bluuebunny/crossref_metadata_2025_split huggingface dataset:
Identification of Alpha-Hemolytic Streptococci by Pyrosequencing the 16S rRNA Gene and by Use of VITEK 2
Authors: Haanperä Marjo , Jalava Jari , Huovinen Pentti , Meurman Olli , Rantakokko-Jalava Kaisu 
Published: January 2007

ABSTRACTAlpha-hemolytic streptococci are very difficult to identify by phenotypic methods. In this study, a pyrosequencing method for the identification of streptococcal species based on two variable regions of the 16S rRNA gene is described. Almost all studied streptococcal species (n= 51) represented by their type strains could be differentiated except for some closely related species of theStreptococcus bovisorS. salivariusgroup. The pyrosequencing results of alpha-hemolytic streptococci isolated from blood (n= 99) or from the normal pharyngeal microbiota (n= 25) were compared to the results obtained by the VITEK 2 with GP card (bioMérieux, Marcy l'Etoile, France). As expected, the results of the two methods did not completely agree, but 93 (75.0%) of the isolates assigned to the same streptococcal group by both methods and 57 (46.0%) reached consistent results at the species level. However, 10 strains remained unidentified by VITEK 2, and 4 isolates could not be assigned to any streptococcal group by pyrosequencing. Identification of members of theS. mitisandS. sanguinisgroups proved difficult for both methods. Furthermore, the pyrosequencing analysis revealed great sequence variation, since only 43 (32.3%) of the 133 isolates analyzed by pyrosequencing had sequences identical to a type strain. The variation was greatest in the pharyngeal isolates, slightly lower in the blood culture isolates, and nonexistent in invasive pneumococcal isolates (n= 17) that all had theS. pneumoniaetype strain sequence. The resolution of the results obtained by the two methods is impeded by the lack of a proper gold standard.
The MyD116 African Swine Fever Virus Homologue Interacts with the Catalytic Subunit of Protein Phosphatase 1 and Activates Its Phosphatase Activity
Authors: Rivera José , Abrams Charles , Hernáez Bruno , Alcázar Alberto , Escribano José M. , Dixon Linda , Alonso Covadonga 
Published: January 2007

ABSTRACT

The DP71L protein of African swine fever virus (ASFV) shares sequence similarity with the herpes simplex virus ICP34.5 protein over a C-terminal domain. We showed that the catalytic subunit of protein phosphatase 1 (PP1) interacts specifically with the ASFV DP71L protein in a yeast two-hybrid screen. The chimeric full-length DP71L protein, from ASFV strain Badajoz 71 (BA71V), fused to glutathione
S
-transferase (DP71L-GST) was expressed in
Escherichia coli
and shown to bind specifically to the PP1-α catalytic subunit expressed as a histidine fusion protein (6×His-PP1α) in
E. coli
. The functional effects of this interaction were investigated by measuring the levels of PP1 and PP2A in ASFV-infected Vero cells. This showed that infection with wild-type ASFV strain BA71V activated PP1 between two- and threefold over that of mock-infected cells. This activation did not occur in cells infected with the BA71V isolate in which the DP71L gene had been deleted, suggesting that expression of DP71L leads to PP1 activation. In contrast, no effect was observed on the activity of PP2A following ASFV infection. We showed that infection of cells with wild-type BA71V virus resulted in decreased phosphorylation of the α subunit of eukaryotic initiation factor 2 (eIF-2α). ICP34.5 recruits PP1 to dephosphorylate the α subunit of eukaryotic translational initiation factor 2 (also known as eIF-2α); possibly the ASFV DP71L protein has a similar function.
In Vitro Study of the Effects of Precore and Lamivudine-Resistant Mutations on Hepatitis B Virus Replication
Authors: Heipertz Richard A. , Miller Thomas G. , Kelley Colleen M. , Delaney William E. , Locarnini Stephen A. , Isom Harriet C. 
Published: January 2007

