883 resultados para Pre-clinical tests


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[EN] Background: Either higher levels of initial DNA damage or lower levels of radiation-induced apoptosis in peripheral blood lymphocytes have been associated to increased risk for develop late radiation-induced toxicity. It has been recently published that these two predictive tests are inversely related. The aim of the present study was to investigate the combined role of both tests in relation to clinical radiation-induced toxicity in a set of breast cancer patients treated with high dose hyperfractionated radical radiotherapy. Methods: Peripheral blood lymphocytes were taken from 26 consecutive patients with locally advanced breast carcinoma treated with high-dose hyperfractioned radical radiotherapy. Acute and late cutaneous and subcutaneous toxicity was evaluated using the Radiation Therapy Oncology Group morbidity scoring schema. The mean follow-up of survivors (n = 13) was 197.23 months. Radiosensitivity of lymphocytes was quantified as the initial number of DNA double-strand breaks induced per Gy and per DNA unit (200 Mbp). Radiation-induced apoptosis (RIA) at 1, 2 and 8 Gy was measured by flow cytometry using annexin V/propidium iodide. Results: Mean DSB/Gy/DNA unit obtained was 1.70 ± 0.83 (range 0.63-4.08; median, 1.46). Radiation-induced apoptosis increased with radiation dose (median 12.36, 17.79 and 24.83 for 1, 2, and 8 Gy respectively). We observed that those "expected resistant patients" (DSB values lower than 1.78 DSB/Gy per 200 Mbp and RIA values over 9.58, 14.40 or 24.83 for 1, 2 and 8 Gy respectively) were at low risk of suffer severe subcutaneous late toxicity (HR 0.223, 95%CI 0.073-0.678, P = 0.008; HR 0.206, 95%CI 0.063-0.677, P = 0.009; HR 0.239, 95%CI 0.062-0.929, P = 0.039, for RIA at 1, 2 and 8 Gy respectively) in multivariate analysis. Conclusions: A radiation-resistant profile is proposed, where those patients who presented lower levels of initial DNA damage and higher levels of radiation induced apoptosis were at low risk of suffer severe subcutaneous late toxicity after clinical treatment at high radiation doses in our series. However, due to the small sample size, other prospective studies with higher number of patients are needed to validate these results.

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[EN] Head and neck cancer is treated mainly by surgery and radiotherapy. Normal tissue toxicity due to x-ray exposure is a limiting factor for treatment success. Many efforts have been employed to develop predictive tests applied to clinical practice. Determination of lymphocyte radio-sensitivity by radio-induced apoptosis arises as a possible method to predict tissue toxicity due to radiotherapy. The aim of the present study was to analyze radio-induced apoptosis of peripheral blood lymphocytes in head and neck cancer patients and to explore their role in predicting radiation induced toxicity. Seventy nine consecutive patients suffering from head and neck cancer, diagnosed and treated in our institution, were included in the study. Toxicity was evaluated using the Radiation Therapy Oncology Group scale. Peripheral blood lymphocytes were isolated and irradiated at 0, 1, 2 and 8 Gy during 24 hours. Apoptosis was measured by flow cytometry using annexin V/propidium iodide. Lymphocytes were marked with CD45 APC-conjugated monoclonal antibody. Radiation-induced apoptosis increased in order to radiation dose and fitted to a semi logarithmic model defined by two constants: α and β. α, as the origin of the curve in the Y axis determining the percentage of spontaneous cell death, and β, as the slope of the curve determining the percentage of cell death induced at a determined radiation dose, were obtained. β value was statistically associated to normal tissue toxicity in terms of severe xerostomia, as higher levels of apoptosis were observed in patients with low toxicity (p = 0.035; Exp(B) 0.224, I.C.95% (0.060-0.904)). These data agree with our previous results and suggest that it is possible to estimate the radiosensitivity of peripheral blood lymphocytes from patients determining the radiation induced apoptosis with annexin V/propidium iodide staining. β values observed define an individual radiosensitivity profile that could predict late toxicity due to radiotherapy in locally advanced head and neck cancer patients. Anyhow, prospective studies with different cancer types and higher number of patients are needed to validate these results.

