bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rapid differentiation of current infectious bronchitis virus vaccine strains and field isolates in Australia
Authors: MARDANI K. , BROWNING GF , IGNJATOVIC J. , NOORMOHAMMADI AH 
Published: June 2007

Objective Rapid differentiation of vaccine strains of infectious bronchitis virus (IBV) from wild type strains would enhance investigations of disease outbreaks. This study aimed to develop a reverse transcription‐polymerase chain reaction (RT‐PCR) assay to differentiate between Australian vaccine strains of IBV and field isolates. Procedure A fragment of 6.5 kilobases that contains the S, M and N genes was amplified by RT‐PCR from ten different IBV strains, including vaccine strains and field isolates, and then sequenced. Results Comparison of the sequences of these strains revealed a deletion of 58 bases in the 3′ untranslated region (UTR) of IBV vaccine strains but not in the field isolates. Two primers were designed to amplify a fragment of the 3′ UTR that differed in size between the vaccine strains and field isolates. RT‐PCR was performed using these two primers to screen 20 IBV strains, including field isolates and the vaccine strains. All strains were correctly identified as either vaccine strains or field isolates. Conclusion This procedure is a rapid, sensitive and inexpensive method for discrimination between most current Australian vaccine strains and field isolates of IBV.
Porcine Circovirus 2 Replication in Colostrum‐deprived Piglets Following Experimental Infection and Immune Stimulation Using A Modified Live Vaccine against Porcine Respiratory and Reproductive Syndrome Virus
Authors: Allan G. M. , Caprioli A. , McNair I. , Lagan‐Tregaskis P. , Ellis J. , Krakowka S. , McKillen J. , Ostanello F. , McNeilly F. 
Published: June 2007

SummaryPorcine circovirus type 2 (PCV2) infection is now recognized as the major factor in the development of post‐weaning multisystemic wasting syndrome (PMWS). Although Koch’s postulates have been fulfilled for PCV2 and PMWS, the severe clinical expression of the disease observed in field cases has been difficult to reproduce experimentally. Some studies have demonstrated that immune stimulation associated with the use of some commercially available swine vaccines may trigger progression of PCV2 infection to disease and lesions characteristic of PMWS. Here we describe the effects on PCV2 infection in an experimental model following the use of a commercially available modified live vaccine to porcine respiratory and reproductive syndrome virus (PRRSV). Although none of the piglets infected with PCV2 developed clinical PMWS, the severity of microscopical lesions and the PCV2 antigen load associated with these lesions were higher in the PRRSV‐vaccinated piglets compared with those detected in the PCV2 only infected animals.
Constraints to Microbial Food Safety Policy: Opinions from Stakeholder Groups along the Farm to Fork Continuum
Authors: Sargeant J. M. , Ramsingh B. , Wilkins A. , Travis R. G. , Gavrus D. , Snelgrove J. W. 
Published: June 2007

SummaryThis exploratory qualitative study was conducted to identify constraints to microbial food safety policy in Canada and the USA from the perspective of stakeholder groups along the farm to fork continuum. Thirty‐seven stakeholders participated in interviews or a focus group where semi‐structured questions were used to facilitate discussion about constraints to policy development and implementation. An emergent grounded theory approach was used to determine themes and concepts that arose from the data (versus fitting the data to a hypothesis or a priori classification). Despite the plurality of stakeholders and the range of content expertise, participant perceptions emerged into five common themes, although, there were often disagreements as to the positive or negative attributes of specific concepts. The five themes included challenges related to measurement and objectives of microbial food safety policy goals, challenges arising from lack of knowledge, or problems with communication of knowledge coupled with current practices, beliefs and traditions; the complexity of the food system and the plurality of stakeholders; the economics of producing safe food and the limited resources to address the problem; and, issues related to decision‐making and policy, including ownership of the problem and inappropriate inputs to the decision‐making process. Responsibilities for food safety and for food policy failure were attributed to all stakeholders along the farm to fork continuum. While challenges regarding the biology of food safety were identified as constraints, a broader range of policy inputs encompassing social, economic and political considerations were also highlighted as critical to the development and implementation of effective food safety policy. Strategies to address these other inputs may require new, transdisciplinary approaches as an adjunct to the traditional science‐based risk assessment model.
Influence of Communal Alpine Pasturing on the Spread of Pestiviruses among Sheep and Goats in Austria: First Identification of Border Disease Virus in Austria
Authors: Krametter‐Froetscher R. , Kohler H. , Benetka V. , Moestl K. , Golja F. , Vilcek S. , Baumgartner W. 
Published: June 2007

