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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
171

Label-free multiphoton microscopy reveals relevant tissue changes induced by alginate hydrogel implantation in rat spinal cord injury

Galli, Roberta, Sitoci-Ficici, Kerim H., Uckermann, Ortrud, Later, Robert, Marečková, Magda, Koch, Maria, Leipnitz, Elke, Schackert, Gabriele, Koch, Edmund, Gelinsky, Michael, Steiner, Gerald, Kirsch, Matthias 24 April 2019 (has links)
The development of therapies promoting recovery after spinal cord injury is a challenge. Alginate hydrogels offer the possibility to develop biocompatible implants with mechanical properties tailored to the nervous tissue, which could provide a permissive environment for tissue repair. Here, the effects of non-functionalized soft calcium alginate hydrogel were investigated in a rat model of thoracic spinal cord hemisection and compared to lesioned untreated controls. Open field locomotion tests were employed to evaluate functional recovery. Tissue analysis was performed with label-free multiphoton microscopy using a multimodal approach that combines coherent anti-Stokes Raman scattering to visualize axonal structures, two-photon fluorescence to visualize inflammation, second harmonic generation to visualize collagenous scarring. Treated animals recovered hindlimb function significantly better than controls. Multiphoton microscopy revealed that the implant influenced the injury-induced tissue response, leading to decreased inflammation, reduced scarring with different morphology and increased presence of axons. Demyelination of contralateral white matter near the lesion was prevented. Reduced chronic inflammation and increased amount of axons in the lesion correlated with improved hindlimb functions, being thus relevant for locomotion recovery. In conclusion, non-functionalized hydrogel improved functional outcome after spinal cord injury in rats. Furthermore, label-free multiphoton microscopy qualified as suitable technique for regeneration studies.
172

Exploring the Most Visible German Websites on Melanoma Immunotherapy: A Web-Based Analysis

Brütting, Julia, Steeb, Theresa, Reinhardt, Lydia, Berking, Carola, Meier, Friedegund 25 April 2019 (has links)
Background: Patients diagnosed with melanoma frequently search the internet for treatment information, including novel and complex immunotherapy. However, health literacy is limited among half of the German population, and no assessment of websites on melanoma treatment has been performed so far. Objective: The aim of this study was to identify and assess the most visible websites in German language on melanoma immunotherapy. Methods: In accordance with the common Web-based information-seeking behavior of patients with cancer, the first 20 hits on Google, Yahoo, and Bing were searched for combinations of German synonyms for “melanoma” and “immunotherapy” in July 2017. Websites that met our predefined eligibility criteria were considered for assessment. Three reviewers independently assessed their quality by using the established DISCERN tool and by checking the presence of quality certification. Usability and reliability were evaluated by the LIDA tool and understandability by the Patient Education Materials Assessment Tool (PEMAT). The Flesch Reading Ease Score (FRES) was calculated to estimate the readability. The ALEXA and SISTRIX tools were used to investigate the websites’ popularity and visibility. The interrater agreement was determined by calculating Cronbach alpha. Subgroup differences were identified by t test, U test, or one-way analysis of variance. Results: Of 480 hits, 45 single websites from 30 domains were assessed. Only 2 website domains displayed a German quality certification. The average assessment scores, mean (SD), were as follows: DISCERN, 48 (7.6); LIDA (usability), 40 (2.0); LIDA (reliability), 10 (1.6); PEMAT, 69% (16%); and FRES, 17 (14), indicating mediocre quality, good usability, and understandability but low reliability and an even very low readability of the included individual websites. SISTRIX scores ranged from 0 to 6872 and ALEXA scores ranged from 17 to 192,675, indicating heterogeneity of the visibility and popularity of German website domains providing information on melanoma immunotherapy. Conclusions: Optimization of the most accessible German websites on melanoma immunotherapy is desirable. Especially, simplification of the readability of information and further adaption to reliability criteria are required to support the education of patients with melanoma and laypersons, and to enhance transparency.
173

“Green” Aqueous Synthesis and Advanced Spectral Characterization of Size-Selected Cu2ZnSnS4 Nanocrystal Inks

Stroyuk, Oleksandr, Raevskaya, Alexandra, Selyshchev, Oleksandr, Dzhagan, Volodymyr, Gaponik, Nikolai, Zahn, Dietrich R.T., Eychmüller, Alexander 26 April 2019 (has links)
Structure, composition, and optical properties of colloidal mercaptoacetate-stabilized Cu2ZnSnS4 (CZTS) nanocrystal inks produced by a “green” method directly in aqueous solutions were characterized. A size-selective precipitation procedure using 2-propanol as a non-solvent allows separating a series of fractions of CZTS nanocrystals with an average size (bandgap) varying from 3 nm (1.72 eV) to 2 nm (2.04 eV). The size-selected CZTS nanocrystals revealed also phonon confinement, with the main phonon mode frequency varying by about 4 cm−1 between 2 nm and 3 nm NCs.
174

