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41.
Donor CD4+ and CD8+ T cells mediate graft-vs.-leukemia (GVL) responses in the allogeneic bone marrow transplantation (alloBMT) setting. To evaluate the role of functional T cell subsets in the mediation of GVL, alloreactive donor CD4+ (Th1/Th2) and CD8+ (Tc1/Tc2) T cells of defined cytokine phenotype were generated by in vitro culture. A leukemia/transplantation model (B6 into B6C3F1; 1050 cGy host irradiation) was established using the bcr/abl-transfected myeloid leukemia line, 32Dp210 (P210; H-2k). Leukemia control mice (1X10(4) P210 cells per recipient) died at day 12.0 post-BMT. Recipients of the CD4+, Th1-type or CD8+, Tc1-type populations were conferred a survival advantage (death at 20.7 and 23.5 days post-BMT, respectively). In contrast, the CD4+, Th2-type population did not mediate GVL (death at 12.3 days). Furthermore, cell mixing experiments demonstrated that the Th2 subset abrogated both Th1- and Tc1-mediated GVL. The CD8+, Tc2 population, which secreted type II cytokines and lysed the P210 leukemia target in vitro, mediated GVL in some experiments; interestingly, the magnitude of Tc2-mediated GVL was inversely related to the level of interleukin-10 (IL-10) secreted in vitro by the Tc2 population. These studies therefore indicate that alloreactive T cells of type I phenotype maximally generate GVL, and that type I/type II interactions are an important consideration for allogeneic transplantation in the setting of leukemic hosts. 相似文献
42.
TG Evans W Bonnez HR Soucier T Fitzgerald DC Gibbons RC Reichman 《Canadian Metallurgical Quarterly》1998,39(3):163-173
Criteria for detection of chromosome aberrations by Comparative Genomic Hybridization (CGH) are not standardized and improvement of this part of the analysis is of paramount importance to the applicability of the technique. The aim of this work was to suggest CGH detection criteria that increase the specificity and sensitivity and at the same time include chromosome regions previously excluded from CGH analysis. We analyzed 33 hybridizations with normal DNA and modified our CGH software in order to use a selection of these normal analyses as a model for interpretation of analyses of unknown samples. This approach was successfully tested on 14 samples with known aberrations. 相似文献
43.
N Majumdar P Bhattacharya DC Biswas RK Choudhury DM Nadkarni A Saxena 《Canadian Metallurgical Quarterly》1995,51(6):3109-3115
44.
JF Richmond S Lu JC Santoro J Weng SL Hu DC Montefiori HL Robinson 《Canadian Metallurgical Quarterly》1998,72(11):9092-9100
DNA vaccination is an effective means of eliciting strong antibody responses to a number of viral antigens. However, DNA immunization alone has not generated persistent, high-titer antibody and neutralizing antibody responses to human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein (Env). We have previously reported that DNA-primed anti-Env antibody responses can be augmented by boosting with Env-expressing recombinant vaccinia viruses. We report here that recombinant Env protein provides a more effective boost of DNA-initiated antibody responses. In rabbits primed with Env-expressing plasmids, protein boosting increased titer, persistence, neutralizing activity, and avidity of anti-Env responses. While titers increased rapidly after boosting, avidity and neutralizing activity matured more slowly over a 6-month period following protein boosting. DNA priming and protein immunization with HIV-1 HXB-2 Env elicited neutralizing antibody for T cell line-adapted, but not primary isolate, viruses. The most effective neutralizing antibody responses were observed after priming with plasmids which expressed noninfectious virus-like particles. In contrast to immunizations with HIV-1 Env, DNA immunizations with the influenza virus hemagglutinin glycoprotein did not require a protein boost to achieve high-titer antibody with good avidity and persistence. 相似文献
45.
46.
Hobbie KA Peterson ES Barton ML Waters KM Anderson KA 《Journal of laboratory automation》2012,17(4):275-283
Large collaborative centers are a common model for accomplishing integrated environmental health research. These centers often include various types of scientific domains (e.g., chemistry, biology, bioinformatics) that are integrated to solve some of the nation's key economic or public health concerns. The Superfund Research Center (SRP) at Oregon State University (OSU) is one such center established in 2008 to study the emerging health risks of polycyclic aromatic hydrocarbons while using new technologies both in the field and laboratory. With outside collaboration at remote institutions, success for the center as a whole depends on the ability to effectively integrate data across all research projects and support cores. Therefore, the OSU SRP center developed a system that integrates environmental monitoring data with analytical chemistry data and downstream bioinformatics and statistics to enable complete "source-to-outcome" data modeling and information management. This article describes the development of this integrated information management system that includes commercial software for operational laboratory management and sample management in addition to open-source custom-built software for bioinformatics and experimental data management. 相似文献
47.
