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121.
Wang Y Kang G Liu J Zhao M Wu J Zhang X Li Y Zhong X Yang Y Peng S 《Metallomics : integrated biometal science》2012,4(5):441-447
To discover whether novel anti-tumor platinum agents are capable of selectively accumulating in tumor tissue, three novel potassium N-[(2S,3R,4R,5R)-2,3,4,5,6-pentahydroxylhex-1-yl]-L-amino acid dichloroplatinates(II) were prepared. At a dose of 1.67 μmol kg(-1) the in vivo anti-tumor potencies of two of the compounds were higher than that of oxaliplatin. The mortality analysis indicated that these compounds resulted in a 100% survival rate, whereas oxaliplatin lead to an 80% survival rate. The organ damage examination indicated that these compounds induced less damage than oxaliplatin. The platinum accumulation in the organs, blood and bone was significantly lower than that of oxaliplatin treated mice, while the platinum accumulation in the tumor tissue was significantly higher than that of the oxaliplatin treated mice. 相似文献
122.
Min Ki Jee Ji Hoon Kim Yong Man Han Sung Jun Jung Kyung Sun Kang Dong Wook Kim Soo Kyung Kang 《PloS one》2010,5(2)
Background and Methods
In this study, we utilized a combination of low oxygen tension and a novel anti-oxidant, 4-(3,4-dihydroxy-phenyl)-derivative (DHP-d) to directly induce adipose tissue stromal cells (ATSC) to de-differentiate into more primitive stem cells. De-differentiated ATSCs was overexpress stemness genes, Rex-1, Oct-4, Sox-2, and Nanog. Additionally, demethylation of the regulatory regions of Rex-1, stemnesses, and HIF1α and scavenging of reactive oxygen species were finally resulted in an improved stem cell behavior of de-differentiate ATSC (de-ATSC). Proliferation activity of ATSCs after dedifferentiation was induced by REX1, Oct4, and JAK/STAT3 directly or indirectly. De-ATSCs showed increased migration activity that mediated by P38/JUNK and ERK phosphorylation. Moreover, regenerative efficacy of de-ATSC engrafted spinal cord-injured rats and chemical-induced diabetes animals were significantly restored their functions.Conclusions/Significance
Our stem cell remodeling system may provide a good model which would provide insight into the molecular mechanisms underlying ATSC proliferation and transdifferentiation. Also, these multipotent stem cells can be harvested may provide us with a valuable reservoir of primitive and autologous stem cells for use in a broad spectrum of regenerative cell-based disease therapy. 相似文献123.
Plants,microorganisms, and soil temperatures contribute to a decrease in methane fluxes on a drained Arctic floodplain 下载免费PDF全文
Min Jung Kwon Felix Beulig Iulia Ilie Marcus Wildner Kirsten Küsel Lutz Merbold Miguel D. Mahecha Nikita Zimov Sergey A. Zimov Martin Heimann Edward A. G. Schuur Joel E. Kostka Olaf Kolle Ines Hilke Mathias Göckede 《Global Change Biology》2017,23(6):2396-2412
As surface temperatures are expected to rise in the future, ice‐rich permafrost may thaw, altering soil topography and hydrology and creating a mosaic of wet and dry soil surfaces in the Arctic. Arctic wetlands are large sources of CH4, and investigating effects of soil hydrology on CH4 fluxes is of great importance for predicting ecosystem feedback in response to climate change. In this study, we investigate how a decade‐long drying manipulation on an Arctic floodplain influences CH4‐associated microorganisms, soil thermal regimes, and plant communities. Moreover, we examine how these drainage‐induced changes may then modify CH4 fluxes in the growing and nongrowing seasons. This study shows that drainage substantially lowered the abundance of methanogens along with methanotrophic bacteria, which may have reduced CH4 cycling. Soil temperatures of the drained areas were lower in deep, anoxic soil layers (below 30 cm), but higher in oxic topsoil layers (0–15 cm) compared to the control wet areas. This pattern of soil temperatures may have reduced the rates of methanogenesis while elevating those of CH4 oxidation, thereby decreasing net CH4 fluxes. The abundance of Eriophorum angustifolium, an aerenchymatous plant species, diminished significantly in the drained areas. Due to this decrease, a higher fraction of CH4 was alternatively emitted to the atmosphere by diffusion, possibly increasing the potential for CH4 oxidation and leading to a decrease in net CH4 fluxes compared to a control site. Drainage lowered CH4 fluxes by a factor of 20 during the growing season, with postdrainage changes in microbial communities, soil temperatures, and plant communities also contributing to this reduction. In contrast, we observed CH4 emissions increased by 10% in the drained areas during the nongrowing season, although this difference was insignificant given the small magnitudes of fluxes. This study showed that long‐term drainage considerably reduced CH4 fluxes through modified ecosystem properties. 相似文献
124.
