Stabilization of Positive Systems With Time Delay via the Takagi-Sugeno Fuzzy Impulsive Control.

In this study, the Takagi-Sugeno (T-S) fuzzy impulsive control problem is investigated for a class of nonlinear positive systems with time delay. The time delay under consideration is both in the continuous-time dynamics and at the impulsive instants, which can model practical systems more accurately. An impulse-time-dependent copositive Lyapunov function (IDCLF) is constructed, and the Razumikhin technique is adopted to develop conditions that ensure the globally exponential stability of T-S fuzzy positive systems with delayed impulses. The size constraint between the impulse delay and the bound of impulsive intervals is removed. A T-S fuzzy impulsive controller is designed in terms of the solutions to certain vector inequalities that are readily solvable. Numerical examples and a practical example of lipoprotein metabolism and potassium ion transfer model are given to demonstrate the effectiveness, advantages, and practicality of the proposed results.

Acupuncture at Gastric Back-Shu and Front-Mu Acupoints Enhances Gastric Motility via the Inhibition of the Glutamatergic System in the Hippocampus.

Acupuncture strongly alleviates gastrointestinal symptoms and especially promotes gastrointestinal motility. However, the mechanism underlying these processes is poorly understood. This study was designed to examine the effect of electroacupuncture (EA) at gastric back-shu (BL21) and front-mu (RN12) acupoints on gastric motility in functional dyspepsia (FD) rats and to investigate the mechanisms of its effects on the glutamatergic system in the hippocampus. We found that EA at RN12 or BL21 enhanced gastric motility in FD rats, whereas EA at the combination of RN12 and BL21 showed an additional effect. Microdialysis combined with HPLC showed that EA reduced the glutamate content in the hippocampus, and the NMDAR-NO-cGMP signalling pathway was downregulated, as determined by Western blot assays, in FD rats. In addition, we found that decreased gastric motility was significantly restored by the hippocampal infusion of an NMDAR, nNOS, or sGC antagonist. Interestingly, EA had no further effects on gastric motility in the presence of these antagonists in FD rats. Taken together, these results suggest that the hippocampal glutamatergic system is involved in the regulation of gastric motility by EA at RN12 and BL21.

[Role of hippocampus NMDAR subunits in electroacupuncture at "Zhongwan" (CV 12) and "Weishu" (BL 21) for gastric motility].

OBJECTIVE: To observe the effects of electroacupuncture (EA) on gastric motility, protooncogene c-fos and hippocampus N-methyl-D-aspartate (NMDA) receptor subunits in rats with functional dyspepsia (FD), and to discuss the molecular mechanism of hippocampal in EA at "Zhongwan" (CV 12) and "Weishu" (BL 21) for gastric motility. METHODS: Eighty-four Sprague Dawley (SD) rats were randomly divided into a normal group, a model group, a Zhongwan group, a Weishu group, an acupoint combination group and a non-acupoint group, 14 rats in each one. Except for the normal group, FD model were established by moderate tail-clipping infuriation method and irregular feeding. The rats in the Zhongwan group, Weishu group, acupoint combination group and non-acupoint group were treated with EA at corresponding acupoints, 20 min per treatment, once a day for 7 days. The rats in the normal group and the model group received no treatment; grabbing and fixation were applied in the model group. The stress transducer was used to record gastric motion waveforms; immunohistochemistry method was used to detect the expression of c-fos in hippocampus; Western blot method was used to detect the expression of NMDA receptor subunits NR1, NR2A and NR2B in hippocampus. RESULTS: Compared with the normal group, the gastric motility range was decreased (P<0.05), and the expression of hippocampus NR2A was reduced and the levels of NR1 and NR2B were increased in the model group (P<0.05), however, hippocampus c-fos expression was not significant different between the normal group and the model group (P>0.05). Compared with the model group, the gastric motility range was increased, the expression of hippocampus c-fos and expression of hippocampus NR2A was increased but expressions of NR1 and NR2B were reduced in the Weishu group, Zhongwan group and acupoint combination group (P<0.05). Besides, the differences of gastric motility range and expression of hippocampus c-fos, NR1, NR2A and NR2B between the model group and the non-acupoint were not significant (P>0.05). Compared with the Zhongwan group and the Weishu group, the gastric motility range was increased, the expression of hippocampus c-fos and NR2A was increased but the expression of NR1 and NR2B was reducedin the acupoint combination group (P<0.05). There was no significant difference in the frequency of gastric motility among the groups (P>0.05). CONCLUSION: EA at "Zhongwan" (CV 12) and "Weishu" (BL 21) could increase gastric motility of FD rats, which is likely to be related with activating hippocampal neurons, upregulating the level of NR2A and downregulating NR1 and NR2B.

Cardiac glycosides from the bark of Antiaris toxicaria.

Five new cardiac glycosides (1-5, namely antiaroside Y-ZC) together with 19 known compounds were obtained from the bark of Antiaris toxicaria. Their chemical structures were determined by IR, HR-ESI-MS, 1D and 2D NMR (HSQC, (1)H-(1)H COSY, HMBC, ROESY). The absolute configuration of sugar unit was defined by acid hydrolysis and appropriate derivatization. Compound 1 was rare 5ß-H-10ß-H-19-nor-cardenolide, which might derive from decarboxylative derivative of 19-COOH cardenolide. The inhibitory effects of cardiac glycosides 1-11 on the viability of NIH-H460 lung cancer cells and their induction of Nur77 expression were evaluated and preliminary structure-activity relationship (SAR) was also discussed.

Antiproliferative cardiac glycosides from the latex of Antiaris toxicaria.

Phytochemical investigation of the latex of Antiaris toxicaria resulted in the isolation of 15 new [antiarosides J-X (1-15)] and 17 known cardiac glycosides. The effects of the cardiac glycosides on apoptosis and the expression of orphan nuclear receptor Nur77 were examined in human NIH-H460 lung cancer cells. Several of the cardiac glycosides induced apoptosis in lung cancer cells, which was accompanied by induction of Nur77 protein expression. Treatment of cancer cells with the cardiac glycosides resulted in translocation of the Nur77 protein from the nucleus to the cytoplasm and subsequent targeting to mitochondria. The results show that the cardiac glycosides exert their apoptotic effect through the Nur77-dependent apoptotic pathway.