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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.
591

Immunhistokemisk (IHC) analys av låggradigt inflammerade biopsier med apikal parodontit -en pilotstudie / Immunohistochemical (IHC) analysis of biopsies with apical periodontitis with assessed low-grade inflammation – a pilot study

Pesonen, Izabell, Ismail, Midia January 2021 (has links)
Syfte: Att ta reda på hur relationen ser ut för B- respektive T-lymfocyter i biopsier av rotfyllda tänder med apikal parodontit med bedömd låggradig inflammation. Denna studie kommer även att analysera hur den inflammatoriska bilden ser ut i förhållande till beskrivna symtom i dessa biopsier. Material & metod: En pilotstudie utfördes på 10 biopsier från rotfyllda tänder med apikal parodontit med bedömd låggradig inflammation enligt Danesh et al 2019 klassificeringssystem. Biopsierna hämtades från Malmö universitets biobank. Immunhistokemisk infärgning av antigenerna CD20+ och CD3+ utfördes samt analyserades med hjälp av digitalmikroskop. Jämförelsen av symtomen från remisserna skedde efter att de histologiska resultaten sammanställts. Resultat: Det fanns fler T-lymfocyter än B-lymfocyter i 6 stycken av biopsierna. I de resterande 4 biopsierna var de lika många. I remisserna hade symtombilden inte angetts föralla biopsier. Slutsats: Enligt vår pilotstudie ser vi tendenser till att T-lymfocyter är fler än B-lymfocyter eller att de är lika många. Inga slutsatser kunde dras gällande symtombilden. Ett större material från olika remittenter krävs för definitiva slutsatser. En vidare infärgning av CD4+ samt CD8+ skulle vara intressant. / Aim: To investigate the relation between B- and T- lymphocytes in biopsies of root-filled teeth with apical periodontitis with assessed low-grade inflammation. This study will also analyse what the inflammation looks like in relation to the symptoms described in these biopsies.  Study design: A pilot study was performed on 10 biopsies of root-filled teeth with apical periodontitis with assessed low-grade inflammation according to the classification system of Danesh et al 2019. The biopsies were collected from Malmö University's biobank. An immunohistochemical staining of antigens CD20+ and CD3+ were performed and analysed by a digital microscope. A comparison of the symptoms from the referrals were performed once the histological results were compiled. Results: There were more T-lymphocytes than B-lymphocytes in 6 of the biopsies. In the remaining 4 biopsies there were an equal amount of B- and T-lymphocytes. The symptoms were not stated for all biopsies in the referrals.  Conclusion: According to our pilot study, we see tendencies that T lymphocytes are more than B lymphocytes or that they are equal. No conclusions could be drawn regarding the symptom picture. Larger material from different referrers is required for definitive conclusions. A further staining of CD4 + and CD8 + would be interesting.
592

Sensitive Quantification of Cell-Free Tumor DNA for Early Detection of Recurrence in Colorectal Cancer

Stasik, Sebastian, Mende, Marika, Schuster, Caroline, Mahler, Sandra, Aust, Daniela, Tannapfel, Andrea, Reinacher-Schick, Anke, Baretton, Gustavo, Krippendorf, Claudia, Bornhäuser, Martin, Ehninger, Gerhard, Folprecht, Gunnar, Thiede, Christian 08 April 2024 (has links)
The detection of plasma cell–free tumor DNA (ctDNA) is prognostic in colorectal cancer (CRC) and has potential for early prediction of disease recurrence. In clinical routine, ctDNA-based diagnostics are limited by the low concentration of ctDNA and error rates of standard next-generation sequencing (NGS) approaches. We evaluated the potential to increase the stability and yield of plasma cell–free DNA (cfDNA) for routine diagnostic purposes using different blood collection tubes and various manual or automated cfDNA extraction protocols. Sensitivity for low-level ctDNA was measured in KRAS-mutant cfDNA using an error-reduced NGS procedure. To test the applicability of rapid evaluation of ctDNA persistence in clinical routine, we prospectively analyzed postoperative samples of 67 CRC (stage II) patients. ctDNA detection was linear between 0.0045 and 45%, with high sensitivity (94%) and specificity (100%) for mutations at 0.1% VAF. The stability and yield of cfDNA were superior when using Streck BCT tubes and a protocol by Zymo Research. Sensitivity for ctDNA increased 1.5-fold by the integration of variant reads from triplicate PCRs and with PCR template concentration. In clinical samples, ctDNA persistence was found in ∼9% of samples, drawn 2 weeks after surgery. Moreover, in a retrospective analysis of 14 CRC patients with relapse during adjuvant therapy, we successfully detected ctDNA (median 0.38% VAF; range 0.18–5.04% VAF) in 92.85% of patients significantly prior (median 112 days) to imaging-based surveillance. Using optimized pre-analytical conditions, the detection of postoperative ctDNA is feasible with excellent sensitivity and allows the prediction of CRC recurrence in routine oncology testing.
593

Novel Diagnostic and Prognostic Methods for Cancer and Cancer Associated Thrombosis

