Modulation of BmKAS-1 and BmK1-3-2 to sodium channel in rat dorsal root ganglion neurons

Objective To investigate what effects BmKAS 1 (a polypeptide purified from the Chinese scorpion Buthus martensi Karsch [BmK] and named as BmK activator of skeletal muscle ryanodine receptor) and its upstream mixture BmK1 3 2 have on Na + channels in dorsal root ganglion (DRG) small diameter neurons Methods The whole cell patch clamp technique was used to investigate the effects of BmKAS 1 and BmK1 3 2 on Na + current in rat small diameter DRG neurons Results About 50% peak Na + current was suppressed by 10?μg/ml of BmK1 3 2 1 62?μg/ml of BmKAS 1 also blocked 50% peak Na + current, and there was an obvious dose dependent relationship Conclusion Both BmK1 3 2 and BmKAS 1 have a blocking effect on Na + channels, and this may one of the mechanisms for the analgetic effect of BmK1 3 2 and BmKAS 1

Potassium channel AKT1 is involved in the auxin-mediated root growth inhibition in Arabidopsis response to low K^+stress

The changes in external K^＋ concentration affect plant root growth. However, the molecular mechanism for perceiving a K^＋ signal to modulate root growth remains unknown. It is hypothesized that the K^＋ channel AKTI is involved in low K^＋ sensing in the Arabidopsis root and subsequent regulation of root growth. Along with the decline of external K^＋ concentration, the primary root growth of wild-type plants was gradually inhibited. However, the primary root of the akt1 mutant could still grow under low K^＋（LK） conditions. Application of NAA inhibited akt1 root growth, but promoted wild-type root growth under LK conditions. By using the ProDR5：GFP and ProPIN1：PIN1-GFP lines, we found that LK treatment reduced auxin accumulation in wild-type root tips by degrading PIN1 proteins, which did not occur in the akt1 mutant. The LK-induced PIN1 degradation may be due to the inhibition of vesicle trafficking of PIN1 proteins. In conclusion, our findings indicate that AKT1 is required for an Arabidopsis response to changes in external K^＋, and subsequent regulation of K^＋-dependent root growth by modulating PINt degradation and auxin redistribution in the root.

Ecological wetland paradigm drives water source improvement in the stream network of Yangtze River Delta

Jiaxing created a precedent using bypass riparian marshes to purify micro-polluted water sources in China.Pond-wetland complex with constructed root channel technology becomes a paradigm which can be analogized as"human-body wetland model"based on bionics or biomimetics.Heterogeneous plant-bed/ditch system with highly active land/water ecotone interfaces,especially meandering boundaries,breeds many biochemical reactions"living areas".Optimization of hydraulic regulation promotes redox environment alternations and wetland treatment efficiency.Here we reported a series of upgrades and performances in Guanjinggang wetland after the Shijiuyang prototype.Morphological reform of plant-bed/ditch system played a vital role.Spatially root channel zone was main force of wetland purification,and temporally the treatment effect was higher in low-temperature seasons indicating non-temperature dependent mechanisms worked.Water pollution comprehensive index improved steadily from IV to III,and comprehensive pollution load was reduced by ca.40%–60%.Comprehensive evaluation function value further showed the gradients purification effect of the upgraded wetland.Ecological wetlands ameliorated source water quality,and reduced drinking water treatment reagents,thereby bringing about economic benefits.Through wetlands operation,people can see how the micro-polluted surface water becomes clear and clean,so promoting a significant social benefit.As a viable component of urban green space,wetlands could beautify regional eco-environment,freshen the air,increase urban ecological taste,and enhance the eco-environmental protection publicity.Thus,the multifunctional service values and indirect benefits are substantial.Jiaxing ecological wetlands provide a typical paradigm for water pollution remediation in developing countries and plays a leading role in technology engineering radiation effect.

Performance of pond–wetland complexes as a preliminary processor of drinking water sources

Shijiuyang Constructed Wetland（110 hm^2） is a drinking water source treatment wetland with primary structural units of ponds and plant-bed/ditch systems. The wetland can process about 250,000 tonnes of source water in the Xincheng River every day and supplies raw water for Shijiuyang Drinking Water Plant. Daily data for 28 months indicated that the major water quality indexes of source water had been improved by one grade. The percentage increase for dissolved oxygen and the removal rates of ammonia nitrogen, iron and manganese were 73.63%, 38.86%, 35.64%, and 22.14% respectively. The treatment performance weight of ponds and plant-bed/ditch systems was roughly equal but they treated different pollutants preferentially. Most water quality indexes had better treatment efficacy with increasing temperature and inlet concentrations. These results revealed that the pond–wetland complexes exhibited strong buffering capacity for source water quality improvement. The treatment cost of Shijiuyang Drinking Water Plant was reduced by about 30.3%. Regional rainfall significantly determined the external river water levels and adversely deteriorated the inlet water quality, thus suggesting that the ＂hidden＂ diffuse pollution in the multitudinous stream branches as well as their catchments should be the controlling emphases for river source water protection in the future. The combination of pond and plant-bed/ditch systems provides a successful paradigm for drinking water source pretreatment. Three other drinking water source treatment wetlands with ponds and plant-bed/ditch systems are in operation or construction in the stream networks of the Yangtze River Delta and more people will be benefited.

Modulation of Na_v1.8 by Lysophosphatidic Acid in the Induction of Bone Cancer Pain

Given that lysophosphatidic acid（LPA） and the tetrodotoxin-resistant sodium channel Na_v1.8 are both involved in bone cancer pain, the present study was designed to investigate whether crosstalk between the LPA receptor LPA_1（also known as EDG2） and Na_v1.8 in the dorsal root ganglion（DRG） contributes to the induction of bone cancer pain. We showed that the EDG2 antagonist Ki16198 blocked the mechanical allodynia induced by intrathecal LPA in na？ve rats and attenuated mechanical allodynia in a rat model of bone cancer. EDG2 and Na_v1.8expression in L_（4-6）DRGs was upregulated following intrathecal or hindpaw injection of LPA. EDG2 and Na_v1.8expression in ipsilateral L_（4-6）DRGs increased with the development of bone cancer. Furthermore, we showed that EDG2 co-localized with Na_v1.8 and LPA remarkably enhanced Na_v1.8 currents in DRG neurons, and this was blocked by either a protein kinase C（PKC） inhibitor or a PKCe inhibitor. Overall, we demonstrated the modulation of Na_v1.8 by LPA in DRG neurons, and that this probably underlies the peripheral mechanism by which bone cancer pain is induced.