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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.
101

Associação de marcadores de proliferação e de apoptose com a resposta à radioterapia e sua importância prognóstica em carcinoma epidermóide de palato mole / Proliferation and apoptosis markers in association with radiotherapy response and their prognostic importance in squamous cell carcinoma of soft palate

Cortelazzo, Marco Antonio 18 April 2007 (has links)
Carcinoma epidermóide de palato mole é relativamente raro, representando em torno de 15% das neoplasias da orofaringe, onde predominam os tumores de base de língua e tonsila palatina. Não há consenso sobre a melhor forma de tratamento para estes tumores, pois apesar de todos os avanços e associações terapêuticas, as taxas de sobrevida têm se alterado pouco nas últimas décadas. Mesmo com os avanços da cirurgia reparadora, minimizando as seqüelas da cirurgia oncológica, a radioterapia exclusiva e/ou associada à quimioterapia é a forma de tratamento mais utilizada em muitos serviços, principalmente para os tumores em estádio clínico avançado. Entretanto, muitos pacientes não apresentam resposta a tal terapêutica. Desse modo, selecionar um grupo de pacientes com maiores possibilidades de resposta à irradiação poderia orientar a melhor indicação terapêutica para cada caso. Sendo assim, os objetivos desse trabalho são avaliar as características demográficas, clínicas, histológicas e a expressão imunoistoquímica das proteínas p53, Ki-67, Bcl-2 e Bax como fatores preditivos de resposta ao tratamento e de sobrevida, em pacientes portadores de carcinoma epidermóide de palato mole submetidos à radioterapia com finalidade curativa. Foram selecionados, retrospectivamente, 73 prontuários de pacientes portadores de carcinoma epidermóide de palato mole admitidos para tratamento no Departamento de Cirurgia de Cabeça e Pescoço e Otorrinolaringologia do Hospital A. C. Camargo, em São Paulo, no período de janeiro de 1970 a dezembro de 2000 que foram submetidos à radioterapia com finalidade curativa e que apresentavam tecido biopsiado, previamente ao tratamento, viável para a confecção e análise da expressão imunoistoquímica dos marcadores em questão, em lâminas de tissue microarray. As variáveis idade, sexo, raça, tabagismo, alcoolismo, grau histológico (G), categoria T e N e estádio clínico (EC) foram correlacionadas com a expressão imunoistoquímica destes marcadores. A idade média dos pacientes foi de 60 anos, com predomínio de pacientes do sexo masculino (83,6%), raça branca (80,8%), tabagistas (86,3%), alcoolistas (76,7%), G1+2 (69,9%) e em EC avançado da doença (72,6%). Não houve diferença estatisticamente significativa entre a expressão dos marcadores em questão e as variáveis estudadas. As análises univariadas de sobrevida em 5 anos evidenciaram que a sobrevida específica por câncer (SEC) foi de 27,1%, sendo significativamente melhor para os pacientes portadores de tumores em categoria T e N iniciais e em estádios clínicos iniciais. A sobrevida global (SG) foi de 24,9% sendo significativamente melhor nos pacientes portadores de tumores em estádios clínicos iniciais. Em relação à imunorreatividade dos marcadores estudados, não observamos diferenças estatisticamente significativas quanto à sobrevida específica por câncer e global. A análise multivariada da SEC em 5 anos evidenciou que EC avançado, grau histológico G3 e imunoexpressão de p53 foram variáveis independentes, associadas a pior prognóstico (p < 0,100). Para a sobrevida global, somente EC avançado foi identificado como variável independente associada a pior prognóstico. Conclusão: pacientes com tumores em estádios clínicos iniciais e/ou G1+2 e/ou que não expressam p53 têm melhor prognóstico. / Squamous cell carcinoma of the soft palate is rare and represents about 15% of the oropharynx cancer, where there is prevalence of tumors of the base of tongue and palatine tonsil. There is no consensus about the best form of treatment for these tumors because, despite all advances and therapeutic associations, there has not been major changes in overall survival in the last decades. In spite of the advances of reconstructive surgery, which has reduced the sequelae of oncologic surgery, radiotherapy alone or in association with chemotherapy are the most used treatments, especially for tumors in advanced clinical stage, mostly because of the sequelae of surgical treatment. However, many patients have a poor response to this therapeutic. This way, selecting a group of patients with more possibilities of response to irradiation could be used in the selection of the best therapeutic for each case. Because of this, the objective of this paper is to evaluate demographic, clinical and histological characteristics and the immunoistochemical expression of p53, ki-67, Bcl-2 and Bax proteins as predictive factors of response to treatment and survival in patients with squamous cell carcinoma of soft palate submeted to radiotherapy with curative intent. We selected, retrospectively, 73 clinical charts of patients with squamous cell carcinoma of soft palate admitted for treatment in the Department of Head and Neck and Otorrinolarynxlogy Surgery of A. C. Camargo Hospital, in São Paulo, from 1970 to 2000, submitted to radiotherapy with curative intent and who had tissue biopsy - before treatment - which had a viable paraphin block analyze the immunoistochemical expression of the studied markers, in plates of tissue microarray. Variables as age, sex, race, smoking, alcoholism, histological degree, T and N categories and clinical stage were correlated with the immunoistochemistry expression of these markers. Mean age was 60 years, mostly patients were males (83.6%), white (80.8%), smokers (86.3%), alcoholics (76.7%), the histologic degree was G1 and G2 (69.9%) and most were diagnosed in advanced clinical stages (72.6%). There was no statistically meaningful difference between the expression of the studied markers and the studied variables. Univaried analysis of survival in 5 years showed that cancer specific survival was 27.1%, which was significantly better for those patients with tumors in early T and N categories and initial clinical stages. Overall survival was 24.9%, significantly better for patients with tumors in initial clinical stages. About the immuno-reactivity of the studied markers, we did not find statistically significant differences for overall survival cancer and specific survival. Multivaried analysis of cancer specific survival in 5 years showed that advanced clinical stage, histological degree 3 and p53+ were independent variables, associated with a worst prognosis (p<0.100). For overall survival, only advanced clinical stage was an independent prognostic variable. Conclusion: patients with tumors in advanced clinical stages and/or histological degree 1 + 2 and/or that do not express p53 have a better prognosis.
102

