• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 8539
  • 3208
  • 2195
  • 1361
  • 953
  • 493
  • 268
  • 258
  • 204
  • 188
  • 130
  • 127
  • 71
  • 60
  • 51
  • Tagged with
  • 22214
  • 4120
  • 1937
  • 1918
  • 1899
  • 1627
  • 1623
  • 1485
  • 1443
  • 1358
  • 1216
  • 1043
  • 1035
  • 1023
  • 966
  • 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.
501

Distúrbios nutricionais e câncer de mama: deficiência de zinco /

Oliveira Filho, Valter de. January 2007 (has links)
Orientador: Laurival Antonio De Luca / Banca: Anete Kinumi Ueda / Banca: Odair Carlito Michelin / Banca: José Costa Andrade / Banca: Angela Marx / Resumo: Foi preocupante o número de biópsias indicadas nas microcalcificações (BIRADS 3 e 4) encontradas em mamografias e o baixo número de casos positivos encontrados. Partindo de pacientes com este diagnóstico radiológico, foi realizada dosagem sé rica de zinco através do método de absorção atômica. Após a realização das biópsias, foi feita a análise estatística dos casos com exame patológico benigno ou neoplasias intra-ductais. Não foram encontradas diferenças entre os grupos quanto a idade, a idade da menarca, a idade da primeira gestação, o número de gestações, nem com o tempo de amamentação. Não foram encontradas diferenças significativas entre os dois grupos, quando relacionados com a classificação BI-RADS. Embora as pacientes com neoplasia intra-ciucta I tenham apresentados níveis séricos de zinco abaixo do grupo controle, este valor não foi significativo (p>O,05), não podendo ser considerado como fator preditivo de risco. / Abstract: The indication of biopsy in the cases of microcalcification (BI-RADS 3 and 4) detected by mammography and the small number of positive results found at these biopsies causes concern among the authors. Thus, serum zinc concentrations were measured by the atomic absorption method in patients with this radiologic diagnosis. Following biopsy performance, the cases of benign pathologic findings or intraductal neoplasia were statistically analyzed. No differences between groups were found in age, age at menarche, age at first pregnancy, number of pregnancies and breastfeeding duration. No significant differences between groups were found regarding BI-RADS c1assification. Although serum zinc concentrations were lower in the patients with intraductal neoplasia than in controls, statistical difference was not significant (p>O,05). Thus, this parameter could not be considered as a predictive risk facto... / Doutor
502

Functional roles of interlukin-8 in epstein-barr virus-positive nasopharyngeal carcinoma cells

Lo, Ming Chu 01 January 2013 (has links)
No description available.
503

A statistical classification of breast cancer patients by degree of nodal metastases

Wilson, Sandra Lee January 1977 (has links)
Recently the traditional primary method of treatment for breast carcinoma — the Halsted radical mastectomy — has been challenged. It is felt by some people that other methods may be more appropriate for certain women. Quality of life and the patient's preferences are being considered in addition to the strictly medical aspects of the problem. One procedure that attempts to increase the quality of life for certain women is the selective biopsy. Women who are proven to have lymph node metastases at the biopsy are spared a mastectomy and treated by radiation since surgery cannot remove all of the cancer. A study was undertaken at the British Columbia Cancer Institute of selective biopsy patients diagnosed between 1955 and 1963 in order to assess the procedure in British Columbia. After studying survival for selective biopsy patients and others, it was concluded that the procedure should continue to be recommended. Since only 14% of the patients now referred to BCCI have had a selective biopsy, I decided to try to find a statistical method for assessing the probability of nodal metastases. The problem is one of statistical classification. The literature on the theory of several statistical models was reviewed. Two models were chosen for the problem: linear discriminant analysis and logistic regression. The classification procedure most often used is discriminant analysis. However, the linear discriminant model assumes a normal distribution and common covariance matrix for the vector of observations. Medical data is often non-normal and even discrete. The logistic probability model works well with such data. Both models were then used to study the selective biopsy problem. The patients of the BCCI study were used as a training set to estimate the parameters of the discriminant function and the logistic probability function. Then each estimated function was used to classify the patients as a measure of the goodness of fit of the models. The logistic regression correctly classified slightly more of the patients than the discriminant analysis did. Because of the iterative nature of the logistic regression, the execution time for the logistic regression was longer than for discriminant analysis, but not beyond practical limits. .The variables that were significant in the statistical analyses could be used to help the physician make a clinical assessment of the lymph nodes of a woman with breast carcinoma. The variables indicate areas where further research would be useful. / Science, Faculty of / Mathematics, Department of / Graduate
504

