bluuebunny/crossref_metadata_2025 huggingface dataset:
Accumulation of oxidized peroxiredoxin 2 in red blood cells and its prevention
Authors: Bayer Simone B. , Hampton Mark B. , Winterbourn Christine C.
Published: February 2015

Background

The thiol protein peroxiredoxin 2 (Prx2) is a major red blood cell (RBC) antioxidant that breaks down hydroperoxides and in the process is converted to an oxidized disulfide. Our objective was to determine whether Prx2 becomes oxidized during storage of RBCs, to understand the underlying mechanism, and to find ways of preventing the accumulation of the oxidized form.

Study design and Methods

RBCs were stored for up to 6 weeks under simulated blood banking conditions and Prx2 oxidation was monitored by nonreducing gel electrophoresis. The ability of the cells to reverse Prx2 oxidation after storage and to respond to added hydrogen peroxide was also evaluated.

Results

Prx2 remained predominantly reduced during the first 3 weeks of storage, and then the oxidized form accumulated progressively. In contrast to fresh cells, oxidation was not reversed by incubation with glucose. Storage of RBCs in a high‐pH, low‐chloride, and high‐phosphate/bicarbonate buffer (EAS‐76v6) largely prevented accumulation of oxidized Prx for at least 6 weeks, and dihydrolipoic acid (DHLA), but not Rejuvesol, N‐acetylcysteine, or α‐lipoic acid, was able to reverse or protect against Prx2 oxidation. Additional, Prx2 oxidation occurred when hydrogen peroxide was added. However, this was reversible, suggesting that the reductive capacity was compromised in some but not in all cells.

Conclusion

Prx2 remains mostly reduced in a high‐pH storage solution with buffering capacity. Addition of DHLA to stored RBCs might be advantageous. Prx2 redox status could be used as a biomarker for the quality of stored RBCs.
Bitten by a bug or a bag? Transfusion‐transmitted dengue: a rare complication in the bleeding surgical patient
Authors: Oh Han Boon , Muthu Vaishnavi , Daruwalla Zubin J. , Lee Shir Ying , Koay Evelyn S. , Tambyah Paul A.
Published: February 2015

BACKGROUND

Blood‐borne infections remain a risk of blood transfusions. While routine screening of donated blood products has greatly reduced the risk of human immunodeficiency virus, hepatitis B, and hepatitis C transmission, arboviruses such as dengue, chikungunya, and the West Nile virus remain significant risks especially during outbreaks.

CASE REPORT

We report a rare case of dengue documented to be acquired through a blood transfusion, which resulted in severe thrombocytopenia prolonging admission in hospital in a neurosurgical patient.

RESULTS

The donor of one of the units of red blood cells presented with dengue fever 2 days after donating. Sanger sequencing confirmed DENV‐2 (dengue virus, Serotype 2) in both the donor and the patient samples and showed 100% nucleotide sequence identity between the two viruses, confirming transfusion‐transmitted dengue infection.

CONCLUSION

This case highlights the importance of arboviral screening of donor blood, especially for populations in endemic areas during outbreaks.
Plerixafor on demand in ten healthy family donors as a rescue strategy to achieve an adequate graft for stem cell transplantation
Authors: Gattillo Salvatore , Marktel Sarah , Rizzo Lorenzo , Malato Simona , Malabarba Lucia , Coppola Milena , Assanelli Andrea , Milani Raffaella , De Freitas Tiago , Corti Consuelo , Bellio Laura , Ciceri Fabio
Published: February 2015

BACKGROUND

In allogeneic hematopoietic stem cell (HSC) transplantation, the collection of an appropriate number of HSCs while maintaining a high level of safety for healthy donors is fundamental. Inadequate HSC mobilization can be seen with the standard use of granulocyte–colony‐stimulating (G‐CSF). Plerixafor (PL) is a chemokine receptor CXC Type 4–stromal‐derived factor 1 inhibitor; its HSC‐mobilizing properties are synergistic with G‐CSF in poor mobilizing patients. The use of PL as adjuvant or alternative to G‐CSF in healthy donors has shown a good safety profile but is so far off‐label.

STUDY DESIGN AND METHODS

We report 10 healthy HSC donors treated with PL because of insufficient response to G‐CSF alone or contraindication to G‐CSF. Eight donors did not mobilize enough CD34+ cells with G‐CSF alone because poor mobilizers or because insufficient HSCs were harvested according to the clinical need of the patient; in two cases G‐CSF administration and marrow harvest were unfeasible or contraindicated in the donor.

RESULTS

The use of PL for mobilization increased the number of circulating CD34+ cells by 2.8‐fold and the CD34+/kg collection by 3.0‐fold. Only mild adverse events were reported (bone pain or discomfort) and not univocally attributable to PL. Rate of engraftment and graft‐versus‐host disease were similar to those seen in recipients of grafts from G‐CSF only–mobilized donors.

