Lanthanide upconversion luminescence at the nanoscale: fundamentals and optical properties

First published online: 26 Feb 2016Upconversion photoluminescence is a nonlinear effect where multiple lower energy excitation photons produce higher energy emission photons. This fundamentally interesting process has many applications in biomedical imaging, light source and display technology, and solar energy harvesting. In this review we discuss the underlying physical principles and their modelling using rate equations. We discuss how the understanding of photophysical processes enabled a strategic influence over the optical properties of upconversion especially in rationally designed materials. We subsequently present an overview of recent experimental strategies to control and optimize the optical properties of upconversion nanoparticles, focussing on their emission spectral properties and brightness.Annemarie Nadort, Jiangbo Zhao and Ewa M. Goldy

Sensitive cytokine assay based on optical fiber allowing localized and spatially resolved detection of interleukin-6

We demonstrated a cytokine detection device based on gold nanoparticle modified silica optical fiber for the monitoring of locally variable cytokine interleukin-6 (IL-6) concentrations using a sandwich immunoassay scheme. The fiber is designed to be introduced into an intrathecal catheter with micrometer-sized holes drilled along its length to enable fluid exchange between the outside and inside of the catheter. An exposed optical fiber (diameter 125 μm) modified with a layer of gold nanoparticles was functionalized with the IL-6 capture antibody to form the sensing interface. The immunocapture device was incubated with a cytokine solution to capture the analyte. The device was then exposed to the IL-6 detection antibody which was loaded on the fluorescently labeled magnetic nanoparticles, making it possible to quantify the cytokine concentration based on the intensity of fluorescence. A reliable method for quantifying the fluorescent signal on a 3D structure was developed. This device was applied to the detection of cytokine IL-6 with the low limit of detection of 1 pg mL⁻¹ in a sample volume of 1 μL. The device has the linear detection range of 1–400 pg mL⁻¹ and spatial resolution on the order of 200–450 μm, and it is capable of detecting localized IL-6 secreted by live BV2 cells following their liposaccharide stimulation. This biological detection system is suitable for monitoring multiple health conditions.Guozhen Liu, Kaixin Zhang, Annemarie Nadort, Mark R. Hutchinson, and Ewa M. Goldy

Association between lipophilic beta-blockers and depression in diabetic patients on chronic dialysis

BACKGROUND: Depression is associated with lower quality of life and increased risk of mortality. The prevalence of depression in chronic dialysis patients. as well as in patients with diabetes, is more than 20%. It is debated whether use of beta-blockers increases the risk of depression. Therefore. we examined in chronic dialysis patients with and without diabetes. the association between beta-blockers and depressive symptoms.METHODS: Data were collected from the DIVERS-I study. a multicentre prospective cohort among chronic dialysis patients in the Netherlands Depressive symptoms were assessed with the Beck Depression Inventory (BDI-II). We defined depressive symptoms as a BDI-II score >= 16. The cross-sectional association at baseline between depressive symptoms and beta-blocker use in chronic dialysis patients. was studied by multivariable logistic regression adjusted for potential confounders.RESULTS: We included 684 chronic dialysis patients, of whom 43% had diabetes mellitus, and 57% used a beta-blocker of which 97% were lipophilic. After multivariable adjustment, the OR (95% CI) for depressive symptoms in patients with compared to without diabetes was 1.41 (1.00-1.98), and in beta-blocker users compared to non-users 1.12 (0.80-1.56), respectively. Dialysis patients with diabetes and beta-blocker use compared to those without diabetes and not using beta-blockers had an OR of 1.73 (1.12-2.69) for depressive symptoms. The association was stronger in dialysis patients with diabetes and lipophilic beta-blocker use with an OR of 1.77 (1.14-2.74).CONCLUSIONS: We found a possible association between lipophilic beta-blocker use and depressive symptoms in chronic dialysis patients with diabetes.Clinical epidemiolog

Implementation of outpatient schema therapy for borderline personality disorder: study design

ABSTRACT: BACKGROUND: Schema Therapy (ST) is an integrative psychotherapy based upon a cognitive schema model which aims at identifying and changing dysfunctional schemas and modes through cognitive, experiential and behavioral pathways. It is specifically developed for patients with personality disorders. Its effectiveness and efficiency have been demonstrated in a few randomized controlled trials, but ST has not been evaluated in regular mental healthcare settings. This paper describes the study protocol of a multisite randomized 2-group design, aimed at evaluating the implementation of outpatient schema therapy for patients with borderline personality disorder (BPD) in regular mental healthcare and at determining the added value of therapist telephone availability outside office hours in case of crisis. METHODS/DESIGN: Patient outcome measures will be assessed with a semi-structured interview and self-report measures on BPD, therapeutic alliance, quality of life, costs and general psychopathology at baseline, 6, 12, 18 and 36 months. Intention-to-treat analyses will be executed with survival analysis for dichotomous variables, and one-sample t-tests and ANCOVAs for continuous variables with baseline as covariate and condition as between group factor. All tests will be two-tailed with a significance level of 5%. DISCUSSION: The study will provide an answer to the question whether ST can be effectively implemented and whether phone support by the therapist has an additional value. TRIAL REGISTRATION: The Dutch Cochrane Center, NTR (TC = 1781

Design of a multicentered randomized controlled trial on the clinical and cost effectiveness of schema therapy for personality disorders

