Light Stabilizers

Current trends in the light stabilization of polymers and coatings are summarized, with emphasis on UV absorbers and free-radical scavengers

Ambulatory health services utilization in patients with dementia - Is there an urban-rural difference?

<p>Abstract</p> <p>Background</p> <p>Due to demographic changes and an un-equal distribution of physicians, regional analyses of service utilization of elderly patients are crucial, especially for diseases with an impact like dementia. This paper focuses on dementia patients. The aim of the study is to identify differences in service utilization of incident dementia patients in urban and rural areas.</p> <p>Methods</p> <p>Basis for the analysis were all insured persons of a German Health Insurance fund (the GEK) aged 65 years and older living in rural and urban areas. We focussed on physician contacts in the outpatient sector during the first year after an incidence diagnosis of dementia. Special attention was given to contacts with primary care physicians and neurologists/psychiatrists. The dementia cohort was analyzed together with a non-dementia control group drawn according to age, gender and amount of physician contacts. Uni- and bivariate as well as multivariate analysis were performed to estimate the influences on service utilization.</p> <p>Results</p> <p>Results show that the provision of primary care seems to be equally given in urban and rural areas. For specialists contacts however, rural patients are less likely to consult neurologists or psychiatrists. This trend can already be seen before the incident diagnosis of dementia. All consultations rise in the quarter of the incident dementia diagnosis compared to the control group. The results were also tested in a linear and a logistic regression, showing a higher chance for persons living in urban areas to visit a specialist and an overall higher rate in service utilization for dementia patients.</p> <p>Conclusions</p> <p>Because of a probable increase in the number of dementia patients, service provision has to be accessible even in rural areas. Due to this and the fact that demographic change is happening at different paces in different regions, regional variations have to be considered to ensure the future service provision.</p

Specialist involvement and referral patterns in ambulatory medical care for patients with dementia in Germany: results of a claims data based case-control study.

Background: To analyze the referral processes from general practitioners to specialists and among specialists for dementia patients in the time periods before, during and after the diagnosis in Germany. Methods: In this case-control study claims data from 1,848 insurants with incident dementia aged 65 years and more and 7,392 matched controls were compared over a two-year period covering the pre-incidence, incidence and post-incidence time periods. Results: We found an increase in referrals of 30% in the incidence quarter, mainly from general practice to neuropsychiatry and from there to radiology. Referrals to clinical chemistry and other disciplines for dementia-specific reasons were negligible in amount. 34% of incident cases had at least one contact with a neuropsychiatrist during the year of incidence, and the majority of them visited this specialist repeatedly during that year. Only a minority (13.5%) of patients was referred to radiology for imaging. Referrals to other specialists declined whereas self-referrals did not increase. Conclusions: The referral rates to relevant specialists (neuropsychiatry, radiology and clinical chemistry) are far less frequent than proposed in German guidelines. More research is needed to explain the gape between guidelines and daily care and to find ways for a better implementation of guidelines in ambulatory care. Guidelines should not only deal with diagnostic procedures and therapeutic options but also consider questions of applicability in daily clinical practice and propose effective organizational models of care provision

Poro-viscoelastic material parameter identification of brain tissue-mimicking hydrogels

Understanding and characterizing the mechanical and structural properties of brain tissue is essential for developing and calibrating reliable material models. Based on the Theory of Porous Media, a novel nonlinear poro-viscoelastic computational model was recently proposed to describe the mechanical response of the tissue under different loading conditions. The model contains parameters related to the time-dependent behavior arising from both the viscoelastic relaxation of the solid matrix and its interaction with the fluid phase. This study focuses on the characterization of these parameters through indentation experiments on a tailor-made polyvinyl alcohol-based hydrogel mimicking brain tissue. The material behavior is adjusted to ex vivo porcine brain tissue. An inverse parameter identification scheme using a trust region reflective algorithm is introduced and applied to match experimental data obtained from the indentation with the proposed computational model. By minimizing the error between experimental values and finite element simulation results, the optimal constitutive model parameters of the brain tissue-mimicking hydrogel are extracted. Finally, the model is validated using the derived material parameters in a finite element simulation

Long-term follow-up of IPEX syndrome patients after different therapeutic strategies : an international multicenter retrospective study

