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991.
Restricting the Solubility of Polysulfides in Li‐S Batteries Via Electrolyte Salt Selection 下载免费PDF全文
992.
NAD(P)H:quinone oxidoreductase (NQO1), an obligatory two-electron reductase, is a
ubiquitous cytosolic enzyme that catalyzes the reduction of quinone substrates.
The NQO1- mediated two-electron reduction of quinones can be either
chemoprotection/detoxification or a chemotherapeutic response, depending on the
target quinones. When toxic quinones are reduced by NQO1, they are conjugated
with glutathione or glucuronic acid and excreted from the cells. Based on this
protective effect of NQO1, the use of dietary compounds to induce the expression
of NQO1 has emerged as a promising strategy for cancer prevention. On the other
hand, NQO1-mediated two-electron reduction converts certain quinone compounds
(such as mitomycin C, E09, RH1 and β-lapachone) to cytotoxic agents,
leading to cell death. It has been known that NQO1 is expressed at high levels
in numerous human cancers, including breast, colon, cervix, lung, and pancreas,
as compared with normal tissues. This implies that tumors can be preferentially
damaged relative to normal tissue by cytotoxic quinone drugs. Importantly, NQO1
has been shown to stabilize many proteins, including p53 and p33ING1b, by
inhibiting their proteasomal degradation. This review will summarize the
biological roles of NQO1 in cancer, with emphasis on recent findings and the
potential of NQO1 as a therapeutic target for the cancer therapy. [BMB Reports
2015; 48(11): 609-617] 相似文献
993.
Doreen K. S. Goh Roberto Bacilieri Gilles Chaix Olivier Monteuuis 《Tree Genetics & Genomes》2013,9(5):1329-1341
Sixteen families derived from a clonal seed orchard (CSO) and 10 “provenances” (Prov) of teak (Tectona grandis) were tested in two different sites to be compared with respect to their growth performances. Both sites were located in Sabah, East Malaysia, under 2,500 mm of annual rainfall and no distinct dry season. The land in Taliwas was flat but prone to waterlogging. In Luasong, the soil was more hilly, acidic, and less fertile, though deeper. Nearly 9 years after planting, the two classes of genetic entries showed significant differences for height (P?=?0.0002) and diameter at breast height (DBH) and volume (P?<?0.0001) for the two sites combined. The superiority of the CSO families compared with the Prov class was more obvious in Luasong with averages of 18.0 vs 15.2 m (+18.6 %) for height, 18.1 vs 15.1 cm (+20.2 %) for DBH, and 0.179 vs 0.107 m3 for individual tree volume (+67.9 %), as against 17.4 vs 15.7 m (+11.2 %), 19.1 vs 16.8 cm (+13.5 %), and 0.176 vs 0.126 m3 (+40.3 %), respectively, in Taliwas. The CSO families were also more prone to site interaction for height (P?=?0.004) and, to a lesser extent, for volume (P?=?0.017) than the “Prov” (P?=?0.030 and P?=?0.057, respectively). Narrow-sense heritabilities estimated for the 16 CSO families across the two sites were lower for DBH (0.17) and volume (0.23) than for height (0.38). Type B genetic correlations suggested also higher site × families interactions for height (r B?=?0.28). 相似文献
994.
Huikyoung Chang Hyunjung Choi Kyung‐Mi Joo Tae Ryong Lee 《Pigment cell & melanoma research》2012,25(6):765-772
Human skin hyperpigmentation disorders occur when the synthesis and/or distribution of melanin increases. The distribution of melanin in the skin is achieved by melanosome transport and transfer. The transport of melanosomes, the organelles where melanin is made, in a melanocyte precedes the transfer of the melanosomes to a keratinocyte. Therefore, hyperpigmentation can be regulated by decreasing melanosome transport. In this study, we found that an extract of Saururus chinensis Baill (ESCB) and one of its components, manassantin B, inhibited melanosome transport in Melan‐a melanocytes and normal human melanocytes (NHMs). Manassantin B disturbed melanosome transport by disrupting the interaction between melanophilin and myosin Va. Manassantin B is neither a direct nor an indirect inhibitor of tyrosinase. The total melanin content was not reduced when melanosome transport was inhibited in a Melan‐a melanocyte monoculture by manassantin B. Manassantin B decreased melanin content only when Melan‐a melanocytes were co‐cultured with SP‐1 keratinocytes or stimulated by α‐MSH. Therefore, we propose that specific inhibitors of melanosome transport, such as manassantin B, are potential candidate or lead compounds for the development of agents to treat undesirable hyperpigmentation of the skin. 相似文献
995.
996.
Sunghoon Jung Sunghun Lee Myungkwan Song Do‐Geun Kim Dae Sung You Jong‐Kuk Kim Chang Su Kim Tae‐Min Kim Kwon‐Hyeon Kim Jang‐Joo Kim Jae‐Wook Kang 《Liver Transplantation》2014,4(1)
Extremely flexible transparent conducting electrodes are developed using a combination of metal‐embedding architecture into plastic substrate and ultrathin transparent electrodes, which leads to highly transparent (optical transmittance ≈93% at a wavelength of 550 nm), highly conducting (sheet resistance ≈13 Ω □?1), and extremely flexible (bending radius ≈ 200 μm) electrodes. The electrodes are used to fabricate flexible organic solar cells and organic light‐emitting diodes that exhibit performance similar or superior to that of devices fabricated on glass substrates. Moreover, the flexible devices do not show degradation in their performance even after being folded with a radius of ≈200 μm. 相似文献
997.
