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81.
Rajesh Mohandas Larysa Sautina Shiyu Li Xuerong Wen Tianyao Huo Eileen Handberg Yueh-Yun Chi C. Noel Bairey Merz Carl J. Pepine Mark S. Segal 《PloS one》2013,8(12)
Background
In women with ischemia and no obstructive coronary artery disease, the Women''s Ischemic Syndrome Evaluation (WISE) observed that microvascular coronary dysfunction (MCD) is the best independent predictor of adverse cardiovascular events. Since coronary microvascular tone is regulated in part by endothelium, we hypothesized that circulating endothelial cells (CEC), which reflect endothelial injury, and the number and function of bone-marrow derived angiogenic cells (BMDAC), which could help repair damaged endothelium, may serve as biomarkers for decreased coronary flow reserve (CFR) and MCD.Methods
We studied 32 women from the WISE cohort. CFR measurements in response to intracoronary adenosine were taken as an index of MCD. We enumerated BMDAC colonies and CEC in peripheral blood samples. BMDAC function was assessed by assay of migration of CD34+ cells toward SDF-1 and measurement of bioavailable nitric oxide (NO). These findings were compared with a healthy reference group and also entered into a multivariable model with CFR as the dependent variable.Results
Compared with a healthy reference group, women with MCD had lower numbers of BMDAC colonies [16 (0, 81) vs. 24 (14, 88); P = 0.01] and NO [936 (156, 1875) vs. 1168 (668, 1823); P = 0.02]. Multivariable regression analysis showed strong correlation of CFR to the combination of BMDAC colony count and CD34+ cell function (migration and NO) (R2 = 0.45; P<0.05).Conclusions
The BMDAC function and numbers of BMDAC colonies are decreased in symptomatic women with MCD and are independently associated with CFR. These circulating cells may provide mechanistic insights into MCD in women with ischemia. 相似文献82.
Jianjie Mi Alisa E. Shaw Chi W. Pak Keifer P. Walsh Laurie S. Minamide Barbara W. Bernstein Thomas B. Kuhn James R. Bamburg 《PloS one》2013,8(12)
Filament bundles (rods) of cofilin and actin (1:1) form in neurites of stressed neurons where they inhibit synaptic function. Live-cell imaging of rod formation is hampered by the fact that overexpression of a chimera of wild type cofilin with a fluorescent protein causes formation of spontaneous and persistent rods, which is exacerbated by the photostress of imaging. The study of rod induction in living cells calls for a rod reporter that does not cause spontaneous rods. From a study in which single cofilin surface residues were mutated, we identified a mutant, cofilinR21Q, which when fused with monomeric Red Fluorescent Protein (mRFP) and expressed several fold above endogenous cofilin, does not induce spontaneous rods even during the photostress of imaging. CofilinR21Q-mRFP only incorporates into rods when they form from endogenous proteins in stressed cells. In neurons, cofilinR21Q-mRFP reports on rods formed from endogenous cofilin and induced by all modes tested thus far. Rods have a half-life of 30–60 min upon removal of the inducer. Vesicle transport in neurites is arrested upon treatments that form rods and recovers as rods disappear. CofilinR21Q-mRFP is a genetically encoded rod reporter that is useful in live cell imaging studies of induced rod formation, including rod dynamics, and kinetics of rod elimination. 相似文献
83.
Ting Yan Guangdong Sun Weijie Chi Butong Li Haishun Wu 《Journal of molecular modeling》2013,19(9):3491-3499
A series of purine derivatives with nitramine groups are calculated by using density functional theory (DFT). The molecular theory density, heats of formation, bond dissociation energies and detonation performance are investigated at DFT-B3LYP/6-311G** level. The isodesmic reaction method is employed to calculate the HOFs of the energies obtained from electronic structure calculations. Results show that the position of nitramine groups can influence the values of HOFs. The bond dissociation energies and the impact sensitivity are analyzed to investigate the thermal stability of the purine derivatives. The calculated bond dissociation energies of ring-NHNO2 and NH-NO2 bond show that the NH-NO2 bond should be the trigger bond in pyrolysis processes. The H50 of most compounds are larger than that of CL-20 and RDX. 相似文献
84.
Computational studies on polynitropurines as potential high energy density materials 总被引:1,自引:0,他引:1
Ting Yan Wei-Jie Chi Jing Bai Lu-Lin Li Bu-Tong Li Hai-Shun Wu 《Journal of molecular modeling》2013,19(6):2235-2242
As part of a search for high energy density materials (HEDMs), a series of purine derivatives with nitro groups were designed computationally. The relationship between the structures and the performances of these polynitropurines was studied. Density functional theory (DFT) at the B3LYP/6-311G** level was employed to evaluate the heats of formation (HOFs) of the polynitropurines by designing an isodesmic reaction method. Results indicated that the HOFs were influenced by the number and positions of substituent groups. Detonation properties were evaluated using the Kamlet–Jacobs equations, based on the theoretical densities and heats of formation of the polynitropurines. The relative stabilities of the polynitropurines were studied via the pyrolysis mechanism and the UB3LYP/6-311G** method. Homolysis of the ring–NO2 bond is predicted to be the initial step in the thermal decomposition of these purine derivatives. Considering their detonation properties and relative stabilities, the tetranitropurine (D1) derivatives may be regarded as potential candidates for practical HEDCs. These results may provide useful information for further investigations. 相似文献
85.
