bluuebunny/crossref_metadata_2025 huggingface dataset:
The timeline of metalloprotease events during oligofructose induced equine laminitis development
Authors: VISSER M. B. , POLLITT C. C.
Published: June 2011

Reason for performing study: The role of matrix metalloproteases (MMPs) and the timeline of proteolysis during laminitis development are incompletely understood.

Objectives: To determine the temporal progression of selected MMPs and protease regulators during laminitis development.

Methods: Five clinically normal Standardbred horses received, via nasogastric intubation, an oligofructose (OF) bolus (10 g/kg bwt). Laminitis induction proceeded for 48 h followed by euthanasia. Lamellar biopsies were obtained prior to dosing and at intervals during the treatment period for analysis (12, 18, 24, 30 and 36 h and at 48 h following euthanasia). Tissue samples were analysed by real‐time PCR, zymography and western blotting.

Results: Activation of proMMP‐2 occurs either simultaneously or at least 12 h following lamellar basement membrane (BM) damage, while no activation of proMMP‐9 is seen during OF laminitis induction. Aggrecanase gene expression increased initially at 12–18 h post OF dosing, similar to BM changes. Gene expression of TIMP‐2, a MMP regulator, decreases during laminitis development.

Conclusions: The MMP‐2/MT1‐MMP complex may not play a major role in initiating lamellar BM damage. Aggrecanase and TIMP‐2 gene expression appear related to BM lamellar changes.

Potential relevance: MMPs, historically thought to cause laminitis, do not appear to play an initiating role in the lamellar lesion. Other host derived proteases and degradation of alternative lamellar matrix components need to be considered.
Increased plasma fructosamine concentrations in laminitic horses
Authors: KNOWLES E. J. , WITHERS J. M. , MAIR T. S.
Published: June 2011

Reasons for performing study:The use of plasma fructosamine concentration ([fructosamine]) as a marker of abnormal glucose homeostasis in laminitic horses has not been investigated.

Hypothesis:Plasma fructosamine concentration may be higher amongst laminitic horses than normal horses; this might relate to underlying insulin resistance.

Objectives:1) To compare [fructosamine] between laminitic and normal horses. 2) To investigate associations between [fructosamine] at presentation in laminitic horses with a) single sample markers of insulin resistance and b) outcome.

Methods:Plasma fructosamine concentration, fasting serum insulin concentration (insulin) and fasting plasma glucose concentration (glucose) were measured in 30 horses that presented with laminitis. Clinical details and follow‐up data were recorded. Plasma fructosamine concentration was also measured in 19 nonlaminitic control horses.

Results:Laminitic horses had significantly higher mean [fructosamine] than normal horses (P<0.001). Thirteen of 30 laminitic horses had fasting hyperinsulinaemia, 2/30 had fasting hyperglycaemia. Statistically significant univariable correlations were identified between [fructosamine] and [glucose], [insulin] and the proxies RISQI and MIRG. Trends for association between [fructosamine] and negative outcome did not reach statistical significance.

Conclusions and potential relevance:Increased mean [fructosamine] in laminitic horses may represent abnormal glycaemic control and [fructosamine] may become a clinically useful marker.
Inhibitory effects of sertraline in rat isolated perfused kidneys and in isolated ring preparations of rat arteries
Authors: Fonseca-Magalhães Patrícia A , Sousa Daniel F , de Siqueira Rodrigo J B , Jorge Roberta J B , Meneses Gdayllon C , Alves Renata S , Monteiro Helena S A , Magalhães Pedro J C , Martins Alice M C
Published: June 2011

Objectives

Sertraline is often prescribed to patients suffering with end stage renal disease, but its action on kidney has not been investigated. We aimed to investigate the pharmacological action of sertraline on rat kidney with emphasis on the underlying mechanisms involved in the vascular actions of the drug.

Methods

The effects of sertraline were evaluated in rat isolated perfused kidneys and on ring preparations of mesenteric or segmental rat renal artery.

Key findings

In kidneys, sertraline prevented the effects of phenylephrine on perfusion pressure, glomerular filtration rate, urinary flow and renal vascular resistance. In mesenteric rings sertraline inhibited phenylephrine-induced contractions with potency 30-times lower than verapamil. Sertraline reversed sustained contractions induced by phenylephrine or 60 mm K+ within a similar concentration range. In segmental isolated rings, sertraline also reversed contractions induced by phenylephrine or 60 mm K+ with the same concentration range, but with higher potency compared with mesenteric preparations. Under Ca2+-free conditions, sertraline did not change the intracellularly-mediated phasic contractions induced by phenylephrine or caffeine. Sertraline was ineffective against contractions induced by extracellular Ca2+ restoration after thapsigargin treatment and Ca2+ store depletion with phenylephrine. Conversely, sertraline decreased the contractions induced by Ca2+ addition in tissues under high K+ solution or phenylephrine plus verapamil.

Conclusions

In rat isolated kidneys and in rat ring preparations of mesenteric or renal vessels, sertraline had antispasmodic effects that appeared to be caused by a direct action on vascular smooth muscle cells. Its actions were ineffective against Ca2+-releasing intracellular pathways, but appeared to interfere with sarcolemmal Ca2+ influx with reduced permeability of both receptor- and voltage-gated Ca2+ channels.
Multisite Comparison of High-Sensitivity Multiplex Cytokine Assays
Authors: Breen Elizabeth Crabb , Reynolds Sandra M. , Cox Christopher , Jacobson Lisa P. , Magpantay Larry , Mulder Candice B. , Dibben Oliver , Margolick Joseph B. , Bream Jay H. , Sambrano Elise , Martínez-Maza Otoniel , Sinclair Elizabeth , Borrow Persephone , Landay Alan L. , Rinaldo Charles R. , Norris Philip J.
Published: June 2011

