509 research outputs found

    Entwicklung eines Sandwich Enzyme-linked Immunosorbent Assays zum Nachweis von humanem α-Synuclein

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    Die Zunahme von neurodegenerativen Erkrankungen bedeutet nicht nur aus medizinischer, sondern auch aus sozialer und gesundheitspolitischer Sicht eine besondere Herausforderung für unsere Gesellschaft (Eller und Williams 2011). Die Prävalenz von PD nimmt innerhalb von 30 Jahren von 0,6% in der Altersgruppe der 65- bis 69-Jährigen auf 3,5% bei den über 85-Jährigen zu (de Rijk et al. 1997). Aufgrund der demografischen Entwicklung ist in den kommenden Jahren ein weiterer Anstieg der Patientenzahlen zu erwarten. Bisher gibt es noch keinen zuverlässigen, laborchemischen Biomarker, der eine Frühdiagnose von Synucleinopathien oder eine Aussage über den Verlauf der Erkrankung ermöglicht (Eller und Williams 2009). Bereits veröffentlichte Studien weisen auf einen Zusammenhang zwischen dem Vorliegen einer Synucleinopathie und der α-Synucleinkonzentration im Blut hin. Jedoch ergaben die Untersuchungen widersprüchliche Ergebnisse bezüglich einer möglichen Korrelation und der Höhe der α-Synucleinkonzentration. Ziel dieser Arbeit war es, einen sensitiven und spezifischen Sandwich-ELISA zum Nachweis humanen α-Synucleins in Standards und Plasmaproben zu entwickeln. Für die Durchführung des ELISA mussten geeignete mono- und polyklonale Antikörper, Beschichtungs- und Verdünnungspuffer, Blockierlösungen und das optimale Amplifizierungs- und Nachweissystem gewählt werden. Zwar konnte eine ausreichende Sensitivität, jedoch keine hinreichende Genauigkeit des ELISA für den quantitativen Nachweis von α-Synuclein im Plasma erzielt werden. Im nächsten Schritt wurden 95 Plasmaproben eines Normalkollektivs und jeweils 10 Plasmaproben von Patienten mit AD, DLB und einer gesunden Kontrollgruppe getestet. Dabei lag der Fokus auf möglichen Unterschieden zwischen der α-Synucleinkonzentration beim Normal- und Patientenkollektiv und dem Alter der Probanden. Die α-Synucleinkonzentration wurde mit Hilfe des entwickelten ELISA bestimmt. Das Ergebnis der vorliegenden Studie zeigte keinen signifikanten Unterschied zwischen der α-Synucleinkonzentration bei Patienten mit AD, DLB und der gesunden Kontrollgruppe. Zudem konnte kein Zusammenhang zwischen der α-Synucleinkonzentration und dem Alter der Patienten festgestellt werden. Zusammenfassend könnte α-Synuclein ein potenzieller Biomarker sein, der sich als Indikator für spezifische pathophysiologische Prozesse der Synucleinopathien eignet (Stefanis 2012). Dabei erscheint die liquorbasierte Diagnostik von α-Synuclein als vielversprechend, da Studienergebnisse eine höhere Übereinstimmung bei der Untersuchung von Liquor als von Blut ergaben (Kasuga und Ikeuchi 2012). Jedoch sind bisherige Ergebnisse nicht ausreichend präzise und verlässlich genug, um α-Synuclein als Biomarker im klinischen Alltag zur Sicherung von Diagnosen einzusetzen (Eller und Williams 2011)

    Alternative respiratory chain enzymes: Therapeutic potential and possible pitfalls

