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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.
331

Importância da resposta aos epítopos subdominantes, da proliferação e da recirculação de linfócitos T CD8+ durante a vacinação experimental contra a infecção pelo Trypanosoma cruzi. / Importance of the response to subdominant epitope, proliferation and recirculation of CD8+ T lymphocytes during experimental vaccination against Trypanosoma cruzi infection.

Dominguez, Mariana Ribeiro 14 November 2013 (has links)
Neste trabalho nós estudamos qual seria o impacto da indução de resposta imune a epítopos CD8 subdominantes na imunidade gerada pela vacinação genética. Durante a infecção experimental apenas um epítopo imunodominante presente no antígeno ASP-2 é reconhecido. Já os linfócitos T CD8+ induzidos nos animais vacinados com o gene da ASP-2 são capazes de reconhecer além deste mais dois outros epítopos (subdominantes). A identificação desses epítopos permitiu que estudássemos o papel da resposta imune a epítopos subdominantes na imunidade protetora. Após imunização genética com o gene da ASP-2 mutado, sem resposta para o epítopo dominante, confirmamos que a resposta imune aos epítopos subdomiantes pode contribuir na proteção contra a infecção experimental. Apesar do papel critico dos linfócitos T CD8+ na resposta imune protetora induzida pela vacinação genética do tipo imunização e reforço heterólogo, não se sabe ao certo se após o desafio experimental estes linfócitos T CD8+ necessitam proliferar ou recircular para mediar a imunidade protetora. Nossos resultados desafiam o paradigma de ação das vacinas tradicionais de que a imunidade é dependente da proliferação e não da recircular dos linfócitos T de memória e para mediar a imunidade protetora. / In the present study, we evaluated the impact of the immune response to sub-dominant CD8 epitopes on immunity generated by genetic vaccination. During experimental infection only a single dominant epitope is recognized on the antigen ASP-2. In contrast, the CD8+ T lymphocytes induced in animals genetically vaccinated with ASP-2 recognized, in addition to the dominant epitope, two other epitopes (sub-dominants). The identification of these epitopes allowed us to test the role of immune response to sub-dominant epitopes in protective immunity. After genetic vaccination with ASP-2 mutated gene, without the response to dominant epitope, we concluded that the immune response to the sub-dominant epitopes can be important to protective immunity. In spite of the critical role of CD8+ T lymphocytes in protective immune response induced by genetic vaccination using the heterologous prime-boost regimen, it is unclear whether after the experimental challenge these CD8+ T lymphocytes need to proliferate or recirculate to mediate protective immunity. Our results challenge the paradigm of action of traditional vaccines that immunity is dependent on the proliferation of memory T lymphocytes and that these cells do not need to recirculate.
332

The positive role of thromboxane A2 (TxA2) and Its receptor in lung cancer cell growth induced by smoking carcinogen 4-methylnitrosamino-1-3-pyridyl-1-butanone (NNK). / CUHK electronic theses & dissertations collection

January 2012 (has links)
