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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.
291

Cancer nanotechnology: engineering multifunctional nanostructures for targeting tumor cells and vasculatures

Kim, Gloria J. 06 April 2007 (has links)
Significant progress has been made in the development of new agents against cancer and new ways of delivering existing and new agents. Yet, the major challenge to target and selectively kill cancer cells while affecting as few healthy cells as possible remains. When linked with tumor targeting moieties such as tumor-specific ligands or monoclonal antibodies, nanoparticles can be used to target cancer-specific receptors, tumor biomarkers as well as tumor vasculatures with high affinity and precision. Recently, the use of nanoparticles for drug delivery and targeting has emerged as one of the most exciting and clinically important areas in cancer nanotechnology. In this work, we tested the hypothesis that our novel ternary biomolecular nanostructures of folic acid (FA), biodegradable polymer, and paclitaxel will improve the delivery and tumor-specific distribution of the anticancer drug. The design was based on three principles: 1) Passive targeting via enhanced permeation and retention (EPR) effect; 2) active targeting via a tumor-specific ligand; and 3) prodrug that would release the drug upon delivery. First, self-assembled polymer-paclitaxel-FA nanostructures were synthesized. Their physicochemical properties were examined and biological efficacy was tested. The conjugates had significantly improved solubility in water, enabling cremophor-free formulation. Second, in vitro cellular toxicity and targeting ability of the nanostructures were investigated. In cancer cell lines with high folate receptor (FR) expression, the ternary conjugates were efficiently taken up whereas no detectable association was found in cells with minimal or no FR expression. Third, in vivo investigation in human xenograft mice models was carried out. Ternary nanostructures drastically inhibited tumor growth without inducing systemic toxicity or side effects. The ternary nanostructures displayed remarkable anti-angiogenic effect on tumor vasculature. Heparin-paclitaxel-FA was also very effective in drug resistant tumors, potentially overcoming multidrug resistance. Studies in other cancer models are in progress to determine the spectrum of applicability of these ternary nanostructures. The design principles applied in these nanoparticles can be extended to delivery and targeting of diagnostic and imaging agents. The ability to engineer multifunctional nanostructures will have a significant impact on cancer diagnostics, molecular profiling, and the integration of cancer therapy and imaging.
292

Chemotherapy-induced mucositis : the role of gastrointestinal microflora and mucins in the luminal environment.