Patricia A. Miguez Stephen A. Tuin Adam G. Robinson Joyce Belcher Prapaporn Jongwattanapisan Kimberly Perley Vinicius de Paiva Gon«alves Arash Hanifi Nancy Pleshko Elisabeth R. Barton 《International journal of molecular sciences》2021,22(6)
This study evaluated the direct effect of a phytochemical, hesperidin, on pre-osteoblast cell function as well as osteogenesis and collagen matrix quality, as there is little known about hesperidin’s influence in mineralized tissue formation and regeneration. Hesperidin was added to a culture of MC3T3-E1 cells at various concentrations. Cell proliferation, viability, osteogenic gene expression and deposited collagen matrix analyses were performed. Treatment with hesperidin showed significant upregulation of osteogenic markers, particularly with lower doses. Mature and compact collagen fibrils in hesperidin-treated cultures were observed by picrosirius red staining (PSR), although a thinner matrix layer was present for the higher dose of hesperidin compared to osteogenic media alone. Fourier-transform infrared spectroscopy indicated a better mineral-to-matrix ratio and matrix distribution in cultures exposed to hesperidin and confirmed less collagen deposited with the 100-µM dose of hesperidin. In vivo, hesperidin combined with a suboptimal dose of bone morphogenetic protein 2 (BMP2) (dose unable to promote healing of a rat mandible critical-sized bone defect) in a collagenous scaffold promoted a well-controlled (not ectopic) pattern of bone formation as compared to a large dose of BMP2 (previously defined as optimal in healing the critical-sized defect, although of ectopic nature). PSR staining of newly formed bone demonstrated that hesperidin can promote maturation of bone organic matrix. Our findings show, for the first time, that hesperidin has a modulatory role in mineralized tissue formation via not only osteoblast cell differentiation but also matrix organization and matrix-to-mineral ratio and could be a potential adjunct in regenerative bone therapies. 相似文献
48.
3Z,6Z,9Z-Nonadecatriene (3Z,6Z,9Z-19:H; other abbreviations follow the same pattern) has been identified as a female sex pheromone component of the geometrid mothEpirrhoe sperryi (H.). 3Z,6Z,9Z-18:H and 6Z,9Z-19:H were also identified in pheromone gland extracts but had no apparent biological activity. 3Z,6Z,9Z-21:H was tentatively identified as a female sex pheromone component of a second geometrid species,Lobophora nivigerata (Wlk.). Attraction of male moths to this compound was strongly synergized by the addition of small amounts of 6Z,9Z-21:H to lures.Issued as NRC No. 32478. 相似文献
49.
E. W. Underhill J. G. Millar R. A. Ring J. W. Wong D. Barton M. Giblin 《Journal of chemical ecology》1987,13(6):1319-1330
A single sex pherormone component was isolated from abdominal tip extracts of female Bruce spanworm.Operophtera bruceata (Hulst). This was identified as (Z,Z,Z)-1,3,6,9-nonadecatetraene by capillary gas chromatography (GC), electroantennography, and mass spectrometry. In addition, hexane extracts of female abdominal tips from Bruce spanworm and the winter moth.O. brumata L., were analyzed by GC coupled to an electroantennographic detector (GC-EAD). The extracts ofO. bruceata andO. brumata females elicited only a single response, at the same retention time, from antennae of their conspecific and reciprocal males. In field tests conducted in Saskatchewan, traps baited with the synthetic tetraene captured Bruce spanworm males. In tests carried out on Vancouver Island, British Columbia, where the two species coexist, both Bruce spanworm and winter moth males were captured. The attractancy of lures containing the synthetic pheromone alone and in combination with several structurally related analogs was field tested at both locations. One of these, an isomer of the natural pheromone, (E,Z,Z)-1,3,6,9-nonadecatetraene, inhibited the capture of Bruce spanworm males but had no effect upon the number of winter moth males which were taken. Thus, populations of these two very similar species can be distinguished by employing traps baited with pheromone ± the inhibitor. Coneorifice Hara traps were found useful for field trapping males of both species.Issued as NRCC No. 26107 相似文献
50.
Barton B Rhinow D Walter A Schröder R Benner G Majorovits E Matijevic M Niebel H Müller H Haider M Lacher M Schmitz S Holik P Kühlbrandt W 《Ultramicroscopy》2011,111(12):1696-1705
We report the implementation of an electrostatic Einzel lens (Boersch) phase plate in a prototype transmission electron microscope dedicated to aberration-corrected cryo-EM. The combination of phase plate, Cs corrector and Diffraction Magnification Unit (DMU) as a new electron-optical element ensures minimal information loss due to obstruction by the phase plate and enables in-focus phase contrast imaging of large macromolecular assemblies. As no defocussing is necessary and the spherical aberration is corrected, maximal, non-oscillating phase contrast transfer can be achieved up to the information limit of the instrument. A microchip produced by a scalable micro-fabrication process has 10 phase plates, which are positioned in a conjugate, magnified diffraction plane generated by the DMU. Phase plates remained fully functional for weeks or months. The large distance between phase plate and the cryo sample permits the use of an effective anti-contaminator, resulting in ice contamination rates of <0.6 nm/h at the specimen. Maximal in-focus phase contrast was obtained by applying voltages between 80 and 700 mV to the phase plate electrode. The phase plate allows for in-focus imaging of biological objects with a signal-to-noise of 5-10 at a resolution of 2-3 nm, as demonstrated for frozen-hydrated virus particles and purple membrane at liquid-nitrogen temperature. 相似文献