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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.
271

The knowledge and practice of patients suffering from cancer of the breast about their disease at Princess Marina Hospital (PMH) Gaborone, Botswana

Mbuka-Ongona, Deogratias January 2009 (has links)
Thesis (M Med. (Family Medicine))-- University of Limpopo, 2009. / Introduction Inspired by the late presentation for care and consequently the diagnosis of breast cancer done at an advanced stage of the disease in majority of cases, this study aimed to explore the knowledge and practices related to breast cancer from patients presenting at Princess Marina Hospital (PMH) for care. Methodology The descriptive qualitative method using interviews (free attitude) was chosen to understand the trend of late presentation among participants, with following opening questions: 1. Can you please tell me all you know about the cancer of the breast? 2. How have you been treating your breast condition (growth/wound/pain) before you decided to come to PMH? Sampling was purposeful with a sample of twelve. Out of eleven interviews done with breast cancer patients fulfilling the criteria of inclusion, ten were used in the final analysis. Interviews were recorded (audiotape), transcribed verbatim and translated. Emerging themes were identified and coded into different categories Results This study noted a poor knowledge and understanding of patients about cancer of the breast. The knowledge and practice of the common well established screening methods like self breast examination (SBE) was equally poor. In majority, participants delayed going to the hospital as a result of the preceding( poor knowledge and understanding about Ca breast ), as well as the influence of lays beliefs and advices received from the surrounding. In some cases however advices from the surrounding resulted in timely medical consultation. Unexpectedly, Poor clinical practice of health worker in some cases and decision maker‟s inadequate involvement on issue of cancer awareness were other important themes which emerged during analysis of the results. Conclusions Cancer awareness together with consistent use of early detection measures by adhering to screening methods should be taken seriously and done throughout the country for the benefit of all potential victims, to address the poor knowledge, misconceptions and inappropriate health seeking behavior encountered in case of breast cancer.
272

Knowledge attitude and practice of breast cancer examination among women attending Extension 2 Clinic Gaborone, Botswana

Tiengo, Jane Gillead January 2010 (has links)
Thesis (MPH)--University of Limpopo, 2010. / Background: Screening for early detection and diagnosis of diseases and health conditions is an important public health principle. Breast cancer examination is whereby a woman will examine the breast by Breast Self Examination (BSE), Clinical Breast Examination (CBE), and Mammogram. Objective: The main aim of the study was to assess the knowledge, attitude and practice of breast cancer examination among women attending Extension 2 clinic in Gaborone, Botswana. Method: The cross-sectional quantitative study design to examine knowledge, attitude and practice of women attending Extension 2 clinic in Gaborone was carried out between August and September 2009 using an interviewer administered questionnaire designed by the researcher. Results: The study was conducted among 375 women attended at extension 2 clinic. Study participants had low knowledge of breast cancer examination. The overall mean knowledge score was 49.7%. The commonest presentation of breast cancer which is a painless breast lump only a third 128(34.1%) of the respondents knew about it. The participants had a positive attitude towards breast cancer examination. Practice of breast cancer examination was unacceptable. Out of 238 Of those who practiced breast self examination (63.5% ) (BSE), only 88(23.5%) of the respondents practiced monthly as required. Similarly only 85(22.7%) of the respondents had visited a doctor for clinical breast examination (CBE) in the past year. Mammogram practice was also unacceptable only 6 (1.6%) of the respondents had done mammogram in the past 2 years. There was no association between socio-demographic characteristics with the knowledge attitude and practice of breast cancer examination. Conclusion: The results of this study suggested that women attending at extension 2 clinic had low knowledge of breast cancer examination. Despite having positive attitude towards breast cancer examination, minority practiced breast self examination, clinical breast examination and mammogram. There was no association between socio-demographic characteristics with the knowledge of breast cancer. Therefore the Government should develop a policy on breast cancer screening. Awareness and advocacy campaign on breast cancer screening should be increased in the country.
273

