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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.
41

Evaluation of E-cadherin gene expression in cervical carcinomas

Pan, Lin-Lin 28 August 2003 (has links)
Epithelial adhesion molecule, E-cadherin plays important role in maintaining structural integrity of epithelial tissue. Altered expression of E-cadherin might result in the loss of contact inhibition growth property, abnormal cell growth and differentiation, hence the oncogenic transformation. To explore the role of E-cadherin in the tumor progression, we have investigate the expression pattern of E-cadherin in invasive cervical carcinomas. 77 paraffin embedded specimen with FIGO staging Ia¡]N=15¡^, Ib¡]N=19¡^, Ib meta¡]N=13¡^ IIa¡]N=17¡^, IIb¡]N=13¡^were included in immunohistochemical study, 18 surgical removed tumor tissues of Ib stage and its normal counter parts were used for semi-quantitative RT-PCR analysis. The results indicated that no significant correlation between E-cadherin expression level and tumor metasis, patient prognosis. However, E-cadherin immunostainimg intensity was significanty inverse correlated with tumor size¡]p < 0.001¡^. Notably, loss of membranes E-cadherin expression might be a significant factor that correlated with tumor metasis¡]p = 0.001,< 0.005¡^.
42

The expression of TSG101 and RET gene in thyroid carcinoma specimens.

Chao, Fang-Ping 28 August 2001 (has links)
The aim of this thesis is to evaluate the expression of both TSG101 tumor susceptibility gene and ret oncogene in human thyroid carcinoma specimens. Functional inactivation of TSG101 in mouse fibroblast leads to cellular transformation and the ability to form metastatic tumors in nude mice. No genomic deletion of TSG101 gene has been reported in human cancer, casting a doubt on the role of TSG101 as a classical tumor suppressor. Subsequent studies reveal that TSG101 is a frequent target of spilicing defects, which is correlated with cellular stress and p53 status, and might reflect the cellular environment during the cancer development. Furthermore, recent reports demonstrate TSG101 as a part of the MDM2/p53 regulatory circuitry, a well recognized circuitry that upon deregulation results in tumorigenesis. In this study we have analyzed TSG101 gene expression in 85 specimens of thyroid carcinomas. The results indicated that 100% of papillary carcinomas (48/48), 85% of follicular carcinomas (18/21), 91% of medullary carcinomas (10/11) and 60% of undifferentiated carcinomas (3/5) showed strong to moderate cytoplasmic staining, whereas the staining was completely negative, or cytoplasmic dot-staining in the adjacent non-neoplastic follicular cells. Occasionally, the staining could be found in the nucleus. Subsequently, sequence analysis of 17 papillary carcinoma specimens revealed no mutation in steadiness box region, indicating that it might not be the cause of TSG101 protein overexpression. In summary, our results indicate strong correlation of TSG101 overexpression and thyroid carcinomas. Further experiments are urged to clarify the relationship of TSG101 overexpression and thyroid tumorigenesis. Rearrangement of ret proto-oncogene is unique to papillary thyroid carcinoma (PTC). These rearrangements consist of the fusion of ret tyrosine kinase domain to a variety of heterologous genes, thus generating chimeric transforming oncogenes termed, ret/PTC. The frequency of ret/PTC activation in non-radiation exposured adult populations has been reported to vary from 0-55% depending on the geographic distribution. To detect ret rearrangement and to identify candidate of novel ret/PTC in 62 specimens of PTC collected from southern Taiwan, a RT-multiplex PCR method was used to reveal the possible specimens that harbor ret rearrangements. Type specific-PCR amplification and subsequent sequence analysis of PCR product were performed to identify the known types of ret/PTC. We have identified two cases of ret/PTC1, two cases of ret/PTC3 and one case of ELKS-RET. Excitingly, four cases of unknown ret/PTC type were identified. Hence, 5¡¦-RACE strategy will be employed to identify novel ret/PTC in these four specimens.
43