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Primary stability of stems in cementless total hip replacements is recognized to play a critical role for long-term survival and thus for the success of the overall surgical procedure. In Literature, several studies addressed this important issue. Different approaches have been explored aiming to evaluate the extent of stability achieved during surgery. Some of these are in-vitro protocols while other tools are coinceived for the post-operative assessment of prosthesis migration relative to the host bone. In vitro protocols reported in the literature are not exportable to the operating room. Anyway most of them show a good overall accuracy. The RSA, EBRA and the radiographic analysis are currently used to check the healing process of the implanted femur at different follow-ups, evaluating implant migration, occurance of bone resorption or osteolysis at the interface. These methods are important for follow up and clinical study but do not assist the surgeon during implantation. At the time I started my Ph.D Study in Bioengineering, only one study had been undertaken to measure stability intra-operatively. No follow-up was presented to describe further results obtained with that device. In this scenario, it was believed that an instrument that could measure intra-operatively the stability achieved by an implanted stem would consistently improve the rate of success. This instrument should be accurate and should give to the surgeon during implantation a quick answer concerning the stability of the implanted stem. With this aim, an intra-operative device was designed, developed and validated. The device is meant to help the surgeon to decide how much to press-fit the implant. It is essentially made of a torsional load cell, able to measure the extent of torque applied by the surgeon to test primary stability, an angular sensor that measure the relative angular displacement between stem and femur, a rigid connector that enable connecting the device to the stem, and all the electronics for signals conditioning. The device was successfully validated in-vitro, showing a good overall accuracy in discriminating stable from unstable implants. Repeatability tests showed that the device was reliable. A calibration procedure was then performed in order to convert the angular readout into a linear displacement measurement, which is an information clinically relevant and simple to read in real-time by the surgeon. The second study reported in my thesis, concerns the evaluation of the possibility to have predictive information regarding the primary stability of a cementless stem, by measuring the micromotion of the last rasp used by the surgeon to prepare the femoral canal. This information would be really useful to the surgeon, who could check prior to the implantation process if the planned stem size can achieve a sufficient degree of primary stability, under optimal press fitting conditions. An intra-operative tool was developed to this aim. It was derived from a previously validated device, which was adapted for the specific purpose. The device is able to measure the relative micromotion between the femur and the rasp, when a torsional load is applied. An in-vitro protocol was developed and validated on both composite and cadaveric specimens. High correlation was observed between one of the parameters extracted form the acquisitions made on the rasp and the stability of the corresponding stem, when optimally press-fitted by the surgeon. After tuning in-vitro the protocol as in a closed loop, verification was made on two hip patients, confirming the results obtained in-vitro and highlighting the independence of the rasp indicator from the bone quality, anatomy and preserving conditions of the tested specimens, and from the sharpening of the rasp blades. The third study is related to an approach that have been recently explored in the orthopaedic community, but that was already in use in other scientific fields. It is based on the vibration analysis technique. This method has been successfully used to investigate the mechanical properties of the bone and its application to evaluate the extent of fixation of dental implants has been explored, even if its validity in this field is still under discussion. Several studies have been published recently on the stability assessment of hip implants by vibration analysis. The aim of the reported study was to develop and validate a prototype device based on the vibration analysis technique to measure intra-operatively the extent of implant stability. The expected advantages of a vibration-based device are easier clinical use, smaller dimensions and minor overall cost with respect to other devices based on direct micromotion measurement. The prototype developed consists of a piezoelectric exciter connected to the stem and an accelerometer attached to the femur. Preliminary tests were performed on four composite femurs implanted with a conventional stem. The results showed that the input signal was repeatable and the output could be recorded accurately. The fourth study concerns the application of the device based on the vibration analysis technique to several cases, considering both composite and cadaveric specimens. Different degrees of bone quality were tested, as well as different femur anatomies and several levels of press-fitting were considered. The aim of the study was to verify if it is possible to discriminate between stable and quasi-stable implants, because this is the most challenging detection for the surgeon in the operation room. Moreover, it was possible to validate the measurement protocol by comparing the results of the acquisitions made with the vibration-based tool to two reference measurements made by means of a validated technique, and a validated device. The results highlighted that the most sensitive parameter to stability is the shift in resonance frequency of the stem-bone system, showing high correlation with residual micromotion on all the tested specimens. Thus, it seems possible to discriminate between many levels of stability, from the grossly loosened implant, through the quasi-stable implants, to the definitely stable one. Finally, an additional study was performed on a different type of hip prosthesis, which has recently gained great interest thus becoming fairly popular in some countries in the last few years: the hip resurfacing prosthesis. The study was motivated by the following rationale: although bone-prosthesis micromotion is known to influence the stability of total hip replacement, its effect on the outcome of resurfacing implants has not been investigated in-vitro yet, but only clinically. Thus the work was aimed at verifying if it was possible to apply to the resurfacing prosthesis one of the intraoperative devices just validated for the measurement of the micromotion in the resurfacing implants. To do that, a preliminary study was performed in order to evaluate the extent of migration and the typical elastic movement for an epiphyseal prosthesis. An in-vitro procedure was developed to measure micromotions of resurfacing implants. This included a set of in-vitro loading scenarios that covers the range of directions covered by hip resultant forces in the most typical motor-tasks. The applicability of the protocol was assessed on two different commercial designs and on different head sizes. The repeatability and reproducibility were excellent (comparable to the best previously published protocols for standard cemented hip stems). Results showed that the procedure is accurate enough to detect micromotions of the order of few microns. The protocol proposed was thus completely validated. The results of the study demonstrated that the application of an intra-operative device to the resurfacing implants is not necessary, as the typical micromovement associated to this type of prosthesis could be considered negligible and thus not critical for the stabilization process. Concluding, four intra-operative tools have been developed and fully validated during these three years of research activity. The use in the clinical setting was tested for one of the devices, which could be used right now by the surgeon to evaluate the degree of stability achieved through the press-fitting procedure. The tool adapted to be used on the rasp was a good predictor of the stability of the stem. Thus it could be useful for the surgeon while checking if the pre-operative planning was correct. The device based on the vibration technique showed great accuracy, small dimensions, and thus has a great potential to become an instrument appreciated by the surgeon. It still need a clinical evaluation, and must be industrialized as well. The in-vitro tool worked very well, and can be applied for assessing resurfacing implants pre-clinically.