SummaryThe purpose of this investigation was to determine the influence of communal Alpine pasturing on the spread of pestivirus infections among sheep and goats. The study included 481 sheep from 23 farms and 131 goats from 26 farms pastured on separated Alpine meadows in the western part of Austria. At the starting of pasturing on the sheep meadow, 325 (67.6%) animals were seropositive, on the goat meadows in 16 (12.2%) samples antibodies to pestiviruses were detected. At the end of pasturing, 74 seronegative sheep and two seronegative goats had seroconverted. Between the beginning and the end of pasturing the seroprevalence in sheep increased significantly from 67.6% to 83% (P < 0.05). Moreover, in the peripheral blood mononuclear cells of four sheep, pestivirus‐specific RNA was detected before as well as after pasturing; these animals remained serologically negative throughout the investigation. They were, therefore, identified as persistently infected. Sequence analysis in the Npro region revealed that the detected pestiviruses were the same at genetic level and they were grouped into the Border disease virus (BDV)‐3 genotype. No pestivirus RNA was found in goat samples. The results of this survey indicate that communal Alpine pasturing does play a key role in the spread of BDV. Moreover, BDV has been identified and characterized for the first time in sheep in Austria, which until then had been regarded as being free from BD.
Light and electron microscopic observations of the infection of Camellia sasanqua by the fungus Exobasidum camelliae var. gracilis
Authors: Mims C.W. , Richardson E.A. 
Published: June 2007

Only a very small percentage of the shoots of the numerous Camellia sasanqua Thunb. plants examined in this study were infected by Exobasidium camelliae var. gracilis Shirai, and prior to the onset of new leaf formation in the spring, it was impossible to distinguish these shoots from healthy shoots with the naked eye. However, beginning in early April, an infected shoot gave rise to a group of tightly clustered, pale-green leaves that were significantly larger and thicker than the dark-green healthy leaves. Light and transmission electron microscopic observations revealed the presence of intercellular hyphae of E. camelliae var. gracilis in the apical meristems of shoots that gave rise to enlarged infected leaves. Very slender intercellular hyphae were observed between the tightly packed cells of the apical meristem as well as between the cells of the tunica that covered the meristem. Hyphae also filled many of the intercellular spaces in the stem immediately below the apical meristem. Some hyphae formed distinctive haustoria that protruded for short distances into the invaded host cells. Hyphae also were present in the leaf primordia and proliferated in the intercellular spaces while the primordium differentiated into a leaf. Eventually a distinct pseudoparenchymatous layer of intercellular hyphae developed some four to six cell layers above the lower epidermis. This layer then gave rise to the basidia that made up the hymenium of E. camelliae var. gracilis. As basidia developed, the underlying cell layers of the leaf separated from the overlying hymenium and eventually sloughed away to expose the basidia. Localized infections of random leaves also were observed. In many cases only a small part of a leaf was infected. Localized infections also culminated in successful hymenium development.
The effect of growing season length and water level fluctuations on growth and survival of two rare and at risk Atlantic Coastal Plain flora species, Coreopsis rosea and Hydrocotyle umbellata
Authors: Lusk Jennifer M. , Reekie Edward G. 
Published: June 2007

This study examined variables that may be limiting rare species of Nova Scotia’s Coastal Plain flora to determine why they have not expanded to other lakeshores, including dam reservoirs with appropriate slope and substrate, and to determine how reservoir management could improve habitat quality. A transplant experiment was conducted to examine whether variables related to growing season (establishment time, position on shoreline, and water-level fluctuation) were limiting two at-risk species, Coreopsis rosea Nutt. (Pink Tickseed) and Hydrocotyle umbellata L. (Water-pennywort). Establishment time as well as timing and duration of flooding were found to limit both species. Unseasonable flooding and later establishment had similar effects in reducing biomass. The contribution of time spent above water to the final biomass was 2–3.4 times greater than time spent below water. At reservoirs, earlier spring draw down would reduce flood stress, while opening the dam during periods of high precipitation would avoid plant damage due to unseasonable flooding. Exposure of the lower shoreline for 49–71 d or greater would benefit H. umbellata, and exposure of the upper shoreline for 100–112 d or greater would benefit C. rosea. To conserve current habitat, we must also minimize disturbances to watersheds affecting natural fluctuations of occupied lakes.
Correlated effects of selection for flower size in Raphanus raphanistrum
Authors: Lehtilä Kari , Holmén Bränn Kristina 
Published: June 2007

