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101.
102.
CB Jonsson JV Camp A Wu H Zheng JL Kraenzle AE Biller CD Vanover YK Chu CK Ng M Proctor L Sherwood MC Steffen DJ Mollura 《PloS one》2012,7(7):e40094
Molecular imaging has gained attention as a possible approach for the study of the progression of inflammation and disease dynamics. Herein we used [18F]-2-deoxy-2-fluoro-D-glucose ([18F]-FDG) as a radiotracer for PET imaging coupled with CT (FDG-PET/CT) to gain insight into the spatiotemporal progression of the inflammatory response of ferrets infected with a clinical isolate of a pandemic influenza virus, H1N1 (H1N1pdm). The thoracic regions of mock- and H1N1pdm-infected ferrets were imaged prior to infection and at 1, 2, 3 and 6 days post-infection (DPI). On 1 DPI, FDG-PET/CT imaging revealed areas of consolidation in the right caudal lobe which corresponded with elevated [18F]-FDG uptake (maximum standardized uptake values (SUVMax), 4.7–7.0). By days 2 and 3, consolidation (CT) and inflammation ([18F]-FDG) appeared in the left caudal lobe. By 6 DPI, CT images showed extensive areas of patchy ground-glass opacities (GGO) and consolidations with the largest lesions having high SUVMax (6.0–7.6). Viral shedding and replication were detected in most nasal, throat and rectal swabs and nasal turbinates and lungs on 1, 2 and 3 DPI, but not on day 7, respectively. In conclusion, molecular imaging of infected ferrets revealed a progressive consolidation on CT with corresponding [18F]-FDG uptake. Strong positive correlations were measured between SUVMax and bronchiolitis-related pathologic scoring (Spearman’s ρ = 0.75). Importantly, the extensive areas of patchy GGO and consolidation seen on CT in the ferret model at 6 DPI are similar to that reported for human H1N1pdm infections. In summary, these first molecular imaging studies of lower respiratory infection with H1N1pdm show that FDG-PET can give insight into the spatiotemporal progression of the inflammation in real-time. 相似文献
103.
104.
Three new compounds, 1 – 3 , and 20 known compounds were isolated from the AcOEt and BuOH extract of edible Opuntia Milpa Alta. The petroleum ether extract was examined by GC and MS. A total of 26 compounds were identified, representing 95.6% of the total extract, phytosterol (36.03%) being the most abundant component, and polyunsaturated fatty acids (18.57%) represented the second largest group, followed by phytol (12.28%), palmitic acid, palmitate (13.54%), vitamin E (4.51%), and other compounds (7.47%). The effects of various extracts from edible Opuntia Milpa Alta (petroleum ether extract, AcOEt extract, BuOH extract, aqueous extract, H2O parts) and the positive control (received dimethylbiguanide) were tested on streptozotocin (STZ)‐induced diabetic mice. The results indicated that all the treatment groups could significantly decrease blood glucose levels in STZ‐induced diabetic mice compared to the model control group (P<0.01), except the aqueous extract group (P<0.05). Especially, the petroleum ether extract group and the positive control group showed remarkable decrease of blood glucose levels. Taken together, the results indicate that the petroleum ether extract is the major hypoglycemic part in edible Opuntia Milpa Alta, which may be developed to a potential natural hypoglycemic functional ingredient. 相似文献
105.
Linsheng Liu Jiye Aa Guangji Wang Bei Yan Xinwen Wang Bei Cao Mengjie Li Yuanting Zheng Fang Zhou Zimei Wu 《Analytical biochemistry》2010,406(2):105-6697
In metabolomic research, blood plasma and serum have been considered to possess similar compositions and properties. Their perceived equivalence has resulted in researchers choosing arbitrarily between serum and plasma for analysis. Here, routine serum and plasma were prepared and their low-molecular-weight compounds were determined using gas chromatography/time-of-flight mass spectrometry. Principal components analysis was applied to process the acquired data, and marked differences in metabolite profiles were observed between serum and plasma. Of the 72 identified compounds, 36 (50%) discriminate serum from plasma, with 29 and 7 metabolites showing a significantly higher abundance (t test, P < 0.05) in serum and plasma, respectively. Incubation of blood had distinct effects on the analyte peak areas, with the effects being more pronounced for plasma than for serum and more pronounced for a shorter incubation than for a longer incubation. These results highlight the importance in choosing serum or plasma as the analytical sample and in stipulating the incubation time. Because incubation affected the analyte peak areas less in serum than in plasma, we recommend serum as the sample of choice in metabolomic studies. 相似文献
106.
