bluuebunny/crossref_metadata_2025 huggingface dataset:
In Vitro
and
In Vivo
Activities of E-101 Solution against Acinetobacter baumannii Isolates from U.S. Military Personnel
Authors: Denys G. A. , Davis J. C. , O'Hanley P. D. , Stephens J. T.
Published: April 2011

We evaluated the
in vitro
and
in vivo
activity of a novel topical myeloperoxidase-mediated antimicrobial, E-101 solution, against 5 multidrug-resistant
Acinetobacter baumannii
isolates recovered from wounded American soldiers. Time-kill studies demonstrated rapid bactericidal activity against all
A. baumannii
strains tested in the presence of 3% blood. The
in vitro
bactericidal activity of E-101 solution against
A. baumannii
strains was confirmed in a full-thickness excision rat model. Additional
in vivo
studies appear warranted.
Disulfide-Mediated Oligomer Formation in Borrelia burgdorferi Outer Surface Protein C, a Critical Virulence Factor and Potential Lyme Disease Vaccine Candidate
Authors: Earnhart Christopher G. , Rhodes DeLacy V. L. , Marconi Richard T.
Published: April 2011

Borrelia burgdorferiOspC is an outer membrane lipoprotein required for the establishment of infection in mammals. Due to its universal distribution amongB. burgdorferisensu lato strains and high antigenicity, it is being explored for the development of a next-generation Lyme disease vaccine. An understanding of the surface presentation of OspC will facilitate efforts to maximize its potential as a vaccine candidate. OspC forms homodimers at the cell surface, and it has been hypothesized that it may also form oligomeric arrays. Here, we employ site-directed mutagenesis to test the hypothesis that interdimeric disulfide bonds at cysteine 130 (C130) mediate oligomerization.B. burgdorferiB31ospCwas replaced with a C130A substitution mutant to yield strain B31::ospC(C130A). Recombinant protein was also generated. Disulfide-bond-dependent oligomer formation was demonstrated and determined to be dependent on C130. Oligomerization was not required forin vivofunction, as B31::ospC(C130A) retained infectivity and disseminated normally. The total IgG response and the induced isotype pattern were similar between mice infected with untransformed B31 and those infected with the B31::ospC(C130A) strain. These data indicate that the immune response to OspC is not significantly altered by formation of OspC oligomers, a finding that has significant implications in Lyme disease vaccine design.
Virulence Gene Pool Detected in Bovine Group C Streptococcus dysgalactiae subsp. dysgalactiae Isolates by Use of a Group A S. pyogenes Virulence Microarray
Authors: Rato Márcia G. , Nerlich Andreas , Bergmann René , Bexiga Ricardo , Nunes Sandro F. , Vilela Cristina L. , Santos-Sanches Ilda , Chhatwal Gursharan S.
Published: April 2011

A custom-designed microarray containing 220 virulence genes of
Streptococcus pyogenes
(group A
Streptococcus
[GAS]) was used to test group C
Streptococcus dysgalactiae
subsp.
dysgalactiae
(GCS) field strains causing bovine mastitis and group C or group G
Streptococcus dysgalactiae
subsp.
equisimilis
(GCS/GGS) isolates from human infections, with the latter being used for comparative purposes, for the presence of virulence genes. All bovine and all human isolates carried a fraction of the 220 genes (23% and 39%, respectively). The virulence genes encoding streptolysin S, glyceraldehyde-3-phosphate dehydrogenase, the plasminogen-binding M-like protein PAM, and the collagen-like protein SclB were detected in the majority of both bovine and human isolates (94 to 100%). Virulence factors, usually carried by human beta-hemolytic streptococcal pathogens, such as streptokinase, laminin-binding protein, and the C5a peptidase precursor, were detected in all human isolates but not in bovine isolates. Additionally, GAS bacteriophage-associated virulence genes encoding superantigens, DNase, and/or streptodornase were detected in bovine isolates (72%) but not in the human isolates. Determinants located in non-bacteriophage-related mobile elements, such as the gene encoding R28, were detected in all bovine and human isolates. Several virulence genes, including genes of bacteriophage origin, were shown to be expressed by reverse transcriptase PCR (RT-PCR). Phylogenetic analysis of superantigen gene sequences revealed a high level (>98%) of identity among genes of bovine GCS, of the horse pathogen
Streptococcus equi
subsp.
equi
, and of the human pathogen GAS. Our findings indicate that alpha-hemolytic bovine GCS, an important mastitis pathogen and considered to be a nonhuman pathogen, carries important virulence factors responsible for virulence and pathogenesis in humans.
Persistent Carriage and Infection by Multidrug-Resistant Escherichia coli ST405 Producing NDM-1 Carbapenemase: Report on the First Italian Cases
Authors: D'Andrea Marco Maria , Venturelli Claudia , Giani Tommaso , Arena Fabio , Conte Viola , Bresciani Paola , Rumpianesi Fabio , Pantosti Annalisa , Narni Franco , Rossolini Gian Maria
Published: April 2011

We report on the first detection of the NDM-1 carbapenemase in Italy, in
Escherichia coli
isolated in October 2009. Prolonged colonization and relapsing infection by NDM-1-positive
E. coli
were observed in a patient (index case) with an indirect epidemiological link with areas of endemicity. Transient colonization was apparently observed in another patient linked with the index case.
Molecular Characterization of Drug-Resistant
Mycobacterium tuberculosis
Isolates Circulating in China by Multilocus PCR and Electrospray Ionization Mass Spectrometry
Authors: Wang Feifei , Massire Christian , Li Haijing , Cummins Lendell L. , Li Feng , Jin Jialin , Fan Xiaoping , Wang Sen , Shao Lingyun , Zhang Shu , Meng Shufang , Wu Jing , Lu Chanyi , Blyn Lawrence B. , Sampath Rangarajan , Ecker David J. , Zhang Wenhong , Tang Yi-Wei
Published: April 2011