肺癌是一個世界性的健康難題。大量研究證據顯示,煙草及其致癌物NNK對環氧酶(COX)-2及其下游產物具有促進效應。血栓素(TxA)2是COX-2的關鍵性下游產物之一,該論文闡述了TxA2在NNK導致的肺癌增長中的可能作用。 / 我們發現相对于非吸烟者,吸煙者肺癌組織表达更高水平的TxA2合酶(TxAS)。NNK可以刺激培養的肺癌細胞TxA2合成。用TxAS抑制劑和TxA2受體(TP)拮抗劑分別阻抑TxA2的合成與功能可以引起細胞凋亡,從而有效抑制NNK導致的細胞增殖效應。在TxA2合成受抑制的情況下,TP激動劑U46619幾乎可以重建NNK效應,說明TP在NNK效應中的重要作用。研究還顯示,激活的TP可以通過PI3K/Akt和ERK通路進一步激活CREB,從而參與NNK對肺癌細胞的促生長效應。 / 緊接著,我們的研究顯示TP 可以調節NNK對COX-2 和TxA2的誘導,而且發現NNK刺激的TxA2合成主要依賴於COX-2活性。COX-2和TxA2功能抑製劑對NNK的促細胞生長作用具有相似的抑制效用。考慮到TP是TxA2的功能受體,該資料說明TP在NNK處理的肺癌細胞中傳遞了上游因子COX-2的促腫瘤作用。在使用COX-2小干擾RNA(siRNA)抑制NNK作用的情況下,TP激動劑U46619幾乎可以恢復NNK的效應證實了TP的傳遞者角色。研究還發現 TPα而不是TPβ在培養的肺癌細胞系中廣泛表達,並且過表達TPα具有促進腫瘤生長的作用。在用NNK處理細胞的條件下,TPα還具有促COX-2表達和TxA2生成的作用。 / 我們的研究進一步發現,在吸煙者肺癌組織中TPα表達增高,這與TxAS的表達相似。与此结果相一致,在經NNK處理的A/J小鼠肺癌組織中,TxAS和TP表達水準也是明顯上升的。在細胞培養實驗中,NNK能夠提高TxAS蛋白和信使RNA(mRNA)的表達水準。但是,在TP的兩個亞型TPα和TPβ中, NNK僅能促進TPα的蛋白表達,對它們的mRNA均無影響。NNK對TxAS的促表達作用是核轉錄因數(NF)-κB依賴性的。其他的幾個關鍵轉錄因數,諸如特異性蛋白(SP)-1,CREB和活化受體 (PPAR)γ均未參與NNK對TxAS和TPα的表達促進作用。進一步的,轉錄後機理被證實參與了NNK對TPα的作用。TPα而不是TPβ經鑒別在NNK的促NF-κB 激活 和 促TxAS 表達效應中起正向調節作用。 / 總之, 我們的研究說明TxA2相關通路在NNK的促肺癌細胞生長效應中起正向調節作用。我們的研究揭示了TPα的自我激活環路。通過該環路,TxA2,或者說TxAS和TPα參與了NNK的肺癌促生長效應。因此,我們的研究為肺癌的防治了提供了一個新的方向,即靶向TxAS和TPα是一種可能有效的策略。 / Lung cancer concerns a world-wide health problem. There is considerable evidence of that tobacco smoke and its carcinogen 4-methylnitrosamino-1-3-pyridyl-1-butanone (NNK) have the potential effects on the production of cyclooxygenase (COX)-2 and its downstream products in tumor cells. This thesis is constructed to describe the study focused on the role of thromboxane A2 (TxA2), one of the key downstream products of COX-2, in NNK-induced lung tumor growth. / We found that as compared to non-smokers, lung cancer tissues obtained from smokers tended to express more TxA2 synthase (TxAS). Moreover, NNK could stimulate TxA2 synthesis in lung cancer cells. Blockade of TxA2 synthesis and action by TxAS inhibitor and TxA2 receptor (TP) antagonist completely blocked NNK-promoted cell proliferation via inducing apoptosis. Moreover, TP agonist U46619 reconstituted a near full proliferative response to NNK when TxAS was inhibited, affirming the role of TP in NNK-induced cell growth. Furthermore, we revealed that the activated TP may then activate CREB through PI3K/Akt and ERK pathways, thereby contributing to the NNK-induced lung cancer cell growth. / We subsequently showed that TP could modulate the induction of COX-2 and TxA2 by NNK. The synthesis of TxA2 stimulated by NNK was found to be mainly dependent on COX-2 activity. Intriguingly, there are similar inhibitory effects on NNK-induced cell growth between pharmacological inhibition of COX-2 and the blockade of TxA2 synthesis and action. Because TP is the natural receptor of TxA2, these results suggest that TP may function as a mediator for the tumor-promoting effects of COX-2 upon NNK treatment, which was confirmed by the data showing that U46619 almost restored NNK effects in the presence of COX-2-siRNA. Importantly, TPα, but not TPβ was found to be widely expressed in lung cancer cells and be able to promote tumor growth, COX-2 expression and TxA2 synthesis upon NNK treatment. / We further demonstrated that in lung tumor tissues obtained from smoker, TPα protein was increased, which was similar to the change in TxAS protein. The increased levels of TxAS and TP proteins were also found in lung cancer tissues of A/J mice treated with NNK. In cell culture experiments, NNK could increase TxAS at both protein and mRNA levels. However, TPα rather than TPβ was increased by NNK at protein but not mRNA