The evolution of flower size may be constrained by trade-offs between flower size and other plant traits. The aim of this study was to determine how selection on flower size affects both reproductive and vegetative traits. Raphanus raphanistrum L. was used as the study species. Artificial selection for small and large petal size was carried out for two generations. We measured the realized heritability of flower size and recorded flower production, time to flowering, plant size, and seed production in the two selection lines. The realized heritability was h2 = 0.49. Our study, therefore, showed that R. raphanistrum has potential for rapid evolutionary change of floral size. The lines with large flowers produced smaller seeds and started to flower later than the lines with small flowers. There was no trade-off between flower size and flower number, but the lines selected for large flower size had more flowers and a larger plant size than lines selected for small flowers. Estimates of restricted maximum likelihood (REML) analysis of pedigrees also showed that flower size had a positive genetic correlation with start of flowering and plant height.
Properties and general use of the X-ray elastic factors
Authors: Ortner Balder 
Published: June 2007

The equation ε(φ, ψ, hkl)=Fij(φ, ψ, hkl)σij can be directly deduced from Hooke’s law. It is shown that the matrix Fij(φ, ψ, hkl) which is usually called X-ray elastic factors, behaves as a second rank tensor. Since this behaviour is the only criterion for the question of whether or not it is a tensor, the F-matrix must be regarded as a second rank tensor. This allows us to make some statements about the structure of the F-matrix on the basis of Neumann’s principle, to find relationships among F-matrices in different measurement directions, and to apply the methods and strategies for the measurement of a second rank tensor. All this is shown in a few examples. It is further shown that a consistent use of the F-matrix can replace all methods for data evaluation which makes use of linear regressions and, in addition, avoids all difficulties and disadvantages of these methods. One of these disadvantages is that the sin2 ψ-method, as well as its derivatives, is generally not correct least square fits of the measured data. This is also shown in an example. The more complicated cases with stress or constitution gradients in the range of the probed volume or stress measurement after plastic deformation are not discussed.
Unit cell expansion in ErT2 films
Authors: Rodriguez Mark A. , Browning James F. , Frazer Colleen S. , Snow Clark S. , Tissot Ralph G. , Boespflug Elaine P. 
Published: June 2007

XRD analysis of plasma-vapor-deposited
ErT2 films during aging (T decay to
3He) reveals an hkl-dependent unit-cell expansion in which (200) grains expand out-of-plane as much as 0.01 Å more than (111) out-of-plane grains. Texture analysis of an aged
ErT2 film reveals a bimodal (111)/(200) out-of-plane preferred orientation. sin2 ψ analysis reveals significant in-plane macro-strain due to
3He
bubble formation/growth. The mechanistic origins regarding these observations are also discussed.
A Combination Hybrid-Based Vaccination/Adoptive Cellular Therapy to Prevent Tumor Growth by Involvement of T Cells
Authors: Savai Rajkumar , Schermuly Ralph Theo , Pullamsetti Soni Savai , Schneider Michael , Greschus Susanne , Ghofrani Hossein Ardeschir , Traupe Horst , Grimminger Friedrich , Banat Gamal-Andre 
Published: June 2007

