ABSTRACT
Arnebiae Radix (dried root of Arnebia euchroma (Royle) Johnst.) is a traditional Chinese medicine (TCM) used to treat macular eruptions, measles, sore throat, carbuncles, burns, skin ulcers, and inflammations. The Arnebiae Radix extract can exert anti-breast cancer effects through various mechanisms of action. This study aimed to rapidly screen potential estrogen receptor (estrogen receptor α and estrogen receptor ß) ligands from the Arnebiae Radix extract. In this study, an analytical method based on affinity ultrafiltration coupled with UHPLC-Q-Exactive Orbitrap mass spectrometry was established for rapidly screening and identifying estrogen receptor ligands. Then, bindings of the components to the active site of estrogen receptor (estrogen receptor α and estrogen receptor ß) were investigated via molecular docking. Moreover, surface plasmon resonance (SPR) experiments with six compounds were performed to verify the affinity. As a result, a total of 21 ligands were screened from Arnebiae Radix using affinity ultrafiltration. Among them, 14 and 10 compounds from Arnebiae Radix showed affinity with estrogen receptor α and estrogen receptor ß, respectively. All of those ligands could have a good affinity for the multiple amino acid residues of the estrogen receptor based on molecular docking. In addition, six compounds display the great affinity by SPR. The method established in the study could be used to rapidly screen estrogen receptor ligands in Traditional Chinese medicine. The results demonstrated that the affinity ultrafiltration-UHPLC-Q-Exactive Orbitrap mass spectrometry method not only aids in the interpretation of the potential bioactive components and possible mechanisms of action of Arnebiae Radix but also provides a further effective basis for the quality control of this valuable herb medicine.
ABSTRACT
An easy fabrication method comprising a slit die extrusion-hot stretch-quench process was used to make carbon nanotubes (CNTs) filled with anisotropically conductive polymer composite (ACPC). CNTs were first premixed with polycarbonate (PC) by coagulation and then melt mixed with polyethylene (PE). During extrusion, the CNT/PC/PE composite was subjected to hot stretching to make the CNT/PC phase form in situ an oriented conductive fibril assembly in the PE matrix. Finally the aligned CNT/PC short fibrils were quenched to preserve their structure. The resultant CNT/PC/PE composite exhibited strong anisotropy in conductivity. This method has the advantages of giving a highly oriented structure with good control of electrical anisotropy as well as the ability to be fabricated in a high rate manner. Temperature-resistivity behavior was investigated by observing the resistivity during isothermal treatment (IT) as well as nonisothermal treatment (NIT). Percolation behavior was seen in the isolated direction during the first IT at 180 degrees C. This was a result of a disordering-induced conductive network. In addition, the positive temperature coefficient (PTC) effect attenuated with IT duration. This was seen in contrast to the remaining negative temperature coefficient (NTC). The unique evolution of PTC and NTC effects originated from the ACPC's special conductive network. It can be seen that this is composed of the originally connected "intrinsic pathway" and isolated "potential pathway".