ABSTRACTUnderstanding the consequences of mutation in the hepatitis B virus (HBV) genome on HBV replication is critical for treating chronic HBV infection. In this study, HBV replication in HepG2 cells initiated by transduction with precore (PC), rtM204I, and wild-type (wt) HBV recombinant baculoviruses was compared. The pattern and magnitude of HBV replication initiated by the PC HBV recombinant baculovirus were similar to those observed for wt HBV throughout the time course examined. In contrast, when the rtM204I mutation was introduced into wt HBV, by day 10 postinfection the levels of intra- and extracellular HBV DNA were markedly reduced compared to those for wt HBV. Although the rtM204I mutation reduced the production of HBV replicative intermediates, no effect on the level of covalently closed circular DNA or HBV transcripts was observed at late time points. Coinfection studies with different ratios of wt and rtM204I baculoviruses showed that the rtM204I variant did not produce a product that inhibited HBV replication. However, the combination of the wt and rtM204I baculoviruses yielded HBV DNA levels at late time points that were greater than those for the wt alone, suggesting that wt polymerase may function intransto boost rtM204I replication. We concluded that the rtM204I mutation generates a polymerase that is not only resistant to lamivudine but also replicates nucleic acids to lower levels in vitro.
p53-Independent Endoplasmic Reticulum Stress-Mediated Cytotoxicity of a Newcastle Disease Virus Strain in Tumor Cell Lines
Authors: Fábián Zsolt , Csatary Christine M. , Szeberényi József , Csatary Laszlo K. 
Published: January 2007

ABSTRACT
While Newcastle disease virus (NDV) causes serious infections in birds, it is apparently nonpathogenic in mammalian species, including humans. Previous observations and small-scale clinical trials indicated that NDV exerts oncolytic effects. Isolates of NDV were found to have selective affinity to transformed cells. We previously showed that the attenuated NDV strain MTH-68/H causes apoptotic cell death in cultures of PC12 rat pheochromocytoma cells. The aim of the present study was to extend MTH-68/H cytotoxicity testing with human tumor cell lines and to analyze certain biochemical aspects of its oncolytic effect. MTH-68/H was found to be able to kill a wide range of transformed cells by apoptosis. While caspase-8 and caspase-9 are not involved in MTH-68/H-induced apoptosis, activation of caspase-3 and caspase-12 was detected in virus-infected PC12 cells. A human glioblastoma cell line with repressible expression of the p53 protein did not show any difference in MTH-68/H sensitivity in its p53-expressing and p53-depleted states, indicating that the apoptotic process induced by MTH-68/H does not depend on p53. Apoptosis was accompanied by virus replication in two tumor cell lines tested (PC12 cells and HeLa human cervical cells), and signs of endoplasmic reticulum stress (phosphorylation of protein kinase R-like endoplasmic reticulum kinase and eIF2α) were also detected in transformed cells. In contrast, proliferation of nontransformed mouse and rat fibroblast cell lines and human primary fibroblasts was not affected by MTH-68/H treatment. MTH-68/H thus selectively kills tumor cell cultures by inducing endoplasmic reticulum stress leading to p53-independent apoptotic cell death.
Characterization of the vasorelaxation to methanandamide in rat gastric arteries
Authors: Breyne Joke , Van de Voorde Johan , Vanheel Bert 
Published: January 2007

In the present study, the relaxant effect of the cannabinoid methanandamide was explored in rat gastric arteries. Since in some vessels cannabinoids have been shown to release calcitonin gene-related peptide (CGRP) from perivascular nerves, the influence of methanandamide was compared with that of exogenous CGRP. Methanandamide and CGRP elicited concentration-dependent, endothelium-independent relaxations. Methanandamide-induced relaxations were unaffected by the CB1receptor antagonist AM251, the CB2receptor antagonists AM630 and SR144528, and combined pre-exposure to AM251 and SR144528. Pre-exposure to O-1918, an antagonist of a novel nonCB1/nonCB2cannabinoid receptor, did not influence the relaxations to methanandamide. Capsaicin or capsazepine treatment slightly inhibited methanandamide-induced relaxations. Preincubation with 30 mmol/L extracellular K+or 3 mmol/L TEA had no significant effect on the responses elicited by methanandamide, but reduced CGRP-induced relaxations. Relaxation to 10−5mol/L methanandamide was significantly blunted by Bay K8644 and by preincubation with nifedipine. Furthermore, 10−5mol/L methanandamide significantly inhibited CaCl2-induced contractions in norepinephrine-stimulated vessels previously depleted of intra- and extracellular Ca2+. Finally, preincubation with 10−5mol/L methanandamide almost completely abolished high K+-induced contractions. These findings suggest that the vasorelaxant action of methanandamide in rat gastric arteries is not mediated by stimulation of known cannabinoid receptors and only partly related to stimulation of TRPV1receptors on perivascular nerves. At high concentrations, methanandamide might induce relaxation by reducing calcium entry into the smooth muscle cells.
4-D GEOMETRICAL MODELING OF MATERIAL AGING
Authors: CHUDNOVSKY ALEXANDER , PRESTON SERGE 
Published: January 2007