We used multilocus PCR and electrospray ionization mass spectrometry (PCR/ESI-MS) to determine the genotype and drug resistance profiles for 96
Mycobacterium tuberculosis
isolates circulating in regions of high and low tuberculosis (TB) endemicity in China. The dominant principal genetic group (PGG) circulating in China was PGG1, and drug-resistant gene mutations were more diversified in the region of low rather than high TB endemicity.
Evaluation of a Loop-Mediated Isothermal Amplification Assay for Diagnosis of
Clostridium difficile
Infections
Authors: Lalande Valérie , Barrault Laurence , Wadel Sophie , Eckert Catherine , Petit Jean-Claude , Barbut Frédéric
Published: April 2011

A new assay (
illumi
gene
C. difficile
; Meridian Bioscience), based on the original loop-mediated isothermal amplification (LAMP) assay, was evaluated with 472 unformed stools from patients suspected of
Clostridium difficile
infection. Compared to the toxigenic culture, the sensitivity, specificity, and positive and negative predictive values were 91.8, 99.1, 91.8, and 99.1% for the
illumi
gene
C. difficile
assay and 69.4, 100, 100, and 96.6% for the cytotoxicity assay, respectively.
Impact of rpoB Mutations on Reduced Vancomycin Susceptibility in Staphylococcus aureus
Authors: Watanabe Yukiko , Cui Longzhu , Katayama Yuki , Kozue Kishii , Hiramatsu Keiichi
Published: April 2011

Of 38 vancomycin-intermediate
Staphylococcus aureus
(VISA) clinical strains, 27 (71%) possessed a mutation(s) in
rpoB
encoding the β-subunit of RNA polymerase. Furthermore, 95.6% of the rifampin-resistant mutants obtained from 9 methicillin-resistant
S. aureus
(MRSA) clinical isolates showed decreased vancomycin susceptibilities. These data indicate the involvement of an
rpoB
mutation in VISA phenotype expression.
Molecular Characterization and Antimicrobial Susceptibility Testing of Escherichia coli Isolates from Patients with Urinary Tract Infections in 20 Chinese Hospitals
Authors: Cao Xiaoli , Cavaco Lina M. , Lv Yuan , Li Yun , Zheng Bo , Wang Pengyuan , Hasman Henrik , Liu Yucun , Aarestrup Frank M.
Published: April 2011

A total of 222 urinary
Escherichia coli
isolates from 20 tertiary hospitals in 15 different provinces and 4 municipalities in mainland China were characterized by antimicrobial susceptibility, phylogrouping, and the presence of plasmid-mediated quinolone resistance genes. A subset of 138 suspected extended-spectrum cephalosporinase (ESC) producers were examined for genes encoding cephalosporin resistance. Forty-three isolates harboring
bla
CTX-M-14
or
bla
CTX-M-15
were analyzed by pulsed-field gel electrophoresis (PFGE), and plasmids containing these genes were typed using PCR-based replicon typing (PBRT). Thirteen phylogroup B2
bla
CTX-M-14
- and
bla
CTX-M-15
-positive isolates were analyzed by multilocus sequence typing (MLST). A frequent occurrence of resistance (>46%) was observed toward cephalosporins, gentamicin, and fluoroquinolones. Among the 222 isolates, 4
qnrS1
, 4
qepA
, and 16
aac
(
6
′)
-Ib-cr
genes were confirmed. Four major phylogroups (A, B1, B2, and D) and nontypeable isolates (NTs) were found among the isolates, with phylogroup D (54%) being the most common phylogroup. A total of 110 (80%) of the 138 screened isolates harbored
bla
CTX-M
genes, with
bla
CTX-M-14
(71%) and
bla
CTX-M-15
(24%) being the most prevalent of these genes. Nine of the 13 CTX-M-15- or CTX-M-14-containing B2 isolates belonged to ST131. PFGE typing showed a high level of diversity, and plasmid analysis indicated a very large pool of different resistance plasmids mediating the spread of
bla
CTX-M
genes in mainland China. An equally very high frequency of resistance and equally high levels of diversity in phylogroups, PFGE types, and plasmids were observed among community- and hospital-acquired
E. coli
isolates, indicating the presence of a large reservoir in the community and a long-term spread of cephalosporin resistance in China.
Use of bexB To Detect the Capsule Locus in Haemophilus influenzae
Authors: Davis Gregg S. , Sandstedt Sara A. , Patel Mayuri , Marrs Carl F. , Gilsdorf Janet R.
Published: April 2011

Haemophilus influenzae
strains are classified as typeable or nontypeable
H. influenzae
(NTHI) based upon the presence or absence of capsule. In addition to serotyping, which is subject to false-positive results, typeable strains can be identified through the detection of the capsular export gene
bexA
and one of six capsule-specific genes, but this method is resource intensive, especially in characterizing large numbers of strains. To address these challenges, we developed a
bexB
-based method to differentiate true NTHI strains from typeable strains. We validated a PCR-based method to detect
bexB
in 10 strains whose capsule status was well defined. Among 40 strains that were previously serotype positive in clinical microbiology laboratories, 5 lacked
bexA
,
bexB
, and capsule type-specific genes by PCR analysis and thus likely represent false-positive serotyping results. Among 94 additional otitis media, commensal, and serotype b-negative invasive strains, 85 were
bexA
and
bexB
negative and 9 contained either a complete or partial capsule locus, i.e., 8 were
bexA
and
bexB
positive and 1 was
bexA
negative but
bexB
positive. Finally, we adapted the method for use in a high-throughput DNA hybridization-based microarray method, which showed 98.75 and 97.5% concordance to the PCR methods for
bexA
and
bexB
, respectively. In addition,
bexB
showed 84% or greater nucleotide identity among strains containing the capsule locus. In this study, we demonstrate that
bexB
is a reliable proxy for the capsule locus and that its detection provides a simple and reliable method for differentiating strains that lack the entire capsule locus from those containing a partial or complete capsule locus.
Blood Cultures at Central Line Insertion in the Intensive Care Unit: Comparison with Peripheral Venipuncture
Authors: Stohl Sheldon , Benenson Shmuel , Sviri Sigal , Avidan Alexander , Block Colin , Sprung Charles L. , Levin Phillip D.
Published: April 2011

