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1.
From the roots of Ferula loscosii the coumarins umbelliprenin, coladin and coladonin and the new natural isovaleryl derivative of the latter have been isolated. A study which confirms the structure of coladonin and its difference from farnesiferol A is also given.  相似文献   
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The structure and absolute configuration of desangeloylshairidin, a guaianolide isolated from Guillonea scabra, have been established by X-ray diffraction analysis. No conformational change was observed in its seven-membered ring between the crystal and deuterochloroform solution states.  相似文献   
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Microfluidic technologies are highly adept at generating controllable compositional gradients in fluids, a feature that has accelerated the understanding of the importance of chemical gradients in biological processes. That said, the development of versatile methods to generate controllable compositional gradients in the solid‐state has been far more elusive. The ability to produce such gradients would provide access to extensive compositional libraries, thus enabling the high‐throughput exploration of the parametric landscape of functional solids and devices in a resource‐, time‐, and cost‐efficient manner. Herein, the synergic integration of microfluidic technologies is reported with blade coating to enable the controlled formation of compositional lateral gradients in solution. Subsequently, the transformation of liquid‐based compositional gradients into solid‐state thin films using this method is demonstrated. To demonstrate efficacy of the approach, microfluidic‐assisted blade coating is used to optimize blending ratios in organic solar cells. Importantly, this novel technology can be easily extended to other solution processable systems that require the formation of solid‐state compositional lateral gradients.  相似文献   
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Neurochemical Research - A selective RXR agonist, bexarotene, has been shown to have anti-inflammatory, anti-nociceptive, and neuroprotective effects in several models of numerous neurological...  相似文献   
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The antioxidant role of novel N-substituted indole-2-carboxamides (I2CDs) was investigated for their inhibitory effects on superoxide anion (O2? ) and lipid peroxidation (LP). Among the synthesized I2CDs, 3, 4, 6, 8 and 9 significantly inhibited O2· ? with an inhibition range at 70–98%. Examination of substituent effects on activity showed that both the ortho- and para-positions of the benzamide residue needs to be dichlorinated in order to get a maximum inhibitory effect on superoxide anion. In general, halogenated derivatives were found more active then the non-halogenated ones. However, none of the I2CDs had a significant inhibitory effects on the level of lipid peroxidation; only compounds 7 and 10 moderately decreased LP levels by over 50% at 10? 3 M concentrations.  相似文献   
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Oxidative stress has been implicated in the development of many neurodegenerative diseases and also responsible from aging and some cancer types. Indolic compounds are a broad family of substances present in microorganisms, plants and animals. They are mainly related to tryptophan metabolism, and present particular properties that depend on their respective chemical structures. Due to free radical scavenger and antioxidant properties of indolic derivatives such as indolinic nitroxides and melatonin, a series of 2-phenyl indole derivatives were prepared and their in vitro effects on rat liver lipid peroxidation levels, superoxide formation and DPPH stable radical scavenging activities were determined against melatonin, BHT and α-tocopherol. The compounds significantly inhibited (72–98%) lipid peroxidation at 10? 3 M. These values were similar to that observed with BHT (88%). Possible structure–activity relationships of the compounds were discussed.  相似文献   
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Turnip oil (TO; Raphanus sativus L.) produces seeds that contain around 26 wt% of inedible base stock that are suitable as a potential feedstock for biodiesel production. A turnip oil methyl ester (TME) was prepared from acid-catalyzed pretreated TO in an effort to evaluate important fuel properties of turnip oil-based biodiesel, such as kinematic viscosity, cloud point, pour point (PP), cold filter plugging point, acid value, oxidative stability and lubricity. A comparison was made with soybean oil methyl esters (SME) as per biodiesel fuel standards such as ASTM D6751 and EN 14214. TME was characterized using FTIR, HPLC and 1H NMR. Except PP property, SME displays superior fuel properties compared to TME. Blends (B5 and B20) of TME in ultra-low sulphur diesel fuel (ULSD) were also assessed for the aforesaid fuel properties and compared to an analogous set of blends of soybean oil methyl ester in ULSD as per petro diesel fuel standards such as ASTM D975 and D7467. TME B5 blends in ULSD displayed improved PP property in comparison to neat ULSD and blends of SME in ULSD. It was demonstrated that the B5 and B20 blends of TME in ULSD had acceptable fuel properties as per ASTM D975 (for B5 blend) and ASTM D7467 (for B20 blend). In summary, turnip oil has potential as an alternative, non-food feedstock for biodiesel production.  相似文献   
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We exploited the amenability of the fungus Aspergillus nidulans to genetics and live-cell microscopy to investigate autophagy. Upon nitrogen starvation, GFP-Atg8-containing pre-autophagosomal puncta give rise to cup-shaped phagophores and circular (0.9-μm diameter) autophagosomes that disappear in the vicinity of the vacuoles after their shape becomes irregular and their GFP-Atg8 fluorescence decays. This ‘autophagosome cycle’ gives rise to characteristic cone-shaped traces in kymographs. Autophagy does not require endosome maturation or ESCRTs, as autophagosomes fuse with vacuoles directly in a RabS (homolog of Saccharomyces cerevisiae Ypt7 and mammalian RAB7; written hereafter as RabSRAB7)-HOPS-(homotypic fusion and vacuole protein sorting complex)-dependent manner. However, by removing RabSRAB7 or Vps41 (a component of the HOPS complex), we show that autophagosomes may still fuse, albeit inefficiently, with the endovacuolar system in a process almost certainly mediated by RabARAB5/RabBRAB5 (yeast Vps21 homologs)-CORVET (class C core vacuole/endosome tethering complex), because acute inactivation of HbrA/Vps33, a key component of HOPS and CORVET, completely precludes access of GFP-Atg8 to vacuoles without affecting autophagosome biogenesis. Using a FYVE2-GFP probe and endosomal PtdIns3P-depleted cells, we imaged PtdIns3P on autophagic membranes. PtdIns3P present on autophagosomes decays at late stages of the cycle, preceding fusion with the vacuole. Autophagy does not require Golgi traffic, but it is crucially dependent on RabORAB1. TRAPPIII-specific factor AN7311 (yeast Trs85) localizes to the phagophore assembly site (PAS) and RabORAB1 localizes to phagophores and autophagosomes. The Golgi and autophagy roles of RabORAB1 are dissociable by mutation: rabOA136D hyphae show relatively normal secretion at 28°C but are completely blocked in autophagy. This finding and the lack of Golgi traffic involvement pointed to the ER as one potential source of membranes for autophagy. In agreement, autophagosomes form in close association with ring-shaped omegasome-like ER structures resembling those described in mammalian cells.  相似文献   
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