Control of magnetic anisotropy by orbital hybridization in (La0.67Sr0.33MnO3)n/(SrTiO3)n superlattice

The asymmetry of chemical nature at the hetero-structural interface offers an unique opportunity to design desirable electronic structure by controlling charge transfer and orbital hybridization across the interface. However, the control of hetero-interface remains a daunting task. Here, we report the modulation of interfacial coupling of (La0.67Sr0.33MnO3)n/(SrTiO3)n superlattices by manipulating the periodic thickness with n unit cells of SrTiO3 and n unit cells La0.67Sr0.33MnO3. The easy axis of magnetic anisotropy rotates from in-plane (n = 10) to out-of-plane (n = 2) orientation at 150 K. Transmission electron microscopy reveals enlarged tetragonal ratio > 1 with breaking of volume conservation around the (La0.67Sr0.33MnO3)n/(SrTiO3)n interface, and electronic charge transfer from Mn to Ti 3d orbitals across the interface. Orbital hybridization accompanying the charge transfer results in preferred occupancy of 3d3z2-r2 orbital at the interface, which induces a stronger electronic hopping integral along the out-of-plane direction and corresponding out-of-plane magnetic easy axis for n = 2. We demonstrate that interfacial orbital hybridization in superlattices of strongly correlated oxides may be a promising approach to tailor electronic and magnetic properties in device applications

Ellipsoidal analysis of coordination polyhedra

The idea of the coordination polyhedron is essential to understanding chemical structure. Simple polyhedra in crystalline compounds are often deformed due to structural complexity or electronic instabilities so distortion analysis methods are useful. Here we demonstrate that analysis of the minimum bounding ellipsoid of a coordination polyhedron provides a general method for studying distortion, yielding parameters that are sensitive to various orders in metal oxide examples. Ellipsoidal analysis leads to discovery of a general switching of polyhedral distortions at symmetry-disallowed transitions in perovskites that may evidence underlying coordination bistability, and reveals a weak off-centre ‘d(5) effect' for Fe(3+) ions that could be exploited in multiferroics. Separating electronic distortions from intrinsic deformations within the low temperature superstructure of magnetite provides new insights into the charge and trimeron orders. Ellipsoidal analysis can be useful for exploring local structure in many materials such as coordination complexes and frameworks, organometallics and organic molecules

PPARδ Activation Acts Cooperatively with 3-Phosphoinositide-Dependent Protein Kinase-1 to Enhance Mammary Tumorigenesis

Peroxisome proliferator-activated receptorδ (PPARδ) is a transcription factor that is associated with metabolic gene regulation and inflammation. It has been implicated in tumor promotion and in the regulation of 3-phosphoinositide-dependent kinase-1 (PDK1). PDK1 is a key regulator of the AGC protein kinase family, which includes the proto-oncogene AKT/PKB implicated in several malignancies, including breast cancer. To assess the role of PDK1 in mammary tumorigenesis and its interaction with PPARδ, transgenic mice were generated in which PDK1 was expressed in mammary epithelium under the control of the MMTV enhancer/promoter region. Transgene expression increased pT308AKT and pS9GSK3β, but did not alter phosphorylation of mTOR, 4EBP1, ribosomal protein S6 and PKCα. The transgenic mammary gland also expressed higher levels of PPARδ and a gene expression profile resembling wild-type mice maintained on a diet containing the PPARδ agonist, GW501516. Both wild-type and transgenic mice treated with GW501516 exhibited accelerated rates of tumor formation that were more pronounced in transgenic animals. GW501516 treatment was accompanied by a distinct metabolic gene expression and metabolomic signature that was not present in untreated animals. GW501516-treated transgenic mice expressed higher levels of fatty acid and phospholipid metabolites than treated wild-type mice, suggesting the involvement of PDK1 in enhancing PPARδ-driven energy metabolism. These results reveal that PPARδ activation elicits a distinct metabolic and metabolomic profile in tumors that is in part related to PDK1 and AKT signaling