Blood cultures are a key diagnostic test for intensive care unit (ICU) patients; however, contaminants complicate interpretations and lead to unnecessary antibiotic administration and costs. Indications for blood cultures and central venous catheter (CVC) insertions often overlap for ICU patients. Obtaining blood cultures under the strict sterile precautions utilized for CVC insertion might be expected to decrease culture contamination. This retrospective study compared the results of blood cultures taken at CVC insertion, at arterial line insertion, and from peripheral venipuncture in order to validate the advantage of CVC insertion cultures. Cultures from indwelling lines were excluded. Results of 14,589 blood cultures, including 2,736 (19%) CVC, 1,513 (10%) arterial line, and 10,340 (71%) peripheral cultures taken over 5.5 years in two ICUs (general and medical) were analyzed. CVC cultures were contaminated more frequently than arterial line or peripheral cultures (225/2,736 [8%] CVC, 48/1,513 [3%] arterial line, and 378/10,340 (4%) peripheral cultures [
P
< 0.001 for CVC versus peripheral and CVC versus arterial line cultures]). True pathogens were found more frequently in CVC insertion cultures (334/2,736 [12%] CVC, 155/1,513 [10%] arterial line, and 795/10,340 [8%] peripheral cultures [
P
< 0.001 for CVC versus peripheral cultures;
P
= 0.055 for CVC versus arterial line cultures;
P
< 0.001 for peripheral versus arterial line cultures]). Contamination and true-positive rates were similar for culture sets from the two ICUs for each given culture source. Despite superior sterile precautions, cultures taken at the time of central line insertion had a higher contamination rate than did either peripheral or arterial line blood cultures. This may be related to the increased manipulations required for CVC insertion.
Ubiquitin-Specific Peptidase 20 Targets TRAF6 and Human T Cell Leukemia Virus Type 1 Tax To Negatively Regulate NF-κB Signaling
Authors: Yasunaga Junichiro , Lin Frank C. , Lu Xiongbin , Jeang Kuan-Teh
Published: April 2011

NF-κB plays a key role in innate and acquired immunity. Its activity is regulated through intricate signaling networks. Persistent or excessive activation of NF-κB induces diseases, such as autoimmune disorders and malignant neoplasms. Infection by human T cell leukemia virus type 1 (HTLV-1) causes a fatal hematopoietic malignancy termed adult T cell leukemia (ATL). The HTLV-1 viral oncoprotein Tax functions pivotally in leukemogenesis through its potent activation of NF-κB. Recent findings suggest that protein ubiquitination is crucial for proper regulation of NF-κB signaling and for Tax activity. Here, we report that ubiquitin-specific peptidase USP20 deubiquitinates TRAF6 and Tax and suppresses interleukin 1β (IL-1β)- and Tax-induced NF-κB activation. Our results point to USP20 as a key negative regulator of Tax-induced NF-κB signaling.
Strong Human Endogenous Retrovirus-Specific T Cell Responses Are Associated with Control of HIV-1 in Chronic Infection
Authors: SenGupta Devi , Tandon Ravi , Vieira Raphaella G. S. , Ndhlovu Lishomwa C. , Lown-Hecht Rachel , Ormsby Christopher E. , Loh Liyen , Jones R. Brad , Garrison Keith E. , Martin Jeffrey N. , York Vanessa A. , Spotts Gerald , Reyes-Terán Gustavo , Ostrowski Mario A. , Hecht Frederick M. , Deeks Steven G. , Nixon Douglas F.
Published: April 2011

Eight percent of the human genome is composed of human endogenous retroviruses (HERVs), which are thought to be inactive remnants of ancient infections. Previously, we showed that individuals with early HIV-1 infection have stronger anti-HERV T cell responses than uninfected controls. In this study, we investigated whether these responses persist in chronic HIV-1 infection and whether they have a role in the control of HIV-1. Peripheral blood mononuclear cells (PBMCs) from 88 subjects diagnosed with HIV-1 infection for at least 1 year (median duration of diagnosis, 13 years) were tested for responses against HERV peptides in gamma interferon (IFN-γ) enzyme immunospot (ELISPOT) assays. Individuals who control HIV-1 viremia without highly active antiretroviral therapy (HAART) had stronger and broader HERV-specific T cell responses than HAART-suppressed patients, virologic noncontrollers, immunologic progressors, and uninfected controls (
P
< 0.05 for each pairwise comparison). In addition, the magnitude of the anti-HERV T cell response was inversely correlated with HIV-1 viral load (
r
2
= 0.197,
P
= 0.0002) and associated with higher CD4
+
T cell counts (
r
2
= 0.072,
P
= 0.027) in untreated patients. Flow cytometric analyses of an HLA-B51-restricted CD8
+
HERV response in one HIV-1-infected individual revealed a less activated and more differentiated phenotype than that stimulated by a homologous HIV-1 peptide. HLA-B51 tetramer dual staining within this individual confirmed two different T cell populations corresponding to these HERV and HIV-1 epitopes, ruling out cross-reactivity. These findings suggest a possible role for anti-HERV immunity in the control of chronic HIV-1 infection and provide support for a larger effort to design an HIV-1 vaccine that targets conserved antigens such as HERV.
Shifting Hierarchies of Interleukin-10-Producing T Cell Populations in the Central Nervous System during Acute and Persistent Viral Encephalomyelitis
Authors: Puntambekar Shweta S. , Bergmann Cornelia C. , Savarin Carine , Karp Christopher L. , Phares Timothy W. , Parra Gabriel I. , Hinton David R. , Stohlman Stephen A.
Published: April 2011

