Articular cartilage has a low propensity for self-repair, due to which 27 million people are affected by osteoarthritis every year in North America. The current repair techniques used for cartilage defects possess flaws that reduce long-term clinical success. Tissue engineering carries with it the promise of engineering hyaline-like cartilage with physical and biochemical properties, similar to that of native cartilage. This being said, the primary objective of my project was to engineer clinically relevant sized articular cartilage constructs. To achieve my objective, first, I investigated the effect of continuous culture on cartilaginous tissue growth. Constructs grown under continuous media flow significantly accumulated more collagen and glycosaminoglycan, and displayed a stratified morphology, similar to that found in native cartilage. The second goal was to further increase chondrocyte proliferation, and extracellular matrix (ECM) accumulation. To achieve this, constructs were grown in a bioreactor with media supplemented with 14 mM sodium bicarbonate (NaHCO3). Constructs cultivated in the bioreactor with NaHCO3 supplementation exhibited a significant (p<0.05) increase in ECM accumulation (a 98-fold increase in glycosaminoglycans and a 25-fold increase in collagen content), cell proliferation (a 13-fold increase), and thickness (a 28-fold increase) compared to all other conditions (static and reactor without NaHCO3 supplementation). The third goal was to engineer cartilage constructs with as little cells as possible, reducing donor site morbidity. From the results obtained, it was evident that the monolayer constructs outperformed all the other constructs (pellet, biopsy, and minced). The final goal was to understand the underlying reason for the increased proliferation. First, I investigated if there were any differences present in intracellular pH (pHi) and intracellular buffering capacity. Second, I determined the role of extracellular pH (pHe) on cell proliferation. In an effort to accurately achieve this, I, for the first time, have reported on measuring pHi of chondrocytes while still in culture (2D and 3D cultures) using a confocal microscope. This study demonstrated the importance of extracellular environments, such as pHe, extracellular buffering capacity, and the presence of carbon dioxide and bicarbonate ions for chondrocyte proliferation. / Thesis (Ph.D, Chemical Engineering) -- Queen's University, 2012-10-30 19:19:32.026

Introduction: Targeted biopsy of tumour-suspicious lesions detected in multiparametric magnetic resonance imaging (mpMRI) plays an increasing role in the active surveillance (AS) of patients with low-risk prostate cancer (PCa). The aim of this study was to compare MRI/ultrasound-fusion biopsy (fusPbx) with systematic biopsy (sysPbx) in patients undergoing biopsy for AS. Methods: Patients undergoing mpMRI and transperineal fusPbx combined with transrectal sysPbx (comPbx) as surveillance biopsy were investigated. The detection of Gleason score upgrading and reclassification according to Prostate Cancer Research International Active Surveillance criteria were evaluated. Results: Eighty-three patients were enrolled. PCa upgrading was detected in 39% by fusPbx and in 37% by sysPbx (p = 1.0). The percentage of patients who were reclassified in fusPbx and sysPbx (p = 0.45) were 64 and 59% respectively. ComPbx detected more frequently tumour upgrading than fusPbx (71 vs. 64%, p = 0.016) and sysPbx (71 vs. 59%, p < 0.001) and more patients had to be reclassified after comPbx than after fusPbx or sysPbx alone. Conclusions: The combination of fusPbx and sysPbx outperforms both modalities alone with regard to the detection of upgrading and reclassification in patients under AS. Because a high missing rate of significant PCa still exists in both biopsy modalities, a combination of fusPbx and sysPbx should be recommended in these patients.

Prostate cancer diagnostic algorithm Aim: The aim of the study is to implement the latest scientific knowledge in the diagnosis of prostate cancer (PC). We focused on tumor markers, imaging methods, prostate biopsy methodology and we created a diagnostic algorithm based on a review of current literature in combination with our own experience. Material and methods: The algorithm is divided into several branches, which have been individually subjected to clinical studies. Due to the low sensitivity and specificity of PSA, prostate health index (PHI) was added to the first line of patient stratification. 787 patients were primarily examined and these subsequently underwent radical prostatectomy. PHI levels were compared with definitive staging and grading. Cut-off values for PC detection and high-risk stratification, including locally advanced PC were determined. Next, 320 patients underwent prostate biopsy followed by radical prostatectomy. The cohort was further divided into two subgroups, patients with GS = 6 and patients with GS > 6. The ability of PHI to distinguish between insignificant and significant prostate cancer was evaluated. In a multicentric study with 395 patients, PHI with additional markers (tPSA, PSAD) and multiparametric magnetic resonance imaging of prostate (mpMRI) was assessed....