The concentrations of cytokines in human serum and plasma can provide valuable information about
in vivo
immune status, but low concentrations often require high-sensitivity assays to permit detection. The recent development of multiplex assays, which can measure multiple cytokines in one small sample, holds great promise, especially for studies in which limited volumes of stored serum or plasma are available. Four high-sensitivity cytokine multiplex assays on a Luminex (Bio-Rad, BioSource, Linco) or electrochemiluminescence (Meso Scale Discovery) platform were evaluated for their ability to detect circulating concentrations of 13 cytokines, as well as for laboratory and lot variability. Assays were performed in six different laboratories utilizing archived serum from HIV-uninfected and -infected subjects from the Multicenter AIDS Cohort Study (MACS) and the Women's Interagency HIV Study (WIHS) and commercial plasma samples spanning initial HIV viremia. In a majority of serum samples, interleukin-6 (IL-6), IL-8, IL-10, and tumor necrosis factor alpha were detectable with at least three kits, while IL-1β was clearly detected with only one kit. No single multiplex panel detected all cytokines, and there were highly significant differences (
P
< 0.001) between laboratories and/or lots with all kits. Nevertheless, the kits generally detected similar patterns of cytokine perturbation during primary HIV viremia. This multisite comparison suggests that current multiplex assays vary in their ability to measure serum and/or plasma concentrations of cytokines and may not be sufficiently reproducible for repeated determinations over a long-term study or in multiple laboratories but may be useful for longitudinal studies in which relative, rather than absolute, changes in cytokines are important.
Varicella-Zoster Virus (VZV) Glycoprotein E Is a Serological Antigen for Detection of Intrathecal Antibodies to VZV in Central Nervous System Infections, without Cross-Reaction to Herpes Simplex Virus 1
Authors: Grahn Anna , Studahl Marie , Nilsson Staffan , Thomsson Elisabeth , Bäckström Malin , Bergström Tomas
Published: June 2011

Herpes simplex virus 1 (HSV-1) and varicella-zoster virus (VZV) cause serious central nervous system (CNS) diseases that are diagnosed with PCR using samples of cerebrospinal fluid (CSF) and, during later stages of such infections, with assays of intrathecal IgG antibody production. However, serological diagnoses have been hampered by cross-reactions between HSV-1 and VZV IgG antibodies and are commonly reported in patients with herpes simplex encephalitis (HSE). In this study we have evaluated VZV glycoprotein E (gE) as a new antigen for serological diagnosis of VZV-induced CNS infections. Paired samples of CSF and serum from 29 patients with clinical diagnosis of VZV CNS infection (n= 15) or HSE (n= 14), all confirmed by PCR, were analyzed. VZV gE and whole VZV were compared as antigens in enzyme-linked immunosorbent assays (ELISAs) for serological assays in which the CSF/serum sample pairs were diluted to identical IgG concentrations. With the gE antigen, none of the HSE patients showed intrathecal IgG antibodies against VZV, compared to those shown by 11/14 patients using whole-VZV antigen (P< 0.001). In the patients with VZV infections, significantly higher CSF/serum optical density (OD) ratios were found in the VZV patients using the VZV gE antigen compared to those found using the whole-VZV antigen (P= 0.001). These results show that gE is a sensitive antigen for serological diagnosis of VZV infections in the CNS and that this antigen was devoid of cross-reactivity to HSV-1 IgG in patients with HSE. We therefore propose that VZV gE can be used for serological discrimination of CNS infections caused by VZV and HSV-1.
Sequence Analysis of the p1 Adhesin Gene of Mycoplasma pneumoniae in Clinical Isolates Collected in Beijing in 2008 to 2009
Authors: Zhao Fei , Cao Bin , Li Jing , Song Sufan , Tao Xiaoxia , Yin Yudong , He Lihua , Zhang Jianzhong
Published: June 2011

The p1 genes of 60
Mycoplasma pneumoniae
clinical isolates were sequenced and compared to previously reported p1 gene sequences. An AGT trinucleotide variable-number tandem repeat was identified that ranged in copy number from 5 to 14 among the isolates. In addition, a novel p1 gene variant named 2c was identified in 6 of the isolates.
Extensive Horizontal Gene Transfer in Ureaplasmas from Humans Questions the Utility of Serotyping for Diagnostic Purposes
Authors: Xiao Li , Paralanov Vanya , Glass John I. , Duffy Lynn B. , Robertson Janet A. , Cassell Gail H. , Chen Yuying , Waites Ken B.
Published: June 2011

Ureaplasma parvum
and
Ureaplasma urealyticum
are sexually transmitted, opportunistic pathogens of the human urogenital tract. There are 14 known serovars distributed between the two species. For decades, it has been postulated based upon limited data that virulence is related to serotype specificity. The results were often inconclusive due to the small sample size and extensive cross-reactivity between certain serovars. We developed real-time quantitative PCRs that allow reliable differentiation of the two species and type strains of each of the 14 serovars. To investigate species and serovar distributions, we typed 1,061 clinical isolates of human ureaplasmas from diverse patient populations. There was only a tenuous association between individual
Ureaplasma
serovars and certain patient populations. This may in part be explained by the fact that almost 40% of the isolates were genetic mosaics, apparently arising from the recombination of multiple serovars. This explains the extensive cross-reactivity based upon serotyping and the lack of consistent association of given serotypes with disease.
Identification of HIV Superinfection in Seroconcordant Couples in Rakai, Uganda, by Use of Next-Generation Deep Sequencing
Authors: Redd Andrew D. , Collinson-Streng Aleisha , Martens Craig , Ricklefs Stacy , Mullis Caroline E. , Manucci Jordyn , Tobian Aaron A. R. , Selig Ethan J. , Laeyendecker Oliver , Sewankambo Nelson , Gray Ronald H. , Serwadda David , Wawer Maria J. , Porcella Stephen F. , Quinn Thomas C.
Published: June 2011