Stringer, Andrea M. January 2009 (has links)
Mucositis manifesting as diarrhoea is a common side effect of chemotherapy which remains poorly understood. It is one of a number of manifestations of alimentary mucositis, which affects the entire gastrointestinal tract. The exact number of patients that are affected by diarrhoea as a result of treatment is uncertain, although it is believed that approximately 10% of patients with advanced cancer will be afflicted. Despite advances in the understanding of oral and small intestinal mucositis over recent years, large intestinal mucositis, including diarrhoea, has not been well defined and the underlying mechanisms of the condition are yet to be established. The majority of the literature available concerning diarrhoea is based on clinical observations, with very little basic research existing. However, from the research conducted, it is likely that the intestinal microflora and mucins play a role in the development of chemotherapy-induced diarrhoea. This thesis will examine in detail what is known about the mechanisms of chemotherapy-induced diarrhoea (CID). Furthermore it will explore the potentially important relationship between intestinal microflora, the luminal environment and the subsequent development of chemotherapy-induced mucositis and diarrhoea. 5-Fluorouracil (5-FU) is a commonly used chemotherapy agent in clinical oncology practice. Two of its major side effects are mucositis and diarrhoea. The structure of mucins offers mucosal protection, and allows maintenance of intestinal flora by providing attachment sites and preventing bacterial overgrowth and/or penetration. Following treatment with 5-FU, we showed decreases in Clostridium spp., Lactobacillus spp. and Streptococcus spp., and an increase in Escherichia spp. in the jejunum. In the colon, 5-FU caused decreases in Enterococcus spp., Lactobacillus spp. and Streptococcus spp. Real time PCR of faecal samples showed decreasing trends in Lactobacillus spp. and Bacteroides spp., and an increasing trend in E. coli. Significant increases (p<0.05) were seen in Clostridium spp. and Staphylococcus spp. at 24 h. Goblet cell numbers decreased significantly in the jejunum from 24-72 h, with a significant increase in the percentage of cavitated goblet cells, suggesting 5-FU treatment causes significant changes in intestinal flora and mucin secretion in rats. These changes could result in systemic effects, and in particular may contribute to the development of chemotherapy-induced mucositis. Irinotecan causes cholinergic and delayed onset diarrhoea in patients, in which β-glucuronidase produced by gut bacteria is thought to be involved. Diarrhoea was observed in treated rats, as expected, following irinotecan treatment. β-glucuronidase expression increased in the jejunum and colon. Faecal flora changed quantitatively after treatment also, with increases in E. coli, Staphylococcus spp., and Clostridium spp. (all β-glucuronidase producing), and decreases in Lactobacillus spp., Bifidobacterium spp. (both beneficial bacteria), and Bacteroides spp. (β-glucuronidase producing, major component of intestinal flora), suggesting that irinotecan-induced diarrhoea may be caused by an increase in β-glucuronidase producing bacteria. However, the increase in bacteria may also be caused by irinotecan, further exaggerating the toxicity of the drug, and emphasising the need for these specific bacteria to be therapeutically targeted for successful treatment regimens to be accomplished. Mucus production appears to be increased after irinotecan treatment, which may contribute to the development of diarrhoea. Goblet cells were demonstrated to decrease significantly after irinotecan treatment. However, mucin secretion increased. Mucin expression changed significantly after treatment. Muc2 and Muc4 decreased significantly in the villi of the jejunum after treatment, Muc2 and Muc4 decreased significantly in the crypts. Muc2 decreased significantly in the colon. This indicates that irinotecan causes an increase in mucin secretion and a net decrease in mucin-producing goblet cells, and the expression of Muc2 and Muc4 in the gastrointestinal tract is altered following treatment. Increased mucin secretion is likely to be related to altered mucin expression, and may contribute to chemotherapy-induced diarrhoea. To determine if the changes to the intestinal microflora caused by chemotherapy could be translated to the clinic, a pilot clinical study was carried out. Sixteen patients experiencing CID were recruited to the study with two control subjects. A large proportion of patients (75%) demonstrated a reduced anaerobic component of their faecal microflora. A reduced diversity of species was also observed in patients. The majority of patients exhibited decreases in Clostridium spp., Lactobacillus spp. and Bifidobacterium spp., whilst all patients exhibited decreases in Bacteroides spp. and Enterococcus spp. Patients receiving antibiotics did not exhibit any marked differences to patients not receiving antibiotics. This indicates that the results observed in the animal studies are clinically relevant, and further research into this area should be undertaken. CID is associated with marked changes in the intestinal microflora. These changes may result in diminished bacterial functions within the gut, altering gut function and initiating intestinal damage, resulting in the onset of diarrhoea. In conclusion, there is clear evidence demonstrating chemotherapy treatment results in changes to the intestinal microflora and mucin secretion, which may be responsible in part for the development of severe mucositis and diarrhoea. Irinotecan toxicity may be compounded by the increase in β-glucuronidase producing bacteria. The intestinal flora of cancer patients experiencing CID is also noticeably different to that of healthy subjects. Irinotecan causes changes to mucin secretion, and the specific expression of Muc2, Muc4 and Klf4, suggesting that secretory control by the enteric nervous system may also be affected by chemotherapy. This research has extended the understanding of chemotherapy-induced mucositis and diarrhoea, complex side effects of chemotherapy. However, new areas for future research have also been identified. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1352119 / Thesis (Ph.D.) - University of Adelaide, School of Medicine, 2009
293

Chemotherapy-induced mucositis : the role of gastrointestinal microflora and mucins in the luminal environment.

