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111.
Hyun-Shik Yun Hongkyun Lee Young-Tae Park Min-Kyu Ji Akhil N. Kabra Chung Jeon Byong-Hun Jeon Jaeyoung Choi 《Applied biochemistry and biotechnology》2014,173(8):2054-2064
Microalgae were selected and isolated from acid mine drainage in order to find microalgae species which could be cultivated in low pH condition. In the present investigation, 30 microalgae were isolated from ten locations of acid mine drainage in South Korea. Four microalgae were selected based on their growth rate, morphology, and identified as strains of KGE1, KGE3, KGE4, and KGE7. The dry biomass of microalgae species ranged between 1 and 2 g L?1 after 21 days of cultivation. The growth kinetics of microalgae was well described by logistic growth model. Among these, KGE7 has the highest biomass production (2.05?±?0.35 g L?1), lipid productivity (0.82?±?0.14 g L?1), and C16–C18 fatty acid contents (97.6 %). These results suggest that Scenedesmus sp. KGE 7 can be utilized for biodiesel production based on its high biomass and lipid productivity. 相似文献
112.
Efficient Diketopyrrolopyrrole‐Based Small‐Molecule Bulk‐Heterojunction Solar Cells with Different Electron‐Donating End‐Groups 下载免费PDF全文
Yu Jin Kim Jang Yeol Back Seul‐Ong Kim Chan‐Woo Jeon Prof. Chan Eon Park Prof. Yun‐Hi Kim 《化学:亚洲杂志》2014,9(9):2505-2513
A series of small molecules that contained identical π‐spacers (ethyne), a central diketopyrrolopyrrole (DPP) unit, and different aromatic electron‐donating end‐groups were synthesized and used in organic solar cells (OSCs) to study the effect of electron‐donating groups on the device performance. The three compounds, DPP‐A‐Ph , DPP‐A‐Na , and DPP‐A‐An , possessed intense absorption bands that covered a wide range, from 350 to 750 nm, and relatively low HOMO energy levels, from ?5.50 to ?5.55 eV. DPP‐A‐An , which contained anthracene end‐groups, demonstrated a stronger absorbance and a higher hole mobility than DPP‐A‐Ph , which contained phenyl groups, and DPP‐A‐Na , which contained naphthalene units. The power‐conversion efficiencies (PCEs) of OSCs based on organic:PC71BM blends (1:1, w/w) with a processed DIO additive were 3.93 % for DPP‐A‐An , 3.02 % for DPP‐Na , and 2.26 % for DPP‐A‐Ph . These findings suggest that a DPP core that is functionalized with electron‐donating capping groups constitutes a promising new class of solution‐processable small molecules for OSC applications. 相似文献
113.
Un Sil Jeon Jun-Pyo Choi You-Sun Kim Sung-Ho Ryu Yoon-Keun Kim 《Experimental & molecular medicine》2015,47(5):e163
Atherosclerosis is a chronic progressive inflammatory disorder and the leading cause of cardiovascular mortality. Here we assessed the dynamic changes of T-cell-derived cytokines, such as inteferon (IFN)-γ, interleukin (IL)-17 and IL-4, during the progression of atherosclerosis in apolipoprotein E-null (ApoE−/−) mice, to understand the role of immune responses in different stages of atherosclerosis. Male ApoE−/− mice were fed a high-fat, western-type diet (WD: 21% lipid, 1.5% cholesterol) after 5 weeks of age and were compared with C57BL/6 wild-type control mice fed a standard chow diet. Atherosclerotic lesions appeared in the aortic sinus of ApoE−/− mice 4 weeks after WD and the lesions progressed and occupied >50% of the total sinus area 16 weeks after WD. Aortic IL-17 mRNA and protein expression started to increase in ApoE−/− mice after 4 weeks on the WD and peaked at around 8–12 weeks on the WD. In terms of systemic expression of T-cell-derived cytokines, IL-17 production from splenocytes after anti-CD3/CD28 stimuli increased from 4 weeks on the WD, peaked at 12 weeks and returned to control levels at 16 weeks. The production of IFN-γ and IL-4 (Th1 and Th2 cytokines, respectively) from splenocytes was delayed compared with IL-17. Taken together, the present data indicate that Th17 cell response may be involved at an early stage in the development of atherosclerosis. 相似文献
114.
