BACKGROUND:To design and fabricate a novel three-dimensional thermoresponsive polymer cel scaffold is one of the hot topics in the research of polymer science. OBJECTIVE: To prepare three different kinds of thermoresponsive acelular carriers and to evaluate their performance. METHODS:The copolymer N-isopropylacrylamide temperature acelular scaffold, macroporous copolymer N-isopropylacrylamide temperature acelular scaffold and macroporous copolymer N-isopropylacrylamide crosslinking aldehyde sodium alginate thermoresponsive acelular scaffold were prepared. The specific surface area, thermoresponsive performance, porosity, pore size and biocompatibility of these three groups of scaffolds were determined. RESULTS AND CONCLUSION: The specific surface area of copolymer N-isopropylacrylamide thermoresponsive acelular scaffold, macroporous copolymer N-isopropylacrylamide thermoresponsive acelular scaffold and macroporous copolymer N-isopropylacrylamide crosslinking aldehyde sodium alginate thermoresponsive celular scaffold was respectively 135, 386, 421 m2/g. The lower critical solution temperature was 30, 28.5, 29.5℃. The cel toxicity reaction was respectively grade 2, 2, 1. These indicators showed that the three kinds of scaffolds were provided with a temperature-sensitive characteristics and similar lower critical solution temperature. The biocompatibility of macroporous copolymer N-isopropylacrylamide crosslinking aldehyde sodium alginate thermoresponsive acelular scaffold was significantly better than the other two scaffolds. The porosity and pore size of macroporous copolymer N-isopropylacrylamide thermoresponsive acelular scaffold and macroporous copolymer N-isopropylacrylamide crosslinking aldehyde sodium alginate thermoresponsive acelular scaffold were greater than those of the copolymer N-isopropylacrylamide thermoresponsive acelular scaffold (P < 0.05). These results demonstrate that macroporous copolymer N-isopropylacrylamide thermoresponsive acelular scaffold and macroporous copolymer N-isopropylacrylamide crosslinking aldehyde sodium alginate thermoresponsive acelular scaffold have more obvious pore structure.

A simple and selective HPLC method for simultaneous determination and quantification of anthraquinones, lignans and flavonoids in Xiao-Cheng-Qi Tang (XCQT), Hou-Po-San-Wu Tang (HPSWT) and Hou-Po-Da-Huang Tang (HPDHT) was developed and validated. An Agilent Zorbax SB-C 18 (4.6 mm x 250 mm, 5 µm) column with the mobile phase of acetonitrile and 0.5% acetic acid aqueous solution in gradient elution mode was used. The flow rate was 1.0 mL · min(-1) at 30 °C, and injection volume was 10 µL. The detection wavelength was set at 254 nm and 294 nm simultaneously for the quantitative analysis. The current HPLC assay was validated for linearity, intra-day and inter-day precisions, accuracy, recovery and stability. The method was applied to the content comparison of the gallic acid, cinnamic acid, sennoside A, sennoside B, rhein, emodin, aloe-emodin, chrysophanol, physcion, magnolol, honokiol, narirutin, naringin, hesperidin, neohesperidin, hesperetin, naringenin and nobiletin in XCQT, HPSWT and HPDHT. The good linear equations of eighteen constituents were obtained within the investigated ranges (r > 0.998). The recovery of the method was 94.28%-99.89% and the precision was less than 5%. The sample was stable within 16 h. There were some differences between the contents of anthraquinones, lignans and flavonoids in analogous formulae about XCQT. XCQT contained the greatest abundance of anthraquinones and flavonoid, HPSWT contained the greatest abundance lignans. In conclusion, the methods are simple, low-cost, precise, accurate and reliable for the determination of eighteen constituents in analogous formulae about XCQT, and these results provide methodological support for its quality control.

Objective To investigate the effects of Saussurea involucrate by cell culture on increasing the calcium content and bone density after 90 days feed in ovariectomized rats. Methods Osteoporosis model rats were induced by ovariectomy, treated with 16.7、33.3、100 mg/(kg?d)cell culture of Saussurea involucrate for 90 days. Body weight was observed, calcium content was measured through atomic absorption method and the bone density was detected by bone sonometers. Results cell culture of Saussurea involucrate(16.7、33.3、100 mg/kg)can increase the calcium content[(380.1 ± 1.9)mg/g、(370.7 ± 1.1)mg/g、(363.5 ± 2.4)mg/g] significantly(P<0.01)than the model group; increase distal femoral bone mineral density[(0.041 ± 0.017)g/cm2、(0.042±0.023)g/cm2、(0.040±0.008)g/cm2] significantly(P<0.01 or 0.05) than the model group(0.022±0.014)g/cm2; and also increase the middle femoral bone mineral density, the low-dose group (0.305±0.030)g/cm2 significantly (P<0.05) than the model group(0.259±0.061)g/cm2. Conclusion The cell culture of Saussurea involucrate has the effect of increasing the bone density.

