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1.
Bioorg Chem ; 139: 106710, 2023 10.
Article in English | MEDLINE | ID: mdl-37418785

ABSTRACT

The pericarps of Trichosanthes kirilowii are often used to treat cough in traditional Chinese medicine, and its ethanol extract exhibited effective therapeutic effects on acute lung injury (ALI) in vivo caused by H1N1. An anticomplement activity-guided fractionation on the extract resulted in the isolation of ten new terpenoids, including seven monoterpenoids, trichosanates A-G (1-7), and three cucurbitane-type triterpenoids, cucurbitacins W-Y (8-10), as well as eleven known terpenoids (11-21). The new terpenoids' structures were determined by spectroscopic analysis, X-ray crystallographic analysis (1), electronic circular dichroism (ECD) analysis and calculations (2-10). Twelve monoterpenoids (1-7 and 11-15) and five cucurbitane-type triterpenoids (8-10, 18, and 20) exhibited anticomplement activity in vitro. For the monoterpenoids, the long aliphatic chain substituents might enhance their anticomplement activity. Additionally, two representative anticomplement terpenoids, 8 and 11, obviously attenuated H1N1-induced ALI in vivo by inhibiting complement overactivation and reducing inflammatory responses.


Subject(s)
Influenza A Virus, H1N1 Subtype , Trichosanthes , Triterpenes , Cucurbitacins , Trichosanthes/chemistry , Monoterpenes/pharmacology , Triterpenes/pharmacology , Triterpenes/chemistry , Plant Extracts/pharmacology
2.
J Asian Nat Prod Res ; 25(2): 163-170, 2023 Feb.
Article in English | MEDLINE | ID: mdl-35675145

ABSTRACT

Two new isoflavones (1 and 2), as well as eight known ones were isolated from the roots of Sophora tonkinensis Gagnep. Compound 1 represents an unprecedented polymerization pattern constructed by isoflavone and cytisine. Their structures were elucidated by comprehensive spectroscopic data analysis, combined with ECD calculations. Compound 1 displayed significant anti-tobacco mosaic virus (TMV) activity compared with the positive control ningnanmycin. Moreover, compound 6 exhibited potent α-glucosidase inhibitory activity with IC50 value of 47.4 mg/L.


Subject(s)
Alkaloids , Isoflavones , Sophora , Isoflavones/pharmacology , Sophora/chemistry , Plant Roots/chemistry , Alkaloids/chemistry , Quinolizines/analysis
3.
J Org Chem ; 87(17): 11309-11318, 2022 09 02.
Article in English | MEDLINE | ID: mdl-35981284

ABSTRACT

Six novel Maillard reaction products (MRPs) (1-6) were isolated from the processed Thermopsis lanceolata R. Br. seed extract, along with one biogenetically related intermediate (7). Compounds 1-4 possessed three rare dimerization patterns constructed by cytisine, whereas compounds 5 and 6 represented the first example of the addition products of cytisine and 5,6-dihydroxy-4-hexanolide. Their structures were elucidated by comprehensive spectroscopic data analysis and quantum chemistry calculations including GIAO 13C{1H} NMR and ECD calculation, combined with single-crystal X-ray diffraction analysis. Biologically, compound 3 displayed significant anti-tobacco mosaic virus activity compared with the positive control ningnanmycin.


Subject(s)
Tobacco Mosaic Virus , Antiviral Agents/chemistry , Glycation End Products, Advanced , Plant Extracts/chemistry
4.
J Agric Food Chem ; 70(29): 9214-9226, 2022 Jul 27.
Article in English | MEDLINE | ID: mdl-35849433