CONCLUSION

We exposed 10 allogeneic donors to mobilization with PL. PL was well tolerated in all cases and ensured procurement of an adequate graft for transplantation resulting in a normal hematopoietic engraftment.
The preanalytic phase in veterinary clinical pathology
Authors: Braun Jean‐Pierre , Bourgès‐Abella Nathalie , Geffré Anne , Concordet Didier , Trumel Cathy
Published: February 2015

This article presents the general causes of preanalytic variability with a few examples showing specialists and practitioners that special and improved care should be given to this too often neglected phase. The preanalytic phase of clinical pathology includes all the steps from specimen collection to analysis. It is the phase where most laboratory errors occur in human, and probably also in veterinary clinical pathology. Numerous causes may affect the validity of the results, including technical factors, such as the choice of anticoagulant, the blood vessel sampled, and the duration and conditions of specimen handling. While the latter factors can be defined, influence of biologic and physiologic factors such as feeding and fasting, stress, and biologic and endocrine rhythms can often not be controlled. Nevertheless, as many factors as possible should at least be documented. The importance of the preanalytic phase is often not given the necessary attention, although the validity of the results and consequent clinical decision making and medical management of animal patients would likely be improved if the quality of specimens submitted to the laboratory was optimized.
Dynamic exophthalmos and lateral strabismus in a dog caused by masticatory muscle myositis
Authors: Czerwinski Sarah L. , Plummer Caryn E. , Greenberg Shari M. , Craft William F. , Conway Julia A. , Perez Mayrim L. , Cooke Kirsten L. , Winter Matthew D.
Published: February 2015

Case description

A 5.5‐year‐old neutered male mixed‐breed dog was presented for evaluation of a 5‐month history of deviation of the right globe upon opening the mouth and a 1‐month history of conjunctivitis in the same eye. Clinical findings, diagnostic imaging results, treatment and follow‐up are described.

Clinical findings

When the mouth was opened, the right globe deviated rostrally and laterally. There was no pain or resistance to opening the mouth, or resistance to retropulsion of the globe. No other abnormalities were observed. Computed tomography was performed, revealing a contrast‐enhancing region associated with the right masseter muscle impinging into the right orbit; this was more pronounced with the mouth open. Cytology revealed a small number of mildly to moderately atypical mesenchymal cells. Histopathology was consistent with polyphasic myositis, with a predominance of lymphocytes and plasma cells. No infectious agents were identified. Serum antibody titers forToxoplasma gondiiandNeospora caninumwere negative. Serum titers for 2 M antibody were positive at 1:500, consistent with a diagnosis of masticatory muscle myositis.

Treatment and outcome

Therapy with prednisone was initiated. During a follow‐up period of 5 months, there was no recurrence of clinical signs, and the dose of prednisone was reduced by 25%.

Clinical significance

To the authors' knowledge, this is the first reported case of masticatory muscle myositis causing dynamic exophthalmos and strabismus in a dog.
The effect of metabolic alkalosis on central and peripheral mechanisms associated with exercise‐induced muscle fatigue in humans
Authors: Siegler Jason C. , Marshall Paul
Published: February 2015

New Findings

What is the central question of this study?

Does metabolic alkalosis affect central and peripheral mechanisms associated with exercise‐induced muscle fatigue in humans?

What is the main finding and its importance?

Inducing metabolic alkalosis before exercise preserved voluntary activation, but not muscle excitation, after a 2 min maximal voluntary contraction (MVC) followed by ischaemia. An effect of pH was also observed in maximal rates of torque development, where alkalosis mitigated the reduction in maximal rates of torque development after the initial 2 min MVC. For the first time, these results demonstrate a differential effect of pH on voluntary activation as well as maximal rates of torque development after sustained, maximal voluntary knee extension in humans.

The increased concentration of protons during fatiguing exercise may contribute to increased activation of group III and IV afferents and subsequently reduced central drive, but this has yet to be confirmed in exercising humans. Here, we determined whether inducing metabolic alkalosis differentially affects descending central drive after fatiguing exercise and whether this effect may, in part, be explained by attenuating group III and IV afferent firing. Eleven men performed a maximal 2 min voluntary knee extension (MVC) followed by a 2 min rest and subsequent 1 min MVC with an occlusive cuff either in placebo [PLA; 0.3 g (kg body weight)−1 calcium carbonate] or alkalosis conditions [ALK; 0.3 g (kg body weight)−1 sodium bicarbonate]. Femoral nerve stimulation was applied before exercise, after the 2 min MVC and at 40–60 s intervals throughout the remainder of the protocol to explore central and peripheral mechanisms associated with reductions in maximal force and rate of torque development. Although voluntary activation declined to a similar extent after the 2 min MVC, during the ischaemic period voluntary activation was higher during ALK (PLA, 57 ± 8%; ALK, 76 ± 5%). Maximal voluntary torque declined at similar rates during the task (203 ± 19 N m), but maximal rate of torque development was significantly higher in the ALK conditions after the 2 min MVC (mean difference of 177 ± 60 N m s−1). These results demonstrate the effect of pH on voluntary activation as well as maximal rates of torque development after sustained, maximal voluntary knee extension in humans.
Field emission beam characteristics of single metal nanotip cathodes with on-chip collimation gate electrode
Authors: Lee Chiwon , Kanungo Pratyush Das , Guzenko Vitaliy , Hefenstein Patrick , Miller R. J. Dwayne , Tsujino Soichiro
Published: February 2015

Field-emission and beam collimation characteristics of single metal nanotip devices with double-gate electrodes are studied. Applying a previously developed method to fabricate all-metal double-gate nanotip arrays with a stacked on-chip extraction Gext and collimation Gcol gate electrodes with the large Gcol apertures, the authors produced single double-gate nanotip devices and measured their beam characteristics. Excellent beam collimation capability with minimal reduction of the emission current and the enhancements of the current density up to a factor of ∼7 was observed. The results indicate that these single nanotip devices are highly promising for electron beam applications that require extremely high brilliance and coherence.
Narratives of Britishness and Team GB in the National Newspaper of Wales
Authors: Harris John , Vincent John
Published: February 2015

