Evaluation of changes in magnetic resonance diffusion tensor imaging after treatment of delayed encephalopathy due to carbon monoxide poisoning.

Diffusion tensor imaging of the brain tissue microstructure was performed to predict or diagnose the pathophysiological mechanism underlying delayed encephalopathy after carbon monoxide poisoning and the treatment effect was analyzed. The changes in the diffusion parameters (average diffusion coefficient and fractional anisotropy) in adult patients after hyperbaric oxygen therapy of delayed encephalopathy after carbon monoxide poisoning were not significant differences of the two lateral ventricles or anterior or posterior limb of the internal capsule. In the group exposed to hyperbaric oxygen therapy, the fractional anisotropy values of the white matter in the ventricles of the brain and anterior and posterior limbs of the internal capsule were higher than those recorded before therapy, while the average diffusion coefficient values were significantly lower. These finding provide important monitoring indicators for clinicians.

Antitussive, expectorant, and anti-inflammatory activities of four caffeoylquinic acids isolated from Tussilago farfara.

CONTEXT: The flower bud of Tussilago farfara L. (Compositae) (FTF) is one of the traditional Chinese medicinal herbs used to treat cough, phlegm, bronchitic, and asthmatic conditions. OBJECTIVE: The objective of this study is to isolate four caffeoylquinic acids from the ethyl acetate extract (EtE) of FTF and to evaluate their antitussive, expectorant, and anti-inflammatory activities. MATERIALS AND METHODS: The structures of compounds 1-4 isolated from EtE were determined by spectral analysis. Mice were orally treated with these compounds and their mixture (in a ratio of 5:28:41:26 as in EtE) at doses of 10 and 20 mg/kg once daily for 3 d. The antitussive and expectorant activities were evaluated separately with the ammonia liquor-induced model and the phenol red secretion model. The anti-inflammation activity was evaluated using leukocyte count in the bronchoalveolar lavage fluid after ammonia liquor-induced acute airway inflammation. RESULTS: The four compounds were identified as chlorogenic acid (1), 3,5-dicaffeoylquinic acid (2), 3,4-dicaffeoylquinic acid (3), and 4,5-dicaffeoylquinic acid (4). All compounds, especially compound 4 (58.0% inhibition in cough frequency), showed a significant antitussive effect. However, the mixture was the most effective to inhibit the cough frequency by 61.7%. All compounds also showed a significant expectorant effect, while compound 2 was the most potent to enhance the phenol red secretion by 35.7%. All compounds significantly alleviated inflammation, but compound 4 showed the strongest effect to inhibit the leukocytosis by 49.7%. DISCUSSION AND CONCLUSION: The caffeoylquinic acids and their mixture, exhibiting significant antitussive, expectorant, and anti-inflammatory effects, could be considered as the main effective ingredients of FTF, and they may act in a collective and synergistic way.

Simultaneous separation and determination of phenolic acids, pentapeptides, and triterpenoid saponins in the root of Aster tataricus by high-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight mass spectrometry.

We established a qualitative method to analyze the main chemical compositions of the root of Aster tataricus. Most of the peaks were separated on a C(18) column packed with 5.0 µm particles, and 28 compounds were identified, including 11 chlorogenic acids, ten astins/asterinins, and seven astersaponins, four of which were reported for the first time from A. tataricus. Furthermore, we developed a reliable method for the simultaneous quantification of 3-caffeoylquinic acid, 3,4-dicaffeoylquinic acid, 3,5-dicaffeoylquinic acid, astin A, astin B, astin C, astersaponin A, and astersaponin C, and the qualified separations were achieved only on a C18 column packed with 2.7 µm particles. The method was used to measure the concentrations of eight components in samples from two major producing areas in China, and the average contents in samples from Bozhou (Anhui) were higher than those in samples from Anguo (Hebei).

A valuable visual colorimetric and electrochemical biosensor for porphyrin.

Porphyrin is able to specifically combine with phosphorus, thus a novel bifunctional sensing platform for determination of porphyrin by visual colorimetry and electrochemistry was demonstrated. A pretreated gold sheet (or electrode) with 2-mercatpoethanol (2-ME) was chemically modified by POCl(3) to obtain the surface phosphate active sites. The different stages of modified electrode were characterized by electrochemical impedance spectroscopy (EIS). The 1:1 cationic sitting-atop (SAT) complex P(V)-porphyrin was formed due to the high affinity of the modified gold sheet (or electrode) towards the porphyrin, resulting in electron transfer resistance increase of the electrode surface. Meanwhile, a dramatic color changing from burgundy to dark green of porphyrin solution was observed with the naked-eye within 3s. What's more, this was reflected by the notable change of the Soret band of porphyrin when using UV-vis. Two sensing systems provide different sensitivity for porphyrin analysis. With visual colorimetry, porphyrin can be detected at a level of 1.0×10(-6) M, whereas the detection limit of porphyrin is 3.0×10(-8) M using the EIS method. The practical application of the sensor to determination of pheophytin which was obtained from fresh spinach leaves has been accomplished. The results demonstrate the facility and effectivity of our introduced bifunctional biosensor for quantitative analysis of porphyrin.

Theoretical analysis of gas-phase front-side attack identity S(N)2(C) and S(N)2(Si) reactions with retention of configuration.

Gas-phase front-side attack identity S(N)2(C) and S(N)2(Si) reactions, CH(3)X1 + X2(-) --> CH(3)X2 + X1(-) and SiH(3)X1 + X2(-) --> SiH(3)X2 + X1(-) (X = F, Cl), are investigated by the ab initio method and molecular face (MF) theory. The computations have been performed at the CCSD(T)/aug-cc-pVTZ//MP2/6-311++G(3df,3pd) and CISD/aug-cc-pVDZ levels. Front-side attack identity S(N)2 reactions for both SiH(3)X and CH(3)X have double-well potential energy surfaces (PESs), but their transition-state positions are different relative to the positions of reactants and products: it is lower for SiH(3)X, and it is higher for CH(3)X. The minimum energy path for an S(N)2(Si) reaction with retention of configuration proceeds from a stable pentacoordinated anion intermediate of C(s) symmetry (TBP) via a C(s) transition state (SP) to a complementary pentacoordinated intermediate (TBP) and finally up to separate products. Berry pseudorotation has been observed in the front-side attack identity S(N)2(Si) reactions with F(-) and Cl(-) along the intrinsic reaction coordinate (IRC) routes. In addition, the geometrical transformations of front-side attack identity S(N)2(C) and S(N)2(Si) reactions based on the IRC calculations at the MP2/6-311++G(3df, 3pd) level of theory are described compared with those of corresponding back-side attack reactions. The difference between front-side attack identity S(N)2(C) and S(N)2(Si) reactions has been demonstrated. In MF theory, the potential acting on an electron in a molecule (PAEM) is an important quantity; in particular, its D(pb) can measure the strength of a chemical bond in a molecule. It is found that the difference between D(pb) values of reactant and transition state may be related to the activation energy for front-side and back-side attack S(N)2(C) and S(N)2(Si) reactions, and the D(pb) curves along the IRC routes have features similar to those of the potential energy profiles for all of the back-side attack S(N)2 reactions and front-side attack S(N)2(Si) reaction with F(-). Furthermore, according to the MF theory, the spatial dynamic changing features of the molecular shapes and the face electron density are vividly depicted for the course of the reactions.