Dynamic analysis of serum tumor marker decline during anti-cancer treatment using population kinetic modeling approach

You, Benoît 11 March 2011 (has links) (PDF)
Several cancers are associated with abnormal serum concentrations of tumor markers such as prostate specific antigen (PSA) in prostate tumor diseases, alfa-fetoprotein (AFP) or human chorionic gonadotrophin (hCG) in germ cell tumors or persistent gestational trophoblastic diseases (GTD). Cancer treatment should induce decline of serum tumor marker concentrations. The predictive values of many kinetic parameters supposed to characterize tumor marker declines such as nadir, time-point cutoff, half-life, time to normalization etc..., have been reported in previous studies. However very few of them have been used in routine due to the lack of outcome reproducibility. Population pharmacokinetic approach-based modeling is already used in pharmacokinetic studies. It might be helpful to characterize tumor marker decline equations dynamically and overcome limitations of previous studies. The feasibility and the relevance of this approach were assessed in 4 studies involving: PSA titers in patients with prostate adenoma or cancer treated with surgery; hCG-AFP in non-seminomatous germ cell tumor patients treated with BEP regimen (Bleomycin-Etoposide-Cisplatin) and hCG in GTD patients treated with methotrexate. Tumor marker decline modeling was feasible in all studies provided the methodology was adjusted to marker specificities. Apparent clearance of hCG and PSA might enable identification of patients with unfavorable decline profiles and thereby with high risk of relapse. Confirmatory studies with independent cohorts of patients are warranted
103

A fast, scalable acoustic resonator-based biosensor array system for simultaneous detection of multiple biomarkers