HIV superinfection, which occurs when a previously infected individual acquires a new distinct HIV strain, has been described in a number of populations. Previous methods to detect superinfection have involved a combination of labor-intensive assays with various rates of success. We designed and tested a next-generation sequencing (NGS) protocol to identify HIV superinfection by targeting two regions of the HIV viral genome, p24 and gp41. The method was validated by mixing control samples infected with HIV subtype A or D at different ratios to determine the inter- and intrasubtype sensitivity by NGS. This amplicon-based NGS protocol was able to consistently identify distinct intersubtype strains at ratios of 1% and intrasubtype variants at ratios of 5%. By using stored samples from the Rakai Community Cohort Study (RCCS) in Uganda, 11 individuals who were HIV seroconcordant but virally unlinked from their spouses were then tested by this method to detect superinfection between 2002 and 2005. Two female cases of HIV intersubtype superinfection (18.2%) were identified. These results are consistent with other African studies and support the hypothesis that HIV superinfection occurs at a relatively high rate. Our results indicate that NGS can be used for detection of HIV superinfection within large cohorts, which could assist in determining the incidence and the epidemiologic, virologic, and immunological correlates of this phenomenon.
High-Resolution Genotyping of Chlamydia trachomatis by Use of a Novel Multilocus Typing DNA Microarray
Authors: Christerson Linus , Ruettger Anke , Gravningen Kirsten , Ehricht Ralf , Sachse Konrad , Herrmann Björn
Published: June 2011

Typing of
Chlamydia trachomatis
is important to understanding its epidemiology. Currently used methods such as DNA sequencing of the
ompA
gene and multilocus sequence typing (MLST) either offer limited epidemiological resolution or are laborious and expensive, or both. DNA microarray technology using the ArrayStrip format is an affordable alternative for genotyping. In this study, we developed a new multilocus typing (MLT) DNA microarray, based on the target regions of a high-resolution MLST system as well as software for easy analysis. Validation of the array was done by typing 80 previously MLST-typed clinical specimens from unselected adolescents in school. The MLT array showed 100% specificity and provided 2.4-times-higher resolution than
ompA
sequencing, separating the commonly predominating
ompA
E/Bour genotype into 7 MLT array genotypes. The MLT array reproduced epidemiological findings revealed by the MLST system and showed sufficient sensitivity to work with clinical specimens. Compared to MLST analysis, the expenses needed for testing a sample with the MLT array are considerably lower. Moreover, testing can be completed within 1 working day rather than 3 or 4 days, with data analysis not requiring highly specialized personnel. The present MLT array represents a powerful alternative in
C. trachomatis
genotyping.
Impact of Clinical Symptoms on Interpretation of Diagnostic Assays for Clostridium difficile Infections
Authors: Dubberke Erik R. , Han Zhuolin , Bobo Linda , Hink Tiffany , Lawrence Brenda , Copper Susan , Hoppe-Bauer Joan , Burnham Carey-Ann D. , Dunne William Michael
Published: June 2011

Asymptomatic
Clostridium difficile
colonization is common in hospitalized patients. Existing
C. difficile
assay comparisons lack data on severity of diarrhea or patient outcomes, limiting the ability to interpret their results in regard to the diagnosis of
C. difficile
infection (CDI). The objective of this study was to measure how including patient presentation with the
C. difficile
assay result impacted assay performance to diagnose CDI. Stool specimens from 150 patients that met inclusion and exclusion criteria were selected. Nine methods to detect
C. difficile
in stool were evaluated. All patients were interviewed prospectively to assess diarrhea severity. We then assessed how different reference standards, with and without the inclusion of patient presentation, impact the sensitivity, specificity, and positive and negative predictive values of the assays to diagnose CDI. There were minimal changes in sensitivity; however, specificity was significantly lower for the assays Tox A/B II, C. diff Chek-60, BD GeneOhm Cdiff, Xpert C. difficile, and Illumigene C. difficile and for toxigenic culture (
P
was <0.01 for all except Tox A/B II from fresh stool, for which the
P
value was 0.016) when the reference standard was recovery of toxigenic
C. difficile
from stool plus the presence of clinically significant diarrhea compared to when the reference standard was having at least four assays positive while ignoring diarrhea severity. There were 15 patients whose assay result was reported as negative but subsequently found to be positive by at least four assays in the comparison. None suffered from any CDI-related adverse events. In conclusion, clinical presentation is important when interpreting
C. difficile
diagnostic assays.
Collaborative Evaluation of an Erythromycin-Clindamycin Combination Well for Detection of Inducible Clindamycin Resistance in Beta-Hemolytic Streptococci by Use of the CLSI Broth Microdilution Method
Authors: Jorgensen James H. , McElmeel M. Leticia , Fulcher Letitia C. , McGee Lesley , Richter Sandra S. , Heilmann K. P. , Ferraro Mary Jane , Spargo Jean , Glennen Anita
Published: June 2011

