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Background The protective effects of carbon monoxide against the lipopolysaccharide (LPS)-induced lung injury were attributed to maintenance of mitochondrial dynamics, but the mechanisms remain unexplored. Materials and methods Using a rat model of acute lung injury induced by LPS and the LPS attacking cell model, we investigated the effects of pretreatment of carbon monoxide molecule-2 (CORM-2) on the acute lung injury and expressions of mitofusin proteins that play a critical role in mitochondrial dynamics. Results We found that preadministration of CORM-2, not the inactive form of CORM-2, significantly reduced the lung injury, levels of inflammatory cytokines, and the degree of oxidative stress caused by LPS. What was more, it increased the expressions of mitofusin proteins. Similar findings were also found in LPS-stimulating cell model. However, when the cells were treated in combination with LPS, CORM-2, and SB203580, it completely abolished the protection of CORM-2, reflected by increased levels of inflammatory cytokines and malonaldehyde, decreased activities of superoxide dismutase, along with the lower expressions of mitofusin proteins and the ratio of p-p38 mitogen activated protein kinase to p38 mitogen activated protein kinase. Conclusions Our observations suggest that pretreatment with CORM-2 could attenuate LPS-induced lung injury by inducing the expressions of mitofusin proteins via p38 mitogen activated protein kinase pathway.

A new solvent extraction method recycling the acrylic acid (AA) from industrial waste fluid for producing acrylic acid was studied. The influencing factors of the species of diluents, concentration of extractant and temperature were investigated. The optimal process conditions were chosen that the 1-octanol as diluents, the concentration of tri-n-octylamine (TOA) 0.87mol/L, reaction temperature 298K after a series of experiments and analysis. The kinetics of extraction was studied by Lewis cell, the rate equation of extraction could be expressed as: RA=8.8×10-2[AA]1.5[TOA]2.1.

Extraction of citric acid from aqueous solutions with tertiary amine, dissolved in mixtures of kerosene and phase modifier have been studied as a function of exaction yield at different phase modifier volume fraction, temperatures, stirring speed and exaction time. The optimal experimental conditions of extraction were obtained: reaction temperature 303K, reaction time 3 min, the kerosene volume fraction 20%, and 45% 1−octanol as phase modifier, stirring speed 450rpm/min. Under these conditions, the extraction yield could reach 75%. The complex of citric acid and tertiary amine was a surfactant that makes surface tension decrease. The composition of the citric acid complex is (R3N) · (H3A). The formation of complex was exothermic reaction that the standard enthalpy change and standard entropy change are obtained: ΔHθ=-10.17kJ/mol, ΔSθ=-11.86J/(mol·K).

Background Sepsis-associated acute lung injury remains the major cause of mortality in critically ill patients and is characterized by marked oxidative stress and mitochondrial dysfunction. Mitochondrial dynamics are indispensable for functional integrity. Additionally, heme oxygenase (HO)-1/carbon monoxide conferred cytoprotection against end-organ damage during endotoxic shock. Herein, we tested the hypothesis that HO-1/carbon monoxide played a critical role in maintaining the dynamic process of mitochondrial fusion/fission to mitigate lung injury in Sprague-Dawley rats or RAW 264.7 macrophages exposed to endotoxin. Methods The production of reactive oxygen species, the respiratory control ratio (RCR), and the expressions of HO-1 and mitochondrial dynamic markers were determined in macrophages. Concurrently, alterations in the pathology of lung tissue, lipid peroxidation, and the expressions of the crucial dynamic proteins were detected in rats. Results Endotoxin caused a 31% increase in reactive oxygen species and a 41% decrease in RCR levels (n = 5 per group). In parallel, the increased expression of HO-1 was observed in lipopolysaccharide-stimulated macrophages, concomitantly with excessive mitochondrial fission. Furthermore, carbon monoxide-releasing molecule-2 or hemin normalized mitochondrial dynamics, which were abrogated by zinc protoporphyrin IX. Additionally, impaired mitochondrial dynamic balance was shown in Sprague-Dawley rats that received lipopolysaccharide, accompanied by pathologic injury, elevated malondialdehyde contents, decreased manganese superoxide dismutase activities, and lowered RCR levels in rat lung mitochondria. However, the above parameters were augmented by zinc protoporphyrin IX and were in turn reversed by hemin. Conclusions The HO-1/carbon monoxide system modulated the imbalance of the dynamic mitochondrial fusion/fission process evoked by lipopolysaccharide and efficiently ameliorated endotoxin-induced lung injury in vivo and in vitro.