The spectacular success of Team GB in the London 2012 Olympic Games saw an extension of a popular celebration of Britishness. Drawing on an analysis of Olympic coverage in the Western Mail, self-styled national newspaper of Wales (papur cenedlaethol Cymru), this study explores the ways in which narratives of the nation are (re)presented in a particular locale. After a brief discussion of the opening ceremony, key events from the Games, including the staging of football matches in the capital city of Cardiff, the singing of “God Save the Queen” before football matches, and the medal successes of Welsh athletes, are used as cases to explore the multiple layers of national identities at play. The analysis highlights the complementary, complex, and at times contradictory interplay between Welsh and British identities within these narratives and explores the often fuzzy and sometimes hazy frontiers of identity.
A biosensor for the activity of the “sheddase” TACE (ADAM17) reveals novel and cell type–specific mechanisms of TACE activation
Authors: Chapnick Douglas A. , Bunker Eric , Liu Xuedong
Published: February 2015

A FRET-based sensor reports the spatiotemporal dynamics of the protease TACE in live cells.
An interaction that guides cell fate
Authors: Vinson Valda
Published: February 2015

O-linked glycosylation regulates a receptor-ligand interaction that is important in cell fate determination.
Inflammation resolution: A solution for advanced atherosclerosis
Authors: Frisk Megan L.
Published: February 2015

Nanoparticles containing an annexin-derived peptide activate the annexin A1 receptor on myeloid cells to promote resolution of inflammation in atherosclerosis.
Nitrogen stress activates AMPK
Authors: VanHook Annalisa M.
Published: February 2015

AMPK inhibits TORC1 signaling in response to nitrogen stress.
Changing progeny’s inheritance
Authors: Gough Nancy R.
Published: February 2015

Double-stranded RNA in neurons can alter gene expression in progeny of nematodes.
Tuberculosis vaccines: Time for a global strategy
Authors: Kaufmann Stefan H. E. , Evans Thomas G. , Hanekom Willem A.
Published: February 2015

We need a global strategy for the development of better tuberculosis vaccines.
Seq and the city
Authors: Tsalik Ephraim L.
Published: February 2015

City-scale metagenomics reveal who we are and the dynamic environment we live in.
In Vivo
Activities of Simulated Human Doses of Cefepime and Cefepime-AAI101 against Multidrug-Resistant Gram-Negative Enterobacteriaceae
Authors: Crandon Jared L. , Nicolau David P.
Published: February 2015

The combination of cefepime with AAI101, a novel extended-spectrum β-lactamase inhibitor, possesses potent
in vitro
activity against many resistant Gram-negative pathogens. Against a panel of 20 mostly carbapenemase-producing cefepime-nonsusceptible strains of the family
Enterobacteriaceae
, we evaluated the MICs of cefepime in the presence of various fixed AAI101 concentrations (1, 2, 4, 8, and 16 mg/liter) and the
in vivo
efficacy of simulated human doses of cefepime and cefepime-AAI101 in a neutropenic murine thigh infection model. At 2 h after inoculation, mice were dosed with regimens that provided a profile mimicking the free drug concentration-time profile observed in humans given cefepime at 2 g every 8 h (q8h; as a 30-min infusion) or cefepime-AAI101 at 2 g/0.5 g q8h (as a 30-min infusion). Efficacy was determined by calculation of the change in thigh bacterial density (log
10
number of CFU) after 24 h relative to the starting inoculum (0 h). After 24 h, bacterial growth of 2.7 ± 0.1 log
10
CFU (mean ± standard error) was observed in control animals. Efficacy for cefepime monotherapy was observed against only 3 isolates, whereas increases in bacterial density similar to that in the control animals were noted for the remaining 17 strains (all with cefepime MICs of ≥64 mg/liter). The humanized cefepime-AAI101 dosing regimen resulted in bacterial reductions of ≥0.5 log
10
CFU for 12 of the 20 strains. Evaluation of efficacy as a function of the fraction of the dosing interval during which free drug concentrations were above the MIC determined with different fixed concentrations of AAI101 suggested that a fixed concentration of 8 mg/liter AAI101 is most predictive of
in vivo
activity for the studied regimen.
Persistence and Epidemic Propagation of a Pseudomonas aeruginosa Sequence Type 235 Clone Harboring an IS
26
Composite Transposon Carrying the
bla
IMP-1
Integron in Hiroshima, Japan, 2005 to 2012
Authors: Shimizu Wataru , Kayama Shizuo , Kouda Shuntaro , Ogura Yoshitoshi , Kobayashi Kanao , Shigemoto Norifumi , Shimada Norimitsu , Yano Raita , Hisatsune Junzo , Kato Fuminori , Hayashi Tetsuya , Sueda Taijiro , Ohge Hiroki , Sugai Motoyuki
Published: February 2015

A 9-year surveillance for multidrug-resistant (MDR)
Pseudomonas aeruginosa
in the Hiroshima region showed that the number of isolates harboring the metallo-β-lactamase gene
bla
IMP-1
abruptly increased after 2004, recorded the highest peak in 2006, and showed a tendency to decline afterwards, indicating a history of an epidemic. PCR mapping of the variable regions of the integrons showed that this epidemic was caused by the clonal persistence and propagation of an MDR
P. aeruginosa
strain harboring the
bla
IMP-1
gene and an aminoglycoside 6′-
N
-acetyltransferase gene,
aac(6
′
)-Iae
in a class I integron (In113), whose integrase gene
intl1
was disrupted by an IS
26
insertion. Sequence analysis of the representative strain PA058447 resistance element containing the In113-derived gene cassette array showed that the element forms an IS
26
transposon embedded in the chromosome. It has a Tn
21
backbone and is composed of two segments sandwiched by three IS
26
s. In Japan, clonal nationwide expansion of an MDR
P. aeruginosa
NCGM2.S1 harboring chromosomally encoded In113 with intact
intl1
is reported. Multilocus sequence typing and genomic comparison strongly suggest that PA058447 and NCGM2.S1 belong to the same clonal lineage. Moreover, the structures of the resistance element in the two strains are very similar, but the sites of insertion into the chromosome are different. Based on tagging information of the IS
26
present in both resistance elements, we suggest that the MDR
P. aeruginosa
clone causing the epidemic in Hiroshima for the past 9 years originated from a common ancestor genome of PA058447 and NCGM2.S1 through an IS
26
insertion into
intl1
of In113 and through IS
26
-mediated genomic rearrangements.
Relationship between Azithromycin Susceptibility and Administration Efficacy for Nontypeable Haemophilus influenzae Respiratory Infection
Authors: Euba Begoña , Moleres Javier , Viadas Cristina , Barberán Montserrat , Caballero Lucía , Grilló María-Jesús , Bengoechea José Antonio , de-Torres Juan Pablo , Liñares Josefina , Leiva José , Garmendia Junkal
Published: February 2015