Purpose Lower serum vitamin D levels have been associated with an increased risk of aggressive prostate cancer. Among men with localized prostate cancer, especially with low-or intermediate-risk disease, vitamin D may serve as an important biomarker of disease aggression. The aim of this study was to assess the relationship between adverse pathology at the time of radical prostatectomy and serum 25-hydroxyvitamin D (25-OH D) levels. Methods This cross-sectional study was carried out from 2009 to 2014, nested within a large epidemiologic study of 1,760 healthy controls and men undergoing prostate cancer screening. In total, 190 men underwent radical prostatectomy in the cohort. Adverse pathology was defined as the presence of primary Gleason 4 or any Gleason 5 disease, or extraprostatic extension. Descriptive and multivariate analyses were performed to assess the relationship between 25-OH D and adverse pathology at the time of prostatectomy. Results Eighty-seven men (45.8%) in this cohort demonstrated adverse pathology at radical prostatectomy. The median age in the cohort was 64.0 years (interquartile range, 59.0 to 67.0). On univariate analysis, men with adverse pathology at radical prostatectomy demonstrated lower median serum 25-OH D (22.7 v 27.0 ng/mL, P = .007) compared with their counterparts. On multivariate analysis, controlling for age, serum prostate specific antigen, and abnormal digital rectal examination, serum 25-OH D less than 30 ng/mL was associated with increased odds of adverse pathology (odds ratio, 2.64; 95% CI, 1.25 to 5.59; P = .01). Conclusion Insufficiency/deficiency of serum 25-OH D is associated with increased odds of adverse pathology in men with localized disease undergoing radical prostatectomy. Serum 25-OH D may serve as a useful biomarker in prostate cancer aggressiveness, which deserves continued study. (C) 2016 by American Society of Clinical Oncology

Thesis (MScMed (Dept. of Biomedical Sciences. Anatomy and Histology) --University of Stellenbosch, 2007. / Thyroid nodules are a common clinical problem encountered by physicians, surgeons and radiologists who deal with the head and neck region. However, most follicular lesions of the thyroid are benign, so that the indications for surgery should be as accurate as possible. The morphological difficulty on fine-needle aspiration biopsy (FNAB) of reliably distinguishing preoperatively between benign and malignant lesions has led to a search for ancillary methods that can assist with the diagnosis. The aim of the first study was to develop a cytological scoring system to improve diagnostic accuracy of fine-needle aspiration biopsy of papillary carcinomas with special reference to the follicular variant of papillary carcinoma. The objective of the second study was the application of immunodiagnostic markers Galectin-3 and HBME-1 to histology tissue sections and their corresponding fine-needle aspiration cytology smears to assess their value in distinguishing benign from malignant thyroid lesions. In the first study 16 different cytological features such as background, architecture and cellular morphology were quantatively assessed and scored. Only 14 of the 16 variables were statistically significant. The statistical analysis demonstrated that a score ≥ 4 was indicative of a papillary carcinoma with a sensitivity of 96%. A score < 4 suggested a benign multinodular goiter with a specificity of 97%. In the second study Galectin-3 and HBME-1 were applied to histology tissue sections and their corresponding fine-needle aspiration cytology smears. Statistical analyses showed that the sensitivity of immunohistochemistry for diagnosing malignancy was better than the immunocytochemistry, but the specificity of immunocytochemistry was superior. Furthermore the diagnostic accuracy of immunohistochemistry (86%) and immunocytochemistry (88%) using co-expression of these two antibodies was excellent. In this study on immunocytochemistry, papillary carcinomas were clearly identified with a 100% co-expression in the classic and 71% in the follicular variant of papillary carcinoma. For the surgeon the identification of papillary carcinoma is critical, as this determines the extent of surgery. Similary, the confirmation of a non-neoplastic lesion may prevent surgery. In most cases follicular neoplasms, benign or malignant, will usually be excised for histopathology, prior to definite therapy. These studies show that the implementation of ancillary methods such as a scoring system and immunodiagnostic markers can improve the diagnostic accuracy of thyroid fine-needle aspiration biopsies in our laboratory. This may lead to better management of thyroid nodules. However, it is advisable that cytopathologists always take all the clinical features and image analyses into consideration before making a diagnosis.