Interleukin-10 (IL-10) mRNA is rapidly upregulated in the central nervous system (CNS) following infection with neurotropic coronavirus and remains elevated during persistent infection. Infection of transgenic IL-10/green fluorescent protein (GFP) reporter mice revealed that CNS-infiltrating T cells were the major source of IL-10, with minimal IL-10 production by macrophages and resident microglia. The proportions of IL-10-producing cells were initially similar in CD8+and CD4+T cells but diminished rapidly in CD8+T cells as the virus was controlled. Overall, the majority of IL-10-producing CD8+T cells were specific for the immunodominant major histocompatibility complex (MHC) class I epitope. Unlike CD8+T cells, a large proportion of CD4+T cells within the CNS retained IL-10 production throughout persistence. Furthermore, elevated frequencies of IL-10-producing CD4+T cells in the spinal cord supported preferential maintenance of IL-10 production at the site of viral persistence and tissue damage. IL-10 was produced primarily by the CD25+CD4+T cell subset during acute infection but prevailed in CD25−CD4+T cells during the transition to persistent infection and thereafter. Overall, these data demonstrate significant fluidity in the T-cell-mediated IL-10 response during viral encephalitis and persistence. While IL-10 production by CD8+T cells was limited primarily to the time of acute effector function, CD4+T cells continued to produce IL-10 throughout infection. Moreover, a shift from predominant IL-10 production by CD25+CD4+T cells to CD25−CD4+T cells suggests that a transition to nonclassical regulatory T cells precedes and is retained during CNS viral persistence.
Evaluation of the Newcastle Disease Virus F and HN Proteins in Protective Immunity by Using a Recombinant Avian Paramyxovirus Type 3 Vector in Chickens
Authors: Kumar Sachin , Nayak Baibaswata , Collins Peter L. , Samal Siba K.
Published: April 2011

Newcastle disease virus (NDV) belongs to serotype 1 of the avian paramyxoviruses (APMV-1) and causes severe disease in chickens. Current live attenuated NDV vaccines are not fully satisfactory. An alternative is to use a viral vector vaccine that infects chickens but does not cause disease. APMV serotype 3 infects a wide variety of avian species but does not cause any apparent disease in chickens. In this study, we constructed a reverse-genetics system for recovery of infectious APMV-3 strain Netherlands from cloned cDNAs. Two recombinant viruses, rAPMV3-F and rAPMV3-HN, were generated expressing the NDV fusion (F) and hemagglutinin-neuraminidase (HN) proteins, respectively, from added genes. These viruses were used to immunize 2-week-old chickens by the oculonasal route in order to evaluate the contribution of each protein to the induction of NDV-specific neutralizing antibodies and protective immunity. Each virus induced high titers of NDV-specific hemagglutination inhibition and serum neutralizing antibodies, but the response to F protein was greater. Protective immunity was evaluated by challenging the immunized birds 21 days later with virulent NDV via the oculonasal, intramuscular, or intravenous route. With oculonasal or intramuscular challenge, all three recombinant viruses (rAPMV3, rAPMV3-F, and rAPMV3-HN) were protective, while all unvaccinated birds succumbed to death. These results indicated that rAPMV3 alone can provide cross-protection against NDV challenge. However, with intravenous challenge, birds immunized with rAPMV3 were not protected, whereas birds immunized with rAPMV3-F alone or in combination with rAPMV3-HN were completely protected, and birds immunized with rAPMV3-HN alone were partially protected. These results indicate that the NDV F and HN proteins are independent neutralization and protective antigens, but the contribution by F is greater. rAMPV3 represents an avirulent vaccine vector that can be used against NDV and other poultry pathogens.
RAB11A Is Essential for Transport of the Influenza Virus Genome to the Plasma Membrane
Authors: Eisfeld Amie J. , Kawakami Eiryo , Watanabe Tokiko , Neumann Gabriele , Kawaoka Yoshihiro
Published: April 2011

Influenza A virus assembly is a complex process that requires the intersection of pathways involved in transporting viral glycoproteins, the matrix protein, and viral genomes, incorporated in the viral ribonucleoprotein (vRNP) complex, to plasma membrane sites of virion formation. Among these virion components, the mechanism of vRNP delivery is the most incompletely understood. Here, we reveal a functional relationship between the cellular Rab11 GTPase isoform, RAB11A, and vRNPs and show that RAB11A is indispensable for proper vRNP transport to the plasma membrane. Using an immunofluorescence-based assay with a monoclonal antibody that recognizes nucleoprotein in the form of vRNP, we demonstrate association between RAB11A and vRNPs at all stages of vRNP cytoplasmic transport. Abrogation of RAB11A expression through small interfering RNA (siRNA) treatment or disruption of RAB11A function by overexpression of dominant negative or constitutively active proteins caused aberrant vRNP intracellular accumulation, retention in the perinuclear region, and lack of accumulation at the plasma membrane. Complex formation between RAB11A and vRNPs was further established biochemically. Our results uncover a critical host factor with an essential contribution to influenza virus genome delivery and reveal a potential role for RAB11A in the transport of ribonucleoprotein cargo.
Sulfolobus Turreted Icosahedral Virus c92 Protein Responsible for the Formation of Pyramid-Like Cellular Lysis Structures
Authors: Snyder Jamie C. , Brumfield Susan K. , Peng Nan , She Qunxin , Young Mark J.
Published: April 2011