ABSTRACT

As part of our ongoing investigation of pesticide active quinolizidine alkaloids (QAs) from the family Fabaceae, the chemical constituents of the seeds of Thermopsis lanceolata R. Br. were systematically investigated. Bioassay-guided fractionation and purification of the crude extract led to the isolation of seventeen new QAs (1-17), including three new naturally occurring compounds (15-17), along with 15 known compounds (18-32). Their structures were elucidated by comprehensive spectroscopic data analysis (IR, UV, NMR, and HRESIMS) and quantum chemistry calculations (13C NMR and ECD). The antitomato spotted wilt virus activities and insecticidal activities against Aphis fabae, Nilaparvata lugens (Stal), and Tetranychus urticae of compounds 1-32 were screened using the lesion counting method, spray method, and rice-stem dipping method, respectively. Biological tests indicated that compounds 6, 9, 10, and 18 displayed significant anti-TSWV activities compared with the positive control ningnanmycin. Compounds 3, 4, and 5 showed better insecticidal activities against A. fabae with LC50 values of 10.07, 12.07, and 6.56 mg/L, respectively. Moreover, compounds 5, 18, and 24 exhibited moderate insecticidal activities against N. lugens (Stal) with LC50 values of 37.91, 53.44, and 31.21 mg/L, respectively. Furthermore, compounds 9 and 10 exhibited moderate insecticidal activities against T. urticae.


Subject(s)
Alkaloids , Aphids , Fabaceae , Insecticides , Quinolizidines , Alkaloids/analysis , Alkaloids/pharmacology , Animals , Insecticides/chemistry , Quinolizidines/pharmacology , Seeds/chemistry
5.
Fitoterapia ; 158: 105140, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35122885

ABSTRACT

Seven undescribed thermopsine-based alkaloids (1-7), including one undescribed biogenetically related intermediate (7), were isolated from the seeds of Thermopsis lanceolata R. Br. Compound 1 possessed a 6/6-6 tricyclic skeleton, while compounds 2-6 represented three rare dimerization patterns constructed by quinolizidine alkaloids. Their structures were elucidated by comprehensive spectroscopic data analysis as well as ECD calculations. Biologically, compound 6 displayed significant anti-Tomato spotted wilt virus (TSWV) activity compared with the positive control ningnanmycin. Moreover, compound 1 exhibited good insecticidal activity against Aphis fabae with LC50 value of 25.2 mg/L.


Subject(s)
Alkaloids , Insecticides , Alkaloids/chemistry , Antiviral Agents/chemistry , Antiviral Agents/pharmacology , Insecticides/chemistry , Insecticides/pharmacology , Molecular Structure , Seeds/chemistry
6.
J Asian Nat Prod Res ; 24(12): 1141-1149, 2022 Dec.
Article in English | MEDLINE | ID: mdl-34984943

ABSTRACT

Two new (1 and 2) cytisine-type alkaloids that were chemically inseparable isomers (present in a 1:1 ratio) were identified from the seeds of Thermopsis lanceolata R. Br. Their structures were elucidated by comprehensive spectroscopic data analysis (IR, UV, NMR, HRESIMS) and ECD calculation. Compound 1 displayed significant anti-tobacco mosaic virus (TMV) activity, while compounds 1 and 2 displayed moderate insecticidal activities against Aphis fabae with LC50 value of 43.15 and 46.47 mg/L, respectively.


Subject(s)
Alkaloids , Fabaceae , Molecular Structure , Quinolizines/pharmacology , Alkaloids/pharmacology , Alkaloids/chemistry , Azocines , Seeds , Antiviral Agents/chemistry
7.
IEEE Trans Med Imaging ; 40(12): 3728-3738, 2021 12.
Article in English | MEDLINE | ID: mdl-34260351

ABSTRACT

Polarization images encode high resolution microstructural information even at low resolution. We propose a framework combining polarization imaging and traditional microscopy imaging, constructing a dual-modality machine learning framework that is not only accurate but also generalizable and interpretable. We demonstrate the viability of our proposed framework using the cervical intraepithelial neoplasia grading task, providing a polarimetry feature parameter to quantitatively characterize microstructural variations with lesion progression in hematoxylin-eosin-stained pathological sections of cervical precancerous tissues. By taking advantages of polarization imaging techniques and machine learning methods, the model enables interpretable and quantitative diagnosis of cervical precancerous lesion cases with improved sensitivity and accuracy in a low-resolution and wide-field system. The proposed framework applies routine image-analysis technology to identify the macro-structure and segment the target region in H&E-stained pathological images, and then employs emerging polarization method to extract the micro-structure information of the target region, which intends to expand the boundary of the current image-heavy digital pathology, bringing new possibilities for quantitative medical diagnosis.