AbstractCancer immunotherapy with dendritic cell–tumor cell fusion hybrids induces polyclonal stimulation against a variety of tumor antigens, including unknown antigens. Hybrid cells can prime CTLs, which subsequently develop antitumor responses. The aim of this study was to enhance the known antitumor effect of hybrid vaccination (HC-Vacc) and hybrid-primed adoptive T-cell therapy (HC-ACT) using the poorly immunogenic Lewis lung carcinoma (LLC1) model. The strategy used was a combination of a double HC-Vacc alternating with HC-ACT (HC-Vacc/ACT). Using flat-panel volumetric computer tomography and immunohistochemistry, we showed a significant retardation of tumor growth (85%). In addition, a significant delay in tumor development, a reduction in the number of pulmonary metastases, and increased survival times were observed. Furthermore, the tumors displayed significant morphologic changes and increased apoptosis, as shown by up-regulation of gene expression of the proapoptotic markers Fas, caspase-8, and caspase-3. The residual tumor masses seen in the HC-Vacc/ACT–treated mice were infiltrated with CD4+ and CD8+ lymphocytes and showed elevated IFNγ expression. Moreover, splenic enlargement observed in HC-Vacc/ACT–treated mice reflected the increased functionality of T cells, as also indicated by increased expression of markers for CTL activation, differentiation, and proliferation (Cd28, Icosl, Tnfrsf13, and Tnfsf14). Our findings indicate that the combination therapy of dendritic cell–tumor cell HC-Vacc/ACT is a very effective and a promising immunotherapeutic regimen against poorly immunogenic carcinomas. [Cancer Res 2007;67(11):5444–54]
Polychlorinated Biphenyl Levels in Peripheral Blood and Non-Hodgkin's Lymphoma: A Report from Three Cohorts
Authors: Engel Lawrence S. , Laden Francine , Andersen Aage , Strickland Paul T. , Blair Aaron , Needham Larry L. , Barr Dana B. , Wolff Mary S. , Helzlsouer Kathy , Hunter David J. , Lan Qing , Cantor Kenneth P. , Comstock George W. , Brock John W. , Bush David , Hoover Robert N. , Rothman Nathaniel 
Published: June 2007

Abstract
The incidence of non-Hodgkin's lymphoma (NHL) unrelated to HIV infection has steadily increased over the past several decades and remains substantially unexplained. Limited evidence suggests that increased concentrations of polychlorinated biphenyls (PCB) measured in blood or fat tissue are associated with increased risk of NHL. Although PCB congeners vary in their biological activity, the relation between individual congeners and NHL risk has not been examined previously using prospectively collected biospecimens. We examined congener-specific associations in three prospective cohorts. Prediagnostic serum or plasma concentrations of selected PCB congeners were measured among NHL cases and controls from these cohorts: Janus (190 cases and 190 controls) in Norway and CLUE I (74 cases and 147 controls) and the Nurses' Health Study (30 cases and 78 controls) in the United States. All blood samples were collected in the 1970s or 1980s. We used logistic regression to calculate odds ratios (OR) and 95% confidence intervals (95% CI) for the relations between risk of NHL and lipid-corrected plasma or serum concentrations. Several congeners (i.e., 118, 138, and 153) that were present at higher levels and were moderately to highly correlated with each other showed exposure-response trends with risk of NHL in all three cohorts. These associations were observed primarily among subjects diagnosed closer to the date of blood collection in the two cohorts with sufficient cases to permit stratification by time. Among cases diagnosed within the median years of follow-up (16 years in Janus and 12 years in CLUE I), ORs and 95% CIs for increasing fourths of concentration of congener 118 relative to the lowest fourth were as follows: 2.4 (0.9–6.5), 4.9 (1.6–15.3), and 5.3 (1.5–18.8; Ptrend &lt; 0.005) in Janus and 8.1 (1.0–68.9), 6.6 (0.7–59.0), and 13.0 (1.6–106.8; Ptrend &lt; 0.05) in CLUE I. Similar patterns were seen for congeners 138 and 153 and for total PCBs. Limited evidence of exposure-response trends was also observed for several other congeners. The primary 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane metabolite, p,p′-DDE, was not significantly associated with NHL in most analyses but slightly to moderately confounded the PCB associations. The results from these three cohorts suggest that concentrations of certain PCBs in blood are associated with increased risk of NHL. [Cancer Res 2007;67(11):5545–52]
A Role for the Fas/FasL System in Modulating Genetic Susceptibility to T-Cell Lymphoblastic Lymphomas
Authors: Villa-Morales María , Santos Javier , Pérez-Gómez Eduardo , Quintanilla Miguel , Fernández-Piqueras José 
Published: June 2007

