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ROUTE DEVELOPMENT, ANTIVIRAL STUDIES, FIELD EVALUATION AND TOXICITY OF AN ANTIVIRAL PLANT PROTECTANT NK0238

《农业科学与工程前沿(英文)》 2022年 第9卷 第1期 doi: 10.15302/J-FASE- 2021390

摘要:

It has previously been shown that tryptophan, the biosynthesis precursor of Peganum harmala alkaloids, and its derivatives have anti-TMV activity both in vitro and in vivo. Further exploration of this led to the identification of NK0238 as a highly effective agent for the prevention and control of diseases caused by plant viruses, but the existing routes are unsuitable for its large-scale synthesis. This study optimized a route for two-step synthesis of this virucide candidate via reaction of l-tryptophan with triphosgene to produce l-tryptophan-N-carboxylic anhydride, which then reacts with n-octylamine to give NK0238 at up to 94% yield and nearly 97% HPLC purity. In addition, the route was used for the preparation of NK0238 on a>40 g scale permitting further assessment of its antivirus activity in the greenhouse and field experiments, and toxicity tests. NK0238 exhibited useful antiviral activities against a variety of viruses both in greenhouse and field experiments. The toxicity tests showed that NK0238 was not acutely toxic to birds, fish, honey bees and silkworms. The optimized route provides a solid foundation for its large-scale synthesis and subsequent efficacy and toxicity studies, its excellent activity and safety make NK0238 a promising drug candidate for further development.

 

关键词: antiviral plant protectant / antiviral in the greenhouse / field evaluation / l-trp-NCA / synthesis optimization / toxicity tests    

ROUTE DEVELOPMENT, ANTIVIRAL STUDIES, FIELD EVALUATION AND TOXICITY OF AN ANTIVIRAL PLANT PROTECTANT NK0238

Wentao XU, Hao TIAN, Hongjian SONG, Yuxiu LIU, Yongqiang LI, Qingmin WANG

《农业科学与工程前沿(英文)》   页码 110-119 doi: 10.15302/J-FASE-2021390

摘要: It has previously been shown that tryptophan, the biosynthesis precursor of alkaloids, and its derivatives have anti-TMV activity both and . Further exploration of this led to the identification of NK0238 as a highly effective agent for the prevention and control of diseases caused by plant viruses, but the existing routes are unsuitable for its large-scale synthesis. This study optimized a route for two-step synthesis of this virucide candidate via reaction of L-tryptophan with triphosgene to produce L-tryptophan- -carboxylic anhydride, which then reacts with -octylamine to give NK0238 at up to 94% yield and nearly 97% HPLC purity. In addition, the route was used for the preparation of NK0238 on a > 40 g scale permitting further assessment of its antivirus activity in the greenhouse and field experiments, and toxicity tests. NK0238 exhibited useful antiviral activities against a variety of viruses both in greenhouse and field experiments. The toxicity tests showed that NK0238 was not acutely toxic to birds, fish, honey bees and silkworms. The optimized route provides a solid foundation for its large-scale synthesis and subsequent efficacy and toxicity studies, its excellent activity and safety make NK0238 a promising drug candidate for further development.

关键词: antiviral plant protectant     antiviral in the greenhouse     field evaluation     L-trp-NCA     synthesis optimization     toxicity tests    

Comments on the special issue on forestry of

John L. INNES

《农业科学与工程前沿(英文)》 2017年 第4卷 第4期   页码 502-503 doi: 10.15302/J-FASE-2017189

PD-1/PD-L1 blockade in cervical cancer: current studies and perspectives

Yumeng Wang, Guiling Li

《医学前沿(英文)》 2019年 第13卷 第4期   页码 438-450 doi: 10.1007/s11684-018-0674-4

摘要: Cervical cancer (CC) is the fourth most commonly diagnosed female malignancy and a leading cause of cancer-related mortality worldwide, especially in developing countries. Despite the use of advanced screening and preventive vaccines, more than half of all CC cases are diagnosed at advanced stages, when therapeutic options are extremely limited and side effects are severe. Given these circumstances, new and effective treatments are needed. In recent years, exciting progress has been made in immunotherapies, including the rapid development of immune checkpoint inhibitors. Checkpoint blockades targeting the PD-1/PD-L1 axis have achieved effective clinical responses with acceptable toxicity by suppressing tumor progression and improving survival in several tumor types. In this review, we summarize recent advances in our understanding of the PD-1/PD-L1 signaling pathway, including the expression patterns of PD-1/PD-L1 and potential PD-1/PD-L1-related therapeutic strategies for CC.