Host cells infected by
Sulfolobus
turreted icosahedral virus (STIV) have been shown to produce unusual pyramid-like structures on the cell surface. These structures represent a virus-induced lysis mechanism that is present in
Archaea
and appears to be distinct from the holin/endolysin system described for DNA bacteriophages. This study investigated the STIV gene products required for pyramid formation in its host
Sulfolobus solfataricus
. Overexpression of STIV open reading frame (ORF) c92 in
S. solfataricus
alone is sufficient to produce the pyramid-like lysis structures in cells. Gene disruption of c92 within STIV demonstrates that c92 is an essential protein for virus replication. Immunolocalization of c92 shows that the protein is localized to the cellular membranes forming the pyramid-like structures.
Helper Component Proteinase of the Genus Potyvirus Is an Interaction Partner of Translation Initiation Factors eIF(iso)4E and eIF4E and Contains a 4E Binding Motif
Authors: Ala-Poikela Marjo , Goytia Elisa , Haikonen Tuuli , Rajamäki Minna-Liisa , Valkonen Jari P. T.
Published: April 2011

The multifunctional helper component proteinase (HCpro) of potyviruses (genus
Potyvirus
;
Potyviridae
) shows self-interaction and interacts with other potyviral and host plant proteins. Host proteins that are pivotal to potyvirus infection include the eukaryotic translation initiation factor eIF4E and the isoform eIF(iso)4E, which interact with viral genome-linked protein (VPg). Here we show that HCpro of
Potato virus A
(PVA) interacts with both eIF4E and eIF(iso)4E, with interactions with eIF(iso)4E being stronger, as judged by the data of a yeast two-hybrid system assay. A bimolecular fluorescence complementation assay on leaves of
Nicotiana benthamiana
showed that HCpro from three potyviruses (PVA,
Potato virus Y
, and
Tobacco etch virus
) interacted with the eIF(iso)4E and eIF4E of tobacco (
Nicotiana tabacum
); interactions with eIF(iso)4E and eIF4E of potato (
Solanum tuberosum
) were weaker. In PVA-infected cells, interactions between HCpro and tobacco eIF(iso)4E were confined to round structures that colocalized with 6K2-induced vesicles. Point mutations introduced to a 4E binding motif identified in the C-terminal region of HCpro debilitated interactions of HCpro with translation initiation factors and were detrimental to the virulence of PVA in plants. The 4E binding motif conserved in HCpro of potyviruses and HCpro-initiation factor interactions suggest new roles for HCpro and/or translation factors in the potyvirus infection cycle.
RNA Structural Domains in Noncoding Regions of the Foot-and-Mouth Disease Virus Genome Trigger Innate Immunity in Porcine Cells and Mice
Authors: Rodríguez-Pulido Miguel , Borrego Belén , Sobrino Francisco , Sáiz Margarita
Published: April 2011

The induction of type I interferons (alpha/beta interferon [IFN-α/β]) in response to viral infection is a crucial step leading to the antiviral state in the host. Viruses produce double-stranded RNA (dsDNA) during their replication cycle that is sensed as nonself by host cells through different receptors. A signaling cascade then is activated to block viral replication and spread. Foot-and-mouth disease virus (FMDV) is a picornavirus that is highly sensitive to IFN, and it causes one of the world's most important animal diseases. In this study, we showed the ability of structural domains predicted to enclose stable dsRNA regions in the 5′- and 3′-noncoding regions (NCRs) of the FMDV genome to trigger an IFN-α/β response in porcine kidney cultured cells and newborn mice. These RNAs, generated by
in vitro
transcription, were able to stimulate IFN-β transcription and induce an antiviral state in SK-6 cells. The induction levels elicited by the different NCR RNAs were compared. Among them, the 3′NCR was identified as a potent IFN activator, and the features in this region involved in signaling have been analyzed. To address whether the FMDV NCR transcripts were able to trigger the innate immune response
in vivo
, Swiss suckling mice were inoculated intraperitoneally with the RNAs. All transcripts induced the innate response in transfected animals, measured as IFN-α/β protein levels, antiviral activity in sera, and reduced susceptibility to FMDV infection. Our work provides new insight into innate responses against FMDV and identifies these small noninfectious RNA molecules as potential adjuvants for vaccine improvement and antiviral strategies against picornaviruses.
Functional Macroautophagy Induction by Influenza A Virus without a Contribution to Major Histocompatibility Complex Class II-Restricted Presentation
Authors: Comber Joseph D. , Robinson Tara M. , Siciliano Nicholas A. , Snook Adam E. , Eisenlohr Laurence C.
Published: April 2011

Major histocompatibility complex (MHC) class II-presented peptides can be derived from both exogenous (extracellular) and endogenous (biosynthesized) sources of antigen. Although several endogenous antigen-processing pathways have been reported, little is known about their relative contributions to global CD4+T cell responses against complex antigens. Using influenza virus for this purpose, we assessed the role of macroautophagy, a process in which cytosolic proteins are delivered to the lysosome byde novovesicle formation and membrane fusion. Influenza infection triggered productive macroautophagy, and autophagy-dependent presentation was readily observed with model antigens that naturally traffic to the autophagosome. Furthermore, treatments that enhance or inhibit macroautophagy modulated the level of presentation from these model antigens. However, validated enzyme-linked immunospot (ELISpot) assays of influenza-specific CD4+T cells from infected mice using a variety of antigen-presenting cells, including primary dendritic cells, revealed no detectable macroautophagy-dependent component. In contrast, the contribution of proteasome-dependent endogenous antigen processing to the global influenza CD4+response was readily appreciated. The contribution of macroautophagy to the MHC class II-restricted response may vary depending upon the pathogen.
Varicella-Zoster Virus (VZV) Infection of Neurons Derived from Human Embryonic Stem Cells: Direct Demonstration of Axonal Infection, Transport of VZV, and Productive Neuronal Infection
Authors: Markus Amos , Grigoryan Sergei , Sloutskin Anna , Yee Michael B. , Zhu Hua , Yang In Hong , Thakor Nitish V. , Sarid Ronit , Kinchington Paul R. , Goldstein Ronald S.
Published: April 2011