The 4-dim intrinsic (material) Riemannian metric G of the material 4-D space-time continuum P is utilized as the characteristic of the aging processes developing in the material. Manifested through variation of basic material characteristics such as density, moduli of elasticity, yield stress, strength, and toughness., the aging process is modeled as the evolution of the metric G (most importantly of its time component G00) of the material space-time P embedded into 4-D Newtonian space-time with a Euclidean metric. The evolutional equation for the metric G is derived by the classical variational approach. Construction of the Lagrangian for an aging elastic medium and the derivation of a system of coupled elastostatic and aging equations constitute the central part of the work. The external and internal balance laws associated with symmetries of material and physical space-time geometries are briefly reviewed from a new viewpoint.
Establishment of Human Colon Cancer Cell Lines from Fresh Tumors versus Xenografts: Comparison of Success Rate and Cell Line Features
Authors: Dangles-Marie Virginie , Pocard Marc , Richon Sophie , Weiswald Louis-Bastien , Assayag Franck , Saulnier Patrick , Judde Jean-Gabriel , Janneau Jean-Louis , Auger Nathalie , Validire Pierre , Dutrillaux Bernard , Praz Françoise , Bellet Dominique , Poupon Marie-France 
Published: January 2007

Abstract
Obtaining representative human colon cancer cell lines from fresh tumors is technically difficult. Using 32 tumor fragments from patients with colon cancer, the present study shows that prior xenograft leads to more efficient cell line establishment compared with direct establishment from fresh tumors (P &lt; 0.05). From 26 tumor specimens, we successfully established 20 tumor xenografts in nude mice (77%); among 19 of these xenografts, 9 (47%) led to cell lines, including four from liver metastases. Only 3 of 31 tumor specimens (9.7%) grew immediately in vitro, and all were derived from primary tumors. To compare major phenotypic and genotypic characteristics of human colon cancer cell lines derived from the same tumor fragment using two protocols, the two pairs of cell lines obtained from 2 of 32 tumor fragments were extensively studied. They displayed similar morphology and were able to form compact spheroids. Chemosensitivity to 5-fluorouracil, CPT11, and L-OHP differed between cell lines obtained from patient tumors and those derived from xenografts. Matched cell lines shared a common core of karyotype alterations and distinctive additional chromosomal aberrations. Expression levels of genes selected for their role in oncogenesis evaluated by real-time quantitative PCR were found to be statistically correlated whatever the in vitro culture model used. In conclusion, xenotransplantation in mice of tumor fragments before establishment of cell lines enables generation of more novel human cancer cell lines for investigation of colon cancer cell biology, opening up the opportunity of reproducing the diversity of this disease. [Cancer Res 2007;67(1):398–407]
Credentialing Preclinical Pediatric Xenograft Models Using Gene Expression and Tissue Microarray Analysis
Authors: Whiteford Craig C. , Bilke Sven , Greer Braden T. , Chen Qingrong , Braunschweig Till A. , Cenacchi Nicola , Wei Jun S. , Smith Malcolm A. , Houghton Peter , Morton Christopher , Reynolds C. Patrick , Lock Richard , Gorlick Richard , Khanna Chand , Thiele Carol J. , Takikita Mikiko , Catchpoole Daniel , Hewitt Stephen M. , Khan Javed 
Published: January 2007

AbstractHuman tumor xenografts have been used extensively for rapid screening of the efficacy of anticancer drugs for the past 35 years. The selection of appropriate xenograft models for drug testing has been largely empirical and has not incorporated a similarity to the tumor type of origin at the molecular level. This study is the first comprehensive analysis of the transcriptome of a large set of pediatric xenografts, which are currently used for preclinical drug testing. Suitable models representing the tumor type of origin were identified. It was found that the characteristic expression patterns of the primary tumors were maintained in the corresponding xenografts for the majority of samples. Because a prerequisite for developing rationally designed drugs is that the target is expressed at the protein level, we developed tissue arrays from these xenografts and corroborated that high mRNA levels yielded high protein levels for two tested genes. The web database and availability of tissue arrays will allow for the rapid confirmation of the expression of potential targets at both the mRNA and the protein level for molecularly targeted agents. The database will facilitate the identification of tumor markers predictive of response to tested agents as well as the discovery of new molecular targets. [Cancer Res 2007;67(1):32–40]
RET/Papillary Thyroid Carcinoma Oncogenic Signaling through the Rap1 Small GTPase
Authors: De Falco Valentina , Castellone Maria Domenica , De Vita Gabriella , Cirafici Anna Maria , Hershman Jerome M. , Guerrero Carmen , Fusco Alfredo , Melillo Rosa Marina , Santoro Massimo 
Published: January 2007