Clinical, molecular, and immunological responses to pembrolizumab treatment of synchronous melanoma and acute myeloid leukemia

Kubasch, Anne Sophie, Wehner, Rebekka, Bazzurri, Serena, Tunger, Antje, Stasik, Sebastian, Garzarolli, Marlene, Meinel, Jörn, Baretton, Gustavo, Meier, Friedegund, Thiede, Christian, Schmitz, Marc, Platzbecker, Uwe 09 August 2019 (has links)
Cancer cells use the interaction between immune-checkpoint receptor programmed cell death protein 1 (PD-1) on activated T cells and programmed cell death ligand 1 (PD-L1) on tumor cells and various cell types of the tumor microenvironment to evade immune surveillance. Blocking the interaction between PD-1 and PD-L1 with checkpoint inhibitors can improve T-cell reactions and mediate efficient antitumor activity in a variety of solid tumors including melanoma. However, clinical data from patients with myeloid diseases that are treated with these agents are limited to clinical trials in advanced disease. Pembrolizumab (PEM) is a humanized monoclonal antibody of the immunoglobulin G4/κ isotype designed to block PD-1/PD-L1 interactions and is approved for various solid tumors including advanced melanoma.
175

The Higher the Score, the Darker the Core: The Nonlinear Association Between Grandiose and Vulnerable Narcissism

Jauk, Emanuel, Kaufman, Scott Barry 26 September 2018 (has links)
Narcissism is a truly Janusian phenomenon, consisting of both narcissistic grandiosity, exhibitionism, admiration-seeking, boldness, and dominance on the one hand, and narcissistic vulnerability, introversion, withdrawal, hypersensitivity, and anxiety on the other hand. While there is broad consensus that these two seemingly contradictory faces of narcissism can be empirically discerned and have different implications for psychological functioning and mental health, there is not yet agreement on whether grandiose and vulnerable narcissism should be regarded as independent traits or as two manifestations of one personality trait. Previous research indicates that both views hold true when the level of grandiosity is considered a moderating factor: while grandiose and vulnerable narcissism are largely unrelated in the range of normal personality variation, they are correlated in the range of high grandiosity (Jauk et al., 2017b). Here, we replicate and extend this work in an independent sample (N = 891) using a more comprehensive narcissism inventory grounded in a new trifurcated model of narcissism. The trifurcated model partitions narcissism into three main personality dimensions: agentic extraversion, antagonism, and neuroticism. We found a significant breakpoint in the association between narcissistic grandiosity and vulnerability at 75% cumulative frequency of grandiosity. While grandiosity and vulnerability are unrelated below this breakpoint (r = 0.02), they are strongly correlated above (r = 0.45). In the lower range of grandiose narcissism, grandiosity draws more upon agentic extraversion and is largely associated with mental health. In the upper range, however, grandiosity is more strongly linked to antagonism and is substantially associated with fear, negative affect, and depression. These findings provide evidence for the view that grandiose and vulnerable narcissism are distinct traits at lower levels of grandiosity, but blend into an antagonistic core with signs of psychological maladjustment at higher levels. Implications for research on narcissism as a personality trait, as well as clinical practice, are discussed.
176

Impact of customary fuoride rinsing solutions on the pellicle’s protective properties and bioadhesion in situ

Kensche, Anna, Kirsch, Jasmin, Mintert, Sophia, Enders, Franziska, Pötschke, Sandra, Basche, Sabine, König, Belinda, Hannig, Christian, Hannig, Matthias 05 June 2018 (has links) (PDF)
This study investigated the impact of customary fluoride based mouthrinses on the ultrastructure and the functional properties of the in situ pellicle, considering the prevention of erosion (8 volunteers) and initial biofilm formation (12 volunteers). Bovine enamel slabs were carried intraorally. After 1 min of pellicle formation, the subjects rinsed with elmex Kariesschutz (A), Dontodent Med Care (B), meridol (C) or elmex Zahnschmelzschutz Professional (D) for 1 min. In situ pellicle formation was continued up to 30 min/8 h before processing the slabs in vitro. Erosion was simulated by incubating the specimens in HCl (pH 3.0, 2.3, 2.0) for 120 s, measuring the kinetics of calcium/phosphate release photometrically; representative samples were evaluated by TEM and EDX. Bacterial adhesion was visualized fluorescence microscopically (DAPI/BacLight). Native enamel slabs or physiological pellicle samples served as controls. All investigated mouthrinses enhanced the erosion preventive pellicle effect in dependence of the pH-value. A significant decrease of Ca/P release at all pH values was achieved after rinsing with D; TEM/EDX confirmed ultrastructural pellicle modifications. All mouthrinses tendentially reduced bacterial adherence, however not significantly. The mouthrinse containing NaF/AmF/SnCl2 (D) offers an effective oral hygiene supplement to prevent caries and erosion.
177

