Opioids do not influence metastasis in experimental animal cancer models

Correspondenc

Moving Difference (MDIFF) Non-adiabatic Rapid Sweep (NARS) EPR of Copper(II)

Non-adiabatic rapid sweep (NARS) EPR spectroscopy has been introduced for application to nitroxide-labeled biological samples (Kittell et al., 2011). Displays are pure absorption, and are built up by acquiring data in spectral segments that are concatenated. In this paper we extend the method to frozen solutions of copper-imidazole, a square planar copper complex with four in-plane nitrogen ligands. Pure absorption spectra are created from concatenation of 170 5-gauss segments spanning 850 G at 1.9 GHz. These spectra, however, are not directly useful since nitrogen superhyperfine couplings are barely visible. Application of the moving difference (MDIFF) algorithm to the digitized NARS pure absorption spectrum is used to produce spectra that are analogous to the first harmonic EPR. The signal intensity is about four times higher than when using conventional 100 kHz field modulation, depending on line shape. MDIFF not only filters the spectrum, but also the noise, resulting in further improvement of the SNR for the same signal acquisition time. The MDIFF amplitude can be optimized retrospectively, different spectral regions can be examined at different amplitudes, and an amplitude can be used that is substantially greater than the upper limit of the field modulation amplitude of a conventional EPR spectrometer, which improves the signal-to-noise ratio of broad lines

Dalbavancin in the treatment of complicated skin and soft-tissue infections: a review

Increasing rates of antimicrobial resistance among strains of Streptococcus, Staphylococcus, and Enterococcus spp. have been widely documented. At least 50% of nosocomial Staphylococcus aureus infections in intensive care units in the US and UK are due methicillin-resistant S. aureus (MRSA). Drug resistance is not confined to hospitals, and community-acquired MRSA (CA-MRSA) strains are now common causes of complicated skin and soft-tissue infections (cSSTIs) in many regions. Dalbavancin is a novel parenterally administered semisynthetic lipoglycopeptide similar to the naturally produced glycopeptides vancomycin and teicoplanin. Dalbavancin features a multifaceted mechanism of action that inhibits bacterial cell wall formation by two different mechanisms that enhances its activity against a wide range of gram-positive bacteria including staphylococci, streptococci, enterococci, and some anaerobes. Additionally, dalbavancin possesses unique pharmacokinetic properties, the most significant of which is a long terminal half-life that allows for once weekly dosing. This attribute may prove to yield clinical and cost benefit. Overall, clinical trials indicate that dalbavancin is a safe, well-tolerated, and effective antimicrobial agent. In the largest investigation evaluating dalbavancin for the treatment of cSSTIs, it appeared to be as effective as linezolid. Dalbavancin, which is expected to receive FDA approval in 2008, appears to be a promising new antimicrobial agent for the treatment of cSSTIs

Policy responses to invasive native species: issues of social and private benefits and costs

Farm and catchment managers in Australia face decisions about controlling invasive native species (or scrub) which may infest agricultural land. The treatment of this land to remove the infestation and re-establish native pastures is likely to be expensive for landholders. Yet there are potential social benefits from such remediation and so a policy question arises of what to do to about facilitating such change. New South Wales state government legislation addresses this issue through regulations, and the Catchment Management Authorities are responsible for administering public funds to achieve associated natural resource improvements. However, the extent of the private costs and social benefits associated with such changes are not known, which precludes benefit-cost analyses using the traditional welfare economics framework. This paper reports results of a social and private economic analysis of the impacts of a typical infestation remediation decision. We show that for the landholder the private costs exceed the benefits achieved from increased livestock productivity. However, there are social benefits expressed by the willingness to pay by members of the local catchment community for improvements in native vegetation and biodiversity. When these social benefits are included, the economic analysis shows a positive social net benefit. This raises questions of how to reconcile the public and private accounting, and whether any changes to policies, regulations or procedures for natural resource management in New South Wales are warranted.Invasive native scrub, environmental values, choice modelling, financial, economic, Namoi catchment,

