906 resultados para setting of operating target
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Das vorliegende Werk behandelt die Ursachen für die Nicht-, Schwer- und Missverständlichkeit von Bedienungsanleitungen und Instruktionen sowohl theoretisch durch eine Auswertung der einschlägigen Fachliteratur als auch praktisch durch eine empirische Untersuchung dreier Informationsprodukte. Zur Veranschaulichung der Tragweite von dysfunktionalen Instruktionen stellt die vorliegende Arbeit zunächst die rechtlichen Rahmenbedingungen für Bedienungsanleitungen dar. Im Anschluss daran erläutert sie die thematisch relevanten Kommunikationstheorien, die grundlegenden Kommunikationsmodelle sowie die zentralen Theorien der Kognitionswissenschaft zur Textverarbeitung und zum Textverstehen als Grundlage für die durchgeführten Lese- und Benutzertests. Die praktische Untersuchung veranschaulicht die vielfältigen und omnipräsenten Ursachen für eine dysfunktionale Rezeption von Instruktionen und legt aufgrund der potenziell gefährlichen Folgen die Durchführung von Benutzertests zur retrospektiven Vermeidung von Kommunikationsstörungen und zur prospektiven Stärkung des Problembewusstseins bei der Erstellung von Bedienungsanleitungen nahe.
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Solid organ transplantation (SOT) is considered the treatment of choice for many end-stage organ diseases. Thus far, short term results are excellent, with patient survival rates greater than 90% one year post-surgery, but there are several problems with the long term acceptance and use of immunosuppressive drugs. Hematopoietic Stem Cells Transplantation (HSCT) concerns the infusion of haematopoietic stem cells to re-establish acquired and congenital disorders of the hematopoietic system. The main side effect is the Graft versus Host Disease (GvHD) where donor T cells can cause pathology involving the damage of host tissues. Patients undergoing acute or chronic GvHD receive immunosuppressive regimen that is responsible for several side effects. The use of immunosuppressive drugs in the setting of SOT and GvHD has markedly reduced the incidence of acute rejection and the tissue damage in GvHD however, the numerous adverse side effects observed boost the development of alternative strategies to improve the long-term outcome. To this effect, the use of CD4+CD25+FOXP3+ regulatory T cells (Treg) as a cellular therapy is an attractive approach for autoimmunity disease, GvHD and limiting immune responses to allograft after transplantation. Treg have a pivotal role in maintaining peripheral immunological tolerance, by preventing autoimmunity and chronic inflammation. Results of my thesis provide the characterization and cell processing of Tregs from healthy controls and patients in waiting list for liver transplantation, followed by the development of an efficient expansion-protocol and the investigation of the impact of the main immunosuppressive drugs on viability, proliferative capacity and function of expanded cells after expansion. The conclusion is that ex vivo expansion is necessary to infuse a high Treg dose and although many other factors in vivo can contribute to the success of Treg therapy, the infusion of Tregs during the administration of the highest dose of immunosuppressants should be carefully considered.
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The general aim of this dissertation was to uncover the association between psychosocial factors and rehabilitation outcome after stroke. METHOD. A sample of patients with stroke (n=40) and their caregivers (n=36) were assessed at admission to and six months after discharge from rehabilitation hospital, using the following instruments: Structured Clinical Interview for DSM-IV, structured interview based on Diagnostic Criteria for Psychosomatic Research, Symptom Questionnaire, Psychosocial Index, Psychological Well-Being Scales, and Family Assessment Device. 40 subjects from the general population underwent the same psychological assessment. In addition, patients' functional status was measured using the Functional Independence Measure. RESULTS. Stroke survivors reported lower education and higher alcohol consumption than controls. No significant differences emerged between the two groups in the prevalence of psychiatric diagnoses or psychosomatic syndromes, however patients reported significantly higher levels of anxiety, depression, somatic symptoms, and lower autonomy than controls. Caregivers reported significantly higher scores in anxiety, depression, and somatic symptoms compared to normative data, while no impairments emerged in psychological well-being and family functioning. At six-month follow-up, in patients a significant decrease in smoking habit and an increase in DSM diagnoses were reported. Both stroke survivors and caregivers showed significant reductions in anxiety, with patients displaying also a decrease in somatic symptoms, an increase in stress and a deterioration in quality of life. Significant deteriorations in several aspects of family functioning was perceived only by patients. An association between patients' functional recovery in the cognitive domain and family behavior control emerged. For caregivers, family functioning significantly predicted hostility and somatic symptoms were associated with family affective involvement. CONCLUSIONS. These data highlight the utility in the Italian setting of the adoption of a psychosocial assessment and a family-systems approach in stroke rehabilitation, in order to development interventions properly targeted to the characteristics of patients and their family members.