Luminescence and photoelectrochemical properties of size-selected aqueous copper-doped Ag–In–S quantum dots

Raevskaya, Alexandra, Rozovik, Oksana, Novikova, Anastasiya, Selyshchev, Oleksandr, Stroyuk, Oleksandr, Dzhagan, Volodymyr, Goryacheva, Irina, Gaponik, Nikolai, Zahn, Dietrich R. T., Eychmüller, Alexander 11 June 2018 (has links) (PDF)
Ternary luminescent copper and silver indium sulfide quantum dots (QDs) can be an attractive alternative to cadmium and lead chalcogenide QDs. The optical properties of Cu–In–S and Ag–In–S (AIS) QDs vary over a broad range depending on the QD composition and size. The implementation of ternary QDs as emitters in bio-sensing applications can be boosted by the development of mild and reproducible syntheses directly in aqueous solutions as well as the methods of shifting the photoluminescence (PL) bands of such QDs as far as possible into the near IR spectral range. In the present work, the copper-doping of aqueous non-stoichiometric AIS QDs was found to result in a red shift of the PL band maximum from around 630 nm to ∼780 nm and PL quenching. The deposition of a ZnS shell results in PL intensity recovery with the highest quantum yield of 15%, with almost not change in the PL band position, opposite to the undoped AIS QDs. Size-selective precipitation using 2-propanol as a non-solvent allows discrimination of up to 9 fractions of Cu-doped AIS/ZnS QDs with the average sizes in the fractions varying from around 3 to 2 nm and smaller and with reasonably the same composition irrespective of the QD size. The decrease of the average QD size results in a blue PL shift yielding a series of bright luminophors with the emission color varies from deep-red to bluish-green and the PL efficiency increases from 11% for the first fraction to up to 58% for the smallest Cu-doped AIS/ZnS QDs. The rate constant of the radiative recombination of the size-selected Cu-doped AIS/ZnS QDs revealed a steady growth with the QD size decrease as a result of the size-dependent enhancement of the spatial exciton confinement. The copper doping was found to result in an enhancement of the photoelectrochemical activity of CAIS/ZnS QDs introduced as spectral sensitizers of mesoporous titania photoanodes of liquid-junction solar cells.
178

Fatigue in chronically critically ill patients following intensive care - reliability and validity of the multidimensional fatigue inventory (MFI-20)

Wintermann, Gloria-Beatrice, Rosendahl, Jenny, Weidner, Kerstin, Strauß, Bernhard, Hinz, Andreas, Petrowski, Katja 12 June 2018 (has links) (PDF)
Background Fatigue often occurs as long-term complication in chronically critically ill (CCI) patients after prolonged intensive care treatment. The Multidimensional Fatigue Inventory (MFI-20) has been established as valid instrument to measure fatigue in a wide range of medical illnesses. Regarding the measurement of fatigue in CCI patients, the psychometric properties of the MFI-20 have not been investigated so far. Thus, the present study examines reliability and validity of the MFI-20 in CCI patients. Methods A convenience sample of n = 195 patients with Critical Illness Polyneuropathy (CIP) or Myopathy (CIM) were recruited via personal contact within four weeks (t1) following the transfer from acute care ICU to post-acute ICU at a large rehabilitation hospital. N = 113 (median age 61.1 yrs., 72.6% men) patients were again contacted via telephone three (t2) and six (t3) months following the transfer to post-acute ICU. The MFI-20, the Euro-Quality of Life (EQ-5D-3 L) and the Structured Clinical Interview for the Diagnostic and Statistical Manual of mental disorders DSM-IV (SCID-I) were applied within this prospective cohort study. Results The internal consistency Cronbach’s α was adequate for the MFI-total and all but the subscale Reduced Motivation (RM) (range: .50–.91). Item-to-total correlations (range: .22–.80) indicated item redundancy for the subscale RM. Confirmatory Factor analyses (CFAs) revealed poor model fit for the original 5-factor model of the MFI-20 (t2/t3, Confirmatory Fit Index, CFI = .783/ .834; Tucker-Lewis Index, TLI = .751/ .809; Root Mean Square Error of Approximation, RMSEA = .112/ .103). Among the alternative models (1-, 2-, 3-factor models), the data best fit to a 3-factor solution summarizing the highly correlated factors General −/ Physical Fatigue/ Reduced Activity (GF/ PF/ RA) (t2/ t3, CFI = .878/ .896, TLI = .846/ .869, RMSEA = .089/ .085, 90% Confidence Interval .073–.104/ .066–.104). The MFI-total score significantly correlated with the health-related quality of life (range: −.65-(−).66) and the diagnosis of major depression (range: .27–.37). Conclusions In the present sample of CCI patients, a reliable and valid factor structure of the MFI-20 could not be ascertained. Especially the subscale RM should be revised. Since the factors GF, PF and RA cannot be separated from each other and the unclear factorial structure in the present sample of CCI patients, the MFI-20 is not recommended for use in this context.
179

