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排序方式: 共有346条查询结果,搜索用时 15 毫秒
41.
The human plasma protein β(2)-glycoprotein I (β(2)-GPI) is the major target of autoantibodies associated with antiphospholipid syndrome. However, the biologic function of this abundant protein is still unclear. Here we identify β(2)-GPI as a complement regulator. β(2)-GPI circulates in the plasma in an inactive circular form. On surface binding, such as to apoptotic cells, β(2)-GPI changes conformation to an elongated form that acquires C3/C3b binding activities. β(2)-GPI apparently changes conformation of C3, so that the regulator factor H attaches and induces subsequent degradation by the protease factor I. β(2)-GPI also mediates further cleavage of C3/C3b compared with factor H alone. Our data provide important insights into innate immune regulation by plasma protein β(2)-GPI, which may be exploited in the prevention and therapy of autoimmune disease antiphospholipid syndrome. 相似文献
42.
Clemente MJ Wlodarski MW Makishima H Viny AD Bretschneider I Shaik M Bejanyan N Lichtin AE His ED Paquette RL Loughran TP Maciejewski JP 《Blood》2011,118(16):4384-4393
T-cell large granular lymphocyte leukemia (T-LGLL) is characterized by chronic lymphoproliferation of cytotoxic T lymphocytes (CTLs) and is associated with lineage-restricted cytopenias. Introduction of T-cell receptor (TCR) variable β-chain (Vβ) monoclonal antibodies has facilitated identification and enumeration of clonal CTLs by flow cytometry. A highly skewed TCR Vβ repertoire identified by flow cytometry is strongly associated with monoclonal CDR3 regions by quantitative sequencing and positive TCRγ rearrangement assays. Therefore, Vβ expansions can serve as surrogate markers of CTL clonality to assess clonal kinetics in T-LGLL. We analyzed the TCR repertoire in 143 patients, 71 of which were available for serial measurements over 6 to 96 months. Although the majority (38/71, 54%) maintained a consistent monoclonal expansion, many (26/71, 37%) unexpectedly displayed a change in the dominant clone, whereby the original CTL clone contracted and another emerged as demonstrated by Vβ typing. Our results demonstrate that the T-cell repertoire is more dynamic in T-LGLL than recognized previously, illustrating the heterogeneity of disorders under this categorization. 相似文献
43.
Isabell D. Witzel Karin Milde-Langosch Ralph M. Wirtz Claudia Roth Maike Ihnen Sven Mahner Christine Zu Eulenburg Fritz Jänicke Volkmar Müller 《Journal of cancer research and clinical oncology》2010,136(11):1709-1718
Purpose
Prognostic and predictive markers in breast cancer are currently determined by single analysis of protein amounts. If RNA-based multi-gene analyses enter clinical practice, simultaneous determination of currently established markers like human epidermal growth factor receptor 2 (HER2), urokinase plasminogen activator (uPA) and its inhibitor (PAI-1) would represent an elegant simplification. To investigate the correlation between RNA and protein levels, we assessed HER2, uPA and PAI-1 in patients with breast cancer. In addition, we evaluated the influence of these factors on patient outcome. 相似文献44.
45.
Patterns and challenges of treatment sequencing in patients with hepatocellular carcinoma: Experience from a German referral center 下载免费PDF全文
46.
The Gibbon Ape Leukemia Virus envelope protein (GALV-Env) mediates efficient transduction of human cells, particularly primary B and T lymphocytes, and is therefore of great interest in gene therapy. Using internal domains from murine leukemia viruses (MLV), chimeric GALV-Env proteins such as GALV-C4070A were derived, which allow pseudotyping of lentiviral vectors. In order to improve expression efficiency and vector titers, we developed a codon-optimized (co) variant of GALV-C4070A (coGALV-Env). We found that coGALV-Env mediated efficient pseudotyping not only of γ-retroviral and lentiviral vectors, but also α-retroviral vectors. The obtained titers on HEK293T cells were equal to those with the classical GALV-Env, whereas the required plasmid amounts for transient vector production were significantly lower, namely, 20 ng coGALV-Env plasmid per 106 293T producer cells. Importantly, coGALV-Env-pseudotyped γ- and α-retroviral, as well as lentiviral vectors, mediated efficient transduction of primary human T cells. We propose that the novel chimeric coGALV-Env gene will be very useful for the efficient production of high-titer vector preparations, e.g., to equip human T cells with novel specificities using transgenic TCRs or CARs. The considerably lower amount of plasmid needed might also result in a significant cost advantage for good manufacturing practice (GMP) vector production based on transient transfection. 相似文献
47.
Wartenburger I Steinbrink J Telkemeyer S Friedrich M Friederici AD Obrig H 《NeuroImage》2007,34(1):416-425
Beyond its multiple functions in language comprehension and emotional shaping, prosodic cues play a pivotal role for the infant's amazingly rapid acquisition of language. However, cortical correlates of prosodic processing are largely controversial, even in adults, and functional imaging data in children are sparse. We here use an approach which allows to experimentally determine brain activations correlating to the perception and processing of sentence prosody during childhood. In 4-year-olds, we measured focal brain activation using near-infrared spectroscopy and demonstrate that processing prosody in isolation elicits a larger right fronto-temporal activation whereas a larger left hemispheric activation is elicited by the perception of normal language with full linguistic content. Hypothesized by the dual-pathway-model, the present data provide experimental evidence that in children specific language processes rely on interhemispheric specialization with a left hemispheric dominance for processing segmental (i.e. phonological) and a right hemispheric dominance for processing suprasegmental (i.e. prosodic) information. Generally in accordance with the imaging data reported in adults, our finding underlines the notion that interhemispheric specialization is a continuous process during the development of language. 相似文献
48.
Two‐Year Neurodevelopment and Growth Outcomes for Preterm Neonates Who Received Low‐Dose Intravenous Soybean Oil 下载免费PDF全文
Margaret L. Ong MD Isabell B. Purdy PhD Orly L. Levit MD Daniel T. Robinson MD Tristan Grogan MS Martiniano Flores MS Kara L. Calkins MD MS 《JPEN. Journal of parenteral and enteral nutrition》2018,42(2):352-360
Background: In some studies, the dose of intravenous soybean oil (SO) has been associated with a decreased incidence of intestinal failure–associated liver disease. The effect of lipid sparing on neurodevelopment (ND) and growth remains unknown. This study investigated the impact of SO dose on ND and growth over the first 2 years of age in preterm neonates. Materials and Methods: This is a single‐site prospective follow‐up study. Neonates with a gestational age ≤29 weeks were randomized to low‐dose (LOW) or standard‐dose (CON) SO. Bayley Scales of Infant Development III and anthropometric measurements were collected at approximately 6, 12, and 24 months corrected gestational age. Results: Subjects were premature, with a mean (±SD) gestational age of 28 ± 1 and 27 ± 1 weeks (P = .3) for LOW and CON, respectively. Thirty subjects completed follow‐up (LOW = 15, CON = 15). There were no differences for ND and growth outcomes when LOW was compared with CON, with the exception of a higher 12‐month follow‐up cognitive scaled score in the LOW group (P = .02). Conclusion: A reduced SO dose did not adversely affect ND or growth in this cohort of preterm neonates. However, larger studies are needed to determine the long‐term safety of SO dose reduction before this strategy can be adopted. 相似文献
49.
50.
Schlörmann W Hiller B Jahns F Zöger R Hennemeier I Wilhelm A Lindhauer MG Glei M 《European journal of nutrition》2012,51(7):827-839