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The interactions between outdoor bronzes and the environment, which lead to bronze corrosion, require a better understanding in order to design effective conservation strategies in the Cultural Heritage field. In the present work, investigations on real patinas of the outdoor monument to Vittorio Bottego (Parma, Italy) and laboratory studies on accelerated corrosion testing of inhibited (by silane-based films, with and without ceria nanoparticles) and non-inhibited quaternary bronzes are reported and discussed. In particular, a wet&dry ageing method was used both for testing the efficiency of the inhibitor and for patinating bronze coupons before applying the inhibitor. A wide range of spectroscopic techniques has been used, for characterizing the core metal (SEM+EDS, XRF, AAS), the corroded surfaces (SEM+EDS, portable XRF, micro-Raman, ATR-IR, Py-GC-MS) and the ageing solutions (AAS). The main conclusions were: 1. The investigations on the Bottego monument confirmed the differentiation of the corrosion products as a function of the exposure geometry, already observed in previous works, further highlighting the need to take into account the different surface features when selecting conservation procedures such as the application of inhibitors (i.e. the relative Sn enrichment in unsheltered areas requires inhibitors which effectively interact not only with Cu but also with Sn). 2. The ageing (pre-patination) cycle on coupons was able to reproduce the relative Sn enrichment that actually happens in real patinated surfaces, making the bronze specimens representative of the real support for bronze inhibitors. 3. The non-toxic silane-based inhibitors display a good protective efficiency towards pre-patinated surfaces, differently from other widely used inhibitors such as benzotriazole (BTA) and its derivatives. 4. The 3-mercapto-propyl-trimethoxy-silane (PropS-SH) additivated with CeO2 nanoparticles generally offered a better corrosion protection than PropS-SH.

