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91.
Tran Thi Thu Ha Nguyen Thi Cuc Bui Huu Tai Khuat Huu Trung Tran Dang Khanh Phan Van Kiem 《化学与生物多样性》2023,20(8):e202300731
Four undescribed compounds ( 1 – 4 ) named pelliolatifolias A−D together with seven known compounds trans-clovamide ( 5 ), N-trans-caffeoyl-4-hydroxyphenylalanine methyl ester ( 6 ), N-trans-caffeoyl-3,4-dihydroxyphenylalanine methyl ester ( 7 ), luteolin 4’-O-β-D-glucopyrannoside ( 8 ), cis-syringin ( 9 ), trans-syringin ( 10 ), and citroside A ( 11 ) have been isolated from the methanol extract of the Pellionia latifolia leaves. Their chemical structures were elucidated based on extensive analyses of HR-ESI-MS, 1D and 2D NMR, and CD spectra. Compounds 1 – 7 , 9 and 10 showed moderate inhibition of NO production in LPS-activated RAW264.7 cells with their IC50 values ranging from 39.27 to 75.42 μM, compared to that of the positive control compound, dexamethasone, IC50 value of 14.20 μM. 相似文献
92.
Nguyen Trung Thanh La Thi Thuy Do Thi Xuyen Le Quynh Mai Do Van Hai Nguyen Sinh Khang Do Thi Trang Bui Huu Tai Phan Van Kiem 《化学与生物多样性》2023,20(6):e202300604
Phytochemical study on the leaves of Amentotaxus yunnanensis led to the isolation of seventeen phenolic compounds including sixteen neolignans and lignans, and one flavone glycoside. Three among the isolates were previously unreported neolignans and named as amenyunnaosides A–C, respectively. Their structures were elucidated by extensive analyses of HR-ESI-MS, 1D and 2D NMR, and ECD spectra. The isolated neolignans potentially inhibited NO production in LPS-activated RAW264.7 cells with their IC50 values ranging from 11.05 to 44.07 μM, compared to that of the positive control compound, dexamethasone, IC50 value of 16.93 μM. Additionally, amenyunnaoside A dose-dependently reduced production of IL-6 and COX-2 but did not effect to that of TNF-α at concentrations of 0.8, 4, and 20 μM. 相似文献
93.
Pham Thi Hang Nguyen Thi Hue Nguyen Hoang Nam Nguyen Le Tuan Pham Van Cuong Nguyen Quoc Vuong Dan Thi Thuy Hang Bui Huu Tai Phan Van Kiem 《化学与生物多样性》2023,20(9):e202301090
A phytochemical investigation of the methanolic extract of the Macropanax membranifolius C.B. Shang leaves led to the isolation of three new flavans, (2R,3R)-4′-O-methylcatechin 5-O-β-D-glucopyranoside ( 1 ), (2S,3S)-4′-O-methylcatechin 5-O-β-D-glucopyranoside ( 2 ), (2S,3R)-4′-O-methylcatechin 5-O-β-D-glucopyranoside ( 3 ), one new triterpene glycoside 3-O-β-D-xylopyranosyl-(1→6)-[β-D-xylopyranosyl-(1→2)]-β-D-glucopyranosyl-oleanolic acid 28-O-β-D-glucopyranoside ( 4 ), together with nine known compounds ( 5 - 13 ). Their chemical structures were elucidated based on HR-ESI-MS, NMR spectroscopic data. The absolute configurations of compounds 1 – 3 were established by electronic circular dichroism (ECD) spectra. At concentration of 20 μM, compounds 1 – 13 showed the percentages of dead cell in the range of 2.14 % to 33.61 % against KB, HepG2, HL60, P388, HT29, and MCF7 cancerous cell lines by SRB assay. 相似文献
94.
Morphogenesis in tobacco subepidermal cells: Putrescine as marker of root differentiation 总被引:2,自引:0,他引:2
Antonio F. Tiburcio Cyrille Amin Gendy Kiem Tran Thanh Van 《Plant Cell, Tissue and Organ Culture》1989,19(1):43-54
We have used the tobacco thin cell layer in vitro system to evaluate changes in polyamine titers as correlated with root differentiation and with variations in external pH during culture. We show that root differentiation in this system depends on both a rise in putrescine titers and a drop of pH, each of these two factors acting independently. With respect to polyamine titers, the most dramatic changes occur in the levels of putrescine liberated from perchloric acid-soluble conjugates. These titers increase from day 0 to day 7 of culture, reaching almost 2000 nmol g-1 fresh weight. Inhibition of putrescine biosynthesis prevents root initiation, while exogenous putrescine supply reverses this effect. We conclude that putrescine is a good marker for root differentiation. 相似文献
95.
Thirty-three dairy farms in the Norwegian counties of ?stfold and Akershus in which cubicle sheds had been in use for at least
one year and with a herd size of less than 60 cows, were contacted and asked to participate in a study. The study focused
on heifers' use of cubicles and concentrate dispenser just after being transferred from rearing accommodation to the milking
herd. For each heifer, the farmer recorded cubicle use once nightly between 9 and 11 pm. The daily amount of concentrate released
in the dispenser and the allotted daily ration were also recorded. The recording period was 15 consecutive days for cubicle
use and 7 days for concentrate dispenser use. Cubicle refusal behaviour, i.e. lying outside the cubicles, was analysed by
logistic regression using rearing accommodation of heifers, herd size, heifer age, and housing layout as independent variables,
and herd as a clustering variable. On Day 2 after transfer, 34% of the heifers were showing cubicle refusal behaviour (N =
340). By Day 15 this percentage had dropped to 23. Cubicle refusal was lower throughout the whole period among heifers which
used the cubicles on the 3 first days after transfer compared to those which did not. This tendency could also be detected
several months later. The analysis showed cubicle refusal to be significantly associated with rearing accommodation (OR =
6.1, c.i.95%OR = 1.5–24.3, P = 0.01) and cubicle layout in the shed (OR = 0.2, c.i.95%OR = 0.0–0.7, P = 0.01). None of the tested variables were found to be significant for failure to use the concentrate dispenser,
a behaviour which was less frequent than cubicle refusal. However, 8 percent of the heifers did not visit the dispenser at
all throughout the 7 days of observation. 相似文献
96.