level. NNK-stimulated TxAS expression was dependent on nuclear factor (NF)-κB signaling. Other key transcriptional factors, such as specificity protein(SP)-1, CREB and peroxisome proliferator-activated receptor-gamma (PPARγ), were not involved in NNK-induced TxAS and TPα expression. Further experiments revealed that post-transcriptional mechanisms were responsible for NNK-induced TPα expression. TPα rather than TPβ was finally identified to have a positive role in NNK-induced NF-κB activation and TxAS expression. / Taken together, our study suggests that TxA2 pathway has a positive role in NNK-induced lung cancer cell growth. An auto-positive feedback loop of TPα activation to facilitate lung tumor growth in the presence of NNK is delineated by these results. Therefore, targeting TxAS or/and TPα may represent a promising strategy for prevention and treatment of lung cancer. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Huang, Runyue. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 119-146). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / Abstract --- p.I / 摘要 / Publications / Acknowledgement / Abbreviations / Table of contents / Chapter Chapter 1 --- General introduction--Tobacco smoking, COX-2 pathway and cancer / Chapter 1.1 --- Abstract --- p.1 / Chapter 1.2 --- Introduction --- p.2 / Chapter 1.3 --- Cyclooxygenase and prostanoids --- p.5 / Chapter 1.4 --- The effects of tobacco smoking on COX-2 pathway, and the related pathologies --- p.8 / Chapter 1.4.1 --- Smoking, PGE2, inflammation and immunosupression --- p.8 / Chapter 1.4.2 --- Smoking, TxA2, platelet activation, cell contraction and angiogenesis --- p.11 / Chapter 1.4.3 --- Smoking and PGI2 --- p.16 / Chapter 1.5 --- The role of cyclooxygenase-2 pathway in the progression of tobacco smoke-related cancers --- p.19 / Chapter 1.5.1 --- Lung cancer --- p.19 / Chapter 1.5.2 --- Gastrointestinal cancer --- p.23 / Chapter 1.5.3 --- Bladder cancer --- p.24 / Chapter 1.5.4 --- Head and neck squamous cell carcinoma --- p.25 / Chapter 1.5.5 --- The signaling mechanisms underlying the induction of COX-2 by smoking in tumors --- p.26 / Chapter 1.6 --- Summary, future directions and key questions --- p.28 / Chapter Chapter 2 --- NNK induces lung cancer cell growth by stimulating TxA2 and its receptor / Chapter 2.1 --- Abstract --- p.32 / Chapter 2.2 --- Introduction --- p.33 / Chapter 2.3 --- Materials and Methods --- p.35 / Chapter 2.3.1 --- Cell lines and cell culture --- p.35 / Chapter 2.3.2 --- Chemicals and drug treatment --- p.35 / Chapter 2.3.3 --- Thromboxane B2 EIA assay --- p.36 / Chapter 2.3.4 --- MTT assay --- p.36 / Chapter 2.3.5 --- BrdU cell proliferation assay --- p.37 / Chapter 2.3.6 --- Flow cytometry for analysis of apoptosis --- p.37 / Chapter 2.3.7 --- Transfection of cells with CREB siRNA --- p.38 / Chapter 2.3.8 --- Western blot analysis and antibodies --- p.38 / Chapter 2.3.9 --- Statistical analysis --- p.39 / Chapter 2.4 --- Results --- p.41 / Chapter 2.4.1 --- High expression of TxAS in lung cancer tissues of smoker --- p.41 / Chapter 2.4.2 --- NNK stimulated TxA2 synthesis in lung cancer cells --- p.43 / Chapter 2.4.3 --- Blockade of TxA2 synthesis and action prevented NNK-induced cell growth --- p.44 / Chapter 2.4.4 --- TxA2 mimetic U46619 reconstituted NNK-enhanced cell proliferation under TxA2-inhibited condition --- p.47 / Chapter 2.4.5 --- Blockade of TxA2 synthesis or