894 resultados para dual-specificity phosphatases
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A control-oriented model of a Dual Clutch Transmission was developed for real-time Hardware In the Loop (HIL) applications, to support model-based development of the DCT controller. The model is an innovative attempt to reproduce the fast dynamics of the actuation system while maintaining a step size large enough for real-time applications. The model comprehends a detailed physical description of hydraulic circuit, clutches, synchronizers and gears, and simplified vehicle and internal combustion engine sub-models. As the oil circulating in the system has a large bulk modulus, the pressure dynamics are very fast, possibly causing instability in a real-time simulation; the same challenge involves the servo valves dynamics, due to the very small masses of the moving elements. Therefore, the hydraulic circuit model has been modified and simplified without losing physical validity, in order to adapt it to the real-time simulation requirements. The results of offline simulations have been compared to on-board measurements to verify the validity of the developed model, that was then implemented in a HIL system and connected to the TCU (Transmission Control Unit). Several tests have been performed: electrical failure tests on sensors and actuators, hydraulic and mechanical failure tests on hydraulic valves, clutches and synchronizers, and application tests comprehending all the main features of the control performed by the TCU. Being based on physical laws, in every condition the model simulates a plausible reaction of the system. The first intensive use of the HIL application led to the validation of the new safety strategies implemented inside the TCU software. A test automation procedure has been developed to permit the execution of a pattern of tests without the interaction of the user; fully repeatable tests can be performed for non-regression verification, allowing the testing of new software releases in fully automatic mode.
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The present dissertation focuses on the dual number in Ancient Greek in a diachronical lapse stretching from the Mycenaean age to the Attic Drama and Comedy of the 5th century BC. In the first chapter morphological issues are addressed, chiefly in a comparative perspective. The Indo European evidence on the dual is hence gathered in order to sketch patterns of grammaticalisation and paradigmatisation of specific grams, growing increasingly functional within the Greek domain. In the second chapter syntactical problems are tackled. After a survey of scholarly literature on the Greek dual, we engage in a functional and typological approach, in order to disentangle some biased assessments on the dual, namely its alleged lack of regularity and intermittent agreement. Some recent frameworks in General Linguistics provide useful grounds for casting new light on the subject. Internal Reconstruction, for instance, supports the facultativity of the dual in each and every stage of its development; Typology and the Animacy Hierarcy add precious cross linguistical insight on the behaviour of the dual toward agreement. Glaring differences also arise as to the adoption — or avoidance — of the dual by different authors. Idiolectal varieties prove in fact conditioned by stylistical and register necessity. By means of a comparison among Epics, Tragedy and Comedy it is possible to enhance differences in the evaluation of the dual, which led sometimes to forms of ‘censure’ — thus triggering the onset of competing strategies to express duality. The last two chapters delve into the tantalising variety of the Homeric evidence, first of all in an account of the notorious issue of the Embassy of Iliad IX, and last in a commentary of all significant Homeric duals — mostly represented by archaisms, formulae, and ad hoc coinages.