AbstractThe Fas/FasL system mediates induced apoptosis of immature thymocytes and peripheral T lymphocytes, but little is known about its implication in genetic susceptibility to T-cell malignancies. In this article, we report that the expression of FasL increases early in all mice after γ-radiation treatments, maintaining such high levels for a long time in mice that resisted tumor induction. However, its expression is practically absent in T-cell lymphoblastic lymphomas. Interestingly, there exist significant differences in the level of expression between two mice strains exhibiting extremely distinct susceptibilities that can be attributed to promoter functional polymorphisms. In addition, several functional nucleotide changes in the coding sequences of both Fas and FasL genes significantly affect their biological activity. These results lead us to propose that germ-line functional polymorphisms affecting either the levels of expression or the biological activity of both Fas and FasL genes could be contributing to the genetic risk to develop T-cell lymphoblastic lymphomas and support the use of radiotherapy as an adequate procedure to choose in the treatment of T-cell malignancies. [Cancer Res 2007;67(11):5107–16]
Host Perforin Reduces Tumor Number but Does Not Increase Survival in Oncogene-Driven Mammary Adenocarcinoma
Authors: Street Shayna E.A. , Zerafa Nadeen , Iezzi Manuela , Westwood Jennifer A. , Stagg John , Musiani Piero , Smyth Mark J. 
Published: June 2007

AbstractThe concept of tumor immune surveillance has been supported by several recent studies in mice which show that immune effector mechanisms suppress hematologic malignancy. However, because the most common forms of human cancer are epithelial in origin, and comparatively very little data supports the immune surveillance of epithelial malignancies, we have chosen to evaluate the role of perforin-mediated cytotoxicity in the prevention of BALB/c Her2/neu-induced mammary cancer. Interestingly, perforin significantly delayed the onset of mammary tumorigenesis and reduced the number of mammary tumors without improving survival. Natural killer cell, but not CD8+ T cell, depletion resulted in a similar phenotype to perforin deficiency in this regard. Histologic analysis further indicated that the effect of perforin was most evident during the earliest stages of carcinogenesis rather than prior to or during the hyperplastic phase. This data suggests that perforin may mediate some suppression of epithelial carcinogenesis by intervening early in the tumor development process. [Cancer Res 2007;67(11):5454–60]
Apoptosis Suppression by Somatic Cell Transfer of Bcl-2 Promotes Sonic Hedgehog–Dependent Medulloblastoma Formation in Mice
Authors: McCall Todd D. , Pedone Carolyn A. , Fults Daniel W. 
Published: June 2007

AbstractMedulloblastomas are malignant brain tumors that arise in the cerebellum in children. Aberrant activation of the Sonic hedgehog (Shh) signaling pathway, which normally stimulates proliferation of granule neuron precursors (GNP) during cerebellar development, induces tumors in mice that closely mimic human medulloblastomas. Shh-dependent medulloblastoma formation is enhanced by hyperactive insulin-like growth factor (IGF) signaling and ectopic expression of Myc oncogenes. This enhanced tumorigenesis stems from the sensitivity of GNPs to IGF and Myc levels in regulating proliferation. An emerging theme in cancer research is that oncogene-induced cell proliferation cannot initiate neoplastic transformation unless cellular programs that mediate apoptosis are disabled. Here, we report a high frequency of medulloblastoma formation in mice after postnatal overexpression of the antiapoptotic protein Bcl-2 in cooperation with Shh. Ectopic expression of Bcl-2 alone or in combination with N-Myc did not induce tumors, indicating that Shh has essential transforming functions in GNPs not supplied by the mitogenic stimulus of N-Myc combined with a strong antiapoptotic signal provided by Bcl-2. Expression of endogenous Bcl-2 was not up-regulated in Shh-induced tumors. Instead, elevated levels of phosphorylated Akt were found, suggesting that activated phosphatidylinositol 3-kinase signaling is one intrinsic mechanism for suppressing apoptosis in Shh-dependent medulloblastomas. Thus, blockade of apoptosis cooperates with Shh-stimulated proliferation to transform GNPs and induce aggressive medulloblastomas. These findings provide insights into the molecular signals that initiate medulloblastoma formation and they support the importance of blocking apoptosis in carcinogenesis. [Cancer Res 2007;67(11):5179–85]