NontypeableHaemophilus influenzae(NTHI) is an opportunistic pathogen that is an important cause of acute exacerbations of chronic obstructive pulmonary disease (AECOPD). COPD is an inflammatory disease of the airways, and exacerbations are acute inflammatory events superimposed on this background of chronic inflammation. Azithromycin (AZM) is a macrolide antibiotic with antibacterial and anti-inflammatory properties and a clinically proven potential for AECOPD prevention and management. Relationships between AZM efficacy and resistance by NTHI and between bactericidal and immunomodulatory effects on NTHI respiratory infection have not been addressed. In this study, we employed two pathogenic NTHI strains with different AZM susceptibilities (NTHI 375 [AZM susceptible] and NTHI 353 [AZM resistant]) to evaluate the prophylactic and therapeutic effects of AZM on the NTHI-host interplay. At the cellular level, AZM was bactericidal toward intracellular NTHI inside alveolar and bronchial epithelia and alveolar macrophages, and it enhanced NTHI phagocytosis by the latter cell type. These effects correlated with the strain MIC of AZM and the antibiotic dose. Additionally, the effect of AZM on NTHI infection was assessed in a mouse model of pulmonary infection. AZM showed both preventive and therapeutic efficacies by lowering NTHI 375 bacterial counts in lungs and bronchoalveolar lavage fluid (BALF) and by reducing histopathological inflammatory lesions in the upper and lower airways of mice. Conversely, AZM did not reduce bacterial loads in animals infected with NTHI 353, in which case a milder anti-inflammatory effect was also observed. Together, the results of this work link the bactericidal and anti-inflammatory effects of AZM and frame the efficacy of this antibiotic against NTHI respiratory infection.
Synthesis of a Sugar-Based Thiosemicarbazone Series and Structure-Activity Relationship versus the Parasite Cysteine Proteases Rhodesain, Cruzain, and Schistosoma mansoni Cathepsin B1
Authors: Fonseca Nayara Cristina , da Cruz Luana Faria , da Silva Villela Filipe , do Nascimento Pereira Glaécia Aparecida , de Siqueira-Neto Jair Lage , Kellar Danielle , Suzuki Brian M. , Ray Debalina , de Souza Thiago Belarmino , Alves Ricardo José , Júnior Policarpo Ademar Sales , Romanha Alvaro José , Murta Silvane Maria Fonseca , McKerrow James H. , Caffrey Conor R. , de Oliveira Renata Barbosa , Ferreira Rafaela Salgado
Published: February 2015

The pressing need for better drugs against Chagas disease, African sleeping sickness, and schistosomiasis motivates the search for inhibitors of cruzain, rhodesain, and
Schistosoma mansoni
CB1 (SmCB1), the major cysteine proteases from
Trypanosoma cruzi
,
Trypanosoma brucei
, and
S. mansoni
, respectively. Thiosemicarbazones and heterocyclic analogues have been shown to be both antitrypanocidal and inhibitory against parasite cysteine proteases. A series of compounds was synthesized and evaluated against cruzain, rhodesain, and SmCB1 through biochemical assays to determine their potency and structure-activity relationships (SAR). This approach led to the discovery of 6 rhodesain, 4 cruzain, and 5 SmCB1 inhibitors with 50% inhibitory concentrations (IC
50
s) of ≤10 μM. Among the compounds tested, the thiosemicarbazone derivative of peracetylated galactoside (compound 4i) was discovered to be a potent rhodesain inhibitor (IC
50
= 1.2 ± 1.0 μM). The impact of a range of modifications was determined; removal of thiosemicarbazone or its replacement by semicarbazone resulted in virtually inactive compounds, and modifications in the sugar also diminished potency. Compounds were also evaluated
in vitro
against the parasites
T. cruzi
,
T. brucei
, and
S. mansoni
, revealing active compounds among this series.
Chemical Inhibition of Bacterial Ribosome Biogenesis Shows Efficacy in a Worm Infection Model
Authors: Stokes Jonathan M. , Selin Carrie , Cardona Silvia T. , Brown Eric D.
Published: February 2015

The development of antibacterial compounds that perturb novel processes is an imperative in the challenge presented by widespread antibiotic resistance. While many antibiotics target the ribosome, molecules that inhibit ribosome assembly have yet to be used in this manner. Here we show that a novel inhibitor of ribosome biogenesis, lamotrigine, is capable of rescuing
Caenorhabditis elegans
from an established
Salmonella
infection, revealing that ribosome biogenesis is a promising target for the development of new antibiotics.
Drug Resistance of Clinical Varicella-Zoster Virus Strains Confirmed by Recombinant Thymidine Kinase Expression and by Targeted Resistance Mutagenesis of a Cloned Wild-Type Isolate
Authors: Brunnemann Anne-Kathrin , Bohn-Wippert Kathrin , Zell Roland , Henke Andreas , Walther Martin , Braum Oliver , Maschkowitz Gregor , Fickenscher Helmut , Sauerbrei Andreas , Krumbholz Andi
Published: February 2015

