bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bovine Herpesvirus Tegument Protein VP22 Enhances Thymidine Kinase/Ganciclovir Suicide Gene Therapy for Neuroblastomas Compared to Herpes Simplex Virus VP22
Authors: Qiu Zhaohua , Harms Jerome S. , Zhu Jun , Splitter Gary A. 
Published: March 2004

ABSTRACT
Herpesvirus tegument protein VP22 can enhance the effect of therapeutic proteins in gene therapy, such as thymidine kinase (tk) and p53; however, the mechanism is unclear or controversial. In this study, mammalian expression vectors carrying bovine herpesvirus 1 (BHV-1) VP22 (BVP22) or herpes simplex virus type 1 (HSV-1) VP22 (HVP22) and equine herpesvirus type 4 (EHV-4) tk (Etk) were constructed in order to evaluate and compare the therapeutic potentials of BVP22 and HVP22 to enhance Etk/ganciclovir (Etk/GCV) suicide gene therapy for neuroblastomas by GCV cytotoxicity assays and noninvasive bioluminescent imaging in vitro and in vivo. BVP22 enhanced Etk/GCV cytotoxicity compared to that with HVP22 both in vitro and in vivo. However, assays utilizing a mixture of parental and stably transfected cells indicated that the enhancement was detected only in transfected cells. Thus, the therapeutic potential of BVP22 and HVP22 in Etk/GCV suicide gene therapy in this tumor system is not due to VP22 delivery of Etk into surrounding cells but rather is likely due to an enhanced intracellular effect.
Detection of Template Strand Switching during Initiation and Termination of DNA Replication of Porcine Circovirus
Authors: Cheung Andrew K. 
Published: March 2004

ABSTRACT
Nucleotide substitution mutagenesis was conducted to investigate the importance of the inverted repeats (palindrome) at the origin of DNA replication (Ori) of porcine circovirus type 1 (PCV1). Viral genomes with engineered mutations on either arm or both arms of the palindrome were not impaired in protein synthesis and yielded infectious progeny viruses with restored or new palindromes. Thus, a flanking palindrome at the Ori was not essential for initiation of DNA replication, but one was generated inevitably at termination. Among the 26 viruses recovered, 16 showed evidence of template strand switching, from minus-strand genome DNA to palindromic strand DNA, during biosynthesis of the Ori. Here I propose a novel rolling-circle “melting-pot” model for PCV1 DNA replication. In this model, the replicator Rep protein complex binds, destabilizes, and nicks the Ori sequence to initiate leading-strand DNA synthesis. All four strands of the destabilized inverted repeats exist in a “melted” configuration, and the minus-strand viral genome and a palindromic strand are available as templates, simultaneously, during initiation or termination of DNA replication. Inherent in this model is a “gene correction” or “terminal repeat correction” mechanism that can restore mutilated inverted-repeat sequences to a palindrome at the Ori of circular DNAs or at the termini of circularized linear DNAs. Potentially, the melted state of the inverted repeats increases the rate of noncomplementary or illegitimate nucleotide incorporation into the palindrome. Thus, this melting-pot model provides insight into the mechanisms of DNA replication, gene correction, and illegitimate recombination at the Ori of PCV1, and it may be applicable to the replication of other circular DNA molecules.
The Ribonucleotide Reductase R1 Homolog of Murine Cytomegalovirus Is Not a Functional Enzyme Subunit but Is Required for Pathogenesis
Authors: Lembo David , Donalisio Manuela , Hofer Anders , Cornaglia Maura , Brune Wolfram , Koszinowski Ulrich , Thelander Lars , Landolfo Santo 
Published: March 2004