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Die akute myeloische Leukämie (AML) zählt zu den aggressivsten neoplastischen Erkrankungenrnder Hämatopoese. Die Mehrheit der Patienten mit AML erreicht nach Induktions-rnChemotherapie den Zustand der kompletten Remission, jedoch erleiden mehr als die Hälfterndieser Patienten anschließend einen Rückfall und versterben an den Folgen der Erkrankungrn[1]. Die allogene hämatopoetische Stammzelltransplantation (engl.: hematopoietic stem cellrntransplantation, HSCT) stellt die einzig putativ kurative Behandlungsform für rezidierendernPatienten und solche mit schlechter Prognose dar. Jedoch birgt diese Form der Therapiernauch eine Vielzahl an Risiken. Insbesondere das Auftreten einer akuten Transplantat-gegen-rnWirt-Erkrankung (engl.: graft-versus-host disease, GvHD) stellt die Hauptursache für transplantationsassoziierternMortalität und Morbidität dar [2]. Die Depletion von alloreaktiven zytotoxischenrnT Lymphozyten (CTL) aus dem Transplantat ermöglicht zwar die Prävention derrnEntstehung einer GvH-Erkrankung, jedoch häufig unter gleichzeitigem Verlust des förderlichen,rnanti-leukämischen Transplantat-gegen-Leukämie-Effekts (engl.: graft-versus-leukemia,rnGvL) [3]. Um den GvL-Effekt unter Vermeidung einer GvH-Erkrankung zu erhalten, bietetrnsich der gezielte adoptive Transfer von Leukämie-spezifischen, nicht alloreaktiven CTL alsrnattraktive Strategie der Immuntherapie für AML-Patienten nach allogener HSCT an. In derrnvorliegenden Arbeit konnte erfolgreich ein prä-klinisches murines AML-Modell unter Einsatzrndes stark immundefizienten NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ- (NSG-) Mausstamms und primärenrnAML-Blasten durch die Optimierung bereits publizierter Protokolle etabliert werden.rnBei zehn von 17 transplantierten primären AML-Proben konnte ein erfolgreiches Engraftmentrnder humanen Zellen und eine Rekonstitution der humanen Neoplasie in den NSG-Mäusenrnerzielt werden. Die Engraftment-Rate betrug somit 58,82% und lag etwas unter dem aus derrnLiteratur bekannten Wert von 65-70% [4, 5]. Es ließen sich gut, intermediär und schlecht anwachsendernAML-Proben anhand der Engraftment-Stärke und -Reproduzierbarkeit voneinanderrnunterscheiden. Anhand der Analyse von für das Engraftment kritischer Parameter konnternein Zusammenhang zwischen Engraftment-Rate in der Maus und Flt3-Mutationsstatus sowiernFAB-Klassifikation des Patienten hergestellt und somit Angaben aus der Literatur bestätigtrnwerden. Für zwei Patienten-spezifische AML-Modelle, MZ580 und MZ308, konnten in vitrornerfolgreich AML-reaktive, über einzelne bzw. duale HLA-Diskrepanzen restringierte CTLPopulationenrngeneriert und über einen Zeitraum von bis zu 70 Tagen expandiert werden.rnDeren adoptiver Transfer in zuvor mit humanen AML-Blasten inokulierte NSG-Mäuse führternzu einer nahezu vollständigen Eradikation der AML-Blasten und Remission der Versuchstiere.rnAnhand unterschiedlich langer in vitro Kultur-Zeiträume konnte ein für die in vivo ausgeübtenrnEffektor-Funktionen optimaler Reifungszustand der CTL-Populationen von maximalrn28 Tagen bestimmt werden. Die kinetische Analyse der lytischen Aktivität in vivo deutete auf eine relativ schnelle Ausübung der Effektor-Funktionen durch die CTL-Populationen innerhalbrnvon zwei bis 24 Stunden nach adoptivem Transfer hin. Durch die Verwendung von inrnvitro generierten EBV-reaktiven CTL aus einem irrelevanten Spender konnte zudem die Spezifitätrnder in vivo ausgeübten Effektor-Funktionen nachgewiesen werden. Die ex vivo Re-rnIsolation adoptiv transferierter CTL und deren in vitro Analyse in einem IFNγ ELISpot wiesrneine konstante Reaktivität der Zellen ohne Induktion einer Xeno-Reaktivität nach. Die zurrnVerbesserung der Persistenz humaner CTL-Populationen eingesetzten autologen CD4+ TrnZellen zeigten nur im AML MZ308-System eine positive Wirkung. Generell konnte die Persistenzrnin vivo jedoch trotz initialer Substitution mit den Zytokinen IL-2 und IL-7 nicht über einenrnZeitraum von sieben Tagen hinaus aufrechterhalten werden.rnZur Untersuchung des Extravasations-Mechanismus humaner T Zellen über murines Endothelrnwurden sowohl Flusskammer- als auch Transwell-Studien durchgeführt, um die molekularenrnGrundlagen des Adhäsions- und Transmigrationsprozesses aufzuklären. Durch denrnparallelen Einsatz humaner und muriner T Zellen auf murinen Endothelzellen unter Zusatzrnfunktionsblockierender monoklonaler Antikörper konnte gezeigt werden, dass derrnExtravasations-Mechanismus beider Spezies auf Interaktionen homologer Adhäsionsmolekül-rnPaare, nämlich VLA-4–VCAM-1 und LFA-1–ICAM-1, beruht. Für einzelne Moleküle konntenrnin Abhängigkeit der eingesetzten Endothelzellen Unterschiede in der Funktionalität zwischenrnden Spezies identifiziert werden. Der Adhäsionsprozess war durch die Blockade derrnVLA-4–VCAM-1-Interaktion stärker inhibierbar als durch die Blockade von LFA-1–ICAM-1.rnDie Transmigration hingegen war durch die Blockade beider Adhäsionsmolekül-Paare vergleichbarrnstark inhibierbar.