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.

Introdução:O papel das biopsias do miocárdio, tem tido relativa importância em cardiologia, sendo método diagnóstico fundamental em um pequeno número de patologias do coração como na doença por depósito de glicogênio, amiloidose, hemocromatose e nas miocardites. Ao longo dos anos, o desenvolvimento de diferentes procedimentos que possibilitam a obtenção de fragmentos do tecido cardíaco passou por diversos estágios e evoluída miocardiectomia a céu-aberto aos cateteres endovasculares, passando por procedimentos com agulhas de punção. Estes apesar de estar em desuso atualmente, têm particular importância por proporcional acesso ao miocárdio e a cavidade ventricular esquerda. Paralelamente, a terapia celular tem sido utilizada na recuperação e preservação da função cardíaca em coronariopatia crônica e na doença de chagas. As punções biópsias do coração ressurgem como possível método alternativo de acesso ao miocárdio e implante de material biológico para terapia celular. Objetivos:apresentar instrumento de punção, biopsia e injeção intramiocárdica de material biológico, padronizar a técnica e atestar a segurança do método.A adaptação consiste em um sistema de escarificação do miocárdio para permitir melhor fixação de células-tronco. O objetivo do presente trabalho visa apenas o desenvolvimento da agulha e testar histologicamente a qualidade das biópsias. Método: O instrumento para punção e injeção de material biológico é composto por uma agulha exterior (1), chamado de acoplamento de infusão, o qual contém na sua extremidade uma ponta romba (2) e vários orifícios de 0,5 mm de diâmetro (3). Internamente, está equipado com uma agulha com um mandril fechado, que quando introduzidas no exterior, pode ser mobilizada para dentro para encher os orifícios laterais ocluindo ou soltá-los. O procedimento para a produção de microlesões micro é feito através da troca do mandril de ponta romba (durante o procedimento) por um mandril escova (4), provido de microcerdas que são estruturalmente concebidas para preencher os orifícios com a exteriorização das pequenas cerdas (5). O instrumento está equipado com um mecanismo de bloqueio, que permite a sua mobilização perfeita como uma única unidade de microlesões ou, ainda pode ser utilizado somente como uma agulha externa, de modo que pode tornar-se um instrumento de injeção biológica. Resultado: A técnica já foi testada em modelo suíno vivo mostrando sua viabilidade e segurança. Como resultados são apresentados aspectos macroscópicos e microscópicos do coração (Corantes Hematoxilina eosina, Tricrômico Masson e Azul de Evans).Conclusão: No tocante a sua função o novo Instrumento de punção/infusão tem por característica principal o fato de ser multifuncional. Permite ao operador acessar a cavidade ventricular esquerda por via transtorácica sem risco de lesão (perfuração), das artérias coronárias. Permite penetrar o miocárdio sem laceração das fibras musculares pela divulsionamento das mesmas e escarificar o miocárdio. gerando micro-lesões musculares por intermédio de seu mandril com cerdas, promovendo a \"inflamação benéfica ao processo de transplante celular. / Introduction: The role of myocardial biopsy has had relative importance in cardiology, being fundamental diagnostic method in a small number of diseases of the heart as in glycogen deposit disease, amyloidosis, hemochromatosis and in miocardites. Over the years, the development of different procedures that allow obtaining cardiac tissue fragments went through several stages and evolved from open miocardiectomy to endovascular catheters, going through procedures with puncture needles. These despite being in disuse today, have particular importance for offering access to myocardium and left ventricular cavity. At the same time, the Cellular therapy has been used in the recovery and preservation of cardiac function in chronic coronary artery disease and Chagas disease. The puncture-heart biopsies to re-emerge as a possible alternative method of access to the myocardium and implantable biomaterial for cell therapy. Objectives: Objectives: to present puncture tool, biopsy and intramyocardial injection of biological material, standardizing the technical and certify the safety of the method. The adaptation allows in a myocardial scarification system for making possible a better stem cells fixation. The objective of this study covers only the development of needle and