Stringer, Andrea M. January 2009 (has links)
Mucositis manifesting as diarrhoea is a common side effect of chemotherapy which remains poorly understood. It is one of a number of manifestations of alimentary mucositis, which affects the entire gastrointestinal tract. The exact number of patients that are affected by diarrhoea as a result of treatment is uncertain, although it is believed that approximately 10% of patients with advanced cancer will be afflicted. Despite advances in the understanding of oral and small intestinal mucositis over recent years, large intestinal mucositis, including diarrhoea, has not been well defined and the underlying mechanisms of the condition are yet to be established. The majority of the literature available concerning diarrhoea is based on clinical observations, with very little basic research existing. However, from the research conducted, it is likely that the intestinal microflora and mucins play a role in the development of chemotherapy-induced diarrhoea. This thesis will examine in detail what is known about the mechanisms of chemotherapy-induced diarrhoea (CID). Furthermore it will explore the potentially important relationship between intestinal microflora, the luminal environment and the subsequent development of chemotherapy-induced mucositis and diarrhoea. 5-Fluorouracil (5-FU) is a commonly used chemotherapy agent in clinical oncology practice. Two of its major side effects are mucositis and diarrhoea. The structure of mucins offers mucosal protection, and allows maintenance of intestinal flora by providing attachment sites and preventing bacterial overgrowth and/or penetration. Following treatment with 5-FU, we showed decreases in Clostridium spp., Lactobacillus spp. and Streptococcus spp., and an increase in Escherichia spp. in the jejunum. In the colon, 5-FU caused decreases in Enterococcus spp., Lactobacillus spp. and Streptococcus spp. Real time PCR of faecal samples showed decreasing trends in Lactobacillus spp. and Bacteroides spp., and an increasing trend in E. coli. Significant increases (p<0.05) were seen in Clostridium spp. and Staphylococcus spp. at 24 h. Goblet cell numbers decreased significantly in the jejunum from 24-72 h, with a significant increase in the percentage of cavitated goblet cells, suggesting 5-FU treatment causes significant changes in intestinal flora and mucin secretion in rats. These changes could result in systemic effects, and in particular may contribute to the development of chemotherapy-induced mucositis. Irinotecan causes cholinergic and delayed onset diarrhoea in patients, in which β-glucuronidase produced by gut bacteria is thought to be involved. Diarrhoea was observed in treated rats, as expected, following irinotecan treatment. β-glucuronidase expression increased in the jejunum and colon. Faecal flora changed quantitatively after treatment also, with increases in E. coli, Staphylococcus spp., and Clostridium spp. (all β-glucuronidase producing), and decreases in Lactobacillus spp., Bifidobacterium spp. (both beneficial bacteria), and Bacteroides spp. (β-glucuronidase producing, major component of intestinal flora), suggesting that irinotecan-induced diarrhoea may be caused by an increase in β-glucuronidase producing bacteria. However, the increase in bacteria may also be caused by irinotecan, further exaggerating the toxicity of the drug, and emphasising the need for these specific bacteria to be therapeutically targeted for successful treatment regimens to be accomplished. Mucus production appears to be increased after irinotecan treatment, which may contribute to the development of diarrhoea. Goblet cells were demonstrated to decrease significantly after irinotecan treatment. However, mucin secretion increased. Mucin expression changed significantly after treatment. Muc2 and Muc4 decreased significantly in the villi of the jejunum after treatment, Muc2 and Muc4 decreased significantly in the crypts. Muc2 decreased significantly in the colon. This indicates that irinotecan causes an increase in mucin secretion and a net decrease in mucin-producing goblet cells, and the expression of Muc2 and Muc4 in the gastrointestinal tract is altered following treatment. Increased mucin secretion is likely to be related to altered mucin expression, and may contribute to chemotherapy-induced diarrhoea. To determine if the changes to the intestinal microflora caused by chemotherapy could be translated to the clinic, a pilot clinical study was carried out. Sixteen patients experiencing CID were recruited to the study with two control subjects. A large proportion of patients (75%) demonstrated a reduced anaerobic component of their faecal microflora. A reduced diversity of species was also observed in patients. The majority of patients exhibited decreases in Clostridium spp., Lactobacillus spp. and Bifidobacterium spp., whilst all patients exhibited decreases in Bacteroides spp. and Enterococcus spp. Patients receiving antibiotics did not exhibit any marked differences to patients not receiving antibiotics. This indicates that the results observed in the animal studies are clinically relevant, and further research into this area should be undertaken. CID is associated with marked changes in the intestinal microflora. These changes may result in diminished bacterial functions within the gut, altering gut function and initiating intestinal damage, resulting in the onset of diarrhoea. In conclusion, there is clear evidence demonstrating chemotherapy treatment results in changes to the intestinal microflora and mucin secretion, which may be responsible in part for the development of severe mucositis and diarrhoea. Irinotecan toxicity may be compounded by the increase in β-glucuronidase producing bacteria. The intestinal flora of cancer patients experiencing CID is also noticeably different to that of healthy subjects. Irinotecan causes changes to mucin secretion, and the specific expression of Muc2, Muc4 and Klf4, suggesting that secretory control by the enteric nervous system may also be affected by chemotherapy. This research has extended the understanding of chemotherapy-induced mucositis and diarrhoea, complex side effects of chemotherapy. However, new areas for future research have also been identified. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1352119 / Thesis (Ph.D.) - University of Adelaide, School of Medicine, 2009
294

Chemotherapy-induced mucositis : the role of gastrointestinal microflora and mucins in the luminal environment.