Stretchable Lithium‐Ion Batteries Enabled by Device‐Scaled Wavy Structure and Elastic‐Sticky Separator 下载免费PDF全文
Wei Liu Jun Chen Zheng Chen Kai Liu Guangmin Zhou Yongming Sun Min‐Sang Song Zhenan Bao Yi Cui 《Liver Transplantation》2017,7(21)
Fast developments and substantial achievements have been shaping the field of wearable electronic devices, resulting in the persistent requirement for stretchable lithium‐ion batteries (LIBs). Despite recent progress in stretchable electrodes, stretching full batteries, including electrodes, separator, and sealing material, remains a great challenge. Here, a simple design concept for stretchable LIBs via a wavy structure at the full battery device scale is reported. All components including the package are capable of being reversibly stretched by folding the entire pouch cell into a wavy shape with polydimethylsiloxane filled in each valley region. In addition, the stretchable, sticky, and porous polyurethane/poly(vinylidene fluoride) membrane is adopted as a separator for the first time, which can maintain intimate contact between electrodes and separator to continuously secure ion pathway under dynamic state. Commercial cathode, anode, and package can be utilized in this rationally designed wavy battery to enable stretchability. The results indicate good electrochemical performances and long‐term stability at repeatable release–stretch cycles. A high areal capacity of 3.6 mA h cm?2 and energy density of up to 172 W h L?1 can be achieved for the wavy battery. The promising results of the cost‐effective wavy battery with high stretchability shed light on the development of stretchable energy storages. 相似文献
125.
Tomoko Okada Yuji Yamamoto Tsubasa Shibuya Hyen-Wook Kang Hirotaka Miyachi Isao Karube Hiroshi Muramatsu Jong Min Kim 《Biochemical Engineering Journal》2008,41(1):17-23
We have developed a new method for evaluating the affinity interactions between two different proteins by applying an alternating current (AC) voltage to a micro-flow channel. An AC voltage was applied to the protein-modified microspheres in the micro-flow channel, which resulted in the oscillation of the microspheres owing to their surface charges. The oscillation amplitude showed a linear relationship with the charge density of the microspheres. As an example for protein affinity measurement, the amplitude changes of a profilin-modified microsphere were measured by the addition of actin. In the same electrical condition, the oscillation amplitude of the profilin-modified microsphere increased by ≈175% by binding with actin. Similar results in the principle were obtained for the affinity interaction between biotin and streptavidin. The results showed that the higher the charge density of the microspheres induced by binding with different proteins, the higher the oscillation amplitude of the microspheres, thus, suggesting a possible application of the micro-flow channel and AC voltage on the protein property study, as well as on the biosensor application using the oscillation amplitude changes. 相似文献
126.