Macrophages in Breast Cancer Progression

January 2017 (has links)
acase@tulane.edu / 1 / Emily Carron
274

Small angle x-ray scattering as a diagnostic tool for breast cancer

Sidhu, Sabeena January 2009 (has links)
Breast cancer is the most common cause of cancer death in Australian women. Current pathological analysis examines a small section of tissue for cellular and plasma abnormalities using a light microscope. However, this method of diagnosis, despite being the current gold standard, has its limitations, where human error and professional experience can influence a patient’s diagnosis. A potential alternative or adjunct to conventional histopathology for classifying tissue disease status is offered by Small Angle X-ray Scattering (SAXS). At the time of commencement of this work, there had been several small scale studies which examined the potential of SAXS to classify the disease status of breast tissue. These tended to focus on the supramolecular structure of collagen fibrils found in the breast, where it is known that the degradation of these fibres is related to the spread of disease. Most previous studies also used a synchrotron as an X-ray source, due to the intense and highly collimated flux available. This study used a synchrotron source, but also evaluated the use of a laboratory X-ray source, as a more convenient and relatively inexpensive alternative that could one day find application in the clinic. The work presented in this thesis analyses the largest cohort of patients and breast tissue samples studied to date using SAXS: 130 patients with 543 tissue samples. Tissues were sourced from surgical waste and classified into four groups: invasive carcinoma, benign, normal, and mammoplasty. Mammoplasty tissue samples were harvested from patients undergoing breast reduction and/or reconstruction, where no history or presence of disease was indicated. Normal tissue was sampled from patients with known disease, but pathological analysis of the tissue core diagnosed it as normal. A comprehensive analysis of the scattering patterns was carried out, analysing features arising from the collagen structure and orientation, the total scattered intensity, and adipose tissue in the breast. Features related to the axial D-spacing of the collagen fibrils within the breast tissue as well as the integrated scattering intensity (called amorphous scatter) demonstrated the highest ability to discriminate tissue types, in SAXS images acquired from both the synchrotron source and the laboratory X-ray source. The amorphous scatter intensities obtained using a synchrotron source showed highly significant differences (p < 0.01) for almost all of the tissue pair comparisons: invasive carcinoma vs. benign, invasive carcinoma vs. normal, invasive carcinoma vs. mammoplasty, benign vs. mammoplasty, and normal vs. mammoplasty. However, no significant difference was seen in the amorphous scatter between benign versus normal tissues (p = 0.30). The amorphous scatter values increased with severity of disease, i.e. it was the highest for invaded tissues and decreased progressively from benign to normal to mammoplasty. There was a significant difference between normal and mammoplasty tissue types using the amorphous scatter as a discriminator (p = 0.0025). Pathological assessment cannot differentiate between these two tissue types, which suggests that there may be changes occurring in these tissue structures at the supramolecular level that can be characterised using SAXS. The ability of SAXS to reveal structural differences between normal and mammoplasty tissue types is highly significant, for both disease diagnosis and treatment, as well as for understanding disease progression. For example, these differences might aid in determining surgical margin clearance of excised breast lesions as well as potentially provide a means of pre-screening or perhaps improve false-negative rates of diagnosis. The potential of SAXS to reveal macroscopic extent and directional spread of disease was explored using two-dimensional mapping of the amorphous scatter. These maps showed broad agreement with histopathological diagnosis, but further investigation regarding their reliability and interpretation for clinical utility is still needed. Changes in both the amorphous scatter and the axial D- spacing were seen in tissue samples up to 6 cm away from the primary site of disease. In particular, a significant decrease in both parameters was seen between the centre of the tumour (at 0 cm) and 2 cm away, suggesting that closer examination of the tissue structures over the disease/healthy tissue border may provide information regarding the mechanisms of metastasis and growth of cancerous tumours. The combination of the amorphous scattering results from the two X-ray sources indicates that the size of the scatterers may be the key in classifying tissue types. The synchrotron source was able to access a lower q-range (q = 0.1-0.6 nm-1) and the laboratory source covered a larger q-range (q = 0.25-2.3 nm-1). Mammoplasty tissues appear to be characterised by large scattering components (d > 25.13 nm), whereas normal tissues are characterised by slightly smaller scattering components (10.47 nm < d < 25.13 nm) and benign tissues by even smaller scattering components (4.83 < d < 10.47 nm). It appears that the size of the scatterers contributing to the total scattering intensity decreases with severity of disease, which was seen independently with both X-ray sources. Further investigation is warranted to determine the biological origin of these differences. These results also suggest that the optimum SAXS instrument may need to cover a scattering vector range of q < 0.25 nm-1 to identify differences in healthy tissue types, and q > 2.3 nm-1 to possibly investigate invasive carcinoma tissue types. A SAXS apparatus that can examine a large q-range may provide all of the necessary information from the amorphous scatter to differentiate between tissue groups. The periodic structure of collagen fibrils along their longitudinal axis can be characterised by the axial D-spacing, where this spacing was found to change with the presence of disease. The axial D-spacing for healthy breast tissues was found to be significantly lower in normal and mammoplasty tissues compared to invaded tissues (p = 0.0050 and p = 0.0093, respectively). However, no significant differences between the other tissue group pairs were seen (p > 0.05). These differences were evident in classification modelling of the four tissue groups, where the amorphous scatter and the amplitude of a collagen axial peak were used to build a probability model for disease status. The model showed high sensitivities (> 70%) and widely variable specificities (ranged from 18-97%) for the data examined with the synchrotron source. This means that the model was a good indicator of disease, but poor at indentifying healthy tissue types. The work presented in this thesis shows that SAXS is capable of distinguishing breast tissue types with high sensitivity and has the potential to become a significant tool for the investigation of cancer progression or even diagnosis. Further investigation into the amorphous scatter and axial D-spacing in particular may provide insight into the biological mechanisms related to tissue degradation associated with invasive disease.
275