Constitutive or inducible clindamycin resistance can occur in beta-hemolytic streptococci due to the presence of an
erm
gene. The Clinical and Laboratory Standards Institute (CLSI) has recommended a disk approximation test (D-zone test) with erythromycin and clindamycin disks and a single-well broth test combining erythromycin and clindamycin for detection of inducible clindamycin resistance in staphylococci, but only a disk approximation test for the beta-hemolytic streptococci. This collaborative study assessed two different erythromycin and clindamycin concentration combinations in single wells (1 μg/ml + 0.25 μg/ml [erythromycin plus clindamycin] and 1 μg/ml + 0.5 μg/ml) with three different brands of Mueller-Hinton broth supplemented with 3% lysed horse blood for testing of frozen panels prepared for this study. All labs performed the D-zone test as described by the CLSI. A total of 155 nonduplicate streptococcal isolates (50 group A, 48 group B, 28 group C, and 29 group G isolates) were tested; 99 isolates showed inducible resistance by the D-zone test. There were some differences noted based upon the test medium. The sensitivity of the erythromycin plus clindamycin combination of 1 μg/ml + 0.25 μg/ml was 91 to 100%, while the sensitivity of the combination of 1 μg/ml + 0.5 μg/ml was 95 to 100%. Specificity overall was 98%. The slightly higher sensitivity of the combination of 1 μg/ml + 0.5 μg/ml is recommended. This study has demonstrated that a single-well microdilution test incorporating erythromycin and clindamycin in combination is a sensitive and specific indicator of inducible clindamycin resistance and could be included in routine test panels.
Preanalytical Delay Reduces Sensitivity of QuantiFERON-TB Gold In-Tube Assay for Detection of Latent Tuberculosis Infection
Authors: Doberne David , Gaur Rajiv L. , Banaei Niaz
Published: June 2011

The effects of incubation delays on the accuracy of the QuantiFERON-TB gold in-tube assay (QFT-GIT) were measured. Compared to immediate incubation, 6- and 12-hour delays resulted in positive-to-negative reversion rates of 19% (5/26) and 22% (5/23), respectively. These findings underscore the need for standardizing QFT-GIT preanalytical practices.
Clinical and Microbiological Characteristics of Community-Acquired Staphylococcus lugdunensis Infections in Southern Taiwan
Authors: Wu An-Bang , Wang Ming-Cheng , Tseng Chin-Chung , Lin Wei-Hung , Teng Ching-Hao , Huang Ay-Huey , Hung Kuei-Hsiang , Chiang-Ni Chuan , Wu Jiunn-Jong
Published: June 2011

Most
Staphylococcus lugdunensis
strains (49/59, 83%) were related to clinical infections, were susceptible to most antimicrobial agents with an overall oxacillin-resistant rate of 5% (3/58), and carried relatively great genetic diversity. Community-acquired infections (41/49, 84%) were dominant, often developed in patients with comorbidity, and had rather benign clinical courses without mortality.
Inhibition of HIV-1 Tat-Mediated Transcription by a Coumarin Derivative, BPRHIV001, through the Akt Pathway
Authors: Lin Pi-Han , Ke Yi-Yu , Su Chun-Ting , Shiao Hui-Yi , Hsieh Hsing-Pang , Chao Yu-Kai , Lee Chun-Nan , Kao Chuan-Liang , Chao Yu-Sheng , Chang Sui-Yuan
Published: June 2011

The human immunodeficiency virus type 1 (HIV-1)-encoded RNA-binding protein Tat is known to play an essential role in viral gene expression. In the search for novel compounds to inhibit Tat transactivity, one coumarin derivative, BPRHIV001, was identified, with a 50% effective concentration (EC
50
) against HIV-1 at 1.3 nM. BPRHIV001 is likely to exert its effects at the stage after initiation of RNAPII elongation since Tat protein expression and the assembly of the Tat/P-TEFb complex remained unchanged. Next, a reduction of the p300 protein level, known to modulate Tat function through acetylation, was observed upon BPRHIV001 treatment, while the p300 mRNA level was unaffected. A concordant reduction of phosphorylated Akt, which was shown to be closely related to p300 stability, was observed in the presence of BPRHIV001 and was accompanied by a decrease of phosphorylated PDPK1, a well-known Akt activator. Furthermore, the docking analysis revealed that the reduced PDPK1 phosphorylation likely resulted from the allosteric effect of interaction between BPRHIV001 and PDPK1. With strong synergistic effects with current reverse transcriptase inhibitors, BPRHIV001 has the potential to become a promising lead compound for the development of a novel therapeutic agent against HIV-1 infection.
The Ribonucleotide Reductase R1 Subunits of Herpes Simplex Virus 1 and 2 Protect Cells against Poly(I · C)-Induced Apoptosis
Authors: Dufour Florent , Bertrand Luc , Pearson Angela , Grandvaux Nathalie , Langelier Yves
Published: June 2011

We recently provided evidence that the ribonucleotide reductase R1 subunits of herpes simplex virus types 1 and 2 (HSV-1 and -2) protect cells against tumor necrosis factor alpha- and Fas ligand-induced apoptosis by interacting with caspase 8. Double-stranded RNA (dsRNA) is a viral intermediate known to initiate innate antiviral responses. Poly(I · C), a synthetic analogue of viral dsRNA, rapidly triggers caspase 8 activation and apoptosis in HeLa cells. Here, we report that HeLa cells after HSV-1 and HSV-2 infection were quickly protected from apoptosis caused by either extracellular poly(I · C) combined with cycloheximide or transfected poly(I · C). Cells infected with the HSV-1 R1 deletion mutant ICP6Δ were killed by poly(I · C), indicating that HSV-1 R1 plays a key role in antiapoptotic responses to poly(I · C). Individually expressed HSV R1s counteracted caspase 8 activation by poly(I · C). In addition to their binding to caspase 8, HSV R1s also interacted constitutively with receptor-interacting protein 1 (RIP1) when expressed either individually or with other viral proteins during HSV infection. R1(1-834)-green fluorescent protein (GFP), an HSV-2 R1 deletion mutant protein devoid of antiapoptotic activity, did not interact with caspase 8 and RIP1, suggesting that these interactions are required for protection against poly(I · C). HSV-2 R1 inhibited the interaction between the Toll/interleukin-1 receptor domain-containing adaptor-inducing beta interferon (IFN-β) (TRIF) and RIP1, an interaction that is essential for apoptosis triggered by extracellular poly(I · C) plus cycloheximide or TRIF overexpression. TRIF silencing reduced poly(I · C)-triggered caspase 8 activation in mock- and ICP6Δ-infected cells, confirming that TRIF is involved in poly(I · C)-induced apoptosis. Thus, by interacting with caspase 8 and RIP1, HSV R1s impair the apoptotic host defense mechanism prompted by dsRNA.
Cleavage of the Adaptor Protein TRIF by Enterovirus 71 3C Inhibits Antiviral Responses Mediated by Toll-Like Receptor 3
Authors: Lei Xiaobo , Sun Zhenmin , Liu Xinlei , Jin Qi , He Bin , Wang Jianwei
Published: June 2011

