[Dynamic Mechanisms of Groundwater Quality by Residual Contaminants of the Tanghe Wastewater Reservoir in Xiong'an New Area].

Tanghe wastewater reservoir(TWR) is located on the west side of Baiyangdian Lake in Xiong'an New Area, where sewage infiltration and irrigation has been taking place for 40 years, and a large number of contaminants have accumulated in the unsaturated zone. Identifying the mechanisms by which this combined system contributes to groundwater hydrochemical dynamics is important for the protection of the water environment in the area. Hydrogeochemical methods such as tracing and improved chlor-alkali index are used to analyze the spatial and temporal characteristics and evolution mechanisms of shallow groundwater. The study shows that the groundwater chemistry in the sewage reservoir area is SO4·HCO3-Na type, with an average sewage fraction of 48.4%, and the contribution of Na+ from ion exchange and halite dissolution is 29.9% and 8.6%, respectively. The chemical type of groundwater in the sewage irrigation area is SO4·HCO3-Na·Mg, the average sewage fraction is 58.3%, and Na+ consumption of ion exchange is 8.1%. The mix dilution of precipitation and irrigation leads to a reduction in the effluent fraction and saturation index in the groundwater, and promotes the adsorption of Na+ from groundwater into the soil. Denitrification in aquifers can effectively reduce groundwater nitrate pollution. In addition, the sewage fraction before and after the restoration of the reservoir was 61.5% and 49.3%, respectively. Pollutants retained in the sewage infiltration and irrigation combined system will continue to affect the quality of shallow groundwater with varying degrees of mixing and water-rock interaction driven by rainfall and irrigation.

[Effects of GBE50 on LPS/ATP induced NLRP3 inflammasome activation in primary rat microglia].

In this study, the anti-inflammatory mechanism of Ginkgo biloba extract 50 (GBE50) and its mechanism of action on NLRP3 inflammatory corpuscles were observed by primary microglia cells. LPS/ATP was used to stimulate microglia, and the best time for stimulation and optimal concentration of GBE50 were screened. Pro-inflammatory cytokine IL-1ß and TNF-α was determined by ELISA. Western blot was performed to observe the protein expression of NLRP3, ASC, caspase-1 and IL-1ß in cultured primary rat microglia. Effect of GBE50 on NLRP3 inflammatory corpuscle aggregation was detected by CO-IP. GBE50 (10 mg·L⁻¹) preconditioning could significantly inhibit the expression of LPS (100 µg·L⁻¹,12 h), ATP (5 mmol·L⁻¹, 30 min) induced primary microglia corpuscle associated protein, inflammatory corpuscle aggregation, and the release of inflammatory factors IL-6 and TNF-α. These results indicated that GBE50 could inhibit the secretion of inflammatory factors after microglia activation, which is related to down regulating the protein expression and activity of NLRP3 inflammatory corpuscle.

[Ginkgo biloba extract 50 inhibited beta-amyloid-induced oxidative stress in rats' hippocampal neurons: an experimental study].