In Situ TEM Study of Volume Expansion in Porous Carbon Nanofiber/Sulfur Cathodes with Exceptional High‐Rate Performance 下载免费PDF全文
Zheng‐Long Xu Jian‐Qiu Huang Woon Gie Chong Xianying Qin Xiangyu Wang Limin Zhou Jang‐Kyo Kim 《Liver Transplantation》2017,7(9)
Although lithium sulfur batteries (LSBs) have attracted much interest owing to their high energy densities, synthesis of high‐rate cathodes and understanding their volume expansion behavior still remain challenging. Herein, electrospinning is used to prepare porous carbon nanofiber (PCNF) hosts, where both the pore volume and surface area are tailored by optimizing the sacrificial agent content and the activation temperature. Benefiting from the ameliorating functional features of high electrical conductivity, large pore volume, and Li ion permselective micropores, the PCNF/A550/S electrode activated at 550 °C exhibits a high sulfur loading of 71 wt%, a high capacity of 945 mA h g?1 at 1 C, and excellent high‐rate capability. The in situ transmission electron microscope examination reveals that the lithiation product, Li2S, is contained within the electrode with only ≈35% volume expansion and the carbon host remains intact without fracture. In contrast, the PCNF/A750/S electrode with damaged carbon spheres exhibits sulfur sublimation, a larger volume expansion of over 61%, and overflowing of Li2S, a testament to its poor cyclic stability. These findings provide, for the first time, a new insight into the correlation between volume expansion and electrochemical performance of the electrode, offering a potential design strategy to synthesize high‐rate and stable LSB cathodes. 相似文献
107.
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
108.
Two novel cyano‐containing oligo(phenylenevinylene) (OPV) derivatives have been designed and synthesized. Photophysical and sensing properties of the two compounds were studied. Such studies reveal the intramolecular charge transfer process between cyano groups and OPV core. The results showed that the alkyl difference of substituted OPV leads to the changes of molecular configuration and metallo‐response of two compounds. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
109.
Rong Li Di‐Dong Xie Jun‐hong Dong Hui Li Kang‐shuai Li Jing Su Lai‐Zhong Chen Yun‐Fei Xu Hong‐Mei Wang Zheng Gong Guo‐Ying Cui Xiao Yu Kai Wang Wei Yao Tao Xin Min‐Yong Li Kun‐Hong Xiao Xiao‐fei An Yuqing Huo Zhi‐gang Xu Jin‐Peng Sun Qi Pang 《Journal of neurochemistry》2014,128(2):315-329
Striatal‐enriched tyrosine phosphatase (STEP) is an important regulator of neuronal synaptic plasticity, and its abnormal level or activity contributes to cognitive disorders. One crucial downstream effector and direct substrate of STEP is extracellular signal‐regulated protein kinase (ERK), which has important functions in spine stabilisation and action potential transmission. The inhibition of STEP activity toward phospho‐ERK has the potential to treat neuronal diseases, but the detailed mechanism underlying the dephosphorylation of phospho‐ERK by STEP is not known. Therefore, we examined STEP activity toward para‐nitrophenyl phosphate, phospho‐tyrosine‐containing peptides, and the full‐length phospho‐ERK protein using STEP mutants with different structural features. STEP was found to be a highly efficient ERK tyrosine phosphatase that required both its N‐terminal regulatory region and key residues in its active site. Specifically, both kinase interaction motif (KIM) and kinase‐specific sequence of STEP were required for ERK interaction. In addition to the N‐terminal kinase‐specific sequence region, S245, hydrophobic residues L249/L251, and basic residues R242/R243 located in the KIM region were important in controlling STEP activity toward phospho‐ERK. Further kinetic experiments revealed subtle structural differences between STEP and HePTP that affected the interactions of their KIMs with ERK. Moreover, STEP recognised specific positions of a phospho‐ERK peptide sequence through its active site, and the contact of STEP F311 with phospho‐ERK V205 and T207 were crucial interactions. Taken together, our results not only provide the information for interactions between ERK and STEP, but will also help in the development of specific strategies to target STEP‐ERK recognition, which could serve as a potential therapy for neurological disorders.
110.
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