action induced the apoptosis of the NNK-exposed cells --- p.47 / Chapter 2.4.6 --- CREB is accountable for the key role of TxA2 in NNK-enhanced cell proliferation --- p.49 / Chapter 2.4.7 --- PI3K/Akt and ERK rather than JNK and p38 pathways were mediated by TxA2 in the NNK-exposed cells --- p.52 / Chapter 2.4.8 --- CREB is located downstream of the PI3K/Akt and ERK pathways in NNK-treated cells --- p.53 / Chapter 2.5 --- Discussion --- p.55 / Chapter Chapter 3 --- The positive role of TPα in the induction of COX-2, TxA2 and cell growth by NNK in human lung cancer cells / Chapter 3.1 --- Abstract --- p.62 / Chapter 3.2 --- Introduction --- p.63 / Chapter 3.3 --- Materials and methods --- p.65 / Chapter 3.3.1 --- Cell culture and chemicals --- p.65 / Chapter 3.3.2 --- Transient transfections --- p.66 / Chapter 3.3.3 --- TxB2 measurement --- p.66 / Chapter 3.3.4 --- Cell growth detection --- p.67 / Chapter 3.3.5 --- Analysis of apoptosis --- p.67 / Chapter 3.3.6 --- Western blot analysis and antibodies --- p.67 / Chapter 3.3.7 --- Statistical analysis --- p.68 / Chapter 3.4 --- Results --- p.70 / Chapter 3.4.1 --- Examination of TP as the modulator for induction of COX-2 and TxA2 by NNK --- p.70 / Chapter 3.4.2 --- The TxA2 generated in cells treated with NNK is mainly dependent on COX-2 activity --- p.72 / Chapter 3.4.3 --- Examination of TP as the key mediator for the tumor-promoting effect of COX-2 --- p.72 / Chapter 3.4.4 --- The expression and action of α and β isoforms of TP in human lung cancer cells --- p.77 / Chapter 3.4.5 --- the identification of positive role of TPα in NNK-induced COX-2, TxA2 and cell growth in lung cancer cells --- p.79 / Chapter 3.5 --- Discussion --- p.81 / Chapter Chapter 4 --- TP-α facilitates lung tumor growth through an autoregulatory feedback mechanism / Chapter 4.1 --- Abstract --- p.88 / Chapter 4.2 --- Introduction --- p.89 / Chapter 4.3 --- Materials and methods --- p.91 / Chapter 4.3.1 --- Human lung tissue and immunohistochemical analysis --- p.91 / Chapter 4.3.2 --- Animal treatment --- p.91 / Chapter 4.3.3 --- Cell culture and chemicals --- p.92 / Chapter 4.3.4 --- Transient transfection --- p.93 / Chapter 4.3.5 --- Real-time PCR --- p.93 / Chapter 4.3.6 --- Western blot analysis and antibodies --- p.94 / Chapter 4.3.7 --- Statistical analysis --- p.95 / Chapter 4.4 --- Results --- p.96 / Chapter 4.4.1 --- The effects of smoking on the expression of TP in human lung cancer tissue --- p.96 / Chapter 4.4.2 --- The effects of NNK on the expression of TxAS and TP in lung tissues of A/J mice --- p.98 / Chapter 4.4.3 --- The effects of NNK on the expression of TxAS and TPα in lung cancer cells --- p.99 / Chapter 4.4.4 --- Identification of the roles of NF-κB, CREB and SP1 in NNK-induced TxAS and TPα expression --- p.101 / Chapter 4.4.5 --- The negative role of PPARγ in NNK-induced TxAS and TPα expression --- p.104 / Chapter 4.4.6 --- NNK-induced TPα expression via post-transcriptional mechanism --- p.105 / Chapter 4.4.7 --- Examination of TPα auto-activation mechanism in lung cancer cells stimulated with NNK --- p.106 / Chapter 4.5 --- Discussion --- p.109 / Chapter Chapter 5 --- Conclusion and future works / Chapter 5.1 --- Conclusion --- p.114 / Chapter 5.2 --- Future works --- p.115 / Chapter 5.2.1 --- The possible role of miR-34c in the auto-regulatory loop of TxAS expression or TPα activation --- p.116 / Chapter 5.2.2 --- The possible role of FOXO3a in the auto-regulatory loop of TxAS expression or TPα activation --- p.116 / References --- p.119