Electroacupuncture at select acupoints have been verified to protect against organ dysfunctions during endotoxic shock. And, heme oxygenase (HO)-1 as a phase II enzyme and antioxidant contributed to the protection of kidney in septic shock rats. The phosphatidylinositol 3-kinase (PI3K)-Akt pathway mediated the activation of NF-E2 related factor-2 (Nrf2), which was involved in HO-1 induction. To understand the efficacy of electroacupuncture stimulation in ameliorating acute kidney injury (AKI) through the PI3K/Akt/Nrf2 pathway and subsequent HO-1 upregulation, a dose of LPS 5mg/kg was administered intravenously to replicate the rabbit model of AKI induced by endotoxic shock. Electroacupuncture pretreatment was handled bilaterally at Zusanli and Neiguan acupoints for five consecutive days while sham electroacupuncture at non-acupoints as control. Results displayed that electroacupuncture stimulation significantly alleviated the morphologic renal damage, attenuated renal tubular apoptosis, suppressed the elevated biochemical indicators of AKI caused by LPS, enhanced the expressions of phospho-Akt, HO-1protein, Nrf2 total and nucleoprotein, and highlighted the proportions of Nrf2 nucleoprotein as a parallel. Furthermore, partial protective effects of elecroacupuncture were counteracted by preconditioning with wortmannin (the selective PI3K inhibitor), indicating a direct involvement of PI3K/Akt pathway. Inconsistently, wortmannin pretreatment made little difference to the expressions of HO-1, Nrf2 nucleoprotein and total protein, which indicated that PI3K/Akt may be not the only pathway responsible for electroacupuncture-afforded protection against LPS-induced AKI. These findings provide new insights into the potential future clinical applications of electroacupuncture for AKI induced by endotoxic shock instead of traditional remedies.

We report a systematic solid-state (17)O NMR study of free nucleic acid bases: thymine (T), uracil (U), cytosine (C), and guanine (G). Site-specifically (17)O-enriched samples were synthesized:[2-(17)O]thymine (1), [4-(17)O]thymine (2), [2-(17)O]uracil (3), [4-(17)O]uracil (4), [2-(17)O]cytosine (5), and [6-(17)O]guanine monohydrate (6). Magic-angle-spinning (MAS) and static (17)O NMR spectra were acquired at 11.75 T for compounds 1-6, from which information about the (17)O chemical shift and electric field gradient tensors was obtained. Extensive quantum chemical calculations were performed at the B3LYP/6-311++G(d,p) level of theory for (17)O NMR properties in various molecular models. The calculated (17)O NMR tensors are highly sensitive to the description of intermolecular hydrogen-bonding interactions at the target oxygen atom. A reasonably good agreement between experimental solid-state (17)O NMR data and B3LYP/6-311++G(d,p) calculations is achievable only in molecular cluster models where a complete hydrogen-bond network is considered. Using this theoretical approach, we also investigated the (17)O NMR tensors in two unusual structures: guanine- and uracil-quartets.

We report a solid-state 17 O NMR study of [ α - 13 C , 17 O ] benzamide. The orientations of the 17 O electric-field-gradient and chemical shift tensors were determined from analysis of magic-angle spinning and stationary 17 O NMR spectra. The largest electric-field-gradient component lies in the amide plane and perpendicular to the 13 C– 17 O dipolar vector, whereas the intermediate electric-field-gradient component is along the CO bond. It is also found that the principal component of the 17 O chemical shift tensor with the least shielding, δ 11 , is approximately 18° off the CO bond and that the component with the most shielding, δ 33 , is perpendicular to the amide plane. The present study confirms our earlier results of quantum chemical calculations.

We have presented a systematic experimental and theoretical investigation of the carbonyl oxygen electric-field-gradient (EFG) tensor and chemical shielding (CS) tensor in crystalline amides. Three 17O-labled secondary amides, R1C[17O]-NHR2, have been synthesized: benzanilide (1), N-methylbenzamide (2), and acetanilide (3). Analysis of 17O magic-angle spinning (MAS) and stationary NMR spectra yields not only the magnitude but also the orientation of the carbonyl 17O EFG and CS tensors. For compounds 1−3, the carbonyl 17O quadrupolar coupling constant (QCC) and the span of the chemical shift tensor are found to be in the range of 8.5−8.97 MHz and 560−630 ppm, respectively. The largest 17O EFG component lies in the amide plane and is perpendicular to the CO bond, whereas the smallest component is perpendicular to the N−CO plane. For the carbonyl 17O CS tensor, the principal component with the largest shielding, δ33, is perpendicular to the amide plane, and the tensor component corresponding to the least sh...

