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Chronic pain management represents a serious healthcare problem worldwide. The use of opioid analgesics for pain has always been hampered by their side effects; in particular, the addictive liability associated with chronic use. Finding a morphine replacement has been a long-standing goal in the field of analgesia. In traditional Chinese medicine, processed Buthus martensii Karsch (BmK) scorpion has been used as a painkiller to treat chronic inflammatory arthritis and spondylitis, so called "Scorpio-analgesia". However, the molecular basis and the underline mechanism for the Scorpio-analgesia are still unclear.The study aims to investigate the molecular basis of "Scorpio analgesia" and identify novel analgesics from BmK scorpion.In this study, the analgesic abilities were determined using formalin-, acetic acid- and complete Freund's adjuvant-induced pain models. The effect of BmK venom and processed BmK venom on Nav1.7 were detected by whole-cell voltage-clamp recordings on HEK293-hNav1.7 stable cell line. Action potentials in Dorsal root ganglion (DRG) neurons induced by Makatoxin-3-R58A were recorded in current-clamp mode. The content of Makatoxin-3 was detected using competitive enzyme-linked immunosorbent assay based on the Makatoxin-3 antibody. High performance liquid chromatography, western blot and circular dichroism spectroscopy were used to analysis the stability of Makatoxin-3.Here we demonstrate that Makatoxin-3, an α-like toxin in BmK scorpion venom targeting Nav1.7 is the critical component in Scorpio-analgesia. The analgesic effect of Makatoxin-3 could not be reversed by naloxone and is more potent than Nav1.7-selective inhibitors and non-steroidal anti-inflammatory drugs in inflammatory models. Moreover, a R58A mutant of Makatoxin-3 is capable of eliciting analgesia effect without inducing pain response.This study advances ion channel biology and proposes Nav1.7 agonists, rather than the presumed Nav1.7-only blockers, for non-narcotic relief of chronic pain.

To quantify the relationship between the soil organic matter and color parameters using the CIE-Lab system, 62 soil samples (0–10 cm, Ferralic Acrisols) from tea plantations were collected from southern China. After air-drying and sieving, numerical color information and reflectance spectra of soil samples were measured under laboratory conditions using an UltraScan VIS (HunterLab) spectrophotometer equipped with CIE-Lab color models. We found that soil total organic carbon (TOC) and nitrogen (TN) contents were negatively correlated with the L* value (lightness) (r = –0.84 and –0.80, respectively), a* value (correlation coefficient r = –0.51 and –0.46, respectively) and b* value (r = –0.76 and –0.70, respectively). There were also linear regressions between TOC and TN contents with the L* value and b* value. Results showed that color parameters from a spectrophotometer equipped with CIE-Lab color models can predict TOC contents well for soils in tea plantations. The linear regression model between color values and soil organic carbon contents showed it can be used as a rapid, cost-effective method to evaluate content of soil organic matter in Chinese tea plantations.

In order to examine the intensity of surficial sediment resuspension in Lake Taihu, a large shallow lake in eastern China, suspended sediment concentrations (SSCs) were measured on the basis of analysis of water samples collected using an innovative multi-level water sampler. The results show that under calm weather conditions, the SSC is relatively homogenous through the entire water column. However, when strong winds occur, the SSC in the bottom layer is 1–2 orders of magnitude greater than in the surface layer; thus, in this case, the amount of total suspended matter in the water column cannot be estimated using the SSC values of the surface layer alone. Furthermore, the depth of disturbance, or the thickness of the sediment layer that is set in motion by wind-wave induced currents, is of the order of 100 mm.