bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dynamic Response of Prevacuolar Compartments to Brefeldin A in Plant Cells
Authors: Tse Yu Chung , Lo Sze Wan , Hillmer Stefan , Dupree Paul , Jiang Liwen 
Published: October 2006

AbstractLittle is known about the dynamics and molecular components of plant prevacuolar compartments (PVCs) in the secretory pathway. Using transgenic tobacco (Nicotiana tabacum) Bright-Yellow-2 (BY-2) cells expressing membrane-anchored yellow fluorescent protein (YFP) reporters marking Golgi or PVCs, we have recently demonstrated that PVCs are mobile multivesicular bodies defined by vacuolar sorting receptor proteins. Here, we demonstrate that Golgi and PVCs have different sensitivity in response to brefeldin A (BFA) treatment in living tobacco BY-2 cells. BFA at low concentrations (5–10 μg mL−1) induced YFP-marked Golgi stacks to form both endoplasmic reticulum-Golgi hybrid structures and BFA-induced aggregates, but had little effect on YFP-marked PVCs in transgenic BY-2 cells at both confocal and immunogold electron microscopy levels. However, BFA at high concentrations (50–100 μg mL−1) caused both YFP-marked Golgi stacks and PVCs to form aggregates in a dose- and time-dependent manner. Normal Golgi or PVC signals can be recovered upon removal of BFA from the culture media. Confocal immunofluorescence and immunogold electron microscopy studies with specific organelle markers further demonstrate that the PVC aggregates are distinct, but physically associated, with Golgi aggregates in BFA-treated cells and that PVCs might lose their internal vesicle structures at high BFA concentration. In addition, vacuolar sorting receptor-marked PVCs in root-tip cells of tobacco, pea (Pisum sativum), mung bean (Vigna radiata), and Arabidopsis (Arabidopsis thaliana) upon BFA treatment are also induced to form similar aggregates. Thus, we have demonstrated that the effects of BFA are not limited to endoplasmic reticulum and Golgi, but extend to PVC in the endomembrane system, which might provide a quick tool for distinguishing Golgi from PVC for its identification and characterization, as well as a possible new tool in studying PVC-mediated protein traffic in plant cells.
Graft‐versus‐host disease in recipients of grafts from natural killer T cell‐deficient (Jα281–/–) donors
Authors: Ellison Cynthia A. , Taniguchi Masaru , Fischer Jacqie M. M. , Hayglass Kent T. , Gartner John G. 
Published: October 2006

SummaryVα14i natural killer T cells (NKT cells) are a CD1‐restricted subset of NKT cells that express an invariable Vα14+ Jα281+αβ T‐cell receptor. To determine whether the absence of Vα14i NKT cells from the graft affects the development of acute GVHD, we induced GVH reactions using Jα281–/– mice as donors in the C57BL/6→(C57BL/6 × DBA/2)F1‐hybrid strain combination. Recipients of grafts from Jα281–/– donors were not protected from either the morbidity or the severe wasting syndrome associated with the development of acute GVHD, but the concentrations of some T helper 1 (Th1) and Th2 cytokines were different from those seen in recipients of grafts from wild‐type donors. Interferon‐γ was seen earlier (day 4) in recipients of grafts from Jα281–/– donors but did not reach the concentrations seen in recipients of grafts from wild‐type donors on day 8 (P < 0·02). On day 8, the amount of tumour necrosis factor‐α released into the serum following the injection of a small amount of lipopolysaccharide was lower in recipients of grafts from Jα281–/– donors (P < 0·02). The amount of interleukin (IL)‐5 was also lower in recipients of grafts from Jα281–/– donors, when compared to the concentration seen in recipients of grafts from wild‐type donors (P < 0·002). IL‐13 was seen in recipients of grafts from Jα281–/– donors but not in recipients of grafts from wild‐type donors. Our findings show that the absence of donor Vα14i NKT cells is associated with lower concentrations of some Th1 cytokines. We also observed higher IL‐13 concentrations and lower IL‐5 concentrations in recipients of grafts from Jα281–/– donors indicating a variable effect on Th2 cytokine production.
Sigmoid orthotopic neobladder after radical cystectomy for bladder tumour: an Indian experience
Authors: Yadav Sher Singh , Sadadukhi Trilok Chand , Sharma Krishnan Kumar , Yadav Ram Gopal , Mathur Rajeev 
Published: October 2006

