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排序方式: 共有311条查询结果,搜索用时 31 毫秒
31.
Characterization of the γδ T cell response to acute leukemia 总被引:1,自引:0,他引:1
Meeh PF King M O'Brien RL Muga S Buckhalts P Neuberg R Lamb LS 《Cancer immunology, immunotherapy : CII》2006,55(9):1072-1080
Background: Previous work from our center has suggested a correlation between increased donor-derived Vδ1+ γδ T cells and long-term relapse-free survival following bone marrow transplantation for leukemia. Questions remain, however, as to whether this observation can be explained by a γδ T cell-based immune response against primary leukemia. Methods: We examined γδ T cell receptor (TCR) phenotype, cell proliferation, and cytolytic activity following culture with irradiated primary leukemia blasts from a haploidentical first-degree relative. Subsequently, we also studied the γδ TCR phenotype and complimentarity determining region 3 (CDR3) cDNA sequences from 17 newly diagnosed leukemia patients. Results: In 17/28 (61%) of in vitro cultures, γδ T cells proliferated in culture with primary blasts. Vδ1+ T cells were proportionally increased in all cultures and were the predominant cell population in 6/17. In the 7 cultures where cytotoxicity could be assessed, 6 (86%) showed some degree of cytotoxicity to the primary leukemia. Vδ1+ T cells were also the predominant γδ T cell subtype in pre-treatment leukemia patients principally due to loss of Vδ2+ T cells rather than expansion of Vδ1+ cells. The Vδ1 CDR3-region cDNA sequence from these patients revealed exclusive use of the Jδ1 constant region and sequence conservation in 4/11 patients. Conclusions: γδ T cells exhibit an in vitro response to primary leukemia blasts that is manifested by proliferation, an increased proportion of Vδ1+ T cells, and cytotoxicity to the primary leukemia blasts. The Vδ1+ T cell population is also predominant in newly diagnosed leukemia patients likely due to a loss of circulating Vδ2+ T cells. A small proportion of newly diagnosed patients showed Vδ1 CDR3 region similarity. These findings suggest a role for γδ T cells in the immune response to leukemia.Paul F. Meeh and Michelle King are contributed equally to this work. 相似文献
32.
UCP3 has been postulated to function in the defense against lipid-induced oxidative muscle damage (lipotoxicity). We explored this hypothesis during cachexia in rats (zymosan-induced sepsis), a condition characterized by increased oxidative stress and supply of fatty acids to the muscle. Muscle UCP3 protein content was increased 2, 6 and 11 days after zymosan injection. Plasma FFA levels were increased at day 2, but dropped below control levels on days 6 and 11. Muscular levels of the lipid peroxidation byproduct 4-hydroxy-2-nonenal (4-HNE) were increased at days 6 and 11 in zymosan-treated rats, supporting a role for UCP3 in modulating lipotoxicity during cachexia. 相似文献
33.
Nilsson T Malkiewicz K Gabrielsson M Folkesson R Winblad B Benedikz E 《Biochemical and biophysical research communications》2006,341(4):1294-1299
Alzheimer's disease is a neurodegenerative disorder characterised by extracellular accumulation of the Abeta peptide, derived from the amyloid precursor protein (APP). The function of APP as a cell surface receptor was examined by ligand-mimicking using an antibody against the APP extracellular domain. Alterations in gene expression evoked by antibody-bound APP were analysed using human pathway-finder gene arrays and the largest change in expression levels was found for ornithine decarboxylase (ODC). These results were confirmed by Western blotting which showed even higher upregulation on the protein level. APP knockdown by RNAi verified that upregulation of ODC was APP-mediated. This APP signalling event did not require gamma-secretase cleavage, as it was independent of the presence of presenilin-1 or -2. The induced ODC expression was rapid and biphasic, resembling growth-factor stimulated signalling events. This study shows that antibody-bound APP leads to altered gene expression that may be relevant to AD. 相似文献
34.
