210 research outputs found
Using UWB Sensor for Delta Robot Vibration Detection
Abstract-This study proposed the ultra-wideband(UWB) sensor to detect the vibration of the delta robot and the distance between UWB sensor and robot arm. Based on the radar propagating principle and the proposed algorithm, the vibration status of robot arm can be obtained. Besides, the vibration status can be reduced by feedback the information to the controller of the robot arm. The advantage of the proposed sensor is that without contacting to the robot arm, UWB sensor is more flexible to be used and will not cause any unnecessary payload as accelerometers. With proper calibration, the simulation of vibration frequency and the real-time absolute position of the robot arm were calculated and demonstrated. The experimental results show that the correlations for measured frequency and distance approximate to 1
Discovery of New Eunicellins from an Indonesian Octocoral Cladiella sp.
Two new 11-hydroxyeunicellin diterpenoids, cladieunicellin F (1) and (–)-solenopodin C (2), were isolated from an Indonesian octocoral Cladiella sp. The structures of eunicellins 1 and 2 were established by spectroscopic methods, and eunicellin 2 was found to be an enantiomer of the known eunicellin solenopodin C (3). Eunicellin 2 displayed inhibitory effects on the generation of superoxide anion and the release of elastase by human neutrophils. The previously reported structures of two eunicellin-based compounds, cladielloides A and B, are corrected in this study
Lobocrassins A–E: New Cembrane-Type Diterpenoids from the Soft Coral Lobophytum crassum
Five new cembrane-type diterpenoids, lobocrassins A–E (1–5), were isolated from the soft coral Lobophytum crassum. The structures of cembranes 1–5 were established by spectroscopic and chemical methods and by comparison of the spectral data with those of known cembrane analogues. Lobocrassin A (1) is the first cembranoid possessing an α-chloromethyl-α-hydroxy-γ-lactone functionality and is the first chlorinated cembranoid from soft corals belonging to the genus Lobophytum. Lobocrassins B (2) and C (3) were found to be the stereoisomers of the known cembranes, 14-deoxycrassin (6) and pseudoplexaurol (7), respectively. Lobocrassin B (2) exhibited modest cytotoxicity toward K562, CCRF-CEM, Molt4, and HepG2 tumor cells and displayed significant inhibitory effects on the generation of superoxide anion and the release of elastase by human neutrophils
Cladielloides A and B: New Eunicellin-Type Diterpenoids from an Indonesian Octocoral Cladiella sp
Two new eunicellin-type diterpenoids, cladielloides A (1) and B (2), which were found to possess a 2-hydroxybutyroxy group in their structures, were isolated from an Indonesian octocoral identified as Cladiella sp. The structures of eunicellins 1 and 2 were elucidated by spectroscopic methods. Cladielloide B (2) exhibited moderate cytotoxicity toward CCRF-CEM tumor cells and this compound displayed significant inhibitory effects on superoxide anion generation and elastase release by human neutrophils
Carijoside A, a Bioactive Sterol Glycoside from an Octocoral Carijoa sp. (Clavulariidae)
A new bioactive sterol glycoside, 3β-O-(3′,4′-di-O-acetyl-β-d-arabinopyranosyl) -25ξ-cholestane-3β,5α,6β,26-tetrol-26-acetate) (carijoside A, 1), was isolated from an octocoral identified as Carijoa sp. The structure of glycoside 1 was established by spectroscopic methods and by comparison with spectral data for the other known glycosides. Carijoside A (1) displayed significant inhibitory effects on superoxide anion generation and elastase release by human neutrophils and this compound exhibited moderate cytotoxicity toward DLD-1, P388D1, HL-60, and CCRF-CEM tumor cells
AMG 837: A Novel GPR40/FFA1 Agonist that Enhances Insulin Secretion and Lowers Glucose Levels in Rodents
Agonists of GPR40 (FFA1) have been proposed as a means to treat type 2 diabetes. Through lead optimization of a high throughput screening hit, we have identified a novel GPR40 agonist called AMG 837. The objective of these studies was to understand the preclinical pharmacological properties of AMG 837. The activity of AMG 837 on GPR40 was characterized through GTPγS binding, inositol phosphate accumulation and Ca2+ flux assays. Activity of AMG 837 on insulin release was assessed on isolated primary mouse islets. To determine the anti-diabetic activity of AMG 837 in vivo, we tested AMG 837 using a glucose tolerance test in normal Sprague-Dawley rats and obese Zucker fatty rats. AMG 837 was a potent partial agonist in the calcium flux assay on the GPR40 receptor and potentiated glucose stimulated insulin secretion in vitro and in vivo. Acute administration of AMG 837 lowered glucose excursions and increased glucose stimulated insulin secretion during glucose tolerance tests in both normal and Zucker fatty rats. The improvement in glucose excursions persisted following daily dosing of AMG 837 for 21-days in Zucker fatty rats. Preclinical studies demonstrated that AMG 837 was a potent GPR40 partial agonist which lowered post-prandial glucose levels. These studies support the potential utility of AMG 837 for the treatment of type 2 diabetes
Excavatoids O and P, New 12-Hydroxybriaranes from the Octocoral Briareum excavatum
Two new 12-hydroxybriarane diterpenoids, designated as excavatoids O (1) and P (2), were isolated from the octocoral Briareum excavatum. The structures of briaranes 1 and 2 were established on the basis of extensive spectral data analysis. Excavatoid P (2) is the first metabolite which possesses a 6β -chlorine atom in briarane analogues
Terpenoids from the Octocorals Menella sp. (Plexauridae) and Lobophytum crassum (Alcyonacea)
A new germacrane-type sesquiterpenoid, menelloide E (1), and a new cembrane-type diterpenoid, lobocrassin F (2), were isolated from the octocorals Menella sp. and Lobophytum crassum, respectively. The structures of terpenoids 1 and 2 were determined by spectroscopic and chemical methods and compound 2 was found to display a significant inhibitory effect on the release of elastase by human neutrophils
Excavatoids E and F: Discovery of Two New Briaranes from the Cultured Octocoral Briareum excavatum
Two new briarane-related diterpenoids, designated as excavatoids E (1) and F (2), were isolated from the cultured octocoral Briareum excavatum. The structures of compounds 1 and 2 were established on the basis of extensive spectral data analysis. Briaranes 1 and 2 were found to exhibit moderate inhibitory effects on elastase release by human neutrophils
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