Developing new immuno-oncology drugs from traditional Chinese medicine

Li, Yang 28 October 2020 (has links)
The most exciting area in current cancer research is immuno-oncology, which aims to develop immunotherapy that activates the human immune system to attack cancers. However, we still lack broadly effective drugs and drug targets for this promising new cancer treatment modality. In an attempt to seek new immuno-oncology drugs that particularly target the antitumor innate immunity, our lab had previously screened traditional Chinese herbal medicine and found that water extract from a medicinal plant, Alocasia Cucullata (AC), has strong anticancer activity in mouse solid tumor models and acts partly by promoting antitumor, proinflammatory macrophages. However, the active components responsible for this exciting immuno-oncology activity and the corresponding immune targets are unknown. Therefore, the aim of my PhD study is to develop chemical biology strategies to isolate and purify the active components of AC from the crude water extract and identify the corresponding cellular targets and mechanisms. Results from my study identified two separable activities and active components, one smaller than 3K and the other larger than 100K, which work synergistically to simulate antitumor macrophages. Further analysis revealed the >100K active component is a large polysaccharide that binds to multiple Toll-like Receptors (TLRs) critical for activating proinflammatory M1-type macrophages. Identity of the Nonetheless, I was able to clean up this fraction by 50 fold and perform RNAseq to examine the innate immune targets of this intriguing drug lead and found it acts to differentiate monocytes to macrophages. Overall my PhD thesis has explored new chemical biology strategies to purify and characterize active components from traditional Chinese medicine towards new drug development and developed a variety of cell-based immune activity assays for identifying and characterizing novel innate immune drug targets and mechanisms
505

Bioinformatic Analysis to Identify and Understand Aberrant DNA Methylation Pattern Associated with Pancreatic Cancer

Zamani, Mariam January 2021 (has links)
In this study, we searched for significant hypo and hyper methylation CpG (5'-C-phosphate-G-3') probes from The Cancer Genome Atlas (TCGA) datasets. First, the relationship between hypo and hypermethylation pattern in significantly expressed genes associated in pancreatic ductal adenocarcinoma (PDAC) was analyzed using computational methodologies in R package. This was done by combining DNA methylation (DM) and gene expression (GE) information, and their corresponding metadata (i.e., clinical data and molecular subtypes) and saved as R files. Next, examination of differentially methylated CpG sites (DMCs) between two groups (normal vs tumor) was identified gene sets. From this analysis, we found nine (09) overexpressed hypomethylated and six (06) under expressed hypermethylated genes near significant CpG probes. Results from this work will shed light on the relationship between CpG methylation and gene expression associated with PDAC.
506

Clinical Significance of Breast Cancer Stem Cells

Dias, Kay January 2014 (has links)
Tumour initiation and progression is thought to be driven by a small population of tumor initiating cells (TICs) or cancer stem cells (CSCs), which have the capacity to migrate and cause metastases and contribute to tumour relapse. These cells possess properties that are similar to those of normal tissue stem cells, which include the capacity to undergo self-renewal as well as the capacity to give rise to more differentiated progenitor cells, which comprise the bulk of the tumour cell population. Thus far, the clinical significance of these cells in breast cancers has not been extensively explored with regard to their relationship with tumour pathology or patient survival. In this thesis we evaluate the presence of these cells in terms of clinicopathological tumour characteristics and patient outcome, as well as assess potential markers of breast CSCs for prognostic significance. Through the quantification of breast CSCs in primary breast tumours using in vivo xenografts assays we show that their presence correlates with aggressive tumour characteristics. In addition, we propose that markers of breast CSCs may differ based on the molecular subtype of the tumour, and that these markers have prognostic significance in patients. / Thesis / Master of Science (MSc)
507