Liebrand TW Smit P Abd-El-Haliem A de Jonge R Cordewener JH America AH Sklenar J Jones AM Robatzek S Thomma BP Tameling WI Joosten MH 《Plant physiology》2012,159(4):1819-1833
Cf proteins are receptor-like proteins (RLPs) that mediate resistance of tomato (Solanum lycopersicum) to the foliar pathogen Cladosporium fulvum. These transmembrane immune receptors, which carry extracellular leucine-rich repeats that are subjected to posttranslational glycosylation, perceive effectors of the pathogen and trigger a defense response that results in plant resistance. To identify proteins required for the functionality of these RLPs, we performed immunopurification of a functional Cf-4-enhanced green fluorescent protein fusion protein transiently expressed in Nicotiana benthamiana, followed by mass spectrometry. The endoplasmic reticulum (ER) heat shock protein70 binding proteins (BiPs) and lectin-type calreticulins (CRTs), which are chaperones involved in ER-quality control, were copurifying with Cf-4-enhanced green fluorescent protein. The tomato and N. benthamiana genomes encode four BiP homologs and silencing experiments revealed that these BiPs are important for overall plant viability. For the three tomato CRTs, virus-induced gene silencing targeting the plant-specific CRT3a gene resulted in a significantly compromised Cf-4-mediated defense response and loss of full resistance to C. fulvum. We show that upon knockdown of CRT3a the Cf-4 protein accumulated, but the pool of Cf-4 protein carrying complex-type N-linked glycans was largely reduced. Together, our study on proteins required for Cf function reveals an important role for the CRT ER chaperone CRT3a in the biogenesis and functionality of this type of RLP involved in plant defense. 相似文献
35.
Nikolaidis PT Ziv G Arnon M Lidor R 《Journal of strength and conditioning research / National Strength & Conditioning Association》2012,26(9):2547-2557
The purpose of this study was twofold: (a) to profile physical characteristics and physiological attributes of adolescent and adult Greek female volleyball players (n = 61) who were members of the A (the best league for female volleyball players) and B (the second-best league for female volleyball players) Series clubs in Greece and (b) to examine the intraindividual variability among these players in all physical and physiological measurements that were undertaken in the study. The participants were divided into 3 age groups--under 14, 14-18, and over 18 years. They underwent a series of physical (e.g., height, body mass, and percentage of body fat) and physiological (e.g., aerobic profile, flexibility, and vertical jumping ability) tests. Three main findings emerged from the data analysis: (a) differences in physical characteristics and physiological attributes existed between the 3 age groups. For example, fat-free mass was lower in players under the age of 14 years (41.57 ± 6.06 kg) compared with that in players between the ages of 14-18 years (50.24 ± 6.96 kg) and players over the age of 18 years (52.03 ± 3.39 kg). In addition, the relative peak power as measured in the Wingate Anaerobic Test was the highest in the over-18 group (9.72 ± 0.65 W·kg), lower in the 14-18 group (8.95 ± 0.7), and the lowest in the under-14 group (8.32 ± 0.78 W·kg), (b) large intraindividual variability existed in most physical characteristics and physiological attributes measured in the study, and (c) the intraindividual variability was observed in all the 3 groups. These findings emphasize the need for coaches to examine the intraindividual variability within the players on their teams and to use this information when designing training programs and strength and conditioning programs. 相似文献
36.
José Ronnie Vasconcelos Oscar Bru?a–Romero Adriano F. Araújo Mariana R. Dominguez Jonatan Ersching Bruna C. G. de Alencar Alexandre V. Machado Ricardo T. Gazzinelli Karina R. Bortoluci Gustavo P. Amarante-Mendes Marcela F. Lopes Mauricio M. Rodrigues 《PLoS pathogens》2012,8(5)
MHC class Ia-restricted CD8+ T cells are important mediators of the adaptive immune response against infections caused by intracellular microorganisms. Whereas antigen-specific effector CD8+ T cells can clear infection caused by intracellular pathogens, in some circumstances, the immune response is suboptimal and the microorganisms survive, causing host death or chronic infection. Here, we explored the cellular and molecular mechanisms that could explain why CD8+ T cell-mediated immunity during infection with the human protozoan parasite Trypanosoma cruzi is not optimal. For that purpose, we compared the CD8+ T-cell mediated immune responses in mice infected with T. cruzi or vaccinated with a recombinant adenovirus expressing an immunodominant parasite antigen. Several functional and phenotypic characteristics of specific CD8+ T cells overlapped. Among few exceptions was an accelerated expansion of the immune response in adenoviral vaccinated mice when compared to infected ones. Also, there was an upregulated expression of the apoptotic-signaling receptor CD95 on the surface of specific T cells from infected mice, which was not observed in the case of adenoviral-vaccinated mice. Most importantly, adenoviral vaccine provided at the time of infection significantly reduced the upregulation of CD95 expression and the proapoptotic phenotype of pathogen-specific CD8+ cells expanded during infection. In parallel, infected adenovirus-vaccinated mice had a stronger CD8 T-cell mediated immune response and survived an otherwise lethal infection. We concluded that a suboptimal CD8+ T-cell response is associated with an upregulation of CD95 expression and a proapoptotic phenotype. Both can be blocked by adenoviral vaccination. 相似文献
37.