OBJECTIVE To study the in vitro effect and mechanism of Ginkgo biloba Extract 50 (GBE50) for inhibiting beta-amyloid (Abeta)-induced oxidative stress in rats' hippocampal neurons. METHODS: The primary hippocampal neurons were cultured in vitro and divided into 4 groups, i. e. the normal control group (Ctrl), the Abeta group, the propanediol control group (PDO), and the six GBE50 concentrations groups (5, 10, 25, 50, 100, and 200 microg/mL). Excepted the Ctrl group, neurons were induced to oxidative stress by 20 gmolLAbeta25-35. The MTT and fluorescent probes labeling were used to observe the effect of GBE50 with different concentrations on the cell viability and the generation of intracellular reactive oxygen species (ROS) in neurons. Furthermore, Western blot was used to detect the cytoplasmic/total cytochrome C (Cyto C) ratio and total intracytoplasmal Cyto C, and the effect of the expression of oxidative stress-related protein Cyto C and activated Caspase-3 in three GBE50 concentrations groups (25, 50, and 100 microg/mL). RESULTS: Compared with the Ctrl group, the cell vitality was obviously lowered and intracellular ROS generation significantly increased after induction of 20 micromol/L Abeta25-35 (both P < 0.05). Compared with the Abeta group, the cell vitality was evidently improved after treated with different GBE50 doses. Except for 10 microg/mL, the cell vitality could be obviously elevated along with increased drug concentrations (P < 0.05). Meanwhile, the intracellular ROS generation decreased significantly in each GBE50 dose groups (P < 0.05). Abeta could increase the cytoplasmic/total Cyto C ratio and enhance the activated Caspase-3 expression significantly (P < 0.05). Compared with the Abeta group, among the three concentrations of GBE50, the Cyto C ratio was obviously lowered in the 100 microg/mL GBE50 group (P < 0.05), and the expression of activated Caspase-3 significantly decreased in 50 microg/mL and 100 microg/mL GBE50 groups (P < 0.05). CONCLUSIONS: 20 micromol/L Abeta25-35 could induce the generation of intracellular ROS in hippocampal neurons. GBE50 could inhibit Abeta induced intracellular oxidative stress of neurons through lowering the cytoplasmic/total Cyto C ratio and inhibiting the activation of apoptosis protein Caspase-3 expression.

GBE50 Attenuates Inflammatory Response by Inhibiting the p38 MAPK and NF- κ B Pathways in LPS-Stimulated Microglial Cells.

Overactivated microglia contribute to a variety of pathological conditions in the central nervous system. The major goal of the present study is to evaluate the potential suppressing effects of a new type of Ginko biloba extract, GBE50, on activated microglia which causes proinflammatory responses and to explore the underlying molecular mechanisms. Murine BV2 microglia cells, with or without pretreatmentof GBE50 at various concentrations, were activated by incubation with lipopolysaccharide (LPS). A series of biochemical and microscopic assays were performed to measure cell viability, cell morphology, release of tumor necrosis factor- α (TNF- α ) and interleukin-1 ß (IL-1 ß ), and signal transduction via the p38 MAPK and nuclear factor-kappa B (NF- κ B) p65 pathways. We found that GBE50 pretreatment suppressed LPS-induced morphological changes in BV2 cells. Moreover, GBE50 treatment significantly reduced the release of proinflammatory cytokines, TNF- α and IL-1 ß , and inhibited the associated signal transduction through the p38 MAPK and NF- κ B p65 pathways. These results demonstrated the anti-inflammatory effect of GBE50 on LPS-activated BV2 microglia cells, and indicated that GBE50 reduced the LPS-induced proinflammatory TNF- α and IL-1 ß release by inhibiting signal transduction through the NF- κ B p65 and p38 MAPK pathways. Our findings reveal, at least in part, the molecular basis underlying the anti-inflammatory effects of GBE50.

Cardio-protection by Ginkgo biloba extract 50 in rats with acute myocardial infarction is related to Na⁺-Ca²âº exchanger.

Ginkgo biloba has been used for medical purposes for centuries in traditional Chinese medicine. Ginkgo biloba extract 50 (GBE50) is a new standardized GBE product that matches the standardized German product as EGb761. This paper is aimed at studying the cardio-protection effects of GBE50 Salvia miltiorrhiza on myocardial function, area at risk, myocardial ultra-structure, and expression of calcium handling proteins in rat ischemic myocardium. Myocardium ischemia was induced by the left anterior descending (LAD) coronary artery occlusion and myocardial function was recorded by a transducer advanced into the left ventricle on a computer system. In vitro myocardial infarction was measured by 2,3,5-triphenyltetrazolium chloride (TTC) and Evans blue staining of heart sections. Morphological change was evaluated by electric microscopy and Western blotting was used for protein expression. Hemodynamic experiments in vivo showed that postischemic cardiac contractile function was reduced in ischemic rats. Salvia miltiorrhiza (7.5 g/kg/d×7) and Ginkgo biloba extract 50 (GBE50) (100 mg/kg/d×7) improved post-schemic cardiac diastolic dysfunction while not affecting the systolic function. In hearts of GBE50 group and Salvia miltiorrhiza (SM) group, the area at risk was significantly reduced and myocardial structure was better-preserved. Moreover, Na⁺-Ca²âº exchanger (NCX) expression increase and sarcoplasmic reticulum Ca²âº-ATPase 2 (SERCA2), LTCC, and ryanodine receptor 2 (RyR2) expression decreases were smaller than those in ischemia group. There was a significant difference between the GBE50 and ischemia group in NCX expression. GBE50 could improve recovery in contractile function and prevent myocardium from ischemia damage, which may be caused by attenuating the abnormal expression of NCX.