In this study, approaches were developed to examine the phenotypes of nonviable clinical varicella-zoster virus (VZV) strains with amino acid substitutions in the thymidine kinase (TK) (open reading frame 36 [ORF36]) and/or DNA polymerase (Pol) (ORF28) suspected to cause resistance to antivirals. Initially, recombinant TK proteins containing amino acid substitutions described as known or suspected causes of antiviral resistance were analyzed by measuring the TK activity by applying a modified commercial enzyme immunoassay. To examine the effects of these TK and Pol substitutions on the replication of recombinant virus strains, the method of
en passant
mutagenesis was used. Targeted mutations within ORF36 and/or ORF28 and an autonomously expressed gene of the monomeric red fluorescent protein for plaque identification were introduced into the European wild-type VZV strain HJO. Plaque reduction assays revealed that the amino acid substitutions with unknown functions in TK, Q303stop, N334stop, A163stop, and the deletion of amino acids 7 to 74 aa (Δaa 7 to 74), were associated with resistance against acyclovir (ACV), penciclovir, or brivudine, whereas the L73I substitution and the Pol substitutions T237K and A955T revealed sensitive viral phenotypes. The results were confirmed by quantitative PCR by measuring the viral load under increasing ACV concentrations. In conclusion, analyzing the enzymatic activities of recombinant TK proteins represent a useful tool for evaluating the significance of amino acid substitutions in the antiviral resistance of clinical VZV strains. However, direct testing of replication-competent viruses by the introduction of nonsynonymous mutations in a VZV bacterial artificial chromosome using
en passant
mutagenesis led to reliable phenotypic characterization results.
In-Feed Supplementation of
trans
-Cinnamaldehyde Reduces Layer-Chicken Egg-Borne Transmission of Salmonella enterica Serovar Enteritidis
Authors: Upadhyaya Indu , Upadhyay Abhinav , Kollanoor-Johny Anup , Mooyottu Shankumar , Baskaran Sangeetha A. , Yin Hsin-Bai , Schreiber David T. , Khan Mazhar I. , Darre Michael J. , Curtis Patricia A. , Venkitanarayanan Kumar
Published: February 2015

Salmonella enterica
serovar Enteritidis is a major foodborne pathogen in the United States, causing gastroenteritis in humans, primarily through consumption of contaminated eggs. Chickens are the reservoir host of
S
. Enteritidis. In layer hens,
S
. Enteritidis colonizes the intestine and migrates to various organs, including the oviduct, leading to egg contamination. This study investigated the efficacy of in-feed supplementation with
trans
-cinnamaldehyde (TC), a generally recognized as safe (GRAS) plant compound obtained from cinnamon, in reducing
S
. Enteritidis cecal colonization and systemic spread in layers. Additionally, the effect of TC on
S
. Enteritidis virulence factors critical for macrophage survival and oviduct colonization was investigated
in vitro
. The consumer acceptability of eggs was also determined by a triangle test. Supplementation of TC in feed for 66 days at 1 or 1.5% (vol/wt) for 40- or 25-week-old layer chickens decreased the amounts of
S
. Enteritidis on eggshell and in yolk (
P
< 0.001). Additionally,
S
. Enteritidis persistence in the cecum, liver, and oviduct in TC-supplemented birds was decreased compared to that in controls (
P
< 0.001). No significant differences in feed intake, body weight, or egg production in birds or in consumer acceptability of eggs were observed (
P
> 0.05).
In vitro
cell culture assays revealed that TC reduced
S
. Enteritidis adhesion to and invasion of primary chicken oviduct epithelial cells and reduced
S
. Enteritidis survival in chicken macrophages (
P
< 0.001). Follow-up gene expression analysis using real-time quantitative PCR (qPCR) showed that TC downregulated the expression of
S
. Enteritidis virulence genes critical for chicken oviduct colonization (
P
< 0.001). The results suggest that TC may potentially be used as a feed additive to reduce egg-borne transmission of
S
. Enteritidis.
Oxidative Stress Correlates with Wolbachia-Mediated Antiviral Protection in Wolbachia-Drosophila Associations
Authors: Wong Zhee Sheen , Brownlie Jeremy C. , Johnson Karyn N.
Published: February 2015

Wolbachia
mediates antiviral protection in insect hosts and is being developed as a potential biocontrol agent to reduce the spread of insect-vectored viruses. Definition of the molecular mechanism that generates protection is important for understanding the tripartite interaction between host insect,
Wolbachia
, and virus. Elevated oxidative stress was previously reported for a mosquito line experimentally infected with
Wolbachia
, suggesting that oxidative stress is important for
Wolbachia
-mediated antiviral protection. However,
Wolbachia
experimentally introduced into mosquitoes impacts a range of host fitness traits, some of which are unrelated to antiviral protection. To explore whether elevated oxidative stress is associated with antiviral protection in
Wolbachia
-infected insects, we analyzed oxidative stress of five
Wolbachia
-infected
Drosophila
lines. In flies infected with protective
Wolbachia
strains, hydrogen peroxide concentrations were 1.25- to 2-fold higher than those in paired fly lines cured of
Wolbachia
infection. In contrast, there was no difference in the hydrogen peroxide concentrations in flies infected with nonprotective
Wolbachia
strains compared to flies cured of
Wolbachia
infection. Using a
Drosophila
mutant that produces increased levels of hydrogen peroxide, we investigated whether flies with high levels of endogenous reactive oxygen species had altered responses to virus infection and found that flies with high levels of endogenous hydrogen peroxide were less susceptible to virus-induced mortality. Taken together, these results suggest that elevated oxidative stress correlates with
Wolbachia
-mediated antiviral protection in natural
Drosophila
hosts.
Responses of Yeast Biocontrol Agents to Environmental Stress
Authors: Sui Yuan , Wisniewski Michael , Droby Samir , Liu Jia
Published: February 2015