关键词: PD-1     PD-L1     immune checkpoint blockade antibody     immunotherapy     cervical cancer    

Gridded usage inventories of chlordane in China

Qiang WANG, Lijuan ZHAO, Xuekun FANG, Jianhua XU, Yifan LI, Yehong SHI, Jianxin HU

《环境科学与工程前沿(英文)》 2013年 第7卷 第1期   页码 10-18 doi: 10.1007/s11783-012-0458-z

摘要: Chlordane (1,2,4,5,6,7,8,8-octachloro-3a,4,7, 7a-tetra-hydro-4,7-methanoindane) is one of organochlorine pesticides (OCPs) which has been listed as one of the persistent organic pollutants (POPs) to be reduced and finally eliminated in the Stockholm Convention on Persistent Organic Pollutants, because of its great persistence, toxicity, bio-accumulation and long-range transport potential. It is critical to create a national chlordane usage inventories for China to compile chlordane emission inventories, which is helpful for carrying out risk assessments and other researches related to chlordane in China. The annual data of chlordane usage was calculated and modified in accordance with the reported annual production of chlordane which was caculated on the basis of the termite distribution, the data of chlordane usage rate and the annual new construction area (NCA). With the help of Geographic Information System, the usage data of this NCA were allocated to a grid system then, with a 1/4° longitude by 1/6° latitude resolution and a size for each grid cell of approximately 25 km by 25 km. Between 1988 and 2008, the total usage of chlordane in China was 2745 t, accounting for approximately 80% of the production in the same period. Zhejiang Province was the largest consumer of chlordane in China, whose usage adds up to 980 t, greatly exceeding other provinces/regions, followed by Jiangsu Province (534 t) and Sichuan Province (428 t). The region with the least usage of chlordane was Beijing. Provinces of Guizhou, Henan and Hebei did not use any chlordane, even though termites had occurred in these provinces. Gridded usage inventories showed that the intensive use of chlordane was concentrated in the south-east part of China, Yangtze River Delta and Pearl River Delta in particular. The satisfaction of the inventories was supported by the consistence between the estimated data of annual usage and the reported annual production of chlordane, and by the consistence between distribution pattern of chlordane’s usage and ambient air concentration.

关键词: chlordane     inventories     termites     China     new construction area (NCA)    

In memory of Perry L. McCarty, seminal founder of Environmental Biotechnology

《环境科学与工程前沿(英文)》 2023年 第17卷 第10期 doi: 10.1007/s11783-023-1730-0

Shear design of high strength concrete prestressed girders

Emad L. LABIB,Hemant B. DHONDE,Thomas T. C. HSU,Y. L. MO

《结构与土木工程前沿(英文)》 2014年 第8卷 第4期   页码 373-387 doi: 10.1007/s11709-014-0087-7

摘要: Normal strength prestressed concrete I-girders are commonly used as the primary superstructure components in highway bridges. However, shear design guidelines for high strength PC girders are not available in the current structural codes. Recently, ten 7.62 m (25 feet) long girders made with high strength concrete were designed, cast, and tested at the University of Houston (UH) to study the ultimate shear strength and the shear concrete contribution ( ) as a function of concrete strength ( ). A simple semi-empirical set of equations was developed based on the test results to predict the ultimate shear strength of prestressed concrete I-girders. The UH-developed set of equations is a function of concrete strength ( ), web area ( ), shear span to effective depth ratio ( / ), and percentage of transverse steel ( ). The proposed UH-Method was found to accurately predict the ultimate shear strength of PC girders with concrete strength up to 117 MPa (17000 psi) ensuring satisfactory ductility. The UH-Method was found to be not as overly conservative as the ACI-318 (2011) code provisions, and also not to overestimate the ultimate shear strength of high strength PC girders as the AASHTO LRFD (2010) code provisions. Moreover, the proposed UH-Method was found fairly accurate and not exceedingly conservative in predicting the concrete contribution to shear for concrete strength up to 117 MPa (17000 psi).