Oto Martínez, Ana Julia 02 August 2023 (has links)
Tesis por compendio / [ES] El cáncer constituye la segunda causa de muerte en España. El tromboembolismo venoso (TEV), una complicación del cáncer, conlleva gran gasto del presupuesto sanitario y representa la segunda causa de muerte en estos pacientes. Sin embargo, las herramientas actuales disponibles para la identificación de pacientes oncológicos con elevado riesgo trombótico son limitadas. Adicionalmente, no existen métodos simples, mínimamente invasivos y económicos de diagnóstico de cáncer vesical. Por este motivo, se utilizan técnicas dañinas como la tomografía computarizada la cual implica una elevada dosis de exposición a radiación y procedimientos invasivos como la cistoscopia. Además, un estado hipercoagulable parece tener una relación directa con una mayor carga tumoral y un peor pronóstico. El objetivo principal de la presente Tesis Doctoral es explorar la utilidad clínica de nuevos métodos diagnósticos y pronósticos para el cáncer y sus complicaciones trombóticas. En la primera parte de la Tesis, nos hemos centrado en el papel de miRNAs en orina como biomarcadores de cáncer vesical. Hemos identificado al miR-29c-3p como el miRNA más estable por lo que fue utilizado como normalizador. Hemos ajustado un modelo de regresión logística ordinal para el diagnóstico y estratificación de cáncer vesical utilizando la expresión de miRNAs en orina de pacientes y controles. Este modelo incluyó la expresión de 7 miRNAs: miR-221-3p, miR-93-5p, miR-362-3p, miR-191-5p, miR-200c-3p, miR-192-5p y miR-21-5p. En la segunda parte de la Tesis, nos centramos en el estudio de nuevos biomarcadores para la trombosis asociada a cáncer. Analizamos el potencial predictivo de los miRNAs y de marcadores de activación de neutrófilos en pacientes con cáncer pancreático y pacientes con glioma y meningioma. En cáncer pancreático, obtuvimos un perfil de 7 miRNAs (miR-486-5p, miR-106b-5p, let-7i-5p, let-7g-5p, miR-144-3p, miR-19a-3p y miR-103a-3p) capaz de estimar el riesgo de TEV al diagnóstico con dianas incluidas en las rutas pancreatic cancer y complement and coagulation cascades. En el estudio de los marcadores de activación de neutrófilos, obtuvimos un nuevo modelo predictivo de TEV con la calprotectina como variable predictora. Respecto al estudio de trombosis asociada a cáncer en tumores intracraneales, en pacientes con glioma, ajustamos y validamos un modelo predictivo de embolismo pulmonar (EP) postquirúrgico con 6 miRNAs: miR-363-3p, miR-93-3p, miR-22-5p, miR-451a, miR-222-3p y miR-140-3p y otro con cfDNA y mieloperoxidasa como predictores. Además, hemos combinado los dos tipos de marcadores y hemos obtenido un modelo con mayor capacidad predictiva que incluye a miR-140-3p y a la mieloperoxidasa como predictores. En pacientes con meningioma, ajustamos y validamos un modelo predictivo de EP postquirúrgico con 6 miRNAs: miR-29a-3p, miR-660-5p, miR-331-3p, miR-126-5p, miR-23a-3p y miR-23b-3p. En conclusión, proponemos diferentes perfiles de biomarcadores para el diagnóstico de cáncer de vejiga y para la identificación de pacientes oncológicos con elevado riesgo de trombosis. / [CA] El càncer constitueix la segona causa de mort a Espanya. El tromboembolisme venós (TEV), una complicació del càncer, representa la segona causa de mort en aquests pacients i comporta una gran despesa sanitària. No obstant això, les eines disponibles actualment per a la identificació de pacients oncològics amb elevat risc trombòtic són limitades. Actualment, no existeixen mètodes diagnòstics per al càncer de bufeta senzills, mínimament invasius i econòmics. Per aquest motiu, s'utilitzen tècniques nocives com la tomografia computada la qual implica una elevada dosi d'exposició a radiació i procediments invasius com la cistoscòpia. A més, un estat hipercoagulable sembla tindre una relació directa amb una major càrrega tumoral i un pitjor pronòstic. L'objectiu principal de la present Tesi Doctoral fou explorar la utilitat clínica de nous mètodes diagnòstics i pronòstics per al càncer i les seues complicacions trombòtiques. En la primera part de la Tesi, ens hem centrat en el paper dels microRNAs (miRNAs) en orina com biomarcadors de càncer de bufeta. Hem identificat al miR-29c-3p com el miRNA més estable per la qual cosa va ser utilitzat com a normalitzador. Hem ajustat un model de regressió logística ordinal per al diagnòstic i estratificació de càncer de bufeta utilitzant l'expressió de miRNAs en orina de pacients i controls. Aquest model va incloure l'expressió de 7 miRNAs: miR-221-3p, miR-93-5p, miR-362-3p, miR-191-5p, miR-200c-3p, miR-192-5p