Role of the Sp1-pVHL- HIF-1 £\

Lee, Yi-Chern 01 September 2008 (has links)
Introduction: Since the era of Marshall, H. pylori has been to be implicated in many upper digestive tract diseases, such as gastritis, peptic ulcer disease, mucosa- associated lymphoid tissue lymphoma, and even gastric adenocarcinoma. In 1994, WHO recognized H. pylori as a definite carcinogen for gastric cancer. Many study had shown that microbial pathogens may induce oxidative stress in infected host cell. And this may also represent an important mechanism leading to epithelial injury in H. pyloric infection. Oxidative stress plays a role in altering epithelial cell turnover, accelerating apoptosis and increasing oxidative DNA damage. One of the evidences for this phenomenon is increasing level of reactive oxygen species (ROS) measured in the mucosa of infected stomach. ROS may activate HIF-11£\ transcription. HIF-1£\ overexpression had been detected in several human cancers. Furthermore its overexpression correlates significantly with highly aggressive disease, lymph node metastasis, clinicopathological status and poor prognosis in some cancer types. It may up regulate hypoxia-induced gene, such as the vascular endothelial growth factor (VEGF) transcription and angiogenesis. Therefore we propose Sp1-pVHL-HIF-1£\ pathway may play a role the carcinogenesis in Hp -associated gastric cancer. Material and methods: We took Paraffin-embedded specimens from 89patients, who had undergone UGI endoscopy and gastric mucosa biopsy. We assessed the Sp1, pVHL, HIF-1£\ in all cases by immunohistochemistry and then evaluated their correlation with the H pylori infection. Chi-square and Fisher¡¦s exact test was performed to determine the significance of the difference between Sp1, pVHL, HIF-1£\. Results: There are not significant difference in nuclear Sp1 expression and H. pylori different (p=0.59). Sp1 expression was not significant, (p=0.91, 0.93, 0.36, 0.42, 0.51) with sex, age, location, TNM stage and cell differentiation. pVHL protein was mainly expressed in the cytoplasm. There are no significant difference with H. pylori infection (p=0.14). The relationship pVHL protein expression between with sex, age, lesion site, TNM stage and cell differentiation were not significant (p=0.39, 0.70, 0.69, 0.83, 0.70). HIF-1£\ protein was mainly expressed in the nuclei. There are not significant association with H. pylori infection (p=0.49). There were no significant differences between HIF-1£\ protein expression with sex, age, location, TNM stage and cell differentiation (p=0.94, 0.32, 0.75, 0.35, 0.60). Furthermore, In normal tissue the expression of HIF-1£\ had significant association with pVHL(p=0.0002), and the expression also had no a mariginally significant association with Sp1(p=0.096). Expression of Sp1 had significant association with pVHL(p=0.0016)in tumor tissue, Therewas a significant association between normal and tumor tissue expression of the pVHL and Sp1(p=0.038, 0.019), but the expression of HIF-1£\ had no significant(p=0.23). Conclusion: In this study, we attempt to determine the association between Sp1-pVHL -HIF-1£\ pathway and a role in the carcinogenesis in H. pylori infection. Although we didn¡¦t confirm the hypothesis Sp1-pVHL -HIF-1£\ pathway playing an critical role in the mechanism of gastric cancer. We concluded that there is no significance between the expression of Sp1, pVHL and HIF-1£\ and gastric cancer, but the role of this pathway in the Hp infection associated carcinogenesis is still to be clarified.
44

Immunohistochemical localization of circadian oscillators in the brain and prothoracic glands of the insect rhodnius prolixus

Terry, Katherine L. January 2001 (has links)
Thesis (M. Sc.)--York University, 2001. Graduate Programme in Biology. / Typescript. Includes bibliographical references (leaves 128-145). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pMQ66409.
45