Dietary intake, appetite and taste perceptions of cancer patients receiving chemotherapy and antiemetic treatment /

Latanick, Maureen Rogan January 1983 (has links)
No description available.
508

Breast Cancer and the Discourse of Risk

Simpson, Christy 06 1900 (has links)
This thesis explores the role of values in risk assessment for breast cancer. Why? First, breast cancer poses a serious health threat to women, yet currently has no known cause. This means the discussion of risk becomes central to this disease. Second, K.S. Shrader-Frechette has shown that values enter in at each stage of risk assessment. These stages are the choice of topics, methods, and evaluation. By using Shrader-Frechette's framework for analysis of such areas of breast cancer as mammography, prophylactic mastectomy, tamoxifen and the role of estrogen, research routes, and prevention, it can be shown that certain values dominate the risk assessment. These values are the technological imperative, individual causation of disease, and reductionism. This thesis argues that the dominance of these values has led to a narrow and biased view of breast cancer risk. This view leaves women with fewer legitimate choices for the management of breast cancer risk and in many ways excluded altogether from its risk discourse. As breast cancer advocacy groups have gained in strength, attention has been drawn to the fact that there are competing values which can be used in risk assessment for this disease. These competing values are a low-tech/high-preventative, holistic, care-oriented approach to disease. These values can provide a viable alternative assessment of risk in breast cancer. Furthermore, this alternative risk picture is more desirable than the current one, because it helps to redirect and widen the focus on risk in breast cancer and gives women a central role in its risk discourse. / Thesis / Master of Arts (MA)
509

Rôle de la consommation d'Anti-inflammatoires Non Stéroïdiens (AINS) dans la survenue du cancer de la prostate, du sein, et colorectal en France / Role of NSAIDs' Use in the Occurrence of Prostate, Breast and Colorectal Cancer in France

