bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of Results of Detection of Rhinovirus by PCR and Viral Culture in Human Nasal Wash Specimens from Subjects with and without Clinical Symptoms of Respiratory Illness
Authors: Wright Peter F. , Deatly Anne M. , Karron Ruth A. , Belshe Robert B. , Shi Jian R. , Gruber William C. , Zhu Yuwei , Randolph Valerie B. 
Published: May 2007

ABSTRACT
Human rhinoviruses (HRV) cause acute upper respiratory illness. The frequency of HRV-associated illnesses appears greater when PCR assays are used to detect rhinoviruses. The present study performed PCR-based detection of HRV upon entry of subjects into respiratory syncytial virus and parainfluenza type 3 vaccine trials when subjects were symptom-free and upon subsequent development of clinical symptoms of respiratory illness during the trial. The background of HRV PCR positivity in symptom-free individuals (30/139 [22%]) was only slightly lower than in those with respiratory illness (28/77 [36%]). For subjects with multiple samples, it was estimated that HRV was detectable by PCR for approximately 100 days before, during, and after clinical symptoms were documented. PCR is a remarkably more sensitive method of detecting HRV than is tissue culture. The presence of HRV RNA may not always reflect an association with infectious virus production. The limited association of HRV RNA with illness suggests caution in assigning causality of HRV PCR positivity to clinical symptoms of respiratory illness.
Chloroviruses Encode a Bifunctional dCMP-dCTP Deaminase That Produces Two Key Intermediates in dTTP Formation
Authors: Zhang Yuanzheng , Maley Frank , Maley Gladys F. , Duncan Garry , Dunigan David D. , Van Etten James L. 
Published: May 2007

ABSTRACT
The chlorovirus PBCV-1, like many large double-stranded DNA-containing viruses, contains several genes that encode putative proteins involved in nucleotide biosynthesis. This report describes the characterization of the PBCV-1 dCMP deaminase, which produces dUMP, a key intermediate in the synthesis of dTTP. As predicted, the recombinant protein has dCMP deaminase activity that is activated by dCTP and inhibited by dTTP. Unexpectedly, however, the viral enzyme also has dCTP deaminase activity, producing dUTP. Typically, these two reactions are catalyzed by proteins in separate enzyme classes; to our knowledge, this is the first example of a protein having both deaminase activities. Kinetic experiments established that (i) the PBCV-1 enzyme has a higher affinity for dCTP than for dCMP, (ii) dCTP serves as a positive heterotropic effector for the dCMP deaminase activity and a positive homotropic effector for the dCTP deaminase activity, and (iii) the enzymatic efficiency of the dCMP deaminase activity is about four times higher than that of the dCTP deaminase activity. Inhibitor studies suggest that the same active site is involved in both dCMP and dCTP deaminations. The discovery that the PBCV-1 dCMP deaminase has two activities, together with a previous report that the virus also encodes a functional dUTP triphosphatase (Y. Zhang, H. Moriyama, K. Homma, and J. L. Van Etten, J. Virol. 79:9945-9953, 2005), means that PBCV-1 is the first virus to encode enzymes involved in all three known pathways to form dUMP.
Sensitive Assays for Simian Foamy Viruses Reveal a High Prevalence of Infection in Commensal, Free-Ranging Asian Monkeys
Authors: Jones-Engel Lisa , Steinkraus Katherine A. , Murray Shannon M. , Engel Gregory A. , Grant Richard , Aggimarangsee Nantiya , Lee Benjamin P. Y.-H. , May Cynthia , Schillaci Michael A. , Somgird Chaleamchat , Sutthipat Tulyawat , Vojtech Lucia , Zhao JianYuan , Linial Maxine L. 
Published: May 2007

ABSTRACT
Foamy viruses (FV) are retroviruses that naturally infect many hosts, including most nonhuman primates (NHPs). Zoonotic infection by primate FV has been documented in people in Asia who reported contact with free-ranging macaques. FV transmission in Asia is a concern, given abundant human-NHP contact, particularly at monkey temples and in urban settings. We have developed three assays capable of detecting the presence of FV in Asian NHP species that are commensal with humans: enzyme-linked immunosorbent assay (ELISA), Western blot assays using recombinant viral Gag protein, and an indicator cell line that can detect macaque FV. The recombinant ELISA correlates very well with the presence of FV sequences detected by PCR. We have used these assays to demonstrate both that FV is highly prevalent among free-ranging NHPs and that seroconversion occurs at a young age in these animals. These assays should also prove useful for large-scale analysis of the prevalence of FV infections in human populations in Asia that are commensal with free-ranging NHPs.
A Novel Bcl-2-Like Inhibitor of Apoptosis Is Encoded by the Parapoxvirus Orf Virus
Authors: Westphal Dana , Ledgerwood Elizabeth C. , Hibma Merilyn H. , Fleming Stephen B. , Whelan Ellena M. , Mercer Andrew A. 
Published: May 2007

