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In-situ formable double crosslinking chitosan/hyaluronan composite hydrogel was prepared with maleilated chitosan, thiol derivatised hyaluronan and chitosan via Michael addition reaction and physical crosslinking. The gelation time, swelling behaviors, mechanical properties and antibacterial ability of hydrogels were evaluated. Results showed that shorter gelation time, lower swelling ratio and higher storage modulus were observed in the double crosslinking hydrogels with the same thiol/vinyl molar ratios, due to the introduction of chitosan/β-glycerophosphate based physical cross-linked network into the initial chemical cross-linked gelling system. Furthermore, the hydrogels presented good antibacterial performance against Staphylococcus aureus.

Objective Functional magnetic resonance imaging (fMRI) analysis of the effects of acupuncturing the Tongli (HT5) and Tongli (HT5)–Xuanzhong (GB39) acupoints on the normal language areas with a view to providing a theoretical basis for using acupuncture to treat patients with aphasia. Methods This study enrolled healthy volunteers. The following acupoints were stimulated: right Tongli (HT5), right Tongli (HT5)–Xuanzhong (GB39), right Tongli (HT5) sham acupuncture, left Tongli (HT5), and left Tongli (HT5)–Xuanzhong (GB39) acupoints. Acupuncture stimulation was delivered whilst fMRI scanning of the brain was undertaken. Results Ten healthy volunteers (five males) were included in this study (mean age 44.5 ± 2.5 years; range 40–55 years). Based on the statistical analyses, only acupuncturing the right Tongli (HT5) acupoint resulted in activation of multiple regions of the bilateral cerebral hemisphere that were closely related to the language regions. The right Tongli (HT5) stimulation had a laterality index of 0.0952; with the activated voxels on the left side language-related areas being greater than those on the right side. Conclusions Acupuncturing the right Tongli (HT5) acupoint results in activation of the bilateral language-related areas, so this acupoint might be useful for the acupuncture treatment of aphasia caused by cerebral infarction.

Given the low permeability of clay (the main component of shale), diffusion is the main method for transport of methane in shale. Diffusion is a slower process than flow and permeation. Therefore, diffusion is a rate-controlling step during shale gas extraction. Diffusion of CH4 in clay mineral with water is investigated in detail. Dependences of self-diffusivity, Maxwell–Stefan (M–S) diffusivity and Fick diffusivity on various geological conditions are discussed. The practically important Fick diffusivity of methane in montmorillonite is calculated through molecular dynamics for the first time. Results show that self-diffusivity conventionally increases with temperature and its dependence on methane concentration follows the similar behavior of dependence on temperature. However, self-diffusivity displays a maximum at the water concentration of 2.5 molecules/unit-cell. The displacement distribution of CH4 calculated from molecule trajectory follows a logarithmic normal distribution, whose mean reaches the maximum at the same water concentration, resulting in the above-mentioned unusual behavior of self-diffusivity. M–S and Fick diffusivities go up with CH4 concentration and temperature while peak at the water content of 3.125 molecules/unit-cell. On the basis of self-diffusivity and M–S diffusivity, diffusion correlation parameter, Dii, among methane molecules is computed. The diffusion correlation increases with methane concentration, water content, and temperature. Consequently, high methane concentration, temperature and moderately increasing water content result in fast methane diffusion, whereas excessively high water concentration hinders methane diffusion.

Gray bricks and tiles are important materials of traditional buildings in China. However, the production process of bricks and tiles uses a large amount of clay resources from cultivated land, consumes a large amount of energy such as coal, and at the same time causes a great load to the environment. Therefore, the production process of traditional gray bricks and tiles is facing the risk of loss. This study investigates the traditional brick and tile manufacturers in Jiangsu and Zhejiang provinces and records the manufacturing techniques of traditional brick and tile blanks in detail, providing detailed records for the protection and repair of the architectural heritage.

This paper aims to compare the chemical and phase compositions of lime binders in ancient buildings. To this end, X-ray diffractometer (XRD) and FT-IR testing were used to analyse the representative samples by sampling the lime-based binding materials of several typical ancient buildings in China. The test results showed that the lime binder contained residual glutinous rice amylopectin; just because of this inorganic and organic synergistic effect of glutinous rice and lime can the lime binders have excellent properties. This provides a theoretical basis for the subsequent study.

Column chromatography has been widely used as a scalable purification strategy for recombinant adeno-associated virus (rAAV) vectors. The rAAV1, 2, 4, 5, 6, 8 and 9 serotypes could be separated using affinity resins, ion exchange resins or other types of resins. Apatite resin has displayed outstanding performance in protein purification in the past 10 years, and ceramic hydroxyapatite (CHT) chromatography resin with a polyethylene glycol (PEG) modulation has recently been used for rAAV1 and rAAV9 vectors. This study reports the use of CHT chromatography modulated by calcium ions instead of PEG for rAAV9 purification. Calcium-ion-containing buffers effectively improve the inclusion of CHT as a capture resin, the resin-binding capacity and the yield. The optimum calcium ion concentration is 30ppm, and the optimum pH is 7.0. A frontal analysis indicated that the binding capacity of CHT at 2ml/min reaches 65.1mg total protein per ml of resin. A previously developed purification strategy consists of CHT followed by ANX anion exchange chromatography. The vector yield of this approach is approximately 70%, and a software analysis indicated a vector purity exceeding 98%. The residual host cell (HEK293) protein contents are 24.75±2.32ng and 67.21±2.10ng, and the Benzonase residue contents are 1.55±0.10pg and 1.95±0.16ng per 10(13) vector genome copies (G.C.) separated by CHT/ANX and CsCl. In addition, CHT/ANX yields 798.44±50.10pg of plasmid DNA and 2.17±0.11ng of HEK293 DNA, while CsCl purification yields 840.27±76.14pg of plasmid DNA and 2.43±0.19 of HEK293 DNA. The two methods produce vectors with similar in vitro and in vivo potencies. The results indicated that the CHT/ANX method is suitable for the scalable purification of the rAAV9 vector.