333

Lesões primárias e recidivantes do tumor odontogênico queratocístico e cisto odontogênico ortoqueratinizado : casuística e análise histoquímica, imuno-histoquímica da proliferação celular e citoqueratinas /

Silva, Marceli Moço. January 2010 (has links)
Resumo: O queratocisto odontogênico paraqueratinizado foi recentemente reclassificado pela Organização Mundial de Saúde como tumor odontogênico queracístico (TOQ), sendo atualmente considerado uma neoplasia benigna com alta atividade proliferativa e marcada tendência à recidiva. O cisto odontogênico ortoqueratinizado (COO) ainda é classificado como cisto odontogênico, pois apresenta um crescimento mais lento e ausência de recidivas. A opção por um tratamento mais radical ou mais conservador para estas lesões depende destas variações microscópicas. Uma vez que microscopicamente ambas as lesões possuem algumas características em comum, é de interesse clínico e científico o estudo aprofundado delas, incluindo as suas casuísticas. O presente trabalho teve por objetivo realizar um estudo da casuística, histoquímico com AgNOR e imuno-histoquímica com marcadores de proliferação celular (PCNA, Ki-67 e P53) e citoqueratinas (K7, K10-13, K15, K18 e K19) dos casos de TOQ, recidivas desta lesão e COO diagnosticados no Laboratório de Patologia da Faculdade de Odontologia do Campus de Araçatuba, UNESP. Com base nos resultados observados e nas condições em que o trabalho foi desenvolvido, concluiu-se que a maior parte dos TOQs e todos COOs ocorreram preferencialmente em pacientes jovens da raça branca, com lesões assintomáticas, radiolúcidas uniloculares, localizadas principalmente na região posterior de mandíbula. Quanto ao comportamento clínico e características imuno-histoquímicas, o TOQ apresentou maior proliferação celular em relação ao COO, condizente com sua suposta natureza neoplásica, com destaque aos casos com história de recidiva, que apresentaram quantidade maior de células Ki-67 positivas / Abstract: The odontogenic keratocyst was recently reclassified by the World Health Organization as a keratocystic odontogenic tumor (KCOT), being currently considered a benign neoplasia with high proliferative activity and a marked tendency to recur. The orthokeratinized odontogenic cyst (OOC) is still classified as an odontogenic cyst, since it shows slower growth and no recurrence. Opting for a more radical or more conservative treatment for those lesions depends on those microscopic variations. Once microscopically those lesions have some common features, it is of clinical and scientific interest to study them in depth, including their casuistics. This study aimed to analyze the casuistics of KCOTs, of the recurrences of those lesions, and od OOC diagnosed at the Pathology Laboratory of Araçatuba Dental School, UNESP, as well as to conduct histochemical characterization of those lesions with AgNOR and immunohistochemical analysis with cell proliferation markers (PCNA, Ki-67 and P53) and cytokeratins (K7, K10-13, K14, K18 and K19). Based on the results observed and on the conditions under which the study was carried out, it was concluded that most KCOTs and OOCs occurred preferentially in young white patients, with asymptomatic radiolucent unilocular lesions, located mainly in the posterior