Unusual η2‐Allene Osmacycle with Apoptotic Properties

Screening of a library of structurally unusual osmacyclic complexes for their antiproliferate properties in HeLa cells led to the discovery of a highly cytotoxic η²‐allene osmacycle. In this remarkably stable complex, osmium constitutes part of a metallacycle through the formation of a σ‐bond to a carbon in combination with coordination to an allene moiety. The osmacycle strongly induces apoptosis in Burkitt‐like lymphoma cells at submicromolar concentrations. The reduction of the mitochondrial membrane potential, the induction of DNA fragmentation, and the activation of caspases‐9 and ‐3 reveal that programmed cell death occurs through the intrinsic mitochondrial pathway. From the lipophilic and cationic nature of the osmacycle, in addition to a low oxidation potential (E_1/2=+0.27 V vs. Fc/Fc⁺, Fc=ferrocene) it is proposed that mitochondria are the cellular target where oxidative decomposition initiates apoptosis.     

Kinetic study of the oxidation resistance of phosphorus-containing activated carbons

Chemical activation of different lignocellulosic materials with phosphoric acid produces activated carbons with higher oxidation resistance than that observed for catalyst free chars obtained at similar conditions from the same biomass, even though the activated carbons have a more developed porous structure. The main reason for such behavior is probably related to the presence of thermally stable phosphorus complexes that remain on the carbon surface after the activation process. XPS analyses point out the oxidation of the phosphorus reduced groups to C–O–PO₃/(CO)₂PO₂ prior to carbon gasification. The latter complexes seem to stabilize the active carbon sites. Moreover, the presence of these phosphorus inhibitors produces a change in the gasification mechanism of the activated carbons with respect to that for char. Char oxidation seems to proceed in the entire available particle surface, while activated carbon gasification is better explained by the shrinking unreacted core model. Such a difference in mechanism is attributed to the inhibition effect of the phosphorus complexes, which reduces the reactivity of carbon active sites, and could act as a physical barrier for oxygen diffusion in the micropores.     

Reclaim of the By-Products from “Horchata” Elaboration Process

The recovery of effluents for different uses is an interesting practice that can contribute to a better management of water resources all over the world. Tiger nuts or “chufa” (Cyperus esculentus) are tubers mainly used to produce “horchata de chufa” (tiger nuts milk), yielding a high quantity of co-products (solids and liquids). The composition of these co-products makes them suitable for other uses. The aim of this work was to study the composition, microbial quality, physicochemical properties, and antioxidant activity of the “horchata” drained-water. The obtained results prove that “horchata” drained-water could be considered a valuable source of natural antioxidants. A good correlation between total phenol content and reducing power, rancimat performance, and inhibition of lipid peroxidation of buffered egg yolk assays supports the idea that phenols may be the main contributors to the antioxidant power of “horchata” drained-water. However, its microbial quality is poor, so this liquid residue must be heat-treated before its addition to any food product.     

Influence of the spinning rate in the HR-MAS pattern of mobile lipids in C6 glioma cells and in artificial oil bodies

Object

To evaluate how spinning rate affects mobile lipid (ML) resonances visibility in HR-MAS spectra of C6 glioma cells and artificial oil bodies (AOB), as models of cytosolic lipid droplets.

Materials and methods

Using C6 cells and AOB of two different sizes, 780?±?580 and 240?±?293?nm, as models, we acquired HR-MAS pulse and acquire spectra at different spinning rates between 500 and 15,000?Hz, all at 37?°C.

Results

Sample spinning at 15,000?Hz increased by 2.3 and 4.6-fold with respect to 500?Hz spinning the area of resonances corresponding to ML at 0.88 and 1.28?ppm, respectively, for log phase C6 cells. Furthermore, postconfluent C6 cells displayed an increase of 2.5-fold at 0.88?ppm and 4.2-fold at 1.28?ppm. These changes were reversible upon low speed spinning. AOBs did show much lower ML area increases (1.4?C1.5-fold) upon high-speed HR-MAS.

Conclusion

ML can be reversibly mobilized in C6 glioma cells by high-speed HR-MAS, partially unveiling the NMR ??invisible?? ML pool. A small part of the ML pool also shows reduced visibility in freely tumbling AOBs.     

Thymic epithelial cells as a diagnostic pitfall in the fine-needle aspiration diagnosis of primary mediastinal lymphoma

This paper reports data on the effect of a new antioxidant, U-83836E, on the lipid peroxidation and antioxidant status of liver, red blood cells (RBCs) and blood serum of rats intoxicated with methanol (3.0 g/kg body weight). Methanol administration slightly increased the levels of peroxidation products in the liver, and markedly increased them in RBCs and serum. In contrast, glutathione-peroxidase, glutathione-reductase activity, reduced glutathione concentration and total antioxidant status were decreased. The use of U-83836E, containing a trolox ring, appeared to be beneficial in reducing lipid peroxidation products and in partially in preventing the decrease in glutathione and antioxidant enzymes induced by methanol in liver and serum. These results show that antioxidant U-83836E may partially prevent methanol toxicity.     

Lignocellulosic-derived catalysts for the selective oxidation of propane

The formation of dispersed VPO phases on a lignocellulosic-based activated carbon results in a catalyst that is selective for the partial oxidation of propane, and stable under oxidizing conditions. The use of a stable activated carbon as a catalytic support for active VOx species during the partial oxidation of propane is described for the first time.     

Managing Irrigation Water Shortage: a Comparison Between Five Allocation Rules Based on Crop Benefit Functions

In this work the efficiency of five allocation rules of irrigation water is analyzed and compared. We define the most efficient rule as the one that minimizes the economic losses arising from a reduction in water availability. The first allocation rule is an equal quota granted to all irrigators. The second one is based on proportional reductions. By means of the third rule all losses of income per hectare are matched, while the fourth makes that all relative losses to the reference incomes are matched. Lastly the fifth rule seeks to maximize private benefit and economic efficiency. We prove that this one would likely be preferred by farmers growing more than one crop. The fundamentals of these rules are included, showing the analytical deduction of the crop-specific reallocations from any prescribed water reduction rule within an irrigation district, as well as the losses of income ensuing from reduced water deliveries. The methodology used herein to compare the efficiency of all these rules is dependent on the relations between allocations and yields. To estimate them, a simple and practical procedure is presented. The five allocation rules are applied to an irrigation community and compared to each other in terms of economic efficiency. Differences in economic losses arising from one rule or another will be sharper the more heterogeneous communities are. Different losses across rules will also be related to the level of water shortage.