An Artificial Enzyme for Asymmetric Nitrocyclopropanation of α,β-Unsaturated Aldehydes-Design and Evolution.

The introduction of an abiological catalytic group into the binding pocket of a protein host allows for the expansion of enzyme chemistries. Here, we report the generation of an artificial enzyme by genetic encoding of a non-canonical amino acid that contains a secondary amine side chain. The non-canonical amino acid and the binding pocket function synergistically to catalyze the asymmetric nitrocyclopropanation of α,β-unsaturated aldehydes by the iminium activation mechanism.

Extraction and characterization of anti-virus anthraquinones from Nicotiana tabacum-derived Aspergillus oryzae YNCA1220.

In this study, seven novel anthraquinones (1-7) and four described anthraquinones (8-11) were purified from Nicotiana tabacum-derived Aspergillus oryzae YNCA1220. It is worth noting that only analogs of 4 and 5 have been reported as natural products to date, while the nuclei of compounds 1-3, 6 and 7 were isolated for the first time in nature. Among them, compounds 1-3 bear an unusual anthra[2,3-b]furan-9,10-dione nucleus, 4 and 5 possess a rare 3-methyl-1H-pyrrol-2-yl substituent, and 6 and 7 are new framework anthraquinones bearing a 6-methyl-1,7-dihydro-2H-azepin-2-one ring.

The anti-TMV potency of the tobacco-derived fungus Aspergillus versicolor and its active alkaloids, as anti-TMV activity inhibitors.

Nicotiana tabacum (tobacco) has attracted interest as one of the most economically important industrial crops widely cultivated in China, whose dried leaves are popularly consumed medicinally and recreationally by human societies. In this study, five undescribed alkaloids derivatives, isoaspergillines A-E, together with eight known alkaloids, notoamide D, (1R,4S)-4-benzyl-1-isopropyl-2,4-dihydro-1H-pyrazino-[2,1-b]quinazoline-3,6-dione, protuboxepin K, notoamide C, notoamide M, deoxybrevianamide E, cyclo (D-Pro-L-Trp), and versicolamide B, were obtained from the culture of the Nicotiana tabacum-derived fungus Aspergillus versicolor. Their structures were mainly elucidated through comprehensive analyses of spectroscopic data.

Isoindolin-1-ones from the stems of Nicotiana tabacum and their antiviral activities.

In previous studies, several isoindolin-1-one analogs that exhibited significant anti-tobacco mosaic virus (anti-TMV) activities were isolated from Nicotiana tabacum. Since gene-editing mutants provide a new sample for the discovery of active metabolites, we focused on the stems of YN-18-23 (a mutant N. tabacum for gene editing with the alkaloid metabolic pathway cultivated by Yunnan Tobacco Company), which led to the isolation of four new (1-4) and four known (5-8) isoindolin-1-ones.

Cyclopiazonic acid type indole alkaloids from Nicotiana tabacum-derived fungus Aspergillus versicolor and their anti-tobacco mosaic virus activities.

Indole alkaloids have attracted widespread attention of chemists and biologists. Therefore, the aim of this study is to screen more bioactivities indole alkaloids from the microorganisms. In this study, five undescribed CPA-type indole alkaloids, aspergillines F-J, and three known CPA-type indole alkaloids, aspergilline A, aspergilline C, and cyclopiamide E, were obtained from the Nicotiana tabacum-derived fungus Aspergillus versicolor.

ATF2 accelerates the invasion and metastasis of hepatocellular carcinoma through targeting the miR-548p/TUFT1 axis.

Aim: Due to high invasion and metastasis, hepatocellular carcinoma (HCC) is known as one of the most fatal carcinomas. We aim to further investigate regulatory mechanisms of invasion and metastasis to elucidate HCC pathogenesis and develop novel medications.

Methods: Patient specimens were collected for assessing gene expression and correlation between gene expressions.

Pyrrolizidine alkaloids from the seeds of .