i miR-21-5p. En la segona part de la Tesi, ens centràrem en l'estudi de nous biomarcadors per a la trombosi associada a càncer. Analitzàrem el potencial predictiu dels miRNAs i de marcadors d'activació de neutròfils en pacients amb càncer pancreàtic i pacients amb glioma i meningioma. En càncer pancreàtic, vàrem obtindre un perfil de 7 miRNAs (miR-486-5p, miR-106b-5p, let-7i-5p, let-7g-5p, miR-144-3p, miR-19a-3p i miR-103a-3p) capaç d'estimar el risc de TEV al diagnostic dels pacients els quals tenen dianes incloses en les rutes biològiques pancreatic cancer y complement and coagulation cascades. En el estudi dels marcadors d¿activació de neutròfils, vàrem obtenir un altre model predictiu de TEV amb la calprotectina com a variable predictora. Respecte a l'estudi de trombosi associada a càncer en tumors intracranials, en pacients amb glioma, ajustàrem i validàrem un model predictiu d'embolisme pulmonar (EP) incidental postquirúrgic amb 6 miRNAs (miR-363-3p, miR-93-3p, miR-22-5p, miR-451a, miR-222-3p i miR-140-3p) i un altre amb cfDNA i mieloperoxidasa com a predictors. A més, vàrem combinar els dos tipus de marcadors i vàrem obtenir un model amb major capacitat predictiva que inclou al miR-140-3p i la mieloperoxidasa com a predictors. En pacients amb meningioma, ajustàrem i validàrem un model predictiu d¿EP incidental postquirúrgic amb 6 miRNAs: miR-29a-3p, miR-660-5p, miR-331-3p, miR-126-5p, miR-23a-3p i miR-23b-3p. En conclusió, proposem diferents perfils de biomarcadors per al diagnòstic de càncer de bufeta i per a la identificació de pacients oncològics amb elevat risc de trombosi. / [EN] Cancer is the second leading cause of death in Spain. Collaterally, venous thromboembolism (VTE), as a complication of cancer, consumes a great part of its healthcare budget and, more importantly, it is the second cause of death in these patients. However, limited tools are available to identify high risk patients. Additionally, a simple, minimally invasive and economical diagnostic methods for bladder cancer are also lacking. For that aim, harmful techniques are used like CT scan with high radiation exposure and invasive procedures like cystoscopy. Moreover, a hypercoagulable state seems directly related to a large tumor burden and poor prognosis. The overall aim of this Doctoral Thesis is to explore the clinical utility of novel diagnostic and prognostic methods for cancer and its thrombotic complications. In the first part of this Doctoral Thesis, we focused on the role of urine miRNAs as bladder cancer biomarkers. We identified miR-29c-3p as the most stable miRNA and was therefore used as normalizer. We adjusted an ordinal logistic regression model for the diagnosis and stratification of BC using the urine miRNA expression levels of patients and controls. This model included 7 miRNAs: miR-221-3p, miR-93-5p, miR-362-3p, miR-191-5p, miR-200c-3p, miR-192-5p and miR-21-5p. In the second part of this Doctoral Thesis, we focused on the study of novel biomarkers for cancer-associated thrombosis. We analyzed the predictive potential of miRNAs and neutrophil activation markers of thrombotic events in patients with pancreatic cancer and patients with glioma and meningioma. In pancreatic cancer, we obtained a profile of 7 miRNAs (miR-486-5p, miR-106b-5p, let-7i-5p, let-7g-5p, miR-144-3p, miR-19a-3p and miR-103a-3p) able to estimate the risk of potential VTE at diagnosis with targets involved in the pancreatic cancer and complement and coagulation cascades pathways. In the study of the neutrophil activation makers, we obtained a new predictive model of VTE with calprotectin as predictor. Regarding the study of cancer-associated thrombosis in intracranial tumors, in glioma patients, we adjusted and validated a predictive model for post-surgical pulmonary embolism (PE) with 6 miRNAs: miR-363-3p, miR-93-3p, miR-22-5p, miR-451a, miR-222-3p and miR-140-3p, and another with cfDNA and myeloperoxidase as predictors. Furthermore, we combined both types of biomarkers and obtained an improved model using myeloperoxidase and miR-140-3p as predictors. In meningioma patients we fitted and validated a predictive model with 6 miRNAs: miR-29a-3p, miR-660-5p, miR-331-3p, miR-126-5p, miR-23a-3p and miR-23b-3p. In conclusion, we propose several profiles of biomarkers for the diagnosis of bladder cancer and for the identification of oncologic patients at high risk of suffering a thrombotic event. / Oto Martínez, AJ. (2022). Novel Diagnostic and Prognostic Methods for Cancer and Cancer Associated Thrombosis [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/181510 / Compendio
594