Study of the human neurotrophic herpesvirus varicella-zoster virus (VZV) and of its ability to infect neurons has been severely limited by strict viral human tropism and limited availability of human neurons for experimentation. Human embryonic stem cells (hESC) can be differentiated to all the cell types of the body including neurons and are therefore a potentially unlimited source of human neurons to study their interactions with human neurotropic viruses. We report here reproducible infection of hESC-derived neurons by cell-associated green fluorescent protein (GFP)-expressing VZV. hESC-derived neurons expressed GFP within 2 days after incubation with mitotically inhibited MeWo cells infected with recombinant VZV expressing GFP as GFP fusions to VZV proteins or under an independent promoter. VZV infection was confirmed by immunostaining for immediate-early and viral capsid proteins. Infection of hESC-derived neurons was productive, resulting in release into the medium of infectious virions that appeared fully assembled when observed by electron microscopy. We also demonstrated, for the first time, VZV infection of axons and retrograde transport from axons to neuronal cell bodies using compartmented microfluidic chambers. The use of hESC-derived human neurons in conjunction with fluorescently tagged VZV shows great promise for the study of VZV neuronal infection and axonal transport and has potential for the establishment of a model for VZV latency in human neurons.
P Bodies Inhibit Retrotransposition of Endogenous Intracisternal A Particles
Authors: Lu Chunye , Contreras Xavier , Peterlin B. Matija
Published: April 2011

mRNA-processing bodies (P bodies) are cytoplasmic foci that contain translationally repressed mRNA. Since they are important for the retrotransposition of Ty elements and brome mosaic virus in yeast cells, we assessed the role of P bodies in the movement of endogenous intracisternal A particles (IAPs) in mammalian cells. In contrast to the case for these other systems, their disruption via knockdown of RCK or eukaryotic initiation factor E transporter (eIF4E-T) increased IAP retrotransposition as well as levels of IAP transcripts, Gag proteins, and reverse transcription products. This increase was not mediated by impairing the microRNA pathway. Rather, the removal of P bodies shifted IAP mRNA from nonpolysomal to polysomal fractions. Although IAP mRNA localized to P bodies, Gag was targeted to the endoplasmic reticulum (ER), from which IAP buds. Thus, by sequestering IAP mRNA away from Gag, P bodies inhibit rather than promote IAP retrotransposition.
Human Herpesvirus 6 Suppresses T Cell Proliferation through Induction of Cell Cycle Arrest in Infected Cells in the G
2
/M Phase
Authors: Li Lingyun , Gu Bin , Zhou Feng , Chi Jing , Wang Fang , Peng Guangyong , Xie Fangyi , Qing Jian , Feng Dongju , Lu Shiqiang , Yao Kun
Published: April 2011

Human herpesvirus 6 (HHV-6) is an important immunosuppressive and immunomodulatory virus that primarily infects immune cells and strongly suppresses the proliferation of infected cells. However, the mechanisms responsible for the regulation and suppression mediated by HHV-6 are still unknown. In this study, we examined the ability of HHV-6A to manipulate cell cycle progression in infected cells and explored the potential molecular mechanisms. We demonstrated that infection with HHV-6A imposed a growth-inhibitory effect on HSB-2 cells by inducing cell cycle arrest at the G
2
/M phase. We then showed that the activity of the Cdc2–cyclin B1 complex was significantly decreased in HHV-6A-infected HSB-2 cells. Furthermore, we found that inactivation of Cdc2–cyclin B1 in HHV-6A-infected cells occurred through the inhibitory Tyr15 phosphorylation resulting from elevated Wee1 expression and inactivated Cdc25C. The reduction of Cdc2–cyclin B1 activity in HHV-6-infected cells was also partly due to the increased expression of the cell cycle-regulatory molecule p21 in a p53-dependent manner. In addition, HHV-6A infection activated the DNA damage checkpoint kinases Chk2 and Chk1. Our data suggest that HHV-6A infection induces G
2
/M arrest in infected T cells via various molecular regulatory mechanisms. These results further demonstrate the potential mechanisms involved in immune suppression and modulation mediated by HHV-6 infection, and they provide new insights relevant to the development of novel vaccines and immunotherapeutic approaches.
The Conserved YAGL Motif in Human Metapneumovirus Is Required for Higher-Order Cellular Assemblies of the Matrix Protein and for Virion Production
Authors: Sabo Yosef , Ehrlich Marcelo , Bacharach Eran
Published: April 2011