Cell cycle control by ID1 and WT1 in breast cancer cells.

Caldon, Catherine Elizabeth, Garvan Institute of Medical Research, Faculty of Medicine, UNSW January 2007 (has links)
Loss of proliferative control is a cornerstone of cancer development, induced by deregulation of mitogenic signalling, insensitivity to anti-proliferative signals and direct changes in cell cycle proteins. In breast cancer these alterations are frequently targeted through cyclins D1 and E, leading to defects in G1/S transition. I have investigated the role of two potential pro-proliferative oncogenes in breast cancer, id1 andwt1. Each protein promotes proliferation in distinct contexts, with unique consquences for breast cancer cells. Using a 3D culture model of non-transformed mammary epithelial cells, I identified that id1 undergoes downregulation via rapid proteosomal degradation and cytoplasmic relocalisation during mammary epithelial morphogenesis. Overexpression of Id1 led to an increase in acinar size via an increase in S phase, and wa dependent on the presence of an intact HLH domain in Id1. Co-expression with the proto-oncogene Bcl2 led to a more disorganised acinar structure, indicating that Id1 overexpression primed the cells for further oncogenic insult. Further, Id1 overexpression was unable to increase acinar size in cyclin D1-/- acini, indicating that Id1 is dependent on cyclin D1 for its proliferative effects. Overall these data identified Id1 as capable of altering the proliferation of normal mammary epithelial cells, a crucial step in early breast carcinogenesis. Wt1 was originally identified as a tumour suppressor, but our data lends support to Wt1 acting as an oncogene in breast cancer. Wt1 is expressed highly in a range of breast cancer cell lines, and is strongly regulated by progestins. Using siRNA, we identified that Wt1 is likely to be a molecular intermediary of progestin as the downregulation of Wt1 mimics a subset of progestin effects on cell proliferation and lipid synthesis. Conversely, the overexpression of the major Wt1 isoform, Wt1 (+/+), led to attenuation of progestin-induced differentiation and growth arrest via maintenance of cyclin D1 levels. The effects of Wt1 overexpression were specific to progestins, and did not affect the actions of anti-estrogens or androgens. Consequently the overexpression of Wt1 (+/+) may disrupt the endocrine response in mammary epithelial cells, and contribute to excess proliferation and failure to differentiate during breast oncogenesis.
276

Surviving breast cancer a discourse analysis of breast cancer self-help groups

Bayers, Linda Sylvia January 2004 (has links)
Although there is a burgeoning canon addressing the detection, cause, treatment, and cure of breast cancer, there is a paucity of studies exploring how women survive the disruption and uncertainty breast cancer produces in their daily lives. There has been little exploration in the adult learning literature on the ways women might learn to live with breast cancer in the context of a heightened sense of mortality. Current institutional health education programs do not address the particular needs of individual women for practical and emotional support. In addition, the perspectives, resources, and knowledge of breast cancer self-help groups are not included in the literature on living with breast cancer. This study portrays survivor voices through the use of in-depth interviewing, participant observation, and document analysis. I use perspectives from feminist poststructuralism and Foucauldian discourse theory to explore the ways that the sixty-one women attending four breast cancer self-help groups in the late 1990s in urban and rural areas of Nova Scotia, Canada, learn to survive ? that is live with, through, and beyond ? breast cancer. While there was some variance in socioeconomic status and ethnicity, the participants were largely financially secure, married with children, of European descent, and between the ages of 33 and 83. This research shows that in their quest for survival, survivors moved amongst four overlapping discursive locations - the breast cancer self-help group, the family, the public sphere, and the cancer-care system with both support and conflict. Group discourses of reciprocity, self-care, temporality, and hope produce a range of discursive strategies for generating active survivor subjectivities. Through storytelling and the use of a powerful group technology, the survivor gaze, group members deconstruct the power technologies that disempower them. The analysis shows that survivors are active and resourceful in creating resistant, innovative, life-affirming, and self-respecting ways to speak themselves into social texts as authoritative and legitimate knowers, doers, and learners, producing new knowledge, resources, and truths about surviving. However, it is a major challenge for survivors to cope with the tense and contradictory effects of pervasive power and gender relations on the modes of subjectivities open to them. While masking of the postmastectomy body indicates that women are working on gendered identities, survivors are also learning to live their bodies in flux, taking up performative, cyborgian, productive, and playful bodies that challenge male-imposed definitions of what it is to be a woman, insisting on their right to define themselves. This thesis challenges the assumption that subjects must submit to the knowledge of experts in order to know, invent, and care for themselves. The research corroborates important insights from the self-help literature that self-help groups are significant social movements producing knowledgeable political subjects able to exercise power over their own lives. There is ample evidence that the expression and validation of emotions are central to knowledge construction processes. Further research is needed to examine how the knowledge produced by self-help groups can become officially recognized and utilized resources for survivors, and for those who care for and about them. / thesis (PhDEducation)--University of South Australia, 2004.
277