ABSTRACT
Ribonucleotide reductase (RNR) is the key enzyme in the biosynthesis of deoxyribonucleotides. Alpha- and gammaherpesviruses express a functional enzyme, since they code for both the R1 and the R2 subunits. By contrast, betaherpesviruses contain an open reading frame (ORF) with homology to R1, but an ORF for R2 is absent, suggesting that they do not express a functional RNR. The M45 protein of murine cytomegalovirus (MCMV) exhibits the sequence features of a class Ia RNR R1 subunit but lacks certain amino acid residues believed to be critical for enzymatic function. It starts to be expressed independently upon the onset of viral DNA synthesis at 12 h after infection and accumulates at later times in the cytoplasm of the infected cells. Moreover, it is associated with the virion particle. To investigate direct involvement of the virally encoded R1 subunit in ribonucleotide reduction, recombinant M45 was tested in enzyme activity assays together with cellular R1 and R2. The results indicate that M45 neither is a functional equivalent of an R1 subunit nor affects the activity or the allosteric control of the mouse enzyme. To replicate in quiescent cells, MCMV induces the expression and activity of the cellular RNR. Mutant viruses in which the M45 gene has been inactivated are avirulent in immunodeficient SCID mice and fail to replicate in their target organs. These results suggest that M45 has evolved a new function that is indispensable for virus replication and pathogenesis in vivo.
African Swine Fever Virus Structural Protein p54 Is Essential for the Recruitment of Envelope Precursors to Assembly Sites
Authors: Rodríguez Javier M. , García-Escudero Ramón , Salas María L. , Andrés Germán 
Published: March 2004

ABSTRACT

The assembly of African swine fever virus (ASFV) at the cytoplasmic virus factories commences with the formation of precursor membranous structures, which are thought to be collapsed cisternal domains recruited from the surrounding endoplasmic reticulum (ER). This report analyzes the role in virus morphogenesis of the structural protein p54, a 25-kDa polypeptide encoded by the
E183L
gene that contains a putative transmembrane domain and localizes at the ER-derived envelope precursors. We show that protein p54 behaves in vitro and in infected cells as a type I membrane-anchored protein that forms disulfide-linked homodimers through its unique luminal cysteine. Moreover, p54 is targeted to the ER membranes when it is transiently expressed in transfected cells. Using a lethal conditional recombinant, vE183Li, we also demonstrate that the repression of p54 synthesis arrests virus morphogenesis at a very early stage, even prior to the formation of the precursor membranes. Under restrictive conditions, the virus factories appeared as discrete electron-lucent areas essentially free of viral structures. In contrast, outside the assembly sites, large amounts of aberrant zipper-like structures formed by the unprocessed core polyproteins pp220 and pp62 were produced in close association to ER cisternae. Altogether, these results indicate that the transmembrane structural protein p54 is critical for the recruitment and transformation of the ER membranes into the precursors of the viral envelope.
Rapid Diagnosis of Ebola Hemorrhagic Fever by Reverse Transcription-PCR in an Outbreak Setting and Assessment of Patient Viral Load as a Predictor of Outcome
Authors: Towner Jonathan S. , Rollin Pierre E. , Bausch Daniel G. , Sanchez Anthony , Crary Sharon M. , Vincent Martin , Lee William F. , Spiropoulou Christina F. , Ksiazek Thomas G. , Lukwiya Mathew , Kaducu Felix , Downing Robert , Nichol Stuart T. 
Published: March 2004

ABSTRACT

The largest outbreak on record of Ebola hemorrhagic fever (EHF) occurred in Uganda from August 2000 to January 2001. The outbreak was centered in the Gulu district of northern Uganda, with secondary transmission to other districts. After the initial diagnosis of Sudan ebolavirus by the National Institute for Virology in Johannesburg, South Africa, a temporary diagnostic laboratory was established within the Gulu district at St. Mary's Lacor Hospital. The laboratory used antigen capture and reverse transcription-PCR (RT-PCR) to diagnose Sudan ebolavirus infection in suspect patients. The RT-PCR and antigen-capture diagnostic assays proved very effective for detecting ebolavirus in patient serum, plasma, and whole blood. In samples collected very early in the course of infection, the RT-PCR assay could detect ebolavirus 24 to 48 h prior to detection by antigen capture. More than 1,000 blood samples were collected, with multiple samples obtained from many patients throughout the course of infection. Real-time quantitative RT-PCR was used to determine the viral load in multiple samples from patients with fatal and nonfatal cases, and these data were correlated with the disease outcome. RNA copy levels in patients who died averaged 2 log
10
higher than those in patients who survived. Using clinical material from multiple EHF patients, we sequenced the variable region of the glycoprotein. This Sudan ebolavirus strain was not derived from either the earlier Boniface (1976) or Maleo (1979) strain, but it shares a common ancestor with both. Furthermore, both sequence and epidemiologic data are consistent with the outbreak having originated from a single introduction into the human population.
Suppression of the Induction of Alpha, Beta, and Gamma Interferons by the NS1 and NS2 Proteins of Human Respiratory Syncytial Virus in Human Epithelial Cells and Macrophages
Authors: Spann Kirsten M. , Tran Kim-C. , Chi Bo , Rabin Ronald L. , Collins Peter L. 
Published: March 2004