Non-Invasive Immunogram. A Multidimensional Approach to Characterize and Monitor Immune Status in Non-Small Cell Lung Cancer

Moreno Manuel, Andrea 22 April 2025 (has links)
[ES] El cáncer de pulmón no microcítico (CPNM) representa un 80% de los casos de cáncer de pulmón, siendo uno de los tipos de cáncer más frecuentes y mortales. El tratamiento con inmunoterapia ha mejorado significativamente el pronóstico de los pacientes en las últimas décadas. No obstante, no todos los pacientes responden al tratamiento, por lo que se necesitan nuevos biomarcadores para predecir qué pacientes se podrían beneficiar de la inmunoterapia. El principal objetivo de esta tesis es obtener nuevos biomarcadores no invasivos para pacientes de CPNM avanzado tratados con inmunoterapia. Se incluyeron 52 pacientes de CPNM en estadios avanzados tratados con anti-PD1 o anti-PD1 en combinación con quimioterapia (anti-PD1+CT) en primera línea. Se analizaron biomarcadores no invasivos en muestras de sangre periférica, obtenidas antes del tratamiento y en la primera evaluación de respuesta. Los biomarcadores analizados en este estudio fueron: i) parámetros hematológicos e inmunológicos, ii) expresión de genes inmunoreguladores en células mononucleares de sangre periférica (PBMCs), iii) repertorio de TCR-ß y iv) genotipo de HLA. También se analizaron 13 controles sanos, y se observó que los pacientes con CPNM presentaron menores niveles de expresión de genes relacionados con las células T. Además, los pacientes con CPNM tenían menor número de clones de TCR-ß. Se analizó el valor predictivo y pronóstico de los potenciales biomarcadores independientemente en pacientes tratados con anti-PD1 o anti-PD+CT. Se encontraron biomarcadores con valor pronóstico, bien en las muestras basales o en las muestras tomadas en la primera evaluación de respuesta. Al utilizar muestras no invasivas, también se pudo estudiar la dinámica de los biomarcadores a lo largo del tratamiento, observando que algunos cambios ocurrían de manera diferencial en pacientes respondedores o dependiendo del tratamiento. La integración de los datos de las variables analizadas ha resultado en una propuesta de un modelo multivariante capaz de predecir qué pacientes tendrán mejor pronóstico, en el subgrupo de pacientes tratados con anti-PD1. Además, se crearon dos inmunogramas no invasivos incluyendo los ratios de los biomarcadores entre muestras tomadas antes y durante el tratamiento. Estos modelos se realizaron específicamente para cada tipo de tratamiento, y podrían ser útiles para monitorizar la respuesta durante el tratamiento. Este estudio resalta el papel de la biopsia líquida como una herramienta no invasiva para analizar biomarcadores de forma integral que permiten caracterizar y monitorizar el estatus inmune en pacientes con CPNM tratados con inmunoterapia o quimioinmunoterapia. / [CA] El càncer de pulmó no microcític (CPNM) representa un 80% dels casos de càncer de pulmó, i és un dels tipus de càncer més freqüents i mortals. El tractament amb immunoteràpia ha millorat significativament el pronòstic dels pacients en les últimes dècades. Malgrat això, no tots el pacients responen, per la qual cosa es necessiten nous biomarcadors per predir què pacients es beneficiaran del tractament amb immunoteràpia. El principal objectiu d'aquesta tesi és obtindre nous biomarcadors no invasius per a pacients de CPNM avançat tractats amb immunoteràpia. Es van incloure 52 pacients de CPNM en estadis avançats tractats amb anti-PD1 o anti-PD1 en combinació amb quimioteràpia (anti-PD1+CT) en primera línia. Es van analitzar biomarcadors no invasius a partir de mostres de sang perifèrica, que es van obtindre abans del tractament i en la primera avaluació de resposta. Els potencials biomarcadors analitzats en aquest estudi van ser: i) paràmetres hematològics i immunològics, ii) expressió de gens immunoreguladors en cèl·lules mononuclears de sang perifèrica (PBMCs), iii) repertori de TCR-ß i iv) genotip d'HLA. També es van analitzar 13 controls sans, i es va observar que els pacients amb CPNM presentaven menors nivells d'expressió de gens relacionats amb les cèl·lules T. A més, els pacients amb CPNM tenien menor riquesa de repertori de TCR-ß. S'han analitzat el valor predictiu i pronòstic dels potencials biomarcadors independentment en pacients tractats amb anti-PD1 o anti-PD1+CT. S'han trobat biomarcadors amb valor pronòstic, bé en les mostres basals o en les mostres preses en la primera avaluació de resposta. Com s'han utilitzat mostres no invasives, també s'ha pogut analitzar la dinàmica dels biomarcadores al llarg del tractament, i s'han observat canvis específics de pacients responedors o del tipus de tractament. La integració de les variables analitzades ha resultat en una proposta d'un model multivariant capaç de predir quins pacients amb CPNM tindran millor pronòstic, en el subgrup de pacients tractats amb anti-PD1. També s'han fet dos immunograms no invasius incloent els ràtios dels biomarcadors entre mostres preses abans i durant el tractament. Aquests models son específics per a cada tipus de tractament, i podrien ser útils per a monitorar la resposta durant el tractament. Aquest estudi ressalta el paper de la biòpsia líquida com una eina no invasiva per a analitzar biomarcadors de forma integral que permeten caracteritzar i monitorar l'estatus immune en pacients amb CPNM tractats amb immunoteràpia o quimioimmunoteràpia. / [EN] Non-Small Cell Lung Cancer (NSCLC) represents 80% of lung cancer cases, being one of the most frequent and death causing cancers. Recently developed treatments with immunotherapy have improved patient prognosis. However, a significant number of patients do not respond to treatment, thus there is an urgent need for biomarkers to predict which patients will benefit from immunotherapy. The main objective of this thesis was to obtain novel non-invasive biomarkers for advanced-stage NSCLC patients treated with immunotherapy. This study included 52 advanced-stage NSCLC patients treated with Anti-PD1 or Anti-PD1 in combination with chemotherapy (Anti-PD1+CT) in the first line setting. Non-invasive biomarkers were analysed using peripheral blood samples, which were obtained before first cycle and at first response assessment. The potential biomarkers analysed in this study were: i) haematological and immunological parameters, ii) immune-related gene expression analysed on Peripheral Blood Mononuclear Cells (PBMCs), iii) TCR-ß repertoire, and iv) HLA genotype. 13 healthy subjects were also included in this study. NSCLC patients presented lower T cell related gene expression levels than controls. Furthermore, cancer patients had a lower number of unique TCR-ß clones. We have assessed the predictive and prognostic value of the analysed variables independently on patients treated with anti-PD1 or anti-PD1+CT. We found prognostic biomarkers that could be useful to identify patients who benefit from treatment. Since we used non-invasive samples, we also observed differences in immune-related biomarkers at first response assessment in patients responding to treatment. In addition, biomarker dynamics were useful to identify changes occurring throughout treatment. The integration of data from the analysed variables has resulted in a proposal of a multivariate model capable of predicting patients with improved outcomes to treatment with anti PD1 therapy. Moreover, we have developed two non-invasive inmunograms including the ratios of on- and pre-treatment samples, which could be useful to monitor patients throughout treatment. Altogether, this study highlights the role of non-invasive biomarkers to characterize and monitor immune status in NSCLC patients treated with immunotherapy or chemoimmunotherapy. / This Thesis was supported by the following grants: Fundación Científica Asociación Española Contra el Cáncer. PRDVA18015MORE; Centro de Investigación Biomédica en Red Cáncer. Project B16/12/00350 e Instituto de Salud Carlos III: PI18/00266 / Moreno Manuel, A. (2024). Non-Invasive Immunogram. A Multidimensional Approach to Characterize and Monitor Immune Status in Non-Small Cell Lung Cancer [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/204490
595

Entwicklung einer spulenintegrierten und automatisch gesteuerten Biopsieeinrichtung zur histologischen Abklärung von Kleintumoren in der MR-Mammadiagnostik

