeletal muscle in response to EP, the level of β-galactosidase (β-gal) expression drastically decreased and that there was no evidence of β-gal expression in damaged fibers. Two specific types of electrodes yielded the greatest amount of expression. We also discovered that DNA uptake in skeletal muscle following intra-arterial injection of DNA was significantly enhanced by EP. Finally, we found that DMSO and LipoFECTAMINE™, common enhancers of DNA electroporation in vitro, had no positive effect on DNA electroporationin vivo. Conclusions When injecting DNA intramuscularly, a flat plate electrode without any plasmid enhancers is the best method to achieve high levels of gene expression