Two new pyrrolizidine alkaloids, sclerwalins A and B ( and ), and one known 9-O-E-hydroxysenecioylretronecine () were first isolated from the seeds of . Their chemical structures were elucidated by extensive 1 D NMR and 2 D NMR (HSQC, HMBC, COSY, and ROESY), MS and IR spectra. Cytotoxicities of all isolates were evaluated against five human tumor cell lines (HL-60, A-549, SMMC-7721, MCF-7 and SW480).

[Spatial and temporal variability of climatic potential productivity in Yunnan Province, China.].

We used the mean annual temperature and mean annual precipitation data during 1961 and 2017 of 101 national meteorological stations in Yunnan Province to calculate three climate-induced potential productivity in Yunnan Province by Miami model and the Thornthwaite Memorial model. The abrupt test was carried out by Mann-Kendell method. The spatial and temporal distribution characteristics and future trends of the three climate-induced potential productivities were analyzed.

[Effect of Bushen Yanggu Decoction on Multidrug Resistance of Multiple Myeloma Cell Line KM3/BTZ].

Objective: To explore the effect of Bushen Yanggu Decoction (BYD) on drug resistance and proliferation of human multiple myeloma-resistant KM3/BTZ cells.

Methods: Human multidrug-resistant KM3/BTZ cells were established by Bortezomib (BTZ) gradient induction. The effects of commonly used chemotherapeutic drugs and serum containing Bushen Yanggu Decoction (BYD) on the proliferation of KM3 cells and KM3/BTZ cells were detected by MTT assay.

Simultaneous determination of alkaloids dicentrine and sinomenine in Stephania epigeae by H NMR spectroscopy.

Stephania epigaea Lo is an important herbal medicine used as antiphlogistic and analgesic drugs. Its major components are dicentrine (1) and sinomenine (2). In the present study, a rapid, accurate, and precise method for simultaneous quantitation of dicentrine (1) and sinomenine (2) in S.

Continuously adjustable period optical grating based on flexoelectric effect of a bent-core nematic liquid crystal in planar cells.

The structures of flexodomains, which are similar to optical gratings and can be controlled by the amplitude of applied voltage and temperature, were verified through polarizing microscopy and light diffraction techniques. The properties of the optical grating induced by a bent-core nematic liquid crystal in planar cells with varied cell gaps and pretilt angles were studied. The period of optical grating decreases with the increase in the amplitude of the applied voltage and pretilt angle.

Isopentylated diphenyl ether derivatives from the fermentation products of an endophytic fungus Phomopsis fukushii.

Three new isopentylated diphenyl ethers, (1-3), together with two known isopentylated diphenyl ethers derivatives (4 and 5) were isolated from the fermentation products of an endophytic fungus Phomopsis fukushii. Their structures were elucidated by spectroscopic methods, including extensive 1D- and 2D NMR techniques. Compounds 1-3 were evaluated for their anti-methicillin-resistant Staphylococcus aureus (anti-MRSA) activity.

[Icaritin Reverses Multidrug Resistance of Multiple Myeloma Cell Line KM3/BTZ].

Objective: To investigate the reversing effect of icaritin on multidrug resistance of multiple myeloma cell lines KM3/BTZ and its underlying mechanism.

Methods: KM3/BTZ cells were established by a gradually ascending gradient induction of bortezomib (BTZ). The sensitivities of KM3 and KM3/BTZ cells to 7 chemotherapeutic drugs, the inhibition and reversal effects of icaritin on proliferation and drug-resistance of KM3/BTZ cells were analyzed by MTT.

Diet-induced obesity accelerates blood lactate accumulation of rats in response to incremental exercise to maximum.

Blood lactate increases during incremental exercise at high-intensity workloads, and limited exercise capacity is a characteristic of obese animals. This study examined whether blood lactate changes in response to incremental exercise is disrupted in obese animals. Muscular and hepatic proteins that are critical in lactate metabolism were also investigated.