We report the first experimental determination of the carbonyl 17O electric-field-gradient (EFG) tensor and chemical-shift (CS) tensor of a urea-type functional group, R1NHC(O)NHR2. Analysis of magic-angle spinning (MAS) and stationary 17O NMR spectra of crystalline [17O]urea yields not only the principal components of the carbonyl 17O EFG and CS tensors, but also their relative orientations. The carbonyl 17O quadrupole coupling constant (QCC) and the asymmetry parameter (η) in crystalline urea were found to be 7.24 ± 0.01 MHz and 0.92, respectively. The principal components of the 17O CS tensor were determined: δ11 = 300 ± 5, δ22 = 280 ± 5 and δ33 = 20 ± 5 ppm. The direction with the least shielding, δ11, is perpendicular to the CO bond and the principal component corresponding to the largest shielding, δ33, is perpendicular to the NC(O)N plane. The observed 17O CS tensor suggests that, in crystalline urea, the 17O paramagnetic shielding contributions from the σ → π* and π → σ* mixing are greater than t...

We report a solid-state 17O NMR study of the 17O electric field gradient (EFG) and chemical shielding (CS) tensors for the oxonium ion, H3O+, in p-toluenesulfonic acid monohydrate (TAM). Both the 1...

NF-E2 related factor 2 (Nrf2) is a major transcription factor and acts as a key regulator of antioxidant genes to exogenous stimulations. The aim of current study was to determine whether Nrf2/ARE pathway is involved in the protective effect of electroacupuncture on the injured lung in a rabbit model of endotoxic shock. A dose of lipopolysaccharide (LPS) 5 mg/kg was administered intravenously to replicate the model of acute lung injury induced by endotoxic shock. Electroacupuncture pretreatment was handled bilaterally at Zusanli and Feishu acupoints for five consecutive days while sham electroacupuncture punctured at non-acupoints. Fourty anesthetized New England male rabbits were randomized into normal control group (group C), LPS group (group L), electroacupuncture + LPS group (group EL) and sham electroacupuncture + LPS (group SEL). At 6 h after LPS administration, the animals were sacrificed and the blood samples were collected for biochemical measurements. The lungs were removed for calculation of wet-to-dry weight ratios (W/D), histopathologic examination, determination of heme oxygenase (HO)-1 protein and mRNA, Nrf2 total and nucleoprotein, as well as Nrf2 mRNA expression, and evaluation of the intracellular distribution of Nrf2 nucleoprotein. LPS caused extensive morphologic lung damage, which was lessened by electroacupuncture treatment. Besides, lung W/D ratios were significantly decreased, the level of malondialdehyde was inhibited, plasma levels of TNF-α and interleukin-6 were decreased, while the activities of superoxide dismutase, glutathione peroxidase and catalase were enhanced in the electroacupucnture treated animals. In addition, electroacupuncture stimulation distinctly increased the expressions of HO-1 and Nrf2 protein including Nrf2 total protein and nucleoprotein as well as mRNA in lung tissue, while these effects were blunted in the sham electroacupuncture group. We concluded that electroacupuncture treatment at ST36 and BL13 effectively attenuates lung injury in a rabbit model of endotoxic shock through activation of Nrf2/ARE pathway and following up-regulation of HO-1 expression.

The development of energetic azide binders and plasticizers for solid propellents in China is described in this article. Fourteen representatives of azides synthesized mainly by the authors on a small laboratory scale are involved. The reaction routes and conditions for preparing these azides are summerized; performance of the azides, including density, melting point, enthalpy of formation, thermal decomposition temperature determined by differential scanning calorimetry or differential thermal analysis, impact sensitivity, etc, were tested and are presented. The application of these azides to solid propellants or plastic-bonded explosives is still comparatively new in this country, with very little information available at the present time. A few results are briefly mentioned in this article. We arrange the stated azides under the following six categories: 1) azide poly ether: glycidyl azide polymer ([C3H5N3O])n, the homopolymer of 3,3-bis(azido methyl) oxetane (C5H8N6O) (BAMO), and the copolymer of BAMO/tetrahyd rofuran (C4H8O); 2) Azidonitramin e: l,5-diazido-3 -nitrazapentane, N~ nitro-N-azidomethylgemdinitroethyl methylamine, and N, ^V'-bis(azidomethylgemdinitroethyl)ethylenedinitramine; 3) Azidonitro compounds: 2-nitro-2-methyl-l,3-diazidopropane, 2-nitro-2-azidomethyl-l,3-diazidopropane, and l-azido-2-(2,4,6-trinitrophenyl)ethane; 4) aliphatic azide: l,2,4,triazidobutane and tetraazidomethylemethane; 5) Azidonitrate: pentaerythritol diazido dinitrate; and 6) oxygen heterocyclic azide: 3-azidomethyl-3-ethyloxetane, and 2,2-dimethyl-5-azidomethyl-5-nitro-l,3-dioxane.

We report the first experimental solid-state 17O NMR and theoretical (B3LYP/6-311++G**) study of the 17O electric-field-gradient and chemical shielding tensors in a free nucleic acid base, thymine.