Bilateral breast cancer incidence and survival

McCaul, Kieran January 2006 (has links)
Introduction - This study re - examined the epidemiology of bilateral breast cancer with regard to the age at diagnosis and histology of the first breast cancer, and examined the effect of bilateral breast cancer on breast cancer survival. Methods - A cohort of US women with breast cancer was identified using cancer registry data for the period 1973 to 2000 obtained from the Surveillance, Epidemiology, and End Results ( SEER ) Program. In this cohort, incidence cases of bilateral breast cancer were identified and rates calculated per 1,000 person - years and the effect on survival of a diagnosis of a bilateral breast cancer was determined using time - dependent proportional hazard regression. Results - The overall incidence of bilateral breast cancer was 5.5 per 1,000 person - years and, apart from an elevation in incidence in the first year, was constant over time. In age - cohorts of young women, age - specific rates of bilateral breast cancer were found to decline as these women aged, approaching the incidence observed in older age cohorts. In older age - cohorts, age - specific rates were comparatively constant until age 75 - 79 years, after which age - specific rates began to decline regardless of age at first diagnosis.Differences in the crude incidence of bilateral breast cancer in sub - cohorts of women with lobular carcinoma ( 6.56 per 1,000 person - years ) and infiltrating ductal carcinoma ( 5.31 per 1,000 person - years ) were largely explained by differential incidence in the first year following diagnosis of the first breast cancer. Diagnosis of bilateral breast cancer increased the risk of breast cancer mortality, independent of the interval between the first and second breast cancer. Stage of both the first and second breast cancers was found to be the most important determinant of risk. Conclusions - This study found that the pattern of age - specific incidence of bilateral breast cancer was consistent with effects already well established in the literature describing the incidence of first primary breast cancer - pre - menopausal effects in young women and underascertainment in older women. Estimates of the incidence of bilateral breast cancer were subject to bias caused by an elevation in the incidence in the first year following diagnosis of the first breast cancer. This was most likely an effect of increased surveillance. This explained to a large extent, associations between the histology of the first breast cancer and the incidence of bilateral breast cancer observed in earlier studies. This study challenged the currently accepted view that bilateral breast cancer was a sign of increased susceptibility to breast cancer. Instead it is argued that the constant annual incidence of bilateral breast cancer suggests a final, discrete stage in a multistage carcinogenesis process. It is further argued that the observed incidence of bilateral breast cancer allows us to estimate the incidence of breast cancer in the population among women reaching this final stage within their lifetime. It is conservatively estimated that by age 75 to 79 years only half the women in the population have reached this final stage. This implies that in half the population of women, breast cancer either never initiates or progresses so slowly that the final stage of carcinogenesis is not reached within their lifetime. / Thesis (Ph.D.)--School of Population Health and Clinical Practice, 2006.
278

In vitro and in vivo characterization of the estrogen dependent human breast cancer cell line, MCF-7, over-expressing cyclooxygenase-2

Prosperi, Jenifer Robyn, January 2006 (has links)
Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 203-238).
279