Doat, Solène 21 December 2017 (has links)
Contexte – Les cancers de la prostate, du sein, et colorectaux sont parmi les cancers les plus fréquents dans les pays développés, et, même si plusieurs facteurs de risque sont aujourd’hui bien établis pour ces cancers, leur étiologie reste encore largement à expliquer. L’inflammation chronique est fortement suspectée de jouer un rôle dans la survenue de ces cancers et la présence, dans les tissus tumoraux, d’infiltrats inflammatoires localisés pouvant être considérés comme des lésions précancéreuses, contribue à renforcer l’hypothèse d’un lien possible entre inflammation chronique et cancers. Dans ce contexte, de nombreuses études épidémiologiques se sont intéressées au rôle des Anti-Inflammatoires Non Stéroïdiens (AINS) dans les cancers. En effet, les médicaments ayant des propriétés anti-inflammatoires comme les AINS, dont l’aspirine, et les anti-inflammatoires inhibiteurs sélectifs de la cyclo-oxygénase 2 (COX-2), pourraient diminuer le risque de survenue de ces cancers.Objectifs – L’objectif général de cette thèse a été d’étudier le rôle de la consommation d’AINS, dont l’aspirine, les AINS usuels et les inhibiteurs sélectifs de la COX-2 dans la survenue des cancers de la prostate, du sein et colorectaux.Population et méthodes – Ce travail s’est appuyé sur les données de l’Echantillon Généraliste des Bénéficiaires (EGB) de l’Assurance Maladie pour les trois cancers d’intérêt et sur les données d’une étude cas-témoins réalisée en population générale dans le département de l’Hérault (EPICAP) pour le cancer de la prostate. Pour les données de l’EGB, une cohorte fixe de 426 410 personnes présentes au 1er janvier 2007 a permis d’identifier les cas incidents entre 2008 et 2012 à partir de différents algorithmes. L’exposition aux AINS a été identifiée à partir du 1er janvier 2005 jusqu’à la date de fin d’observation : date de survenue du cancer, date de décès ou date de censure fixée au 31 décembre 2012. Un temps de latence d’au moins un an a été défini entre l’exposition aux AINS et la survenue du cancer d’intérêt. Pour les données d’EPICAP, 819 cas incidents de cancer de la prostate et 879 témoins de population générale, de même âge en moyenne que les cas, ont été interrogés en face-à-face, à l’aide d’un questionnaire standardisé, notamment sur leur consommation d’AINS.Résultats – A partir de la cohorte issue de l’EGB, des résultats préliminaires montraient une augmentation du risque de cancer de la prostate (RR=1,30 [1,17-1,46]) et du sein (RR=1,29 [1,14-1,46]) chez les patients exposés aux AINS et une absence d’association pour les cancers colorectaux (RR=0,92 [0,82-1,05]). En revanche, une association négative était observée pour les cancers de la prostate (RR=0,85 [0,74-0,96]) et colorectaux (RR=0,77 [0,66-0,90]) lorsque le temps de latence considéré était de six ans. L’étude EPICAP a montré que la consommation d’AINS était associée négativement au cancer de la prostate (OR=0,77 [0,61-0,98]). Cette association était plus prononcée pour une fréquence de consommation quotidienne (OR=0,75 [0,33-0,92]) ou d’une consommation pluriquotidienne (OR=0,38 [0,18-0,79]), et pour une durée entre 5 à 10 ans (OR=0,55 [0,33-0,92]). L’association était renforcée pour une molécule ayant une activité anti-COX-2 préférentielle (OR=0,48 [0,28-0,79]). Enfin, une association négative était également observée pour les cancers de la prostate de haut grade (Gleason score =7 (4+3) ou GS>7) avec un OR de 0,62 [0,41-0,95].Conclusion – L’ensemble de ce travail de thèse a montré que la consommation