Stringer, Andrea M. January 2009 (has links)
Mucositis manifesting as diarrhoea is a common side effect of chemotherapy which remains poorly understood. It is one of a number of manifestations of alimentary mucositis, which affects the entire gastrointestinal tract. The exact number of patients that are affected by diarrhoea as a result of treatment is uncertain, although it is believed that approximately 10% of patients with advanced cancer will be afflicted. Despite advances in the understanding of oral and small intestinal mucositis over recent years, large intestinal mucositis, including diarrhoea, has not been well defined and the underlying mechanisms of the condition are yet to be established. The majority of the literature available concerning diarrhoea is based on clinical observations, with very little basic research existing. However, from the research conducted, it is likely that the intestinal microflora and mucins play a role in the development of chemotherapy-induced diarrhoea. This thesis will examine in detail what is known about the mechanisms of chemotherapy-induced diarrhoea (CID). Furthermore it will explore the potentially important relationship between intestinal microflora, the luminal environment and the subsequent development of chemotherapy-induced mucositis and diarrhoea. 5-Fluorouracil (5-FU) is a commonly used chemotherapy agent in clinical oncology practice. Two of its major side effects are mucositis and diarrhoea. The structure of mucins offers mucosal protection, and allows maintenance of intestinal flora by providing attachment sites and preventing bacterial overgrowth and/or penetration. Following treatment with 5-FU, we showed decreases in Clostridium spp., Lactobacillus spp. and Streptococcus spp., and an increase in Escherichia spp. in the jejunum. In the colon, 5-FU caused decreases in Enterococcus spp., Lactobacillus spp. and Streptococcus spp. Real time PCR of faecal samples showed decreasing trends in Lactobacillus spp. and Bacteroides spp., and an increasing trend in E. coli. Significant increases (p<0.05) were seen in Clostridium spp. and Staphylococcus spp. at 24 h. Goblet cell numbers decreased significantly in the jejunum from 24-72 h, with a significant increase in the percentage of cavitated goblet cells, suggesting 5-FU treatment causes significant changes in intestinal flora and mucin secretion in rats. These changes could result in systemic effects, and in particular may contribute to the development of chemotherapy-induced mucositis. Irinotecan causes cholinergic and delayed onset diarrhoea in patients, in which β-glucuronidase produced by gut bacteria is thought to be involved. Diarrhoea was observed in treated rats, as expected, following irinotecan treatment. β-glucuronidase expression increased in the jejunum and colon. Faecal flora changed quantitatively after treatment also, with increases in E. coli, Staphylococcus spp., and Clostridium spp. (all β-glucuronidase producing), and decreases in Lactobacillus spp., Bifidobacterium spp. (both beneficial bacteria), and Bacteroides spp. (β-glucuronidase producing, major component of intestinal flora), suggesting that irinotecan-induced diarrhoea may be caused by an increase in β-glucuronidase producing bacteria. However, the increase in bacteria may also be caused by irinotecan, further exaggerating the toxicity of the drug, and emphasising the need for these specific bacteria to be therapeutically targeted for successful treatment regimens to be accomplished. Mucus production appears to be increased after irinotecan treatment, which may contribute to the development of diarrhoea. Goblet cells were demonstrated to decrease significantly after irinotecan treatment. However, mucin secretion increased. Mucin expression changed significantly after treatment. Muc2 and Muc4 decreased significantly in the villi of the jejunum after treatment, Muc2 and Muc4 decreased significantly in the crypts. Muc2 decreased significantly in the colon. This indicates that irinotecan causes an increase in mucin secretion and a net decrease in mucin-producing goblet cells, and the expression of Muc2 and Muc4 in the gastrointestinal tract is altered following treatment. Increased mucin secretion is likely to be related to altered mucin expression, and may contribute to chemotherapy-induced diarrhoea. To determine if the changes to the intestinal microflora caused by chemotherapy could be translated to the clinic, a pilot clinical study was carried out. Sixteen patients experiencing CID were recruited to the study with two control subjects. A large proportion of patients (75%) demonstrated a reduced anaerobic component of their faecal microflora. A reduced diversity of species was also observed in patients. The majority of patients exhibited decreases in Clostridium spp., Lactobacillus spp. and Bifidobacterium spp., whilst all patients exhibited decreases in Bacteroides spp. and Enterococcus spp. Patients receiving antibiotics did not exhibit any marked differences to patients not receiving antibiotics. This indicates that the results observed in the animal studies are clinically relevant, and further research into this area should be undertaken. CID is associated with marked changes in the intestinal microflora. These changes may result in diminished bacterial functions within the gut, altering gut function and initiating intestinal damage, resulting in the onset of diarrhoea. In conclusion, there is clear evidence demonstrating chemotherapy treatment results in changes to the intestinal microflora and mucin secretion, which may be responsible in part for the development of severe mucositis and diarrhoea. Irinotecan toxicity may be compounded by the increase in β-glucuronidase producing bacteria. The intestinal flora of cancer patients experiencing CID is also noticeably different to that of healthy subjects. Irinotecan causes changes to mucin secretion, and the specific expression of Muc2, Muc4 and Klf4, suggesting that secretory control by the enteric nervous system may also be affected by chemotherapy. This research has extended the understanding of chemotherapy-induced mucositis and diarrhoea, complex side effects of chemotherapy. However, new areas for future research have also been identified. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1352119 / Thesis (Ph.D.) - University of Adelaide, School of Medicine, 2009
295

Cancer care services in Greece : a Delphi approach to investigate the views of healthcare providers and users