Activation of the transcription factor nuclear factor kappa B in Crohn's disease

Ellis, Richard David January 2000 (has links)
No description available.
46

Tangential distribution of SMI-32 immunoreactive neurons in cat visual cortex

Mareschal, Isabelle January 1994 (has links)
The mammalian visual cortex is believed to be parcellated into functional radial units called modules, which are composed of neurons with similar physiological properties. The first demonstration of modularity was provided in 1957 by Mountcastle in the somatosensory cortex, and has since been demonstrated in the visual cortex, where neurons within a vertical unit of the visual cortex process information about the same portion of the visual field. / A new approach has been proposed for identifying functionally similar neurons by examining their molecular characteristics. Indeed, the arrangement of neurons into functional arrays might be reflected by the presence of specific molecules (e.g Cat-301 patches, cytochrome oxidase blobs). / In this experiment, immunohistochemistry was used to examine the tangential and radial distribution and development of a subset of pyramidal neurons in the kitten and adult cat visual cortex using the monoclonal antibody SMI-32, that recognizes the non-phosphorylated form of neurofilament H. It was found that the neurons recognized by this antibody were grouped into clusters, forming regularly spaced patches in the infragranular and supragranular layers. These anatomical findings support the notion of an intrinsic columnar organization.
47

Vascular shutdown as an effect of using photodynamic therapy to treat cancer

Pascucci, Elizabeth Mary. January 2008 (has links) (PDF)
Thesis (MS)--Montana State University--Bozeman, 2008. / Typescript. Chairperson, Graduate Committee: Jean Starkey. Includes bibliographical references (leaves 70-76).
48

Efeitos biológicos da radioterapia na expressão do fator de crescimento epidérmico (EGF) durante a odontotogênese em camundongos (Mus musculus)

Peixoto, Breno Cherfên [UNESP] 06 July 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-07-06Bitstream added on 2014-06-13T19:45:07Z : No. of bitstreams: 1 peixoto_bc_dr_sjc.pdf: 1055434 bytes, checksum: 3395732c6ce98a786b6ec35e4d15f4d5 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Pacientes portadores de câncer na região de cabeça e pescoço quando submetidos à radioterapia podem apresentar vários tipos de manifestações clínicas, dentre elas a diminuição dos níveis salivares do fator de crescimento epidérmico (EGF). O EGF é uma pequena proteína (53 aminoácidos) que estimula a proliferação de células dos mamíferos, sendo encontrada em vários órgãos em desenvolvimento. Pode também exercer um papel fisiológico na erupção dentária ao interagir com outras moléculas como o fator de crescimento transformante β (TGF-β), a interleucina 1 (IL-1) e do fator de estimulação de colônia 1 (CSF-1), aumentando a reabsorção óssea e estimulando a quimiotaxia de células mononucleares. O objetivo deste trabalho foi verificar, por meio de reações de imuno-histoquímica, se a expressão do fator de crescimento epidérmico (EGF) pode ser alterada na odontogênese do primeiro molar superior de camundongos Mus musculus, após exposição de fêmeas prenhes a radioterapia, na dose de 3 Gray (Gy) ao décimo dia de gestação. Foram avaliados os germes dentários dos embriões aos 14, 16 e 18 dias de desenvolvimento pré-natal. As análises morfológica microscópica óptica e histomorfométrica demonstraram que o número de células epiteliais periféricas do órgão do esmalte imunopositivas para o EGF foi significativamente menor no grupo 3 Gy em relação ao grupo controle nos períodos de 14o (P<0,0001), 16o (P<0,0001<0,05) e 18o (P<0,0008) dias pré-natais. Processo FAPESP no 2008/54534-8. / Malignant neoplasm orofacial patients when receiving radiation therapy can present several types of radiation injuries and clinical manifestations, such as decrease of the salivary epidermal growth factor (EGF) levels. EGF is a small protein (53 amino acids) that stimulates the proliferation of cells of the mammals, being found in several organs in development. EGF can exercise a physiological role in the dental eruption through the interaction with other molecules such as transforming growth factor beta (TGF-β), interleukin-1 (IL-1) and colony-stimulating factor-1 (CSF-1), which increases the bone reabsorption and stimulating the chemotaxis for mononuclear cells. The objective of this work was to verify through technique of immunohistochemistry, changes in the expression of the EGF in the odontogenesis of the first upper molar in Mus musculus mice embryos to the 14th, 16th and 18th days of intrauterine life. Pregnant mice was irradiated on the 10th gestacional day with a 3 Gray (Gy) dose. The microscopical mophological and histomorphometrical analysis showed a significant decrease in the number of EGF-positive dental epithelium cells in the 3 Gy group when compared with control group in 14th (P<0,0001), 16th (P<0,0001<0,05) and 18th (P<0,0008) intrauterine day periods. Supported by FAPESP no 2008/54534-8.
49