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Il trauma cranico é tra le piú importanti patologie traumatiche. Ogni anno 250 pazienti ogni 100.000 abitanti vengono ricoverati in Italia per un trauma cranico. La mortalitá é di circa 17 casi per 100.000 abitanti per anno. L’Italia si trova in piena “media” Europea considerando l’incidenza media in Europa di 232 casi per 100.000 abitanti ed una mortalitá di 15 casi per 100.000 abitanti. Degli studi hanno indicato come una terapia anticoagulante é uno dei principali fattori di rischio di evolutiviá di una lesione emorragica. Al contrario della terapia anticoagulante, il rischio emorragico correlato ad una terapia antiaggregante é a tutt’oggi ancora in fase di verifica. Il problema risulta rilevante in particolare nella popolazione occidentale in quanto l’impiego degli antiaggreganti é progressivamente sempre piú diffuso. Questo per la politica di prevenzione sostenuta dalle linee guida nazionali e internazionali in termini di prevenzione del rischio cardiovascolare, in particolare nelle fasce di popolazione di etá piú avanzata. Per la prima volta, é stato dimostrato all’ospedale di Forlí[1], su una casistica sufficientemente ampia, che la terapia cronica con antiaggreganti, per la preven- zione del rischio cardiovascolare, puó rivelarsi un significativo fattore di rischio di complicanze emorragiche in un soggetto con trauma cranico, anche di grado lieve. L’ospedale per approfondire e convalidare i risultati della ricerca ha condotto, nell’anno 2009, una nuova indagine. La nuova indagine ha coinvolto oltre l’ospedale di Forlí altri trentuno centri ospedalieri italiani. Questo lavoro di ricerca vuole, insieme ai ricercatori dell’ospedale di Forlí, verificare: “se una terapia con antiaggreganti influenzi l’evolutivitá, in senso peggiorativo, di una lesione emorragica conseguente a trauma cranico lieve - moderato - severo in un soggetto adulto”, grazie ai dati raccolti dai centri ospedalieri nel 2009. Il documento é strutturato in due parti. La prima parte piú teorica, vuole fissare i concetti chiave riguardanti il contesto della ricerca e la metodologia usata per analizzare i dati. Mentre, la seconda parte piú pratica, vuole illustrare il lavoro fatto per rispondere al quesito della ricerca. La prima parte é composta da due capitoli, che sono: • Il capitolo 1: dove sono descritti i seguenti concetti: cos’é un trauma cra- nico, cos’é un farmaco di tipo anticoagulante e cos’é un farmaco di tipo antiaggregante; • Il capitolo 2: dove é descritto cos’é il Data Mining e quali tecniche sono state usate per analizzare i dati. La seconda parte é composta da quattro capitoli, che sono: • Il capitolo 3: dove sono state descritte: la struttura dei dati raccolti dai trentadue centri ospedalieri, la fase di pre-processing e trasformazione dei dati. Inoltre in questo capitolo sono descritti anche gli strumenti utilizzati per analizzare i dati; • Il capitolo 4: dove é stato descritto come é stata eseguita l’analisi esplorativa dei dati. • Il capitolo 5: dove sono descritte le analisi svolte sui dati e soprattutto i risultati che le analisi, grazie alle tecniche di Data Mining, hanno prodotto per rispondere al quesito della ricerca; • Il capitolo 6: dove sono descritte le conclusioni della ricerca. Per una maggiore comprensione del lavoro sono state aggiunte due appendici. La prima tratta del software per data mining Weka, utilizzato per effettuare le analisi. Mentre, la seconda tratta dell’implementazione dei metodi per la creazione degli alberi decisionali.

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Advances in biomedical signal acquisition systems for motion analysis have led to lowcost and ubiquitous wearable sensors which can be used to record movement data in different settings. This implies the potential availability of large amounts of quantitative data. It is then crucial to identify and to extract the information of clinical relevance from the large amount of available data. This quantitative and objective information can be an important aid for clinical decision making. Data mining is the process of discovering such information in databases through data processing, selection of informative data, and identification of relevant patterns. The databases considered in this thesis store motion data from wearable sensors (specifically accelerometers) and clinical information (clinical data, scores, tests). The main goal of this thesis is to develop data mining tools which can provide quantitative information to the clinician in the field of movement disorders. This thesis will focus on motor impairment in Parkinson's disease (PD). Different databases related to Parkinson subjects in different stages of the disease were considered for this thesis. Each database is characterized by the data recorded during a specific motor task performed by different groups of subjects. The data mining techniques that were used in this thesis are feature selection (a technique which was used to find relevant information and to discard useless or redundant data), classification, clustering, and regression. The aims were to identify high risk subjects for PD, characterize the differences between early PD subjects and healthy ones, characterize PD subtypes and automatically assess the severity of symptoms in the home setting.