test, macroscopically and histologically the quality of biopsies. Methods: The instrument for puncturing and injection of biological material is composed of an external needle (1), called coupling infusion, which contains at its end a blunt tip (2) and multiple 0.5 mm diameter holes (3). Internally it is fitted with a blunt mandrill needle, which when introduced into the external, can be mobilized inside to fill the lateral holes occluding or releasing them. The procedure for producing micro lesions is done by exchanging the blunt mandrill (during the procedure) for a brush-mandrill (4), provided with micro bristles that are structurally designed to fill the holes with small exteriorization of bristles (5). The instrument is equipped with a locking mechanism, which allows its perfect mobilization as one single unit for micro lesions or it can be used only as an external needle so it can become a biological injection instrument.Result: The technique has been tested in vivo pig model showing its feasibility and safety. The results are presented through macroscopic and microscopic aspects of the heart (dyes hematoxylin eosin, Masson Masson and Evans blue).Conclusion: Regarding its function the new instrument is to be multifunctional main feature. It allows the operator to access the left ventricular cavity through transthoracic without risk of injury (perforation) of the coronary arteries. It allows penetrate the myocardial laceration of the muscle fibers by divulsionamento of them and rip the myocardium. generating muscle micro-injuries through its arbor with bristles, promoting \"inflammation beneficial to the cell transplant process.Key words: heart biopsy puncture, infusion of stem cells in the heart.

A ressecção ampla do trajeto de biópsia junto ao tumor faz parte da técnica cirúrgica oncológica para evitar os riscos de implante de células tumorais e recidiva local e/ou sistêmica da doença. O objetivo deste estudo foi verificar se havia risco de contaminação por células neoplásicas no trajeto da biópsia. Realizou-se um estudo prospectivo dos trajetos de biópsias de pacientes operados por tumores musculoesqueléticos malignos no Instituto de Ortopedia e Traumatologia da Faculdade de Medicina da Universidade de São Paulo no período de abril de 2006 a abril de 2007. Foram estudados por histopatologia 25 casos. Houve implante de células neoplásicas em 32% dos trajetos. Quando foram correlacionados os resultados dos estudos dos trajetos e o uso de quimioterapia neo-adjuvante (p=0,19) não houve significância, mostrando que mesmo com esse tratamento o risco de implante existe. As alterações histológicas mais comuns foram: fibrose acentuada, componente inflamatório leve e neovascularização acentuada. Sugerimos a ressecção tradicional oncológica do trajeto junto com a peça / Wide resection of biopsy tracts to tumors forms part of oncological surgical techniques because of the risk of tumor cell implantation and local and/or systemic disease recurrence. The aim of this study was to investigate the risk of seeding by neoplastic cells along biopsy tracts. This was a prospective histopathological study on biopsy tracts in 25 patients who underwent operations due to malignant musculoskeletal tumors, at the Institute of Orthopedics and Traumatology, School of Medicine of the University of São Paulo, between April 2006 and April 2007. Neoplastic cells were found implanted in 32% of the tracts. Correlation of the results from studying the tracts with the use of neoadjuvant chemotherapy did not present significant findings. This shows that, even with chemotherapy, the risk of implantation exists. The most common histological abnormalities in positive cases were classified as severe fibrosis, mild inflammatory component and severe neovascularization. We suggest that oncological resection of the tract should be carried out together with excision of the specimen