ABSTRACT
Wild-type human respiratory syncytial virus (HRSV) is a poor inducer of alpha/beta interferons (IFN-α/β). However, recombinant HRSV lacking the NS1 and NS2 genes (ΔNS1/2) induced high levels of IFN-α and -β in human pulmonary epithelial cells (A549) as well as in macrophages derived from primary human peripheral blood monocytes. Results with NS1 and NS2 single- and double-gene-deletion viruses indicated that the two proteins function independently as well as coordinately to achieve the full inhibitory effect, with NS1 having a greater independent role. The relative contributions of the individual NS proteins were the converse of that recently described for bovine RSV (J. F. Valarcher, J. Furze, S. Wyld, R. Cook, K. K. Conzelmann, and G. Taylor, J. Virol. 77:8426-8439, 2003). This pattern of inhibition by HRSV NS1 and NS2 also extended to the newly described antiviral cytokines IFN-λ1, -2 and -3.
Genomically Intact Endogenous Feline Leukemia Viruses of Recent Origin
Authors: Roca Alfred L. , Pecon-Slattery Jill , O'Brien Stephen J. 
Published: March 2004

ABSTRACTWe isolated and sequenced two complete endogenous feline leukemia viruses (enFeLVs), designated enFeLV-AGTT and enFeLV-GGAG. In enFeLV-AGTT, the open reading frames are reminiscent of a functioning FeLV genome, and the 5′ and 3′ long terminal repeat sequences are identical. Neither endogenous provirus is genetically fixed in cats but polymorphic, with 8.9 and 15.2% prevalence for enFeLV-AGTT and enFeLV-GGAG, respectively, among a survey of domestic cats. Neither provirus was found in the genomes of related species of theFelisgenus, previously shown to harbor enFeLVs. The absence of mutational divergence, polymorphic incidence in cats, and absence in related species suggest that these enFeLVs may have entered the germ line more recently than previously believed, perhaps coincident with domestication, and reopens the question of whether some enFeLVs might be replication competent.
The Dutch CISOE-A framework for cytology reporting increases efficacy of screening upon standardisation since 1996
Authors: Bulk S , van Kemenade F J , Rozendaal L , Meijer C J L M 
Published: March 2004

Aim:To describe the effect of introducing the CISOE-A framework for reporting cervical cytology results, including changes in repeat and referral advice in the Netherlands, on the efficacy of the screening programme. Changes in the distribution of cytological results, the detection rate of cervical intraepithelial neoplasia (CIN) lesions, and the detection rate of squamous cervical carcinoma are reported.Methods:The results of all gynaecology cytological and histological examinations, as registered in the nationwide database for histopathology and cytopathology (PALGA) from 1990 to 2000, were retrieved from seven laboratories in the greater Amsterdam area.Results:After the introduction of the CISOE-A classification, cytological results with equivocal diagnoses decreased significantly from 11.3% to 2.6%, without an increase in the percentages of moderate dyskaryosis or worse. During the study period, the detection rate of histologically diagnosed high grade CIN lesions increased significantly from 4.1 to 6.4/1000 smears, whereas there was no change in the detection rates of low grade lesions or invasive cervical cancer.Conclusions:The introduction of the new CISOE-A classification system resulted in a substantial decrease of equivocal results and repeat recommendations, without a decrease in the detection rate of high grade lesions, making the screening programme more efficacious.
Distribution of constitutive (COX-1) and inducible (COX-2) cyclooxygenase in postviral human liver cirrhosis: a possible role for COX-2 in the pathogenesis of liver cirrhosis
Authors: Mohammed N A , El-Aleem S A , El-Hafiz H A , McMahon R F T 
Published: March 2004

