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101.
Nguyen Thi Quynh Mai Nguyen Thi Kim Thu Le Dac Tuyen Truong Chi Lam Vu Dinh Lam Nguyen Thi Quynh Hoa 《Plasmonics (Norwell, Mass.)》2021,16(5):1583-1592
Plasmonics - Developing a simple structure using low-cost material that enables both large-scale fabrication and broadband absorption response is highly desirable but very challenging for achieving... 相似文献
102.
John N. Freskos Bethel Asmelash Kimberly R. Gaston Amol Karwa Tim A. Marzan Maureen A. Nickols Thomas E. Rogers Tasha Schoenstein Carolyn J. Sympson Bich Vu 《Bioorganic & medicinal chemistry letters》2013,23(20):5566-5570
We describe the synthesis, MMP-2 and 9 potency, and in vitro evaluation of a series of α-sulfone hydroxmate MMP inhibitors conjugated to a series of dyes with different absorption/emission lamina maxima’s that can be used to visualize tumors. 相似文献
103.
Hui Wu Charles J. Kelley Alejandro Pino-Figueroa Huyen D. Vu Timothy J. Maher 《Bioorganic & medicinal chemistry》2013,21(17):5188-5197
Maca (Lepidium meyenii), a traditional food crop of the Peruvian Andes is now widely touted as a dietary supplement. Among the various chemical constituents isolated from the plant are a unique series of non-polar, long-chain fatty acid N-benzylamides known as macamides. We have synthesized 11 of the 19 reported macamides and have tested each as potential inhibitors of the human enzyme, fatty acid amide hydrolase (FAAH). The five most potent macamides were FAAH inhibitors (IC50 = 10–17 μM). These amides were derivatives of oleic, linoleic and linolenic acids and benzylamine or 3-methoxybenzylamine. Of the three compounds evaluated in a pre-incubation time study, two macamides were not irreversible inhibitors of FAAH. The third, a carbamate structurally related to macamides, was shown to be an irreversible inhibitor of FAAH (IC50 = 0.153 μM). 相似文献
104.
In conifers, the cytochrome P450 monooxygenase of the CYP720B family plays an important role in the synthesis of diterpene resin acids, which are specialised metabolites of the oleoresin defence. We isolated CYP720B19 from Pinus armandi and found that it belongs to the CYP720B family. The CYP720B19 open reading frame of 1467 bp encodes a protein of 488 amino acid residues with high similarity to abietadienol/abietadienal oxidase. Differential expression of the CYP720B19 gene significantly changed when plants were inoculated with the fungus Leptographium qinlingensis, mechanically wounded, or treated with methyl jasmonate (MeJa) and Tween at 4 days and 8 days. Increased expression of the CYP720B19 gene after these treatments suggested that the gene was involved in pine defence against inoculation by L. qinlingensis, MeJa treatment and mechanical injury. 相似文献
105.
Thanh Pham Nu Ngoc Doan Huyen Phan Van Giang Tran Thi Quynh Nguyen Minh Duc Tran Thanh Hung Nguyen 《Reports of Biochemistry & Molecular Biology》2022,10(4):565
Background:Orcinol-β-D-glucoside, which is also known as orcinol glucoside, is a major phenolic glucoside compound in the rhizome of the Curculigo orchioides Gaertn. This compound has many medicinal properties such as being antioxidant, immunomodulatory, antiosteoporosis, stress relief, antidepressant, etc.Methods:Determination of reducing sugar content by Bertrand’s method, determination of lipid content by Soxhlet method, determination of vitamin C content by iodine titration, determination of enzyme activity catalase by titration with KMnO4. Quantification of Orcinol-β-D-glucoside was conducted by HPLC analysis.Results:The Orcinol-β-D-glucoside of C. orchioides in Thuy Bang mountain was highest. Besides, the content of reducing sugars, vitamin C, enzyme catalase, and lipids of C. orchioides differed significantly among sites. In which, the reducing sugar and vitamin C of C. orchioides in Ngu Binh mountain was highest. Whereas, enzyme catalase was also highest in Thuy Bang mountain. However, the lipid content of C. orchioides was also highest in Huong Tho mountain.Conclusion:The result will contribute to providing the scientific basis for the selection of breeding, planting, development of C. orchioides in Thua Thien Hue province, as well as other provinces in Vietnam and opening new research directions for applications in the future.Key Words: Antioxidants, Hypoxidaceae, Medicinal Plants, Vietnam 相似文献
106.