d’AINS semblait être associée négativement à la survenue du cancer de la prostate et aux cancers colorectaux. Pour le cancer de la prostate cette thèse s’est appuyée sur deux bases de données et deux méthodologies différentes, permettant d’appréhender les limites et les forces de chacune. / Background – Prostate, breast, and colorectal cancers are among the most common cancers in developed countries. Many risk factors have been identified over the years but could explain only a part of the new cases. Chronic inflammation is highly suspected to play a role in the carcinogenesis of those cancers and the presence of inflammatory infiltrate in tumoral tissue, considered as precancerous lesions, reinforced this hypothesis. In this context, several epidemiological studies have investigated the potential role of Non-steroidal anti-inflammatory drugs (NSAIDs) in cancer occurrence. Indeed, NSAIDs such as aspirin and non-aspirin NSAIDS including selective inhibitors of cyclo-oxygenase 2 (COX-2) may decrease the incidence of those cancers.Objectives – The main objective of the thesis was to investigate the role of NSAIDs use including aspirin, non-aspirin NSAIDs and selective inhibitors of COX-2 in the occurrence of prostate, breast and colorectal cancers.Population and methods – This work was based on the General Sample of health insurance Beneficiaries (EGB) for the three localizations of cancer and on the data of a population-based case-control study carried out in the département of Herault (EPICAP) for prostate cancer. In the EGB study, a cohort of 426 410 persons present in the database in January 1st, 2007 allowed to identify incident cases between 2008 and 2012 based on different algorithms. Exposure to NSAIDs was determined from January 1st, 2005 until the end of the follow up defined as either cancer incident date, date of death, or censure date fixed as December 31st, 2012. A latency of at least one year between the beginning of exposure to NSAIDs and the cancer occurrence was taken into account. For the EPICAP study, 819 incident prostate cancer cases and 879 population-based controls, frequently matched by age to the cases, were face-to-face interviewed using a standardized questionnaire, specifically on their NSAIDs use.Results – From the EGB cohort, preliminary results showed a positive association between all NSAIDs use and prostate or breast cancer occurrence (RR=1,30 [1,17-1,46], RR=1,29 [1,14-1,46], respectively), while no association was found with colorectal cancer occurrence (RR=0,92 [0,82-1,05]). These associations became negative associations when a latency of six years was taken into account in prostate and colorectal cancer (RR=0,85[0,74-0,96], RR=0,77 [0,66-0,90], respectively). In the EPICAP study, NSAIDs use was negatively associated with prostate cancer (OR=0,77 [0,61-0,98]). This association was more pronounced with daily intake (OR=0,75 [0,33-0,92]) or more than once a day (OR=0,38 [0,18-0,79]), and for a duration of five to ten years (OR=0,55 [0,33-0,92]). The negative association was reinforced for preferential anti-COX-2 NSAIDs (OR=0,48 [0,28-0,79]), and for patient with high grade prostate cancer (Gleason score, GS=7 (4+3) or GS>7 : OR=0,62 [0,41-0,95]).Conclusion – This work showed that NSAIDs use was negatively to prostate and colorectal cancer occurrence. For prostate cancer, this thesis was based on two different databases (a medical and administrative database and a case-control study) and used two different methodologies, allowing comparison about strengths and limits of both.
510