Efstathiou, Nikolaos January 2004 (has links)
Cancer is emerging as a major problem globally and effective cancer care services are needed to lessen its burden on the community. In Greece, oncology health service provision is not located efficiently, resulting in only few patients receiving high quality care. Furthermore, shortages of health professionals and underdeveloped services such as primary care, home care and palliative care in the Greek NHS have aggravated the problem. The limited resources for healthcare have led to the absence of a national cancer registry, thus the extent of cancer incidence cannot be evaluated effectively. The dissatisfaction of the population regarding the Greek NHS is well established, despite the numerous reforms proposed by consecutive Greek governments. It remains that limited research exists in the area of oncology, especially on cancer services and cancer care. The aim of this study was to identify the key areas of cancer care and services that needed to be developed or improved in Greece and their prioritisation within the Greek healthcare system. Once identified, these areas of improvement could be used in a policy making context for the provision of effective services to cancer patients and might provide areas for further research A new Delphi technique (Q-Delphi) was introduced as an extension of the classical Delphi and implemented in two settings to collect data from a sample of 30 healthcare providers and 30 healthcare users. This was to reduce the potential subjectivity that may be introduced by the researcher in generating themes as an essential part of a successful Delphi outcome. The Q-Delphi of healthcare providers consisted of three rounds while that of the healthcare users was based on two rounds. The response rates for all rounds in both Q-Delphi studies were over 77%. The priorities for healthcare providers were focused on staff shortages, working conditions, pain management, home care, day units and communication. Healthcare users' highest priorities included the provision of and research on effective treatment, lessening the financial costs involved and the organisation of cancer services. Despite the separate Delphi studies, there were areas that both healthcare providers and users identified and prioritised. However, for the areas that both panels shared, there was a significant difference between their prioritisation. The World Health Organisation (WHO) suggestions for controlling cancer were used to triangulate, explain and discuss the results from this study (WHO 2002). The areas identified by healthcare providers and users were within those recommended by WHO. Based on the priorities provided by the participants and the suggestions by WHO, the establishment of a national cancer registry, the employment of nurses in order to develop primary care, home care, day care and palliative care services, education in communication skills and redistribution of the bio-medical technology are recommended in order to reduce the burden of cancer hi Greece. More research is needed to validate the actual level of cancer services provided in Greece. In addition, Q-Delphi is suggested as a valid and objective research method. For the benefit of Greek researchers, copies of documents used in conducting the research are also presented in Greek (Appendices 3 to 13 and 15).
296

[en] SYNTHESIS AND CHARACTERIZATION OF COMPOUNDS FORMED BETWEEN CISPLATINUM AND GLUTATHIONE OR PENICILLAMINE LIGANDS / [pt] SÍNTESE E CARACTERIZAÇÃO DE COMPOSTOS FORMADOS ENTRE A CISPLATINA E OS LIGANTES GLUTATIONA OU PENICILAMINA

LEONARDO VIANA DE FREITAS 30 August 2010 (has links)
[pt] A cisplatina é um dos mais importantes agentes quimioterápicos usados no tratamento de diversos tipos de câncer. Entretanto, seu uso ocasiona efeitos colaterais, como ototoxicidade, neurotoxicidade e, em especial, a nefrotoxicidade, que é um dos mais significativos. Isso tem sido relacionado à interação da cisplatina com biomoléculas sulfuradas, como proteínas e aminoácidos. De modo a reduzir esses efeitos, tem-se sugerido a co-administração de certos compostos químicos sulfurados, denominados agentes salvadores, junto à cisplatina, o que poderia impedir sua interação com as moléculas sulfuradas no organismo e, por sua vez, a redução dos efeitos colaterais. Dentre esses agentes, sugere-se o tripeptídeo glutationa e o aminoácido penicilamina. A glutationa é o principal agente desintoxicante e antioxidante do organismo, sendo indispensável à homeostase celular, e a penicilamina é utilizada como medicamento no tratamento da doença de Wilson e artrite reumatoide. Dessa forma, visou-se, com este trabalho, a síntese e caracterização de dois complexos entre a cisplatina e os mesmos. A partir das técnicas de caracterização, que foram análise elementar, análise termogravimétrica e espectroscopias no infravermelho e Raman, foi possível sugerir uma estrutura para cada um dos complexos em que os ligantes se comportam de forma monodentada, sendo o enxofre o átomo doador. Isso ratificou o que é predito pelo conceito de ácidos e bases duros e macios, que comenta que ácidos de Lewis macios, que é o caso de Pt(2+) presente na cisplatina, têm grande afinidade química por bases de Lewis macias, que é o caso do enxofre presente no grupo tiolato dos ligantes desprotonados. O uso de cálculos teóricos, baseados nas estruturas propostas, como uma técnica recurso complementar de caracterização, foi de grande utilidade, já que, através dos mesmos, foi possível atribuir com maior segurança certas bandas presentes nos espectros de infravermelho e Raman experimentais. / [en] Cisplatinum is considered an important chemotherapeutic drug used against some kinds of cancer. However, the use of this drug may cause side effects such as ototoxicity, neurotoxicity and, mainly, nephrotoxicity. This fact has been related to the interaction of cisplatinum with biomolecules containing sulfur, such as proteins and amino acids. To promote the reduction of these effects, the coadministration of some compounds, called rescue agents, has been suggested in an attempt to prevent the interaction between cisplatinum and those biomolecules. Glutathione, a tripeptide, and the amino acid penicillamine could be used for this purpose. The former is the most important antioxidant in the human body and acts in cell homeostasis, and the latter is used in the treatment of Wilson’s disease and rheumatoid arthritis. Thus, considering the possibilities of interaction between cisplatinum and these sulfur agents, this work intended to synthesize and characterize the compounds formed by them. Using characterization techniques such as elementary analysis, thermogravimetry, and infrared and Raman spectroscopies, it was possible to suggest the structure of each compound, in which the ligands behaved as monodentate, bounding through the sulfur atom. This agree with the theory of soft and hard acids and bases, which predicts the affinity between platinum (Lewis acid) and sulfur (Lewis base). The use of theoretical calculations based on the structures proposed was very useful because it was possible to attribute some bands in the infrared and Raman spectra with more certainty.
297