Safety and efficacy of nano lamellar TiN coatings on nitinol atrial septal defect occluders in vivo.

Atrial septal defect (ASD) occlusion devices made of nickel-titanium (NiTi) have a major shortcoming in that they release nickel into the body. We modified NiTi occluders using Arc Ion Plating technology. Nano lamellar titanium-nitrogen (TiN) coatings were formed on the surfaces of the occluders. The safety and efficacy of the modified NiTi occluders were evaluated in animal model. The results showed that 38 out of 39 rams (97%) survived at the end of the experiment. Fibrous capsules formed on the surfaces of the devices. Gradual endothelialization took place through the attachment of endothelial progenitor cells from the blood and the migration of endothelial cells from adjacent endocardium. The neo-endocardium formed more quickly in the coated group than in the uncoated group, as indicated by the evaluation of the six month study group. After TiN coating, there was no significant difference in endothelial cell cycle. TiN coating significantly reduced the release of nickel in both in vivo and in vitro indicating an improved biocompatibility of the nitinol ASD occluders. Superior and modified ASD occluders may provide a good choice for people with nickel allergies after sFDA registration, which is expected in one to two years.

[Effects of Ginkgo biloba extract 50 on inflammatory cytokines and glia cell ultrastructures in the prefrontal cortex and hippocampus of aging rats].

OBJECTIVE: To study the effects of Ginkgo biloba extract 50 (GBE50) on inflammatory cytokines and glia cell injury in the prefrontal cortex and hippocampus of aging rats and its probable mechanism. Methods Totally 45 male SD rats were randomly divided into 4 groups, i.e., the normal control group (n=12), the model group (n=11), the low dose GBE50 group (n=10), and the high dose GBE50 group (n=12). The aging rat model was intraperitoneally injected with D-galactose to establish the aging model for 42 days. Starting from the 22nd day of modeling, rats in the low dose GBE50 group and the high dose GBE50 group were administered by gastrogavage with 75 mg/kg and 150 mg/kg respectively. The protein contents and mRNA expressions of IL-1beta, IL-6, and TNF-a in the prefrontal cortex and hippocampus of rats were detected by radioimmunoassay and Real-time fluorescence quantitative PCR assay respectively. The ultrastructural changes of glia cells in the hippocampal CA1 region were observed by transmission electron microscope. Results The protein contents and mRNA expressions of IL-1beta and TNF-alpha in the prefrontal cortex and the hippocampus of aging rats obviously increased when compared with the normal control group (P < 0.05, P < 0.01). The content of IL-6 in the hippocampus of aging rats obviously decreased (P < 0.01). Compared with the model group, the protein content and mRNA expression of IL-1beta in the prefrontal cortex and the hippocampus were obviously downregulated in the low and high dose GBE50 groups. The content of TNF-alpha in the prefrontal cortex was obviously downregulated in the low and high dose GBE50 groups, the content of TNF-alpha in the hippocampus was obviously downregulated in the low dose GBE50 group (P < 0.05, P < 0.01). The content of IL-6 in the prefrontal cortex of the low dose GBE50 group was up-regulated. The content of IL-6 in the hippocampus of the high dose GBE50 group was also upregulated. The mRNA expression of IL-6 in the prefrontal cortex of the low and high dose GBE50 groups obviously increased (P < 0.05, P < 0.01). Low and high dose GBE50 showed obvious recovery on the ultrastructural damage of glia cells in the hippocampal CA1 region. CONCLUSIONS: GBE50 showed inhibitive effects on the inflammatory reaction of nerves of aging rats. Its mechanism might be possibly correlated with its regulatory effects on the cytokines in the prefrontal cortex and the hippocampus, as well as the ultrastructures of glia cells in the prefrontal cortex and hippocampus to some degree.