ABSTRACT

Apoptotic cell death forms part of the host defense against virus infection. We tested orf virus, a member of the poxvirus family, for the ability to inhibit apoptosis and found that orf virus-infected cells were fully resistant to UV-induced changes in cell morphology, caspase activation, and DNA fragmentation. By using a library of vaccinia virus-orf virus recombinants, we identified an orf virus gene (
ORFV125
) whose presence was linked with the inhibition of apoptosis. The 173-amino-acid predicted protein had no clear homologs in public databases other than those encoded by other parapoxviruses. However, ORFV125 possessed a distinctive C-terminal domain which was necessary and sufficient to direct the protein to the mitochondria. We determined that ORFV125 alone could fully inhibit UV-induced DNA fragmentation, caspase activation, and cytochrome
c
release and that its mitochondrial localization was required for its antiapoptotic function. In contrast, ORFV125 did not prevent UV-induced activation of c-Jun NH
2
-terminal kinase, an event occurring upstream of the mitochondria. These features are comparable to the antiapoptotic properties of the mitochondrial regulator Bcl-2. Furthermore, bioinformatic analyses revealed sequence and secondary-structure similarities to Bcl-2 family members, including characteristic residues of all four Bcl-2 homology domains. Consistent with this, the viral protein inhibited the UV-induced activation of the proapoptotic Bcl-2 family members Bax and Bak. ORFV125 is the first parapoxvirus apoptosis inhibitor to be identified, and we propose that it is a new antiapoptotic member of the Bcl-2 family.
A Single Amino Acid of the Human Immunodeficiency Virus Type 2 Capsid Affects Its Replication in the Presence of Cynomolgus Monkey and Human TRIM5αs
Authors: Song Haihan , Nakayama Emi E. , Yokoyama Masaru , Sato Hironori , Levy Jay A. , Shioda Tatsuo 
Published: May 2007

ABSTRACT
Human immunodeficiency virus type 2 (HIV-2) strains vary widely in their abilities to grow in Old World monkey (OWM) cells such as those of cynomolgus monkeys (CM). We evaluated eight HIV-2 isolates for their sensitivities to CM TRIM5α, an anti-HIV factor in OWM cells. We found that different HIV-2 isolates showed differences in their sensitivities to CM TRIM5α. Sequence analysis showed that TRIM5α-sensitive viruses had proline at the 120th position of the capsid protein (CA), whereas TRIM5α-resistant viruses had either alanine or glutamine. Mutagenesis studies indicated that the single amino acid at the 120th position indeed affected the sensitivity of the virus to CM TRIM5α.
Novel Strategy for Treatment of Viral Central Nervous System Infection by Using a Cell-Permeating Inhibitor of c-Jun N-Terminal Kinase
Authors: Beckham J. David , Goody Robin J. , Clarke Penny , Bonny Christophe , Tyler Kenneth L. 
Published: May 2007

ABSTRACTViral encephalitis is a major cause of morbidity and mortality worldwide, yet there is no proven efficacious therapy for most viral infections of the central nervous system (CNS). Many of the viruses that cause encephalitis induce apoptosis and activate c-Jun N-terminal kinase (JNK) following infection. We have previously shown that reovirus infection of epithelial cell lines activates JNK-dependent apoptosis. We now show that reovirus infection resulted in activation of JNK and caspase-3 in the CNS. Treatment of reovirus-infected mice with a cell-permeating peptide that competitively inhibits JNK activity resulted in significantly prolonged survival of intracerebrally infected mice following an otherwise lethal challenge with T3D (100× 50% lethal dose). Protection correlated with reduced CNS injury, reduced neuronal apoptosis, and reduced c-Jun activation without altering the viral titer or viral antigen distribution. Given the efficacy of the inhibitor in protecting mice from viral encephalitis, JNK inhibition represents a promising and novel treatment strategy for viral encephalitis.
Cytokine-Independent Upregulation of MDA5 in Viral Infection
Authors: Yount Jacob S. , Moran Thomas M. , López Carolina B. 
Published: May 2007