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Due to multiple immune evasion mechanisms of cancer cells, novel therapy approaches are required to overcome the limitations of existing immunotherapies. Bispecific antibodies are potent anti-cancer drugs, which redirect effector T cells for specific tumor cell lysis, thus enabling the patient’s immune system to fight cancer cells. The antibody format used in this proof of concept study–bispecific ideal monoclonal antibodies termed BiMAB–is a tailor-made recombinant protein, which consists of two fused scFv antibodies recognizing different antigens. Both are arranged in tandem on a single peptide chain and the individual variable binding domains are separated by special non-immunogenic linkers. The format is comprised of a scFv targeting CLDN18.2–a gastric cancer tumor associated antigen (TAA) –while the second specificity binds the CD3 epsilon (CD3ε) subunit of the T cell receptor (TCR) on T cells. For the first time, we compared in our IMAB362-based BiMAB setting, four different anti-CD3-scFvs, respectively derived from the mAbs TR66, CLB-T3, as well as the humanized and the murine variant of UCHT1. In addition, we investigated the impact of an N- versus a C-terminal location of the IMAB362-derived scFv and the anti-CD3-scFvs. Thus, nine CLDN18.2 specific BiMAB proteins were generated, of which all showed a remarkably high cytotoxicity towards CLDN18.2-positive tumor cells. Because of its promising effectiveness, 1BiMAB emerged as the BiMAB prototype. The selectivity of 1BiMAB for its TAA and CD3ε, with affinities in the nanomolar range, has been confirmed by in vitro assays. Its dual binding depends on the design of an N-terminally positioned IMAB362 scFv and the consecutive C-terminally positioned TR66 scFv. 1BiMAB provoked a concentration and target cell dependent T cell activation, proliferation, and upregulation of the cytolytic protein Granzyme B, as well as the consequent elimination of target cells. Our results demonstrate that 1BiMAB is able to activate T cells independent of elements that are usually involved in the T cell recognition program, like antigen presentation, MHC restriction, and co-stimulatory effector molecules. In the first in vivo studies using a subcutaneous xenogeneic tumor mouse model in immune incompetent NSG mice, we could prove a significant therapeutic effect of 1BiMAB with partial or complete tumor elimination. The initial in vitro RIBOMAB experiments correspondingly showed encouraging results. The electroporation of 1BiMAB IVT-RNA into target or effector cells was feasible, while the functionality of translated 1BiMAB was proven by induced T cell activation and target cell lysis. Accordingly, we could show that the in vitro RIBOMAB approach was applicable for all nine BiMABs, which proves the RIBOMAB concept. Thus, the CLDN18.2-BiMAB strategy offers great potential for the treatment of cancer. In the future, administered either as protein or as IVT-RNA, the BiMAB format will contribute towards finding solutions to raise and sustain tumor-specific cellular responses elicited by engaged and activated endogenous T cells. This will potentially enable us to overcome immune evasion mechanisms of tumor cells, consequently supporting current solid gastric cancer therapies.
