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排序方式: 共有818条查询结果,搜索用时 31 毫秒
31.
Li Ding Maciej Paszkowski-Rogacz Anja Nitzsche Mikolaj Michal Slabicki Anne-Kristin Heninger Ingrid de Vries Ralf Kittler Magno Junqueira Andrej Shevchenko Herbert Schulz Norbert Hubner Michael Xavier Doss Agapios Sachinidis Juergen Hescheler Roberto Iacone Konstantinos Anastassiadis A. Francis Stewart M. Teresa Pisabarro Antonio Caldarelli Ina Poser Frank Buchholz 《Cell Stem Cell》2009,4(5):403-415
32.
33.
Renaud Beaudegnies Andrew J.F. Edmunds Torquil E.M. Fraser Roger G. Hall Timothy R. Hawkes Glynn Mitchell Juergen Schaetzer Sebastian Wendeborn Jane Wibley 《Bioorganic & medicinal chemistry》2009,17(12):4134-4152
A review, outlining the origins and subsequent development of the triketone class of herbicidal 4-hydroxyphenylpyruvate dioxygenase (HPPD) inhibitors. 相似文献
34.
Carina Loffredo Nilson A. Assunção Juergen Gerhardt M. Terêsa Machini Miranda 《Journal of peptide science》2009,15(12):808-817
Several conditions have been used in the coupling reaction of stepwise SPPS at elevated temperature (SPPS‐ET), but we have elected the following as our first choice: 2.5‐fold molar excess of 0.04–0.08 M Boc or Fmoc‐amino acid derivative, equimolar amount of DIC/HOBt (1:1) or TBTU/DIPEA (1:3), 25% DMSO/toluene, 60 °C, conventional heating. In this study, aimed to further examine enantiomerization under such condition and study the applicability of our protocols to microwave‐SPPS, peptides containing L ‐Ser, L ‐His, L ‐Cys and/or L ‐Met were manually synthesized traditionally, at 60 °C using conventional heating and at 60 °C using microwave heating. Detailed assessment of all crude peptides (in their intact and/or fully hydrolyzed forms) revealed that, except for the microwave‐assisted coupling of L ‐Cys, all other reactions occurred with low levels of amino acid enantiomerization (<2%). Therefore, herein we (i) provide new evidences that our protocols for SPPS at 60 °C using conventional heating are suitable for routine use, (ii) demonstrate their appropriateness for microwave‐assisted SPPS by Boc and Fmoc chemistries, (iii) disclose advantages and limitations of the three synthetic approaches employed. Thus, this study complements our past research on SPPS‐ET and suggests alternative conditions for microwave‐assisted SPPS. Copyright © 2009 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
35.
Florian Streitner Juergen Kuschyk Christian Veltmann Desiree Ratay Nina Schoene Ines Streitner Martina Brueckmann Burghard Schumacher Martin Borggrefe Christian Wolpert 《Cytokine》2009,47(3):166-172
BackgroundSeveral studies have attempted to identify risk factors for the development of an electrical storm (ES), which is defined as ⩾3 separate ventricular tachyarrhythmic (VT/VF) events, but in the majority of studies no triggers have been found. However, little is known about the role of inflammation and NT-proBNP in patients with ES. The aim of this study was therefore to assess the relationship of Interleukin-6 (IL-6), high-sensitivity C-reactive protein (hs-CRP) and NT-proBNP serum concentrations in ICD-patients with or without single spontaneous ventricular tachyarrhythmic events (VT/VF) and in ES.MethodsMarkers were determined in 51 patients without ICD-intervention, in 15 ICD-patients with single VT/VF-episodes during 9-months follow-up and in 20 ICD-patients with ES (blood sampling performed within 60 min after fulfilling ES criteria). VT/VF-episodes were analysed by stored ICD-electrograms.ResultsAll patients had idiopathic dilated cardiomyopathy (n = 23) or coronary artery disease (n = 63). Patients with ES revealed significantly higher mean serum concentrations of all markers (IL-6 15.19 ± 10.34 pg/mL, hs-CRP 20.12 ± 14.4 mg/L, NT-proBNP 4799 ± 4596 pg/mL) compared to baseline values of patients with single VT/VF-events during follow-up (IL-6 8.37 ± 5.8 pg/mL (p = 0.03), hs-CRP 4.7 ± 5.3 mg/dL (p < 0.001), NT-proBNP 