Jianmei Luo Meiling Chi Hongyu Wang Huanhuan He Minghua Zhou 《Bioprocess and biosystems engineering》2013,36(12):1889-1896
A convenient and promising alternative to surface modification of carbon mesh anode was fulfilled by electrochemical oxidation in the electrolyte of nitric acid or ammonium nitrate at ambient temperature. It was confirmed that such an anode modification method was low cost and effective not only in improving the efficiency of power generation in microbial fuel cells (MFCs) for synthetic wastewater treatment, but also helping to reduce the period for MFCs start-up. The MFCs with anode modification in electrolyte of nitric acid performed the best, achieving a Coulombic efficiency enhancement of 71 %. As characterized, the electrochemical modification resulted in the decrease of the anode potential and internal resistance but the increase of current response and nitrogen-containing and oxygen-containing functional groups on the carbon surface, which might contribute to the enhancement on the performances of MFCs. 相似文献
86.
87.
目的:探讨地佐辛用于神经外科患者术后镇痛的效果和安全性。方法:将64例ASAⅠ~Ⅱ级行神经外科手术患者随机分为两组,术后均以静脉自控镇痛(PCIA),其中A组(34例)用地佐辛,B组(30例)用舒芬太尼,观察两组镇痛、镇静效果及不良反应。结果:术后4 h、8 h、12 h、24 h视觉模拟评分(VAS)和不良反应发生率A组明显低于B组(P〈0.05),Ramsay评分明显高于B组(P〈0.05)。结论:地佐辛用于神经外科患者术后镇痛确切,不良反应少。 相似文献
88.
Yu-Jue Wang Wen Liu Chi Chen Li-Meng Yan Jun Song Kun-Yuan Guo Gang Wang Qing-Hong Wu Wei-Wang Gu 《PloS one》2013,8(3)
Background
The radiation-induced energy metabolism dysfunction related to injury and radiation doses is largely elusive. The purpose of this study is to investigate the early response of energy metabolism in small intestinal tissue and its correlation with pathologic lesion after total body X-ray irradiation (TBI) in Tibet minipigs.Methods and Results
30 Tibet minipigs were assigned into 6 groups including 5 experimental groups and one control group with 6 animals each group. The minipigs in these experimental groups were subjected to a TBI of 2, 5, 8, 11, and 14 Gy, respectively. Small intestine tissues were collected at 24 h following X-ray exposure and analyzed by histology and high performance liquid chromatography (HPLC). DNA contents in this tissue were also examined. Irradiation causes pathologic lesions and mitochondrial abnormalities. The Deoxyribonucleic acid (DNA) content-corrected and uncorrected adenosine-triphosphate (ATP) and total adenine nucleotides (TAN) were significantly reduced in a dose-dependent manner by 2–8 Gy exposure, and no further reduction was observed over 8 Gy.Conclusion
TBI induced injury is highly dependent on the irradiation dosage in small intestine and inversely correlates with the energy metabolism, with its reduction potentially indicating the severity of injury. 相似文献89.
Myeloperoxidase (MPO) functions as a key molecular component of the host defense system against diverse pathogens. We have previously reported that increased MPO levels and activity is a distinguishing feature of rotenone-exposed glial cells, and that either overactivation or deficiency of MPO leads to pathological conditions in the brain. Here, we provide that modulation of MPO levels in glia by resveratrol confers protective effects on rotenone-induced neurotoxicity. We show that resveratrol significantly reduced MPO levels but did not trigger abnormal nitric oxide (NO) production in microglia and astrocytes. Resveratrol-induced down-regulation of MPO, in the absence of an associated overproduction of NO, markedly attenuated rotenone-triggered inflammatory responses including phagocytic activity and reactive oxygen species production in primary microglia and astrocytes. In addition, impaired responses of primary mixed glia from Mpo
−/− mice to rotenone were relieved by treatment with resveratrol. We further show that rotenone-induced neuronal injury, particularly dopaminergic cell death, was attenuated by resveratrol in neuron-glia co-cultures, but not in neurons cultured alone. Similar regulatory effects of resveratrol on MPO levels were observed in microglia treated with MPP+, another Parkinson’s disease-linked neurotoxin, supporting the beneficial effects of resveratrol on the brain. Collectively, our findings provide that resveratrol influences glial responses to rotenone by regulating both MPO and NO, and thus protects against rotenone-induced neuronal injury. 相似文献
90.
Hang Wun Raymond Li Vivian Chi Yan Lee Estella Yee Lan Lau William Shu Biu Yeung Pak Chung Ho Ernest Hung Yu Ng 《PloS one》2013,8(4)