Wang C Nagornyak E Das R Pollack GH 《Computer methods in biomechanics and biomedical engineering》2008,11(6):609-614
Motile systems exhibit a stepwise nature, seen most prominently in muscle contraction. A novel algorithm has been developed that detects steps automatically in sarcomere-length change data and computes their size. The method is based on a nonlinear filter and a step detection protocol that detects local slope values in comparison to a threshold. The algorithm was first evaluated using artificial data with various degrees of Gaussian noise. Steps were faithfully detected even with significant noise. With actual data, the algorithm detected 2.7 nm steps and integer multiples thereof. The results confirm a quantal 2.7 nm step-size reported earlier. As stepwise phenomena become increasingly evident, automatic step-detection algorithms become increasingly useful since the limiting factor is almost always noise. The algorithm presented here offers a versatile and accurate tool that should be useful not only within muscle contraction and motility fields, but in fields which quantal phenomena play a role. 相似文献
38.
A study of the microbial quality of grey water and an evaluation of treatment technologies for reuse
Gideon P. Winward Lisa M. Avery Ronnie Frazer-Williams Marc Pidou Paul Jeffrey Tom Stephenson Bruce Jefferson 《Ecological Engineering》2008,32(2):187-197
The reuse of grey water for non-potable water applications is a potential solution for water-deprived regions worldwide. Adequate treatment of grey water prior to reuse is important to reduce the risks of pathogen transmission and to improve the efficacy of subsequent disinfection. This study investigated the presence of common pathogens in grey water and compared the pathogen removal performance of leading contender treatment technologies. The opportunistic pathogens Pseudomonas aeruginosa and Staphylococcus aureus were detected in the grey water tested. Three configurations of constructed wetland, a membrane bioreactor (MBR), and a membrane chemical reactor (MCR) were evaluated for indicator bacteria (total coliforms, Escherichia coli, Enterococci, Clostridia, and heterotrophs) removal over a period of 2 years under conditions of low and high strength grey water influent. Total coliforms were found to be good indicators for P. aeruginosa, showing strong and significant Spearman's rank correlations in the influent grey water (rs = 0.77, P = 0.005) and treated effluents (rs = 0.81, P ≤ 0.001). The MBR provided the highest quality treated effluent and was the most robust treatment technology, remaining unaffected by an increase in influent grey water strength. Of the three constructed wetlands, the VFRB was the most reliable performer under low and high strength influent conditions, indicating aerobic unsaturated wetland to be the most suitable form of the technology for pathogen removal. 相似文献
39.
Xuan He Abishek Chandrashekar Roland Zahn Frank Wegmann Jingyou Yu Noe B. Mercado Katherine McMahan Amanda J. Martinot Cesar Piedra-Mora Sidney Beecy Sarah Ducat Ronnie Chamanza Sietske Rosendahl Huber Marjolein van Heerden Leslie van der Fits Erica N. Borducchi Michelle Lifton Jinyan Liu Dan H. Barouch 《Cell》2021,184(13):3467-3473.e11
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40.
Membrane mass spectrometry (MMS) with reduced sample withdrawal has been used to investigate the metabolic activity of yeast cells immobilised in porous glass. An adapted MS membrane inlet reactor with a polyethylene terephthalate barrier membrane has been constructed for this purpose. In a first experiment, the mass transport of O2 in a porous glass disc under well-defined experimental conditions has been studied by determining the apparent effective diffusion coefficient. The behaviour of immobilised Saccharomyces cerevisiae has been monitored by the MMS measurement of O2 and CO2 after applying a step in glucose concentration. Free-cell kinetic parameters were used in a dynamic reaction-diffusion model to simulate the O2 consumption curve. The theoretical and experimental curve showed comparable behaviour, which means that the immobilisation of yeast cells in porous glass has no substantial effect on its growth kinetics. 相似文献