To investigate the effect of huangqin tang on expression of cytokines and NF-κB p65 in rats with ulcerative colitis (UC), and to probe into its underlying mechanisms of action. The mode of UC rats with cell immunoreactivity was made using compound method (trinitrobenzene sulfonic acid and ethanol). Rats were randomly divided into control group, model group, SASP group and high dose, middle dose and low dose of huangqin tang group. The food intake, body weight and microscopic damage of rats in each group were evaluated after being treated for five days. The blood and colon tissue were also collected. Production of NO was detected by Griess assay, the expression levels of IL-6, TNF-α, PGE2 were detected by ELISA. ICH method was undertaken to determine the expression of NF-κB p65 protein in colon tissue. The food intake and body weight of model group rats were lower than that of control group. The expression levels of NO, IL-6, TNF-α, PGE2 in serum and NF-κB p65 protein of colon tissue in model group were higher than that of control group. The above indexes were ameliorated in high and middle dose of huangqin tang groups. But there was no significant difference with SASP group. NF-κB p65 may be involved in the pathogenesis of UC, and huangqin tang can inhibit the relative activity of NF-κB p65, and decrease the expression levels of NO, IL-6, TNF-α and PGE2.

The pharmacodynamic (PD) and pharmacokinetic (PK) properties of Huangqin Tang (HQT) were investigated in yeast-induced febrile rats. Blood sample and rectal temperature data of the rats were collected at different times after single oral administration of HQT at 20 g x kg(-1). The plasma concentrations of paeoniflorin, baicalin, wogonoside, baicalein, wogonin, oroxylin A, glycyrrhizic acid and glycyrrhetinic acid were quantified by a sensitive liquid chromatography-tandem mass spectrometric (LC-MS) method. The blood concentrations of PGE2, 1L-1β and TNF-α were detected by radioimmunoassay (RIA). All pharmacokinetic parameters were processed by non-compartmental analysis using WinNonlin software. The potential relationship between the mean concentration of eight constituents and the antifebrile efficacy was investigated by calculating Pearson correlation coefficients. It was found that HQT had significant antifebrile efficacy in yeast-induced febrile rats, but had no effect to normal rats. The antifebrile effect of HQT can be attributed to the inhibition of PGE2, 1L-1β and TNF-α. The constituents (baicalin, wogonoside, baicalein, wogonin, oroxylin A, glycyrrhizic acid and glycyrrhetinic acid) in febrile rats had delayed absorption and elimination, a longer residence time in the body, and higher C(max) and AUC than those in normal rats. Febrile condition could affect the pharmacokinetic behaviour of HQT in vivo; the flavonoids with the same backbone showed the similar fate in the body; baicalein and wogonin had a strong positive correlation (R > 0.66, P ≤ 0.02) with the antifebrile efficacy determined. Together, these constituents demonstrated different pharmacokinetic properties in the febrile body.

Objective To simulate the interaction between the stent graft (SG) and the aortic wall with finite element (FE) analysis by considering the influence of residual stress field, so as to study the stent influence on stress distributions of the aortic wall. Methods The three-dimensional (3D) residual stress field was generated in an idealized bi-layered thick-wall aortic model via a stress-driven anisotropic growth model by reducing the transmural stress gradient. Upon virtually deploying the SG, the stress on the aortic wall was calculated. Results The 3D residual stress field, corresponding to an opening angle of 117.5°, was shown to reduce the transmural stress gradient in both the circumferential and axial directions. The maximum stress was found at the contact area between aortic wall and wave peak of the stent. At 20% oversize ratio of the stent, the maximum stresses on the aortic wall in circumferential and axial direction were 412 and 132 kPa, respectively, while the in-plane shear stresses σrθ and σrz were both 78 kPa. Under residual stress, the maximum radial, circumferential and axial stresses were decreased by 14.9%, 40.5% and 33.8%, respectively, while the maximum shear stresses σrθ ，σrz，σθz were reduced by 2.5%, 7.1% and 27%, respectively. With the increase of oversize ratio from 10% to 20%, the maximum radial, circumferential and axial stresses were increased by 316%, 129% and 41%, respectively, while the maximum shear stresses σrθ ，σrz，σθz were increased by 661%, 450% and 466%, respectively. Conclusions The residual stress can effectively reduce the transmural stress gradient. Both the residual stress and the oversize ratio of the stent play an important role in modulating the wall stress distribution and the maximum stress.

The quality control processes for herbal medicines have been problematic. Flavonoids are the major active components of Huangqin Tang (HQT, a traditional Chinese medicine formula). In this study, we used a combinative method approach consisting of chromatographic fingerprinting (high performance liquid chromatography; HPLC), quantitative methods and a pharmacodynamic evaluation model to analyze the flavonoids of HQT obtained from different sources. Ten batches of HQT were analyzed by the HPLC fingerprinting method and 26 common peaks were detected, of which 23 peaks corresponded with the chemical profile of HQT. In addition, 11 major compounds were identified by LC-MS analysis (liquid chromatography-tandem mass spectrometer; LC-MS (n) ) and quantified by the HPLC quantitative method approach. The studied 10 batches of HQT were found to be homogeneous in their composition with a similarity between 0.990 and 1.000. The distribution of the 11 identified compounds was found to be very similar among the batches. Only slight pharmacodynamic differences were detected between the different batches, confirming the homogeneity of HQT. The results of this study prove that the combination of chromatographic fingerprinting and quantitative analysis can be readily used for comprehensive quality control of herbal medicines.