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Adoptive T cell therapy using antigen-specific T lymphocytes is a powerful immunotherapeutic approach against cancer. Nevertheless, many T cells against tumor-antigens exhibit only weak anti-tumoral response. To overcome this barrier it is necessary to improve the potency and anti-tumoral efficacy of these T cells. Activation and activity of T cells are tightly controlled to inhibit unwanted T cell responses and to reduce the risk of autoimmunity. Both are regulated by extrinsic signals and intrinsic mechanisms which suppress T cell activation. The intrinsic mechanisms include the expression of phosphatases that counteract the activation-inducing kinases. Modifying the expression of these phosphatases allows the targeted modulation of T cell reactivity. MicroRNAs (miRNAs) are regulatory small noncoding RNA molecules that control gene expression by targeting messenger RNAs in a sequence specific manner. Gene-specific silencing plays a key role in diverse biological processes, such as development, differentiation, and functionality. miR181a has been shown to be highly expressed in immature T cells that recognize low-affinity antigens.rnThe present study successfully shows that ectopic expression of miR181a is able to enhance the sensitivity of both murine and human T cells. In CD4+ T helper cells as well as in CD8+ cytotoxic T cells the overexpression of miR181a leads to downregulation of multiple phosphatases involved in the T cell receptor signaling pathway. Overexpression of miR181a in human T cells achieves a co-stimulatory independent activation and has an anti-apoptotic effect on CD4+ T helper cells. Additionally, increasing the amount of miR181a enhances the cytolytic activity of murine CD8+ TCRtg T cells in an antigen-specific manner.rnTo test miR181a overexpressing T cells in vivo, a mouse tumor model using a B cell lymphoma cell line (A20-HA) expressing the Influenza hemagglutinin (Infl.-HA) antigen was established. The expression of model antigens in tumor cell lines enables targeted elimination of tumors using TCRtg T cells. The transfer of miR181a overexpressing Infl.-HA TCRtg CD8+ T cells alone has no positive effect neither on tumor control nor on survival of A20-HA tumor-bearing mice. In contrast, the co-transfer of miR181a overexpressing Infl.-HA TCRtg CD8+ and CD4+ T cells leads to improved tumor control and prolongs survival of A20-HA tumor-bearing mice. This effect is characterized by higher amounts of effector T cells and the expansion of Infl.-HA TCRtg CD8+ T cells.rnAll effects were achieved by changes in expression of several genes including molecules involved in T cell differentiation, activation, and regulation, cytotoxic effector molecules, and receptors important for the homing process of T cells in miR181a overexpressing T cells. The present study demonstrates that miR181a is able to enhance the anti-tumoral response of antigen-specific T cells and is a promising candidate for improving adoptive cell therapy.
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Nel presente lavoro è progettato e sviluppato un sistema dual-fuel diesel/benzina per combustioni di tipo RCCI, e sono esposti i risultati sperimentali in termini di prestazioni ed emissioni. E' inoltre descritto e implementato un algoritmo di stima dell'MFB50 a partire dalla sola misura della velocità motore.
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Il crescente utilizzo di sistemi di analisi high-throughput per lo studio dello stato fisiologico e metabolico del corpo, ha evidenziato che una corretta alimentazione e una buona forma fisica siano fattori chiave per la salute. L'aumento dell'età media della popolazione evidenzia l'importanza delle strategie di contrasto delle patologie legate all'invecchiamento. Una dieta sana è il primo mezzo di prevenzione per molte patologie, pertanto capire come il cibo influisce sul corpo umano è di fondamentale importanza. In questo lavoro di tesi abbiamo affrontato la caratterizzazione dei sistemi di imaging radiografico Dual-energy X-ray Absorptiometry (DXA). Dopo aver stabilito una metodologia adatta per l'elaborazione di dati DXA su un gruppo di soggetti sani non obesi, la PCA ha evidenziato alcune proprietà emergenti dall'interpretazione delle componenti principali in termini delle variabili di composizione corporea restituite dalla DXA. Le prime componenti sono associabili ad indici macroscopici di descrizione corporea (come BMI e WHR). Queste componenti sono sorprendentemente stabili al variare dello status dei soggetti in età, sesso e nazionalità. Dati di analisi metabolica, ottenuti tramite Magnetic Resonance Spectroscopy (MRS) su campioni di urina, sono disponibili per circa mille anziani (provenienti da cinque paesi europei) di età compresa tra i 65 ed i 79 anni, non affetti da patologie gravi. I dati di composizione corporea sono altresì presenti per questi soggetti. L'algoritmo di Non-negative Matrix Factorization (NMF) è stato utilizzato per esprimere gli spettri MRS come combinazione di fattori di base interpretabili come singoli metaboliti. I fattori trovati sono stabili, quindi spettri metabolici di soggetti sono composti dallo stesso pattern di metaboliti indipendentemente dalla nazionalità. Attraverso un'analisi a singolo cieco sono stati trovati alti valori di correlazione tra le variabili di composizione corporea e lo stato metabolico dei soggetti. Ciò suggerisce la possibilità di derivare la composizione corporea dei soggetti a partire dal loro stato metabolico.