Biological control of postharvest diseases, utilizing wild species and strains of antagonistic yeast species, is a research topic that has received considerable attention in the literature over the past 30 years. In principle, it represents a promising alternative to chemical fungicides for the management of postharvest decay of fruits, vegetables, and grains. A yeast-based biocontrol system is composed of a tritrophic interaction between a host (commodity), a pathogen, and a yeast species, all of which are affected by environmental factors such as temperature, pH, and UV light as well as osmotic and oxidative stresses. Additionally, during the production process, biocontrol agents encounter various severe abiotic stresses that also impact their viability. Therefore, understanding the ecological fitness of the potential yeast biocontrol agents and developing strategies to enhance their stress tolerance are essential to their efficacy and commercial application. The current review provides an overview of the responses of antagonistic yeast species to various environmental stresses, the methods that can be used to improve stress tolerance and efficacy, and the related mechanisms associated with improved stress tolerance.
Yeast β-1,6-Glucan Is a Primary Target for the Saccharomyces cerevisiae K2 Toxin
Authors: Lukša Juliana , Podoliankaitė Monika , Vepštaitė Iglė , Strazdaitė-Žielienė Živilė , Urbonavičius Jaunius , Servienė Elena
Published: February 2015

Certain
Saccharomyces cerevisiae
strains secrete different killer proteins of double-stranded-RNA origin. These proteins confer a growth advantage to their host by increasing its survival. K2 toxin affects the target cell by binding to the cell surface, disrupting the plasma membrane integrity, and inducing ion leakage. In this study, we determined that K2 toxin saturates the yeast cell surface receptors in 10 min. The apparent amount of K2 toxin, bound to a single cell of wild type yeast under saturating conditions, was estimated to be 435 to 460 molecules. It was found that an increased level of β-1,6-glucan directly correlates with the number of toxin molecules bound, thereby impacting the morphology and determining the fate of the yeast cell. We observed that the binding of K2 toxin to the yeast surface receptors proceeds in a similar manner as in case of the related K1 killer protein. It was demonstrated that the externally supplied pustulan, a poly-β-1,6-glucan, but not the glucans bearing other linkage types (such as laminarin, chitin, and pullulan) efficiently inhibits the K2 toxin killing activity. In addition, the analysis of toxin binding to the intact cells and spheroplasts confirmed that majority of K2 protein molecules attach to the β-1,6-glucan, rather than the plasma membrane-localized receptors. Taken together, our results reveal that β-1,6-glucan is a primary target of K2 toxin and is important for the execution of its killing property.
Crucial and Diverse Role of the Interleukin-33/ST2 Axis in Infectious Diseases
Authors: Rostan Octavie , Arshad Muhammad Imran , Piquet-Pellorce Claire , Robert-Gangneux Florence , Gangneux Jean-Pierre , Samson Michel
Published: February 2015

Interleukin-33 (IL-33) has now emerged as a cytokine with diverse and pleiotropic functions in various infectious and inflammatory diseases. IL-33 is expressed by epithelial cells, endothelial cells, fibroblasts, and hepatocytes. The target cells of IL-33 are Th2 cells, basophils, dendritic cells, mast cells, macrophages, NKT cells, and nuocytes, newly discovered natural helper cells/innate lymphoid cells bearing the ST2 receptor. IL-33 has dual functions, both as a traditional cytokine and as a nuclear factor that regulates gene transcription. IL-33 functions as an “alarmin” released following cell death, as a biomarker, and as a vaccine adjuvant, with proinflammatory and protective effects during various infections. The exacerbated or protective role of the IL-33/ST2 axis during different infections is dependent upon the organ involved, type of infectious agent, whether the infection is acute or chronic, the invasiveness of the infectious agent, the host immune compartment, and cellular and cytokine microenvironments. In this review, we focus on recent advances in the understanding of the role of the IL-33/ST2 axis in various viral, bacterial, fungal, helminth, and protozoal infectious diseases gained from animal models and studies in human patients. The functional role of IL-33 and ST2 during experimentally induced infections has been summarized by accumulating the data for IL-33- and ST2-deficient mice or for mice exogenously administered IL-33. In summary, exploring the crucial and diverse roles of the IL-33/ST2 axis during infections may help in the development of therapeutic interventions for a wide range of infectious diseases.
Ixodes ricinus Salivary Serpin IRS-2 Affects Th17 Differentiation via Inhibition of the Interleukin-6/STAT-3 Signaling Pathway
Authors: Páleníková Jana , Lieskovská Jaroslava , Langhansová Helena , Kotsyfakis Michalis , Chmelař Jindřich , Kopecký Jan
Published: February 2015

Th17 cells constitute a subset of CD4+T lymphocytes that play a crucial role in protection against extracellular bacteria and fungi. They are also associated with tissue injury in autoimmune and inflammatory diseases. Here, we report that serpin from the tickIxodes ricinus, IRS-2, inhibits Th17 differentiation by impairment of the interleukin-6 (IL-6)/STAT-3 signaling pathway. Following activation, mature dendritic cells produce an array of cytokines, including the pleiotropic cytokine IL-6, which triggers the IL-6 signaling pathway. The major transcription factor activated by IL-6 is STAT-3. We show that IRS-2 selectively inhibits production of IL-6 in dendritic cells stimulated withBorreliaspirochetes, which leads to attenuated STAT-3 phosphorylation and finally to impaired Th17 differentiation. The results presented extend the knowledge about the effect of tick salivary serpins on innate immunity cells and their function in driving adaptive immune responses.
Differential Immunodetection of Toxin B from Highly Virulent Clostridium difficile BI/NAP-1/027
Authors: Pollock Nira R. , Song Linan , Zhao Mingwei , Duffy David C. , Chen Xinhua , Sambol Susan P. , Gerding Dale N. , Kelly Ciarán P.
Published: February 2015