Exploring Notch signaling pathways for breast cancer treatment

Han, Jianxun 11 1900 (has links)
Breast cancer is the most common cancer and the leading cause of cancer-related death among Canadian women. Despite improvements in treatment and early detection, there is still a need to develop novel therapies for breast cancer management. Aberrant Notch signaling is tumorigenic and is associated with poor clinical outcomes in breast cancer, as well as in several other types of cancer. Activation of Notch signaling requires -secretase-mediated Notch receptor cleavage. Thus, strategies to inhibit Notch signaling, including -secretase inhibition, are being evaluated for potential anti-tumor effects. The strongest justification for targeting Notch in breast cancer, and more specifically for using -secretase inhibitors, came from two studies that reported that the -secretase inhibitor (GSI) Z-LLNle-CHO inhibited the growth of breast cancer cells both in vitro and in vivo without causing significant side effects. In Chapter 2, we compared the enzymatic activities and cytotoxicity of Z-LLNle-CHO to those of two other specific GSIs and three proteasome inhibitors and demonstrated that the cytotoxicity of Z-LLNle-CHO in breast cancer cells is mediated by proteasome inhibition, not by -secretase inhibition. In Chapter 3, we characterized the protein complexes formed in breast cancer cells by the intracellular domains (NICD) of the four Notch paralogs. We found that the assembly of NICD protein complexes is dose-dependent and availability of MAML proteins becomes the limiting factor for continuous formation of NICD/RBPj/MAML transactivation complex. This suggests that the formation of some non-canonical NICD complex might occur preferentially at high levels of NICD, conditions under which aberrant Notch signaling induces tumorigenesis in breast cancer. Consequently, these non-canonical interactions might be good targets to specifically block oncogenic, but not physiological, Notch signaling. In addition, we found that the relative affinities of individual NICD paralogs to several known NICD-interacting proteins were different. This may account for the paralog-specific activities of Notch that have been previously reported. Together, these results may be of value for the development of new reagents to block Notch signaling for therapeutic benefit in breast cancer treatment. / Experimental Oncology
280

Role of estrogen receptor alpha (ER alpha) insulin-like growth factor (IGF)-I-induced responses in MCF-7 breast cancer cells

Zhang, Shu 15 May 2009 (has links)
Insulin-like growth factor-I (IGF-I) is a mitogenic polypeptide that induces proliferation and activation of kinase pathways in MCF-7 breast cancer cells. The role of estrogen receptor α (ERα) in mediating responses induced by IGF-I was investigated in cells transfected with small inhibitory RNA for ERα (iERα) or cotreated with the pure antiestrogen ICI 182780. The results showed that IGF-I-dependent phosphorylation of Akt and MAPK, induction of G1–S-phase progression and enhanced expression of cyclin D1 and cyclin E were dependent on ERα. Moreover, these IGF-I-induced responses were also inhibited by the antiestrogen ICI 182780, suggesting that the effects of ICI 182780 as an inhibitor of IGF-I induced responses in breast cancer cells are primarily related to downregulation of ERα. Chemoprotective phytochemicals exhibit multiple activities and interact with several cellular receptors, including the aryl hydrocarbon receptor (AhR). We investigated the AhR agonist/antagonist activities of the following flavonoids: chrysin, phloretin, kaempferol, galangin, naringenin, genistein, quercetin, myricetin, luteolin, baicalein, daidzein, apigenin, and diosmin, in MCF-7 breast cancer cells, HepG2 human liver cells and mouse Hepa-1 cells. The dietary phytochemicals exhibited substantial cell context–dependent AhR agonist as well as antagonist activities, and these are factors that must be considered in risk assessment of overall exposures to AhR agonists. Halogenated aromatic hydrocarbons (HAHs) such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 1,2,3,7,8- pentachlorodibenzo-p-dioxin (PeCDD), 3,3’,4,4’,5-pentachlorobiphenyl (PCBP), 2,3,7,8- tetrachlorodibenzofuran (TCDF) and 2,3,4,7,8-pentachlorodibenzofuran (PeCDF) bind and activate the aryl hydrocarbon receptor (AhR). It has been assumed that these compounds only differ in their potencies. The SAhRM-like activity of the 5 HAHs was investigated by determining ligand structure dependent differences in their induction of CYP1A1 and interactions of the AhR with a series of coactivators in a mammalian two-hybrid assay in three AhR-responsive cell lines, including mouse Hepa-1, Human HEK293 and human Panc1 cells. There were multiple structure-dependent differences in activation of luciferase activity in these cell lines transfected with VP-AhR and six different GAL4-coactivator chimeras and a GAL4-response element-luciferase promoter construct. The results show that HAHs selectively interact with coactivators and these interactions are dependent on cell-context, and even among HAHs, these compounds exhibit selective receptor modulator activity.

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