Chemical constituents of lawang root oil

Spectroscopic analysis of lawang root oil identified methyl salicylate as the major component. This result contrasts with the known composition of bark-derived lawang oil, in which eugenol is the major component. The validity of the compositional analysis was confirmed by extraction of an authentic sample of plant root tissue, and comparison with the commercially available essential oil

Identification of mammalian lipid material by high performance liquid chromatography and Fourier transform ion cyclotron resonance mass spectrometry

The analysis of the exact compositions of human lipids is of great importance and canlead to a better understanding of the role of lipids in heart diseases and diabetes.Reverse phase and normal phase high performance liquid chromatography has beenused for the analysis of lipid material and applied to beef dripping. Electrosprayionization Fourier transform ion cyclotron resonance mass spectrometry has been usedto investigate the free fatty acids, monoacylglycerides, diacylglycerides andtriacylglycerides present in lard and beef dripping with the general conclusion that thisis a semi quantitative method. Collision induced dissociation of di- and triacylglycerideswas performed using Fourier transform ion cyclotron resonance mass spectrometry withthe energy of activation for the fragmentation process investigated and compared usingdensity functional theory and Rice Ramsperger Kassel Marcus statistical theory offragmentation. The application of tandem mass spectrometry to mice and human cellcultures and plaques from the abdominal aorta of rabbits was conducted using normalphase high performance liquid chromatography with electrospray ionization Fouriertransform ion cyclotron resonance mass spectrometry and quadrupole time of flightmass spectrometry

Mass and relative elution time profiling: Two-dimensional analysis of sphingolipids in Alzheimer\u27s disease brains

Current lipidomic profiling methods rely mainly on MS to identify unknown lipids within a complex sample. We describe a new approach, involving LC×MS/MS (liquid chromatography×tandem MS) analysis of sphingolipids based on both mass and hydrophobicity, and use this method to characterize the SM (sphingomyelin), ceramide and GalCer (galactosylceramide) content of hippocampus from AD (Alzheimer\u27s disease) and control subjects. Using a mathematical relationship we exclude the influence of sphingolipid mass on retention time, and generate two-dimensional plots that facilitate accurate visualization and characterization of the different ceramide moieties within a given sphingolipid class, because related molecules align horizontally or vertically on the plots. Major brain GalCer species that differ in mass by only 0.04 Da were easily differentiated on the basis of their hydrophobicity. The importance of our method\u27s capacity to define all of the major GalCer species in the brain samples is illustrated by the novel observation that the proportion of GalCer with hydroxylated fatty acids increased approximately 2-fold in the hippocampus of AD patients, compared with age- and gender-matched controls. This suggests activation of fatty acid hydroxylase in AD. Our method greatly improves the clarity of data obtained in a lipid profiling experiment and can be expanded to other lipid classes

Leonard et al._OIKOS_2018

Sheet 1 (Absolute conditioning): Absolute PER conditioning protocol using 6 conditioning trials. Conditioned stimulus (predictor variable) included 8 volatiles (linalool, dipentene, myrcene, geranium, linalool and petrol pollution, dipentene and petrol pollution, myrcene and petrol pollution, geranium and petrol pollution). Response variable = proboscis extension (binary response following exposure to conditioned stimuli: 0 no proboscis extension, 1 proboscis extension). Sheet 2 (Recall tests): Proboscis extension following exposure to 1 of 8 conditioned stimuli (linalool, dipentene, myrcene, geranium, linalool and petrol pollution, dipentene and petrol pollution, myrcene and petrol pollution, geranium and petrol pollution), 1 hr, 24 hrs and 48 hrs post conditioning. Response to conditioned stimuli and conditioned stimuli with or without the addition of petrol exhaust pollution was recorded

Selective displacement of a scorpionand triazole ligand from metallocyclam complexes visualised using NMR spectroscopy.

Target-activated metal complexes (TAMCs) – complexes that remain benign until reaching a specific biomolecular target, binding to which then affects structural change that turns on cytotoxicity or other activity – hold considerable allure. The successful development of TAMCs requires analytical methods that allow clear and unequivocal visualisation of changes in the coordination geometry of these systems in solution. Towards this goal, we report an NMR-based method to monitor coordination/ de-coordination of a pendant triazole ligand to/ from metal-cyclam complexes of zinc(II) and mercury(II). This scorpionand ligand can be displaced from the metal, which remains bound to the macrocyclic ligand, using an appropriate competing ligand: chloride for the mercury(II) complexes, piperidine or citrate at zinc(II). Triazole displacement may be visualised by monitoring the 1H NMR resonance of the single triazole C–H proton environment. Using 2H NMR with a specifically deuterated complex enables the same change to be monitored in a noisy 1H landscape, as would be encountered at a protein binding site or other biological context. MALDI-TOF mass spectrometry experiments provide confirmation that the changes observed by NMR spectroscopy are due to changes in triazole coordination, rather than stripping of the metal ion from the complex