Expressão dos fatores de crescimento obtidos do plasma rico em plaquetas, no tratamento de fraturas experimentais do radio de cães /

Souza, Talita Floering Brêda. January 2010 (has links)
Orientador: Alexandre Lima de Andrade / Banca: Paola Castro Moraes / Banca: Maria Gisela Laranjeira / Resumo: O objetivo deste trabalho foi o de avaliar a cicatrização óssea de fraturas experimentais do radio de cães, tratadas ou não com o PRP autógeno, por meio de estudos radiográfico, densitométrico e histológico; bem como avaliar a expressão dos fatores de crescimento do PRP. Foram utilizados 21 cães inicialmente agrupados de acordo com o tempo de colheita de biopsia: aos sete dias (n=10) ou 60 dias (n=11) que foram alocados aleatoriamente em dois grupos experimentais: o grupo controle (G-controle, n=11) e o grupo PRP (G-PRP, n=10). Todos os animais foram submetidos à osteotomia e osteossíntese (fixador esquelético externo) do rádio direito, gerando-se um "gap" de 2,0mm, que foi preenchido ou não com PRP. Os estudos radiográficos e densitométricos foram realizados no pós-operatório imediato e até 60 dias de pós-operatório. As avaliações histológicas e imunoistoquímicas foram realizadas aos sete e 60 dias. Os dados encontrados foram tratados estatisticamente (p<0,05). Houve diferença significativa nas avaliações radiográficas e densitométricas entre os grupos. A avaliação histológica evidenciou uma cicatrização óssea mais avançada aos 60 dias no G-PRP e união óssea tardia no G-controle. Houve imunomarcação intensa do PDGF-B e TGF-β no G-PRP aos sete e 60 dias de pós-operatório. Conclui-se, que o PRP pode ser utilizado como terapia adjuvante, pois promoveu melhor cicatrização óssea em fraturas experimentais ("gap" de 2,0mm) do radio de cães tratadas com fixador esquelético externo. Ainda houve maior expressão do PDGF-B e TGF-β nos períodos, precoce e tardio, dos animais tratados com PRP / Abstract: The present article aimed to assess bone healing of experimental radial fractures, treated or not with autologous PRP, by means of radiographic, densitometric and histological studies and evaluate the expression of growth factors in PRP. Were used 21 dogs initially grouped according to the time of biopsy collection: seven days (n = 10) or 60 days (n = 11) were randomly assigned to two groups: the control group (G-control, n = 11) and the PRP group (G-PRP, n = 10). All animals underwent osteotomy and fixation (external skeletal fixation) of the right radius, generating a gap of 2.0 mm, which was filled or not with PRP. Radiographic and densitometry studies were performed in the immediate postoperative period and to 60 days after the surgery. The histological and immunohistochemical evaluations were performed at seven and 60 days. The data were treated statistically (p <0.05). There were significant differences in densitometric and radiographic evaluations between the groups. Histological evaluation showed a more advanced bone healing at 60 days in G-PRP and bone union late in the G-control. There was intense expression of PDGF-B and TGF-β in G-PRP from seven to 60 days postoperatively. It is concluded that the PRP can be used as adjuvant therapy, because it provided better bone healing in experimental fractures (gap of 2.0 mm) radius of dogs treated with external skeletal fixation. Although there was a higher expression of PDGF-B and TGF-β in periods, early and late, the animals treated with PRP / Mestre
50

Press imprint smear: um mÃtodo simples, rÃpido e de baixo custo no diagnÃstico de Leishmaniose cutÃnea. / Press imprint smear: A simple, quick and cheap method in the diagnosis of cutaneous leishmaniasis