Enterovirus 71 (EV71) causes hand-foot-and-mouth disease and neurological complications in young children. Although the underlying mechanisms remain obscure, impaired or aberrant immunity is thought to play a role. In infected cells, EV71 suppresses type I interferon responses mediated by retinoid acid-inducible gene I (RIG-I). This involves the EV71 3C protein, which disrupts the formation of a functional RIG-I complex. In the present study, we report that EV71 inhibits the induction of innate immunity by Toll-like receptor 3 (TLR3) via a distinct mechanism. In HeLa cells stimulated with poly(I · C), EV71 inactivates interferon regulatory factor 3 and drastically suppresses interferon-stimulated gene expression. Notably, EV71 specifically downregulates a TRIF, TIR domain-containing adaptor inducing beta interferon (IFN-β). When expressed alone in mammalian cells, EV71 3C is capable of exhibiting these activities. EV71 3C associates with and induces TRIF cleavage in the presence of Z-VAD-FMK, a caspase inhibitor. TRIF cleavage depends on its amino acid pair Q312-S313, which resembles a proteolytic site of picornavirus 3C proteases. Further, site-specific 3C mutants with a defective protease activity bind TRIF but fail to mediate TRIF cleavage. Consequently, these 3C mutants are unable to inhibit NF-κB and IFN-β promoter activation. TRIF cleavage mediated by EV71 may be a mechanism to impair type I IFN production in response to Toll-like receptor 3 (TLR3) activation.
Cellular Transcription Factor Oct-1 Interacts with the Epstein-Barr Virus BRLF1 Protein To Promote Disruption of Viral Latency
Authors: Robinson Amanda R. , Kwek Swee Sen , Hagemeier Stacy R. , Wille Coral K. , Kenney Shannon C.
Published: June 2011

The Epstein-Barr virus (EBV) latent-to-lytic switch is an essential part of the viral life cycle, but the cellular factors that promote viral reactivation are not well defined. In this report, we demonstrate that the cellular transcription factor Oct-1 cooperates with the EBV immediate-early protein BRLF1 (R, Rta) to induce lytic viral reactivation. We show that cotransfected Oct-1 enhances the ability of BRLF1 to activate lytic gene expression in 293 cells stably infected with a BRLF1-defective EBV mutant (BRLF1-stop) and that Oct-1 increases BRLF1-mediated activation of lytic EBV promoters in reporter gene assays. We find that Oct-1 interacts directly with BRLF1
in vitro
and that a mutant BRLF1 protein (the M140A mutant) attenuated for the ability to interact with Oct-1
in vitro
is also resistant to Oct-1-mediated transcriptional enhancement in 293 BRLF1-stop cells. Furthermore, we show that cotransfected Oct-1 augments BRLF1 binding to a variety of lytic EBV promoters in chromatin immunoprecipitation (ChIP) assays (including the BZLF1, BMRF1, and SM promoters) and that BRLF1 tethers Oct-1 to lytic EBV promoters. In addition, we demonstrate that an Oct-1 mutant defective in DNA binding (the S335D mutant) still retains the ability to enhance BRLF1 transcriptional effects. Finally, we show that knockdown of endogenous Oct-1 expression reduces the level of constitutive lytic EBV gene expression in both EBV-positive B-cell and EBV-positive epithelial cell lines. These results suggest that Oct-1 acts as a positive regulator of EBV lytic gene expression and that this effect is at least partially mediated through its interaction with the viral protein BRLF1.
In Vivo
Comparison of Chronic Wasting Disease Infectivity from Deer with Variation at Prion Protein Residue 96
Authors: Race Brent , Meade-White Kimberly , Miller Michael W. , Fox Karen A. , Chesebro Bruce
Published: June 2011

Chronic wasting disease (CWD) is a prion disease of cervids that causes neurodegeneration and death. Susceptibility to prion infections, including CWD, can be dependent on the amino acid sequence of the host prion protein (PrP). Here, CWD agent obtained from a deer expressing the 96SS genotype, associated with partial resistance to CWD, was used to infect transgenic (tg) mice expressing either 96GG or 96SS deer PrP. Transgenic mice expressing 96GG deer PrP succumbed to this agent, but tg mice expressing 96SS deer PrP did not. Additional studies using inocula from 96GG deer showed no transmission to 96SS PrP mice and delayed disease in 96GS mice. Thus, 96S PrP played an inhibitory role in disease progression in tg mice.
Poliovirus Switches to an eIF2-Independent Mode of Translation during Infection
Authors: White James P. , Reineke Lucas C. , Lloyd Richard E.
Published: June 2011