Subensemble decomposition and Markov process analysis of Burgers turbulence.

A numerical and statistical study is performed to describe the positive and negative local subgrid energy fluxes in the one-dimensional random-force-driven Burgers turbulence (Burgulence). We use a subensemble method to decompose the field into shock wave and rarefaction wave subensembles by group velocity difference. We observe that the shock wave subensemble shows a strong intermittency which dominates the whole Burgulence field, while the rarefaction wave subensemble satisfies the Kolmogorov 1941 (K41) scaling law. We calculate the two subensemble probabilities and find that in the inertial range they maintain scale invariance, which is the important feature of turbulence self-similarity. We reveal that the interconversion of shock and rarefaction waves during the equation's evolution displays in accordance with a Markov process, which has a stationary transition probability matrix with the elements satisfying universal functions and, when the time interval is much greater than the corresponding characteristic value, exhibits the scale-invariant property.

Three-dimensional synthetic turbulence constructed by spatially randomized fractal interpolation.

A spatially randomized fractal interpolation algorithm to construct three-dimensional synthetic turbulence from original coarse field is reported. As in the one-dimensional case by Ding et al. (Phys. Rev. E 82, 036311, 2010), during the fractal interpolation, positions mapping between large and small scale cubes are chosen randomly, and the stretching factors are drawn from a log-Poisson random multiplicative process. A linear combination function defined as the base part in fractal interpolation and a theoretical energy spectrum model for fully developed turbulence are introduced into the procedure. Statistical analysis shows that the synthetic field displays some properties very close to the direct numeric simulated field, such as probability distributions of velocity, velocity gradient, velocity increment, and the anomalous scaling behavior of the longitude velocity structure functions, which follows the SL94 model precisely. After a short time using direct numeric simulation with the synthetic field as initial data, the typical local dynamical structures described by the teardrop shape of the Q-R plane for empirical turbulence can be reproduced.

[Study on chemical constituents from the root of Hemerocallis citrina].

OBJECTIVE: To study the chemical constituents root of Hemerocallis citrina. METHODS: The chemical constituents were extracted by microwave method and purified by silica gel column. Their structures were elucidated by their physical and chemical properties and spectral methods. RESULTS: 7 compounds were isolated and identified as: chrysophanol(I), 2-methoxy-obtusifolin(II), obtusifolin (III), rhein (IV), aloe-emodin (V), hemerocallone ( VI) and hemerocallin (VII). CONCLUSION: Compounds IV and VI are isolated from this plant for the first time.

[Effect of precondition with GBE50 and Salviae miltionrrhizae on cycloxygenase-2 and its downstream effectors contents in ischemia/reperfusion myocardium].

OBJECTIVE: To investigate the changes in contents of cycloxygenase-2 (COX-2) and its downstream effectors in rat's myocardial ischemia/reperfusion (I/R) model and observe the effects of precondition with GBE50 (Ginkgo biloba extract 50) and Salviae miltiorrhizae (SM) on them. METHODS: Rat's I/R model was established by 30-min left anterior descending coronary artery occlusion followed with 60-min reperfusion. Animals were divided into the model control group, the sham-operated group and the tested groups (received 1-week precondition with GBE50 and SM respectively via intragastric infusion before modeling). COX-2 mRNA expression in myocardium was detected by real-time PCR; contents of thromboxane B2 (TXB2) and 6-keto-prostaglandin F1alpha (6-keto-PGF1alpha) were measured by radioimmunoassay. RESULTS: The mRNA expression of COX-2 in the model group was obviously higher than that in the sham-operated group (P < 0.001), while that in the tested groups was down-regulated significantly (P < 0.01), and the content of TXB2 as well as the ratio of TXB2/PGF1alpha was reduced significantly (P < 0.05). Besides, SM also showed the up-regulation effect on 6-keto-PGF1alpha content in myocardium (P < 0.05). CONCLUSION: COX-2 affects the myocardium through thromboxane A2 and prostacyclin after I/R; both GBE50 and SM can inhibit the production of COX-2, but they may act in different paths.