Aims:Prostaglandins produced by the action of cyclooxygenases (COX) are important mediators of systemic vasodilatation and inflammation in liver cirrhosis. The aim of this study was to investigate the distribution of COX-1 and COX–2 in postviral cirrhosis.Methods:The immunohistochemical expression of the constitutive (COX-1) and the inducible (COX-2) isoenzymes was investigated in 15 patients with cirrhosis after hepatitis B and C infection; three normal control livers were also analysed.Results:COX-2 was absent from normal liver but was highly expressed in cirrhosis, mainly in the inflammatory, sinusoidal, vascular endothelial, and biliary epithelial cells. Low amounts of COX-1 were expressed in both normal and cirrhotic livers, exclusively in sinusoidal and vascular endothelial cells, with no differences seen between normal and cirrhotic livers.Conclusions:COX-2 is overexpressed in liver cirrhosis, and possibly contributes to prostaglandin overproduction, which may be a major component of the inflammation and hyperdynamic circulation associated with cirrhosis. Because COX-2 is thought to contribute to tumour development, high COX-2 production could be a contributor to hepatocellular carcinoma development in cirrhosis. The finding of COX-2 and not COX-1 upregulation in cirrhosis could provide a possible new role for selective COX-2 inhibitors in reducing inflammation and minimising the occurrence of hepatocellular carcinoma in patients with cirrhosis.
Analytical and diagnostic accuracy of “second generation” assays for thyrotrophin receptor antibodies with radioactive and chemiluminescent tracers
Authors: Villalta D , Orunesu E , Tozzoli R , Montagna P , Pesce G , Bizzaro N , Bagnasco M 
Published: March 2004

Aims:To investigate the analytical and diagnostic accuracy of thyrotrophin (TSH) receptor antibody assays using recombinant human TSH receptors.Methods:Sera from 68 patients with Graves’ disease, 23 patients with autoimmune thyroiditis, and 119 healthy controls were evaluated in four different laboratories using both radioactive and chemiluminescent tracers. Functional sensitivity, interlaboratory precision, optimal cutoff values for Graves’ disease, and the correlation between the two methods were evaluated.Results:Functional sensitivity was 0.98 IU/litre for both assays. Interlaboratory precision, expressed as per cent coefficient of variation over a wide range of antibody concentrations, varied from 5.7% to 15.1% for the radioligand, and from 6.6% to 19.9% for the chemiluminescence assay. The two methods (radioactive and chemiluminescent) were closely correlated. All the sera from untreated or relapsing patients with Graves’ disease gave TSH receptor antibody values above 2.1 IU/litre, whereas in none of the healthy controls did values exceed 2.5 IU/litre. Receiver operating curve analysis allowed an optimal cutoff point to be defined at 1.99 IU/litre, according to a sensitivity of 100% and specificity of 99.1%.Conclusions:These data show the high analytical and diagnostic accuracy of the human TSH receptor assays, both with radioactive and chemiluminescent tracers, when both functional sensitivity and interlaboratory reproducibility are considered. These two methods could be proposed as first line diagnostic markers for Graves’ disease.
Expression of connective tissue growth factor (CCN2) in desmoplastic small round cell tumour
Authors: Rachfal A W , Luquette M H , Brigstock D R 
Published: March 2004

Background:Desmoplastic small round cell tumour (DSRCT) is a rare and often fatal abdominal tumour that is distinguished by well defined islands of cells, surrounded by prominent desmoplastic stroma. As in certain other tumours, the function of the Wilms’s tumour protein (WT1) in repressing gene transcription is lost in DSRCT.Aims:To assess the expression and localisation of connective tissue growth factor (CCN2) in DSRCT because this protein is transcriptionally repressed by WT1 and is associated with the production of abundant extracellular matrix.Methods:CCN2 was assessed by in situ hybridisation and immunohistochemistry.Results:CCN2 mRNA and protein were colocalised to the tumour cells themselves, in addition to stromal fibroblasts and vascular endothelial cells.Conclusions:These data show that CCN2 is produced in high amounts by several cell types in DSRCT, and highlight a potential role for this factor in the autocrine and paracrine regulation of tumour cell growth, matrigenesis, and angiogenesis.
Does activity in research correlate with visibility?: Figure 1
Authors: Reynolds T M , Wierzbicki A S 
Published: March 2004

Background:A previous survey has highlighted the fact that most individuals in chemical pathology identifiable from specialist society membership failed to publish material in Medline cited journals during a five year period. It could be considered that published research that is not cited in other work is not useful unless it has achieved visibility, as demonstrated by citation in another research publication.Aims:To determine whether the frequency of research publication is associated with research visibility.Methods:A random selection from the previous survey was investigated to determine whether the frequency of research publication is associated with research visibility.Results:There was a logarithmic relation between the frequency of publication and visibility, with an increasing probability of citation as publication frequency increases.Conclusions:If academic activity is to survive then individuals must stay active in research; this requires a continuing commitment to a tradition of support for individuals at all stages of their careers engaging in research.
BIFURCATIONS OF VORONOI DIAGRAMS AND ITS APPLICATION TO BRAID THEORY
Authors: SAJI KENTARO 
Published: March 2004