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The interest of the scientific community towards organic pollutants in freshwater streams is fairly recent. During the past 50 years, thousands of chemicals have been synthesized and released into the general environment. Nowadays their occurrence and effects on several organism, invertebrates, fish, birds, reptiles and also humans are well documented. Because of their action, some of these chemicals have been defined as Endocrine Disrupters Compounds (EDCs) and the public health implications of these EDCs have been the subject of scientific debate. Most interestingly, among those that were noticed to have some influence and effects on the endocrine system were the estrone, the 17β-estradiol, the 17α-estradiol, the estriol, the 17α-ethinylestradiol, the testosterone and the progesterone. This project focused its attention on the 17β-estradiol. Estradiol, or more precisely, 17β-estradiol (also commonly referred to as E2) is a human sex hormone. It belongs to the class of steroid hormones. In spite of the effort to remove these substances from the effluents, the actual wastewater treatment plants are not able to degrade or inactivate these organic compounds that are continually poured in the ecosystem. Through this work a new system for the wastewater treatment was tested, to assess the decrease of the estradiol in the water. It involved the action of Chlorella vulgaris, a fresh water green microalga belonging to the family of the Chlorellaceae. This microorganism was selected for its adaptability and for its photosynthetic efficiency. To detect the decrease of the target compound in the water a CALUX bioassay analysis was chosen. Three different experiments were carried on to pursue the aim of the project. By analysing their results several aspects emerged. It was assessed the presence of EDCs inside the water used to prepare the culture media. C. vulgaris, under controlled conditions, could be efficient for this purpose, although further researches are essential to deepen the knowledge of this complex phenomenon. Ultimately by assessing the toxicity of the effluent against C. vulgaris, it was clear that at determined concentrations, it could affect the normal growth rate of this microorganism.
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Dendritische Zellen (DC) spielen als professionelle antigenpräsentierende Zellen (APC) eine zentrale Rolle in der Aktivierung und Regulierung antigenspezifischer Immunantworten. Aus diesem Grund wird der therapeutische Einsatz von DC zur Behandlung von Autoimmunerkrankungen und Allergien sowie zur Tumorbekämpfung erforscht. Im ersten Teil der vorliegenden Arbeit untersuchten wir das Potenzial einer biolistischen DNA-Vakzinierung zur Induktion tolerogener DC in vivo. Im Tiermodell der Myelin-Oligodendrozyten-Glykoprotein Peptid 35-55 (MOGp35-55) induzierten experimentellen autoimmunen Enzephalomyelitis (EAE) sollte mittels präventiver biolistischer Kovakzinierung von Plasmid-DNA kodierend für MOG und die immunregulatorischen Zytokine TGFβ oder IL-10 eine protektive Immunität induziert werden. Die MOG-Expression stand dabei entweder unter der Kontrolle des ubiquitär aktiven CMV-Promotors oder des murinen Fascin-Promotors, um eine ektopische MOG-Expression spezifisch in dermalen DC und Langerhanszellen zu erreichen. Dass MOGp35-55-präsentierende DC nach biolistischer DNA-Vakzinierung von der Haut in die drainierenden Lymphknoten migrieren und dort T-Zellen aktivieren, konnte im Vorfeld anhand einer substanziellen Proliferation von MOGp35-55-reaktiven 2D2 T-Zellen nachgewiesen werden. Im präventiven Ansatz der MOGp35-55-induzierten EAE zeigten Mäuse, die mit MOG-kodierenden Plasmiden biolistisch transfiziert wurden, eine leicht reduzierte EAE-Symptomatik. Die Kotransfektion von MOG und TGFβ führte zu