Authors from India describe their experience using a sigmoid orthotopic neobladder in patients who have had a radical cystectomy. They found a fairly high complication rate, with nocturnal incontinence occurring in 97% of their patients. Other complications were relatively few, and the authors felt that their sigmoid neobladder presented a valuable option for diverting urine after radical cystectomy.OBJECTIVETo determine the long‐term results of constructing a sigmoid neobladder after radical cystectomy for transitional cell carcinoma (TCC) of the urinary bladder.PATIENTS AND METHODSThe study included 170 patients with TCC of the bladder and a normal sigmoid colon. After radical cystectomy the neobladder was formed by completely detubularizing an isolated sigmoid colon segment. Subsequently patients were followed by clinical, biochemical, radiological and urodynamic assessments.RESULTSFour patients died soon after surgery; the neobladder‐related delayed complications were death in three patients, loss of five renal units, and electrolyte imbalance in five patients. Uretero‐intestinal anastomotic narrowing was another frequent delayed complication. Most (97%) patients had nocturnal incontinence, and most voided with a good stream with a minimal postvoid residual urine volume.CONCLUSIONThe sigmoid neobladder, despite some limitations, is the best option for diverting urine after radical cystectomy.
Benchmarking Australian fixed interest fund performance: finding the optimal factors
Authors: Soucik Victor , Allen David E. 
Published: October 2006

AbstractIn this paper, we analyse the performance of Australian fixed interest managed funds and assess multiple benchmarks through which such performance can be reliably measured. We examine the effectiveness of seven indices of bond performance, as well as factors impacting on fixed interest asset values and, hence, returns, including interest rate fluctuations, economic fundamentals, maturity risk, default risk and cross‐market influences. We test all combinations of factors in cross‐section and time series to find the optimum benchmark. The results, consistent across time, show that a correct combination of a fund‐based market variable, a mixture of interest rate factors and economic factors as well as a proxy for movements in the equity markets yield the optimal benchmark.
OPTIMAL MONETARY POLICY AND ASSET PRICE MISALIGNMENTS
Authors: Kontonikas Alexandros , Montagnoli Alberto 
Published: October 2006

ABSTRACTThis paper analyses the relationship between monetary policy and asset prices in the context of optimal policy rules. The transmission mechanism is represented by a linearized rational expectations model augmented for the effect of asset prices on aggregate demand. Stabilization objectives are represented by a discounted quadratic loss function penalizing inflation and output gap volatility. Asset prices are allowed to deviate from their intrinsic value due to momentum trading. We find that in the presence of wealth effects and inefficient markets, asset price misalignments from their fundamentals should be included in the optimal interest rate reaction function.
A different paradigm for expert systems: an introduction to logic programming and related knowledge representation issues
Authors: Jones James D. 
Published: October 2006

Abstract: Current expert system technology is 30 years old. Expert system shells find their origins in the work of early expert systems, most notably MYCIN which was developed at Stanford in the mid‐1970s. Even Prolog programmers are settling for less robust reasoning power. The logic programming community (from which both expert systems and Prolog arose) has made notable advances since those times. These advances are lacking from current expert system technology. The advances include a well‐developed theory of multiple forms of negation, an understanding of open domains and the closed world assumption, default reasoning with exceptions, reasoning with respect to time (i.e. a solution to the frame problem, and introspection with regard to previous beliefs), reasoning about actions, introspection, and maintaining multiple views of the world simultaneously.The contribution of this paper is to discuss these developments in a singular, integrated, practical, digestible manner. Some of these ideas exist in a variety of papers spread across decades. They also exist in the minds of a very small community of researchers. Some of these ideas are unpublished. The presentation in this paper is from a different point of view, and intended to be more comprehensive and pedagogical. The presentation is also intended to be accessible to a much wider audience. Both the synthesis and the simplicity of this presentation are absent from the literature.
Microbiological quality of ice creams commercialized in some cities in the state of Rio de Janeiro, Brazil
Authors: DE FARIAS FABRÍCIO F , DA SILVA WALACE R , BOTELHO ANA CAROLINA N , DA HORA IRACEMA M DE C , KRONENBERGER GIOVAN , DA CRUZ ADRIANO G 
Published: October 2006

