ABSTRACT
The detection of volatile amines is necessary due to the serious toxicity hazards they pose to human skin, respiratory systems, and nervous systems. However, traditional amines detection methods require bulky equipment, high costs, and complex measurements. Herein, we report a new simple, rapid, convenient, and visual method for the detection of volatile amines based on the gas-solid reactions of tetrachloro-p-benzoquinone (TCBQ) and volatile amines. The gas-solid reactions of TCBQ with a variety of volatile amines showed a visually distinct color in a time-dependent manner. Moreover, TCBQ can be easily fabricated into simple and flexible rapid test strips for detecting and distinguishing n-propylamine from other volatile amines, including ethylamine, n-butyamine, n-pentamine, n-butyamine and dimethylamine, in less than 3 s without any equipment assistance.
ABSTRACT
Ticks are specialized ectoparasites that feed on blood, causing physical harm to the host and facilitating pathogen transmission. The genus Haemaphysalis contains vectors for numerous infectious agents. These agents cause various diseases in humans and animals. Mitochondrial genome sequences serve as reliable molecular markers, forming a crucial basis for evolutionary analyses, studying species origins, and exploring molecular phylogeny. We extracted mitochondrial genome from the enriched mitochondria of Haemaphysalis tibetensis and obtained a 14,714-bp sequence. The mitochondrial genome consists of 13 protein-coding genes (PCGs), two ribosomal RNA, 22 transfer RNAs (tRNAs), and two control regions. The nucleotide composition of H. tibetensis mitochondrial genome was 38.38 % for A, 9.61 % for G, 39.32 % for T, and 12.69 % for C. The A + T content of H. tibetensis mitochondrial genome was 77.7 %, significantly higher than the G + C content. The repeat units of H. tibetensis exhibited two identical repeat units of 33 bp in length, positioned downstream of nad1 and rrnL genes. Furthermore, phylogenetic analyses based on the 13 PCGs indicated that Haemaphysalis tibetensis (subgenus Allophysalis) formed a monophyletic clade with Haemaphysalis nepalensis (subgenus Herpetobia) and Haemaphysalis danieli (subgenus Allophysalis). Although the species Haemaphysalis inermis, Haemaphysalis kitaokai, Haemaphysalis kolonini, and Haemaphysalis colasbelcouri belong to the subgenus Alloceraea, which were morphologically primitive hemaphysalines just like H. tibetensis, these four tick species cannot form a single clade with H. tibetensis. In this study, the whole mitochondrial genome sequence of H. tibetensis from Tibet was obtained, which enriched the mitochondrial genome data of ticks and provided genetic markers to study the population heredity and molecular evolution of the genus Haemaphysalis.
Subject(s)
Genome, Mitochondrial , Ixodidae , Animals , Humans , Phylogeny , RNA, Ribosomal/genetics , TibetABSTRACT
As is well documented, Alzheimer's disease (AD) is the most prevalent neurodegenerative disease. Meanwhile, Schisandra polysaccharide (SCP) has been reported to exert a protective effect on the nervous system and can regulate metabolic disorders in AD-like symptoms of amyloid ß-peptide (Aß) 25-35-induced rats. Nevertheless, the underlying mechanisms and metabolic markers for the diagnosis of AD are yet to be determined. This study aimed to explore the neuroprotective effect and potential mechanism of action of SCP in AD-like symptoms of Aß25-35-induced rats by combining pharmacodynamics, metabolomics, and lipidomics. The pharmacodynamic results revealed that SCP significantly improved the spatial learning and long-term memory function and the morphology of neurons in the hippocampal CA1 region, alleviated inflammatory damage and oxidative stress, inhibited the activation of microglia and astrocytes, and increased the proportion of mature neurons of AD-like symptoms of Aß25-35-induced rats. The results of hippocampal metabolomics and serum lipidomics showed 46 and 48 potential biomarkers were identified for the SCP treatment of AD, respectively. The involved pathways principally comprised lipid metabolism, amino acid metabolism, and energy metabolism. This study elucidates the neuroprotective effect of SCP in AD and its mechanism from the perspective of metabolomics and lipidomics and provides a theoretical basis for the therapeutic effect of SCP in AD.
ABSTRACT
Electrochemical reduction of carbon dioxide (CO2) to value-added carbon products is a promising approach to reduce CO2 levels and mitigate the energy crisis. However, poor product selectivity is still a major obstacle to the development of CO2 reduction. Here we demonstrate exclusive Ni-N4 sites through a topo-chemical transformation strategy, bringing unprecedentedly high activity and selectivity for CO2 reduction. Topo-chemical transformation by carbon layer coating successfully ensures preservation of the Ni-N4 structure to a maximum extent and avoids the agglomeration of Ni atoms to particles, providing abundant active sites for the catalytic reaction. The Ni-N4 structure exhibits excellent activity for electrochemical reduction of CO2 with particularly high selectivity, achieving high faradaic efficiency over 90% for CO in the potential range from -0.5 to -0.9 V and gives a maximum faradaic efficiency of 99% at -0.81 V with a current density of 28.6 mA cm-2. We anticipate exclusive catalytic sites will shed new light on the design of high-efficiency electrocatalysts for CO2 reduction.