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    The alternative respiratory chain (aRC), comprising the alternative NADH dehydrogenases (NDX) and quinone oxidases (AOX), is found in microbes, fungi and plants, where it buffers stresses arising from restrictions on electron flow in the oxidative phosphorylation system. The aRC enzymes are also found in species belonging to most metazoan phyla, including some chordates and arthropods species, although not in vertebrates or in Drosophila. We postulated that the aRC enzymes might be deployed to alleviate pathological stresses arising from mitochondrial dysfunction in a wide variety of disease states. However, before such therapies can be contemplated, it is essential to understand the effects of aRC enzymes on cell metabolism and organismal physiology. Here we report and discuss new findings that shed light on the functions of the aRC enzymes in animals, and the unexpected benefits and detriments that they confer on model organisms. In Ciona intestinalis, the aRC is induced by hypoxia and by sulfide, but is unresponsive to other environmental stressors. When expressed in Drosophila, AOX results in impaired survival under restricted nutrition, in addition to the previously reported male reproductive anomalies. In contrast, it confers cold resistance to developing and adult flies, and counteracts cell signaling defects that underlie developmental dysmorphologies. The aRC enzymes may also influence lifespan and stress resistance more generally, by eliciting or interfering with hormetic mechanisms. In sum, their judicious use may lead to major benefits in medicine, but this will require a thorough characterization of their properties and physiological effects.Peer reviewe

    Low levels of IgM antibodies recognizing oxidation-specific epitopes are associated with human non-alcoholic fatty liver disease

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    Background: Lipid oxidation of membrane phospholipids is accompanied by the formation of oxidation-specific epitopes (OSE). These epitopes are recognized by specific antibodies and represent danger-associated molecular patterns that are generated during chronic inflammatory processes. In a murine model for hepatic inflammation during non-alcoholic fatty liver disease (NAFLD), increased antibody levels targeting OSE were found to be protective. Here, our aim was to determine an association between OSE-specific antibody titers and NAFLD in humans. Methods: IgM and IgG levels with specificity for various OSE were assessed in the plasma of patients with NAFLD (n = 71) and healthy controls (n = 68). Antibody titers were comprehensively analyzed in patients with NAFLD after classification by histological evaluation of liver biopsies. Statistical analysis was performed to determine significant correlations and odds ratios. To study the specificity for NAFLD, plasma antibody titers were measured in patients with hepatitis C (n = 40) and inflammatory bowel disease (n = 62). Results: IgM titers against OSE were lower in patients with NAFLD compared to controls. Further biopsy-based classification of patients with NAFLD did not show any difference in IgM levels. Plasma IgM titers towards the P1 mimotope demonstrated an inverse correlation with markers for obesity, systemic inflammation, and liver damage. In contrast, hepatitis C and increased disease activity during inflammatory bowel disease was not associated with reduced IgM titers. Conclusions: Our data highlight the importance of immune recognition of OSE by IgM antibodies in the pathophysiology of NAFLD

    A Case for Humans-in-the-Loop: Decisions in the Presence of Erroneous Algorithmic Scores

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    The increased use of algorithmic predictions in sensitive domains has been accompanied by both enthusiasm and concern. To understand the opportunities and risks of these technologies, it is key to study how experts alter their decisions when using such tools. In this paper, we study the adoption of an algorithmic tool used to assist child maltreatment hotline screening decisions. We focus on the question: Are humans capable of identifying cases in which the machine is wrong, and of overriding those recommendations? We first show that humans do alter their behavior when the tool is deployed. Then, we show that humans are less likely to adhere to the machine's recommendation when the score displayed is an incorrect estimate of risk, even when overriding the recommendation requires supervisory approval. These results highlight the risks of full automation and the importance of designing decision pipelines that provide humans with autonomy.Comment: Accepted at ACM Conference on Human Factors in Computing Systems (ACM CHI), 202

    Zum Leistungs- und Entwicklungsstand inklusiv beschulter Schülerinnen und Schüler mit (sonder-)pädagogischen Förderbedarfen auf der Insel Rügen nach fünf Schulbesuchsjahren