einer Verstärkung der EAE-Suppression – unabhängig davon, ob die MOG-Expression unter der Kontrolle des CMV- oder des Fascin-Promotors stand. Interessanterweise resultierte die Koapplikation von MOG- und IL-10-kodierender Plasmid-DNA nur bei DC-fokussierter MOG-Expression zu reduzierter EAE-Symptomatik. Für biolistische DNA-Vakzinierungen stellt somit der Fascin-Promotor eine potente Alternative zu viralen Promotoren dar. Entsprechend der milderen EAE-Symptome beobachteten wir bei behandelten EAE-Mäusen einen geringeren Grad an Demyelinisierung sowie eine reduzierte Infiltration des ZNS mit IFNγ-produzierenden CD4+ Th1- und IL-17-produzierenden CD4+ Th17-Zellen. Desweiteren zeigten Milzzellen ex vivo nach MOGp35-55-Restimulation eine inhibierte Proliferation und eine signifikant reduzierte IFNγ- und IL-17-Zytokinproduktion. Überraschenderweise ging die antigenspezifische Immunsuppression nicht mit der Expansion von Foxp3+ regulatorischen T-Zellen einher. Da die Milzen aber erhöhte Mengen an CD8+IFNγ+ T-Zellen aufweisen, könnte ein zytotoxisch-suppressiver Mechanismus für die Inhibition der Th1- und Th17-Immunantwort verantwortlich sein. Nachfolgende Untersuchungen sind notwendig, um die induzierten immunologischen Mechansimen mittels biolistischer DNA-Vakzinierung aufzuklären. Der zweite Teil der Arbeit befasst sich mit der Generierung von tolerogenen DC in vitro. Dafür wurden murine Knochenmarkszellen unter DC-differenzierenden Bedingungen in Gegenwart des synthetischen Glucocorticoids Dexamethason (DEX) kultiviert. Die DEX-Zugabe führte zur Differenzierung von APC mit geringer CD11c-Expression. DEX-APC waren in vitro weitestgehend gegen LPS stimulierungsresistent und zeigten eine reduzierte Expression von MHC-II und den kostimulatorischen Molekülen CD80, CD86 und CD40. Ihrem tolerogenen Phänotyp entsprechend besaßen DEX-APC ein geringeres syngenes T-Zellstimulierungspotenzial als unbehandelte BM-DC. Anhand der erhöhten Oberflächenexpression von CD11b, GR1 und F4/80 besteht eine phänotypische Ähnlichkeit zu myeloiden Suppressorzellen. Die Fähigkeit von DEX-APC in vivo antigenspezifische Toleranz zu induzieren, wurde durch einen therapeutischen Ansatz im murinen Krankheitsmodell der Kontaktallergie überprüft. Die therapeutische Applikation von DEX-APC führte hierbei im Vergleich zur Applikation von PBS oder unbehandelten BM-DC zu einer signifikant reduzierten Ohrschwellungsreaktion. Zusammenfassend demonstrieren die Ergebnisse dieser Arbeit, dass potente tolerogene DC sowohl in vivo als auch in vitro induziert werden können. Dass diese Zellpopulation effektiv antigenspezifische Immunreaktionen supprimieren kann, macht sie zu einem vielversprechenden Werkzeug in der Behandlung von Autoimmunerkrankungen und Allergien.rn
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The excitation spectrum is one of the fundamental properties of every spatially extended system. The excitations of the building blocks of normal matter, i.e., protons and neutrons (nucleons), play an important role in our understanding of the low energy regime of the strong interaction. Due to the large coupling, perturbative solutions of quantum chromodynamics (QCD) are not appropriate to calculate long-range phenomena of hadrons. For many years, constituent quark models were used to understand the excitation spectra. Recently, calculations in lattice QCD make first connections between excited nucleons and the fundamental field quanta (quarks and gluons). Due to their short lifetime and large decay width, excited nucleons appear as resonances in scattering processes like pion nucleon scattering or meson photoproduction. In order to disentangle individual resonances with definite spin and parity in experimental data, partial wave analyses are necessary. Unique solutions in these analyses can only be expected if sufficient