Novel collector lead(II)-benzohydroxamic acid (Pb(II)-BHA) complexes in aqueous solution were characterized by using experimental approaches, including Ultraviolet-visible (UV-Vis) spectroscopy and electrospray ionization–mass spectrometry (ESI-MS), as well as first-principle density functional theory (DFT) calculations with consideration for solvation effects. The Job plot delineated that a single coordinated Pb(BHA)⁺ should be formed first, and the higher coordination number complexes can be formed subsequently. Moreover, the Pb(II)-BHA species can aggregate with each other to form complicated structures, such as Pb(BHA)₂ or highly complicated complexes. ESI-MS results validated the existence of Pb-(BHA)_n=1,2 under different solution pH values. Further, the first-principles calculations suggested that Pb(BHA)⁺ should be the most stable structure, and the Pb atom in Pb(BHA)⁺ will act as an active site to attack nucleophiles. These findings are meaningful to further illustrate the adsorption mechanism of Pb(II)-BHA complexes in mineral processing.

Ischemia stroke is one of a clinically common cerebrovascular disease. And Inhibition of brain tissue ischemia and reperfusion-induced damage, especially apoptosis, has an irreplaceable protective effect on ischemic nerves, and has special significance for the treatment of patients after treatment. However, the development of neuroprotective drugs still has certain challenges. Radix scrophulariae as a valuable medicine, has been discovered to has neuroprotective effects. Our researches initially proved that Radix scrophulariae aqueous extract (RSAE) exerting a neuroprotective effects on cerebral ischemia and reperfusion (I/R) injury in oxygen glucose deprivation and reperfusion (OGD/R)-induced PC12 cells and middle cerebral artery occlusion/reperfusion (MCAO/R) model mice, were associated with attenuation of infarct volume, brain water content, nitric oxide (NO) and malondialdehyde (MDA), inhibiting I/R-induced damage by reducing the levels of LDH release, improving anti-oxidant capacity by upregulating the SOD, GSH-Px and CAT activity, stabilizing mitochondrial membrane potential, reducing neuronal apoptosis, necrosis and neuronal loss by regulating the expression of anti-apoptotic BCL-2and pro-apoptotic protein Bax, and elucidating downregulate the phosphorylation levels of MAPK pathways. Our findings may elaborate the neuroprotective effects and potential mechanisms of RSAE on focal cerebral I/R injury in mice. Since, Radix scrophulariae, as a potential neuroprotective natural plant, has originally been identified to, our results may offer directions and clues for discovering new active compounds or drugs for treatment of ischemic stroke, which allows us to discover many new natural active chemicals by chemical separation and identification, and provide new insights into therapeutic targets in stroke patients.

African swine fever virus (ASFV) is a large double stranded DNA arbovirus that is highly contagious and seriously endangers the lives of domestic and wild pigs. In the past decade, African swine fever (ASF) has spread in many countries in the Caucasus, Russian Federation, Eastern Europe and Asia, causing significant losses to the pig industry. At present, there is a lack of effective vaccine and treatment for ASF. Therefore, the rapid and accurate detection is crucial for ASF prevention and control. In this study, we have developed a portable lateral flow strip (LFS) detection method mediated by recombinase polymerase amplification (RPA) and DNA enzyme (LwCas13a), which is performed at 37 ℃ and visualized by eyes without the need for complex instruments. This RPA-LwCas13a-LFS is based on the ASFV structural protein p17 gene (D117L), with a detection sensitivity up to 2 gene copies. This method is highly specific and has no cross reactivity to 7 other pig viruses. In the detection of 33 clinical samples, the p17 (D117L) RPA-LwCas13a-LFS had 100% coincidence with conventional quantitative PCR (qPCR). These findings demonstrate the potential of this simple, rapid, sensitive, and specific ASFV detection method for on-site ASFV detection.