Caracterização dos mecanismos de ação da imunoterapia intravesical com P-MAPA envolvendo as vias de sinalização dor receptores Toll-like (TLR) 2 e 4 na progressão do câncer de bexiga não-músculo invasivo

Rocha, Ana Beatriz Missio Vieira da [UNESP] 17 April 2015 (has links) (PDF)
Made available in DSpace on 2015-08-20T17:10:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-04-17. Added 1 bitstream(s) on 2015-08-20T17:26:56Z : No. of bitstreams: 1 000840998_20151016.pdf: 568585 bytes, checksum: e8f035e4f942fd75fc6ad38083a8fd0d (MD5) Bitstreams deleted on 2015-10-16T13:54:07Z: 000840998_20151016.pdf,. Added 1 bitstream(s) on 2015-10-16T13:54:48Z : No. of bitstreams: 1 000840998.pdf: 3047380 bytes, checksum: 4f011bacf1f109d530d0cddd6178474e (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Agonistas dos receptores Toll-like (TLRs) podem representar candidatos promissores a serem desenvolvidos como medicamentos contra o câncer. Atualmente, a terapia mais eficaz para o câncer de bexiga urinária não-músculo invasivo (CBNMI) é a imunoterapia com BCG (Bacillus Calmette-Guerin), embora sua utilização esteja limitada a efeitos colaterais de intensidades variadas. Diante deste cenário destaca-se o P-MAPA, que por sua grande versatilidade e mínima citoxicidade, abre uma nova perspectiva para o combate de alguns tipos de cânceres, incluindo o CBNMI. Assim, os objetivos principais deste estudo foram caracterizar os efeitos histopatológicos e moleculares da imunoterapia intravesical com P-MAPA envolvendo as vias de sinalização dos TLRs 2 e 4 no tratamento do CBNMI induzido quimicamente em camundongos selvagens (wild type - WT) e knockouts (-/-) para TLR4 e MyD88. Os efeitos da imunoterapia com P-MAPA foram comparados com o tratamento com BCG. Foram utilizados 20 camundongos fêmeas de cada linhagem (WT, TLR4-/- e MyD88-/-), todos com 60 dias de idade e mantidos no Centro de Medicina Nuclear da Faculdade de Medicina/USP - São Paulo. Os animais foram divididos em 4 grupos de 5 animais, para cada linhagem: Grupo Controle (CTL): recebeu uma dose intravesical de solução fisiológica por 3 semanas consecutivas; Grupo MNU: recebeu uma dose intravesical de N-metil-N-nitrosouréia (MNU) a cada 15 dias, totalizando 3 doses; Grupo MNU+BCG: recebeu uma dose intravesical de BCG por 3 semanas consecutivas; Grupo MNU+P-MAPA: recebeu uma dose intravesical de P-MAPA por 3 semanas consecutivas. Após 09 semanas de experimento, as bexigas urinárias foram coletadas e submetidas às análises histopatológicas e Western Blotting. O presente trabalho demonstrou que a imunoterapia com P-MAPA promoveu distinta ativação do sistema imune inato mediada por TLRs 2 e 4 em relação ao BCG, resultando no aumento da via de sinalização para... / Compounds that are able to act as Toll-like receptors (TLRs) agonists may represent promising candidates to be developed as drugs against cancer. Currently, the most effective therapy for non-muscle invasive bladder cancer (NMIBC) is immunotherapy with BCG (Bacillus Calmette-Guerin) associated with transurethral resection. However, the use of BCG is associated with side effects of varying strengths and in this scenario highlights the P-MAPA, which in great versatility and minimal cytotoxicity, opens a new perspective for fighting certain types of cancers, including NMIBC. Thus, the main objectives of this study were to characterize the histopathological and molecular effects of intravesical immunotherapy with P-MAPA involving the signaling pathways of TLRs 2 and TLR4 in the NMIBC treatment chemically induced in Wild Type mice (Wild Type - WT) and knockouts (-/-) for TLR4 and MyD88. The effects of P-MAPA immunotherapy were compared with BCG treatment. It were utilized 20 female mice of each strain (WT, TLR4 -/- and MyD88 -/-), all with 60 days of age and kept in the Nuclear Medicine Center, School of Medicine / USP - São Paulo. The animals were divided into 4 groups of 5 animals for each strain: Control Group (CTL): received intravesical dose of saline for 3 consecutive weeks; MNU Group: received a intravesical dose of N-methyl-N-Nitrosourea (MNU) every 15 days, a total of 3 doses; MNU+BCG Group: received received intravesical dose of BCG for 3 consecutive weeks; MNU+P-MAPA Group: received intravesical dose of P-MAPA for 3 consecutive weeks. After 09 weeks of experiment, urinary bladders were collected and submitted to histopathological and Western blotting analysis. The present study showed that P-MAPA immunotherapy led to distinct activation of the innate immune system TLR2 and 4-mediated when compared to BCG, resulting in increased signaling pathway for interferon (TRIF, IRF3, IFN-α and IFN-γ ) and restoration of the p53 protein ...
298