Wendt, Oliver 27 July 2004 (has links)
Brustkrebs stellt eine der am häufigsten vorkommenden Krebserkrankungen bei Frauen weltweit dar. Jährlich erkranken in Deutschland ca. 47.000 Frauen neu an Brustkrebs, ca. 18.000 fallen dieser Krankheit im gleichen Zeitraum zum Opfer. Die Brustkrebsdiagnostik basiert auf klinische und verschiedene bildgebende Methoden, die Magnetresonanztomographie (MRT) weist dabei die höchste Sensitivität speziell bei der Erkennung kleiner Tumore unter 5 mm auf. Im Hinblick auf zukünftige Verbesserungen der MR-Bildgebung wird bereits vermutet, dass im Jahr 2010 ca. 50% der neudetektierten Brustkrebse kleiner als 10 mm sein werden. Zur Erhöhung der Diagnosesicherheit werden suspekte Läsionen sowie unklare bildgestützte Befunde zusätzlich mittels Biopsie abgeklärt. In Bezug auf den Stand der Technik ist die sichere Biopsie von Tumoren unter 10 mm Größe jedoch schwierig. Mit dem Ziel, die MR-gestützte Biopsie im Hinblick auf eine höhere Effizienz und Präzision zu verbessern, wurde ein neuer Prototyp für minimal invasive Biopsien speziell in geschlossenen MR-Tomographen entwickelt. Dieses MR-kompatible System basiert auf verschiedene Neukonzeptionen, mit einem automatischen Positioniersystem und Biopsieinstrument zur Ausführung der Intervention. Die extrem hohen Anforderungen an dieses System konnten nur durch spezielle Konstruktionen und Kinematiken, sowie durch MR-kompatible Materialien, Aktoren und Sensoren gelöst werden. Das System ist modular aufgebaut und unterstützt Brustbiopsien sowohl von cranial oder caudal im direkten Anschluss an die Tumorerkennung mit einer neuen doppelseitigen MR-Brustspule. Ein großer Vorteil dieses neuen Ansatzes liegt in der hohen Präzision und der Möglichkeit, sowohl die bildgebende Diagnostik als auch die Biopsie während eines Untersuchungstermines durchzuführen. Die vorklinische Erprobung in einem 1,5 T Hochfeld-MRT zeigte, dass die Zielabweichungen des Instrumentes geringer als 1 mm waren, so dass Interventionen mit hoher Genauigkeit und Reproduzierbarkeit durchführbar wären. Das System implementiert benutzerfreundliche Oberflächen für die Interventionsplanung und für die Gerätesteuerung. Das vorliegende Dissertation stellt die Konzepte und Ergebnisse dieser neuen Biopsieeinrichtung vor und nimmt Bezug auf zahlreiche wissenschaftliche Untersuchungen, insbesondere im Hinblick auf die Anwendung von Materialien und Aktoren im MRT-Magnetfeld. / Breast cancer is one of the most common cancer diseases which women suffer world wide. The incidence rate of breast cancer in Germany goes along with about 47.000 women per year, 18.000 fatal casualties were ascertained in the same period. The breast cancer diagnostic is based on clinical and different imaging methods, whereas Magnetic Resonance Imaging (MRI) is the most sensitive imaging modality in the detection of especially small lesions under 5 mm. Due to improvements of breast imaging - especially MRI - it has been predicted that by the year 2010 about 50% of newly diagnosed breast cancers will be less than 10 mm in size. However, to assure the image based breast cancer diagnosis, biopsies of tumor tissue are often necessary in order to avoid false specified results. With reference to the state of the art, it is still difficult to achieve sufficient accurate MRI-supported biopsies for tumor sizes of under 10 mm. To improve the MR-controlled diagnostic in respect of increasing the efficiency and precision of the biopsy method, a new apparatus for minimal invasive breast biopsies particularly for the use inside closed bore MRI-scanner was developed. This MR-compatible device is based on new concepts which meet the extremely high requirements on interventions in strong magnetic fields through special designs and kinematic concepts and the application of MR-compatible materials, actors and sensor systems. It is of a modular structure and consists mainly of an automated positioning unit and an integrated intervention tool. This new system makes it possible to do the breast interventions either from the cranial or the caudal position directly after tumor detecting with the use of a new double breast coil. A major advantage of this approach is the high accuracy and the possibility to realize image diagnostic and biopsy in one session. As the preclinical evaluation with a 1.5 T MRI-scanner showed, the deviation of the intervention device regarding instrument positioning to a located target was less than 1mm, so that interventions could be carried out precisely and reproducible. Furthermore there were no image interferences due to the additional materials in the MRI-isocenter. The system implements a user-interface for intervention planning on up-to-date MR images and device control. Besides the concepts and results of the new biopsy device, the present dissertation refers to numerous scientific investigations with a focus on material and actuator application in the magnetic field of a MRI-scanner.
596

"Avaliação imunohistoquímica das células inflamatórias presentes na parede de artérias pulmonares periféricas de pacientes com doença vaso-oclusiva pulmonar secundária a defeitos cardíacos congênitos" / Immunohystochemical evaluation of inflammatory cells in the walls of peripheral pulmonary arteries from patients with pulmonary vasoclusive disease secondary to cardiac congenital defects

Pinto, Rubens Fraga Alves 11 August 2004 (has links)
Para avaliar a hipótese da presença de inflamação em artérias pulmonares periféricas de pacientes com hipertensão pulmonar (HP) decorrente de cardiopatias congênitas, foram quantificadas células inflamatórias através de marcação imunohistoquímica em biópsias de 26 pacientes e comparadas com 11 controles sem cardiopatia. Detectou-se quantidades semelhantes de células inflamatórias nos dois grupos, mas com predomínio de linfócitos T no grupo controle e de macrófagos jovens no grupo HP. Esses achados podem estar relacionados com a redução do estímulo dependente de macrófagos para diferenciação e maturação de linfócitos T nos cardiopatas e/ou a deficiência imunológica primária nesses pacientes / To evaluate the hypothesis of increased inflammation in peripheral pulmonary arteries from patients with pulmonary hypertension secondary to congenital cardiac shunts, we quantified the inflammatory cells with the aid of immunohystochemistry in 26 biopsies (HP group), comparing them to 11 patients with no cardiac disease. Similar quantities of inflammatory cells were observed in the two groups, with a predominance of T-lymphocytes in the controls and of young macrophages in the HP group. These findings could be related to a reduction of macrophagic stimulus to the differentiation and maturation of T-lymphocytes and/or to a primary immunological deficiency in patients with congenital cardiac shunts
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Avaliação da musculatura estriada de membros inferiores na limitação funcional ao exercício em pacientes com hipertensão arterial pulmonar / Assessment of skeletal muscle of lower limb in functional exercise limitation in patients with pulmonary arterial hypertension