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Therapeutisches Drug Monitoring (TDM) umfasst die Messung von Medikamentenspiegeln im Blut und stellt die Ergebnisse in Zusammenhang mit dem klinischen Erscheinungsbild der Patienten. Dabei wird angenommen, dass die Konzentrationen im Blut besser mit der Wirkung korrelieren als die Dosis. Dies gilt auch für Antidepressiva. Voraussetzung für eine Therapiesteuerung durch TDM ist die Verfügbarkeit valider Messmethoden im Labor und die korrekte Anwendung des Verfahrens in der Klinik. Ziel dieser Arbeit war es, den Einsatz von TDM für die Depressionsbehandlung zu analysieren und zu verbessern. Im ersten Schritt wurde für das neu zugelassene Antidepressivum Duloxetin eine hochleistungsflüssig-chromatographische (HPLC) Methode mit Säulenschaltung und spektrophotometrischer Detektion etabliert und an Patienten für TDM angewandt. Durch Analyse von 280 Patientenproben wurde herausgefunden, dass Duloxetin-Konzentrationen von 60 bis 120 ng/ml mit gutem klinischen Ansprechen und einem geringen Risiko für Nebenwirkungen einhergingen. Bezüglich seines Interaktionspotentials erwies sich Duloxetin im Vergleich zu anderen Antidepressiva als schwacher Inhibitor des Cytochrom P450 (CYP) Isoenzyms 2D6. Es gab keinen Hinweis auf eine klinische Relevanz. Im zweiten Schritt sollte eine Methode entwickelt werden, mit der möglichst viele unterschiedliche Antidepressiva einschließlich deren Metaboliten messbar sind. Dazu wurde eine flüssigchromatographische Methode (HPLC) mit Ultraviolettspektroskopie (UV) entwickelt, mit der die quantitative Analyse von zehn antidepressiven und zusätzlich zwei antipsychotischen Substanzen innerhalb von 25 Minuten mit ausreichender Präzision und Richtigkeit (beide über 85%) und Sensitivität erlaubte. Durch Säulenschaltung war eine automatisierte Analyse von Blutplasma oder –serum möglich. Störende Matrixbestandteile konnten auf einer Vorsäule ohne vorherige Probenaufbereitung abgetrennt werden. Das kosten- und zeiteffektive Verfahren war eine deutliche Verbesserung für die Bewältigung von Proben im Laboralltag und damit für das TDM von Antidepressiva. Durch Analyse des klinischen Einsatzes von TDM wurden eine Reihe von Anwendungsfehlern identifiziert. Es wurde deshalb versucht, die klinische Anwendung des TDM von Antidepressiva durch die Umstellung von einer weitgehend händischen Dokumentation auf eine elektronische Bearbeitungsweise zu verbessern. Im Rahmen der Arbeit wurde untersucht, welchen Effekt man mit dieser Intervention erzielen konnte. Dazu wurde eine Labor-EDV eingeführt, mit der der Prozess vom Probeneingang bis zur Mitteilung der Messergebnisse auf die Stationen elektronisch erfolgte und die Anwendung von TDM vor und nach der Umstellung untersucht. Die Umstellung fand bei den behandelnden Ärzten gute Akzeptanz. Die Labor-EDV erlaubte eine kumulative Befundabfrage und eine Darstellung des Behandlungsverlaufs jedes einzelnen Patienten inklusive vorhergehender Klinikaufenthalte. Auf die Qualität der Anwendung von TDM hatte die Implementierung des Systems jedoch nur einen geringen Einfluss. Viele Anforderungen waren vor und nach der Einführung der EDV unverändert fehlerhaft, z.B. wurden häufig Messungen vor Erreichen des Steady State angefordert. Die Geschwindigkeit der Bearbeitung der Proben war im Vergleich zur vorher händischen Ausführung unverändert, ebenso die Qualität der Analysen bezüglich Richtigkeit und Präzision. Ausgesprochene Empfehlungen hinsichtlich der Dosierungsstrategie der angeforderten Substanzen wurden häufig nicht beachtet. Verkürzt wurde allerdings die mittlere Latenz, mit der eine Dosisanpassung nach Mitteilung des Laborbefundes erfolgte. Insgesamt ist es mit dieser Arbeit gelungen, einen Beitrag zur Verbesserung des Therapeutischen Drug Monitoring von Antidepressiva zu liefern. In der klinischen Anwendung sind allerdings Interventionen notwendig, um Anwendungsfehler beim TDM von Antidepressiva zu minimieren.

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There is an urgent need to improve the performance of urine cytology for the diagnosis of bladder cancer. In preliminary studies, telomerase activity evaluated by telomeric repeat amplification protocol (TRAP) assay and chromosomal aneuploidy detected by fluorescence in situ hybridization (FISH) in the diagnosis of bladder cancer have produced important results. Urine cell-free (UCF) DNA has also been proposed as a potential marker for early bladder cancer diagnosis. In the first study the diagnostic performance of TRAP assay and FISH analysis was assessed, while the second study evaluated the potential role of UCF DNA integrity in early bladder cancer diagnosis. In the first cross-sectional study, 289 consecutive patients who presented with urinary symptoms underwent cystoscopy and cytology evaluation. In the second study, UCF DNA was isolated from 51 bladder cancer patients, 46 symptomatic patients, and 32 healthy volunteers. c-Myc, BCAS1 and HER2 gene sequences longer than 250 bp were quantified by real time PCR to verify UCF DNA integrity. In the first study, sensitivity and specificity were 0.39 and 0.83, respectively, for cytology; 0.66 and 0.72 for TRAP; 0.78 and 0.60 for the cytology and TRAP combination; 0.78 and 0.78 for the cytology, TRAP and FISH combination; and 0.65 and 0.93 for the TRAP and FISH combination. In the second study, at the best cutoff of 0.1 ng/µl, UCF DNA integrity analysis showed a sensitivity of 0.73 and a specificity of 0.84 in healthy individuals and 0.83 in symptomatic patients. The preliminary results suggest that these biomarkers could potentially be used for the early diagnosis of bladder cancer, especially in high-risk populations (e.g, symptomatic individuals exposed to occupational risk) who may benefit from the use of noninvasive diagnostic tests in terms of cost-benefit.