The microbiological quality of 60 ice cream samples of three commercial brands (A, B and C) of various flavours, commercialized in some towns in the State of Rio de Janeiro, Brazil, was evaluated. Total bacteria count (TCB), coliforms at 35°C (CT), coliforms at 44°C (CF) and presence of Staphylococcus aureus were performed on all samples. TCB ranged from 2.0 × 102to 6.9 × 105 cfu/mL, CT from < 3–≥ 2400 MPN/mL, CF from < 3–1100 MPN/mL and S. aureus from < 10–1.4 × 106 cfu/mL. The level of bacterial contamination found in this study reflects the unhygienic conditions prevalent in manufacturing and storage of ice creams. Actions are thus necessary by the Brazilian regulatory agencies to require the ice cream processing plants to adopt quality guarantee systems, such as good manufacturing practices and hazard analysis and critical control points system.
Putative
cis
-Acting Stem-Loops in the 5′ Untranslated Region of the Severe Acute Respiratory Syndrome Coronavirus Can Substitute for Their Mouse Hepatitis Virus Counterparts
Authors: Kang Hyojeung , Feng Min , Schroeder Megan E. , Giedroc David P. , Leibowitz Julian L. 
Published: October 2006

ABSTRACT
Consensus covariation-based secondary structural models for the 5′ 140 nucleotides of the 5′ untranslated regions (5′UTRs) from mouse hepatitis virus (MHV) and severe acute respiratory syndrome coronavirus (SCoV) were developed and predicted three major helical stem-loop structures, designated stem-loop 1 (SL1), SL2, and SL4. The SCoV 5′UTR was predicted to contain a fourth stem-loop, named SL3, in which the leader transcriptional regulatory sequence (TRS) is folded into a hairpin loop. cDNAs corresponding to MHV/SCoV chimeric genomes were constructed by replacing the complete MHV 5′UTR with the corresponding SCoV sequence and by separately replacing MHV 5′UTR putative SL1, putative SL2, TRS, and putative SL4 with the corresponding SCoV sequences. Chimeric genomes were transcribed in vitro, and viruses were recovered after electroporation into permissive cells. Genomes in which the MHV 5′UTR SL1, SL2, and SL4 were individually replaced by their SCoV counterparts were viable. Chimeras containing the complete SCoV 5′UTR or the predicted SCoV SL3 were not viable. A chimera containing the SCoV 5′UTR in which the SCoV TRS was replaced with the MHV TRS was also not viable. The chimera containing the entire SCoV 5′UTR failed to direct the synthesis of any virus-specific RNA. Replacing the SCoV TRS with the MHV TRS in the MHV/5′UTR SCoV chimera permitted the synthesis of minus-sense genome-sized RNA but did not support the production of positive- or minus-sense subgenomic RNA7. A similar phenotype was obtained with the MHV/SCoV SL3 chimera. These results suggest a role for the TRS in the replication of minus-sense genomic RNA in addition to its known function in subgenomic RNA synthesis.
Macrophage Transcriptional Responses following In Vitro Infection with a Highly Virulent African Swine Fever Virus Isolate
Authors: Zhang Fuquan , Hopwood Paul , Abrams Charles C. , Downing Alison , Murray Frazer , Talbot Richard , Archibald Alan , Lowden Stewart , Dixon Linda K. 
Published: October 2006

ABSTRACTWe used a porcine microarray containing 2,880 cDNAs to investigate the response of macrophages to infection by a virulent African swine fever virus (ASFV) isolate, Malawi LIL20/1. One hundred twenty-five targets were found to be significantly altered at either or both 4 h and 16 h postinfection compared with targets after mock infection. These targets were assigned into three groups according to their temporal expression profiles. Eighty-six targets showed increased expression levels at 4 h postinfection but returned to expression levels similar to those in mock-infected cells at 16 h postinfection. These encoded several proinflammatory cytokines and chemokines, surface proteins, and proteins involved in cell signaling and trafficking pathways. Thirty-four targets showed increased expression levels at 16 h postinfection compared to levels at 4 h postinfection and in mock-infected cells. One host gene showed increased expression levels at both 4 and 16 h postinfection compared to levels in mock-infected cells. The microarray results were validated for 12 selected genes by quantitative real-time PCR. Levels of protein expression and secretion were measured for two proinflammatory cytokines, interleukin 1β and tumor necrosis factor alpha, during a time course of infection with either the virulent Malawi LIL20/1 isolate or the OUR T88/3 nonpathogenic isolate. The results revealed differences between these two ASFV isolates in the amounts of these cytokines secreted from infected cells.
Regulation of Inducible Nitric Oxide Synthase Expression by Viral A238L-Mediated Inhibition of p65/RelA Acetylation and p300 Transactivation
Authors: Granja Aitor G. , Sabina Prado , Salas María L. , Fresno Manuel , Revilla Yolanda 
Published: October 2006