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    Der hier vorgelegte Forschungsbericht dient im Wesentlichen der Evaluation der Arbeit der Regionalen Schulen auf Rügen mit Schülerinnen und Schülern mit einem (sonder-)pädagogischen Förderbedarf in den Bereichen Lernen, emotional-soziale Entwicklung und Sprache am Ende des Schuljahres 2014/15, und damit der ersten Versuche des Umgangs mit den neuen Herausforderungen im Kontext von Inklusion. Zudem wird in einer vorangestellten ersten Teilstudie der Leistungsstand von Schülerinnen und Schülern am Ende ihrer Grundschulzeit betrachtet, die innerhalb der Grundschule ein Schuljahr wiederholten bzw. zeitweise eine Diagnoseförderklasse (DFK) besuchten. Der Bericht gliedert sich dementsprechend in zwei Teilstudien, deren Ergebnisse abschließend gemeinsam betrachtet und interpretiert werden

    Non-specific interstitial pneumonia in cigarette smokers: a CT study

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    The goal of this study was to seek indirect evidence that smoking is an aetiological factor in some patients with non-specific interstitial pneumonia (NSIP). Ten current and eight ex-smokers with NSIP were compared to controls including 137 current smokers with no known interstitial lung disease and 11 non-smokers with NSIP. Prevalence and extent of emphysema in 18 smokers with NSIP were compared with subjects meeting GOLD criteria for chronic obstructive pulmonary disease (COPD; group A; n = 34) and healthy smokers (normal FEV1; group B; n = 103), respectively. Emphysema was present in 14/18 (77.8%) smokers with NSIP. Emphysema did not differ in prevalence between NSIP patients and group A controls (25/34, 73.5%), but was strikingly more prevalent in NSIP patients than in group B controls (18/103, 17.5%, P < 0.0005). On multiple logistic regression, the likelihood of emphysema increased when NSIP was present (OR = 18.8; 95% CI = 5.3–66.3; P < 0.0005) and with increasing age (OR = 1.04; 95% CI = 0.99–1.11; P = 0.08). Emphysema is as prevalent in smokers with NSIP as in smokers with COPD, and is strikingly more prevalent in these two groups than in healthy smoking controls. The association between NSIP and emphysema provides indirect support for a smoking pathogenesis hypothesis in some NSIP patients

    Alternative respiratory chain enzymes: Therapeutic potential and possible pitfalls

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    The alternative respiratory chain (aRC), comprising the alternative NADH dehydrogenases (NDX) and quinone oxidases (AOX), is found in microbes, fungi and plants, where it buffers stresses arising from restrictions on electron flow in the oxidative phosphorylation system. The aRC enzymes are also found in species belonging to most metazoan phyla, including some chordates and arthropods species, although not in vertebrates or in Drosophila. We postulated that the aRC enzymes might be deployed to alleviate pathological stresses arising from mitochondrial dysfunction in a wide variety of disease states. However, before such therapies can be contemplated, it is essential to understand the effects of aRC enzymes on cell metabolism and organismal physiology. Here we report and discuss new findings that shed light on the functions of the aRC enzymes in animals, and the unexpected benefits and detriments that they confer on model organisms. In Ciona intestinalis, the aRC is induced by hypoxia and by sulfide, but is unresponsive to other environmental stressors. When expressed in Drosophila, AOX results in impaired survival under restricted nutrition, in addition to the previously reported male reproductive anomalies. In contrast, it confers cold resistance to developing and adult flies, and counteracts cell signaling defects that underlie developmental dysmorphologies. The aRC enzymes may also influence lifespan and stress resistance more generally, by eliciting or interfering with hormetic mechanisms. In sum, their judicious use may lead to major benefits in medicine, but this will require a thorough characterization of their properties and physiological effects.</p

    Influence of Interferon-Alpha Combined with Chemo (Radio) Therapy on Immunological Parameters in Pancreatic Adenocarcinoma