Potentially Diagnostic Electron Paramagnetic Resonance Spectra Elucidate the Underlying Mechanism of Mitochondrial Dysfunction in the Deoxyguanosine Kinase Deficient Rat Model of a Genetic Mitochondrial DNA Depletion Syndrome

A novel rat model for a well-characterized human mitochondrial disease, mitochondrial DNA depletion syndrome with associated deoxyguanosine kinase (DGUOK) deficiency, is described. The rat model recapitulates the pathologic and biochemical signatures of the human disease. The application of electron paramagnetic (spin) resonance (EPR) spectroscopy to the identification and characterization of respiratory chain abnormalities in the mitochondria from freshly frozen tissue of the mitochondrial disease model rat is introduced. EPR is shown to be a sensitive technique for detecting mitochondrial functional abnormalities in situ and, here, is particularly useful in characterizing the redox state changes and oxidative stress that can result from depressed expression and/or diminished specific activity of the distinct respiratory chain complexes. As EPR requires no sample preparation or non-physiological reagents, it provides information on the status of the mitochondrion as it was in the functioning state. On its own, this information is of use in identifying respiratory chain dysfunction; in conjunction with other techniques, the information from EPR shows how the respiratory chain is affected at the molecular level by the dysfunction. It is proposed that EPR has a role in mechanistic pathophysiological studies of mitochondrial disease and could be used to study the impact of new treatment modalities or as an additional diagnostic tool

Monolayer MoS2 strained to 1.3% with a microelectromechanical system

We report on a modified transfer technique for atomically thin materials integrated onto microelectromechanical systems (MEMS) for studying strain physics and creating strain-based devices. Our method tolerates the non-planar structures and fragility of MEMS, while still providing precise positioning and crack free transfer of flakes. Further, our method used the transfer polymer to anchor the 2D crystal to the MEMS, which reduces the fabrication time, increases the yield, and allowed us to exploit the strong mechanical coupling between 2D crystal and polymer to strain the atomically thin system. We successfully strained single atomic layers of molybdenum disulfide (MoS2) with MEMS devices for the first time and achieved greater than 1.3% strain, marking a major milestone for incorporating 2D materials with MEMS We used the established strain response of MoS2 Raman and Photoluminescence spectra to deduce the strain in our crystals and provide a consistency check. We found good comparison between our experiment and literature.Published versio

Time-, Frequency-, and Wavevector-Resolved X-Ray Diffraction from Single Molecules

Using a quantum electrodynamic framework, we calculate the off-resonant scattering of a broad-band X-ray pulse from a sample initially prepared in an arbitrary superposition of electronic states. The signal consists of single-particle (incoherent) and two-particle (coherent) contributions that carry different particle form factors that involve different material transitions. Single-molecule experiments involving incoherent scattering are more influenced by inelastic processes compared to bulk measurements. The conditions under which the technique directly measures charge densities (and can be considered as diffraction) as opposed to correlation functions of the charge-density are specified. The results are illustrated with time- and wavevector-resolved signals from a single amino acid molecule (cysteine) following an impulsive excitation by a stimulated X-ray Raman process resonant with the sulfur K-edge. Our theory and simulations can guide future experimental studies on the structures of nano-particles and proteins

Band Gap Engineering with Ultralarge Biaxial Strains in Suspended Monolayer MoS2

We demonstrate the continuous and reversible tuning of the optical band gap of suspended monolayer MoS2 membranes by as much as 500 meV by applying very large biaxial strains. By using chemical vapor deposition (CVD) to grow crystals that are highly impermeable to gas, we are able to apply a pressure difference across suspended membranes to induce biaxial strains. We observe the effect of strain on the energy and intensity of the peaks in the photoluminescence (PL) spectrum, and find a linear tuning rate of the optical band gap of 99 meV/%. This method is then used to study the PL spectra of bilayer and trilayer devices under strain, and to find the shift rates and Gr\"uneisen parameters of two Raman modes in monolayer MoS2. Finally, we use this result to show that we can apply biaxial strains as large as 5.6% across micron sized areas, and report evidence for the strain tuning of higher level optical transitions.Comment: Nano Lett., Article ASA