Munir, Farasat 17 August 2012 (has links)
This thesis is about the design of a biosensor system for detection of multiple cancer biomarkers. Accurate diagnosis and prognosis of cancer requires early detection. Equally important, though, is the measurement of biomarker-velocity and detection of multiple biomarkers. Early detection requires highly sensitive biosensors capable of detection at very low concentrations of target molecules. Biomarker-velocity can be measured by monitoring concentration of target molecule over a period of time. This requires a system which is very easy to use, fast, flexible, inexpensive and portable, thus enabling its ubiquitous presence at the point of care. For detection of multiplexed biomarkers, biosensors which easily lend to array configuration are required. Conventional techniques do not fulfill either all or some aspects of the requirements listed above. In this work, we present the design of a biosensor system, keeping in view the desired features described above, to achieve the ultimate goal of enabling ubiquitous presence of biosensor at the point of care. We focus on acoustic transducer based biosensors. The two fundamental components of design in an acoustic biosensor are the design of an acoustic transducer and the design of a novel electrical interface for the transducer. For transducer design, we introduce and present the design of a single structure, GHz range, multi-mode acoustic resonator. We present this as a suitable transducer for liquid phase biosensors, which is the preferred medium for sensing of cancer biomarkers. We explore the underlying physics and do experimental and theoretical characterization of this device. The transducer needs to be functionalized with a chemically sensitive layer which performs the molecular recognition of cancer biomarkers. We present the experimental exploration of a reversible and oriented immobilization based Histidine-Ni(2+) interaction which used NTA as the chelator for anchoring onto the device. Then we discuss the microfluidic design to enable liquid phase operation. We used SU-8 polymer barriers for liquid containment and addressed the challenges of making it compatible with ZnO based devices. An electrical interface is needed to excite and extract the sensor response. We have presented here a novel method to measure and track a resonator's response and extract its characteristic parameters. This method measures the wideband frequency response of the resonator with a much simpler setup as compared to conventional methods. We have proposed and demonstrated the use of a white noise signal as a viable signal for broadband excitation of resonator-based sensing platforms. We have also established, shown through simulation and prototype measurements, the feasibility of the proposed method. The accuracy and speed of the system can be further greatly improved by FFT-based digital implementation of the spectral analysis system. We have presented an example hardware implementation of FFT-based signal analyzer, and have discussed the hardware resources required for actual implementation in a chip form. Lastly we discuss the measurement protocol and sensor results for head and neck cancer and prostate cancer biomarkers. These results demonstrate the usability of the proposed sensor system for detection of cancer biomarkers.
104

Nanocarrier mediated therapies for the gliomas of the brain.

Agarwal, Abhiruchi 21 January 2011 (has links)
Existing methods of treating glioma are not effective for eradicating the disease. Therefore, new and innovative methods of treatment alone or in combination with existing therapies are necessary. Delivery of therapeutic agents through delivery carriers such as liposomes diminishes the harmful effects of the agent in healthy tissues and allows increased accumulation in the tumor. In addition, targeted chemotherapy using liposomes provides the opportunity for further increase in drug accumulation in tumor. However, the current targeting strategies suffer accelerated plasma clearance and are not advantageous in improving efficacy. The search for new tumor targets, novel ligands, new strategies for targeting, and particle stabilization will advance our ability to improve delivery at the tumor level while decreasing toxicity to normal tissues. The global objective of this thesis was to improve the status of current liposomal therapy to achieve higher efficacy in tumors. Here, we show a novel mechanism to increase targeting to tumor while uncompromising on the long circulation of stealth liposomes. Long circulation is essential for passive accumulation of the nanocarriers due to EPR effect, in order to see benefits of targeting. Using phage display technique, a variety of tumor specific peptides were identified for use as targeting moieties. One potential advantage of the approach proposed here is the rapid identification of patient tumor specific peptide that evades the RES. This could lead to the development of a nanocarrier system with high avidity and selectivity for tumors. Therefore, tumor accumulation of the targeted formulations will be higher than that of non‐targeted liposomes due to increased drug retention at the tumor site and uncompromised blood residence time.In addition, it has been shown that the distribution of nanocarriers, spatially within the tumor, is limited that might further hinder the distribution of the encapsulated drug, thereby limiting efficacy. It is necessary to release the drug from within the nanocarrier to promote increased efficacy. Here, we were able to address the problem of drug diffusion within the tumor interstitium using a combination therapy employing a remotely triggered thermosensitive liposomal chemotherapeutic. We fabricated a thermosensitive liposomal nanocarrier that maintained its stability at physiological temperature to minimize toxicity to healthy cells. We, then, showed a remote triggering mechanism mediated by gold nanorods heated via NIR can help in achieving precise control over the desired site for drug release. These strategies enabled increased drug availability at the tumor site and contributed to tumor retardation. Additionally, we show that the synergistic therapy employing gold nanorods and thermosensitive liposomes may have great potential to be translated to the clinic.
105

Acoustic wave biosensor arrays for the simultaneous detection of multiple cancer biomarkers