mandible. As for the clinical and immunohistochemical features, KCOTs showed greater cell proliferation as compared to OOCs, consistent with their supposed neoplastic nature, especially in the cases with history of recurrence, which showed larger amount of positive Ki-67 cells / Orientador: Marcelo Macedo Crivelini / Coorientador: Gilberto Aparecido Coclete / Banca: Alessandra Marcondes Aranega / Banca: Glauco Issamu Miyahara / Banca: Luiz Eduardo Blumer Rosa / Banca: Décio Dos Santos Pinto Júnior / Doutor
334

Correlação da ciclooxigenase-2 com Ki-67, P53 e Caspase-3 nas neoplasias de mama de cadela /

Nardi, Andrigo Barboza de. January 2007 (has links)
Orientador: Carlos Roberto Daleck / Co-oorientador: Renée Laufer Amorin / Banca: Ney Luiz Pippi / Banca: Mirela Tinucci Costa / Banca: Gilson Hélio Toniollo / Banca: Duvaldo Eurides / Resumo: Tendo em vista a relação da ciclooxigenase-2 (COX-2) com a progressão do câncer, este trabalho teve como objetivo investigar a expressão da atividade desta enzima com a imunorreativadade do Ki-67 , P53 e Caspase-3 no diagnóstico e prognóstico de neoplasias mamárias em cadelas. Para a realização deste estudo foram selecionadas 60 amostras de tumores mamários de cadelas. As amostras foram divididas em seis grupos, com 10 tumores em cada grupo, de acordo com a classificação histopatológica. Nos grupos adenoma, carcinoma com prognóstico bom e carcinoma com prognóstico ruim a seleção dos casos se deu pela classificação histológica e evolução clínica do tumor. Os outros 30 tumores foram representados por 10 amostras de carcinoma primário metastático, 10 de metástase pulmonar e 10 de carcinoma inflamatório. A avaliação da expressão da COX-2 (Dako, CX-294), Ki67 (Dako, M7240), P53 (Novocastra, CM1), Caspase-3 (Neomarkers, Asp175) foi conduzida por imunoistoquímica, utilizando-se a técnica de estreptoavidina-biotinaperoxidase. Em relação aos resultados houve correlação da expressão da COX-2 com o índice de proliferação celular Ki-67 no grupo dos adenomas, metástases pulmonares e carcinomas inflamatórios (P<O,05). Em todos os grupos estudados a COX-2 apresentou correlação com a proteína P53 (P<0,01). Observou-se correlação da expressão da ciclooxigenase-2 com a Caspase-3 no grupo dos carcinomas primários metastáticos e nas metástases pulmonares (P<0,05). A expressão da ciclooxigenase-2 variou de acordo com a agressividade das neoplasias mamárias nos casos de adenoma, carcinoma metastático e carcinoma não metastáticos (P<O,05). A sobrevida das pacientes com neoplasias mamária no pós-operatório está ligada à expressão da COX-2, no grupo dos adenomas, carcinoma com prognóstico bom e carcinoma com prognóstico ruim (P<O,01). / Abstract: Considering the relationship between cyclooxygenase-2 (COX-2) with the cancer evolution, this study aimed to detect the expression of this enzyme with the immunoreactive of Ki-67, P53 and Caspase-3 in the diagnosis and prognostic of mammary neoplasms in bitches. Sixty mammary tumors samples were selected for the accomplishment of this study. The samples were divided into six groups, contenting 10 tumors in each group, in accordance to histopathology classification. In adenoma, good prognosis carcinoma and poor prognosis carcinoma groups the criteria for selection was made by histology classification and clinical tumor evolution. The others 30 tumors samples were represented by 10 samples of metastatic