Abstract
RET/papillary thyroid carcinoma (PTC) oncoproteins result from the in-frame fusion of the RET receptor tyrosine kinase with protein dimerization motifs encoded by heterologous genes. Here, we show that RET/PTC1 activates the Rap1 small GTPase. The activation of Rap1 was dependent on the phosphorylation of RET Tyr1062. RET/PTC1 recruited a complex containing growth factor receptor binding protein 2–associated binding protein 1 (Gab1), CrkII (v-crk sarcoma virus CT10 oncogene homologue II), and C3G (Rap guanine nucleotide exchange factor 1). By using dominant-negative and small interfering duplex (small interfering RNA) oligonucleotides, we show that RET/PTC1–mediated Rap1 activation was dependent on CrkII, C3G, and Gab1. Activation of Rap1 was involved in the RET/PTC1–mediated stimulation of the BRAF kinase and the p42/p44 mitogen-activated protein kinases. Proliferation and stress fiber formation of RET/PTC1–expressing PC Cl 3 thyroid follicular cells were inhibited by the dominant-negative Rap1(N17) and by Rap1–specific GTPase-activating protein. Thus, Rap1 is a downstream effector of RET/PTC and may contribute to the transformed phenotype of RET/PTC–expressing thyrocytes. [Cancer Res 2007;67(1):381–90]
Delivery of CCL21 to Metastatic Disease Improves the Efficacy of Adoptive T-Cell Therapy
Authors: Thanarajasingam Uma , Sanz Laura , Diaz Rosa , Qiao Jian , Sanchez-Perez Luis , Kottke Tim , Thompson Jill , Chester John , Vile Richard G. 
Published: January 2007

AbstractAdoptive T-cell transfer has achieved significant clinical success in advanced melanoma. However, therapeutic efficacy is limited by poor T-cell survival after adoptive transfer and by inefficient trafficking to tumor sites. Here, we report that intratumoral expression of the chemokine CCL21 enhances the efficacy of adoptive T-cell therapy in a mouse model of melanoma. Based on our novel observation that CCL21 is highly chemotactic for activated OT-1 T cells in vitro and down-regulates expression of CD62L, we hypothesized that tumor cell–mediated expression of this chemokine might recruit, and retain, adoptively transferred T cells to the sites of tumor growth. Mice bearing metastatic tumors stably transduced with CCL21 survived significantly longer following adoptive T-cell transfer than mice bearing non–CCL21-expressing tumors. However, although we could not detect increased trafficking of the adoptively transferred T cells to tumors, tumor-expressed CCL21 promoted the survival and cytotoxic activity of the adoptively transferred T cells and led to the priming of antitumor immunity following T-cell transfer. To translate these observations into a protocol of real clinical usefulness, we showed that adsorption of a retrovirus encoding CCL21 to OT-1 T cells before adoptive transfer increased the therapeutic efficacy of a subsequently administered dose of OT-1 T cells, resulting in cure of metastatic disease and the generation of immunologic memory in the majority of treated mice. These studies indicate a promising role for CCL21 in enhancing the therapeutic efficacy of adoptive T-cell therapy. [Cancer Res 2007;67(1):300–8]
An Osteoprotegerin-like Peptidomimetic Inhibits Osteoclastic Bone Resorption and Osteolytic Bone Disease in Myeloma
Authors: Heath Deborah J. , Vanderkerken Karin , Cheng Xin , Gallagher Orla , Prideaux Matthew , Murali Ramachandran , Croucher Peter I. 
Published: January 2007

