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Wang H.,Ningxia Medical University | Wang H.,Ningxia Engineering and Technology Research Center for Modernization of Hui Medicine | Wang H.,Ningxia Research Institute of Medicine and Pharmacy | Laughton C.A.,University of Nottingham
Physical Chemistry Chemical Physics | Year: 2012

The PcrA DNA helicases are important bacterial enzymes and quintessential examples of molecular motors. Through conformational changes caused by ATP hydrolysis, they move along the template double helix, breaking the hydrogen bonds holding the two strands together, and separating the template chains so that the genetic information can be accessed. The flexibility of the DNA backbone is essential for the unidirectional translocation of PcrA. A modified DNA substrate with reduced backbone rotational flexibility (via an incorporated vinylphosphonate linkage) has previously been designed and tested as a helicase substrate. The results show that a single modification on the backbone is sufficient to inhibit the activity of PcrA. In this paper a range of molecular simulation methods have been applied to examine the structural origins of this inhibitory effect, as it tests our theories of the mechanism of action of this motor. We observe that the chemical modification has different effects on the energetics of DNA translocation through the protein as it reaches different sub-sites. © This journal is the Owner Societies 2012.

Zhang X.H.,Ningxia Medical University | Zhang X.H.,Gansu Agricultural University | Zhang X.H.,Ningxia Engineering and Technology Research Center for Modernization of Hui Medicine | Lang D.Y.,Ningxia Medical University | And 4 more authors.
Photosynthetica | Year: 2013

Diurnal dynamics of photosynthetic character of Angelica sinensis, as well as effect of continuous cropping on leaf photosynthetic character, antioxidant enzyme activity and growth of A. sinensis were investigated under field condition. The results showed that the diurnal net photosynthetic rate of A. sinensis in sunny day exhibited a double-peak pattern, and the peaks occurred at 9:45 and 16:45 h, respectively. There was a significant midday depression with A. sinensis, which was caused principally by stomatal factors such as stomatal conductance. The results also showed that net photosynthetic rate (PN), transpiration rate (E), stomatal conductance (gs), intercellular CO2 concentration (Ci), and chlorophyll content (Chl) of A. sinensis plants under continuous cropping were significantly lower than those of the control. The activity of total superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT), and growth parameters of A. sinensis plants were significantly decreased under continuous cropping condition. This study provides evidence of continuous cropping obstacle effect on photosynthesis, antioxidant enzyme activity, and growth parameters of A. sinensis in a field experiment, which partly explained the yield reduction of A. sinensis in the field, when it was cultivated continuously on the same soil. © 2013 Springer Science+Business Media Dordrecht.

Yang Y.,Ningxia Medical University | Jin S.-J.,Luohe Medical College | Wang H.-L.,Ningxia Medical University | Li Y.-X.,Ningxia Medical University | And 10 more authors.
Scandinavian Journal of Pain | Year: 2015

Background and objectives: Aloperine (ALO) is an alkaloid compound and presents in several medicinal plants. This study was undertaken to investigate the anti-nociceptive and anti-inflammatory activities of ALO on various chemical- and thermal-induced hypersensitivity models in mice. Methods: The anti-nociceptive effect of ALO was evaluated using acetic acid-induced writhing test, hot plate test, tail flick test, formalin test, ear swelling test, locomotor activity test, rota-rod test and carrageenan-induced paw edema test in mice. Inflammatory cytokines including interleukin-10 (IL-10), tumor necrosis factor α (TNF-α), interleukin-1 beta (IL-1β) and prostaglandin E2 (PGE2) expression were examined in ALO- and vehicle-treated mice. Results: The results showed that ALO significantly attenuated acetic acid-induced writhing numbers in mice in a dose-dependent manner. ALO showed no effect on prolonging latency in the hot plate test and the tail-flick test. ALO showed analgesic activity in the inflammatory phase of formalin-induced pain. Its anti-inflammatory effect was also confirmed in the ear-swelling test. In the carrageenan-induced paw edema model, ALO significantly and dose-dependently reduced the carrageenan-induced paw edema, decreased the contents of TNF-α, IL-1β and PGE2, but increased the IL-10 production. On the other hand, ALO showed no influence on the rota-rod performance time or on spontaneous locomotor activity. Conclusion: It is concluded that ALO has both anti-inflammatory and analgesic effects, especially in the field of inflammation pain. Implications: Our findings support the hypothesis that ALO ameliorates inflammatory pain induced by chemical and thermal stimuli and provides a scientific basis for the resource development and clinical use of aloperine. © 2015 Scandinavian Association for the Study of Pain.

