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961.
The continuous emergence of severe acute respiratory coronavirus 2 (SARS-CoV-2) variants and the increasing number of breakthrough infection cases among vaccinated people support the urgent need for research and development of antiviral drugs. Viral entry is an intriguing target for antiviral drug development. We found that diltiazem, a blocker of the L-type calcium channel Cav1.2 pore-forming subunit (Cav1.2 α1c) and an FDA-approved drug, inhibits the binding and internalization of SARS-CoV-2, and decreases SARS-CoV-2 infection in cells and mouse lung. Cav1.2 α1c interacts with SARS-CoV-2 spike protein and ACE2, and affects the attachment and internalization of SARS-CoV-2. Our finding suggests that diltiazem has potential as a drug against SARS-CoV-2 infection and that Cav1.2 α1c is a promising target for antiviral drug development for COVID-19.  相似文献   
962.
A human papillomavirus type 16 E7 DNA vaccine with the open reading frame encoding mutations in two zinc-binding motifs expressed a rapidly degraded E7 protein. This vaccine induced a significantly stronger E7-specific cytotoxic T-lymphocyte response and better tumor protection in mice than did a wild-type E7 DNA vaccine expressing a stable E7 protein.  相似文献   
963.
Megalin is a large endocytic receptor expressed at the apical surface of several absorptive epithelia. It binds multiple ligands including apolipoproteins, vitamin and hormone carrier proteins and signaling molecules such as parathyroid hormone and the morphogen sonic hedgehog. An important characteristic of megalin is its high endocytic activity, which is mediated by tyrosine-based endocytic motifs within the receptor's cytoplasmic tail. This domain also harbors several putative consensus phosphorylation motifs for protein kinase (PK) C and casein kinase-II and one consensus motif for PKA and glycogen synthase kinase-3 (GSK3). Here we report that the cytoplasmic domain of megalin is constitutively phosphorylated depending on the integrity of a PPPSP motif, a putative GSK3 site, with a minor participation of the other phosphorylation motifs. Mutation of the serine residue within the PPPSP motif as well as blocking GSK3 activity, with two different inhibitors, significantly decreased the phosphorylation levels of the receptor. Both the megalin PPPAP mutant and the underphosphorylated wild-type receptor, by inhibition of GSK3 activity, were more expressed at the cell surface and more efficiently recycled, but they were not inhibited in their initial endocytosis rates. Altogether, these results show that the PPPSP motif and the GSK3 activity are critical to allow megalin phosphorylation and also negatively regulate the receptor's recycling.  相似文献   
964.
A high throughput off-line microElution 96-well solid phase extraction (SPE) followed by liquid chromatography with tandem mass spectrometry (LC/MS/MS) quantification for the determination of N-acetyl retigabine in dog plasma has been developed and validated. The method involves the use of microElution 96-well SPE for the simultaneous extraction of N-acetyl retigabine and rapid removal of its N-glucuronide metabolite that has shown to be problematic due to its instability using other clean-up methods. The microElution SPE technology eliminates the need for post-extraction solvent evaporation and greatly reduces sample preparation time consequently improving assay efficiency.  相似文献   
965.
966.
Wang  H. J.  Bu  M.  Wang  J.  Liu  L.  Zhang  S. 《Russian Journal of Bioorganic Chemistry》2019,45(6):585-590
Russian Journal of Bioorganic Chemistry - Seven new steroidal 5α,8α-endoperoxide derivatives with C-17 aromatic hydrazone side chain were synthesized. Structures of the synthesized...  相似文献   
967.
Aims Tree species richness has been reported to have positive effects on aboveground biomass and productivity, but little is known about its effects on soil organic carbon (SOC) accumulation.  相似文献   
968.
Yang  Qi  Wu  Bo  Yao  Fubing  He  Li  Chen  Fei  Ma  Yinghao  Shu  Xiaoyu  Hou  Kunjie  Wang  Dongbo  Li  Xiaoming 《Reviews in Environmental Science and Biotechnology》2019,18(4):771-793
Reviews in Environmental Science and Bio/Technology - Anaerobic digestion is a versatile biotechnology to treat waste activated sludge (WAS), the main by-products of biological wastewater...  相似文献   
969.
A symmetric solid‐state battery based on organic porous electrodes is fabricated using scalable spray‐printing. The active electrode material is based on a textile dye (disperse blue 134 anthraquinone) and is capable of forming divalent cations and anions in oxidation and reduction processes. The resulting molecule can be used in both negative and positive electrode reactions. After spray printing an inter‐connected pore honeycomb electrode, a solid‐state electrolyte (σLi: × 10?4 S cm?1) based on a polymeric ionic liquid is spray‐printed as a second layer and infiltrated through the porous electrodes. A symmetric all‐organic battery is then formed with the addition of another identical set of electrode and electrolyte layers. Both density functional theory calculations and charge‐discharge profiles show that the potentials for the negative and positive electrode reactions are amongst the lowest (≈2.0 V vs Li) and the highest (≈3.5 V vs Li), respectively, for quinone‐type molecules. Over the C‐rate range 0.2 to 5 C, the battery has a discharge cell voltage of more than 1 V even up to 250 charge‐discharge cycles and capacities are in the range 50–80 mA h g?1 at 0.5 C.  相似文献   
970.
刘莹莹  卜宁  卢元 《生物工程学报》2019,35(12):2269-2283
无细胞合成生物系统,能够在体外完成生命转录翻译过程,因体系灵活开放、便于控制、表达周期短、高耐受性等特点,可表达细胞系统难以表达的蛋白质。随着无细胞生物传感和体系冻干技术的不断发展,其在医药健康领域的应用不断拓展。本文综述了无细胞合成生物学在按需生物医药合成和便携式医疗检测等医药健康领域的研究进展,该体系的进一步发展有潜力实现更复杂后修饰蛋白质药物的合成、可丰富无细胞生物传感器类型并提高其灵敏性。无细胞合成生物学作为新兴工程策略,未来必将更好地应用于高通量医药蛋白质筛选、新型病原体的检测等医药健康领域。  相似文献   
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