We developed a simple immunoassay capable of differentially detecting toxin B from highly virulent strains of
Clostridium difficile
(BI/NAP-1/027) in stool. This assay can simultaneously confirm the presence of
in vivo
toxin production and provide strain-related information relevant to infection control epidemiology and disease prognosis.
Gammaherpesvirus Tegument Protein ORF33 Is Associated with Intranuclear Capsids at an Early Stage of the Tegumentation Process
Authors: Shen Sheng , Jia Xing , Guo Haitao , Deng Hongyu
Published: February 2015

Herpesvirus nascent capsids, after assembly in the nucleus, must acquire a variety of tegument proteins during maturation. However, little is known about the identity of the tegument proteins that are associated with capsids in the nucleus or the molecular mechanisms involved in the nuclear egress of capsids into the cytoplasm, especially for the two human gammaherpesviruses Epstein-Barr virus (EBV) and Kaposi's sarcoma-associated herpesvirus (KSHV), due to a lack of efficient lytic replication systems. Murine gammaherpesvirus 68 (MHV-68) is genetically related to human gammaherpesviruses and serves as an excellent model to study the
de novo
lytic replication of gammaherpesviruses. We have previously shown that open reading frame 33 (ORF33) of MHV-68 is a tegument protein of mature virions and is essential for virion assembly and egress. However, it remains unclear how ORF33 is incorporated into virions. In this study, we first show that the endogenous ORF33 protein colocalizes with capsid proteins at discrete areas in the nucleus during viral infection. Cosedimentation analysis as well as an immunoprecipitation assay demonstrated that ORF33 is associated with both nuclear and cytoplasmic capsids. An immunogold labeling experiment using an anti-ORF33 monoclonal antibody revealed that ORF33-rich areas in the nucleus are surrounded by immature capsids. Moreover, ORF33 is associated with nucleocapsids prior to primary envelopment as well as with mature virions in the cytoplasm. Finally, we show that ORF33 interacts with two capsid proteins, suggesting that nucleocapsids may interact with ORF33 in a direct manner. In summary, we identified ORF33 to be a tegument protein that is associated with intranuclear capsids prior to primary envelopment, likely through interacting with capsid proteins in a direct manner.

IMPORTANCE
Morphogenesis is an essential step in virus propagation that leads to the generation of progeny virions. For herpesviruses, this is a complicated process that starts in the nucleus. Although the process of capsid assembly and genome packaging is relatively well understood, how capsids acquire tegument (the layer between the capsid and the envelope in a herpesvirus virion) and whether the initial tegumentation process takes place in the nucleus remain unclear. We previously showed that ORF33 of MHV-68 is a tegument protein and functions in both the nuclear egress of capsids and final virion maturation in the cytoplasm. In the present study, we show that ORF33 is associated with intranuclear capsids prior to primary envelopment and identify novel interactions between ORF33 and two capsid proteins. Our work provides new insights into the association between tegument proteins and nucleocapsids at an early stage of the virion maturation process for herpesviruses.
A Novel Endogenous Betaretrovirus in the Common Vampire Bat (Desmodus rotundus) Suggests Multiple Independent Infection and Cross-Species Transmission Events
Authors: Escalera-Zamudio Marina , Mendoza M. Lisandra Zepeda , Heeger Felix , Loza-Rubio Elizabeth , Rojas-Anaya Edith , Méndez-Ojeda Maria L. , Taboada Blanca , Mazzoni Camila J. , Arias Carlos F. , Greenwood Alex D.
Published: February 2015

The
Desmodus rotundus
endogenous betaretrovirus (DrERV) is fixed in the vampire bat
D. rotundus
population and in other phyllostomid bats but is not present in all species from this family. DrERV is not phylogenetically related to Old World bat betaretroviruses but to betaretroviruses from rodents and New World primates, suggesting recent cross-species transmission. A recent integration age estimation of the provirus in some taxa indicates that an exogenous counterpart might have been in recent circulation.
Infection History Determines the Differentiation State of Human CD8
+
T Cells
Authors: van Aalderen Michiel C. , Remmerswaal Ester B. M. , Verstegen Niels J. M. , Hombrink Pleun , ten Brinke Anja , Pircher Hanspeter , Kootstra Neeltje A. , ten Berge Ineke J. M. , van Lier René A. W.
Published: February 2015

After the resolution of the acute phase of infection, otherwise quiescent antigen-experienced CD8
+
T cells confer rapid protection upon reinfection with viral pathogens or, in the case of persistent viruses, help to maintain control of the infection. Depending on the type of virus, antigen-specific CD8
+
T cells have distinct traits, ranging from typical memory cell properties in the case of rapidly cleared viruses to immediate effector functions for persistent viruses. We here show that both the differentiation stage, defined by the expression of cell surface markers, such as CD45RA, CCR7, CD28, and CD27, and distinct expression levels of T-bet and eomesodermin (Eomes) predict the functional profile of antigen-experienced CD8
+
T cells. Furthermore, virus-specific CD8
+
T cells targeting different respiratory syncytial virus-, influenza A virus-, Epstein-Barr virus (EBV)-, human cytomegalovirus (hCMV)-, and HIV-1-specific epitopes adopt distinct T-bet and Eomes expression patterns that appear to be installed early during the primary response. Importantly, the associations between surface phenotype, T-bet/Eomes expression levels, and the expression of markers that predict CD8
+
T-cell function change according to viral infection history, particularly against the background of HIV-1 and, to lesser extent, of human cytomegalovirus and/or Epstein-Barr virus infection. Thus, the functionality of human antigen-experienced CD8
+
T cells follows at least two dimensions, one outlined by the surface phenotype and another by the T-bet/Eomes expression levels, which are determined by previous or persistent viral challenges.