primary carcinoma, 10 of pulmonary metastases, and 10 of inflammatory carcinoma. The evaluation of the COX-2 (Dako, CX-294), Ki-67 (Dako, M7240), P53 (Novocastra, CM1), Caspase-3 (Neomarkers, Asp175) expression was achieved by immunohistochemistry, by means of streptavidine-biotine-peroxidase. About the results a positive correlation between COX-2 and the cellular proliferation index Ki-67 was found in the adenomas, pulmonary metastases, and inflammatory carcinomas groups (P<0,05). In ali studied groups the COX-2 presented correlation with P53 protein (P<O,01). There was correlation of cyclooxygenase-2 with caspase-3 in the primary metastatic carcinoma and in the pulmonary metastases group (P<0,05). The cyclooxygenase-2 expression varied in accordance with aggressiveness of mammary neoplasms in cases such adenoma, metastatic carcinoma, and non metastatic carcinoma (P<0,05). The post operative survival rate of patients with mammary neoplasms was linked to COX-2 expression in the adenomas, good prognosis carcinoma and poor prognosis carcinoma groups (P<O,01). / Doutor
335

Imunomodulação por tumores associados ao papilomavírus humano. / Immunomodulation by human papillomavirus associated tumors.

Simone Cardozo Stone 13 March 2013 (has links)
O câncer cervical é o segundo mais comum em mulheres em países em desenvolvimento, sendo causado por infecção persistente por Papilomavírus Humano (HPV). Quando esta persistência ocorre, entre outros fatores, está relacionada a mecanismos de evasão do sistema imune apresentados pelo vírus. A frequência de macrófagos aumenta com a progressão da lesão cervical e há aumento de células mielóides no baço de camundongos com tumor. Este trabalho tem como objetivo observar os efeitos sistêmicos de tumores associados ao HPV sobre a proliferação e recrutamento de células do sistema imune e identificar fatores que tenham papel nesses mecanismos. Utilizando modelos de tumor in vivo, observou-se que tumores associados ao HPV recrutam mais células para o tumor e induzem maior proliferação celular. Também avaliamos o perfil de expressão de citocinas nas linhagens tumorais e o perfil geral de expressão de proteínas através de eletroforese 2D. Com isto, demonstramos que linhagens tumorais positivas para HPV apresentam maior expressão de IL-6, IL-8, CXCL1, sICAM e Serpina E1. / Cervical cancer is the second most common type of cancer in women in developing countries. Its main etiologic factor is persistent infection with high risk human papillomavirus (HPV). This persistence occurs only in some cases and, among other factors, is related to mechanisms of immune evasion displayed by the virus. There is an increase in the frequency of macrophages proportional to cervical intraepithelial lesion grade and an increase of myeloid cells in the spleen of tumor bearing mice. This work aims to observe the systemic effects of HPV associated tumors on the proliferation and recruitment of immune cells, and identify factors that have a role in these mechanisms. Using in vivo tumor models, we found that HPV positive tumors recruit a higher percentage of cells and induce cellular proliferation. We also studied cytokine expression profiles of tumor cell lines, and performed proteomic assay with tumor cells transduced with HPV oncogenes. Our data shows that HPV associated tumor cell lines display higher expression of IL-6, IL-8, CXCL1, sICAM and Serpin E1.