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Nella presente tesi indaghiamo la potenzialità di LCM e Reverse Phase Protein microarray negli studi clinici. Si analizza la possibilità di creare una bio banca con line cellular primarie, al fine di conseguire drug test di sensibilità prima di decidere il trattamento da somministrare ai singoli pazienti. Sono stati ottenuti profili proteomici da biopsie pre e post terapia. I risultati dimostrano che questa piattaforma mostra il meccanismo di resistenza acquisito durante la terapia biologica. Questo ci ha portato ad analizzare una possibile stratificazione per pazienti con mCRC . I dati hanno rivelato distinti pathway di attivazione tra metastasi resecabile e non resecabili. I risultati mostrano inoltre due potenziali bersagli farmacologici. Ma la valutazione dell'intero tumore tramite singole biopsie sembra essere un problema a causa dell’eterogeneità intratumorale a livello genomico. Abbiamo indagato questo problema a livello dell'architettura del segnale in campioni di mCRC e ccRCC . I risultati indicano una somiglianza complessiva nei profili proteomici all'interno dello stesso tumore. Considerando che una singola biopsia è rappresentativa di un intera lesione , abbiamo studiato la possibilità di creare linee di cellule primarie, per valutare il profilo molecolare di ogni paziente. Fino ad oggi non c'era un protocollo per creare linee cellulari immortalizzate senza alcuna variazione genetica . abbiamo cosiderato, però, l'approccio innovativo delle CRCs. Ad oggi , non è ancora chiaro se tali cellule mimino il profilo dei tessuti oppure I passaggi in vitro modifichino i loro pathways . Sulla base di un modello di topo , i nostri dati mostrano un profilo di proteomica simile tra le linee di cellule e tessuti di topo LCM. In conclusione, i nostri dati dimostrano l'utilità della piattaforma LCM / RPPA nella sperimentazione clinica e la possibilità di creare una bio - banca di linee cellulari primarie, per migliorare la decisione del trattamento.

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Therapeutisches Drug Monitoring (TDM) findet Anwendung in der Therapie mit Immunosuppressiva, Antibiotika, antiretroviraler Medikation, Antikonvulsiva, Antidepressiva und auch Antipsychotika, um die Effizienz zu steigern und das Risiko von Intoxikationen zu reduzieren. Jedoch ist die Anwendung von TDM für Substanzen, die Einsatz finden in der Rückfallprophylaxe, der Substitution oder dem Entzug von Abhängigkeitserkrankungen nicht etabliert. Für diese Arbeit wurde im ersten Schritt eine sensitive Rating-Skala mit 22 Items entwickelt, mit Hilfe derer der theoretische Nutzen von TDM in der Pharmakotherapie von substanzbezogenen Abhängigkeitserkrankungen auf der Basis von pharmakologischen Eigenschaften der Medikamente und von Patientencharakteristika evaluiert wurde. Die vorgenommene Einschätzung zeigte für Bupropion, Buprenorphin, Disulfiram (oder einen Metaboliten), Methadon (chirale Bestimmung wenn möglich) und Naltrexon einen potentiellen Nutzen von TDM.rnFür die meisten Medikamente, die zur Behandlung von Abhängigkeitserkrankungen zugelassen sind, fehlen valide Messverfahren für TDM. Im Alltag werden überwiegend Drogen Screening-Tests in Form immunologischer Schnelltests angewendet. Für die Anwendung von TDM wurden in dieser Arbeit chromatographische Verfahren für die Bestimmung von Naltrexon und 6β-Naltrexol, Bupropion und Hydroxybupropion sowie R,S-Methadon und R,S-2-Ethyliden-1,5-dimethyl-3,3-diphenylpyrrolidin entwickelt, optimiert und validiert. Es handelt sich dabei HPLC-UV-Methoden mit Säulenschaltung sowie zur Bestimmung von Naltrexon und 6β-Naltrexol zusätzlich eine LC-MS/MS-Methode. Voraussetzung für die Interpretation der Plasmaspiegel ist im Wesentlichen die Kenntnis eines therapeutischen Bereichs. Für Naltrexon und seinen aktiven Metaboliten 6β-Naltrexol konnte eine signifikante Korrelation zwischen dem auftretenden Craving und der Summenkonzentration gefunden werden. Mittels Receiver-Operation-Characteristics-Kurven-Analyse wurde ein Schwellenwert von 16,6 ng/ml ermittelt, oberhalb dessen mit einem erhöhten Ansprechen gerechnet werden kann. Für Levomethadon wurde bezüglich der Detoxifikationsbehandlung ein Zusammenhang in der prozentualen Reduktion des Plasmaspiegels und den objektiven und subjektiven Entzugssymptomen gefunden. rnDoch nicht nur die Wirkstoffe, sondern auch das Patientenmerkmal substanzbezogene Abhängigkeit wurde charakterisiert, zum einen bezüglich pharmakokinetischer Besonderheiten, zum anderen in Hinsicht auf die Therapietreue (Adhärenz). Für Patienten mit komorbider Substanzabhängigkeit konnte eine verminderte Adhärenz unabhängig von der Hauptdiagnose gezeigt werden. Die Betrachtung des Einflusses von veränderten Leberwerten zeigt für komorbide Patienten eine hohe Korrelation mit dem Metabolisiererstatus, nicht aber für Patienten ohne Substanzabhängigkeit.rnÜbergeordnetes Ziel von TDM ist die Erhöhung der Therapiesicherheit und die Steigerung der Therapieeffizienz. Dies ist jedoch nur möglich, wenn TDM im klinischen Alltag integriert ist und korrekt eingesetzt wird. Obwohl es klare Evidenz für TDM von psychiatrischer Medikation gibt, ist die Diskrepanz zwischen Laborempfehlung und der klinischen Umsetzung hoch. Durch Intensivierung der interdisziplinären Zusammenarbeit zwischen Ärzten und Labor, der Entwicklung von interaktivem TDM (iTDM), konnte die Qualität der Anwendung von TDM verbessert und das Risiko von unerwünschten Arzneimittelwirkungen vermindert werden. rnInsgesamt konnte durch die eigenen Untersuchungen gezeigt werden, dass TDM für die medikamentöse Einstellung von Patienten mit Abhängigkeitserkrankung sinnvoll ist und dass optimales TDM eine interdisziplinäre Zusammenarbeit erfordert.rn