AbstractMultiple myeloma is a B-cell malignancy characterized by the uncontrolled growth of plasma cells in the bone marrow and the development of osteolytic bone disease. Myeloma cells express the receptor activator of nuclear factor κB ligand (RANKL), induce RANKL expression in the bone marrow, and down-regulate expression of the decoy receptor osteoprotegerin, thereby promoting bone resorption. Targeting this system in myeloma has clear therapeutic potential. However, osteoprotegerin also binds tumor necrosis factor–related apoptosis inducing ligand (TRAIL) and prevents TRAIL-induced apoptosis of myeloma cells. Whether or not osteoprotegerin can bind TRAIL and prevent apoptosis in vivo and the relative importance of osteoprotegerin binding to TRAIL and RANKL are unclear. In the present study, we have investigated the ability of an osteoprotegerin-like peptidomimetic (OP3-4), designed to block the RANKL/RANK interaction, to inhibit osteoclastic bone resorption and TRAIL-induced apoptosis in vitro and myeloma bone disease in vivo. OP3-4 inhibited osteoclast formation (P &lt; 0.01) and bone resorption (P &lt; 0.01) in vitro. However, OP3-4 had no effect on TRAIL-induced apoptosis of RPMI 8226 myeloma cells. Treatment of 5T2MM myeloma–bearing mice with OP3-4 decreased osteoclast number and the proportion of bone surface covered by osteoclasts (P &lt; 0.05). Treatment also prevented the tumor-induced decrease in cancellous bone area and the development of osteolytic lesions (P &lt; 0.05). OP3-4 also reduced tumor burden when compared with the control (P &lt; 0.05). These data suggest that OP3-4 and the selective inhibition of RANKL, but not TRAIL activity, are effective in preventing myeloma bone disease and offer a novel therapeutic approach to treating this aspect of myeloma. [Cancer Res 2007;67(1):202–8]
Dominant-Negative Fas Mutation Is Reversed by Down-expression of c-FLIP
Authors: Bénéteau Marie , Daburon Sophie , Moreau Jean-François , Taupin Jean-Luc , Legembre Patrick 
Published: January 2007

Abstract
Fas triggering by agonistic antibodies or by its cognate ligand, FasL, induces apoptotic cell death, whereas mutation in the Fas death domain is associated with lymphoma progression. On prolonged culture in the presence of an agonistic anti-Fas antibody, we raised a Jurkat cell line resistant to agonistic antibodies but still sensitive to soluble FasL, which carried at the heterozygous state, a point mutation into the Fas death domain. Down-modulation of c-FLIP expression reversed the blockade of the Fas pathway. We show that the activation threshold for the Fas receptor is more easily overcome by multimeric FasL than by agonistic antibodies and that the increase of this threshold due to mutation in the Fas death domain can be overcome by acting on a downstream effector of the Fas signal, c-FLIP. These findings put forward a new approach to eradicate Fas-resistant tumor cells. [Cancer Res 2007;67(1):108–15]
Gene Expression Profiling Reveals a Massive, Aneuploidy-Dependent Transcriptional Deregulation and Distinct Differences between Lymph Node–Negative and Lymph Node–Positive Colon Carcinomas
Authors: Grade Marian , Hörmann Patrick , Becker Sandra , Hummon Amanda B. , Wangsa Danny , Varma Sudhir , Simon Richard , Liersch Torsten , Becker Heinz , Difilippantonio Michael J. , Ghadimi B. Michael , Ried Thomas 
Published: January 2007

Abstract
To characterize patterns of global transcriptional deregulation in primary colon carcinomas, we did gene expression profiling of 73 tumors [Unio Internationale Contra Cancrum stage II (n = 33) and stage III (n = 40)] using oligonucleotide microarrays. For 30 of the tumors, expression profiles were compared with those from matched normal mucosa samples. We identified a set of 1,950 genes with highly significant deregulation between tumors and mucosa samples (P &lt; 1e−7). A significant proportion of these genes mapped to chromosome 20 (P = 0.01). Seventeen genes had a &gt;5-fold average expression difference between normal colon mucosa and carcinomas, including up-regulation of MYC and of HMGA1, a putative oncogene. Furthermore, we identified 68 genes that were significantly differentially expressed between lymph node–negative and lymph node–positive tumors (P &lt; 0.001), the functional annotation of which revealed a preponderance of genes that play a role in cellular immune response and surveillance. The microarray-derived gene expression levels of 20 deregulated genes were validated using quantitative real-time reverse transcription-PCR in &gt;40 tumor and normal mucosa samples with good concordance between the techniques. Finally, we established a relationship between specific genomic imbalances, which were mapped for 32 of the analyzed colon tumors by comparative genomic hybridization, and alterations of global transcriptional activity. Previously, we had conducted a similar analysis of primary rectal carcinomas. The systematic comparison of colon and rectal carcinomas revealed a significant overlap of genomic imbalances and transcriptional deregulation, including activation of the Wnt/β-catenin signaling cascade, suggesting similar pathogenic pathways. [Cancer Res 2007;67(1):41–56]