Implementation of ultrafast X-ray diffraction at the 1W2B wiggler beamline of Beijing Synchrotron Radiation Facility.

The implementation of a laser pump/X-ray probe scheme for performing picosecond-resolution X-ray diffraction at the 1W2B wiggler beamline at Beijing Synchrotron Radiation Facility is reported. With the hybrid fill pattern in top-up mode, a pixel array X-ray detector was optimized to gate out the signal from the singlet bunch with interval 85 ns from the bunch train. The singlet pulse intensity is ∼2.

A new phenolic compound with antioxidant activity from the branches and leaves of Pyrus pashia.

The branches and leaves of Pyrus pashia are used to cure abdominal pain and diarrhoea in Chinese folk medicine. A new phenilic compound, 4-O-β-d-glucopyranosylbenzyl-benzoate ester (1), along with 21 known ones (2-22) were isolated from the branches and leaves of this plant. Compounds 2 and 3 displayed remarkable antioxidant activities against 1,1-diphenyl-2-picrylhydrazyl radical (IC50 = 13.

Late-onset caloric restriction alters skeletal muscle metabolism by modulating pyruvate metabolism.

Caloric restriction (CR) attenuates age-related muscle loss. However, the underlying mechanism responsible for this attenuation is not fully understood. This study evaluated the role of energy metabolism in the CR-induced attenuation of muscle loss.

Proaporphine and aporphine alkaloids with acetylcholinesterase inhibitory activity from Stephania epigaea.

An unusual proaporphine alkaloid bearing an isopropanenitrile group at isoquinoline nitrogen, named epiganine A (1) and a new aporphine alkaloid, epiganine B (2), together with eight known alkaloids, pronuciferine (3), dehydrodicentrine (4), romerine (5), romeline (6), N-methylcalycinine (7), phanostenine (8), dicentrine (9), and N-methyllaurotetanine (10), were isolated from the roots of Stephania epigaea. The absolute configuration of 1 was determined by calculating electronic circular dichroism (ECD) and comparing with experimental data. Compounds 2 and 4 showed strong acetylcholinesterase (AChE) inhibitory effects with the IC50 values of 4.

Diterpenoid alkaloids from Aconitum vilmorinianum.

Diterpenoid alkaloids, named vilmorines A-D, in addition to fifteen known alkaloids, were isolated from roots of Aconitum vilmorinianum. Their structures were established on the basis of extensive spectroscopic analyses. Antibacterial and antioxidant studies on isolated compounds were also carried out.

[Treatment of hypertension by acupuncture method of "activating blood and dispersing wind, harmonizing Gan-Pi": an analysis of its principle of the circular motion of ancient Chinese medicine].

Hypertension is one of main risk factors for the occurrence and death of stroke and coronary heart disease. Its prevalence rate is rising year by year. It severely threatens the health of the human beings.

[Clinical observation of Alzheimer's disease treated with acupuncture].

Objective: To compare the differences in the clinical efficacy on Alzheimer's disease between acupuncture and medicine.

Methods: One hundred and forty-one patients were randomized into an acupuncture group (72 cases) and a medicine group (69 cases). In the acupuncture group, the needling technique for benefiting qi, promoting blood circulation, regulating mind and improving intelligence was used at Shenting (GV 24), Baihui (GV 20), Fengchi (GB 20), Wangu (GB 12), Danzhong (CV 17), Zhangwan (CV 12), Qihai (CV 6), Xuehai (SP 10) and Zusanli (ST 36).

Cascade N-Alkylation/Hemiacetalization for Facile Construction of the Spiroketal Skeleton of Acortatarin Alkaloids with Therapeutic Potentiality in Diabetic Nephropathy.

The concise building of the spiroketal core of acortatarin-type alkaloids as potential therapeutic agents in diabetic nephropathy was established in four steps, through a tandem N-alkylation/hemiacetalization between pyrrole units and the corresponding halo alcohols generated by convenient halomethylation of chiral lactones from natural aldoses.