In Vivo Low-level Light Therapy Increases Cytochrome Oxidase in Skeletal Muscle

Low-level light therapy (LLLT) increases survival of cultured cells, improves behavioral recovery from neurodegeneration and speeds wound healing. These beneficial effects are thought to be mediated by upregulation of mitochondrial proteins, especially the respiratory enzyme cytochrome oxidase. However, the effects of in vivo LLLT on cytochrome oxidase in intact skeletal muscle have not been previously investigated. We used a sensitive method for enzyme histochemistry of cytochrome oxidase to examine the rat temporalis muscle 24 h after in vivo LLLT. The findings showed for the first time that in vivo LLLT induced a dose- and fiber type-dependent increase in cytochrome oxidase in muscle fibers. LLLT was particularly effective at enhancing the aerobic capacity of intermediate and red fibers. The findings suggest that LLLT may enhance the oxidative energy metabolic capacity of different types of muscle fibers, and that LLLT may be used to enhance the aerobic potential of skeletal muscle.     

trans-Platinum planar amine compounds with [N2O2] ligand donor sets: effects of carboxylate leaving groups and steric hindrance on chemical and biological properties

Replacement of NH3 by a planar amine L to give trans-[PtCl2(L)(L')] (L = NH3, L'= pyridine or substituted pyridine, quinoline, isoquinoline, thiazole; L = L'= pyridine, thiazole), greatly enhances the cytotoxicity of the transplatinum geometry. The "parent" compound trans-[PtCl2(NH3)2] is therapeutically inactive. Modification of the ligands to an [N2O2] donor set, where O represents an acetate leaving group, enhances the aqueous solubility while retaining the cytotoxicity of the parent chloride compounds. The effect of two mutual trans leaving groups with weak trans influence is to impart remarkable chemical stability on the structure. This strategy is analogous to the use of the inert dicarboxylate leaving groups in the clinical compounds carboplatin and oxaliplatin. In this paper, systematic modification of the steric effects of carrier pyridine groups and, especially, carboxylate leaving groups in trans-[Pt(O2CR)2(NH3)(pyr)] is shown to modulate aqueous solubility and hydrolysis to the activated aqua species. The results presented here demonstrate the utility of the "carboxylate strategy" in "fine-tuning" the chemical and pharmacokinetic properties in the design of clinically relevant transplatinum complexes.     

Ferrocene embedded in an electrode-supported hybrid lipid bilayer membrane: a model system for electrocatalysis in a biomimetic environment

An electrode-supported system in which ferrocene molecules are embedded in a hybrid bilayer membrane (HBM) has been prepared and characterized. The redox properties of the ferrocene molecules were studied by varying the lipid and alkanethiol building blocks of the HBM. The midpoint potential and electron transfer rate of the embedded ferrocene were found to be dependent on the hydrophobic nature of the electrolyte and the distance at which the ferrocene was positioned in the HBM relative to the electrode and the solution. Additionally, the ability of the lipid-embedded ferrocenium ions to oxidize solution phase ascorbic acid was evaluated and found to be dependent on the nature of the counterion.     

On the comparison of semi-analytical methods for the stability analysis of delay differential equations

This paper provides the first comparison of the semi-discretization, spectral element, and Legendre collocation methods. Each method is a technique for solving delay differential equations (DDEs) as well as determining regions of stability in the DDE parameter space. We present the necessary concepts, assumptions, and equations required to implement each method. To compare the relative performance between the methods, the convergence rate and computational time for each method is compared in three numerical studies consisting of a ship stability example, the delayed damped Mathieu equation, and a helicopter rotor control problem. For each study, we present one or more stability diagrams in the parameter space and one or more convergence plots. The spectral element method is demonstrated to have the quickest convergence rate while the Legendre collocation method requires the least computational time. The semi-discretization method on the other hand has both the slowest convergence rate and requires the most computational time.     

Incompressible surfaces and spunnormal form

Suppose M is a cusped finite-volume hyperbolic 3-manifold and T{\mathcal{T}} is an ideal triangulation of M with essential edges. We show that any incompressible surface S in M that is not a virtual fiber can be isotoped into spunnormal form in T{\mathcal{T}}. The proof is based directly on ideas of W. Thurston.     

Mechanistic Insights into the Luminescent Sensing of Organophosphorus Chemical Warfare Agents and Simulants Using Trivalent Lanthanide Complexes

Organophosphorus chemical warfare agents (OP CWAs) are potent acetylcholinesterase inhibitors that can cause incapacitation and death within minutes of exposure, and furthermore are largely undetectable by the human senses. Fast, efficient, sensitive and selective detection of these compounds is therefore critical to minimise exposure. Traditional molecular‐based sensing approaches have exploited the chemical reactivity of the OP CWAs, whereas more recently supramolecular‐based approaches using non‐covalent interactions have gained momentum. This is due, in part, to the potential development of sensors with second‐generation properties, such as reversibility and multifunction capabilities. Supramolecular sensors also offer opportunities for incorporation of metal ions allowing for the exploitation of their unique properties. In particular, trivalent lanthanide ions are being increasingly used in the OP CWA sensing event and their use in supramolecular sensors is discussed in this Minireview. We focus on the fundamental interactions of simple lanthanide systems with OP CWAs and simulants, along with the development of more elaborate and complex systems including those containing nanotubes, polymers and gold nanoparticles. Whilst literature investigations into lanthanide‐based OP CWA detection systems are relatively scarce, their unique and versatile properties provide a promising platform for the development of more efficient and complex sensing systems into the future.