IMPORTANCE
Functional human CD8
+
T-cell subsets have been defined using surface markers like CD45RA, CCR7, CD28, and CD27. However, the induction of function-defining traits, like granzyme B expression, is controlled by transcription factors like T-bet and Eomes. Here, we describe how T-bet and Eomes levels distinctly relate to the expression of molecules predictive for CD8
+
T-cell function in a surface phenotype-independent manner. Importantly, we found that central memory and effector memory CD8
+
T-cell subsets differentially express T-bet, Eomes, and molecules predictive for function according to viral infection history, particularly so in the context of HIV-1 infection and, to lesser extent, of latent EBV- and/or hCMV-infected, otherwise healthy adults. Finally, we show that the distinct phenotypes and T-bet/Eomes levels of different virus-specific CD8
+
T-cell populations are imprinted early during the acute phase of primary infection
in vivo
. These findings broaden our understanding of CD8
+
T-cell differentiation.
Cellular Transformation of Mouse Embryo Fibroblasts in the Absence of Activator E2Fs
Authors: Gupta Tushar , Sáenz Robles Maria Teresa , Pipas James M.
Published: February 2015

The E2F family of transcription factors, broadly divided into activator and repressor E2Fs, regulates cell cycle genes. Current models indicate that activator E2Fs are necessary for cell cycle progression and tumorigenesis and are also required to mediate transformation induced by DNA tumor viruses. E2Fs are negatively regulated by the retinoblastoma (RB) family of tumor suppressor proteins, and virus-encoded oncogenes disrupt the RB-E2F repressor complexes. This results in the release of activator E2Fs and induction of E2F-dependent genes. In agreement, expression of large tumor T antigens (TAg) encoded by polyomaviruses in mammalian cells results in increased transcriptional levels of E2F target genes. In addition, tumorigenesis induced by transgenic expression of simian virus 40 (SV40) TAg in choroid plexus or intestinal villi requires at least one activator E2F. In contrast, we show that SV40 TAg-induced transformation in mouse embryonic fibroblasts is independent of activator E2Fs. This work, coupled with recent studies showing that proliferation in stem and progenitor cells is independent of activator E2Fs, suggests the presence of parallel pathways governing cell proliferation and tumorigenesis.

IMPORTANCE
The RB-E2F pathway is altered in many cancers and is also targeted by DNA tumor viruses. Viral oncoprotein action on RBs results in the release of activator E2Fs and upregulation of E2F target genes; thus, activator E2Fs are considered essential for normal and tumorigenic cell proliferation. However, we have observed that SV40 large T antigen can induce cell proliferation and transformation in the absence of activator E2Fs. Our results also suggest that TAg action on pRBs regulates both E2F-dependent and -independent pathways that govern proliferation. Thus, specific cell proliferation pathways affected by RB alterations in cancer may be a factor in tumor behavior and response to therapy.
Novel Pseudotaxis Mechanisms Improve Migration of Straight-Swimming Bacterial Mutants Through a Porous Environment
Authors: Mohari Bitan , Licata Nicholas A. , Kysela David T. , Merritt Peter M. , Mukhopadhay Suchetana , Brun Yves V. , Setayeshgar Sima , Fuqua Clay
Published: February 2015

Bacterial locomotion driven by flagella is given directionality by the chemotaxis signal transduction network. In the classic plate assays of migration in porous motility agar, efficient motility is compromised in chemotaxis mutants of diverse bacteria. Nonchemotactic mutants become trapped within the agar matrix. Suppressor mutations that prevent this entanglement but do not restore chemotaxis, a phenomenon designated pseudotaxis, were first reported to arise for
Escherichia coli
. In this study, novel mechanisms of pseudotaxis have been identified for the plant-pathogenic alphaproteobacterium
Agrobacterium tumefaciens
. Mutants with chemotaxis mutation suppressor (cms) mutations that impart enhanced migration in motility agar compared to that of their straight-swimming, nonchemotactic parent were isolated. We find that pseudotaxis in A. tumefaciens occurs most commonly via mutations in the D1 domain of the flagellar hook protein, FlgE, but it can also be found less frequently to be due to mutations in the hook length regulator, FliK, or in the motor protein, MotA. Single-cell-tracking studies of cms mutants in bulk medium clearly reveal frequent changes in the direction of swimming, similar to the swimming of strains that are proficient for chemotaxis, but independent of a sensory mechanism. Our results suggest that the tumbling process can be tuned through mutation and evolution to optimize migration through complex, porous environments.

IMPORTANCE
Chemotaxis sensory networks control direct bacterial motility by modulating flagellar rotary motion, alternating cellular movement between runs and tumbles. The straight-swimming phenotype of chemotaxis-deficient cells yields nonexpanding colonies in motility agar. Enhanced, chemotaxis-independent spreading, dubbed pseudotaxis, has been observed in
Escherichia coli
mutants. We have identified novel pseudotaxis mutations in
Agrobacterium tumefaciens
that alter the flagellar hook structure or motor, leading to randomly occurring reorientations observed in single-cell tracking studies in bulk medium. These directional changes allow the cells to migrate more efficiently than the parent strain through the agar matrix, independently of the chemotaxis process. These findings reveal that tumbling can be tuned for effective navigation in complex porous environments, analogous to the natural habitats for many bacteria, and provide evidence for the strong selective pressure exerted by the external environment on the basal pattern of motility, even in the absence of chemotaxis.