1913 ± 2665 pg/mL (p = 0.04)) and compared to baseline values of ICD-patients without device intervention (IL-6 4.62 ± 3.66 pg/mL (p < 0.001), hs-CRP 4.1 ± 3.4 mg/L (p < 0.001), NT-proBNP 1461 ± 2281 pg/mL (p < 0.001)). In 9/20 patients presenting with ES (45%) baseline values were available. All markers were significantly higher during ES compared to event-free determination (IL-6 14.54 ± 10.43 vs. 7.03 ± 2.83 pg/mL (p = 0.04), hs-CRP 19.07 ± 16.07 vs. 6.5 ± 3.9 mg/L (p = 0.02), NT-proBNP 4218 ± 2561 vs. 2099 ± 1279 pg/mL (p = 0.03)).ConclusionsElectrical storm is associated with significantly elevated IL-6, hs-CRP and NT-proBNP serum concentrations in ICD-patients with structural heart disease. Thus, ES may be triggered by proinflammatory activity. Combined intraindividual elevation of determined markers might help to identify patients at risk of impending electrical storm. 相似文献
36.
An update on carotenoid biosynthesis in algae: phylogenetic evidence for the existence of two classes of phytoene synthase 总被引:3,自引:0,他引:3
Carotenoids play crucial roles in structure and function of the photosynthetic apparatus of bacteria, algae, and higher plants.
The entry-step reaction to carotenoid biosynthesis is catalyzed by the phytoene synthase (PSY), which is structurally and
functionally related in all organisms. A comparative genomic analysis regarding the PSY revealed that the green algae Ostreococcus and Micromonas possess two orthologous copies of the PSY genes, indicating an ancient gene duplication event that produced two classes of
PSY in algae. However, some other green algae (Chlamydomonas reinhardtii, Chlorella vulgaris, and Volvox carteri), red algae (Cyanidioschyzon merolae), diatoms (Thalassiosira pseudonana and Phaeodactylum tricornutum), and higher plants retained only one class of the PSY gene whereas the other gene copy was lost in these species. Further,
similar to the situation in higher plants recent gene duplications of PSY have occurred for example in the green alga Dunaliella salina/bardawil. As members of the PSY gene families in some higher plants are differentially regulated during development or stress, the
discovery of two classes of PSY gene families in some algae suggests that carotenoid biosynthesis in these algae is differentially
regulated in response to development and environmental stress as well. 相似文献
37.
Immunogenicity of HLA-A1-restricted peptides derived from S100A4 (metastasin 1) in melanoma patients
Valeska Hofmeister-Mueller Claudia S. Vetter-Kauczok Ramona Ullrich Katharina Meder Eugene Lukanidin Eva-Bettina Broecker Per thor Straten Mads Hald Andersen David Schrama Juergen C. Becker 《Cancer immunology, immunotherapy : CII》2009,58(8):1265-1273
S100A4 (metastasin 1) belongs to the S100 family of Ca2+ binding proteins. While not present in most differentiated adult tissues, S100A4 is upregulated in the micromilieu of tumors.
It is primarily expressed by tumor-associated macrophages, fibroblasts, and tumor endothelial cells. Due to its strong induction
in tumors S100A4 is a promising target for cancer immunotherapy. By reverse immunology, using epitope prediction programs,
we identified 3 HLA-A1-restricted peptide epitopes (S100A4 A1-1, A1-2, and A1-3) which are subject to human T cell responses
as detected in peripheral blood of melanoma patients by means of IFN-γ ELISPOT and cytotoxicity assays. In addition, IFN-γ
responses to S100A4 A1-2 can not only be induced by stimulation of T cells with peptide-loaded DC but also by stimulation
with S100A4 protein-loaded DC, indicating that this epitope is indeed generated by processing of the endogenously expressed
protein. In addition, S100A4 A1-2 reactive T cells demonstrate lysis of HLA-A1+ fibroblasts in comparison to HLA-A1− fibroblasts. In summary, this HLA-A1-restricted peptide epitope is a candidate for immunotherapeutical approaches targeting
S100A4-expressing cells in the tumor stroma. 相似文献
38.