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    Prognosis of patients with carcinoma of the exocrine pancreas is particularly poor. A combination of chemotherapy with immunotherapy could be an option for treatment of pancreatic cancer. The aim of this study was to perform an immunomonitoring of 17 patients with pancreatic cancer from the CapRI-2 study, and tumor-bearing mice treated with combination of chemo (radio) therapies with interferon-2. Low doses of interferon-2 led to a decrease in total leukocyte and an increase in monocyte counts. Furthermore, we observed a positive effect of interferon-2 therapy on the dendritic cells and NK (natural killer) cell activation immediately after the first injection. In addition, we recorded an increased amount of interferon- and IL-10 in the serum following the interferon-2 therapy. These data clearly demonstrate that pancreatic carcinoma patients also show an immunomodulatory response to interferon-2 therapy. Analysis of immunosuppressive cells in the Panc02 orthotopic mouse model of pancreatic cancer revealed an accumulation of the myeloid-derived suppressor cells in spleens and tumors of the mice treated with interferon-2 and 5-fluorouracil. The direct effect of the drugs on myeloid-derived suppressor cells was also registered in vitro. These data expose the importance of immunosuppressive mechanisms induced by combined chemo-immunotherapy

    Lung diffusing capacity for nitric oxide and carbon monoxide in relation to morphological changes as assessed by computed tomography in patients with cystic fibrosis

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    Background Due to large-scale destruction, changes in membrane diffusion (Dm) may occur in cystic fibrosis (CF), in correspondence to alterations observed by computed tomography (CT). Dm can be easily quantified via the diffusing capacity for nitric oxide (DLNO), as opposed to the conventional diffusing capacity for carbon monoxide (DLCO). We thus studied the relationship between DLNO as well as DLCO and a CF-specific CT score in patients with stable CF. Methods Simultaneous single-breath determinations of DLNO and DLCO were performed in 21 CF patients (mean ± SD age 35 ± 9 y, FEV1 66 ± 28%pred). Patients also underwent spirometry and bodyplethysmography. CT scans were evaluated via the Brody score and rank correlations (rS) with z-scores of functional measures were computed. Results CT scores correlated best with DLNO (rS = -0.83; p < 0.001). Scores were also related to the volume-specific NO transfer coefficient (KNO; rS = -0.63; p < 0.01) and to DLCO (rS = -0.79; p < 0.001) but not KCO. Z-scores for DLNO were significantly lower than for DLCO (p < 0.001). Correlations with spirometric (e.g., FEV1, IVC) or bodyplethysmographic (e.g., SRaw, RV/TLC) indices were weaker than for DLNO or DLCO but most of them were also significant (p < 0.05 each). Conclusion In this cross sectional study in patients with CF, DLNO and DLCO reflected CT-morphological alterations of the lung better than other measures. Thus the combined diffusing capacity for NO and CO may play a future role for the non-invasive, functional assessment of structural alterations of the lung in CF

    Motor, cognitive and mobility deficits in 1000 geriatric patients : protocol of a quantitative observational study before and after routine clinical geriatric treatment – the ComOn-study

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    © The Author(s). 2020 Open Access. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Background: Motor and cognitive deficits and consequently mobility problems are common in geriatric patients. The currently available methods for diagnosis and for the evaluation of treatment in this vulnerable cohort are limited. The aims of the ComOn (COgnitive and Motor interactions in the Older populatioN) study are (i) to define quantitative markers with clinical relevance for motor and cognitive deficits, (ii) to investigate the interaction between both motor and cognitive deficits and (iii) to assess health status as well as treatment outcome of 1000 geriatric inpatients in hospitals of Kiel (Germany), Brescia (Italy), Porto (Portugal), Curitiba (Brazil) and Bochum (Germany). Methods: This is a prospective, explorative observational multi-center study. In addition to the comprehensive geriatric assessment, quantitative measures of reduced mobility and motor and cognitive deficits are performed before and after a two week's inpatient stay. Components of the assessment are mobile technology-based assessments of gait, balance and transfer performance, neuropsychological tests, frailty, sarcopenia, autonomic dysfunction and sensation, and questionnaires to assess behavioral deficits, activities of daily living, quality of life, fear of falling and dysphagia. Structural MRI and an unsupervised 24/7 home assessment of mobility are performed in a subgroup of participants. The study will also investigate the minimal clinically relevant change of the investigated parameters. Discussion: This study will help form a better understanding of symptoms and their complex interactions and treatment effects in a large geriatric cohort.info:eu-repo/semantics/publishedVersio
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