Caracterização dos mecanismos de ação da imunoterapia intravesical com P-MAPA envolvendo as vias de sinalização dor receptores Toll-like (TLR) 2 e 4 na progressão do câncer de bexiga não-músculo invasivo /

Rocha, Ana Beatriz Missio Vieira da. January 2014 (has links)
Orientador: Wagner José Fávaro / Banca: Cintia Yuri Matsumura / Banca: Flávio de Oliveira Lima / Resumo: Agonistas dos receptores Toll-like (TLRs) podem representar candidatos promissores a serem desenvolvidos como medicamentos contra o câncer. Atualmente, a terapia mais eficaz para o câncer de bexiga urinária não-músculo invasivo (CBNMI) é a imunoterapia com BCG (Bacillus Calmette-Guerin), embora sua utilização esteja limitada a efeitos colaterais de intensidades variadas. Diante deste cenário destaca-se o P-MAPA, que por sua grande versatilidade e mínima citoxicidade, abre uma nova perspectiva para o combate de alguns tipos de cânceres, incluindo o CBNMI. Assim, os objetivos principais deste estudo foram caracterizar os efeitos histopatológicos e moleculares da imunoterapia intravesical com P-MAPA envolvendo as vias de sinalização dos TLRs 2 e 4 no tratamento do CBNMI induzido quimicamente em camundongos selvagens (wild type - WT) e knockouts (-/-) para TLR4 e MyD88. Os efeitos da imunoterapia com P-MAPA foram comparados com o tratamento com BCG. Foram utilizados 20 camundongos fêmeas de cada linhagem (WT, TLR4-/- e MyD88-/-), todos com 60 dias de idade e mantidos no Centro de Medicina Nuclear da Faculdade de Medicina/USP - São Paulo. Os animais foram divididos em 4 grupos de 5 animais, para cada linhagem: Grupo Controle (CTL): recebeu uma dose intravesical de solução fisiológica por 3 semanas consecutivas; Grupo MNU: recebeu uma dose intravesical de N-metil-N-nitrosouréia (MNU) a cada 15 dias, totalizando 3 doses; Grupo MNU+BCG: recebeu uma dose intravesical de BCG por 3 semanas consecutivas; Grupo MNU+P-MAPA: recebeu uma dose intravesical de P-MAPA por 3 semanas consecutivas. Após 09 semanas de experimento, as bexigas urinárias foram coletadas e submetidas às análises histopatológicas e Western Blotting. O presente trabalho demonstrou que a imunoterapia com P-MAPA promoveu distinta ativação do sistema imune inato mediada por TLRs 2 e 4 em relação ao BCG, resultando no aumento da via de sinalização para... / Abstract: Compounds that are able to act as Toll-like receptors (TLRs) agonists may represent promising candidates to be developed as drugs against cancer. Currently, the most effective therapy for non-muscle invasive bladder cancer (NMIBC) is immunotherapy with BCG (Bacillus Calmette-Guerin) associated with transurethral resection. However, the use of BCG is associated with side effects of varying strengths and in this scenario highlights the P-MAPA, which in great versatility and minimal cytotoxicity, opens a new perspective for fighting certain types of cancers, including NMIBC. Thus, the main objectives of this study were to characterize the histopathological and molecular effects of intravesical immunotherapy with P-MAPA involving the signaling pathways of TLRs 2 and TLR4 in the NMIBC treatment chemically induced in Wild Type mice (Wild Type - WT) and knockouts (-/-) for TLR4 and MyD88. The effects of P-MAPA immunotherapy were compared with BCG treatment. It were utilized 20 female mice of each strain (WT, TLR4 -/- and MyD88 -/-), all with 60 days of age and kept in the Nuclear Medicine Center, School of Medicine / USP - São Paulo. The animals were divided into 4 groups of 5 animals for each strain: Control Group (CTL): received intravesical dose of saline for 3 consecutive weeks; MNU Group: received a intravesical dose of N-methyl-N-Nitrosourea (MNU) every 15 days, a total of 3 doses; MNU+BCG Group: received received intravesical dose of BCG for 3 consecutive weeks; MNU+P-MAPA Group: received intravesical dose of P-MAPA for 3 consecutive weeks. After 09 weeks of experiment, urinary bladders were collected and submitted to histopathological and Western blotting analysis. The present study showed that P-MAPA immunotherapy led to distinct activation of the innate immune system TLR2 and 4-mediated when compared to BCG, resulting in increased signaling pathway for interferon (TRIF, IRF3, IFN-α and IFN-γ ) and restoration of the p53 protein ... / Mestre
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The antioxidative and cytotoxic effects of hibiscus sabdariffa on mcf7 and mcf12a breast cell lines