Makino N Toyofuku T Takegahara N Takamatsu H Okuno T Nakagawa Y Kang S Nojima S Hori M Kikutani H Kumanogoh A 《FEBS letters》2008,582(28):3935-3940
Dilated cardiomyopathy often results from autoimmunity triggered by microbial infections during myocarditis. However, it remains unclear how immunological disorders are implicated in pathogenesis of autoimmune myocarditis. Here, we demonstrated that Sema4A, a class IV semaphorin, plays key roles in experimental autoimmune myocarditis (EAM). Dendritic cells pulsed with myosin heavy chain-α peptides induced severe myocarditis in wild-type mice, but not in Sema4A-deficient mice. In adoptive transfer experiments, CD4+ T-cells from wild-type mice induced severe myocarditis, while CD4+ T-cells from Sema4A-deficient mice exhibited considerably attenuated myocarditis. Our results indicated that Sema4A is critically involved in EAM by regulating differentiation of T-cells. 相似文献
127.
128.
Hai-Long Wang Tie-E Zhang Li-Tian Yin Min Pang Li Guan Hong-Li Liu Jian-Hong Zhang Xiao-Li Meng Ji-Zhong Bai Guo-Ping Zheng Guo-Rong Yin 《PloS one》2014,9(9)
Toxoplasma gondii (T. gondii) is an obligate intracellular protozoan parasite that infects a variety of mammals, including humans. An effective vaccine for this parasite is therefore needed. In this study, RH strain T. gondii rhoptry protein 17 was expressed in bacteria as a fusion with glutathione S-transferase (GST) and the recombinant proteins (rTgROP17) were purified via GST-affinity chromatography. BALB/c mice were nasally immunised with rTgROP17, and induction of immune responses and protection against chronic and lethal T. gondii infections were investigated. The results revealed that mice immunised with rTgROP17 produced high levels of specific anti-rTgROP17 IgGs and a mixed IgG1/IgG2a response of IgG2a predominance. The systemic immune response was associated with increased production of Th1 (IFN-γand IL-2) and Th2 (IL-4) cytokines, and enhanced lymphoproliferation (stimulation index, SI) in the mice immunised with rTgROP17. Strong mucosal immune responses with increased secretion of TgROP17-specific secretory IgA (SIgA) in nasal, vaginal and intestinal washes were also observed in these mice. The vaccinated mice displayed apparent protection against chronic RH strain infection as evidenced by their lower liver and brain parasite burdens (59.17% and 49.08%, respectively) than those of the controls. The vaccinated mice also exhibited significant protection against lethal infection of the virulent RH strain (survival increased by 50%) compared to the controls. Our data demonstrate that rTgROP17 can trigger strong systemic and mucosal immune responses against T. gondii and that ROP17 is a promising candidate vaccine for toxoplasmosis. 相似文献
129.
Yunyi Kang Andrew Hodges Edison Ong William Roberts Carlo Piermarocchi Giovanni Paternostro 《PloS one》2014,9(7)
The BCR-ABL translocation is found in chronic myeloid leukemia (CML) and in Ph+ acute lymphoblastic leukemia (ALL) patients. Although imatinib and its analogues have been used as front-line therapy to target this mutation and control the disease for over a decade, resistance to the therapy is still observed and most patients are not cured but need to continue the therapy indefinitely. It is therefore of great importance to find new therapies, possibly as drug combinations, which can overcome drug resistance. In this study, we identified eleven candidate anti-leukemic drugs that might be combined with imatinib, using three approaches: a kinase inhibitor library screen, a gene expression correlation analysis, and literature analysis. We then used an experimental search algorithm to efficiently explore the large space of possible drug and dose combinations and identified drug combinations that selectively kill a BCR-ABL+ leukemic cell line (K562) over a normal fibroblast cell line (IMR-90). Only six iterations of the algorithm were needed to identify very selective drug combinations. The efficacy of the top forty-nine combinations was further confirmed using Ph+ and Ph- ALL patient cells, including imatinib-resistant cells. Collectively, the drug combinations and methods we describe might be a first step towards more effective interventions for leukemia patients, especially those with the BCR-ABL translocation. 相似文献
130.