Inhibition of translation is an integral component of the innate antiviral response and is largely accomplished via interferon-activated phosphorylation of the α subunit of eukaryotic initiation factor 2 (eIF2α). To successfully infect a host, a virus must overcome this blockage by either controlling eIF2α phosphorylation or by utilizing a noncanonical mode of translation initiation. Here we show that enterovirus RNA is sensitive to translation inhibition resulting from eIF2α phosphorylation, but it becomes resistant as infection progresses. Further, we show that the cleavage of initiation factor eIF5B during enteroviral infection, along with the viral internal ribosome entry site, plays a role in mediating viral translation under conditions that are nonpermissive for host cell translation. Together, these results provide a mechanism by which enteroviruses evade the antiviral response and provide insight into a noncanonical mechanism of translation initiation.
Effective Antiviral Treatment of Systemic Orthopoxvirus Disease: ST-246 Treatment of Prairie Dogs Infected with Monkeypox Virus
Authors: Smith Scott K. , Self Josh , Weiss Sonja , Carroll Darin , Braden Zach , Regnery Russell L. , Davidson Whitni , Jordan Robert , Hruby Dennis E. , Damon Inger K.
Published: June 2011

Smallpox preparedness research has led to development of antiviral therapies for treatment of serious orthopoxvirus infections. Monkeypox virus is an emerging, zoonotic orthopoxvirus which can cause severe and transmissible disease in humans, generating concerns for public health. Monkeypox virus infection results in a systemic, febrile-rash illness closely resembling smallpox. Currently, there are no small-molecule antiviral therapeutics approved to treat orthopoxvirus infections of humans. The prairie dog, using monkeypox virus as a challenge virus, has provided a valuable nonhuman animal model in which monkeypox virus infection closely resembles human systemic orthopoxvirus illness. Here, we assess the efficacy of the antiorthopoxvirus compound ST-246 in prairie dogs against a monkeypox virus challenge of 65 times the 50% lethal dose (LD50). Animals were infected intranasally and administered ST-246 for 14 days, beginning on days 0, 3, or after rash onset. Swab and blood samples were collected every 2 days and analyzed for presence of viral DNA by real-time PCR and for viable virus by tissue culture. Seventy-five percent of infected animals that received vehicle alone succumbed to infection. One hundred percent of animals that received ST-246 survived challenge, and animals that received treatment before symptom onset remained largely asymptomatic. Viable virus and viral DNA were undetected or at greatly reduced levels in animals that began treatment on 0 or 3 days postinfection, compared to control animals or animals treated post-rash onset. Animals treated after rash onset manifested illness, but all recovered. Our results indicate that ST-246 can be used therapeutically, following onset of rash illness, to treat systemic orthopoxvirus infections.
Cutaneous Human Papillomavirus Type 38 E7 Regulates Actin Cytoskeleton Structure for Increasing Cell Proliferation through CK2 and the Eukaryotic Elongation Factor 1A
Authors: Yue Jiping , Shukla Ruchi , Accardi Rosita , Zanella-Cleon Isabelle , Siouda Maha , Cros Marie-Pierre , Krutovskikh Vladimir , Hussain Ishraq , Niu Yamei , Hu Shiqiong , Becchi Michel , Jurdic Pierre , Tommasino Massimo , Sylla Bakary S.
Published: June 2011

We previously reported that the oncoproteins E6 and E7 from cutaneous human papillomavirus type 38 (HPV38) can immortalize primary human keratinocytes
in vitro
and sensitize transgenic mice to develop skin cancer
in vivo
. Immunofluorescence staining revealed that human keratinocytes immortalized by HPV38 E6 and E7 display fewer actin stress fibers than do control primary keratinocyte cells, raising the possibility of a role of the viral oncoproteins in the remodeling of the actin cytoskeleton. In this study, we show that HPV38 E7 induces actin stress fiber disruption and that this phenomenon correlates with its ability to downregulate Rho activity. The downregulation of Rho activity by HPV38 E7 is mediated through the activation of the CK2–MEK–extracellular signal-regulated kinase (ERK) pathway. In addition, HPV38 E7 is able to induce actin fiber disruption by binding directly to eukaryotic elongation factor 1A (eEF1A) and abolishing its effects on actin fiber formation. Finally, we found that the downregulation of Rho activity by HPV38 E7 through the CK2-MEK-ERK pathway facilitates cell growth proliferation. Taken together, our data support the conclusion that HPV38 E7 promotes keratinocyte proliferation in part by negatively regulating actin cytoskeleton fiber formation through the CK2-MEK-ERK-Rho pathway and by binding to eEF1A and inhibiting its effects on actin cytoskeleton remodeling.
Ebolavirus Δ-Peptide Immunoadhesins Inhibit Marburgvirus and Ebolavirus Cell Entry
Authors: Radoshitzky Sheli R. , Warfield Kelly L. , Chi Xiaoli , Dong Lian , Kota Krishna , Bradfute Steven B. , Gearhart Jacqueline D. , Retterer Cary , Kranzusch Philip J. , Misasi John N. , Hogenbirk Marc A. , Wahl-Jensen Victoria , Volchkov Viktor E. , Cunningham James M. , Jahrling Peter B. , Aman M. Javad , Bavari Sina , Farzan Michael , Kuhn Jens H.
Published: June 2011