Antroduodenal motility in chronic pancreatitis: are abnormalities related to exocrine insufficiency?
Vu MK Vecht J Eddes EH Biemond I Lamers CB Masclee AA 《American journal of physiology. Gastrointestinal and liver physiology》2000,278(3):G458-G466
In patients with chronic pancreatitis (CP) the relation among exocrine pancreatic secretion, gastrointestinal hormone release, and motility is disturbed. We studied digestive and interdigestive antroduodenal motility and postprandial gut hormone release in 26 patients with CP. Fifteen of these patients had pancreatic insufficiency (PI) established by urinary para-aminobenzoic acid test and fecal fat excretion. Antroduodenal motility was recorded after ingestion of a mixed liquid meal. The effect of pancreatic enzyme supplementation was studied in 8 of the 15 CP patients with PI. The duration of the postprandial antroduodenal motor pattern was significantly (P < 0.01) prolonged in CP patients (324 +/- 20 min) compared with controls (215 +/- 19 min). Antral motility indexes in the first hour after meal ingestion were significantly reduced in CP patients. The interdigestive migrating motor complex cycle length was significantly (P < 0.01) shorter in CP patients (90 +/- 8 min) compared with controls (129 +/- 8 min). These abnormalities were more pronounced in CP patients with exocrine PI. After supplementation of pancreatic enzymes, these alterations in motility reverted toward normal. Digestive and interdigestive antroduodenal motility are abnormal in patients with CP but significantly different from controls only in those with exocrine PI. These abnormalities in antroduodenal motility in CP are related to maldigestion. 相似文献
107.
108.
Xiaodong Xiao Bang K. Vu Dimiter S. Dimitrov 《Biochemical and biophysical research communications》2009,387(2):387-202
Isolated immunoglobulin CH2 domains were proposed as scaffolds for selection of binders with potential effector functions. We tested the feasibility of this approach by constructing a large (size 5 × 1010) library where all amino acids in two loops (BC and FG) were mutated to four residues (Y, A, D, or S). Three binders were selected from this library by panning against a gp120-CD4 complex. The strongest binder, m1a1, recognized specifically a highly conserved CD4i epitope and inhibited to various extents seven out of nine HIV-1 isolates from different clades. The loop BC and the conformational state of the scaffold are critical for its binding. These results provide a proof of concept for the potential of CH2 as a scaffold for construction of libraries containing potentially useful binders. The newly identified HIV-1 inhibitors could be further improved to candidate therapeutics and/or used as research reagents for exploration of conserved gp120 structures. 相似文献
109.
The NF-kappaB p50 is the N-terminal processed product of the precursor, p105. It has been suggested that p50 is generated not from full-length p105 but cotranslationally from incompletely synthesized molecules by the proteasome. We show that the 20S proteasome endoproteolytically cleaves the fully synthesized p105 and selectively degrades the C-terminus of p105, leading to p50 generation in a ubiquitin-independent manner. As small as 25 residues C-terminus to the site of processing are sufficient to promote processing in vivo. However, any p105 mutant that lacks complete ankyrin repeat domain (ARD) is processed aberrantly, suggesting that native processing must occur from a precursor, which extends beyond the ARD. Remarkably, the mutant p105 that lacks the internal region including the glycine-rich region (GRR) is completely degraded by 20S proteasome in vitro. This suggests that the GRR impedes the complete degradation of the p105 precursor, thus contributing to p50 generation. 相似文献
110.
NF-kappaB RelB forms an intertwined homodimer 总被引:1,自引:0,他引:1
The X-ray structure of the RelB dimerization domain (DD) reveals that the RelBDD assumes an unexpected intertwined fold topology atypical of other NF-kappaB dimers. All typical NF-kappaB dimers are formed by the association of two independently folded immunoglobulin (Ig) domains. In RelBDD, two polypeptides reconstruct both Ig domains in the dimer with an extra beta sheet connecting the two domains. Residues most critical to NF-kappaB dimer formation are invariant in RelB, and Y300 plays a positive role in RelBDD dimer formation. The presence of RelB-specific nonpolar residues at the surface removes several intradomain surface hydrogen bonds that may render the domain fold unstable. Intertwining may stabilize the RelBDD homodimer by forming the extra beta sheet. We show that, as in the crystal, RelB forms an intertwined homodimer in solution. We suggest that the transiently stable RelB homodimer might prevent its rapid degradation, allowing for heterodimer formation with p50 and p52. 相似文献