Wathen, Adam Daniel 11 August 2011 (has links)
The analysis and development of robust sensing platforms based on solidly-mounted ZnO bulk acoustic wave devices was proposed. The exploitation of acoustic energy trapping was investigated and demonstrated as a method to define active sensing areas on a substrate. In addition, a new "hybrid" acoustic mode experiencing acoustic energy trapping was studied theoretically and experimentally. This mode was used as an explanation of historical inconsistencies in observed thickness-shear mode velocities. Initial theoretical and experimental results suggest that this mode is a coupling of thickness-shear and longitudinal particle displacements and, as such, may offer more mechanical and/or structural information about a sample under test. Device development was taken another step further and multi-mode ZnO resonators operating in the thickness-shear, hybrid, and longitudinal modes were introduced. These devices were characterized with respect to sample viscosity and conductivity and preliminary results show that, with further development, the multi-mode resonators provide significantly more information about a sample than their single-mode counterparts. An alternative to resonator-based platforms was also presented in the form of bulk acoustic delay lines. Initial conceptual and simulation results show that these devices provide a different perspective of typical sensing modalities by using properly designed input pulses, device tuning, and examining overall input and output signal spectra.
106

p63 and potential p63 targets in squamous cell carcinoma of the head and neck /

Boldrup, Linda, January 2008 (has links)
Diss. (sammanfattning) Umeå : Univ., 2008. / Härtill 4 uppsatser.
107

Uveal melanoma : cytogenetics, molecular biology and tumor immunology /

All-Ericsson, Charlotta, January 2002 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst., 2002. / Härtill 4 uppsatser.
108

Quantitative analysis of melanoma transcripts : with emphasis on methodological and biological variation /

Farnebäck, Malin, January 2004 (has links) (PDF)
Diss. Linköping : Univ., 2004.
109

Stanovení perioperačních prognostických faktorů karcinomu mléčné žlázy / Perioperative prognostic factors in breast cancer

Černá, Monika January 2012 (has links)
Introduction: Breast cancer still remains the most common malignancy in women and its incidence is slowly increasing. A marked reduction of mortality has been achieved in the last 10 years thanks to modern diagnostic methods, mammary screening, and comprehensive and targeted cancer therapy. Modern diagnostic capabilities not only allow early diagnosis of a primary tumor lesion and precise determination of its biological nature before commencing treatment, but they also enable early diagnosis of local and regional recidives, including diagnosis of metastases in distant organs. In addition to clinical examination, conventional and complementary imaging examinations and tumor markers our objective was to determine the importance and use of growth factors in relation to the overall prognosis. The growth factors physiologically act already during the ontogenetic period when they control cell growth, proliferation, differentiation and apoptotic processes. It is known that they take part in the tumor growth processes which are characterized by autonomous behavior, increased proliferative activity, distinct differentiation activity and reduced apoptosis. Growth factors work as autoregulation factors in the neoplastic process as well as through their paracrine effects mediated by more or less specific receptors....
110

Ovlivnění hladiny nejpoužívanějších nádorových markerů a jejich intepretace (ovlivnění systémovými a zánětlivými onemocněními) / Interpretation of Common Used Tumor Markers Affectedy by Systemic and Inflammatory Diseases

Čásová, Miroslava January 2015 (has links)
Interpretation of Common Used Tumor Markers Affected by Systemic and Inflammatory Diseases Introduction: An examination of tumor markers is often made as a basis for the successful diagnosis and follow-up treatment of patients with malignant tumors. However, are tumor markers truly significant by themselves, or are they just a baseline quantitative expression of value that we use to diagnose a patient as better or worse based on it increasing or decreasing value? Objective: This paper attempts to answer the question of what factors can affect serum protein and mucin markers and thus lead to a misinterpretation of their results. Methods: Tumor markers were determined by isotopic and non-isotopic laboratory analysis methods, using operational protocols of the immunoanalytic laboratory. All methods were checked using internal quality control, and four times a year using an external quality control. Additionally, 16 236 samples were analysed using 3180 probands during the period 2008-2014. Results: We discovered that in premenopausal women, the markers AFP, CA 125 and HE 4 rise during ovulation peak periods while other markers changed minimally or not at all. However, in postmenopausal women, we proved the incidence of a false positivity marker. With women in the 1st and 2nd trimester of pregnancy, the...

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