Apparent histological changes of adipocytes after treatment with CL 316,243, a β-3-adrenergic receptor agonist

Background and objectives: The objective of this experiment was to study the effect of CL 316,243 (CL) (a highly selective β3-adrenergic receptor agonist) on cellular changes occurring in retroperitoneal white adipose tissue (RWAT) of lean and obese rats.Methods: Ten-month-old lean and obese Zucker rats were implanted subcutaneously with osmotic mini-pumps, infusing either saline or CL (1 mg/kg body weight/day) for 4 weeks. Results: There was no effect of CL on food intake. However, the resting metabolic rate in lean and obese rats increased by 55 and 96 per rat, respectively. Total RWAT weight decreased in both lean and obese rats under influence of CL treatment by 65 and 38, respectively. Total body weight and body fat were lower in CL treated rats. Detection of uncoupling protein 1 (UCP1) in RWAT was confirmed qualitatively by both immunohistochemistry and immunofluorescence using a rabbit anti rat UCP1 antibody which showed the appearance of a marked increase of this protein in the adipose tissue. Stained semi-thin sections (0.5 µm) also demonstrated abundant nuclei in multilocular adipocytes, in endothelial cells associated with the vasculature, and in interstitial cells. In CL-treated obese rats, a clustering of several multilocular cells around the periphery of a white adipocyte was seen.Conclusion: These results indicate that treatment of both lean and obese Zucker rats with CL induces extensive remodeling of RWAT that includes shrinkage of white adipose tissue, appearance of abundant multilocular cells in RWAT together with the appearance of a marked increase of UCP, preferentially in lean rats. © 2015 Ghorbani et al

Up to 40 % reduction of the GaAs band gap energy via strain engineering in core/shell nanowires

The great possibilities for strain engineering in core/shell nanowires have been explored as an alternative route to tailor the properties of binary III-V semiconductors without changing their chemical composition. In particular, we demonstrate that the GaAs core in GaAs/In(x)Ga(1-x)As or GaAs/In(x)Al(1-x)As core/shell nanowires can sustain unusually large misfit strains that would have been impossible in conventional thin-film heterostructures. The built-in strain in the core can be regulated via the composition and the thickness of the shell. Thick enough shells become almost strain-free, whereas the thin core undergoes a predominantly-hydrostatic tensile strain, which causes the reduction of the GaAs band gap energy. For the highest strain of 7 % in this work (obtained for x=0.54), a remarkable reduction of the band gap by 40 % was achieved in agreement with theoretical calculations. Such strong modulation of its electronic properties renders GaAs suitable for near-infrared nano-photonics and presumably high electron mobility nano-transistors.Comment: 12 pages, 4 figure

Effects of L-asparginase administration on anticoagulant proteins and platelet function in patients with acute lymphoblastic leukemia

Introduction: Acute lymphoblastic leukemia is one the most common malignancies in children and adolescents. L-asparginase (L-ASP) is one of the leading medications in treatment of ALL. L.ASP interferes with the synthesis of some coagulation proteins and therefore causing disturbance in normal coagulation. In this study, the effects of L-ASP on anticoagulant proteins (protein C, protein S, and antithrombin III) and platelet function were assessed. Material and methods: This was a before-after study on 41 patients with ALL who refered to Mahak hospital (Tehran, Iran). Before and after the injection of L.ASP, a bleeding time test was performed based on Ivy method. Protein C and protein S performance was assessed by turbidometry and antithrombin III performance was evaluated by chromogenic method. Results: 48.8 of patients were female. Mean (±SD) of age was 4.0±7.2. A significant reduction in the mean amount of protein C, antithrombin III and bleeding time was recorded. However, the reduction in protein S was not significant. No patient showed the symptoms of thrombosis. Conclusion: The results of this study showed that L. ASP drug reduced coagulation proteins (except the protein S). This decrease along with other concomitant genetic factors can lead to thrombosis in some patients with ALL during induction therapy

Free-Standing Hierarchically Sandwich-Type Tungsten Disulfide Nanotubes/Graphene Anode for Lithium-Ion Batteries

Transition metal dichalcogenides (TMD), analogue of graphene, could form various dimensionalities. Similar to carbon, one dimensional (1D) nanotube of TMD materials has wide application in hydrogen storage，Li-ion batteries and supercapacitors due to their unique structure and properties. Here we demonstrate the feasibility of tungsten disulfide nanotubes (WS2-NTs)/graphene (GS) sandwich-type architecture as anode for lithium-ion batteries for the first time. The graphene based hierarchical architecture plays vital roles in achieving fast electron/ion transfer, thus leading to good electrochemical performance. When evaluated as anode, WS2-NTs /GS hybrid could maintain a capacity of 318.6 mA/g over 500 cycles at a current density of 1A/g. Besides, the hybrid anode does not require any additional polymetric binder, conductive additives or a separate metal current-collector. The relatively high density of this hybrid is beneficial for high capacity per unit volume. Those characteristics make it a potential anode material for light and high performance lithium-ion batteries