YXXL motifs in cellular and viral proteins have a variety of functions. The matrix (M) protein of the respiratory pathogen human metapneumovirus (hMPV) contains two such conserved motifs—YSKL and YAGL. We mutated these sequences to analyze their contributions to hMPV infectivity. The mutant clones were capable of intracellular replication; however, the YAGL but not YSKL mutants were defective at spreading in infected cultures. We improved the reverse genetics system for hMPV and generated cell lines that stably expressed selectable, replicating full-length genomes for both the wild type and the mutant clones, allowing microscopic and biochemical analyses of these viruses. YAGL mutants produced normal cellular levels of M protein but failed to release virions, while ectopic coexpression of wild-type M generated particles that were restricted to a single cycle of infection. The YAGL motif did not act as a late (L) domain, however, since hMPV budding was independent of the cellular endosomal sorting complex required for transport (ESCRT) machinery and because replacement of the YAGL motif with classical L domains generated defective viruses. Instead, the YAGL mutants had defective M assemblies lacking a normal filamentous appearance and showed poor extractability from the cell compared to the wild-type protein. The mutant proteins were not grossly misfolded, however, as they interacted with cellular membranes and coassembled with wild-type M proteins. Thus, the YAGL motif is an important determinant of hMPV assembly. Furthermore, the selectable hMPV genomes described here should extend the use of reverse genetics systems in the analysis of spreading-defective viruses.
CONVENTIONAL ECONOMIC THEORY — A CRITIQUE HIGHLIGHTING FLAWS IN AMERICAN STYLE CAPITALISM
Authors: MOELLER JOERGEN OERSTROEM
Published: April 2011

For 200 years, we have lived with capitalism in its American style forged easy access to raw materials. Despite entering an era of scarcities, economics is still anchored in growth and distribution theories reflecting the world of plenty. Production theory does not recognize the significance of sharing of knowledge and group behavior introduced by ICT. Consumption theory is still about buying 'more', neglecting the element of uncertainty. Competition has been eradicated and replaced by a limited number of gigantic corporations. Only recently has economics started to go interdisciplinary to incorporate psychology and brain research to explain behavior when confronted with economic choices and the difference between individual and group behavior.
GOVERNMENT FISCAL BEHAVIOR AND ECONOMIC GROWTH OF SINGAPORE IN THE TWENTIETH CENTURY
Authors: SUGIMOTO ICHIRO , TAN EU CHYE
Published: April 2011

This paper reviews the trends in the government fiscal structure and explores the possible relationships between government fiscal expenditure and economic growth in Singapore over the 20th century. It is a reasonable conjecture that the government fiscal behavior and in particular vis-à-vis economic growth had undergone a significant shift as Singapore switched from British colonial rule to self-government. The paper first traces out the characteristics of the colonial government fiscal behavior and compares them with those during the period of self-government in terms of sources and uses of revenue and fiscal balance. This is then followed by econometric exercises to ascertain whether the government fiscal expenditure responds to income movements broadly in the spirit of Wagner's law in 1900–1939 and 1966–2000. Generally, attention is focused upon inter-temporal similarities and differences.
MODEL AND VERIFICATION OF WS-CDL BASED ON UML DIAGRAMS
Authors: ZHANG PENGCHENG , MUCCINI HENRY , ZHU YUELONG , LI BIXIN
Published: April 2011

The Web Services Choreography Description Language (WS-CDL) is a specification developed by the W3C and can be viewed as a blueprint for the development of end-point services. Consequently, it is worth providing a systematic approach for its modeling, analysis and verification. The Unified Modeling Language (UML) is an industry standard for modeling. Applying UML to model WS-CDL is obviously a promising solution to bring together academics and practitioners through a unique standard language. In this paper, we propose to use different UML diagrams to model WS-CDL. UML Component Diagram is used to model the underlying structure of WS-CDL. UML Sequence Diagram is utilized to model the activities in WS-CDL. UML State Machine Diagram is utilized to model the behaviors of each role participating in a WS-CDL specification. We then enrich the UML State Machine Diagram with data by the use of UML Class Diagram. Given the UML specification of WS-CDL, we then provide a systematic way of formally analyzing and verifying WS-CDL against desired properties. Some experiments show that our approach can verify structural, behavioral and data properties in a middle-scale data-enriched WS-CDL specification.
GAUSS DIAGRAM INVARIANTS OF LINKS IN M2 × R1
Authors: GRISHANOV S. A. , VASSILIEV V. A.
Published: April 2011

We construct an infinite series of invariants of Fiedler type (i.e. composed of oriented arrow diagrams arranged by elements of H1(M3)) for multicomponent links in M3 = M2 × R1, M2 orientable with π1(M2) ≠ {1}.
SELF-INTERSECTION NUMBERS OF PATHS IN COMPACT SURFACES
Authors: ARMAS-SANABRIA LORENA , GONZÁLEZ-ACUÑA FRANCISCO , RODRÍGUEZ-VIORATO JESÚS
Published: April 2011

In this paper, we give an algorithm to calculate the minimal self-intersection number of paths in a compact surface with boundary representing a given element of the free group F(x1, x2, …, xn). In particular, this algorithm says whether or not a word in x1, x2, …, xn is representable by a simple path. Our algorithm is simpler than similar algorithms given previously. In the case of a disk with n holes the problem is equivalent to the problem of deciding which relators can appear in an Artin n-presentation.
PERIODIC ORBITS OF A DYNAMICAL SYSTEM RELATED TO A KNOT
Authors: LYUBICH LILYA
Published: April 2011

Following [6] we consider a knot group G, its commutator subgroup K = [G, G], a finite group Σ and the space Hom (K, Σ) of all representations ρ : K → Σ, endowed with the weak topology. We choose a meridian x ∈ G of the knot and consider the homeomorphism σx of Hom (K, Σ) onto itself: σxρ(a) = ρ(xax-1) ∀ a ∈ K, ρ ∈ Hom (K, Σ). As proven in [5], the dynamical system ( Hom (K, Σ), σx) is a shift of finite type. In the case when Σ is abelian, Hom (K, Σ) is finite.