empirical information about spin degrees of freedom is available. The measurement of spin observables in pion photoproduction is the focus of this thesis. The polarized electron beam of the Mainz Microtron (MAMI) was used to produce high-intensity, polarized photon beams with tagged energies up to 1.47 GeV. A "frozen-spin" Butanol target in combination with an almost 4π detector setup consisting of the Crystal Ball and the TAPS calorimeters allowed the precise determination of the helicity dependence of the γp → π0p reaction. In this thesis, as an improvement of the target setup, an internal polarizing solenoid has been constructed and tested. A magnetic field of 2.32 T and homogeneity of 1.22×10−3 in the target volume have been achieved. The helicity asymmetry E, i.e., the difference of events with total helicity 1/2 and 3/2 divided by the sum, was determined from data taken in the years 2013-14. The subtraction of background events arising from nucleons bound in Carbon and Oxygen was an important part of the analysis. The results for the asymmetry E are compared to existing data and predictions from various models. The results show a reasonable agreement to the models in the energy region of the ∆(1232)-resonance but large discrepancies are observed for energy above 600 MeV. The expansion of the present data in terms of Legendre polynomials, shows the sensitivity of the data to partial wave amplitudes up to F-waves. Additionally, a first, preliminary multipole analysis of the present data together with other results from the Crystal Ball experiment has been as been performed.
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In this study we provide a baseline data on semidemersal fish assemblages and biology in a heterogeneous and yet less studied portion of the shelf of Antalya Gulf. The distribution of fish abundance in three transects subjected to different fisheries regulations (fishery vs non fishery areas), and including depths of 10, 25, 75, 125, 200 m, was studied between May 2014 and February 2015 in representative months of winter, spring, summer and autumn seasons. A total of 76 fish species belonging to 40 families was collected and semidemersal species distribution was analyzed in comparison with the whole community. Spatial distribution of fish was driven mainly by depth and two main assemblages were observed: shallow waters (10-25; 75 m) and deep waters (125-200 m). Significant differences among transects were found for the whole community but not for the semidemersal species. Analysis showed that this was due to a strong relation of these species with local environmental characteristics rather than to a different fishing pressure over transects. Firstly all species distribute according to the bathymetrical gradient and secondly to the bottom type structure. Semidemersal species were then found more related to zooplankton and suspended matter availability. The main morphological characteristics, sex and size distribution of the target semidemersal species Spicara smaris (Linnaeus, 1758), Saurida undosquamis (Richardson, 1848), Pagellus acarne (Risso, 1827) were also investigated.
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Non-melanoma skin cancers (NMSCs) are the most common malignancies after solid organ transplantation. Their incidence increases with time after transplantation. Calcineurin-inhibitors (CNIs) and azathioprine are known as skin neoplasia-initiating and -enhancing immunosuppressants. In contrast, increasing clinical experience suggests a relevant antiproliferative effect of mammalian target of rapamycin inhibitors, also named proliferation signal inhibitors (PSIs). We report the case of a cardiac allograft recipient with an impressive and consolidated reduction of recurrent NMSC, observed after conversion from CNI-therapy to a PSI-based protocol.