ABSTRACT
The RNA helicases RIG-I and MDA5 detect virus infection of dendritic cells (DCs) leading to cytokine induction. Maximal sensitivity for virus detection by these helicases is obtained after their upregulation, which is thought to occur primarily through type I interferon (IFN) signaling. Here we demonstrate that in response to paramyxovirus infection, RIG-I upregulation requires type I IFN whereas MDA5 expression is increased by Sendai virus infection independently of signaling mediated by type I IFN, STAT1, tumor necrosis factor alpha, or NF-κB. This MDA5 upregulation is largely lost in IRF3 knockout DCs and is achieved in type I IFN-deficient cells expressing constitutively active IRF3.
An RNA Stem-Loop within the Bovine Coronavirus nsp1 Coding Region Is a
cis
-Acting Element in Defective Interfering RNA Replication
Authors: Brown Cary G. , Nixon Kimberley S. , Senanayake Savithra D. , Brian David A. 
Published: May 2007

ABSTRACT

Higher-order
cis
-acting RNA replication structures have been identified in the 3′- and 5′-terminal untranslated regions (UTRs) of a bovine coronavirus (BCoV) defective interfering (DI) RNA. The UTRs are identical to those in the viral genome, since the 2.2-kb DI RNA is composed of only the two ends of the genome fused between an internal site within the 738-nucleotide (nt) 5′-most coding region (the nsp1, or p28, coding region) and a site just 4 nt upstream of the 3′-most open reading frame (ORF) (the N gene). The joined ends of the viral genome in the DI RNA create a single continuous 1,635-nt ORF, 288 nt of which come from the 738-nt nsp1 coding region. Here, we have analyzed features of the 5′-terminal 288-nt portion of the nsp1 coding region within the continuous ORF that are required for DI RNA replication. We observed that (i) the 5′-terminal 186 nt of the nsp1 coding region are necessary and sufficient for DI RNA replication, (ii) two
Mfold
-predicted stem-loops within the 186-nt sequence, named SLV (nt 239 to 310) and SLVI (nt 311 to 340), are supported by RNase structure probing and by nucleotide covariation among closely related group 2 coronaviruses, and (iii) SLVI is a required higher-order structure for DI RNA replication based on mutation analyses. The function of SLV has not been evaluated. We conclude that SLVI within the BCoV nsp1 coding region is a higher-order
cis
-replication element for DI RNA and postulate that it functions similarly in the viral genome.
Maturation of Blood-Derived Dendritic Cells Enhances Human Immunodeficiency Virus Type 1 Capture and Transmission
Authors: Izquierdo-Useros Nuria , Blanco Julià , Erkizia Itziar , Fernández-Figueras Maria Teresa , Borràs Francesc E. , Naranjo-Gómez Mar , Bofill Margarita , Ruiz Lidia , Clotet Bonaventura , Martinez-Picado Javier 
Published: May 2007

ABSTRACT

Dendritic cells (DCs) are specialized antigen-presenting cells. However, DCs exposed to human immunodeficiency virus type 1 (HIV-1) are also able to transmit a vigorous cytopathic infection to CD4
+
T cells, a process that has been frequently related to the ability of DC-SIGN to bind HIV-1 envelope glycoproteins. The maturation of DCs can increase the efficiency of HIV-1 transmission through
trans
infection. We aimed to comparatively study the effect of maturation in monocyte-derived DCs (MDDCs) and blood-derived myeloid DCs during the HIV-1 capture process. In vitro capture and transmission of envelope-pseudotyped HIV-1 and its homologous replication-competent virus to susceptible target cells were assessed by p24
gag
detection, luciferase activity, and both confocal and electron microscopy. Maturation of MDDCs or myeloid DCs enhanced the active capture of HIV-1 in a DC-SIGN- and viral envelope glycoprotein-independent manner, increasing the life span of trapped virus. Moreover, higher viral transmission of mature DCs to CD4
+
T cells was highly dependent on active viral capture, a process mediated through cholesterol-enriched domains. Mature DCs concentrated captured virus in a single large vesicle staining for CD81 and CD63 tetraspanins, while immature DCs lacked these structures, suggesting different intracellular trafficking processes. These observations help to explain the greater ability of mature DCs to transfer HIV-1 to T lymphocytes, a process that can potentially contribute to the viral dissemination at lymph nodes in vivo, where viral replication takes place and there is a continuous interaction between susceptible T cells and mature DCs.
Primary Cell Model for Activation-Inducible Human Immunodeficiency Virus
Authors: Burke Bryan , Brown Helen J. , Marsden Matthew D. , Bristol Gregory , Vatakis Dimitrios N. , Zack Jerome A. 
Published: May 2007