With the exception of Reston and Lloviu viruses, filoviruses (marburgviruses, ebolaviruses, and “cuevaviruses”) cause severe viral hemorrhagic fevers in humans. Filoviruses use a class I fusion protein, GP
1,2
, to bind to an unknown, but shared, cell surface receptor to initiate virus-cell fusion. In addition to GP
1,2
, ebolaviruses and cuevaviruses, but not marburgviruses, express two secreted glycoproteins, soluble GP (sGP) and small soluble GP (ssGP). All three glycoproteins have identical N termini that include the receptor-binding region (RBR) but differ in their C termini. We evaluated the effect of the secreted ebolavirus glycoproteins on marburgvirus and ebolavirus cell entry, using Fc-tagged recombinant proteins. Neither sGP-Fc nor ssGP-Fc bound to filovirus-permissive cells or inhibited GP
1,2
-mediated cell entry of pseudotyped retroviruses. Surprisingly, several Fc-tagged Δ-peptides, which are small C-terminal cleavage products of sGP secreted by ebolavirus-infected cells, inhibited entry of retroviruses pseudotyped with Marburg virus GP
1,2
, as well as Marburg virus and Ebola virus infection in a dose-dependent manner and at low molarity despite absence of sequence similarity to filovirus RBRs. Fc-tagged Δ-peptides from three ebolaviruses (Ebola virus, Sudan virus, and Taï Forest virus) inhibited GP
1,2
-mediated entry and infection of viruses comparably to or better than the Fc-tagged RBRs, whereas the Δ-peptide-Fc of an ebolavirus nonpathogenic for humans (Reston virus) and that of an ebolavirus with lower lethality for humans (Bundibugyo virus) had little effect. These data indicate that Δ-peptides are functional components of ebolavirus proteomes. They join cathepsins and integrins as novel modulators of filovirus cell entry, might play important roles in pathogenesis, and could be exploited for the synthesis of powerful new antivirals.
Binding of the Mannose-Specific Lectin, Griffithsin, to HIV-1 gp120 Exposes the CD4-Binding Site
Authors: Alexandre Kabamba Bankoledi , Gray Elin S. , Pantophlet Ralph , Moore Penny L. , McMahon James B. , Chakauya Ereck , O'Keefe Barry R. , Chikwamba Rachel , Morris Lynn
Published: June 2011

The glycans on HIV-1 gp120 play an important role in shielding neutralization-sensitive epitopes from antibody recognition. They also serve as targets for lectins that bind mannose-rich glycans. In this study, we investigated the interaction of the lectin griffithsin (GRFT) with HIV-1 gp120 and its effects on exposure of the CD4-binding site (CD4bs). We found that GRFT enhanced the binding of HIV-1 to plates coated with anti-CD4bs antibodies b12 and b6 or the CD4 receptor mimetic CD4-IgG2. The average enhancement of b12 or b6 binding was higher for subtype B viruses than for subtype C, while for CD4-IgG2, it was similar for both subtypes, although lower than observed with antibodies. This GRFT-mediated enhancement of HIV-1 binding to b12 was reflected in synergistic neutralization for 2 of the 4 viruses tested. The glycan at position 386, which shields the CD4bs, was involved in both GRFT-mediated enhancement of binding and neutralization synergism between GRFT and b12. Although GRFT enhanced CD4bs exposure, it simultaneously inhibited ligand binding to the coreceptor binding site, suggesting that GRFT-dependent enhancement and neutralization utilize independent mechanisms. This study shows for the first time that GRFT interaction with gp120 exposes the CD4bs through binding the glycan at position 386, which may have implications for how to access this conserved site.
Mutational Analysis of the Zippering Reaction during Flavivirus Membrane Fusion
Authors: Pangerl Karen , Heinz Franz X. , Stiasny Karin
Published: June 2011

The current model of flavivirus membrane fusion is based on atomic structures of truncated forms of the viral fusion protein E in its dimeric prefusion and trimeric postfusion conformations. These structures lack the two transmembrane domains (TMDs) of E as well as the so-called stem, believed to be involved in an intra- and intermolecular zippering reaction within the E trimer during the fusion process. In order to gain experimental evidence for the functional role of the stem in flavivirus membrane fusion, we performed a mutagenesis study with recombinant subviral particles (RSPs) of tick-borne encephalitis virus, which have fusion properties similar to those of whole infectious virions and are an established model for viral fusion. Mutations were introduced into the stem as well as that part of E predicted to interact with the stem during zippering, and the effect of these mutations was analyzed with respect to fusion peptide interactions with target cells, E protein trimerization, trimer stability, and membrane fusion in an
in vitro
liposome fusion assay. Our data provide evidence for a molecular interaction between a conserved phenylalanine at the N-terminal end of the stem and a pocket in domain II of E, which appears to be essential for the positioning of the stem in an orientation that allows zippering and the formation of a structure in which the TMDs can interact as required for efficient fusion.
Current practice patterns among pathologists in the assessment of venous invasion in colorectal cancer
Authors: Messenger David E , Driman David K , McLeod Robin S , Riddell Robert H , Kirsch Richard
Published: June 2011

Aims

Venous invasion (VI) is a known independent prognostic indicator of recurrence and survival in colorectal cancer. The guidelines of the Royal College of Pathologists (RCPath) state that, in a series of resections, extramural VI should be detected in at least 25% of specimens. However, there is widespread variability in the reported incidence, and this may affect patient access to adjuvant therapy. This study aims to clarify the current practice patterns of pathologists regarding the assessment of VI and to identify factors associated with an increased self-reported VI detection rate.

Methods

A population-based survey was mailed to 361 pathologists in the province of Ontario, Canada.

Results

The overall response rate was 64.9%. Most pathologists were practicing in community-based centres (66.2%) and approximately half had been in practice for over 15 years (53.5%). A subspecialist interest in gastrointestinal (GI) pathology was declared by 27.3% of pathologists. The majority of pathologists (70.2%) reported that they detected VI in less than 10% of resection specimens, with only 9.1% reporting VI detection rates above 20%. Standardised reporting criteria were applied by 62.1%. Special stains were employed by 57.6% if VI was suspected on H&E-stained sections. Practice in a university-affiliated centre, a subspecialist interest in GI pathology and the acceptance of the ‘orphan arteriole’ sign were all independently associated with a self-reported VI detection rate above 10% on multivariate analysis.

