Depression Treatment: Surface Spin-Glass, Large Surface Anisotropy, and Depression of Magnetocaloric Effect in La(0.8)Ca(0.2)MnO(3) Nanoparticles.

Surface spin-glass, large surface anisotropy, and depression of magnetocaloric effect in La(0.8)Ca(0.2)MnO(3) nanoparticles.

Filed under: Depression Treatment

J Appl Phys. 2012 Dec 15; 112(12): 123903
Xi SB, Lu WJ, Wu HY, Tong P, Sun YP

The surface magnetic behavior of La(0.8)Ca(0.2)MnO(3) nanoparticles was investigated. We observed irreversibility in high magnetic field. The surface spin-glass behavior as well as the high-field irreversibility is suppressed by increasing particle size while the freezing temperature T(F) does not change with particle size. The enhanced coercivity has been observed in the particles and we attributed it to the large surface anisotropy. We have disclosed a clear relationship between the particle size, the thickness of the shell, and the saturation magnetization of the particles. The large reduction of the saturation magnetization of the samples is found to be induced by the increase of nonmagnetic surface large since the thickness of the spin-disordered surface layer increases with a decrease in the particle size. Due to the reduction of the magnetization, the magnetocaloric effect (MCE) has been reduced by the decreased particle size since the nonmagnetic surface contributes little to the MCE. Based on the core-shell structure, large relative cooling powers RCP(s) of 180?J/kg and 471?J/kg were predicted for a field change of 2.0?T and 4.5?T, respectively, in the small particles with thin spin-glass layer.
HubMed – depression

 

Excitation-induced exchange of Na+, K+, and Cl- in rat EDL muscle in vitro and in vivo: Physiology and pathophysiology.

Filed under: Depression Treatment

J Gen Physiol. 2013 Jan 14;
Clausen T

In skeletal muscle, excitation leads to increased [Na(+)](i), loss of K(+), increased [K(+)](o), depolarization, and Cl(-) influx. This study quantifies these changes in rat extensor digitorum longus (EDL) muscles in vitro and in vivo using flame photometric determination of Na(+) and K(+) and (36)Cl as a tracer for Cl(-). In vitro, 5-Hz stimulation for 300 s increased intracellular Na(+) content by 4.6 ± 1.2 µmol/g wet wt (P < 0.002) and decreased intracellular K(+) content by 5.5 ± 2.3 µmol/g wet wt (P < 0.03). This would increase [K(+)](o) by 28 ± 12 mM, sufficient to cause severe loss of excitability as the result of inactivation of Na(+) channels. In rat EDL, in vivo stimulation at 5 Hz for 300 s or 60 Hz for 60 s induced significant loss of K(+) (P < 0.01), sufficient to increase [K(+)](o) by 71 ± 22 mM and 73 ± 15 mM, respectively. In spite of this, excitability may be maintained by the rapid and marked stimulation of the electrogenic Na(+),K(+) pumps already documented. This may require full utilization of the transport capacity of Na(+),K(+) pumps, which then becomes a limiting factor for physical performance. In buffer containing (36)Cl, depolarization induced by increasing [K(+)](o) to 40-80 mM augmented intracellular (36)Cl by 120-399% (P < 0.001). Stimulation for 120-300 s at 5-20 Hz increased intracellular (36)Cl by 100-188% (P < 0.001). In rats, Cl(-) transport in vivo was examined by injecting (36)Cl, where electrical stimulation at 5 Hz for 300 s or 60 Hz for 60 s increased (36)Cl uptake by 81% (P < 0.001) and 84% (P < 0.001), respectively, indicating excitation-induced depolarization. Cl(-) influx favors repolarization, improving K(+) clearance and maintenance of excitability. In conclusion, excitation-induced fluxes of Na(+), K(+), and Cl(-) can be quantified in vivo, providing new evidence that in working muscles, extracellular accumulation of K(+) is considerably higher than previously observed and the resulting depression of membrane excitability may be a major cause of muscle fatigue. HubMed – depression

 

Effects of Psycho-Oncologic Interventions on Emotional Distress and Quality of Life in Adult Patients With Cancer: Systematic Review and Meta-Analysis.

Filed under: Depression Treatment

J Clin Oncol. 2013 Jan 14;
Faller H, Schuler M, Richard M, Heckl U, Weis J, Küffner R

PURPOSEThis study aimed to evaluate the effects of psycho-oncologic interventions on emotional distress and quality of life in adult patients with cancer. METHODSLiterature databases were searched to identify randomized controlled trials that compared a psycho-oncologic intervention delivered face-to face with a control condition. The main outcome measures were emotional distress, anxiety, depression, and quality of life. Outcomes were evaluated for three time periods: post-treatment, ? 6 months, and more than 6 months. We applied standard meta-analytic techniques to analyze both published and unpublished data from the retrieved studies. Sensitivity analyses and meta-regression were used to explore reasons for heterogeneity.ResultsWe retrieved 198 studies (covering 22,238 patients) that report 218 treatment-control comparisons. Significant small-to-medium effects were observed for individual and group psychotherapy and psychoeducation. These effects were sustained, in part, in the medium term (? 6 months) and long term (> 6 months). Short-term effects were evident for relaxation training. Studies that preselected participants according to increased distress produced large effects at post-treatment. A moderator effect was found for the moderator variable “duration of the intervention,” with longer interventions producing more sustained effects. Indicators of study quality were often not reported. Small-sample bias indicative of possible publication bias was found for some effects, particularly with individual psychotherapy and relaxation training. CONCLUSIONVarious types of psycho-oncologic interventions are associated with significant, small-to-medium effects on emotional distress and quality of life. These results should be interpreted with caution, however, because of the low quality of reporting in many of the trials.
HubMed – depression

 

More Depression Treatment Information…