As a new model of chemical assay-guided natural product isolation, an effective chemodosimetric assay system was devised. Our chemical assay system features a fluorogenic chemodosimeter immobilized on a solid support, which offers advantages in identifying the desired compounds in complex natural product mixtures. To isolate only compounds with the target functional groups, the click chemistry concept was adopted. The model system presented here was developed for natural products with a terminal alkyne. Using our newly designed alkyne sensing beads with the aforementioned features, we have readily identified, quantified, and isolated compounds with a terminal alkyne group from plant extracts. 相似文献
115.
Kang Il Yoo Ji Yeong Jeon Su Jeong Ryu Giri Nam Hyewon Youn Eun Young Choi 《Experimental & molecular medicine》2015,47(2):e140
In allogeneic transplantation, including the B6 anti-BALB.B settings, H60 and H4 are two representative dominant minor histocompatibility antigens that induce strong CD8 T-cell responses. With different distribution patterns, H60 expression is restricted to hematopoietic cells, whereas H4 is ubiquitously expressed. H60-specific CD8 T-cell response has been known to be dominant in most cases of B6 anti-BALB.B allo-responses, except in the case of skin transplantation. To understand the mechanism underlying the subdominance of H60 during allogeneic skin transplantation, we investigated the dynamics of the H60-specific CD8 T cells in B6 mice transplanted with allogeneic BALB.B tail skin. Unexpectedly, longitudinal bioluminescence imaging and flow cytometric analyses revealed that H60-specific CD8 T cells were not always subdominant to H4-specific cells but instead showed a brief dominance before the H4 response became predominant. H60-specific CD8 T cells could expand in the draining lymph node and migrate to the BALB.B allografts, indicating their active participation in the anti-BALB.B allo-response. Enhancing the frequencies of H60-reactive CD8 T cells prior to skin transplantation reversed the immune hierarchy between H60 and H4. Additionally, H60 became predominant when antigen presentation was limited to the direct pathway. However, when antigen presentation was restricted to the indirect pathway, the expansion of H60-specific CD8 T cells was limited, whereas H4-specific CD8 T cells expanded significantly, suggesting that the temporary immunodominance and eventual subdominance of H60 could be due to their reliance on the direct antigen presentation pathway. These results enhance our understanding of the immunodominance phenomenon following allogeneic tissue transplantation. 相似文献
116.
Reversible Transformation between Cubane and Stairstep Cu4I4 Clusters Using Heat or Solvent Vapor 下载免费PDF全文
Seonghwa Cho Youngeun Jeon Sangjin Lee Prof. Jineun Kim Dr. Tae Ho Kim 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(4):1439-1443
The controlled self‐assembly of CuI and an asymmetric ligand with mixed N/S donors, 2‐(tert‐butylthio)‐N‐(pyridin‐3‐yl)acetamide ( L ), afforded three CuI coordination polymers (CPs), [Cu4I4 L 2(MeCN)2]n ( 1 ), [Cu4I4 L 2]n ( 2 ), and {[Cu4I4 L 2] ? MeOH}n ( 3 ). X‐ray analyses showed that CPs 1 – 3 are supramolecular isomers with 1, 2, and 3D structures, respectively. CP 1 adopts a stairstep Cu4I4 cluster, whereas CPs 2 and 3 are composed of cubane‐like Cu4I4 clusters. Crystal‐to‐crystal transformations of 1 to 2 and 3 showed reversible transformations between different Cu4I4 clusters using heat or solvent (acetonitrile or methanol) vapor. CP 2 was reversibly transformed to 3 by the addition of methanol and heat. Therefore, the transformations between supramolecular isomers 1 , 2 , and 3 are completely reversible. 相似文献
117.