Li J.,Ningxia Medical University | Li J.,Ningxia Engineering and Technology Research Center for Modernization of Hui Medicine | Niu Y.,Ningxia Medical University | Niu Y.,Key Laboratory of Hui Medicine Modernization | And 6 more authors.
Molecular Medicine Reports | Year: 2015

Microglia-mediated neuroinflammation is key in the pathogenesis of Alzheimer's disease (AD). Several studies have suggested that NADPH oxidase contributes to microglia-mediated neuroinflammation. Resveratrol, which is a natural polyphenolic compound, exerts neuroprotective effects in AD due to its anti-inflammatory properties. The present study aimed to investigate the effects of resveratrol on the activation of oligomeric amyloid β (oAβ)-induced BV-2 microglia, and to determine the role of NADPH oxidase in these effects. Microglial proliferation was measured by high-content screening cell counting and using a bromodeoxyuridine incorporation assay. In addition, the levels of reactive oxygen species (ROS), nitric oxide (NO), tumor necrosis factor (TNF)a and interleukin (IL)1β were assessed. The results of the present study demonstrated that resveratrol inhibited the proliferation of oAβ-induced microglia and the production of pro-inflammatory factors, including ROS, NO, TNF-a and IL-1β. Subsequent mechanistic investigations demonstrated that resveratrol inhibited the oAβ-induced mRNA and protein expression levels of p47phox and gp91phox. These results suggested that NADPH oxidase may be a potential target for AD treatment, and resveratrol may be a valuable natural product possessing therapeutic potential against AD.

Zhang X.H.,Ningxia Medical University | Zhang X.H.,Gansu Agricultural University | Zhang X.H.,Ningxia Engineering and Technology Research Center for Modernization of Hui Medicine | Lang D.Y.,Ningxia Medical University | And 2 more authors.
International Journal of Agriculture and Biology | Year: 2015

Aims and Methods A pot experiment was carried out to determine the effect of Angelica sinensis intercropped with garlic on A. sinensis growth and soil microbial communities in rhizosphere soil of A. sinensis under the scheme of A. sinensis intercropped with garlic. Results Soil microbial community was changed and bacteria functional group diversity was increased, and A. sinensis growth was improved when A. sinensis intercropped with garlic under the continuous cropping condition. Also, it shows that intercropping significantly increased root dry weight, and much less substantially shoot dry weight and plant height. Relative to the control, the activity of superoxide dismutase, peroxidase and catalase was increased by 80.00, 243.41 and 37.13%, respectively, but the content of malondialdehyde was decreased by 11.67%, along with a 70.13% yield improvement of A. sinensis, and 50.00% and 10.20% essential oil and alcohol-soluble extract increasing, respectively. The result also showed that the population of bacteria, aerobic cellulose-decomposing bacteria, organic phosphorus-solubilizing bacteria, inorganic phosphorus-solubilizing bacteria and potassium-solubilizing bacteria in rhizosphere soil were promoted in intercropping in vigorous growth stage. The abundance of aerobic cellulose-decomposing bacteria, organic phosphorussolubilizing bacteria and potassium-solubilizing bacteria in intercropping soils changed at the rootstock thickening. Although the total population of functional groups in intercropping A. sinensis rhizosphere soils was lower than in monocroping system, community diversity and evenness increased and dominance concentration decreased. Conclusions Intercropping A. sinensis with garlic can alleviate the soil sickness of A. sinensis. © 2015 Friends Science Publishers.

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