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The purpose of the first part of the research activity was to develop an aerobic cometabolic process in packed bed reactors (PBR) to treat real groundwater contaminated by trichloroethylene (TCE) and 1,1,2,2-tetrachloroethane (TeCA). In an initial screening conducted in batch bioreactors, different groundwater samples from 5 wells of the contaminated site were fed with 5 growth substrates. The work led to the selection of butane as the best growth substrate, and to the development and characterization from the site’s indigenous biomass of a suspended-cell consortium capable to degrade TCE with a 90 % mineralization of the organic chlorine. A kinetic study conducted in batch and continuous flow PBRs and led to the identification of the best carrier. A kinetic study of butane and TCE biodegradation indicated that the attached-cell consortium is characterized by a lower TCE specific degredation rates and by a lower level of mutual butane-TCE inhibition. A 31 L bioreactor was designed and set up for upscaling the experiment. The second part of the research focused on the biodegradation of 4 polymers, with and with-out chemical pre-treatments: linear low density polyethylene (LLDPE), polyethylene (PP), polystyrene (PS) and polyvinyl chloride (PVC). Initially, the 4 polymers were subjected to different chemical pre-treatments: ozonation and UV/ozonation, in gaseous and aqueous phase. It was found that, for LLDPE and PP, the coupling UV and ozone in gas phase is the most effective way to oxidize the polymers and to generate carbonyl groups on the polymer surface. In further tests, the effect of chemical pretreatment on polyner biodegrability was studied. Gas-phase ozonated and virgin polymers were incubated aerobically with: (a) a pure strain, (b) a mixed culture of bacteria; and (c) a fungal culture, together with saccharose as a co-substrate.

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BACKGROUND: The adequacy of thromboprophylaxis prescriptions in acutely ill hospitalized medical patients needs improvement. OBJECTIVE: To prospectively assess the efficacy of thromboprophylaxis adequacy of various clinical decision support systems (CDSS) with the aim of increasing the use of explicit criteria for thromboprophylaxis prescription in nine Swiss medical services. METHODS: We randomly assigned medical services to a pocket digital assistant program (PDA), pocket cards (PC) and no CDSS (controls). In centers using an electronic chart, an e-alert system (eAlerts) was developed. After 4 months, we compared post-CDSS with baseline thromboprophylaxis adequacy for the various CDSS and control groups. RESULTS: Overall, 1085 patients were included (395 controls, 196 PC, 168 PDA, 326 eAlerts), 651 pre- and 434 post-CDSS implementation: 472 (43.5%) presented a risk of VTE justifying thromboprophylaxis (31.8% pre, 61.1% post) and 556 (51.2%) received thromboprophylaxis (54.2% pre, 46.8% post). The overall adequacy (% patients with adequate prescription) of pre- and post-CDSS implementation was 56.2 and 50.7 for controls (P = 0.29), 67.3 and 45.3 for PC (P = 0.002), 66.0 and 64.9 for PDA (P = 0.99), 50.5 and 56.2 for eAlerts (P = 0.37), respectively, eAlerts limited overprescription (56% pre, 31% post, P = 0.01). CONCLUSION: While pocket cards and handhelds did not improve thromboprophylaxis adequacy, eAlerts had a modest effect, particularly on the reduction of overprescription. This effect only partially contributes to the improvement of patient safety and more work is needed towards institution-tailored tools.