Electron beam-formed ferromagnetic defects on MoS2 surface along 1T phase transition

1 T phase incorporation into 2H-MoS2 via an optimal electron irradiation leads to induce a weak ferromagnetic state at room temperature, together with the improved transport property. In addition to the 1T-like defects, the electron irradiation on the cleaved MoS2 surface forms the concentric circletype defects that are caused by the 2 H/1 T phase transition and the vacancies of the nearby S atoms of the Mo atoms. The electron irradiation-reduced bandgap is promising in vanishing the Schottky barrier to attaining spintronics device. The simple method to control and improve the magnetic and electrical properties on the MoS2 surface provides suitable ways for the low-dimensional device applications.ope

Local strain engineering in atomically thin MoS2

Tuning the electronic properties of a material by subjecting it to strain constitutes an important strategy to enhance the performance of semiconducting electronic devices. Using local strain, confinement potentials for excitons can be engineered, with exciting possibilities for trapping excitons for quantum optics and for efficient collection of solar energy. Two-dimensional materials are able to withstand large strains before rupture, offering a unique opportunity to introduce large local strains. Here, we study atomically thin MoS2 layers with large local strains of up to 2.5% induced by controlled delamination from a substrate. Using simultaneous scanning Raman and photoluminescence imaging, we spatially resolve a direct bandgap reduction of up to 90 meV induced by local strain. We observe a funnel effect in which excitons drift hundreds of nanometers to lower bandgap regions before recombining, demonstrating exciton confinement by local strain. The observations are supported by an atomistic tight-binding model developed to predict the effect of inhomogeneous strain on the local electronic states in MoS2. The possibility of generating large strain-induced variations in exciton trapping potentials opens the door for a variety of applications in atomically thin materials including photovoltaics, quantum optics and two-dimensional optoelectronic devices.Comment: Supp.Info. not included here, available following a link included in the tex

Apparent histological changes of adipocytes after treatment with CL 316,243, a ß-3-adrenergic receptor agonist

Masoud Ghorbani,1,2,* Shahram Teimourian,3,* Reza Farzad,4 Nabiollah Namvar Asl4 1Research and Development Department, Pasteur Institute of Iran, Tehran, Iran; 2Department of Biochemistry, University of Ottawa, Ottawa, ON, Canada; 3Department of Medical Genetics, Iran University of Medical Sciences, Tehran, Iran; 4Department of Animal Science, Pasteur Institute of Iran, Research and Production Complex, Karaj, Iran*These authors contributed equally to this work Background and objectives: The objective of this experiment was to study the effect of CL 316,243 (CL) (a highly selective ß3-adrenergic receptor agonist) on cellular changes occurring in retroperitoneal white adipose tissue (RWAT) of lean and obese rats. Methods: Ten-month-old lean and obese Zucker rats were implanted subcutaneously with osmotic mini-pumps, infusing either saline or CL (1 mg/kg body weight/day) for 4 weeks. Results: There was no effect of CL on food intake. However, the resting metabolic rate in lean and obese rats increased by 55% and 96% per rat, respectively. Total RWAT weight decreased in both lean and obese rats under influence of CL treatment by 65% and 38%, respectively. Total body weight and body fat were lower in CL treated rats. Detection of uncoupling protein 1(UCP1) in RWAT was confirmed qualitatively by both immunohistochemistry and immunofluorescence using a rabbit anti rat UCP1 antibody which showed the appearance of a marked increase of this protein in the adipose tissue. Stained semi-thin sections (0.5 µm) also demonstrated abundant nuclei in multilocular adipocytes, in endothelial cells associated with the vasculature, and in interstitial cells. In CL-treated obese rats, a clustering of several multilocular cells around the periphery of a white adipocyte was seen. Conclusion: These results indicate that treatment of both lean and obese Zucker rats with CL induces extensive remodeling of RWAT that includes shrinkage of white adipose tissue, appearance of abundant multilocular cells in RWAT together with the appearance of a marked increase of UCP, preferentially in lean rats. Keywords: brown adipose tissue, cellularity of adipose tissue, obesity, thermogenesis, uncoupling protein, Zucker rat