Daewha Hong KiEun Bae Dr. Duckshin Park Houngkyung Kim Seok‐Pyo Hong Mi‐Hee Kim Dr. Bong Soo Lee Dr. Sangwon Ko Prof. Dr. Seokwoo Jeon Xu Zheng Prof. Dr. Wan Soo Yun Prof. Dr. Yang‐Gyun Kim Prof. Dr. Insung S. Choi Prof. Dr. Jungkyu K. Lee 《化学:亚洲杂志》2015,10(3):568-571
Direct patterning of streptavidin and NIH 3T3 fibroblast cells was successfully achieved over a large‐area pristine graphene sheet on Si/SiO2 by aryl azide‐based photografting with the conventional UV lithographic technique and surface‐initiated, atom transfer radical polymerization of oligo(ethylene glycol) methacrylate. 相似文献
118.
Sungmi Park Jeong-Kook Kim Chang Joo Oh Seung Hee Choi Jae-Han Jeon In-Kyu Lee 《Experimental & molecular medicine》2015,47(3):e145
Scoparone, which is a major constituent of Artemisia capillaries, has been identified as an anticoagulant, hypolipidemic, vasorelaxant, anti-oxidant and anti-inflammatory drug, and it is used for the traditional treatment of neonatal jaundice. Therefore, we hypothesized that scoparone could suppress the proliferation of VSMCs by interfering with STAT3 signaling. We found that the proliferation of these cells was significantly attenuated by scoparone in a dose-dependent manner. Scoparone markedly reduced the serum-stimulated accumulation of cells in the S phase and concomitantly increased the proportion of cells in the G0/G1 phase, which was consistent with the reduced expression of cyclin D1, phosphorylated Rb and survivin in the VSMCs. Cell adhesion markers, such as MCP-1 and ICAM-1, were significantly reduced by scoparone. Interestingly, this compound attenuated the increase in cyclin D promoter activity by inhibiting the activities of both the WT and active forms of STAT3. Similarly, the expression of a cell proliferation marker induced by PDGF was decreased by scoparone with no change in the phosphorylation of JAK2 or Src. On the basis of the immunofluorescence staining results, STAT3 proteins phosphorylated by PDGF were predominantly localized to the nucleus and were markedly reduced in the scoparone-treated cells. In summary, scoparone blocks the accumulation of STAT3 transported from the cytosol to the nucleus, leading to the suppression of VSMC proliferation through G1 phase arrest and the inhibition of Rb phosphorylation. This activity occurs independent of the form of STAT3 and upstream of kinases, such as Jak and Src, which are correlated with abnormal vascular remodeling due to the presence of an excess of growth factors following vascular injury. These data provide convincing evidence that scoparone may be a new preventative agent for the treatment of cardiovascular diseases. 相似文献
119.
Won-Hee Lee Hyun-Il Choi Sung-Wook Hong Kwang-sun Kim Yong Song Gho Seong Gyu Jeon 《Experimental & molecular medicine》2015,47(9):e183
The emergence of multidrug-resistant Klebsiella pneumoniae highlights the need to develop preventive measures to ameliorate Klebsiella infections. Bacteria-derived extracellular vesicles (EVs) are spherical nanometer-sized proteolipids enriched with outer membrane proteins. Gram-negative bacteria-derived EVs have gained interest for use as nonliving complex vaccines. In the present study, we evaluated whether K. pneumoniae-derived EVs confer protection against bacteria-induced lethality. K. pneumoniae-derived EVs isolated from in vitro bacterial culture supernatants induced innate immunity, including the upregulation of co-stimulatory molecule expression and proinflammatory mediator production. EV vaccination via the intraperitoneal route elicited EV-reactive antibodies and interferon-gamma-producing T-cell responses. Three vaccinations with the EVs prevented bacteria-induced lethality. As verified by sera and splenocytes adoptive transfer, the protective effect of EV vaccination was dependent on both humoral and cellular immunity. Taken together, these findings suggest that K. pneumoniae-derived EVs are a novel vaccine candidate against K. pneumoniae infections. 相似文献
120.