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BACKGROUND: Chlorhexidine (CHX) rinsing after periodontal surgery is common. We assessed the clinical and microbiological effects of two CHX concentrations following periodontal surgery. MATERIALS AND METHODS: In a randomized, controlled clinical trial, 45 subjects were assigned to 4 weeks rinsing with a 0.05 CHX/herbal extract combination (test) or a 0.1% CHX solution. Clinical and staining effects were studied. Subgingival bacteria were assessed using the DNA-DNA checkerboard. Statistics included parametric and non-parametric tests (p<0001 to declare significance at 80% power). RESULTS: At weeks 4 and 12, more staining was found in the control group (p<0.05 and p<0.001, respectively). A higher risk for staining was found in the control group (crude OR: 2.3:1, 95% CI: 1.3 to 4.4, p<0.01). The absolute staining reduction in the test group was 21.1% (9 5% CI: 9.4-32.8%). Probing pocket depth (PPD) decreases were significant (p<0.001) in both groups and similar (p=0.92). No rinse group differences in changes of bacterial counts for any species were found between baseline and week 12. CONCLUSIONS: The test CHX rinse resulted in less tooth staining. At the study endpoint, similar and high counts of periodontal pathogens were found.

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BACKGROUND: Peri-implantitis is common in patients with dental implants. We performed a single-blinded longitudinal randomized study to assess the effects of mechanical debridement on the peri-implant microbiota in peri-implantitis lesions. MATERIALS AND METHODS: An expanded checkerboard DNA-DNA hybridization assay encompassing 79 different microorganisms was used to study bacterial counts before and during 6 months following mechanical treatment of peri-implantitis in 17 cases treated with curettes and 14 cases treated with an ultrasonic device. Statistics included non-parametric tests and GLM multivariate analysis with p<0001 indicating significance and 80% power. RESULTS: At selected implant test sites, the most prevalent bacteria were: Fusobacterium nucleatum sp., Staphylococci sp., Aggregatibacter actinomycetemcomitans, Helicobacter pylori, and Tannerella forsythia. 30 min. after treatment with curettes, A. actinomycetemcomitans (serotype a), Lactobacillus acidophilus, Streptococcus anginosus, and Veillonella parvula were found at lower counts (p<0.001). No such differences were found for implants treated with the ultrasonic device. Inconsistent changes occurred following the first week. No microbiological differences between baseline and 6-month samples were found for any species or between treatment study methods in peri-implantitis. CONCLUSIONS: Both methods failed to eliminate or reduce bacterial counts in peri-implantitis. No group differences were found in the ability to reduce the microbiota in peri-implantitis.

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Quantitative sensory tests are widely used in human research to evaluate the effect of analgesics and explore altered pain mechanisms, such as central sensitization. In order to apply these tests in clinical practice, knowledge of reference values is essential. The aim of this study was to determine the reference values of pain thresholds for mechanical and thermal stimuli, as well as withdrawal time for the cold pressor test in 300 pain-free subjects. Pain detection and pain tolerance thresholds to pressure, heat and cold were determined at three body sites: (1) lower back, (2) suprascapular region and (3) second toe (for pressure) or the lateral aspect of the leg (for heat and cold). The influences of gender, age, height, weight, body-mass index (BMI), body side of testing, depression, anxiety, catastrophizing and parameters of Short-Form 36 (SF-36) were analyzed by multiple regressions. Quantile regressions were performed to define the 5th, 10th and 25th percentiles as reference values for pain hypersensitivity and the 75th, 90th and 95th percentiles as reference values for pain hyposensitivity. Gender, age and/or the interaction of age with gender were the only variables that consistently affected the pain measures. Women were more pain sensitive than men. However, the influence of gender decreased with increasing age. In conclusion, normative values of parameters related to pressure, heat and cold pain stimuli were determined. Reference values have to be stratified by body region, gender and age. The determination of these reference values will now allow the clinical application of the tests for detecting abnormal pain reactions in individual patients.