Studies of the labile lead pool using a rhodamine-based fluorescent probe

Lead is a heavy metal which has long been known to have toxic effects on the body. However, much remains to be learnt about the labile lead pool and cellular uptake of lead. We report here RPb1 that undergoes a 100-fold increase in fluorescence emission in the presence of Pb2+, and which can be applied to study the labile lead pool within cells. We demonstrate the capacity of RPb1 for investigating labile lead pool in DLD-1 cells and changes in labile lead during differentiation of K562 cells

Data from: Olfactory and visual plant cues as drivers of selective herbivory

Food quality is an important consideration in the foraging strategy of all animals, including herbivores. Those that can detect and assess the nutritional value of plants from afar, using senses such as smell and sight, can forage more efficiently than those that must assess food quality by taste alone. Selective foraging not only affects herbivore fitness but can influence the structure and composition of plant communities, yet little is known about how olfactory and visual cues help herbivores to find preferred plants. We tested the ability of a free-ranging, generalist mammalian browser, the swamp wallaby Wallabia bicolor, to use olfactory and visual plant cues to find and/or browse differentially on Eucalyptus pilularis seedlings grown under different nutrient conditions. Low-nutrient seedlings differed from high-nutrient seedlings, having lighter coloured leaves, red stems and lower biomass and nitrogen content. In the absence of visual cues, wallabies used odour to differentiate vials containing cut seedlings. They visited and investigated patches with high-nutrient seedling odour most, followed by patches with low-nutrient seedling odour, and patches with no added odour least. However, when visual and olfactory cues of seedlings were present, wallabies reversed their foraging response and were more likely to browse low- than high-nutrient seedlings. This browsing difference, in turn, disappeared when long-range visual cues were reduced by pinning seedlings horizontal to the ground. We suggest that visual cues overrode the effects of olfactory cues on browsing patterns of intact seedlings. Our study shows that herbivores can respond to odours of higher nutrient plants but in ecologically realistic scenarios they use a variety of visual and olfactory cues, with a context-dependent outcome that is not always selection of high nutrient food. Our results demonstrate the importance of testing the sensory abilities of herbivores in realistic multi-sensory settings to understand their function in selective foraging

Extraction and transport of sulfate using macrocyclic squaramide receptors

The selective extraction of the hydrophilic sulfate ion from water is highly challenging because the high free energy of hydration of this ion makes it more difficult to extract than less hydrophilic ions such as chloride and nitrate. Lipophilic macrocyclic squaramide receptors 1 and 2 were synthesized. Receptor 2 efficiently extracted sulfate from aqueous sodium sulfate solutions into a chloroform phase, via exchange with nitrate ions, overcoming the Hofmeister bias. The resulting 2$SO4 2� complex was readily recycled through precipitation of BaSO4. Transport of sulfate across a bulk chloroform membrane by 2 was demonstrated across a wide pH range (pH 3.2–9.4) and in the presence of high concentrations of competing anions (chloride, nitrate and dihydrogenphosphate), opening the door to the use of 2 for the selective removal of sulfate from water across a range of applications

Changes in the in vitro activity of platinum drugs when administered in two aliquots

Background: The management of ovarian cancer remains a challenge. Because of the lack of early symptoms, it is often diagnosed at a late stage when it is likely to have metastasized beyond ovaries. Currently, platinum based chemotherapy is the primary treatment for the disease. However acquired drug resistance remains an on-going problem. As cisplatin brings about apoptosis by intrinsic and extrinsic pathways, this study aimed to determine changes in activity of platinum drugs when administered in two aliquots as against a bolus and sought to determine association with changes in GSH, speciation of platinum drugs and changes in protein expression. Methods: The efficacy of administering cisplatin, carboplatin and oxaliplatin in two aliquots with a time gap was investigated in ovarian A2780, A2780(cisR), A2780(ZD0473R) and SKOV-3 cell lines. The cellular accumulation of platinum, level of platinum - DNA binding and cellular glutathione level were determined, and proteomic studies were carried out to identify key proteins associated with platinum resistance in ovarian A2780(cisR) cancer cell line. Results: Much greater cell kill was observed with solutions left standing at room temperature than with freshly prepared solutions, indicating that the increase in activity on ageing was related to speciation of the drug in solution. Proteomic studies identified 72 proteins that were differentially expressed in A2780 and A2780(cisR) cell lines; 22 of them were restored back to normal levels as a result of synergistic treatments, indicating their relevance in enhanced drug action. Conclusions: The proteins identified are relevant to several different cellular functions including invasion and metastasis, cell cycle regulation and proliferation, metabolic and biosynthesis processes, stress-related proteins and molecular chaperones, mRNA processing, cellular organization/cytoskeleton, cellular communication and signal transduction. This highlights the multifactorial nature of platinum resistance in which many different proteins with diverse functions play key roles. This means multiple strategies can be harnessed to overcome platinum resistance in ovarian cancer. The results of the studies can be significant both from fundamental and clinical view points.25 page(s