[Effects of Ginkgo biloba extract 50 preconditioning on contents of inflammation-related cytokines in myocardium of rats with ischemia-reperfusion injury].

OBJECTIVE: To investigate the effects of Ginkgo biloba extract 50 (GBE50) preconditioning on contents of inflammation-related cytokines in rats with myocardial ischemia-reperfusion. METHODS: Fifty-eight SD rats were divided into sham-operated group, untreated group, Salviae miltiorrhizae (SM) injection group and low-, medium- and high-dose GBE50 groups. After intragastric administration for 7 d, the left anterior descending (LAD) coronary artery was occluded for 30 min followed by 60-min reperfusion to induce ischemia-reperfusion injury. Myocardium histopathologic change was observed by HE staining under a light microscope; myeloperoxidase (MPO) activity in myocardium was measured by colorimetric detection; tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and IL-8 were detected by radioimmunoassay; IL-4 and IL-10 were tested by enzyme-linked immunosorbent assay (ELISA). RESULTS: Compared with untreated group, rats in medium-dose GBE50 group had lower inflammatory reaction and MPO activity (P<0.01). GBE50 also decreased the content of IL-6 (P<0.05, P<0.01) and increased the content of IL-4 in myocardium (P<0.05, P<0.01) as compared with the untreated group. The content of TNF-alpha in myocardium in the medium-dose GBE50 group was lower and IL-10 was higher than those in the untreated group, but without significant differences. CONCLUSION: GBE50 can decrease the content of IL-6 and increase the content of IL-4 in myocardium after ischemia-reperfusion injury. It suggests that GBE50 can regulate the inflammatory reaction after ischemia-reperfusion injury via inhibiting inflammatory cytokines and promoting anti-inflammatory cytokines.

Synthetic turbulence constructed by spatially randomized fractal interpolation.

A spatially randomized fractal interpolation algorithm to construct synthetic fields with statistical properties close to real turbulence is proposed. It improves the previous works on fractal interpolation so that the position mapping between large and small scales is chosen randomly and the stretching factors are drawn from any chosen random multiplier model. In particular, using different parameters of Log-Poisson model, synthetic fields with absolute scaling properties close to SL94 model (for fully developed turbulence), K41 model and MB2000 model (for magnetohydrodynamic turbulence) are obtained, respectively. To model real turbulence fields which do not obey absolute scaling laws but ESS scaling laws, a refined technique is added. It is shown that both the velocity structure functions and the moments of subgrid-scale stress can be precisely predicted when the scale invariance is broken.

[Effect of GBE50 on delayed rectifier potassium current of ventricular myocytes in ischemic guinea pig].

OBJECTIVE: Ginkgo biloba extract 50 (GBE50) is a new multicomponent drug with a polyvalent action extracted from the leave of Ginkgo biloba. The aim of this experiment was to study the effects of GBE50 on delayed rectifier potassium current (I(K)) in ventricular myocytes under normal and simulated ischemia conditions in guinea pigs. METHODS: Single ventricular myocytes were isolated by an enzymatic dissociation method. I(K) were recorded by whole-cell patch clamp technique in voltage clamp mode. GBE50 was added to the perfusion chamber from low to high concentrations (25, 50,100 mg/L) in normal condition. Different concentrations of GBE50 (25, 50, 100 mg/L) were prepared with simulated ischemic fluid. RESULTS: (1) Under normal condition, 100 mg/L GBE50 decreased I(K) (n = 7, P < 0.05). (2) Under ischemia condition, it was observed that I(K) was inhibited (n = 8, P < 0.05). (3) Perfusion with ischemia solution containing 50 mg/L (n = 8, P > 0.05) and 100 mg/L GBE50 (n = 6, P > 0.05) could reverse the decrease of I(K). CONCLUSION: GBE50 significantly decreased I(K) in a concentration-dependent manner. GBE50 could alleviate the electrophysiological heterogeneity of myocardium to prevent ischemic myocardium from arrhythmia.