Nucleotide sequence variation and expression levels of TP53 in cancers of the upper gastro-intestinal tract

Barnard, Desire 03 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: The work presented in this thesis deals with the association between cancers of the upper gastro-intestinal tract and the tumor suppressor gene, TP53, and can be divided into three parts: (i) the analysis of the mutational spectrum of TP53 with respect to laryngeal cancer, (ii) the analysis of the mutational spectrum of TP53 with respect to esophageal cancer and (iii) the analysis of TP53 transcriptional levels in esophageal cancer. Laryngeal cancer (LC) is the 6th most common cancer in the world and the 2nd most common respiratory cancer, with approximately 500 000 new cases per annum detected worldwide. Over the last few years, LC has become increasingly prevalent within the Coloured Community of the Western Cape. The mechanisms of tumorigenesis in LC remain unknown, although smoking and alcohol consumption are considered to be major risk factors. Mutations within the gene TP53 have been strongly implicated as playing a role in cancer development, as they are frequently found in several cancer types. We therefore screened exons 5 - 8 of TP53 for mutations in DNA from tumor biopsies (n=44) and blood samples (n=42) from Coloured LC patients, using polymerase chain reaction - single strand conformation polymorphism (PCR-SSCP) analysis and direct sequencing. Blood samples from a healthy, matched control group (n=40) were included in the study as controls. Significant correlations were found between the occurrence of LC and age and smoking, whereas daily meat consumption was a possible protective factor. In tumor-derived samples, mutations were found in 3 of the exons under investigation, representing 25% of the samples. The mutations were unique to the tumor biopsies, indicating a somatic origin for mutations. The data confirms that the region between codons 175 and 273 of TP53 is a mutational hotspot for cancers in general. This study reports 6 novel mutations within this same region. Esophageal cancer (EC) has a very high incidence in South Africa, relative to the rest of the world, and is particularly common amongst the Black Transkei population. The goal of this study was to determine whether there are differences in the TP53 mutational pattern observed in the Coloured Western Cape community as compared to that observed in the Black Transkei community. This required the analysis of the molecular structure of TP53, specifically exons 5 - 8, in a group of Coloured EC patients (n=44) treated at Tygerberg Hospital, Cape Town, South Africa. DNA obtained from tumor biopsies and blood (from patients) as well as from apparently healthy surrounding tissue was screened via PCR-SSCP and direct sequencing analysis. Only 4 nucleotide changes were observed from a total of 124 sequences obtained, of which two were novel to esophageal squamous cell carcinoma. These 4 nucleotide alterations were found only within the tumor biopsy sample set, representing 9% of the tumors investigated. This study revealed that the mutational spectrum of TP53 within the Coloured population of the Western Cape greatly differs from that of the Black community of the Transkei. This suggests that a different set of etiological factors are involved in the tumorigenic process for each of these distinct geographical communities, which is the subject of an epidemiological study undertaken by the MRC. The final part of this thesis deals with the quantification and comparison of TP53 transcription levels in esophageal cancer tumor tissue to the TP53 levels in healthy esophageal tissue obtained from patients from a unique geographical and ethnic background. The cohort used in this study consisted of Coloured patients (n=2) treated at Tygerberg Hospital. The LightCycler system was implemented in order to try to accurately quantify TP53 mRNA levels. Unfortunately, the desired results were unattainable due to unforeseen difficulties encountered during the study. These difficulties included the insufficient preservation of samples for RNA based studies. Several recommendations were made concerning future similar studies, including an improved planning strategy as well as the employment of an RNA stabilizing agent. Additionally, a few important contributions were made through this study, including the design and optimization of TP53 primers specifically intended for future RNA studies. These primers would enable the identification of the presence of TP53 RNA species as well as the absence of DNA contamination in a single PCR amplification step. Other contributions include the development of a well-optimized RNA extraction method for the extraction of RNA from tough tissues (such as the human esophageal tissue used in this study). This method makes the extraction of large quantities of RNA from small amounts of tough tissue types possible. In conclusion, this study has made a significant contribution to the field of cancer research, by shedding light on the TP53 mutational spectrum with regards to laryngeal as well as esophageal cancer in a population unique to the Western Cape. The first part of this thesis has been published in Cancer Genetics and Cytogenetics (Barnard, D., K. Lehmann, E.G. Haal, P.O. van Heiden, and l.C. Victor. 