Chulho Kim Min Uk Jang Mi Sun Oh Jong-Ho Park San Jung Ju-Hun Lee Kyung-Ho Yu Moon-Ku Han Beom Joon Kim Tai Hwan Park Sang-Soon Park Kyung Bok Lee Jae Kwan Cha Dae-Hyun Kim Jun Lee Sung-Hun Kim Soo Joo Lee Youngchai Ko Jong-Moo Park Kyusik Kang Young-Jin Cho Keun-Sik Hong Ki-Hyun Cho Joon-Tae Kim Dong-Eog Kim Jay Chol Choi Myung Suk Jang Hee-Joon Bae Byung-Chul Lee on the behalf of CRCS- investigators 《PloS one》2014,9(8)
Background and Purpose
The time of hospital arrival may have an effect on prognosis of various vascular diseases. We examined whether off-hour admission would affect the 3-month functional outcome in acute ischemic stroke patients admitted to tertiary hospitals.Methods
We analyzed the ‘off-hour effect’ in consecutive patients with acute ischemic stroke using multi-center prospective stroke registry. Work-hour admission was defined as when the patient arrived at the emergency department between 8 AM and 6 PM from Monday to Friday and between 8 AM and 1 PM on Saturday. Off-hour admission was defined as the rest of the work-hours and statutory holidays. Multivariable logistic regression was used to analyze the association between off-hour admission and 3-month unfavorable functional outcome defined as modified Rankin Scale (mRS) 3–6. Multivariable model included age, sex, risk factors, prehospital delay time, intravenous thrombolysis, stroke subtypes and severity as covariates.Results
A total of 7075 patients with acute ischemic stroke were included in this analysis: mean age, 67.5 (±13.0) years; male, 58.6%. In multivariable analysis, off-hour admission was not associated with unfavorable functional outcome (OR, 0.89; 95% CI, 0.72–1.09) and mortality (OR, 1.09; 95% CI, 0.77–1.54) at 3 months. Moreover, off-hour admission did not affect a statistically significant shift of 3-month mRS distributions (OR, 0.90; 95% CI, 0.78–1.05).Conclusions
‘Off-hour’ admission is not associated with an unfavorable 3-month functional outcome in acute ischemic stroke patients admitted to tertiary hospitals in Korea. This finding indicates that the off-hour effects could be overcome with well-organized stroke management strategies. 相似文献998.
Hyun Gi Kong Ju Young Bae Hyoung Ju Lee Hae Jin Joo Eun Joo Jung Eunsook Chung Seon-Woo Lee 《PloS one》2014,9(10)
Ralstonia solanacearum is the causal agent of bacterial wilt on a wide variety of plants, and enters a viable but nonculturable (VBNC) state under stress conditions in soil and water. Here, we adopted an artificial soil microcosm (ASM) to investigate the VBNC state of R. solanacearum induced by low temperature. The culturability of R. solanacearum strains SL341 and GMI1000 rapidly decreased at 4°C in modified ASM (mASM), while it was stably maintained at 25°C in mASM. We hypothesized that bacterial cells at 4°C in mASM are viable but nonculturable. Total protein profiles of SL341 cells at 4°C in mASM did not differ from those of SL341 culturable cells at 25°C in mASM. Moreover, the VBNC cells maintained in the mASM retained respiration activity. Catalase treatment effectively restored the culturability of nonculturable cells in mASM, while temperature increase or other treatments used for resuscitation of other bacteria were not effective. The resuscitated R. solanacearum from VBNC state displayed normal level of bacterial virulence on tomato plants compared with its original culturable bacteria. Expression of omp, oxyR, rpoS, dps, and the 16S rRNA gene quantified by RT-qPCR did not differ significantly between the culturable and VBNC states of R. solanacearum. Our results suggested that the VBNC bacterial cells in mASM induced by low temperature exist in a physiologically unique state. 相似文献
999.
Se Woong Kim Young Kwang Park Yoo Jin Joo Yu Jin Chun Ju Yeon Hwang Je-Hyun Baek Joon Kim 《Fungal biology》2019,123(10):709-722
Hyphal morphogenesis of Candida albicans is important for its pathogenesis. Here, we showed that the filamentous growth of C. albicans requires vacuolar H+-ATPase function. Results showed that levels of Vma4 and Vma10 increased in cells undergoing hyphal growth compared to those undergoing yeast growth. Deleting VMA4 or VMA10 abolished vacuolar functions and hyphal morphogenesis. These deletion mutants were also characterized as avirulent in a mouse model of systemic infection. Furthermore, VMA4 and VMA10 deletion strains showed hypersensitivity to fluconazole, terbinafine, and amphotericin B. Based on these findings, Vma4 and Vma10 are not only involved in vacuole biogenesis and hyphal formation, but also are good targets for antifungal drug development in C. albicans. 相似文献
1000.
Seung Ho Choi Seung Jong Lee Dong‐Joo Yoo Jun Ho Park Jae‐Hyuk Park You Na Ko Jungjin Park Yung‐Eun Sung Sung‐Yoon Chung Heejin Kim Jang Wook Choi 《Liver Transplantation》2019,9(41)
Due to unparalleled theoretical capacity and operation voltage, metallic Li is considered as the most attractive candidate for lithium‐ion battery anodes. However, Li metal electrodes suffer from uncontrolled dendrite growth and consequent interfacial instability, which result in an unacceptable level of performance in cycling stability and safety. Herein, it is reported that a marginal amount (1.5 at%) of magnesium (Mg) doping alters the surface properties of Li metal foil drastically in such a way that upon Li plating, a highly dense Li whisker layer is induced, instead of sharp dendrites, with enhanced interfacial stability and cycling performance. The effect of Mg doping is explained in terms of increased surface energy, which facilitates plating of Li onto the main surface over the existing whiskers. The present study offers a useful guideline for Li metal batteries, as it largely resolves the longstanding shortcoming of Li metal electrodes without significantly sacrificing their main advantages. 相似文献