A biópsia por agulha fina é um procedimento importante na investigação de tumores, considerado de baixo-custo, minimamente invasivo e ideal para o fornecimento de um diagnóstico preciso em casos de nódulos da glândula tireóide. Para a realização bem sucedida da biópsia por agulha, a exatidão é essencial e a prática proporciona benefícios significativos tanto na recuperação do paciente, quanto na obtenção de resultados acurados. Esta tese investigou a possibilidade do desenvolvimento de um simulador de realidade virtual para treinamento de biópsia guiada por ultrassom de nódulos da glândula tireóide. O simulador de realidade virtual proposto e desenvolvido é também uma ferramenta educativa, pois além de praticar o procedimento, o usuário pode visualizar tanto um modelo da tireóide para sentir sua textura, quanto um modelo completo do pescoço com todos os seus órgãos internos, podendo ser rotacionado. O sistema consiste de duas interfaces: uma tridimensional, apresentando os modelos virtuais com estereoscopia na mesa de visualização, cuja interação do usuário é feita através do teclado ou dispositivo háptico (Phantom OmniTM); e uma segunda que simula o exame de ultrassom, com todas as funcionalidades de um exame real, sendo manipulada pelo mouse. As duas se comunicam e todo o processo é mostrado na janela do instrutor, que substitui o supervisor orientando o usuário durante o treinamento. O simulador de realidade virtual foi avaliado experimentalmente por profissionais da área médica e tecnológica, sendo aprovado como uma ferramenta para treinamento e ensino de biópsia de nódulos da glândula tireóide. / The fine needle biopsy is an important procedure to investigations in tumors, low-cost considered, minimally invasive and ideal for supplying an accurate diagnosis in cases of thyroid gland nodules. The exactness is essential for the successful accomplishment of the needle biopsy and the practice provides significant benefits in the recovery of the patient, as well as in attainment of accurate results. This thesis investigated the possibility of the development of virtual reality simulator for the training of the ultrasound guided needle biopsy of thyroid gland nodules. The proposed and developed virtual reality simulator is also an educative tool, because besides practicing the procedure, the user can visualize thyroid model to feel its texture, as well as a complete model of the neck with all its internal organs and it can be rotated. The system consists of two interfaces: first is a three-dimensional which presents the virtual models with stereoscopy in the visualization table, whose interaction of the user is made through the keyboard or haptic device (Phantom OmniTM); and second one that simulates the ultrasound images, with all the functionalities of a real examination, manipulated by the mouse. The two interfaces communicate with each other and all the process is shown in the instructor window that substitutes the supervisor and guides the user during the training. The virtual reality simulator was experimentally evaluated by professionals of the medical and technological areas, being approved as a tool for training and education in needle biopsy of the thyroid gland nodules.

Introdução: O transplante renal é amplamente reconhecido como a melhor forma de tratamento para os pacientes que necessitam de terapia de substituição renal. Frequentemente a equipe transplantadora se depara com a difícil questão de determinar se órgãos, provenientes de doadores falecidos e limítrofes ou em parada cardíaca, estão aptos para serem transplantados. É difícil quantificar a intensidade do dano provocado pela isquemia no enxerto a ser utilizado, especialmente se o doador apresentou quadro de instabilidade hemodinâmica com queda significativa da perfusão tecidual e aumento do risco de diminuir a função do enxerto e afetar adversamente sua sobrevida. Desta forma torna-se justificável a utilização da técnica de espectroscopia de fluorescência induzida pelo laser, na tentativa de se avaliar a correlação entre os seus achados e o grau de lesão histológica renal experimental, uma vez que se trata de um método objetivo, não invasivo, rápido e em tempo real que, futuramente, pode ser aplicada nos transplantes renais em humanos. Objetivos: Avaliar a correlação entre os dados da espectroscopia de fluorescência induzida pelo laser e alterações histológicas na isquemia e reperfusão renal em ratos, e se existe diferença significativa na leitura da espectroscopia entre os polos superior, inferior e o terço médio. Materiais e Métodos: Foram utilizados 33 ratos (Rattus norvegicus) machos adultos da linhagem Wistar que, depois de anestesiados, tiveram seus rins esquerdos abordados. Inicialmente os rins foram submetidos à detecção da espectroscopia de fluorescência dos pólos superiores, inferiores e terços médios. As excitações foram geradas por lasers com comprimentos de onda de 408, 442 e 532 nm. Em seguida os pedículos renais esquerdos foram dissecados, isolados e clampeados com auxílio de mini-pinça vascular. Então, os