Nguyen Xuan Cuong Le Thi Vien Le Hoang Tran Thi Hong Hanh Do Thi Thao Nguyen Van Thanh Nguyen Hoai Nam Do Cong Thung Phan Van Kiem Chau Van Minh 《Bioorganic & medicinal chemistry letters》2017,27(13):2939-2942
Using various chromatographic separation techniques, eight triterpene diglycosides (1–8), including four new compounds namely stichorrenosides A–D (1–4), were isolated from a methanol extract of the Vietnamese sea cucumber S. horrens. Their structures were elucidated based on spectroscopic analyses, including HR ESI MS, 1D and 2D NMR. Their in vitro cytotoxic activity against five human cancer cell lines, Hep-G2 (hepatoma cancer), KB (epidermoid carcinoma), LNCaP (prostate cancer), MCF7 (breast cancer), and SK-Mel2 (melanoma), was evaluated using SRB methods. Stichorrenoside D (4), stichoposide A (5), and 3β-O-[β-d-xylopyranosyl-(1→2)-β-d-xylopyranosyl]-23S-acetoxyholost-7-ene (7) showed strong cytotoxicity on all five tested cancer cell lines, whereas significant effect was observed for stichorrenoside C (3) and stichoposide B (6). 相似文献
97.
Chemical Components from Phaeanthus vietnamensis and Their Inhibitory NO Production in BV2 Cells
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Nguyen Xuan Nhiem Nguyen Trung Tuong Pham Thanh Ky Lalita Subedi Seon Ju Park Tran Minh Ngoc Pham Hai Yen Bui Huu Tai Tran Hong Quang Phan Van Kiem Sun Yeou Kim Seung Hyun Kim 《化学与生物多样性》2017,14(8)
Phaeanthus vietnamensis Bân is a well‐known medicinal plant which has been used for the treatment of various inflammatory diseases in traditional medicine. Using various chromatographic methods, three new compounds, (7S,8R,8′R)‐9,9′‐epoxy‐3,5,3′,5′‐tetramethoxylignan‐4,4′,7‐triol ( 1 ), 8α‐hydroxyoplop‐11(12)‐en‐14‐one ( 5 ), and (1R,2S,4S)‐4‐acetyl‐2‐[(E)‐(cinnamoyloxy)]‐1‐methylcyclohexan‐1‐ol ( 12 ) along with twelve known compounds were isolated from the leaves of P. vietnamensis. Their chemical structures were elucidated by physical and chemical methods. All compounds were evaluated for the inhibitory activities of nitric oxide production in LPS‐stimulated BV2 cells. As the results, compound 6 showed the most potent inhibitory activity on LPS‐stimulated NO production in BV2 cells with the IC50 values of 15.7 ± 1.2 μm . Compounds 2 , 7 , and 8 significantly inhibited inflammatory NO production with IC50 values ranging from 22.6 to 25.3 μm . 相似文献
98.
Efficient generation of antigen-specific cytotoxic T cells using retrovirally transduced CD40-activated B cells 总被引:4,自引:0,他引:4
Kondo E Topp MS Kiem HP Obata Y Morishima Y Kuzushima K Tanimoto M Harada M Takahashi T Akatsuka Y 《Journal of immunology (Baltimore, Md. : 1950)》2002,169(4):2164-2171
The development of rapid, efficient, and safe methods for generating Ag-specific T cells is necessary for the clinical application of adoptive immunotherapy. We show that B cells stimulated with CD40 ligand and IL-4 (CD40-B cells) can be efficiently transduced with retroviral vectors encoding a model Ag, CMV tegument protein pp65 gene, and maintain high levels of costimulatory molecules after gene transfer. CTL lines specific for pp65 were readily generated in all four healthy CMV-seropositive donors by stimulating autologous CD8(+) T cells with these transduced CD40-B cells, both of which were derived from 10 ml peripheral blood. ELISPOT assays revealed that the CTL lines used multiple HLA alleles as restricting elements. Thus, CD40-B cells transduced retrovirally with Ag-encoding cDNA can be potent APC and facilitate to generate Ag-specific CTL in vitro. 相似文献
99.
A diagnosis of glioblastoma multiforme (GBM) was made for cerebral masses found at necropsy in two baboons (Papio cynocephalus anubis). Case 1 was an adult (6.18 years old) male baboon that suddenly died during a physical examination as part of a clinical evaluation for a leg lameness. Case 2 was an adult (5.95 years old) female baboon that stopped breathing during anesthesia for an magnetic resonance imaging to evaluate lethargy, weight loss, inappetence, and dilated pupils. Both animals had undergone total body irradiation with cobalt during a research protocol. The incidence of spontaneous brain tumors in nonhuman primates is low, but radiation-induced GBM lesions in rhesus macaques (Macaca mulatta) have been reported. A definitive diagnosis was made in these cases, using histopathologic criteria of cellular pleomorphism, high mitotic rate, regions of coagulation necrosis, and endothelial proliferation. 相似文献
100.