Sobantu, Mandisa Pamela January 2015 (has links)
Thesis (MTech (Biomedical Technology))--Cape Peninsula University of Technology, 2015. / Cancer is the leading cause of death in both developed and developing countries. In particular, breast cancer is regarded as the most common neoplastic disease in females and accounts for the high mortality rates in women. Increased mortality rates could be attributed to ineffective current cancer treatment modalities that have been implicated to cause multidrug resistance, high toxicity and induction of several side effects. In addition, oxidative stress appears to play a role in the development of breast cancer. Therefore, current cancer research aims to search for plant based anticancer compounds with less side effects and toxicity towards the human body. An example of such a plant is Hibiscus sabdariffa also known as roselle and is reported to have bioactive compounds that exhibit anticancer and antioxidant effects. However, the effects of Hibiscus sabdariffa on breast cancer in relation to oxidative stress and apoptosis have not been investigated. In this research study, the aim was to evaluate the cytotoxic and antioxidant effects of water and methanolic extracts of Hibiscus sabdariffa (HS) on cancerous MCF7 and non-cancerous MCF12A breast cell lines with special reference to oxidative stress and apoptosis. This was done based on the fact that HS has been documented for its traditional use against cancer and other ailments.
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Presentation patterns of invasive cancer of the cervix : a Zimbabwean study

Mushosho, Eucaria Yemukayi January 2011 (has links)
Thesis (MTech (Radiography))--Cape Peninsula University of Technology, 2011. / The focus of this study is on the presentation patterns of invasive cancer of the cervix (CaCx) in Zimbabwe. The study was undertaken at a large referral cancer treatment centre in Harare the capital city of Zimbabwe. The main study question addressed was: Are there any changes in the presentation patterns of invasive CaCx in Zimbabwe? This was subdivided into three sub questions: 1) What are the presentation patterns of invasive CaCx among the Zimbabwean women presenting to the major referral centre in terms of histology, stage of the disease, ages of patients, Human immunodeficiency virus (HIV) status and socioeconomic status? 2) What is the trend in the presentation patterns of invasive CaCx in terms of the study variables during the period of study? 3) Are there any correlations that exist among the study variables? This study was conducted because of the sharp contrast that exists in invasive CaCx presentation patterns and incidence between the developed and developing countries. The incidence is now very low in developed countries while it is continuing to rise in developing countries resulting in death among women at a time when they are supposed to be more effective in their families and the nation at large. A retrospective documentary study of patients' files using an observation check list was done from 1998 to 2010. A systematic sample of four years was selected with 1998 as the base year (1998, 2002, 2006 and 2010). To strengthen the sample all the available patients' files for the selected years were considered. On average the majority of the patients (91.75%) presented with squamous cell carcinoma (SCC), 5.5% presented with adenocarcinoma and 2.75% with other types of histology. It was found that (89%) of women presented with late stage disease (stage liB and above). The ages of patients at presentation were between 40 to 60 years. Very few patients had recorded HIV status in 1998 and 2002 but a significant increase in proportion of patients with known HIV status was noted in 2006 (48%) and 2010 (73%). The average percentage for HIV positive patients for 2006 and 2010 was 57% and the average percentage for HIV negative patients was 43%. The majority (58.25%) of the patients were of low socioeconomic status. No significant change in trend was noted for variables except for HIV status where there was a downward trend in the percentage of HIV positive patients and an upward trend in the percentage of HIV negative patients. When correlation analysis was done among the variables no significant association was noted among the variables except that a low degree of association was recorded for the ages of patients and HIV status. The association indicated that young invasive CaCx patients are associated with HIV infection at presentation. The recommendations are that the government should mobilize resources towards prevention and control of invasive cancer of the cervix and awareness campaigns on early presentation should increase. Furthermore the cancer registry should expand its services to cover all health institutions nationwide. It is also recommended that further studies should be done on the presentation patterns of invasive CaCx and of HIV status. Longitudinal studies are recommended in order to monitor changes in presentation patterns.

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