Breda, Ana Paula 25 April 2011 (has links)
Introdução: A hipertensão arterial pulmonar (HAP) é uma doença progressiva extremamente grave, que evolui com insuficiência cardíaca direita e morte. Apesar do avanço do tratamento farmacológico, o prognóstico permanece reservado com taxa de sobrevida de 86%, 70% e 55% em 1, 3 e 5 anos, respectivamente. A dispnéia progressiva e a intolerância ao exercício são as principais manifestações clínicas e refletem a falência do ventrículo direito. O músculo esquelético periférico parece ser também um dos principais determinantes desta limitação funcional, visto que a redução da oferta de oxigênio e alterações na extração/utilização do oxigênio pelo músculo são diretamente relacionados com a tolerância ao exercício. Existem dois mecanismos potencialmente envolvidos na regulação da oferta de oxigênio, e portanto, na capacidade de exercício: mecanismos centrais (função do coração, pulmão e sistema nervoso autônomo) e mecanismos periféricos (associado ao fluxo sanguíneo periférico e a função do músculo esquelético). Os pacientes com HAP geralmente apresentam baixo débito cardíaco e estado adrenérgico exacerbado. A combinação destas alterações pode resultar em alterações estruturais e funcionais da musculatura estriada periférica. Porém, não existem informações sólidas que nos esclareçam se o acometimento muscular é preditor independente da limitação da capacidade de exercício. Objetivos: (1) Caracterizar o papel da musculatura periférica na limitação funcional em pacientes com HAP. (2) Avaliar o papel do sistema muscular periférico como um fator independente para a limitação ao exercício em HAP. Materiais e métodos: Dezesseis pacientes com HAP foram prospectivamente comparados com 10 indivíduos controle em termos de dados demográficos, qualidade de vida relacionada à saúde e limitação ao exercício, avaliada pelo teste de caminhada de seis minutos, teste cardiopulmonar, dinamometria isocinética e medições de pressão respiratória máxima. Pacientes com HAP também foram submetidos à biópsia do quadríceps, a fim de avaliar as mudanças estruturais. Resultados: Os pacientes com HAP apresentaram pior qualidade de vida (componente físico p<0,001), menor percentagem de massa magra (p=0,044), menor força muscular respiratória (p<0,001), menor resistência e força dos extensores de coxa (p=0,017 e p=0,012, respectivamente) e maior limitação funcional demonstrada pela distância percorrida no teste de caminhada de seis minutos (p<0,001) e pelo teste de exercício cardiopulmonar (p<0,001 para VO2/kg), em comparação ao grupo controle. Estes achados de redução de força e função muscular estão em acordo com os achados de redução da percentagem de fibras do Tipo I à biópsia muscular. O consumo de oxigênio, apresentou correlação com a função da musculatura respiratória e da musculatura extensora de coxa (resistência e força), e com a proporção de fibras oxidativas (Tipo I). O débito cardíaco também apresentou correlação com o VO2. o modelo de análise bivariada demonstrou que a função muscular é preditora independente do VO2 pico, mesmo com a correção para o perfil hemodinâmico. Conclusão: (1) Pacientes com HAP apresentam alteração estrutural e funcional da musculatura estriada periférica, e (2) estas alterações determinam limitação da capacidade global de exercício de forma independente do padrão hemodinâmico característico da HAP / Introduction: Pulmonary arterial hypertension (PAH) is a relentlessly progressive disease that leads to right heart failure and death. Despite advances in pharmacological treatment, prognosis is still poor with survival rates of 86%, 70% and 55% at 1, 3 and 5 years, respectively. Progressive dyspnea and exercise intolerance are the main clinical manifestations and reflect the impairment of right ventricular function. Peripheral skeletal muscle also seems to be a major determinant of functional limitation, as the reduction of oxygen supply and changes in extraction and utilization of oxygen by the muscle are directly associated to exercise tolerance. There are two potential mechanisms involved in the regulation of oxygen supply and therefore in exercise capacity: central (as a function of heart, lung and autonomic nervous system function) and peripheral (associated to peripheral blood flow and skeletal muscle function). Patients with PAH usually present low cardiac output and exacerbated adrenergic state. The combination of these features might result in changes of peripheral skeletal muscle and structure. However, there is no robust information that clearly clarifies whether the muscle involvement is an independent factor for exercise limitation. Objectives: (1) Characterize the role of the peripheral muscles in functional limitation in patients with PAH. (2) Address the role of the peripheral muscle system as an independent factor in exercise limitation in PAH. Materials and methods: Sixteen PAH patients were prospectively compared to 10 control individuals in terms of demographic data, health related quality of life and exercise limitation, assessed by six-minute walk test, cardiopulmonary test, isokinetic dynamometry and maximum respiratory pressure measurements. PAH patients also were submitted to vastus lateralis biopsy in order to assess structural changes. Results: PAH patients presented poorer quality of life (p <0.001), lower percentage of fat free mass (p = 0.044), lower respiratory muscle strength (p <0.001), lower resistance and strength of the extensor of the thigh (p = 0.017 and 0.012, respectively) and greater functional limitation demonstrated by the six-minute walk distance (p <0.001) and at the cardiopulmonary exercise test (p <0.001 for VO2max/kg), as compared to the control group. These findings of reduced muscle strength and function are in agreement with the findings of reduced percentage of Type I fibers at the muscle biopsy. The oxygen consumption correlated to the function of respiratory muscles and of extensor muscles of the thigh (endurance and strength) as well as to the proportion of oxidative fibers (Type I). The cardiac output also correlated with VO2. A bivariate model demonstrated that muscle function is an independent predictor of maximum oxygen consumption, even correcting for the hemodynamic profile. Conclusion: (1) PAH patients present functional and structural changes in peripheral skeletal muscles, and (2) these changes determine overall exercise capacity limitation, independently of the hemodynamic pattern
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O papel do acúmulo do colágeno miocárdico intersticial na sobrevida dos pacientes com miocardiopatia dilatada idiopática e chagásica / The role of myocardial interstitial collagen in the survival rate of patients with idiopathic and chagasic cardiomyopathy.

