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Eu3+-doped barium borate glasses are analysed for their optical and excitation power dependent luminescence properties. The glasses, doped with different concentrations of the lanthanide ion Eu3+, provide photoluminescence quantum efficiencies higher than 80% and, show a bright luminescence in the red spectral range, making them attractive for lighting applications. [ABSTRACT FROM AUTHOR]

The ratio between the network modifier Li2O and the network former B2O3 has a significant influence on the structural and optical properties of Dy3+-doped lithium borate glass. Differential scanning calorimetry shows that upon increasing the modifier-to-former ratio (Li2O-to-B2O3) in favour of Li2O, the glass transition temperature increases up to a maximum value of 502°C for the 1:3 sample, while the crystallization temperature decreases linearly from 653 to 534°C. Raman spectroscopy confirms the highest network connectivity for the glass with a modifier-to-former ratio of 1:3. Under ultraviolet excitation, Dy3+ shows emission lines in the visible spectral range, the most intense ones at 484 and 575 nm. The absolute photoluminescence quantum efficiency is best for the glass with a modifier-to-former ratio of 1:6. [ABSTRACT FROM AUTHOR]

Tb3+ and Eu3+ single-doped barium borate glass and ZBLAN glass are investigated for their photoluminescence (PL) and absolute PL quantum efficiency. In addition, both glass systems are characterized with respect to their color stability in the temperature range from 25 °C to 400 °C. The Tb3+ doped glass shows high color stability over the entire temperature range investigated, whereas the Eu3+ doped glass changes its color appearance with increasing temperature: Eu3+ in ZBLAN glass changes its color appearance from the orange to the red spectral range, whereas the color appearance in borate glass is shifted from the red to the orange-red spectral range. (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Objective. Patients with both major depression and personality disorders have a high risk of suicidal behavior. Lithium is meant to have anti-suicidal properties in patients with affective disorders. The anti-suicidal effect of lithium in patients with affective disorders and comorbid personality disorders has not been investigated yet. Methods. A post-hoc analysis of a subsample of patients with depression and comorbid personality disorder (PD) and a recent suicide attempt ( n = 19) from the prospective, placebo-controlled lithium intervention study ( N = 167), was conducted. Results. Three patients in the lithium group ( n = 8) and two patients in the placebo group ( n = 11) presented a suicide attempt throughout the course of the study. No differences related to suicidal behavior could be detected between the placebo group and the group with lithium intervention. Conclusions. On the basis of the small sample size, among patients with comorbid PD, lithium does not seem to have an effect on suicidal behavior in contrast to patients with affective disorders without comorbid PD. [ABSTRACT FROM AUTHOR]

The article reviews the existing evidence and the concept of the anti-suicidal effect of lithium long-term treatment in bipolar patients. The core studies supporting the concept of a suicide preventive effect of lithium in bipolar patients come from the international research group IGSLI, from Sweden, Italy, and recently also from the U.S. Patients on lithium possess an eight- time lower suicide risk than those off lithium. The anti-suicidal effect is not necessarily coupled to lithium's episode suppressing efficacy. The great number of lives potentially saved by lithium adds to the remarkable benefits of lithium in economical terms. The evidence that lithium can effectively reduce suicide risk has been integrated into modern algorithms in order to select the optimal maintenance therapy for an individual patient. [ABSTRACT FROM AUTHOR]

Several studies have shown that there is a significantly increased risk of suicide related mortality in patients with a positive history of suicide attempts. The SUPLI-Study is the first prospective, randomized, double blind, placebo controlled multi-center trial focusing on the proposed suicide preventive effects of lithium in patients with suicidal behavior but not suffering from bipolar disorder or recurrent major depressive disorder. Patients with a recent history of a suicide attempt are treated with lithium versus placebo during a 12 month period. The hypothesis is that lithium treatment will lead to a 50% reduction of suicidal behavior. The protocol of the study and preliminary results are presented. [ABSTRACT FROM AUTHOR]