Subject(s)
Precancerous Conditions , Uterine Cervical Dysplasia , Uterine Cervical Neoplasms , Female , Humans , Machine Learning , Microscopy , Precancerous Conditions/diagnostic imaging , Uterine Cervical Neoplasms/diagnostic imaging
8.
J Asian Nat Prod Res ; 23(7): 644-651, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33583289

ABSTRACT

Two new compounds, including one new arylbenzofuran (1) and one new pterocarpanoid (2), along with nine known ones, were isolated from the seeds of Sophora tonkinensis. The structures of the new compounds were elucidated based on a comprehensive spectroscopic data analysis. Compounds 2 and 3 exhibited good anti-tobacco mosaic virus (TMV) activities with the protective inhibition rate of 69.62% and 68.72% respectively, at concentration of 100 µg/ml.


Subject(s)
Sophora , Tobacco Mosaic Virus , Antiviral Agents/pharmacology , Molecular Structure , Seeds
9.
J Agric Food Chem ; 68(50): 15015-15026, 2020 Dec 16.
Article in English | MEDLINE | ID: mdl-33285067

ABSTRACT

The discovery of novel, effective, and botanical pesticides is one of the main strategies for modern plant protection and insect pest control. During the search for novel botanical pesticides from natural sources, the seeds of Sophora tonkinensis were systematically investigated to obtain 11 new matrine-type alkaloids (1-11), including one novel matrine-type alkaloid featuring an unprecedented 5/6/6/6 tetracyclic skeleton (1), along with 16 known compounds (12-27). Their structures were elucidated by comprehensive spectroscopic data analysis (IR, UV, NMR, and HRESIMS), ECD calculations, and single-crystal X-ray diffraction. The anti-tobacco mosaic virus (TMV) activity and insecticidal activities against Aphis fabae and Tetranychus urticae of the compounds were also respectively screened using the half-leaf method and spray method. Biological tests indicated that compounds 2, 4, 6, and 26 displayed significant anti-TMV biological activities compared with the positive control ningnanmycin. Compounds 7, 17, and 26 presented moderate activities against A. fabae with LC50 values of 38.29, 18.63, and 23.74 mg/L, respectively. Moreover, compounds 13 and 26 exhibited weak activities against T. urticae.


Subject(s)
Alkaloids/pharmacology , Antiviral Agents/pharmacology , Insecticides/pharmacology , Plant Extracts/pharmacology , Quinolizidines/pharmacology , Sophora/chemistry , Alkaloids/chemistry , Animals , Antiviral Agents/chemistry , Insecta/drug effects , Insecta/growth & development , Insecticides/chemistry , Plant Extracts/chemistry , Quinolizidines/chemistry , Seeds/chemistry , Tobacco Mosaic Virus/drug effects , Tobacco Mosaic Virus/growth & development
10.
ScientificWorldJournal ; 2014: 265816, 2014.
Article in English | MEDLINE | ID: mdl-25177717

ABSTRACT

Deep-sea permanent magnet motor equipped with fluid compensated pressure-tolerant system is compressed by the high pressure fluid both outside and inside. The induced stress distribution in stator core is significantly different from that in land type motor. Its effect on the magnetic properties of stator core is important for deep-sea motor designers but seldom reported. In this paper, the stress distribution in stator core, regarding the seawater compressive stress, is calculated by 2D finite element method (FEM). The effect of compressive stress on magnetic properties of electrical steel sheet, that is, permeability, BH curves, and BW curves, is also measured. Then, based on the measured magnetic properties and calculated stress distribution, the stator iron loss is estimated by stress-electromagnetics-coupling FEM. At last the estimation is verified by experiment. Both the calculated and measured results show that stator iron loss increases obviously with the seawater compressive stress.


Subject(s)
Compressive Strength , Electrical Equipment and Supplies , Iron/chemistry , Magnetic Fields , Seawater/adverse effects , Steel/chemistry
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