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PET/CT guidance for percutaneous interventions allows biopsy of suspicious metabolically active bone lesions even when no morphological correlation is delineable in the CT images. Clinical use of PET/CT guidance with conventional step-by-step technique is time consuming and complicated especially in cases in which the target lesion is not shown in the CT image. Our recently developed multimodal instrument guidance system (IGS) for PET/CT improved this situation. Nevertheless, bone biopsies even with IGS have a trade-off between precision and intervention duration which is proportional to patient and personnel exposure to radiation. As image acquisition and reconstruction of PET may take up to 10 minutes, preferably only one time consuming combined PET/CT acquisition should be needed during an intervention. In case of required additional control images in order to check for possible patient movements/deformations, or to verify the final needle position in the target, only fast CT acquisitions should be performed. However, for precise instrument guidance accounting for patient movement and/or deformation without having a control PET image, it is essential to be able to transfer the position of the target as identified in the original PET/CT to a changed situation as shown in the control CT.
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The aim of our study was to investigate the phenomenon of intussusceptive angiogenesis with a focus on its molecular regulation by vascular endothelial growth factor receptor (VEGFR)/platelet-derived growth factor receptor β (PDGFRβ) pathways and biological significance for glomerular recovery after acute injury. Glomerular healing by intussusception was examined in a particular setting of Thy1.1 nephritis, where the lysis of mesangial cells results in an initial collapse and successive rebuilding of glomerular capillary structure. Restoration of capillary structure after induction of Thy1.1 nephritis occurred by intussusceptive angiogenesis resulting in i) rapid expansion of the capillary plexus with reinstatement of the glomerular filtration surface and ii) restoration of the archetypical glomerular vascular pattern. Glomerular capillaries of nephritic rats after combined VEGFR2 and PDGFRβ inhibition by PTK787/ZK222584 (PTK/ZK) were tortuous and irregular. However, the onset of intussusceptive angiogenesis was influenced only after long-term PTK/ZK treatment, providing an important insight into differential molecular regulation between sprouting and intussusceptive angiogenesis. PTK/ZK treatment abolished α-smooth muscle actin and tensin expression by injured mesangial cells, impaired glomerular filtration of microspheres, and led to the reduction of glomerular volume and the presence of multiple hemorrhages detectable in the tubular system. Collectively, treatment of nephritic patients with PTK/ZK compound is not recommended.
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Peroxisome proliferator-activated receptor ? (PPAR?) is a transcription factor that promotes differentiation and cell survival in the stomach. PPAR? upregulates and interacts with caveolin-1 (Cav1), a scaffold protein of Ras/mitogen-activated protein kinases (MAPKs). The cytoplasmic-to-nuclear localization of PPAR? is altered in gastric cancer (GC) patients, suggesting a so-far-unknown role for Cav1 in spatial regulation of PPAR? signaling. We show here that loss of Cav1 accelerated proliferation of normal stomach and GC cells in vitro and in vivo. Downregulation of Cav1 increased Ras/MAPK-dependent phosphorylation of serine 84 in PPAR? and enhanced nuclear translocation and ligand-independent transcription of PPAR? target genes. In contrast, Cav1 overexpression sequestered PPAR? in the cytosol through interaction of the Cav1 scaffolding domain (CSD) with a conserved hydrophobic motif in helix 7 of PPAR?'s ligand-binding domain. Cav1 cooperated with the endogenous Ras/MAPK inhibitor docking protein 1 (Dok1) to promote the ligand-dependent transcriptional activity of PPAR? and to inhibit cell proliferation. Ligand-activated PPAR? also reduced tumor growth and upregulated the Ras/MAPK inhibitors Cav1 and Dok1 in a murine model of GC. These results suggest a novel mechanism of PPAR? regulation by which Ras/MAPK inhibitors act as scaffold proteins that sequester and sensitize PPAR? to ligands, limiting proliferation of gastric epithelial cells.