We study bifurcations of Voronoi diagrams on the plane. The generic bifurcations of Voronoi diagrams for moving points are classified into four types. A braid has an associated family of Voronoi diagrams. If we admit only three types among four in the associated generic family of Voronoi diagrams, the braid type reduces to a braid with k half twists for some integer k.
Social Marketing: Are We Fiddling While Rome Burns? A Response to Andreasen and Wells
Authors: Goldberg Marvin E. 
Published: March 2004

Andreasen's (this issue) and Wells’ (this issue) comments regarding my initial article (Goldberg, 1995) are both reasoned and thought provoking. Both endorse the need for marketers to consider applying their skills to issues that are problematic in our society today. The devil is in the details!First let me address Andreasen's comments. One of his primary concerns appears to be a cautionary note for young marketing scholars: Beware the temptation to address a social ill as the primary motivation for developing research. He argues that academics, and especially untenured academics, ought to be driven to explore “fundamental theoretical problems.” At the same time he suggests that there is ample opportunity to “advance fundamental knowledge while at the same time doing good” (Andreasen, this issue). Petty and Cacioppo (1996) made the same case, concluding with a plea to basic researchers to make their research more accessible to applied researchers and to the latter to become more sensitive to the potential of theory‐driven research. Unfortunately, this is unlikely to be the last time we hear this plea, unless some meaningful way of operationalizing it captures the imagination of at least a subset of consumer researchers.
Introduction to the Special Issue on Ethical Trade‐Offs in Consumer Decision Making
Authors: Irwin Julie R. 
Published: March 2004

How selfish soever man may be supposed, there are evidently some principles in his nature, which interest him in the fortune of others, and render their happiness necessary to him, though he derives nothing from it except the pleasure of seeing it.Adam Smith, The Theory of Moral Sentiments, 1759, p. 1
Administration of low-dose LH induces ovulation and prevents vascular hyperpermeability and vascular endothelial growth factor expression in superovulated rats
Authors: Gómez R , Lima I , Simón C , Pellicer A 
Published: March 2004

The administration, to rats, of a combination of pregnant mares serum gonadotrophin (PMSG) and human chorionic gonadotrophin (hCG) in high doses induces the ovarian hyperstimulation syndrome (OHSS) which is characterized by increased vascular permeability (VP) and simultaneous overexpression of vascular endothelial growth factor (VEGF) in ovarian cells. hCG has a longer half-life than LH and a greater biological activity, expressed in a higher incidence of complications such as OHSS. Similarly, FSH may also be related to the ovulatory changes within the follicle as there is a simultaneous surge in spontaneous cycles. The aim of this study was to compare the capacity of hCG, FSH and LH to induce ovulation and simultaneously prevent OHSS in the animal model. Immature female rats were treated with 10 IU PMSG for 4 days, and ovulation was triggered with saline, 10 IU hCG, 10 IU FSH, 10 IU LH or 60 IU LH. The number of oocytes ovulated into the tubes, VP and mRNA VEGF expression were evaluated and compared.
All the hormones employed were as effective at triggering ovulation, with similar significant P values when compared with the control for which saline was used. The use of 10 IU LH resulted in significantly lower VP and VEGF expression than that seen in the groups treated with 10 IU hCG, 10 IU FSH or 60 IU LH. In conclusion, FSH and hCG, as well as a sixfold increase in LH, displayed similar biological activities, including increased VP due to excessive VEGF expression. The use of lower doses of LH produced similar rates of ovulation, while preventing the undesired changes in permeability. These experiments should therefore encourage clinicians to determine the optimal dose of LH to be employed in women in order to trigger ovulation and, at the same time, avoid the risk of OHSS.
Contrasts, independent component analysis, and blind deconvolution
Authors: Comon P. 
Published: March 2004

AbstractA general definition of contrast criteria is proposed, which induces the concept of trivial filters. These optimization criteria enjoy identifiability properties, and aim at delivering outputs satisfying specific properties, such as statistical independence or a discrete character. Several ways of building new contrast criteria are described. It is then briefly elaborated on practical numerical algorithms. Copyright © 2004 John Wiley & Sons, Ltd.