关键词: shear design     high strength concrete     prestressed girders     full-scale tests    

Deeply missing my career idol and role model ― Professor Perry L. McCarty

《环境科学与工程前沿(英文)》 2023年 第17卷 第9期 doi: 10.1007/s11783-023-1717-x

Urban watershed management under rapid urbanization

Pengfei DU, Haifeng JIA, Shaw L. YU

《环境科学与工程前沿(英文)》 2012年 第6卷 第5期   页码 595-595 doi: 10.1007/s11783-012-0452-5

Recombinant aspartate aminotransferase-catalyzed synthesis of L-4-fluorophenylalanine

CHEN Meijuan, JIA Honghua, CHEN Yongsheng, JIANG Min, WEI Ping

《化学科学与工程前沿(英文)》 2008年 第2卷 第2期   页码 220-223 doi: 10.1007/s11705-008-0041-0

摘要: L-4-Fluorophenylalanine (FPhe) was prepared from 4-fluorophenylpyruvate (FPPA) catalyzed by aspartate aminotransferase (Asp-AT) of the recombinant BL21-pET/aspC. After 12 h enzymatic reaction, the FPPA conversion was over 90% and the yield of FPhe could be above 85% under the following optimal conditions: 37°C, pH value range of 5.0–8.0, 5.5 mass ratio of cell to FPPA, 0.6% (w/v) of Tween 80, 7.08 g/L FPPA, and 1.6 of molar ratio of L-Asp to FPPA.

关键词: L-4-Fluorophenylalanine     Asp-AT     aspartate aminotransferase     4-fluorophenylpyruvate     FPPA    

Effects of different doses of cadmium on secondary metabolites and gene expression in Artemisia annua L.

null

《医学前沿(英文)》 2017年 第11卷 第1期   页码 137-146 doi: 10.1007/s11684-016-0486-3

摘要:

This study aims to elucidate the underlying molecular mechanisms of artemisinin accumulation induced by cadmium (Cd). The effects of different Cd concentrations (0, 20, 60, and 120 μmol/L) on the biosynthesis of Artemisia annua L. were examined. Intermediate and end products were quantified by HPLC-ESI-MS/MS analysis. The expression of key biosynthesis enzymes was also determined by qRT-PCR. The results showed that the application of treatment with 60 and 120 μmol/L Cd for 3 days significantly improved the biosynthesis of artemisinic acid, arteannuin B, and artemisinin. The concentrations of artemisinic acid, arteannuin B, and artemisinin in the 120 μmol/L Cd-treated group were 2.26, 102.08, and 33.63 times higher than those in the control group, respectively. The concentrations of arteannuin B and artemisinin in 60 μmol/L Cd-treated leaves were 61.10 and 26.40 times higher than those in the control group, respectively. The relative expression levels of HMGRFPSADSCYP71AV1DBR2ALDH1, and DXR were up-regulated in the 120 μmol/L Cd-treated group because of increased contents of artemisinic metabolites after 3 days of treatment. Hence, appropriate doses of Cd can increase the concentrations of artemisinic metabolites at a certain time point by up-regulating the relative expression levels of key enzyme genes involved in artemisinin biosynthesis.

关键词: Cd     secondary metabolites     gene expressions     Artemisia annua L.    

Reactive extraction for preparation of hydrogen peroxide under pressure

CHENG Yongxi, LI Hongtao, WANG Li, LÜ Shuxiang

《化学科学与工程前沿(英文)》 2008年 第2卷 第3期   页码 335-340 doi: 10.1007/s11705-008-0042-z

摘要: The preparation of hydrogen peroxide from anthrahydroquinone by reactive extraction was investigated. The integration process of oxidation of anthrahydroquinone by air and extraction of hydrogen peroxide from the organic phase with water was carried out in a sieve plate column under pressure. The conversion of anthrahydroquinone increased with increasing pressure resulting in an increase of hydrogen peroxide concentration in the aqueous phase. However, no change in extraction efficiency of hydrogen peroxide was observed. A mathematical model for gas-liquid-liquid reactive extraction was established. In the model, the effects of pressure and gas superficial velocity on reaction were considered. With increasing gas superficial velocity, the conversion of anthrahydroquinone increased, and the fraction of hydrogen peroxide extracted reached a plateau with a maximum of 72.94%. However, both the conversion of anthrahydroquinone and the fraction of hydrogen peroxide extracted decreased with increasing organic phase superficial velocity.