<p>Abstract</p> <p>Background</p> <p>Despite international guidelines describing psychotherapy as first choice for people with personality disorders (PDs), well-designed research on the effectiveness and cost-effectiveness of psychotherapy for PD is scarce. Schema therapy (ST) is a specific form of psychological treatment that proved to be effective for borderline PD. Randomized controlled studies on the effectiveness of ST for other PDs are lacking. Another not yet tested new specialized treatment is Clarification Oriented Psychotherapy (COP). The aim of this project is to perform an effectiveness study as well as an economic evaluation study (cost effectiveness as well as cost-utility) comparing ST versus COP versus treatment as usual (TAU). In this study, we focus on avoidant, dependent, obsessive-compulsive, paranoid, histrionic and narcissistic PD.</p> <p>Methods/Design</p> <p>In a multicentered randomized controlled trial, ST, and COP as an extra experimental condition, are compared to TAU. Minimal 300 patients are recruited in 12 mental health institutes throughout the Netherlands, and receive an extensive screening prior to enrolment in the study. When eligible, they are randomly assigned to one of the intervention groups. An economic evaluation and a qualitative research study on patient and therapist perspectives on ST are embedded in this trial. Outcome assessments (both for clinical effectiveness and economic evaluation) take place at 6,12,18,24 and 36 months after start of treatment. Primary outcome is recovery from PD; secondary measures include general psychopathological complaints, social functioning and quality of life. Data for the cost-effectiveness and cost-utility analyses are collected by using a retrospective cost interview. Information on patient and therapist perspectives is gathered using in-depth interviews and focus groups, and focuses on possible helpful and impeding aspects of ST.</p> <p>Discussion</p> <p>This trial is the first to compare ST and COP head-to-head with TAU for people with a cluster C, paranoid, histrionic and/or narcissistic PD. By combining clinical effectiveness data with an economic evaluation and with direct information from primary stakeholders, this trial offers a complete and thorough view on ST as a contribution to the improvement of treatment for this PD patient group.</p> <p>Trial registration</p> <p>Netherlands Trial Register (NTR): <a href="http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=566">NTR566</a></p

The (cost) effectiveness of guided internet-based self-help CBT for dialysis patients with symptoms of depression: study protocol of a randomised controlled trial

Background Only a minority of dialysis patients with depressive symptoms are diagnosed and receive treatment. Depressive symptoms are highly prevalent in this population and are associated with adverse clinical outcomes. Underlying factors for this undertreatment may be the lack of evidence for the safety and effectivity of antidepressant medication, the reluctance of patients to adhere to antidepressant medication, the lack of mental healthcare provision in somatic healthcare environments and end-stage renal disease (ESRD) related physical limitations that complicate face-to-face psychotherapy. Guided Internet-based self-help treatment has demonstrated to be effective for depressive symptoms in other chronic patient populations and may overcome these barriers. The aim of this study is to investigate the (cost) effectiveness of a guided Internet-based self-help intervention for symptoms of depression in dialysis patients. Methods This study is a cluster randomized controlled trial (RCT) that investigates the effectiveness of a 5-week Internet-based self-help Problem Solving Therapy (PST) for depressive symptoms in dialysis patients. Depressive symptoms will be measured using the Beck Depression Inventory - second edition (BDI-II), with a cut-off score of >= 10. We aim to include 206 dialysis patients with depressive symptoms who will be cluster randomized to the intervention or the Care as Usual (CAU) control group. Secondary outcomes will include anxiety symptoms, quality of life, economic costs and clinical outcomes, such as inflammatory factors and hair cortisol levels. Assessments will take place at baseline (T0), 2 weeks after intervention (T1) and 6 months (T2), 12 months (T3) and 18 months (T4) after intervention. The control group will be measured at the same time points. Analysis will be based on the intention-to-treat principle. Mixed models will be used to assess the changes within each condition between pre-treatment and post-treatment. Discussion If demonstrated to be (cost) effective, Internet-based PST will offer new possibilities to treat dialysis patients with depressive symptoms and to improve their quality of care.Clinical epidemiolog

General distress and symptoms of anxiety and depression: A factor analysis in two cohorts of dialysis patients

Objective: Depression and anxiety often coexist in patients with end -stage -kidney disease. Recently, studies showed that a composite ?general distress score ? which combines depression and anxiety symptoms provides a good fit in dialysis and oncology patients. We aim to investigate if the three most frequently used self -report questionnaires to measure depression and anxiety in dialysis patients are sufficiently unidimensional to warrant the use of such a general distress score in two cohorts of dialysis patients. Methods: This study includes two prospective observational cohorts of dialysis patients (total n = 749) which measured depression and anxiety using Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI) and Hospital Anxiety and Depression Scale (HADS). Confirmatory factor analyses was used to investigate both a strictly unidimensional model and a multidimensional bifactor model that includes a general distress, depression and anxiety factor. The comparative fit index (CFI) and The Root Mean Square Error of Approximation (RMSEA) were used as model fit indices. Results: Factor analysis did not show a good fit for a strictly unidimensional general distress factor for both the BDI/BAI and HADS (CFI 0.690 and 0.699, RMSEA 0.079 and 0.125 respectively). The multidimensional model performed better with a moderate fit for the BDI/BAI and HADS (CFI 0.873 and 0.839, RMSEA 0.052 and 0.102). Conclusions: This data shows that the BDI/BAI and HADS are insufficiently unidimensional to warrant the use of a general distress score in dialysis patients without also investigating anxiety and depression separately. Future research is needed whether the use of a general distress score might be beneficial to identify patients in need of additional (psychological) support.Clinical epidemiolog