ABSTRACTUncontrolled generation of nitric oxide (NO) by inducible nitric-oxide synthase (iNOS) can cause damage to host cells and inflammation, two undesirable events for virus spreading. African swine fever virus (ASFV) infection regulates iNOS-induced gene expression through the synthesis of the A238L virus protein. We here explored the role of A238L, an NF-κB and NFAT inhibitor, in the regulation of iNOS transcription in macrophages. NO production and iNOS mRNA and protein levels as well as iNOS promoter activity after lipopolysaccharide (LPS)-gamma interferon (IFN-γ) treatment were down-regulated both during ASFV infection and in Raw 264.7 cells stably expressing the viral protein. Overexpression of p300, but not of a histone acetyltransferase (HAT) defective mutant, reverted the A238L-mediated inhibition of both basal and LPS-IFN-γ-induced iNOS promoter activity. Following stimulation with LPS-IFN-γ, p65 and p300 interaction was abolished in Raw-A238L cells. Expression of A238L also inhibited p65/relA and p300 binding to the distal NF-κB sequence of the iNOS promoter together with p65 acetylation. Finally, A238L abrogated p300 transactivation mediated by a GAL4-p300 construction. These results provide evidence for an unique viral mechanism involved in transcriptional regulation of iNOS gene expression.
ORF3 Protein of Hepatitis E Virus Is Not Required for Replication, Virion Assembly, or Infection of Hepatoma Cells In Vitro
Authors: Emerson Suzanne U. , Nguyen Hanh , Torian Udana , Purcell Robert H. 
Published: October 2006

ABSTRACT
A subclone of Huh-7 cells that could be relatively efficiently transfected and infected with hepatitis E virus was identified. Following transfection, infectious virus was produced but remained predominantly cell associated. Intracellular virus, recovered by lysis of transfected cells, infected naïve cells. This in vitro-produced virus appeared to be antigenically identical to virus isolated from clinical samples. Lysates from cells transfected with mutant viral genomes unable to synthesize ORF3 protein contained infectious virions that were similar in number, thermostability, and sedimentation characteristics to those in lysates transfected with wild-type viral genomes. Therefore, in contrast to its requirement in vivo, ORF3 protein is not required for infection of Huh-7 cells or production of infectious virus in vitro.
Rotavirus Anti-VP6 Secretory Immunoglobulin A Contributes to Protection via Intracellular Neutralization but Not via Immune Exclusion
Authors: Corthésy Blaise , Benureau Yann , Perrier Clémentine , Fourgeux Cynthia , Parez Nathalie , Greenberg Harry , Schwartz-Cornil Isabelle 
Published: October 2006

ABSTRACT
Immunoglobulin A (IgA) monoclonal antibodies (MAbs) directed at the conserved inner core protein VP6 of rotavirus, such as the IgA7D9 MAb, provide protective immunity in adult and suckling mice when delivered systemically. While these antibodies do not have traditional in vitro neutralizing activity, they could mediate their antiviral activity either by interfering with the viral replication cycle along the IgA secretory pathway or by acting at mucosal surfaces as secretory IgA and excluding virus from target enterocytes. We sought to determine the critical step at which antirotaviral activity was initiated by the IgA7D9 MAb. The IgA7D9 MAb appeared to directly interact with purified triple-layer viral particles, as shown by immunoprecipitation and immunoblotting. However, protection was not conferred by passively feeding mice with the secretory IgA7D9 MAb. This indicates that the secretory IgA7D9 MAb does not confer protection by supplying immune exclusion activity in vivo. We next evaluated the capacity of polymeric IgA7D9 MAb to neutralize rotavirus intracellularly during transcytosis. We found that when polymeric IgA7D9 MAb was applied to the basolateral pole of polarized Caco-2 intestinal cells, it significantly reduced viral replication and prevented the loss of barrier function induced by apical exposure of the cell monolayer to rotavirus, supporting the conclusion that the antibody carries out its antiviral activity intracellularly. These findings identify a mechanism whereby the well-conserved immunodominant VP6 protein can function as a target for heterotypic antibodies and protective immunity.
Identification of APOBEC3DE as Another Antiretroviral Factor from the Human APOBEC Family
Authors: Dang Ying , Wang Xiaojun , Esselman Walter J. , Zheng Yong-Hui 
Published: October 2006