[Effect of electroacupuncture combined with Ginkgo biloba extract (GBE 50) on learning-memory ability and hippocampal cytokine levels in rats with dysmnesy].

OBJECTIVE: To observe the effect of electroacupuncture (EA) combined with Ginkgo biloba extract (GBE 50) on learning-memory ability and hippocampal cytokine contents in aging rats for exploring its underlying mechanism in the treatment of dysmnesy. METHODS: Forty-five SD rats were randomly divided into control (n=9), model (n=8), EA (n=10), GBE 50 (n=9) and EA + GBE 50 (n=9) groups. The dysmnesy model was established by D-galactose intraperitoneal injection for 42 days. EA (3 Hz, 1 mA) was applied to "Baihui" (GV 20) and "Zusanli" (ST 36) for 20 min, once every other day for 21 days. The learning-memory ability was detected by Morris water maze tests. The levels of IL-1beta, IL-6 and TNF-alpha in hippocampus were examined by radioimmunoassay. RESULTS: Compared with control group, the mean escape latency (MEL) of the rats in model group was significantly greater on the 2nd and 3rd day training (P<0.05, P<0.01), and the percent of swimming distance (PSD) in the target quadrant was shortened significantly (P<0.01). Compared with model group, the MEL values of the rats in EA, GBE 50 and EA + GBE 50 groups were significantly shortened (P<0.05, P<0.01), and the PSD values of the later 3 groups increased considerably (P<0.01). Comparison among the EA, GBE 50 and EA + GBE 50 groups showed that the MEL of EA + GBE 50 was obviously shorter than those of EA and GBE 50 groups (P<0.05). Compared with control group, the contents of IL-1beta) and TNF-alpha in hippocampus in model group increased significantly, but IL-6 decreased markedly (P<0.05, P<0.01). In comparison with model group, the IL-1beta contents of EA, GBE 50 and EA + GBE 50 groups, and TNF-alpha of EA and EA + GBE 50 groups were reduced significantly (P<0.05, P<0.01); and the contents of IL-6 in GBE 50 and EA + GBE 50 groups increased apparently (P<0.01). No significant differences were found between model and EA groups in IL-6 levels, and between model and EA + GBE 50 groups in hippocampal TNF-a levels (P>0.05). CONCLUSION: Both EA and GBE 50 can improve the dysmnesy rats' learning-memory ability, which may be closely associated with their effects in regulating hippocampal IL-1beta, IL-6 and TNF-alpha levels to relieve the inflammatory reaction. Combined administration of EA and GBE 50 has a synergic effect.

In vitro study of endothelial cells lining vascular grafts grown within the recipient's peritoneal cavity.

A living-tissue conduit with strong mechanical properties was used to produce small-diameter vessels. To improve blood compatibility, a shear-resistant confluent monolayer endothelium was formed on the luminal surface of the conduit. Under mechanical stimulation induced by pulsatile flow in a bioreactor, abrupt high-flow shear stress of 15.3 +/- 4.6 dynes/cm2 was applied to endothelial cells (ECs) seeded onto the lumen of a living-tissue conduit after 2 days of static culture. Scanning electron microscopy images revealed that most of the ECs were washed off after 3 days of dynamic culture. When shear stress was increased stepwise from 1.5 +/- 0.8 to 15.3 +/- 4.6 dynes/cm2 and applied to the ECs, scanning electron microscopy images of the luminal surface revealed that the confluent monolayer ECs were highly elongated and oriented to the flow direction, similar to findings in natural arteries in vivo. The results indicated that in vitro flow conditions played a key role in determining the durability of the EC layer. Careful design of the bioreactor and careful selection of the culture conditions will greatly improve the chances of producing a useful anti-thrombogenic surface for tissue-engineered small-diameter vessels.

[Effect of electroacupuncture on ethology and cytokines of hippocampus in rats with dysmnesy].

