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871.
Trinh Thi Thuy Nguyen Thi Thu Hoa Nguyen Thi Thuy Linh Ba Thi Cham Nguyen Thi Hoang Anh Nguyen Tuan Hiep Sabrina Adorisio Domenico V Delfino Ngo Anh Bang Bui Huu Tai Phan Van Kiem 《化学与生物多样性》2023,20(10):e202301166
Gnetum latifolium var. funiculare Markgr. is a medicinal plant and widely distributed in mountainous areas of Vietnam. Phytochemical investigation on the trunks of this plant afforded eight stilbene derivatives ( 1 – 8 ) including for new compounds ( 1 – 4 ). Their structures were determined based on extensive analyses of HR-ESI-MS, 1D and 2D NMR spectra. Among the isolates, compounds 1 – 3 showed moderate NO production inhibition in LPS-activated RAW264.7 cells with the IC50 values ranging from 46.81 to 68.10 μM, compounds 4 and 6 showed weak effects with the IC50 values of 96.57 and 79.46 μM, respectively, compared to that of the positive control compound, dexamethasone (IC50 14.20 μM). 相似文献
872.
Aline-Marie Wauters Marie-Annick Richard-Yris & Nolwenn Talec 《Ethology : formerly Zeitschrift fur Tierpsychologie》2002,108(6):529-540
The aim of this study was to determine if and how the presence of a hen influences the behaviour of chicks and, more precisely, their food preferences. We observed two types of young, brooded and non‐brooded chicks in the presence of three different food types. Results revealed that brooded chicks performed more locomotion and more sustained feeding activities than non‐brooded chicks. Moreover, brooded chicks had different preferences from non‐brooded chicks and very clearly followed their mother's preferences. We concluded that social facilitation and local enhancement could play a significant role in determining the importance of feeding activities and preferences of brooded chicks. 相似文献
873.
Poulomi Das Khac Huy Ngo Fernaldo
Richtia Winnerdy Arijit Maity Bla Bakalar Yves Mechulam Emmanuelle Schmitt Anh Tun Phan 《Nucleic acids research》2021,49(3):1724
G-quadruplex (G4) DNA structures with a left-handed backbone progression have unique and conserved structural features. Studies on sequence dependency of the structures revealed the prerequisites and some minimal motifs required for left-handed G4 formation. To extend the boundaries, we explore the adaptability of left-handed G4s towards the existence of bulges. Here we present two X-ray crystal structures and an NMR solution structure of left-handed G4s accommodating one, two and three bulges. Bulges in left-handed G4s show distinct characteristics as compared to those in right-handed G4s. The elucidation of intricate structural details will help in understanding the possible roles and limitations of these unique structures. 相似文献
874.
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876.
Tran Cuong Duy Chu Ha Duc Nguyen Kien Huu Watanabe Yasuko La Hong Viet Tran Khanh Dang Tran Lam-Son Phan 《Journal of Plant Growth Regulation》2018,37(4):1286-1299
Journal of Plant Growth Regulation - Chickpea (Cicer arietinum L.) is regarded as one of the important grain legumes of the Fabaceae family and being consumed in many... 相似文献
877.
Kathryn A. Jewett Ruth E. Thomas Chi Q. Phan Bernice Lin Gillian Milstein Selina Yu Lisa F. Bettcher Fausto Carnevale Neto Danijel Djukovic Daniel Raftery Leo J. Pallanck Marie Y. Davis 《PLoS genetics》2021,17(2)
Abnormal protein aggregation within neurons is a key pathologic feature of Parkinson’s disease (PD). The spread of brain protein aggregates is associated with clinical disease progression, but how this occurs remains unclear. Mutations in glucosidase, beta acid 1 (GBA), which encodes glucocerebrosidase (GCase), are the most penetrant common genetic risk factor for PD and dementia with Lewy bodies and associate with faster disease progression. To explore how GBA mutations influence pathogenesis, we previously created a Drosophila model of GBA deficiency (Gba1b) that manifests neurodegeneration and accelerated protein aggregation. Proteomic analysis of Gba1b mutants revealed dysregulation of proteins involved in extracellular vesicle (EV) biology, and we found altered protein composition of EVs from Gba1b mutants. Accordingly, we hypothesized that GBA may influence pathogenic protein aggregate spread via EVs. We found that accumulation of ubiquitinated proteins and Ref(2)P, Drosophila homologue of mammalian p62, were reduced in muscle and brain tissue of Gba1b flies by ectopic expression of wildtype GCase in muscle. Neuronal GCase expression also rescued protein aggregation both cell-autonomously in brain and non-cell-autonomously in muscle. Muscle-specific GBA expression reduced the elevated levels of EV-intrinsic proteins and Ref(2)P found in EVs from Gba1b flies. Perturbing EV biogenesis through neutral sphingomyelinase (nSMase), an enzyme important for EV release and ceramide metabolism, enhanced protein aggregation when knocked down in muscle, but did not modify Gba1b mutant protein aggregation when knocked down in neurons. Lipidomic analysis of nSMase knockdown on ceramide and glucosylceramide levels suggested that Gba1b mutant protein aggregation may depend on relative depletion of specific ceramide species often enriched in EVs. Finally, we identified ectopically expressed GCase within isolated EVs. Together, our findings suggest that GCase deficiency promotes accelerated protein aggregate spread between cells and tissues via dysregulated EVs, and EV-mediated trafficking of GCase may partially account for the reduction in aggregate spread. 相似文献
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879.
R T Phan The TranPhan 《Archives de l'Institut Pasteur de Tunis》1979,56(3):279-284
Preparation, standardization and use of the Limulus test, in relation to the official Rabbit test. Applications of the Limulus test to radiopharmaceuticals. 相似文献
880.
Kumari Pragati Singh Sumer Yadav Saurabh Tran Lam-Son Phan 《Journal of plant research》2021,134(5):1149-1154
Journal of Plant Research - A comparative regeneration of three types of explants prepared from axillary meristems, plumular apices and hypocotyls of chickpea (Cicer arietinum) was carried out... 相似文献