MicroRNAs (miRNAs), a class of small, single-stranded endogenous RNAs, act as post-transcriptional regulators of gene expression. The ability of one single miRNA regulating multiple functionally related mRNAs makes it a new potential candidate for cancer gene therapy. Let-7s miRNAs have been demonstrated as tumor-suppressor genes in various types of cancers, providing one choice of gene therapy by replenishing this miRNA. In the present studies, we demonstrate that the chemically synthesized, double-stranded Let-7 mimics can inhibit the growth and migration and induce the cell cycle arrest of lung cancer cell lines in vitro. Let-7 mimics silence gene expression by binding to the 3' UTR of targeting mRNAs. Mutation of seed sequence significantly depresses the gene silencing activity of Let-7 mimics. Our results also demonstrate that it is possible to increase the activity of Let-7s through mutating the sequence within the 3'end of the antisense strand. Directly, co-transfection Let-7 mimics with active siRNAs impairs the anti-cancer activities of Let-7 mimics. However, a 3-h interval between the introduction of Let-7 mimics and a kind of siRNA avoids the competition and enhances the anti-cancer activities of Let-7 mimics. Taken together, these results have revealed that Let-7s mimics are potential candidates for cancer gene therapy.

The cytotoxicity profile of three chitosan derivatives with different affinity to water was evaluated in vitro. The derivatives selected were carboxymethylated-chitosan (CMCH), linoleic acid modified-chitosan (LACH) and deoxycholic acid modified-chitosan (DACH), respectively, and the results of FTIR and NMR confirmed the successful modification. Cytotoxicity of these polymers was investigated via the red blood cell lysis assay and the MTT assay. The red blood cell lysis test showed that CH elicited a certain level of red blood cell toxicity, while CMCH, LACH and DACH all displayed low membrane damaging effects, with the hemolysis rates of 2.385%, 1.560% and 4.404%, respectively, which comes well within permissible limit (5%). The MTT assay revealed that CH exhibited significant inhibitory effect on fibroblast proliferation at higher concentration, while its three derivatives showed no cytotoxicity. CMCH had stimulatory effects on fetal mouse fibroblast proliferation. Differences in cytotoxicity of CH and its derivatives may result from the specific chemical modifications leading to the alteration of molecular charge density and type of the cationic functionalities, structure and sequence, and conformational flexibility.

Attempts have been made by conventional gene therapy to suppress hepatic fibrogenesis, but potential oncogenic activity may prevent its clinical use. Recently, a novel major approach has been developed for resolution of liver fibrosis and cirrhosis: inactivation of hepatic stellate cells (HSC) using the endogenous expressing gene, which could mediate the homeostatic adaptation of liver. Cytoglobin (Cygb), originally identified in cultured rat HSC, is in a new class of heme containing proteins known as the hexacoordinate globin superfamily. These proteins exhibit peroxidase activity against hydrogen peroxides and lipid hydroperoxides. Considerable attention has been focused on the potential benefits of use of Cygb in fibrosis therapy, as up-regulation of Cygb expression could reduce oxidant stress, suppress HSC differentiation to a myofibroblast-like phenotype and eventually prevent the progress of liver fibrosis. Cygb has also been found to be a candidate tumor suppressor gene that might provide a new option for cancer gene therapy. In this review we systematically analyze the potential of Cygb as a prospective gene medicine for curing fibrosis, cancer, and other diseases such as diabetes. The molecular structure, regulation and subcellular location of Cygb are reviewed as well.

Prolonged inflammation and oxidative stress are emerging as key causes of pathological wound healing and the development of liver fibrosis. We have investigated the effects of recombinant human kallistatin, produced in Pichia. pastoris, on preventing carbon tetrachloride (CCl4)-induced liver fibrosis in rats. Daily administration of kallistatin prevented development of CCl4-induced liver fibrosis, which was evidenced by histological study. In all kallistatin treated rats, activation of hepatic stellate cells (HSC) as assessed by s-smooth muscle actin staining was attenuated, TGF- β1 expression was inhibited, class I serum biomarkers associated with the process of fibrogenesis, such as hyaluronic acid, laminin, and procollagen III, were lowered, compared with that in the model control group. Furthermore, residual hepatic functional reserve was improved by kallistatin treatment. CCl4 induced elevation of malondialdehyde level and reduced superoxide dismutase activity in the liver, while kallistatin reduced these oxidative parameters. We also investigated the effects of kallistatin on rat primary HSC and LX-2, the human HSC cell line. Kallistatin scavenged H2O2-induced ROS in the LX-2 cells, and suppressed the activation of primary HSC. These results suggest recombinant human kallistatin might be a promising drug candidate for therapeutic intervention of liver fibrosis.