Regulation of nitric oxide (NO) production by plant nitrate reductase in vivo and in vitro. 总被引:41,自引:0,他引:41
Peter Rockel Frank Strube Andra Rockel Juergen Wildt Werner M Kaiser 《Journal of experimental botany》2002,53(366):103-110
NO (nitric oxide) production from sunflower plants (Helianthus annuus L.), detached spinach leaves (Spinacia oleracea L.), desalted spinach leaf extracts or commercial maize (Zea mays L.) leaf nitrate reductase (NR, EC 1.6.6.1) was continuously followed as NO emission into the gas phase by chemiluminescence detection, and its response to post-translational NR modulation was examined in vitro and in vivo. NR (purified or in crude extracts) in vitro produced NO at saturating NADH and nitrite concentrations at about 1% of its nitrate reduction capacity. The K(m) for nitrite was relatively high (100 microM) compared to nitrite concentrations in illuminated leaves (10 microM). NO production was competitively inhibited by physiological nitrate concentrations (K(i)=50 microM). Importantly, inactivation of NR in crude extracts by protein phosphorylation with MgATP in the presence of a protein phosphatase inhibitor also inhibited NO production. Nitrate-fertilized plants or leaves emitted NO into purified air. The NO emission was lower in the dark than in the light, but was generally only a small fraction of the total NR activity in the tissue (about 0.01-0.1%). In order to check for a modulation of NO production in vivo, NR was artificially activated by treatments such as anoxia, feeding uncouplers or AICAR (a cell permeant 5'-AMP analogue). Under all these conditions, leaves were accumulating nitrite to concentrations exceeding those in normal illuminated leaves up to 100-fold, and NO production was drastically increased especially in the dark. NO production by leaf extracts or intact leaves was unaffected by nitric oxide synthase inhibitors. It is concluded that in non-elicited leaves NO is produced in variable quantities by NR depending on the total NR activity, the NR activation state and the cytosolic nitrite and nitrate concentration. 相似文献
39.
Volker Lennerz Stefanie Gross Elisa Gallerani Cristiana Sessa Nicolas Mach Steffen Boehm Dagmar Hess Lotta von Boehmer Alexander Knuth Adrian F. Ochsenbein Ulrike Gnad-Vogt Juergen Zieschang Ulf Forssmann Thomas Woelfel Eckhart Kaempgen 《Cancer immunology, immunotherapy : CII》2014,63(4):381-394
Purpose
Survivin is a member of the inhibitor-of-apoptosis family. Essential for tumor cell survival and overexpressed in most cancers, survivin is a promising target for anti-cancer immunotherapy. Immunogenicity has been demonstrated in multiple cancers. Nonetheless, few clinical trials have demonstrated survivin-vaccine-induced immune responses.Experimental design
This phase I trial was conducted to test whether vaccine EMD640744, a cocktail of five HLA class I-binding survivin peptides in Montanide® ISA 51 VG, promotes anti-survivin T-cell responses in patients with solid cancers. The primary objective was to compare immunologic efficacy of EMD640744 at doses of 30, 100, and 300 μg. Secondary objectives included safety, tolerability, and clinical efficacy.Results
In total, 49 patients who received ≥2 EMD640744 injections with available baseline- and ≥1 post-vaccination samples [immunologic-diagnostic (ID)-intention-to-treat] were analyzed by ELISpot- and peptide/MHC-multimer staining, revealing vaccine-activated peptide-specific T-cell responses in 31 patients (63 %). This cohort included the per study protocol relevant ID population for the primary objective, i.e., T-cell responses by ELISpot in 17 weeks following first vaccination, as well as subjects who discontinued the study before week 17 but showed responses to the treatment. No dose-dependent effects were observed. In the majority of patients (61 %), anti-survivin responses were detected only after vaccination, providing evidence for de novo induction. Best overall tumor response was stable disease (28 %). EMD640744 was well tolerated; local injection-site reactions constituted the most frequent adverse event.Conclusions
Vaccination with EMD640744 elicited T-cell responses against survivin peptides in the majority of patients, demonstrating the immunologic efficacy of EMD640744. 相似文献40.