Nunes, Vera Lopes 29 July 2004 (has links)
As miocardiopatias dilatadas representam 87% das miocardiopatias e apresentam evolução adversa com grande morbi-mortalidade. Vários marcadores de prognóstico são bem definidos, entretanto, um marcador estrutural se faz necessário. Estudamos através da realização da biópsia endomiocárdica e exame ecocardiográfico, 9 indivíduos sem doença estrutural miocárdica (controle) e 45 pacientes com miocardiopatia dilatada grave de etiologia idiopática (MCDI) e chagásica (MCDC). Observamos se havia relação entre a quantidade de colágeno miocárdico intersticial (FVCI) e a sobrevida destes pacientes, se a FVCI diferia entre as etiologias, e se a fibrose interferia na função e geometria do miocárdio. Observamos que a FVCI foi 15x maior nos miocardiopatas em relação ao grupo controle, mas não diferiu em relação às MCDI e MCDC (FVCI % MCDC = 6,83 ± 5,47; MCDI = 5,75 ± 4,45; controle = 0,42 ± 0,14*; p<0,001). Não houve relação da FCVI com a sobrevida dos pacientes com miocardiopatias (MCDI-FVCI £5,53 (20,0%) ou >5,53 (0,0%) (p=0,249), e na MCDC-FVCI £5,53 (0,0%) ou >5,53 (7,7%) (p=0,587) e apenas na MCDI a fração de ejeção do ventrículo esquerdo (FEVE) teve relação com a FVCI. O diâmetro diastólico final do ventrículo esquerdo não se correlacionou com a FCVI nas duas etiologias. Conclusão: a fibrose miocárdica não diferiu entre as duas etiologias, não se correlacionou com o prognóstico das MCDC e MCDI e apenas na MCDI ela se correlacionou com a FEVE. / Dilated cardiomyopathies represent 87% of all cardiomyopathies and they have adverse prognosis with high morbidity and mortality. There are several prognostic markers, however, a structural one has not been described yet. Seems to be very important to find out whether morphological changes upon myocardial structure would affect the prognosis. We studied, using endomyocardial biopsy and 2D-echocardiogram, 9 patients with no structural myocardial changes (control) and 45 patients with severe dilated cardiomyopathies. They were divided according the etiology of cardiomyopathy into idiopathic group (IDCM) or Chagas group (CDCM). We analyzed the correlation between interstitial myocardial collagen (ICVF) and survival rates. We also evaluated the difference of ICVF between these groups and whether it correlates with geometric and functional changes of the heart. We observed that ICVF was 15 times higher in cardiomyopathies patients than in control group, but it did not differ between CDCM and IDCM (ICVF% CDCM = 6.83 ± 5.47; IDCM = 5.75 ± 4.45; control = 0.42 ± 0.14*; p<0.001). The ICVF did not correlate to survival rate in cardiomyopathies patients (IDCM-ICVF £5.53 (20.0%) or >5.53 (0.0%) (p=0.249), and CDCM-ICVF £5.53 (0.0%) or >5.53 (7.7%) (p=0.587). We observed a significant correlation between ICVF and left ventricular ejection fraction (LVEF) only on DMC, the ICVF did not correlate to left ventricular diastolic diameter in either etiology. Conclusion: the myocardial fibrosis did not differ between these two etiologies, it did not correlate to prognosis either in the IDCM or CDCM and only in the IDCM the ICVF correlated to the LVEF.
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Doença hepática gordurosa não alcoólica (DHGNA) em pacientes morbidamente obesos submetidos à cirurgia bariátrica : correlação entre os achados histopatológicos das biópsias hepáticas intraoperatórias e estado glicêmico basal

Souto, Kátia Elisabete Pires January 2017 (has links)
Introdução: A Doença Hepática Gordurosa Não Alcoólica (DHGNA) tem como causa principal a obesidade. Atualmente não existe tratamento medicamentoso específico para DHGNA. A cirurgia bariátrica surge como uma alternativa de tratamento em pacientes morbidamente obesos. Objetivos: Analisar, através de biópsia hepática intra-operatória, o grau de comprometimento hepático em obesos submetidos à cirurgia bariátrica, correlacionando os achados histopatológicos com o estado glicêmico dos pacientes. Métodos: Estudo de coorte prospectivo incluindo 521 pacientes submetidos à cirurgia bariátrica de julho de 2001 até dezembro de 2016. Os pacientes foram classificados em três grupos de acordo com o status glicêmico basal: 167(32,05%) diabéticos tipo 2 (G1), 132 (25,33%) pré-diabéticos (G2) e 222 (42,61%) obesos normoglicêmicos (G3). Foram obtidas biópsias hepáticas transoperatórias, as quais foram classificadas conforme os critérios de Brunt e do NASH-CRN. As variáveis clínicas e bioquímicas e histológicas foram comparadas antes da cirurgia e durante o seguimento pós-operatório. Resultados: A prevalência de DHGNA nesta coorte foi de 95%. Não houve diferença quanto ao gênero e IMC entre os grupos. Observaram-se taxas mais altas de fibrose (56,4% G1 vs 29,2% G2 vs 28,6% G3 p<0,001) e Esteatohepatite Não Alcoólica (EHNA) (59,4% G1vs 49,2% G2 vs 36% G3 p <0,001) nos pacientes diabéticos. Apenas 1,5 %, dos diabéticos apresentaram histologia normal (vs 7,76% G2 vs 15,7% G3). / Introduction: Obesity is the main cause of nonalcoholic fatty liver disease (NAFLD), for which there is currently no specific medical treatment. Bariatric surgery is a treatment alternative for morbidly obese patients. Objectives: Use an intraoperative liver biopsy to analyze the degree of liver damage in obese patients submitted to bariatric surgery and correlates the histopathological findings with glucose status. Methods: Prospective cohort study of 521 morbid obese patients undergoing bariatric surgery from July 2001 to December 2016, classified into three groups according to their baseline glucose status: 167 (32.05%) type 2 diabetes (G1), 132 (25.33%) pre-diabetic (G2) and 222 (42.61%) normoglycemic obese (G3). Patients using potentially hepatotoxic medications and a history of ethanol consumption or viral hepatitis were excluded. Intraoperative liver biopsies were obtained and classified in accordance with Brunt and NASH-CRN criteria. Clinical, biochemical and histopathological variables were compared before surgery and during postoperative follow-up. Results: The prevalence NAFLD was 95%. There was no intergroup difference for sex and BMI. Higher rates of fibrosis (56.4% G1 vs. 29.2% G2 vs. 28.6% G3 p<0.001) and nonalcoholic steatohepatitis (NASH) (59.4% G1vs 49.2% G2 vs. 36% G3 p <0.001) were observed in the diabetic patients. Only 1.5 % of diabetics showed normal histology (vs. 7.76% G2 and 15.7% G3).
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Exposição a chumbo e comportamento anti-social em adolescentes / Lead exposure and antisocial behavior in Brazilian adolescents

