Identifying the Species of Seeds in Traditional Chinese Medicine Using DNA Barcoding

Seed is not only the main reproductive organ of most of herbal plants but also an important part of Traditional Chinese Medicine (TCM). Seed TCMs possess important medicinal properties and have been widely used as components of pharmaceutical products. In parallel with the increasing popularity and accessibility of seeds as medicinal products in recent years, numerous substitutes and adulterants have also appeared on the market. Due to the small volume and similar appearances of many seed TCMs, they are very difficult to accurately identify the constituent plant species through organoleptic methods. Usage of the wrong herb may be ineffective or may worsen the condition and even cause death. Correct identification of seed herbal medicines is therefore essential for their safe use. Here, we acquired 177 ITS2 sequences and 15 psbA-trnH sequences from 51 kinds of seed TCMs belonging to 64 species that have been described in the Chinese Pharmacopoeia. Tree-building analysis showed that the ITS2 sequences of 48 seed TCMs can be differentiated from each other, and they formed distinct, non-overlapping groups in the maximum-likelihood tree. Furthermore, all of the sequences acquired in this study have been submitted to the public DNA barcoding system for herbal medicine, and this integrated database was used to identify 400 seed TCM samples purchased from medicinal markets, drug stores, and the Internet, enabling the identification of 7.5% of the samples as containing non-declared species. This study provides a brief operating procedure for the identification of seed TCMs found in herbal medicine. In the future, researchers and traditional herbal medicine enterprises can use this system to test their herbal materials

Infection of inbred BALB/c and C57BL/6 and outbred Institute of Cancer Research mice with the emerging H7N9 avian influenza virus

A new avian-origin influenza virus A (H7N9) recently crossed the species barrier and infected humans; therefore, there is an urgent need to establish mammalian animal models for studying the pathogenic mechanism of this strain and the immunological response. In this study, we attempted to develop mouse models of H7N9 infection because mice are traditionally the most convenient models for studying influenza viruses. We showed that the novel A (H7N9) virus isolated from a patient could infect inbred BALB/c and C57BL/6 mice as well as outbred Institute of Cancer Research (ICR) mice. The amount of bodyweight lost showed differences at 7 days post infection (d.p.i.) (BALB/c mice 30%, C57BL/6 and ICR mice approximately 20%), and the lung indexes were increased both at 3 d.p.i. and at 7 d.p.i.. Immunohistochemistry demonstrated the existence of the H7N9 viruses in the lungs of the infected mice, and these findings were verified by quantitative real-time polymerase chain reaction (RT-PCR) and 50% tissue culture infectious dose (TCID50) detection at 3 d.p.i. and 7 d.p.i.. Histopathological changes occurred in the infected lungs, including pulmonary interstitial inflammatory lesions, pulmonary oedema and haemorrhages. Furthermore, because the most clinically severe cases were in elderly patients, we analysed the H7N9 infections in both young and old ICR mice. The old ICR mice showed more severe infections with more bodyweight lost and a higher lung index than the young ICR mice. Compared with the young ICR mice, the old mice showed a delayed clearance of the H7N9 virus and higher inflammation in the lungs. Thus, old ICR mice could partially mimic the more severe illness in elderly patients. </p

Functional ingredients of Folium Nelumbinis against amyloid-β toxicity in C. elegans: The bioactive compounds screened and the molecular mechanism explored

Alzheimer’s disease (AD) is an insidious, neurodegenerative disease that no drug can prevent or cure. Folium Nelumbinis (FN) has rich functional components with neuroprotective effects. This research explored the FN chemical profile and the neuroprotective effect in vivo. Studies on the safety assessment of FN extract, effects on amyloid-β (Aβ) aggregation, oxidative stress, and acetylcholinesterase (AChE) activity were performed in Caenorhabditis elegans. Results revealed that the FN extract could delay paralysis, reduce Aβ deposition, lower oxidative stress, attenuate AChE activity, and regulate genes and proteins related to Aβ toxicity, which suggested that it exerts a dual targeting effect on Aβ and AChE simultaneously. Additionally, seven individual components from FNE were screened out with affinity ultrafiltration mass spectrum combined with molecular docking. The underlying mechanisms might be relevant to the DAF-16/FOXO signaling pathway and ACE1/ACE2 axis. In conclusion, FN is valuable in health promotion and AD prevention

Study on the Optimized Muffler with Function of PM Filtration for Non-Road Diesel Engines

With a high thermal efficiency, high reliability and good fuel economy, diesel engines have been widely used. However, with the increasingly stringent standards regarding non-road diesel engine emissions, diesel engines can hardly satisfy the particle emission requirements through internal purification alone. To reduce the particle emission and noise levels of the non-road diesel engine R180, this paper optimized the original muffler, and endowed the muffler with a particulate matter (PM) filtering function to improve the muffling. This study first proposed stainless steel fiber as the filtering medium as it is inexpensive and accessible; a bench experiment was conducted to verify the particle filtration performance and its effect on the overall engine performance. Then, the structure of the existing muffler in non-road diesel engines R180 was optimized, and the stainless steel fiber filtering was integrated. The internal flow field of the optimized muffler was obtained in the computational fluid dynamics software FLUENT, and the acoustic and filtration performance was studied. The experimental and simulation results indicated that the optimized muffler could achieve both particle filtration and noise reduction

A novel recombinant cccDNA-based mouse model with long term maintenance of rcccDNA and antigenemia

The covalently closed circular DNA (cccDNA) of hepatitis B virus (HBV) is critical for viral persistence in vivo. The lack of reliable, characterized and convenient small animal models for studying cccDNA persistence has long been a bottleneck for basic and translational research on HBV cure. A mouse model that can maintain intrahepatic cccDNA is urgently needed. Through combining the Cre/loxP-mediated recombination and adeno-associated virus (AAV) vector delivery strategy, we establish a novel recombinant cccDNA (rcccDNA) mouse model. AAV-rcccDNA mice supported long-term maintenance of intrahepatic rcccDNA which could be easily detected by Southern blotting within 30 weeks after transduction. Quantitative PCR could detect the rcccDNA signal throughout the experiment duration (&gt;51 weeks). Furthermore, rcccDNA supported persistent serum antigenemia (&gt;72 weeks) and intrahepatic HBsAg and HBcAg expression (&gt;51 weeks). Flow cytometry analysis and single-cell RNA sequencing showed that AAV-rcccDNA mice displayed a compromised CD8+ T cell response. Meanwhile, minimal intrahepatic inflammation and fibrosis were observed. Furthermore, three anti-HBV compounds, AKEX0007, a post-transcriptional inhibitor, Bay 41-4109, a capsid allosteric modulator, and Entecavir were assessed in this AAV-rcccDNA mouse model. The changes of viral markers by these drugs were consistent with their mode of action although neither of them diminished the level of rcccDNA. This mouse model recapitulated the immune tolerant state of HBV infection with long term maintenance of cccDNA and antigenemia, which will provide a suitable platform for studying cccDNA persistence and developing intervention strategies that would eventually break the tolerance and clear the virus.</p