ABSTRACT

Quiescent T lymphocytes containing latent human immunodeficiency virus (HIV) provide a long-lived viral reservoir. This reservoir may be the source of active infection that is reinitiated following the cessation of antiretroviral therapy. Therefore, it is important to understand the mechanisms involved in latent infection to develop new strategies to eliminate the latent HIV reservoir. We have previously demonstrated that latently infected quiescent lymphocytes can be generated during thymopoiesis in vivo in the SCID-hu mouse system. However, there is still a pressing need for an in vitro model of HIV latency in primary human cells. Here, we present a novel in vitro model that recapitulates key aspects of dormant HIV infection. Using an enhanced green fluorescent protein-luciferase fusion protein-containing reporter virus, we have generated a stable infection in primary human CD4
+
CD8
+
thymocytes in the absence of viral gene expression. T-cell activation induces a >200-fold induction of reporter activity. The induced reporter activity originates from a fully reverse-transcribed and integrated genome. We further demonstrate that this model can be useful to study long terminal repeat regulation, as previously characterized NF-κB response element mutations decrease the activation of viral gene expression. This model can therefore be used to study intricate molecular aspects of activation-inducible HIV infection in primary cells.
Relationship between blood pressure and blood flow in newborn preterm infants
Authors: Groves A M , Kuschel C A , Knight D B , Skinner J R 
Published: May 2007

Background:Arterial blood pressure remains the most frequently monitored indicator of neonatal circulatory status. However, studies of systemic perfusion in neonates have often shown only weakly positive associations with blood pressure.Objectives:To examine the relationship between invasively monitored arterial blood pressure and four measurements of systemic perfusion: left and right ventricular outputs, superior vena caval (SVC) flow and descending aortic (DAo) flow.Design:Echocardiographic assessments of perfusion were performed four times in the first 48 h of postnatal life in a cohort of 34 preterm (<30 weeks) infants. Arterial blood pressure was monitored invasively over the exact duration of the echocardiogram.Results:In the first 48 h of postnatal life there was no evidence of a positive association between blood pressure and volume of blood flow in any of the four vessels studied. At 5 h postnatal age there was a weak but significant inverse correlation between volume of SVC flow and arterial blood pressure (p = 0.04). A similar but non-significant trend was seen at 12 h postnatal age.Conclusions:Infants with reduced systemic perfusion tend to have normal or high blood pressure in the first hours of life, suggesting that a high systemic vascular resistance may lead to reduced blood flow. Low blood pressure does not correlate with poor perfusion in the first 48 h of postnatal life in sick preterm infants.
Rectangular Structure in My Montage Paintings
Authors: Bearden Romare 
Published: May 2007

The author describes his change from being a student of mathematics to that of being a painter, after studying with George Grosz. Through Grosz, the author was led to study Brueghel, and the Dutch masters and their art, together with Byzantine mosaics and African sculpture, have remained a major influence in his work. A study of the paintings of De Hooch and Vermeer was also helpful from the point of view of the way those artists were able to control their large shapes, even when disparate elements were included within these shapes. Also, the author describes the influence upon him of examples of Chinese paintings and his method of working with mounted layers of torn papers. Both the similarities as well as the differences to Cubism in his style are described in detail, with the hope that the structural content of his work will be understood and even more valued than its social message.
Acceptable ungrammaticality in sentence matching
Authors: Duffield Nigel , Matsuo Ayumi , Roberts Leah 
Published: May 2007

This article presents a new set of experiments using the sentence-matching paradigm (Forster, 1979; Freedman and Forster, 1985; see also Bley-Vroman and Masterson, 1989), investigating native speakers' and second language (L2) learners' knowledge of constraints on clitic placement in French. Our purpose is three-fold: • to shed more light on the contrasts between native speakers and L2 learners observed in previous experiments, especially Duffield and White (1999), and Duffield et al . (2002); • to address some of the specific criticisms of the sentence-matching paradigm levelled by Gass (2001); and • to provide a firm empirical basis for follow-up experiments with L2 learners. The results reported here provide some confirmation of the validity of Duffield et al.'s earlier work, and help to adjudicate among competing interpretations of the previous effects.
On Making Them All One: Unity, Transcendence and the Anglican Church
Authors: Baker Anthony D. 
Published: May 2007