ABSTRACT
A tandem arrayed gene cluster encoding seven cytidine deaminase genes is present on human chromosome 22. These are APOBEC3A, APOBEC3B, APOBEC3C, APOBEC3DE, APOBEC3F, APOBEC3G, and APOBEC3H. Three of them, APOBEC3G, APOBEC3F, and APOBEC3B, block replication of human immunodeficiency virus type 1 (HIV-1) and many other retroviruses. In addition, APOBEC3A and APOBEC3C block intracellular retrotransposons and simian immunodeficiency virus (SIV), respectively. In opposition to APOBEC genes, HIV-1 and SIV contain a virion infectivity factor (Vif) that targets APOBEC3F and APOBEC3G for polyubiquitylation and proteasomal degradation. Herein, we studied the antiretroviral activities of the human APOBEC3DE and APOBEC3H. We found that only APOBEC3DE had antiretroviral activity for HIV-1 or SIV and that Vif suppressed this antiviral activity. APOBEC3DE was encapsidated and capable of deaminating cytosines to uracils on viral minus-strand DNA, resulting in disruption of the viral life cycle. Other than GG-to-AG and AG-to-AA mutations, it had a novel target site specificity, resulting in introduction of GC-to-AC mutations on viral plus-strand DNA. Such mutations have been detected previously in HIV-1 clinical isolates. In addition, APOBEC3DE was expressed much more extensively than APOBEC3F in various human tissues and it formed heteromultimers with APOBEC3F or APOBEC3G in the cell. From these studies, we concluded that APOBEC3DE is a new contributor to the intracellular defense network, resulting in suppression of retroviral invasion.
Identifying Epitopes Responsible for Neutralizing Antibody and DC-SIGN Binding on the Spike Glycoprotein of the Severe Acute Respiratory Syndrome Coronavirus
Authors: Shih Yi-Ping , Chen Chia-Yen , Liu Shih-Jen , Chen Kuan-Hsuan , Lee Yuan-Ming , Chao Yu-Chan , Chen Yi-Ming Arthur 
Published: October 2006

ABSTRACTThe severe acute respiratory syndrome-associated coronavirus (SARS-CoV) uses dendritic cell-specific ICAM-3 grabbing nonintegrin (DC-SIGN) to facilitate cell entry via cellular receptor-angiotensin-converting enzyme 2. For this project, we used recombinant baculoviruses expressing different lengths of SARS-CoV spike (S) protein in a capture assay to deduce the minimal DC-SIGN binding region. Our results identified the region location between amino acid (aa) residues 324 to 386 of the S protein. We then generated nine monoclonal antibodies (MAbs) against the S protein to map the DC-SIGN-binding domain using capture assays with pseudotyped viruses and observed that MAb SIa5 significantly blocked S protein-DC-SIGN interaction. An enhancement assay using the HKU39849 SARS-CoV strain and human immature dendritic cells confirmed our observation. Data from a pepscan analysis and M13 phage peptide display library system mapped the reactive MAb SIa5 epitope to aa residues 363 to 368 of the S protein. Results from a capture assay testing three pseudotyped viruses with mutated N-linked glycosylation sites of the S protein indicate that only two pseudotyped viruses (N330Q and N357Q, both of which lost glycosylation sites near the SIa5 epitope) had diminished DC-SIGN-binding capacity. We also noted that MAb SIb4 exerted a neutralizing effect against HKU39849; its reactive epitope was mapped to aa residues 435 to 439 of the S protein. We offer the data to facilitate the development of therapeutic agents and preventive vaccines against SARS-CoV infection.
Human Papillomavirus Genotype 31 Does Not Express Detectable MicroRNA Levels during Latent or Productive Virus Replication
Authors: Cai Xuezhong , Li Gu , Laimins Laimonis A. , Cullen Bryan R. 
Published: October 2006

ABSTRACT
It has recently become clear that several pathogenic DNA viruses express virally encoded microRNAs in infected cells. In particular, numerous microRNAs have been identified in a range of human and animal herpesviruses, and individual microRNAs have also been identified in members of the polyoma- and adenovirus families. Although their functions remain largely unknown, it seems likely that these viral microRNAs play an important role in viral replication in vivo. Here we present an analysis of the microRNAs expressed in human cells during the latent and productive phases of the human papillomavirus genotype 31 (HPV31) replication cycle. Although over 500 cellular microRNAs were cloned and identified, not a single HPV31-specific microRNA was obtained. We therefore concluded that HPV31, and possibly human papillomaviruses in general, does not express viral microRNAs.