animais foram divididos aleatoriamente em três grupos isquêmicos de 30, 60 e 120 minutos de isquemia quente. Em cada um dos grupos, os rins foram novamente analisados pela espectroscopia de fluorescência, bem como após 5 minutos de reperfusão, utilizando novamente feixes excitatórios com os mesmos comprimentos de onda, nas mesmas regiões renais. Posteriormente os rins esquerdos foram coletados e enviados para estudo histológico. Resultados: O tempo de isquemia mostrou forte influência com a graduação histológica. Com 30 minutos de isquemia, nenhum comprimento de onda (408, 442 e 532 nm) apresentou correlação com a graduação histológica (p = 0,81; p = 0,11; p = 0,21, respectivamente). Com 60 minutos de isquemia, o laser de excitação de 532 nm (na fase de reperfusão) apresentou coeficiente de correlação negativa significativa (r = - 0,61) com a graduação histológica. Na isquemia de 120 minutos, o laser com 442 nm de comprimento de onda (na fase de reperfusão) mostrou o coeficiente de correlação negativa significativa (r = - 0,73) com a graduação histológica. O terço médio renal apresentou média estatística superior à dos polos (p < 0,001) na leitura da espectroscopia de fluorescência. Conclusões: Há correlação entre os dados da espectroscopia de fluorescência induzida pelo laser e as alterações histológicas na isquemia renal em ratos, sendo necessário, durante a investigação, analisar apenas o terço médio renal. / Introduction: Renal transplantation is widely recognized as the best form of treatment for patients who require renal replacement therapy. Often, the transplant team is faced with a difficult question, if organs from deceased marginal donors or non-heart beating donors are able to be transplanted. It is difficult to quantify the intensity of damage caused by ischemia in the graft to be used, especially if the donor had hemodynamic instability with a significant decrease of the tissue perfusion and an increased of the risk of diminishing the graft function which could affect adversely its survival. Thus it is justified to use the technique of laser-induced fluorescence spectroscopy, to assess the correlations between its results and the histological grade in experimental renal injury, since it is an objective, non-invasive, fast and in real-time analysis, which can be applied, in the future, in human kidney transplants. Objectives: To evaluate the correlation between the data of laser-induced fluorescence spectroscopy and histological changes in kidney ischemia and reperfusion in rats, and if there are significant differences of reading between the upper and lower poles and the middle area of such kidneys. Materials and Methods: We used 33 adults male rats (Rattus norvegicus) of Wistar strain, which after anesthetized, had their left kidney addressed. Initially such kidneys were submitted to detection of the fluorescence spectroscopy of the upper pole, lower pole and the middle area. Excitations were generated by lasers having wavelengths of 408, 442 and 532 nm. Then the left renal pedicles were dissected, isolated and clamped. Then the animals were randomized into three ischemic groups of 30, 60 and 120 minutes. In each group, the kidneys were analyzed by fluorescence spectroscopy for the second time, and again after 5 minutes of reperfusion, using excitatory beam with same wavelength, at the poles (upper and lower) and the middle area of the kidneys. Later, the left kidney were collected and sent for histological examination. Results: The ischemia time showed a strong influence on the histological grade. With 30 minutes of ischemia, no wavelength (408, 442 and 532 nm) was correlated with the histological lesions (p = 0.81, p = 0.11, p = 0.21, respectively). With 60 minutes of ischemia, the laser excitation of 532 nm (in the reperfusion phase) showed a significant negative correlation coefficient (r = - 0.61) with the histological grading. In 120 minutes of ischemia, laser with 442 nm wavelength (in the reperfusion phase) showed a significant negative correlation coefficient (r = - 0.73) with the histological grade. The middle area of the kidneys showed a higher average statistically (p< 0,001) than the poles in the reading of fluorescence spectroscopy. Conclusions: There is a strong correlation between the data of laser-induced fluorescence spectroscopy and the histological changes in rats renal ischemia, being necessary, during the investigation, to analyze only the middle area of the kidneys.