Bipolar Spectrum Disorders in Male Youth: The Interplay between Symptom Severity, Inflammation, Steroid Secretion, and Body Composition

Walther, Andreas, Penz, Marlene, Ijacic, Daniela, Rice, Timothy R. 04 June 2018 (has links) (PDF)
The morbidity and societal burden of youth bipolar spectrum disorders (BSD) are high. These disorders are multisystemic in that adult populations there are clear interactions with inflammatory processes and steroidal physiological systems. There are much less data concerning these areas of study in youth populations with BSD. This is surprising given the association of youth-onset BSD with puberty and its associated physiological changes. In this mini-review, we overview the theoretical role of inflammatory processes and steroidal physiological systems in youth BSD, describe the greater literature in adult populations, detail the literature in youth populations when available, and overview current proposed molecular mechanistic pathways and interaction effects based on the available data. We also attend to the interplay of this complex system with body composition and weight gain, an especially important consideration in relation to the role of second generation antipsychotics as the first line treatment for youth with BSD in major clinical guidelines. A developmental model of early onset BSD for boys is hypothesized with pubertal hormonal changes increasing risk for first (hypo-)manic/depressive episode. The dramatic androgen rise during puberty might be relevant for first onset of BSD in boys. A shift from general hypercortisolism driven by glucocorticoid resistance to hypocortisolism with further disease progression is assumed, while increased levels of inflammation are functionally associated with endocrine dysregulation. The interacting role of overweight body habitus and obesity in youth with BSD further indicates leptin resistance to be a central moderator of the dynamic neurobiology of BSD in youth. The intent of this mini-review is to advance our knowledge of youth BSD as multisystemic disorders with important contributions from endocrinology and immunology based on a developmental perspective. This knowledge can influence current clinical care and more importantly inform future research.
180

An orthotopic xenograft model for high-risk non-muscle invasive bladder cancer in mice: influence of mouse strain, tumor cell count, dwell time and bladder pretreatment

Hübner, Doreen, Rieger, Christiane, Bergmann, Ralf, Ullrich, Martin, Meister, Sebastian, Toma, Marieta, Wiedemuth, Ralf, Temme, Achim, Novotny, Vladimir, Wirth, Manfred, Bachmann, Michael, Pietzsch, Jens, Fuessel, Susanne 05 June 2018 (has links) (PDF)
Background Novel theranostic options for high-risk non-muscle invasive bladder cancer are urgently needed. This requires a thorough evaluation of experimental approaches in animal models best possibly reflecting human disease before entering clinical studies. Although several bladder cancer xenograft models were used in the literature, the establishment of an orthotopic bladder cancer model in mice remains challenging. Methods Luciferase-transduced UM-UC-3LUCK1 bladder cancer cells were instilled transurethrally via 24G permanent venous catheters into athymic NMRI and BALB/c nude mice as well as into SCID-beige mice. Besides the mouse strain, the pretreatment of the bladder wall (trypsin or poly-L-lysine), tumor cell count (0.5 × 106–5.0 × 106) and tumor cell dwell time in the murine bladder (30 min – 2 h) were varied. Tumors were morphologically and functionally visualized using bioluminescence imaging (BLI), magnetic resonance imaging (MRI), and positron emission tomography (PET). Results Immunodeficiency of the mouse strains was the most important factor influencing cancer cell engraftment, whereas modifying cell count and instillation time allowed fine-tuning of the BLI signal start and duration – both representing the possible treatment period for the evaluation of new therapeutics. Best orthotopic tumor growth was achieved by transurethral instillation of 1.0 × 106 UM-UC-3LUCK1 bladder cancer cells into SCID-beige mice for 2 h after bladder pretreatment with poly-L-lysine. A pilot PET experiment using 68Ga-cetuximab as transurethrally administered radiotracer revealed functional expression of epidermal growth factor receptor as representative molecular characteristic of engrafted cancer cells in the bladder. Conclusions With the optimized protocol in SCID-beige mice an applicable and reliable model of high-risk non-muscle invasive bladder cancer for the development of novel theranostic approaches was established.

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