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351.
Jesper Lau Erik B. Pedersen Jesper Wengel 《Nucleosides, nucleotides & nucleic acids》2013,32(5-6):961-965
Abstract As amino sugars1 and aminonucleosides2 show remarkable anticancer and antiviral properties the synthetic and biological investigation in this field has become challenging. 相似文献
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Benjamin Lau Jingdong Cheng Dirk Flemming Giuseppe La Venuta Otto Berninghausen Roland Beckmann Ed Hurt 《Molecular cell》2021,81(2):293-303.e4
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354.
355.
N Bhardwaj U Santhanam L L Lau S B Tatter J Ghrayeb M Rivelis R M Steinman P B Sehgal L T May 《Journal of immunology (Baltimore, Md. : 1950)》1989,143(7):2153-2159
We have looked for IL-6, a cytokine that has immunomodulating and inflammation-associated activities, in joint exudates (fluid and mononuclear cells) from patients with rheumatoid arthritis and other arthritides using both biologic and biochemical assays. IL-6 was assessed by its ability to stimulate alpha 1-antichymotrypsin secretion from the human hepatoma cell line Hep3B clone 2, an activity which is blocked by an antiserum to Escherichia coli derived IL-6, and by the growth of the IL-6-dependent murine hybridoma 7TD1 cell line. IL-6 isoforms in synovial fluid were characterized by immunoaffinity chromatography followed by Western blotting. The presence of IL-1 in synovial fluids and its production by synovial fluid mononuclear cells was monitored by Western blotting and indirect immunofluorescence with polyclonal anti-IL-1 beta antisera. In an analysis of 30 effusions from 27 rheumatoid patients with acutely inflamed joints, abundant quantities of IL-6 (greater than 2 ng/ml) were detected in 23 by the alpha 1-antichymotrypsin bioassay. Several rheumatoid synovial fluids also had elevated IL-6 levels in the 7TD1 bioassay. Seven of nine nonrheumatoid effusions also contained high levels of IL-6 (greater than 2 ng/ml). No IL-1 (less than 0.25 ng/ml) could be detected by Western blotting in 10 rheumatoid effusions even though eight of these contained high levels of IL-6. The IL-6 activity could be neutralized with a rabbit antiserum to rIL-6. Multiple IL-6 isoforms (25, 30, 45 kDa) were present in two rheumatoid and one traumatic effusion studied. Fresh mononuclear cells isolated from various synovial effusions did not appear to make IL-6 constitutively, as no IL-6 could be detected in the media of cells cultured for 12 to 18 h after isolation. Similarly, there was no constitutive production of IL-1 by these cells. However, synovial fluid mononuclear cells could be induced to secrete both IL-6 and IL-1 after stimulation with LPS. The LPS-responsive cells were monocytes and not lymphocytes or dendritic cells. These findings suggest that IL-6 is involved in inflammatory joint disease. However, the primary cells synthesizing it may be located in the synovial lining instead of the joint exudate. 相似文献
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M. Shurrab A. Kaoutskaia A. Baranchuk C. Lau T. Singarajah I. Lashevsky D. Newman J. S. Healey E. Crystal 《Netherlands heart journal》2018,26(5):233-239
Background
The use of magnetic resonance imaging (MRI)-conditional permanent pacemakers has increased significantly. In this meta-analysis, we examine the safety of MRI-conditional pacing systems in comparison with conventional systems.Methods
An electronic search was performed using major databases, including studies that compared the outcomes of interest between patients receiving MRI-conditional pacemakers (MRI group) versus conventional pacemakers (control group).Results
Six studies (5 retrospective and 1 prospective non-randomised) involving 2,118 adult patients were identified. The MRI-conditional pacemakers, deployed in 969 patients, were all from a single manufacturer (Medtronic Pacing System with 5086 leads). The rate of pacemaker lead dislodgement (atrial and ventricular) was significantly higher in the MRI group (3% vs. 1%, OR 2.47 (95% CI 1.26; 4.83), p?=?0.008). The MRI group had a significantly higher rate of pericardial complications (2% vs. 1%, OR 4.23 (95% CI 1.18; 15.10), p?=?0.03) and a numerically higher overall complication rate in comparison with the conventional group (6% vs. 3%, OR 2.02 (95% CI 0.88; 4.66), p?=?0.10) but this was not statistically significant.Conclusions
In this meta-analysis, the rates of pacemaker lead dislodgement and pericardial complications were significantly higher with the Medtronic MRI-conditional pacing system.358.