ABSTRACTThe question of unity looms large in current vocabulary of the Anglican Communion. This article suggests, first of all, that the term is a rich theological one that ought to come under rigorous theological scrutiny and, secondly, that such scrutiny could in fact alter the way Anglicans understand themselves as an ecclesial body. While the works of Rowan Williams and Ephraim Radner have issued important and necessary calls for a return to ecclesiology, both, it is here suggested, do not illuminate fully the implications of the New Testament call to ‘be one’. Making substantial reference to Hooker's theology of the church, which is properly seen as an extension of his Christology, it is here suggested that unity is both a gift that transcends the church in its descent in the Spirit, and a craft that takes shape as the church struggles to make and remake itself in the image of Christ, whose prayer that his followers would all be one as ‘you and I’ is one that has consistently supplied the framework for the tradition of Christian ecclesiology.
Reintroduction of C/EBPα in leukemic CD34+ stem/progenitor cells impairs self-renewal and partially restores myelopoiesis
Authors: Schepers Hein , Wierenga Albertus T. J. , van Gosliga Djoke , Eggen Bart J. L. , Vellenga Edo , Schuringa Jan Jacob 
Published: May 2007

Abstract
The CCAAT/enhancer binding protein (C/EBP) α transcription factor is indispensable for myeloid differentiation. In various myeloid leukemias, C/EBPα is mutated or functionally impaired due to decreased C/EBPα expression or phosphorylation. In order to investigate the functional consequences of decreased C/EBPα function in AML, we reintroduced C/EBPα in primary CD34+ sorted acute myeloid leukemia (AML) cells using a lentiviral approach. Self-renewal and differentiation of primary AML stem cells were studied on long-term MS5 cocultures. Activation of C/EBPα immediately led to a growth arrest in all AML cultures (N = 7), resulting in severely reduced expansion compared with control cultures. This growth arrest corresponded with enhanced myeloid differentiation as assessed by fluorescence-activated cell sorter (FACS) analysis for CD14, CD15, and CD11b. Myeloid differentiation was further confirmed by the up-regulation of neutrophil elastase and granulocyte colony-stimulating factor (G-CSF) receptor in C/EBPα transduced cells. C/EBPα-expressing AML CD34+ cells failed to generate second and third leukemic cobblestone areas (L-CAs) in serial replating experiments, while control cultures could be sequentially passaged for more than 4 times, indicating that reintroduction of C/EBPα impaired the self-renewal capacity of the leukemic CD34+ compartment. Together, our data indicate that low C/EBPα levels are necessary to maintain self-renewal and the immature character of AML stem cells.
Immunologic evidence for lack of heterologous protection following resolution of HCV in patients with non–genotype 1 infection
Authors: Schulze zur Wiesch Julian , Lauer Georg M. , Timm Joerg , Kuntzen Thomas , Neukamm Martin , Berical Andrew , Jones Andrea M. , Nolan Brian E. , Longworth Steve A. , Kasprowicz Victoria , McMahon Cory , Wurcel Alysse , Lohse Ansgar W. , Lewis-Ximenez Lia L. , Chung Raymond T. , Kim Arthur Y. , Allen Todd M. , Walker Bruce D. 
Published: May 2007

AbstractChronic hepatitis C virus (HCV) infection is typically characterized by a lack of virus-specific CD4+ T-cell–proliferative responses, but strong responses have been described in a subset of persons with persistent viremia. One possible explanation for these responses is that they were primed by an earlier resolved infection and do not recognize the current circulating virus. We defined all targeted epitopes using overlapping peptides corresponding to a genotype 1a strain in 44 patients chronically infected with different HCV genotypes (GT). Surprisingly, more HCV-specific CD4+ T-cell responses were detected in patients with chronic non-GT1 infection compared with patients with chronic GT1 infection (P = .017). Notably, we found serologic evidence of a previous exposure to GT1 in 4 patients with non-GT1 infection, and these persons also demonstrated significantly more responses than non-GT1 patients in whom genotype and HCV serotype were identical (P < .001). Comparison of recognition of GT1-specific peptides to peptides representing autologous virus revealed the absence of cross-recognition of the autologous circulating virus. These data indicate that persisent HCV infection can occur in the presence of an HCV-specific T-cell response primed against a heterologous HCV strain, and suggest that clearance of 1 GT does not necessarily protect against subsequent exposure to a second GT.