In this paper we calculate the periods of orbits of ( Hom (K, ℤ/p), σx), where p is prime, in terms of the roots of the Alexander polynomial of the knot. In the case of two-bridge knots we give a complete description of the set of periods.
THE JONES POLYNOMIAL AND THE INTERSECTION NUMBERS OF TWISTED CYCLES ASSOCIATED WITH A SELBERG TYPE INTEGRAL
Authors: MIMACHI KATSUHISA
Published: April 2011

We give a new definition of the Jones polynomial by means of the intersection number of loaded (or twisted) cycles associated with a Selberg type integral. Our definition is naturally formulated in the framework of the twisted homology theory, which is developd by Aomoto to study the special functions of hypergeometric type. The naturality of the definition leads to evaluate the Jones polynomials in several cases: well-known results in the case of two-bridge link, a formula for (3, s)-torus and that for the Prezel with 3 parameters. Our definition is motivated by the work of Bigelow.
PATELLA TRACKING WITH PERIPATELLAR SOFT TISSUE STABILIZERS AS A FUNCTION OF DYNAMIC SUBJECT-SPECIFIC KNEE FLEXION
Authors: MÜLLER J. H. , SCHEFFER C. , ELVIN A. , ERASMUS P. J. , DILLON E. M.
Published: April 2011

Musculoskeletal modeling has found wide application in joint biomechanics investigations. This technique has been improved by incorporating subject-specific skeletal elements and passive patellofemoral stabilizers in a dynamic analysis. After trochlear engagement, the volunteers' patellae displaced laterally, whereas tilt was subject specific. Comparison of the tilt and mediolateral position values to in vivo MRI values at 30° knee flexion showed a mean accuracy of 84.4% and 96.9%, respectively. Medial patellofemoral ligament tension decreased with knee flexion, while the patellar tendon–quadriceps tendon ratio ranged from 0.4 to 1.2. The patellofemoral contact load–quadriceps tendon load ratio ranged from 0.7 to 1.3, whereas the mediolateral load component–resultant load ratio ranged from 0 to 0.4. Three validated subject-specific musculoskeletal models facilitated the analysis of patellofemoral biomechanics: Subject-specific patella tracking and passive stabilizer response was analyzed as a function of dynamic knee flexion.
THE UTOPIAN GOAL OF ATTEMPTING TO DELIVER ENVIRONMENTAL JUSTICE USING SEA
Authors: MCLAUCHLAN ANNA , JOÃO ELSA
Published: April 2011

Environmental justice is a contested concept. However, it became a high-level policy objective in the United States and, internationally, policy advocates and academics have identified environmental justice as a fundamental part of sustainable development. Policy appraisal, in particular Strategic Environmental Assessment (SEA), has been cited as a main tool to deliver environmental justice policy. Scotland, a devolved government within the UK, made a high-level policy commitment to environmental justice and linked its delivery to SEA. To evaluate how this was put into practice, this paper analyses Scottish SEA documents produced between 2003 and 2007. The study found that SEA practice in Scotland was not directed towards empirical assessment of environmental justice. More fundamentally, because assessments always reflect specific values, there is no incontestable way to represent environmental justice or injustice empirically. Therefore, this paper argues that environmental justice remains a Utopian goal, with no indisputable means to be achieved.
INTRINSIC FLUORESCENCE CHANGES IN NERVE TERMINALS, EVOKED BY ACTION POTENTIALS, ARE MODULATED BY KREBS CYCLE SUBSTRATES
Authors: KOSTERIN PAUL , OBAID ANA LÍA , SALZBERG BRIAN M.
Published: April 2011

Electrical stimulation of the mammalian neurohypophysial infundibular stalk evokes the entry of Na+and Ca2+into the neurosecretory terminals during the action potential. These events, in turn, increase intracellular Ca2+and activate NaK - and Ca -ATPases, prompting the mitochondria to increase oxidative phosphorylation which can be monitored by recording the changes in FAD and NADH fluorescence. This paper reflects our efforts to determine whether or not modulating the capacity of mitochondria to produce ATP, by changing the concentrations of two important substrates of the Krebs cycle of the nerve terminal mitochondria, pyruvate and glucose, has an effect on the intrinsic fluorescence changes triggered by action potential stimulation.
NEAR-INFRARED IMAGING SENSOR WITH IMPROVED HANDLING AND DIRECT LOCALIZATION IN SIMULTANEOUS MAGNETIC RESONANCE IMAGING MEASUREMENTS
Authors: SPICHTIG SONJA , PICCIRELLI MARCO , VORBURGER ROBERT S. , WOLF MARTIN
Published: April 2011

We present a novel optical sensor to acquire simultaneously functional near-infrared imaging (fNIRI) and functional magnetic resonance imaging (fMRI) data with an improved handling and direct localization in the MRI compared to available sensors. Quantitative phantom and interference measurements showed that both methods can be combined without reciprocal adverse effects. The direct localization of the optical sensor on MR images acquired with a T1-weighted echo sequence simplifies the co-registration of NIRI and MRI data. In addition, the optical sensor is simple to attach, which is crucial for measurements on vulnerable subjects. The fNIRI and T2*-weighted fMRI data of a cerebral activation were simultaneously acquired proving the practicability of the setup.
Homogeneous accelerometer-based sensor networks for game interaction
Authors: Whitehead Anthony , Johnston Hannah , Fox Kaitlyn , Crampton Nick , Tuen Joe
Published: April 2011

We have created and tested a wearable sensor network that detects a user's body position and motion as input for interactive applications. It is envisioned to take game experiences such as Dance Dance Revolution, Wii Fit, and other active play scenarios to a whole new level, augmenting or replacing the binary foot-pad and balance board with a more immersive, full-body input system. We describe the design and functionality of the sensor network to characterize and verify body pose and position, perform experiments, and report on the capabilities and limitations of such a system. Our experience shows that a distributed set of sensors around the body prevents the player from cheating the system by using motion of the device alone to trick the system. In this work we show that a relatively simple sensor network configuration can enforce proper form and ensure that the player is actively participating in the game context, while a larger configuration can be used in training applications.