359.
Julie Rousseau Zhengxing Zhang Xiaozhu Wang Chengcheng Zhang Joseph Lau Etienne Rousseau Milena Čolović Navjit Hundal-Jabal François Bénard Kuo-Shyan Lin 《Bioorganic & medicinal chemistry letters》2018,28(5):899-905
Two novel bifunctional tetrahydroxamate chelators 3 and 4 were synthesized and evaluated for labeling antibodies with 89Zr for positron emission tomography imaging. Compared to previously reported tetrahydroxamate chelators 1 and 2 with an iminodiacetamide backbone, 3 and 4 were based on an extended iminodipropionamide and dipropylenetriamine backbone, respectively. Trastuzumab conjugates of 3 and 4 were efficiently labeled with 89Zr (>95% radiochemical yield). The in vitro plasma stability of 89Zr-4-Trastuzumab and especially 89Zr-3-Trastuzumab was greatly improved over previously reported 89Zr-1-Trastuzumab and 89Zr-2-Trastuzumab, but their demetalation remained higher and faster than 89Zr-deferoxamine (DFO)-Trastuzumab. These observations were confirmed by PET imaging and biodistribution in mice, with significant higher bone uptake for 89Zr-4-Trastuzumab, followed by 89Zr-3-Trastuzumab, and to a lesser extent for 89Zr-DFO-Trastuzumab. Molecular modeling showed that 3 and 4 with an extended backbone could form eight-coordinate Zr-complexes as compared to only seven-coordinate Zr-complexes of 1 and 2. Our data suggest further elongation of linker length between hydroxamate motifs of this class of chelators is needed to reach a better Zr-coordination configuration and improve in vivo stability. 相似文献
360.
Fused‐Ring Electron Acceptor ITIC‐Th: A Novel Stabilizer for Halide Perovskite Precursor Solution
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Minchao Qin Jie Cao Tiankai Zhang Jiangquan Mai Tsz‐Ki Lau Shu Zhou Yang Zhou Jiayu Wang Yao‐Jane Hsu Ni Zhao Jianbin Xu Xiaowei Zhan Xinhui Lu 《Liver Transplantation》2018,8(18)
Solution‐processed perovskite solar cells have great potential for low‐cost roll‐to‐roll fabrication. However, the degradation of aged precursor solutions will become a critical obstacle to mass production. In this report, a small molecule (ITIC‐Th) is employed to stabilize the perovskite precursor solution containing mixed cations and halides. It is found that ITIC‐Th can effectively suppress the formation of yellow δ‐phase in the films made from aged precursor solutions. Consequently, the devices fabricated from the aged precursor solution with ITIC‐Th experience much less efficiency drop with the increase of the precursor aging time—from 19.20% (fresh) to 16.55% (39 d), compared with the devices made from conventional precursor solutions dropping from 18.07% (fresh) to 1.76% (39 d). The characterizations suggest that ITIC‐Th is beneficial for CH3NH3+ cations to be incorporated into the crystal structure, facilitating the formation of perovskite phase. Furthermore, the presence of ITIC‐Th in the perovskite thin film gives rise to additional photocurrent as well as improved fill factor due to the well‐matched energy levels, the passivation of defects, and the complementary absorption spectra, suggesting a new route toward future high‐efficiency solar cells—incorporating organic non‐fullerene acceptors and halide perovskite materials into the same active layer. 相似文献