Background: Immunodysregulation polyendocrinopathy enteropathy x-linked(IPEX) syndrome is a monogenic autoimmune disease caused by FOXP3 mutations. Because it is a rare disease, the natural history and response to treatments, including allogeneic hematopoietic stem cell transplantation (HSCT) and immunosuppression (IS), have not been thoroughly examined. Objective: This analysis sought to evaluate disease onset, progression, and long-term outcome of the 2 main treatments in long-term IPEX survivors. Methods: Clinical histories of 96 patients with a genetically proven IPEX syndrome were collected from 38 institutions worldwide and retrospectively analyzed. To investigate possible factors suitable to predict the outcome, an organ involvement (OI) scoring system was developed. Results: We confirm neonatal onset with enteropathy, type 1 diabetes, and eczema. In addition, we found less common manifestations in delayed onset patients or during disease evolution. There is no correlation between the site of mutation and the disease course or outcome, and the same genotype can present with variable phenotypes. HSCT patients (n = 58) had a median follow-up of 2.7 years (range, 1 week-15 years). Patients receiving chronic IS (n 5 34) had a median follow-up of 4 years (range, 2 months-25 years). The overall survival after HSCT was 73.2% (95% CI, 59.4-83.0) and after IS was 65.1% (95% CI, 62.8-95.8). The pretreatment OI score was the only significant predictor of overall survival after transplant (P = .035) but not under IS. Conclusions: Patients receiving chronic IS were hampered by disease recurrence or complications, impacting long-term.disease-free survival. When performed in patients with a low OI score, HSCT resulted in disease resolution with better quality of life, independent of age, donor source, or conditioning regimen

The German National Registry of Primary Immunodeficiencies (2012-2017)

Introduction: The German PID-NET registry was founded in 2009, serving as the first national registry of patients with primary immunodeficiencies (PID) in Germany. It is part of the European Society for Immunodeficiencies (ESID) registry. The primary purpose of the registry is to gather data on the epidemiology, diagnostic delay, diagnosis, and treatment of PIDs. Methods: Clinical and laboratory data was collected from 2,453 patients from 36 German PID centres in an online registry. Data was analysed with the software Stata® and Excel. Results: The minimum prevalence of PID in Germany is 2.72 per 100,000 inhabitants. Among patients aged 1–25, there was a clear predominance of males. The median age of living patients ranged between 7 and 40 years, depending on the respective PID. Predominantly antibody disorders were the most prevalent group with 57% of all 2,453 PID patients (including 728 CVID patients). A gene defect was identified in 36% of patients. Familial cases were observed in 21% of patients. The age of onset for presenting symptoms ranged from birth to late adulthood (range 0–88 years). Presenting symptoms comprised infections (74%) and immune dysregulation (22%). Ninety-three patients were diagnosed without prior clinical symptoms. Regarding the general and clinical diagnostic delay, no PID had undergone a slight decrease within the last decade. However, both, SCID and hyper IgE- syndrome showed a substantial improvement in shortening the time between onset of symptoms and genetic diagnosis. Regarding treatment, 49% of all patients received immunoglobulin G (IgG) substitution (70%—subcutaneous; 29%—intravenous; 1%—unknown). Three-hundred patients underwent at least one hematopoietic stem cell transplantation (HSCT). Five patients had gene therapy. Conclusion: The German PID-NET registry is a precious tool for physicians, researchers, the pharmaceutical industry, politicians, and ultimately the patients, for whom the outcomes will eventually lead to a more timely diagnosis and better treatment

Observation of Electron Neutrino Appearance in a Muon Neutrino Beam

The T2K experiment has observed electron neutrino appearance in a muon neutrino beam produced 295 km from the Super-Kamiokande detector with a peak energy of 0.6 GeV. A total of 28 electron neutrino events were detected with an energy distribution consistent with an appearance signal, corresponding to a significance of 7.3σ when compared to 4.92 ± 0.55 expected background events. In the PMNS mixing model, the electron neutrino appearance signal depends on several parameters including three mixing angles θ12, θ23, θ13, a mass difference Δm232 and a CP violating phase δCP. In this neutrino oscillation scenario, assuming |Δm232|=2.4×10−3 eV2, sin2θ23=0.5, δCP=0, and Δm232>0 (Δm232<0), a best-fit value of sin22θ13 = 0.140+0.038−0.032 (0.170+0.045−0.037) is obtained