OBJECTIVE: To observe the effect of electroacupuncture (EA) on learning and memory impairment and cytokines of hippocampus in aging rats induced by D-galactose for exploring its underlying mechanism in the treatment of dysmnesy. METHODS: A total of 27 SD rats were randomly divided into control group (n = 9), model group (n = 8) and EA group (n = 10). Dysmnesy model was induced by intraperitoneal injection of D-galactose. EA (3 Hz, continuous waves, 1 mA) was applied to "Baihui" (GV 20) and "Zusanli" (ST 36) for 20 min every time and on alternate days, continuously for 21 days. Morris water maze tests were conducted to detect the rat's escape latency, percentage of swimming distance in the original platform quadrant and the total distance (SD/TD) and the percentage of swimming time in the platform quadrant after removal of the platform (spatial probe test) which were used for assessing the animals' learning and memory ability. The contents of IL-1beta, IL-6 and TNF-alpha in the hippocampus tissue were assayed by radioimmunoassay. RESULTS: Location navigation test showed that the escape latencies on the 2nd day and the 3rd day in model group were significantly longer than those of control group (P < 0.05), and the percents of SD/TD and swimming time in the platform quadrant were significantly lower than those of control group (P < 0.05, P < 0.01). In comparison with model group, the escape latency of EA group on the 3rd day was significantly shorter (P < 0.05), and the percent of SD/TD in the platform quadrant of EA group was significantly longer (P < 0.01). Compared with control group, IL-1beta and TNF-alpha contents in the hippocampus increased significantly in model group (P < 0.05, P < 0.01), while IL-6 content in model group decreased significantly (P < 0.01). In comparison with model group, the levels of IL-1beta and TNF-alpha in EA group decreased significantly (P < 0.05). CONCLUSION: EA can improve the learning-memory ability in dysmnesy rats, which may be closely associated with its effects in regulating the levels of cytokines in the hippocampus.

[Biocompatibility evaluation of chitosan-g-polyvinylpyrrolidone].

OBJECTIVE: To evaluate the biocompatibility of chitosan-g-polyvinylpyrrolidone as a new scaffold material. METHODS: The material was tested and measured for water absorption and contact angle, followed by evaluation of the biocompatibility by implantation into rabbits and in vitro cultured with the corneal epithelial cells. RESULTS: The water absorption rate of the material reached 1 100% with contact angle of 83-86. The results of implantation revealed partial degradation of the material 3 months after implantation, and much collagen and numerous corneal stromal cells appeared on the material without obvious inflammation reactions. In vitro coculture with epithelial cells showed good adhesion of the cells to the material which induced no obvious cytotoxicity. CONCLUSION: The novel chitosan derivative has excellent biocompatibility and can be used as a tissue scaffold material.

Effects of Ginkgolide B on action potential and calcium, potassium current in guinea pig ventricular myocytes.

AIM: To investigate the effect of Ginkgolide B (GB) on action potential (AP), delayed rectifier potassium current (IK), and L-type calcium current (I(Ca-L)) in guinea pig ventricular myocytes. METHODS: Single ventricular myocytes were isolated by an enzymatic dissociation method. AP, IK, I(Ca-L) were recorded by whole-cell patch-clamp technique in either current or voltage clamp mode. RESULTS: GB shortened APD in a concentration-dependent manner. GB 0.1, 1, and 10 micromol/L shortened APD50 by 7.9% (n=5, P>0.05), 18.4% (n=5, P<0.01), and 28.9% (n=6, P<0.01), respectively; APD90 by 12.4% (n=5, P>0.05), 17.6% (n=5, P<0.01), 26.4% (n=5, P<0.01), respectively. GB increased IK in a concentration-dependent manner. GB 0.1, 1, and 10 micromol/L increased IK by 20.1% (n=6, P<0.05), 43.1% (n=6, P<0.01), 55.6% (n=6, P<0.05); increased IK tail by 10.7% (n=6, P<0.05), 25.1% (n=6, P<0.05), and 37.7% (n=6, P<0.05), respectively at testing potential of +50 mV and shift the I-V curve of IK upward. But GB had no significant effect on I(Ca-L) at above concentrations. CONCLUSION: GB significantly shortened APD in a concentration-dependent manner which mainly due to increase of IK.