2003. The spectrum of mutations in TP53 in laryngeal cancer patients from a high-incidence population shows similarities to many of the known mutational hotspots. Cancer Genetics and Cytogenetics 145:126-132), of which a copy can be found in Appendix I. This work has also been presented (by D. Barnard) at an international conference entitled "Cancer of the Esophagus and Gastric Cardia: From Gene to Cure", held in Amsterdam, the Netherlands during the period 13 - 15 December 2002. / AFRIKAANSE OPSOMMING: Die werk wat in hierdie tesis voorgelê word handel oor die assosiasie tussen kankers van die boonste gastrointestinale weg en die tumor suppressor geen, TP53, en kan in 3 dele gedeel word, (i) die analise van die mutasiespektrum van TP53 in laringiale kanker (LK), (ii) die analise van die mutasiespektrum van TP53 in slukderm kanker (SK) en (iii) die analise van die transkripsievlakke van TP53 in SK. Laringeal kanker (LK) is die 6de algemeenste kanker in die wêreld en die 2de algemeenste respiratoriese kanker, met "n benaderde 500 000 nuwe gevalle jaarliks wêreldwyd. Oor die afgelope paar jare het LK "n toenemende probleem geraak, veral in die Kleurling gemeenskap van die Wes Kaap. Die meganismes van die tumorvorming in LK is onbekend, alhoewel rook-en alkoholgebruik vername risiko faktore is. Die voorkoms van mutasies in TP53 is verskeie kere aangetoon in verskillende kanker tipes en daar word vermoed dat dit "n rol speel in tumorvorming. In hierdie studie is dus na mutasies in eksons 5 - 8 van TP53 gesoek in tumor biopsie weefsel (n=44) en bloed isolate (n=42) van Kleurling LK pasiënte d.m.v. polimerase ketting reaksie - enkelstring konformasie polimorfisme (PKR-ESKP) analisering en direkte volgorde bepaling. Bloed monsters van "n vergelykbare groep (n=40) is ook in die studie ingesluit as "n kontrole. Betekenisvolle positiewe korrelasies is gevind tussen die voorkoms van LK en ouderdom sowel as rook. Daarmee saam is daaglikse vleisinname as potensiële beskermende faktor gevind. In tumor biopsies is mutasies in 3 van die ondersoekte eksons gevind, wat 25% van die biopsie monsters verteenwoordig. Hierdie mutasies is uniek aan die tumor biopsie weefsels en dui op "n somatiese oorsprong van mutasies. Hierdie bevindinge bevestig dat die gedeelte tussen kodons 173 - 273 van TP53 "n hipermuteerbare gebied geassosieer met kankers is. Hierdie studie bevestig 6 nuwe mutasies. Daar is 'n hoë insidensie van slukderm kanker (SK) in Suid Afrika relatief tot die res van die wêreld. Hierdie soort kanker word veral gevind by die Swart populasie van die Transkei. Die doel van hierdie studie was om verskille tussen die TP53 mutasie patroon van die Kleurling gemeenskap van die Wes Kaap en die Swart gemeenskap van die Transkei te vergelyk. Hiervoor is die molekulêre struktuur van TP53, veral eksons 5 - 8, in 'n groep Kleurling SK pasiënte (n=42) wat behandel is by Tygerberg Hospitaal, Kaapstad, Suid Afrika, geanaliseer. Analisering is gedoen deur DNS van tumor, bloed en ook oënskynlike gesonde aangrensende weefsel van dieselfde pasiënte te onderwerp aan PKR-ESKP analise en direkte volgorde bepaling. Slegs 4 nukleotied veranderings is gevind in 124 volgorde bepalings, waarvan 2 nuwe veranderings is in SK. Hierdie 4 nukleotied veranderinge verteenwoordig 9% van al die tumors wat ondersoek is in die studie. Hierdie studie bewys dat die mutasiespektrum van TP53 in die Kleurling gemeenskap van die Wes Kaap grootliks verskil van die Swart gemeenskap van die Transkei. Dit impliseer dat verskillende etiologiese faktore moontlik 'n rol mag speel op die tumorvormingsproses in die 2 afsonderlike geografiese gemeenskappe. Hierdie is die onderwerp van 'n epidemiologiese studie wat deur die MNR onderneem word. Die laaste deel van hierdie tesis handel oor die kwantifisering en vergelyking van TP53 transkripsievlakke in SK tumor weefsel teenoor TP53 vlakke in gesonde slukderm weefsel van pasiënte in 'n unieke geografiese en etniese agtergrond. Die studie populasie in hierdie projek het bestaan uit Kleurling pasiënte (n=2) wat by Tygerberg hospitaal behandel is. Die "LightCycler" sisteem is gebruik vir die akkurate kwantifisering van TP53 boodskapper RNS vlakke. Ongelukkig is die verlangde resultate nie gekry nie as gevolg van onvoorsiene probleme wat ondervind is tydens die studie. Hierdie probleme sluit in die onvoldoende preserv RNS studies. Hierdie inleiers maak dit nou moontlik om die teenwoordigheid van TP53 RNS spesies sowel as die afwesigheid van DNS kontaminasie in een PKR amplifikasie stap te kan identifiseer. 'n Ander belangrike bydrae is die ontwikkeling van 'n goed geoptimaliseerde RNS ekstraksie metode vir moeilike starre weelfsel tipes (soos menslike slukderm weefsel in hierdie studie) en maak die ekstraksie van groot hoeveelhede RNS uit klein hoeveelhede van moeilik hanteerbare weefsel tipes moontlik. Om saam te vat, hierdie studie het betekenisvolle bydraes gemaak tot die veld van kankernavorsing deur die ontrafeling van die TP53 mutasiespektrum in beide laringeale sowel as slukderm kanker, in 'n populasie uniek aan die Wes Kaap. Die eerste deel van hierdie tesis is gepubliseer in Cancer Geneties and Cytogenetics (Barnard, D., K. Lehmann, E. G. Hoal, P. D. van Heiden, and T. C. Victor. 2003. The spectrum of mutations in TP53 in laryngeal cancer patients from a high-incidence population shows similarites to many of the known mutational hotspots. Cancer Genetics and Cytogenetics 145: 126-132) en 'n afskrif van die artikel is ingesluit in Appendix I. Hierdie werk is ook voorgedra (deur D. Barnard) by 'n internasionale kongres getiteld "Cancer of the Esophagus and Gastric Cardia: From Gene to Cure", wat in Amsterdam, Nederland gehou is gedurende 13 - 15 Desember 2002

Page generated in 0.0527 seconds