The suicide-related mortality among patients with affective disorders is approximately 30 times higher, and overall mortality 2 to 3 times higher, than suicide-related mortality in the general population. Lithium has demonstrated possibly specific antisuicidal effects apart from its prophylactic efficacy: it significantly reduces the high excess mortality of patients with affective disorders. To date, suicide-prevention effects have not been shown for antidepressant or anticonvulsant long-term treatment. Clozapine appears to reduce the suicide rate in schizophrenia patients. Against this background, guidelines and algorithms for selecting an appropriate prophylactic strategy for affective disorders should consider the presence of suicidality in patient history. Appropriate lithium prophylaxis prevents approximately 250 suicides yearly in Germany, although lithium salts are infrequently prescribed within the National Health Scheme (specifically, to 0.06% of the population). Rational treatment strategies most likely would demand that prescription rates be about 10 times higher. [ABSTRACT FROM AUTHOR]

Objective: A model for the development of anxiety disorders (panic disorder with or without agoraphobia) is needed. Patients with an implantable cardioverter/defibrillator (ICD) are exposed to repeated electric shocks. If the theory of anxiety development by aversive classic conditioning processes is valid, these repeated shocks should lead to an increased risk of anxiety disorders. To study this hypothesis, we retrospectively studied 72 patients after implantation of an automatic ICD.Methods: Patients were assessed with the semistructured Diagnostic Interview of Psychiatric Disease 1 to 6 years after implantation of an automatic ICD. Panic disorder and/or agoraphobia was diagnosed in patients who fulfilled all DSM-III-R criteria for those conditions.Results: Anxiety disorder developed in 15.9% of patients after ICD implantation. This was significantly related to the frequency of repeated defibrillation (shocks) to stop malignant ventricular arrhythmias. Dysfunctional cognitions are an additional vulnerability factor.Conclusions: The data support both the conditioning hypothesis and the cognitive model of anxiety development. These findings suggest that ICD patients are an appropriate risk population for a prospective study of the development of anxiety disorders. [ABSTRACT FROM AUTHOR]

We found enhanced upconverted fluorescence in Nd3+-doped fluorozirconate glasses which were additionally doped with chlorine ions. Upon annealing between 240 and 290°C, hexagonal phase BaCl2 nanocrystals between 20 and 180 nm in diameter were formed in the glass. During the thermal processing, some of the Nd3+ ions enter the nanocrystals leading to additional splitting of the infrared fluorescence spectra and to increased upconverted fluorescence intensities. The optimum value was found for the 270°C sample where the upconverted fluorescence intensity is approximately a factor of 60 stronger than the one found for the as-made glass. [ABSTRACT FROM AUTHOR]

New multifunctional nanoparticles (NPs) that can be used as contrast agents (CA) in different imaging techniques, such as photoluminescence (PL) microscopy and magnetic resonance imaging (MRI), open new possibilities for medical imaging, e.g., in the fields of diagnostics or tissue characterization in regenerative medicine. The focus of this study is on the synthesis and characterization of CaF 2 :(Tb 3+ ,Gd 3+ ) NPs. Fabricated in a wet-chemical procedure, the spherical NPs with a diameter of 5-10 nm show a crystalline structure. Simultaneous doping of the NPs with different lanthanide ions, leading to paramagnetism and fluorescence, makes them suitable for MR and PL imaging. Owing to the Gd 3+ ions on the surface, the NPs reduce the MR T 1 relaxation time constant as a function of their concentration. Thus, the NPs can be used as a MRI CA with a mean relaxivity of about r = 0.471 mL·mg -1 ·s -1 . Repeated MRI examinations of four different batches prove the reproducibility of the NP synthesis and determine the long-term stability of the CAs. No cytotoxicity of NP concentrations between 0.5 and 1 mg·mL -1 was observed after exposure to human dermal fibroblasts over 24 h. Overall this study shows, that the CaF 2 :(Tb 3+ ,Gd 3+ ) NPs are suitable for medical imaging.