A systematic review of patient reported factors associated with uptake and completion of cardiovascular lifestyle behaviour change

Background: Healthy lifestyles are an important facet of cardiovascular risk management. Unfortunately many individuals fail to engage with lifestyle change programmes. There are many factors that patients report as influencing their decisions about initiating lifestyle change. This is challenging for health care professionals who may lack the skills and time to address a broad range of barriers to lifestyle behaviour. Guidance on which factors to focus on during lifestyle consultations may assist healthcare professionals to hone their skills and knowledge leading to more productive patient interactions with ultimately better uptake of lifestyle behaviour change support. The aim of our study was to clarify which influences reported by patients predict uptake and completion of formal lifestyle change programmes. Methods: A systematic narrative review of quantitative observational studies reporting factors (influences) associated with uptake and completion of lifestyle behaviour change programmes. Quantitative observational studies involving patients at high risk of cardiovascular events were identified through electronic searching and screened against pre-defined selection criteria. Factors were extracted and organised into an existing qualitative framework. Results: 374 factors were extracted from 32 studies. Factors most consistently associated with uptake of lifestyle change related to support from family and friends, transport and other costs, and beliefs about the causes of illness and lifestyle change. Depression and anxiety also appear to influence uptake as well as completion. Many factors show inconsistent patterns with respect to uptake and completion of lifestyle change programmes. Conclusion: There are a small number of factors that consistently appear to influence uptake and completion of cardiovascular lifestyle behaviour change. These factors could be considered during patient consultations to promote a tailored approach to decision making about the most suitable type and level lifestyle behaviour change support

Tyrosine kinase signalling in breast cancer: Fibroblast growth factors and their receptors

The fibroblast growth factors [Fgfs (murine), FGFs (human)] constitute a large family of ligands that signal through a class of cell-surface tyrosine kinase receptors. Fgf signalling has been associated in vitro with cellular differentiation as well as mitogenic and motogenic responses. In vivo, Fgfs are critical for animal development, and some have potent angiogenic properties. Several Fgfs have been identified as oncogenes in murine mammary cancer, where their deregulation is associated with proviral insertions of the mouse mammary tumour virus (MMTV). Thus, in some mammary tumours of MMTV-infected mouse strains, integration of viral genomic DNA into the somatic DNA of mammary epithelial cells was found to have caused the inappropriate expression of members of this family of growth factors. Although examination of human breast cancers has shown an altered expression of FGFs or of their receptors in some tumours, their role in the causation of breast disease is unclear and remains controversial

Randomised controlled trial on the effectiveness of home-based walking exercise on anxiety, depression and cancer-related symptoms in patients with lung cancer

© 2015 Cancer Research UK. All rights reserved 0007 - 0920/15.Background:Although exercise has been addressed as an adjuvant treatment for anxiety, depression and cancer-related symptoms, limited studies have evaluated the effectiveness of exercise in patients with lung cancer.Methods:We recruited 116 patients from a medical centre in northern Taiwan, and randomly assigned them to either a walking-exercise group (n=58) or a usual-care group (n=58). We conducted a 12-week exercise programme that comprised home-based, moderate-intensity walking for 40 min per day, 3 days per week, and weekly exercise counselling. The outcome measures included the Hospital Anxiety and Depression Scale and the Taiwanese version of the MD Anderson Symptom Inventory.Results:We analysed the effects of the exercise programme on anxiety, depression and cancer-related symptoms by using a generalised estimating equation method. The exercise group patients exhibited significant improvements in their anxiety levels over time (P=0.009 and 0.006 in the third and sixth months, respectively) and depression (P=0.00006 and 0.004 in the third and sixth months, respectively) than did the usual-care group patients.Conclusions:The home-based walking exercise programme is a feasible and effective intervention method for managing anxiety and depression in lung cancer survivors and can be considered as an essential component of lung cancer rehabilitation.Link_to_subscribed_fulltex