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To assess the sensitivity and image quality of chest radiography (CXR) with or without dual-energy subtracted (ES) bone images in the detection of rib fractures.
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To report our initial experience with dual-energy computed-tomography (CT) cholangiography in potential donors for living-related liver transplantation.
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To prospectively evaluate a 3-dimensional spoiled gradient-dual-echo (3D SPGR-DE) magnetic resonance imaging (MRI) sequence for the qualitative and quantitative analysis of liver fat content (LFC) in patients with the suspicion of fatty liver disease using histopathology as the standard of reference.
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Positron emission tomography (PET) has proven to be a clinically valuable imaging modality, particularly for oncology staging and therapy follow-up. The introduction of combined PET/CT imaging has helped address challenging imaging situations when anatomical information on PET-only was inadequate for accurate lesion localization. After a decade of PET/CT these combined systems have matured technically. Today, whole-body oncology staging is available with PET/CT in 15 min, or less. This review details recent developments in combined PET/CT instrumentation and points to implications for major applications in clinical oncology.
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Impaired response to antiplatelet therapy with acetylsalicylic acid (ASA) and clopidogrel (CLO) has been associated with an increased risk of stent thrombosis and ischemic events after coronary stent implantation. We sought to investigate whether patients with a low response (LR) to ASA or CLO are at increased risk for periprocedural and short-term ischemic events after coronary stent implantation.
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Drug-drug interaction between statins metabolised by cytochrome P450 3A4 and clopidogrel have been claimed to attenuate the inhibitory effect of clopidogrel. However, published data regarding this drug-drug interaction are controversial. We aimed to determine the effect of fluvastatin and atorvastatin on the inhibitory effect of dual antiplatelet therapy with acetylsalicylic acid (ASA) and clopidogrel. One hundred one patients with symptomatic stable coronary artery disease undergoing percutaneous coronary intervention and drug-eluting stent implantation were enrolled in this prospective randomised study. After an interval of two weeks under dual antiplatelet therapy with ASA and clopidogrel, without any lipid-lowering drug, 87 patients were randomised to receive a treatment with either fluvastatin 80 mg daily or atorvastatin 40 mg daily in addition to the dual antiplatelet therapy for one month. Platelet aggregation was assessed using light transmission aggregometry and whole blood impedance platelet aggregometry prior to randomisation and after one month of receiving assigned statin and dual antiplatelet treatment. Platelet function assessment after one month of statin and dual antiplatelet therapy did not show a significant change in platelet aggregation from 1st to 2nd assessment for either statin group. There was also no difference between atorvastatin and fluvastatin treatment arms. In conclusion, neither atorvastatin 40 mg daily nor fluvastatin 80 mg daily administered in combination with standard dual antiplatelet therapy following coronary drug-eluting stent implantation significantly interfere with the antiaggregatory effect of ASA and clopidogrel.
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Host determinants of HIV-1 viral tropism include factors from producer cells that affect the efficiency of productive infection and factors in target cells that block infection after viral entry. TRIM5 restricts HIV-1 infection at an early post-entry step through a mechanism associated with rapid disassembly of the retroviral capsid. Topoisomerase I (TOP1) appears to play a role in HIV-1 viral tropism by incorporating into or otherwise modulating virions affecting the efficiency of a post-entry step, as the expression of human TOP1 in African Green Monkey (AGM) virion-producing cells increased the infectivity of progeny virions by five-fold. This infectivity enhancement required human TOP1 residues 236 and 237 as their replacement with the AGM counterpart residues abolished the infectivity enhancement. Our previous studies showed that TOP1 interacts with BTBD1 and BTBD2, two proteins which co-localize with the TRIM5 splice variant TRIM5 in cytoplasmic bodies. Because BTBD1 and BTBD2 interact with one HIV-1 viral tropism factor, TOP1, and co-localize with a splice variant of another, we investigated the potential involvement of BTBD1 and BTBD2 in HIV-1 restriction.