地下工程的发展提升现代生活质量

Raymond L. Sterling

《工程(英文)》 2017年 第3卷 第6期   页码 780-781 doi: 10.1016/j.eng.2017.12.006

Size-controlled green synthesis of silver nanoparticles assisted by L-cysteine

Wenchao Zhang,Lin Zhang,Yan Sun

《化学科学与工程前沿(英文)》 2015年 第9卷 第4期   页码 494-500 doi: 10.1007/s11705-015-1527-1

摘要: A green and size-controlled synthesis of silver nanoparticles (Ag NPs) in aqueous solution with the assistance of L-cysteine is presented. The size of Ag NPs decreases with the increase of L-cysteine concentration, and thus can be controlled by adjusting L-cysteine concentration. TEM analysis shows that Ag NPs with an average size of 3 nm can be produced in the presence of 1.0 mmol/L L-cysteine, about one sixth of the size of Ag NPs obtained in the absence of L-cysteine (17 nm). The as-synthesized silver colloidal solution is stable and can be stored at room temperature for at least two months without any precipitation. This L-cysteine assisted method is simple, feasible and efficient, and would facilitate the production and application of Ag NPs.

关键词: nanoparticles     silver     L-cysteine     size distribution     synthesis    

Quality Function Deployment Implementation in Construction: A Systematic Literature Review

Cudney,William L. Gillis

《工程管理前沿(英文)》 2016年 第3卷 第3期   页码 224-230 doi: 10.15302/J-FEM-2016036

摘要: The construction of new buildings represents a significant investment. The goal of new building construction is to maximize value and minimize cost while staying on time and within budget. Translating customer requirements into engineering terms for new construction design is vital for a construction project to be successful. Quality function deployment has been successfully used in product development to capture the voice of the customer and translate it into engineering characteristics. Quality function deployment then carries these parameters into production and service to ensure the voice of the customer is being met with the final product. The house of quality, a tool within quality function deployment, can provide a means for comparison of owner’s project requirements and the proposed design, along with identifying how the design decisions impact meeting customer requirements and green building requirements. Quality function deployment can effectively link the project phases through design and construction and into operations and maintenance to ensure the owner’s project requirements are met with the final building. This research identifies and categorizes studies of quality function deployment applications in construction. The research method used is a systematic literature review from databases related to quality function deployment in the construction industry published in the periodicals through 2016. The principal findings of implementations, practices, and integrated approaches are then summarized. This article intends to propel further research of quality function deployment in the construction sector.

关键词: construction     engineering management     quality function deployment     systematic review    

标题 作者 时间 类型 操作

ROUTE DEVELOPMENT, ANTIVIRAL STUDIES, FIELD EVALUATION AND TOXICITY OF AN ANTIVIRAL PLANT PROTECTANT NK0238

期刊论文

ROUTE DEVELOPMENT, ANTIVIRAL STUDIES, FIELD EVALUATION AND TOXICITY OF AN ANTIVIRAL PLANT PROTECTANT NK0238

Wentao XU, Hao TIAN, Hongjian SONG, Yuxiu LIU, Yongqiang LI, Qingmin WANG

期刊论文

Comments on the special issue on forestry of

John L. INNES

期刊论文

PD-1/PD-L1 blockade in cervical cancer: current studies and perspectives

Yumeng Wang, Guiling Li

期刊论文

Gridded usage inventories of chlordane in China

Qiang WANG, Lijuan ZHAO, Xuekun FANG, Jianhua XU, Yifan LI, Yehong SHI, Jianxin HU

期刊论文

In memory of Perry L. McCarty, seminal founder of Environmental Biotechnology

期刊论文

Shear design of high strength concrete prestressed girders

Emad L. LABIB,Hemant B. DHONDE,Thomas T. C. HSU,Y. L. MO

期刊论文

Deeply missing my career idol and role model ― Professor Perry L. McCarty

期刊论文

Urban watershed management under rapid urbanization

Pengfei DU, Haifeng JIA, Shaw L. YU

期刊论文

Recombinant aspartate aminotransferase-catalyzed synthesis of L-4-fluorophenylalanine

CHEN Meijuan, JIA Honghua, CHEN Yongsheng, JIANG Min, WEI Ping

期刊论文

Effects of different doses of cadmium on secondary metabolites and gene expression in Artemisia annua L.

null

期刊论文

Reactive extraction for preparation of hydrogen peroxide under pressure

CHENG Yongxi, LI Hongtao, WANG Li, LÜ Shuxiang

期刊论文

地下工程的发展提升现代生活质量

Raymond L. Sterling

期刊论文

Size-controlled green synthesis of silver nanoparticles assisted by L-cysteine

Wenchao Zhang,Lin Zhang,Yan Sun

期刊论文

Quality Function Deployment Implementation in Construction: A Systematic Literature Review

Cudney,William L. Gillis

期刊论文