Olympio, Kelly Polido Kaneshiro 12 February 2009 (has links)
Introdução - A intoxicação por chumbo é um conhecido problema de saúde pública e o envenenamento por este metal pode causar danos a vários órgãos, especialmente ao Sistema Nervoso Central de crianças em desenvolvimento. Objetivo geral- estudar a associação entre exposição a chumbo e comportamento anti-social (CAS) em adolescentes brasileiros. Objetivos específicos: a) analisar a associação entre exposição a chumbo e CAS / cometimento de atos infracionais (CAI); b) estudar potenciais fontes de exposição domiciliar a chumbo que mais estão associadas a altas concentrações de chumbo no esmalte dentário (CCED) e; c) avaliar o impacto de alterações metodológicas na técnica de microbiópsia ácida de esmalte dentário superficial (MAEDS) sobre CCED e profundidade da bíópsia. Métodos- Um estudo transversal foi conduzido com 173 jovens (Bauru, SP). MAEDS foram realizadas nestes jovens por dois diferentes protocolos metodológicos. Além disso, questionários sobre comportamento dos adolescentes e exposição a possíveis fontes de contaminação por chumbo foram aplicados a pais e adolescentes. Análises de regressão logística, testes de Wilcoxon e testes t pareados foram aplicados aos dados. Resultados- Odd ratios ajustados para covariáveis indicaram que alta CCED está associada a risco aumentado de exceder o escore clínico para queixas somáticas, problemas sociais, comportamento de quebrar regras e problemas externalizantes (IC 95%). Alta CCED não foi associado com escores elevados de CAI. Os fatores de risco mais associados com alta CCED foram residir em área contaminada ou até 2 km da área contaminada e trabalhar na fabricação de tintas, pigmentos, cerâmicas ou baterias. A profundidade da biópsia, calculada pela fórmula da altura do cilindro, para um dos protocolos, levou a resultados errôneos de profundidade da biópsia, confirmados por testes de perfilometria. Conclusões- A exposição a altos níveis de chumbo parece disparar o estabelecimento de CAS, o que alerta para a necessidade de desenvolvimento e implantação de políticas públicas de saúde que previnam o envenenamento da população por chumbo. Adolescentes foram expostos ao chumbo por algumas fontes estudadas, no Brasil. O esmalte dentário é um marcador fidedigno e a MAEDS é bastante útil e confiável. No entanto, CCEDs não podem ser comparadas entre resultados de pesquisas diferentes quando houver qualquer variação metodológica entre os estudos, havendo a necessidade da padronização do procedimento. / Introduction - Lead poisoning is a long known public health problem. Thus, lead exposure may cause damage to diverse organs, especially in the Central Nervous System of children in developing process. Objectives- a) to analyze the association between lead exposure and antisocial / delinquent behavior; b) to study the potential sources of lead home exposure more associated to high dental enamel lead levels (DELL) and c) to evaluate two distinct enamel biopsy protocols in relation to biopsy depth and DELL. Methods- A cross-sectional study was conducted with 173 adolescents (Bauru, SP, Brazil). Surface dental enamel (SDE) etch-acid microbiopsies were performed in upper central incisors of these youths by two different methodological protocols. In addition, questionnaires about adolescents behavior and about possible sources of lead contamination were responded by youths and their parents. Logistic regression, Wilcoxon and paired t tests were applied to data. Results- Odd ratios adjusted for familial and social covariates indicated that high DELL is associated with increased risk of exceeding the clinical score for somatic complaints, social problems, rulebreaking behavior (T70) and externalizing problems (T63) (CI 95%). High DELL was not found to be associated with elevated SRD scores. The risk factors associated to high DELL were residing in contaminated area or close proximity and working in paints, pigments, ceramic or batteries manufacturing. The biopsy depth, calculated by the cylinder formula, for Protocol II induced misleading results, as confirmed by profilometry tests. Conclusions- It seems that exposure to high lead levels can indeed trigger antisocial behavior, which claims for public policies to prevent lead poisoning. Adolescents were exposed to lead, by some studied sources, in Brazil. SDE, measured by etch-acid microbiopsy, is a reliable biomarker, but DELL could not be compared when there is some methodological variation among the studies. A standardization of the procedure is necessary.

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