Conclusions

Self-reported VI detection rates are low among most pathologists. Even among specialist GI pathologists practicing in university-affiliated centres, few reported a detection rate close to that recommended by the RCPath. Strategies to increase the detection of VI may be required.
AUTOMATIC PORTAL GENERATION BASED ON WORKFLOW DESCRIPTION
Authors: WALKER CORAL , LU DASHAN , WALKER DAVID W.
Published: June 2011

Distributed scientific and engineering computations on service-oriented architectures are often represented as data-driven workflows. Workflows are a convenient abstraction that allows users to compose applications in a visual programming environment, and execute them by means of a workflow execution engine. For a large class of scientific applications web-based portals can provide a user-friendly problem-solving environment that hides the complexities of executing workflow applications in a distributed environment. However, the creation and configuration of an application portal requires considerable expertise in portal technologies, which scientific end-users generally do not have. To address this problem this paper presents tools for automatically converting a workflow into a fully configured portal which can then be used to execute the workflow.
HIGH PERFORMANCE AND SCALABLE RADIX SORTING: A CASE STUDY OF IMPLEMENTING DYNAMIC PARALLELISM FOR GPU COMPUTING
Authors: MERRILL DUANE , GRIMSHAW ANDREW
Published: June 2011

The need to rank and order data is pervasive, and many algorithms are fundamentally dependent upon sorting and partitioning operations. Prior to this work, GPU stream processors have been perceived as challenging targets for problems with dynamic and global data-dependences such as sorting. This paper presents: (1) a family of very efficient parallel algorithms for radix sorting; and (2) our allocation-oriented algorithmic design strategies that match the strengths of GPU processor architecture to this genre of dynamic parallelism. We demonstrate multiple factors of speedup (up to 3.8x) compared to state-of-the-art GPU sorting. We also reverse the performance differentials observed between GPU and multi/many-core CPU architectures by recent comparisons in the literature, including those with 32-core CPU-based accelerators. Our average sorting rates exceed 1B 32-bit keys/sec on a single GPU microprocessor. Our sorting passes are constructed from a very efficient parallel prefix scan "runtime" that incorporates three design features: (1) kernel fusion for locally generating and consuming prefix scan data; (2) multi-scan for performing multiple related, concurrent prefix scans (one for each partitioning bin); and (3) flexible algorithm serialization for avoiding unnecessary synchronization and communication within algorithmic phases, allowing us to construct a single implementation that scales well across all generations and configurations of programmable NVIDIA GPUs.
SAFETY ASSESSMENT FOR SAFETY-CRITICAL SYSTEMS USING MARKOV CHAIN MODULAR APPROACH
Authors: YU YANGYANG , JOHNSON BARRY W.
Published: June 2011

The Markov Chain Modular (MCM) approach is proposed in this paper in order to solve part of the failure-state dependency problem. The MCM approach completely avoids the failure-state dependency problem by avoiding the combinatorial modeling. To quantitatively assess safety, a new Markov chain modeling technique is developed to represent an m + 2 state homogenous Markov chain model using a three-state Markov model. The transition rate functions of the three-state Markov model can be determined by the transition rates of the m + 2 state Markov chain model. Given a series system has N modules and each module has O(m) operational states, the MCM approach reduces the operational states to O(N × m2) as opposed to O(m2N) by using the traditional Markov chain model.
High Purity GaAs Crystals Grown by Liquid Phase Epitaxy
Authors: Miki Hidejiro , Otsubo Mutsuyuki
Published: June 2011

Hidejiro Miki and Mutsuyuki Otsubo
Simulation of X-Ray Mask Repair by Means of FIB-Technology
Authors: Müller Karl Paul
Published: June 2011

The received date of this paper should be corrected as follows: (Received July 5, 1989; accepted for publication August 19, 1989)
Optical and Electrical Properties of p-GaAe Doped with Sb
Authors: Shigetomi Shigeru , Ikari Tetsuo , Nishimura Hideki
Published: June 2011

The sample name in title was mistakenly printed. “GaAe” should read “GaSe”.
Deposition of Heteroepitaxial In2O3Thin Films by Molecular Beam Epitaxy
Authors: Taga Naoaki , Maekawa Mikako , Shigesato Yuzo , Yasui Itaru , Kakei Masayuki , Haynes T. E.
Published: June 2011

One of the authors' name “Masayuki Kakei” should read “Masayuki Kamei”.
Effect of pulmonary TNF-α overexpression on mouse isolated skeletal muscle function
Authors: Zuo Li , Nogueira Leonardo , Hogan Michael C.
Published: June 2011

TNF-α is a proinflammatory cytokine that is involved in numerous pathological processes including chronic obstructive pulmonary disease (COPD). In the present study, we used a transgenic mouse model that overexpresses TNF-α in the lung (Tg+) to test the hypothesis that chronic exposure to TNF-α (as seen in COPD) reduces skeletal muscle force production and fatigue resistance, particularly under low Po2 conditions. At 7–12 mo, body and muscle weight of both extensor digitorum longus (EDL) and soleus were significantly smaller in Tg+ compared with littermate wild-type (WT) mice; however, the body-to-muscle weight ratio was not different between groups. EDL and soleus muscles were subjected to in vitro fatiguing contractile periods under high (∼550 Torr) and low Po2 (∼40 Torr). Although all muscles were less fatigue-resistant during low Po2 compared with high Po2, only the soleus fatigued more rapidly in Tg+ mice (∼12%) compared with WT at high Po2. The maximal tension of EDL was equally reduced in Tg+ mice (28–34% decrease from WT under both Po2 conditions); but for soleus this parameter was smaller only under low Po2 in Tg+ mice (∼31% decrease from WT). The peak rate of relaxation and the peak rate of contraction were both significantly reduced in Tg+ EDL muscles compared with WT EDL under low Po2 conditions, but not in soleus. These results demonstrate that TNF-α upregulation in the lung impairs peripheral skeletal muscle function but affects fast- and slow-twitch muscles differentially at high and low Po2.