ClaudÃnia Costa Praciano 29 July 2014 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / A leishmaniose cutÃnea (LC) à a forma mais comum da leishmaniose, com 1 milhÃo de novos casos por ano. Apresenta um amplo espectro clÃnico, podendo ser confundida com outras doenÃas que acometem a pele. Desse modo, à de fundamental importÃncia o diagnÃstico rÃpido e preciso da doenÃa. O diagnÃstico parasitolÃgico à o mais utilizado na rotina laboratorial, entretanto o exame direto geralmente apresenta baixa sensibilidade. Em virtude disso, torna-se necessÃrio buscar tÃcnicas alternativas para o diagnÃstico das leishmanioses. Neste trabalho, comparou-se o teste do press imprint smear com o exame histolÃgico e a imuno-histoquÃmica, no diagnÃstico direto de leishmaniose cutÃnea. Pacientes com suspeita clinica de LC foram submetidos à coleta de duas biÃpsias da borda das lesÃes, com punch de 3 mm, para a realizaÃÃo dos testes: press imprint smear, exame histolÃgico e imuno-histoquÃmica. Este Ãltimo foi considerado o teste padrÃo ouro. O press imprint smear consistiu em esmagar o fragmento de biÃpsia entre duas lÃminas de vidro sob pressÃo, de tal modo que o extrato (suco) tissular se espalha na superfÃcie das duas lÃminas. Os esfregaÃos foram corados com Giemsa, para pesquisa de amastigotas. Outro fragmento foi fixado em formalina a 10%. Desta amostra, uma lÃmina foi utilizada no exame histolÃgico, corada com hematoxilina-eosina, e outra para o teste de imuno-histoquÃmica. Ao total, foram incluÃdos 78 pacientes com diagnÃstico clinico-epidemiolÃgico de LC. A tÃcnica do press imprint smear e o exame histolÃgico foram realizados na amostra de todos os pacientes. Entretanto, a imuno-histoquÃmica foi realizada em apenas 73 amostras. Setenta e dois (98,6%) foram positivos para Leishmania na imuno-histoquÃmica, com sensibilidade de 98,6%; o press imprint smear foi positivo em 48 pacientes (61,5%), com sensibilidade de 58,3%. No exame histolÃgico foram identificadas amastigotas em 35 pacientes (44,9%), apresentando sensibilidade de 45,8%. Os resultados mostraram que o press imprint smear apresentou maior sensibilidade do que o exame histolÃgico, para o diagnÃstico da leishmaniose cutÃnea. AlÃm disso, à uma tÃcnica de baixo custo e fÃcil execuÃÃo. / The cutaneous leishmaniasis (CL) is the most common form of leishmaniasis, with 1 million new cases per year. Presents a broad clinical spectrum, which may be confused with other diseases that affect the skin. Thus, it is of fundamental importance to rapid and accurate diagnosis of the disease. Parasitological diagnosis is the most used test in laboratory routine, however direct examination generally has low sensitivity. As a result, it becomes necessary to find alternative techniques for the diagnosis of leishmaniasis. This study compared the test press imprint smear with histological examination and immunohistochemistry, for the direct diagnosis of leishmaniasis. Patients with clinical suspicion of LC underwent a sampling from two samples of biopsies from the edge of the lesions, with a punch of 3 mm for the tests: press imprint smear, histological examination and immunohistochemistry. The latter was considered the gold standard test. The press imprint smear consisted in crushing the biopsy fragment between two glass plates under pressure so that the extract (juice) tissue spreads on the surface of the two blades. The smears were stained with Giemsa for the detection of amastigotes. Another fragment was fixed in 10% formalin. From this sample, a blade was used in histology, stained with hematoxylin-eosin, and one for the immunohistochemical test. In total, 78 patients were included with clinical and epidemiological diagnosis of LC. The press imprint smear technique and histologic examination were conducted on the sample of all patients. However, immunohistochemistry was performed in only 73 samples. Seventy-two (98,6%) were positive for leishmania in immunohistochemistry, with sensitivity of 98,6%; the press imprint smear was positive in 48 patients (61,5%), with sensitivity of 58,3%. In the histological examination were identified amastigotes in 35 patients (44,9%), with sensitivity of 45,8%. The press imprint smear was more sensitive than histological examination for the diagnosis of cutaneous leishmaniasis. In addition, a technique is inexpensive and easy to perform.

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