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Nerve blocks and radiofrequency neurotomy of the nerves supplying the cervical zygapophyseal joints are validated tools for diagnosis and treatment of chronic neck pain, respectively. Unlike fluoroscopy, ultrasound may allow visualization of the target nerves, thereby potentially improving diagnostic accuracy and therapeutic efficacy of the procedures. The aims of this exploratory study were to determine the ultrasound visibility of the target nerves in chronic neck pain patients and to describe the variability of their course in relation to the fluoroscopically used bony landmarks.
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Chronic myelogenous leukemia (CML) results from a chromosomal translocation in hematopoietic stem or early progenitor cells that gives rise to the oncogenic BCR/ABL fusion protein. Clinically, CML has a chronic phase that eventually evolves into an accelerated stage and blast crisis. A CML-specific immune response is thought to contribute to the control of disease. Whether the immune system can also promote disease progression is not known. In the present study, we investigated the possibility that the TNF receptor family member CD27 is present on leukemia stem cells (LSCs) and mediates effects of the immune system on CML. In a mouse model of CML, BCR/ABL+ LSCs and leukemia progenitor cells were found to express CD27. Binding of CD27 by its ligand, CD70, increased expression of Wnt target genes in LSCs by enhancing nuclear localization of active β-catenin and TRAF2- and NCK-interacting kinase (TNIK). This resulted in increased proliferation and differentiation of LSCs. Blocking CD27 signaling in LSCs delayed disease progression and prolonged survival. Furthermore, CD27 was expressed on CML stem/progenitor cells in the bone marrow of CML patients, and CD27 signaling promoted growth of BCR/ABL+ human leukemia cells by activating the Wnt pathway. Since expression of CD70 is limited to activated lymphocytes and dendritic cells, our results reveal a mechanism by which adaptive immunity contributes to leukemia progression. In addition, targeting CD27 on LSCs may represent an attractive therapeutic approach to blocking the Wnt/β-catenin pathway in CML.
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Sirtuins and hypoxia-inducible transcription factors (HIF) have well-established roles in regulating cellular responses to metabolic and oxidative stress. Recent reports have linked these two protein families by demonstrating that sirtuins can regulate the activity of HIF-1 and HIF-2. Here we investigated the role of SIRT1, a NAD+-dependent deacetylase, in the regulation of HIF-1 activity in hypoxic conditions. Our results show that in hepatocellular carcinoma (HCC) cell lines, hypoxia did not alter SIRT1 mRNA or protein expression, whereas it predictably led to the accumulation of HIF-1α and the up-regulation of its target genes. In hypoxic models in vitro and in in vivo models of systemic hypoxia and xenograft tumor growth, knockdown of SIRT1 protein with shRNA or inhibition of its activity with small molecule inhibitors impaired the accumulation of HIF-1α protein and the transcriptional increase of its target genes. In addition, endogenous SIRT1 and HIF-1α proteins co-immunoprecipitated and loss of SIRT1 activity led to a hyperacetylation of HIF-1α. Taken together, our data suggest that HIF-1α and SIRT1 proteins interact in HCC cells and that HIF-1α is a target of SIRT1 deacetylase activity. Moreover, SIRT1 is necessary for HIF-1α protein accumulation and activation of HIF-1 target genes under hypoxic conditions.
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If you had perfect pitch and listened to a recording of the sounds a drum made when struck, could you determine the shape of the drum? This question is an example of an inverse problem; inverse problems arise in medical imaging, oil prospecting, spectroscopy, and many other fields. We’ll first discuss the analogous question in the simpler setting of plucking a string. Then we’ll tackle the problem for drums and see that there are some surprises. Finally, I will give a brief indication of how this problem relates to some of my recent research. The emphasis will be on the ideas rather than on the technical details, so there will be pretty pictures instead of equations.