336

Uso de nanopartícula lipídica como veículo do quimioterápico docetaxel no tratamento da aterosclerose induzida em coelhos / Use of lipid core nanoparticle as a vehicle of the chemotherapeutic docetaxel in the treatment of atherosclerosis induced in rabbits

Bianca Meneghini Gomes 26 July 2018 (has links)
Considerada como uma nova estratégia no direcionamento de fármacos para tecidos lesionados, a LDE é uma nanopartícula lipídica que se concentra em locais inflamatórios com altas taxas de proliferação celular, como lesões ateroscleróticas, e é usada em modelos experimentais e no homem. Docetaxel (DTX), agente quimioterápico antiproliferativo, ainda não foi explorado no tratamento da aterosclerose. Coelhos New Zealand brancos machos foram alimentados com ração enriquecida com 1% de colesterol para induzir aterosclerose ao longo do período experimental de 8 semanas. Após 4 semanas, os animais foram tratados semanalmente com LDE-DTX (n =9) com dose de 1 mg/kg e.v. ou apenas com LDE (grupo Controle, n =9). O consumo de ração e os perfis lipídico, hematológico e ponderal foram avaliados durante o protocolo nos tempos basal, 4 semanas e final. Após a eutanásia, foram realizadas análises morfológicas e Western blot das aortas. Como esperado, o colesterol total aumentou aproximadamente 42 vezes em ambos os grupos quando comparados os períodos basal e final. Houve diminuição no número de hemácias entre os períodos basal e final em ambos os grupos, aparentemente não relacionada ao tratamento. Os animais não apresentaram toxicidade renal e hepática. A área de lesão macroscópica nas aortas do grupo LDE-DTX foi aproximadamente 80% menor em relação ao Controle e a área de placa na região do arco aórtico foi 86% menor no grupo tratado com LDE-DTX quando comparado ao Controle. Em relação aos fatores inflamatórios, a expressão proteica de CD68 foi 64% menor no grupo tratado com LDE-DTX quando comparado ao grupo Controle. MCP-1 foi 84% menor no grupo tratado com LDEDTX e o TNF-alfa foi 44% menor no grupo tratado, quando comparados ao grupo Controle. A expressão proteica de interleucina IL-1beta e do NFkB foram cerca de 60% menores no grupo tratado assim como a IL-6, que foi 79% menor, ambos comparados ao grupo Controle. O fator de von Willebrand foi cerca de 30% menor no grupo tratado com LDE-DTX comparado ao Controle. Os fatores próapoptóticos apresentaram menor expressão no grupo LDE-DTX: a caspase 3 foi 82% menor em comparação ao Controle, caspase 9 e Bax, cerca de 50% menor que o controle bem como o fator anti-apoptótico Bcl-2. A expressão proteica dos colágeno I e III também foi menor no grupo LDE-DTX. Comparados ao controle, a expressão proteica de MMP-2 e MMP-9 foram cerca de 70% menores no grupo LDE-DTX. O marcador de proliferação celular PCNA foi 41% menor no grupo LDE-DTX em comparação com o grupo Controle. O tratamento com a associação LDE-DTX mostrou-se eficaz, uma vez que os coelhos tratados apresentaram uma área menor da lesão aterosclerótica, menor inflamação, morte celular e proliferação na aorta quando comparado ao grupo Controle / Considered as a new strategy of targeting drugs to injured tissues, LDE, a lipid core nanoparticle concentrates on inflammatory sites with high cell proliferation rates, as atherosclerotic lesions, and it is used as a vehicle for drugs in experimental models and in humans. Docetaxel (DTX), an antiproliferative chemotherapeutic agent has not been explored yet in the treatment of atherosclerosis. New Zealand white male rabbits were fed with 1% cholesterol diet throughout the 8-week experimental period to induce atherosclerosis. After 4 weeks, the animals were treated weekly with LDE-DTX (n=9) at a dose of 1mg/kg i.p. or only with LDE (Control group, n=9). We evaluated feed intake, lipid, hematological, and weight profiles during the protocol at baseline, 4 weeks and post-treatment. After euthanasia was performed morphological analysis and Western blot of the aorta. As expected, total cholesterol increased 42-fold in both groups comparing baseline to post-treatment. There was a decrease in red blood cells number in both groups but it is probably not treatment-related. There was no hepatic and renal treatment-related toxicity. The macroscopic lesion area in the aortas of LDE-DTX was approximately 80% smaller compared to Control and the morphometry of the aortic arch was 86% smaller in LDE-DTX group compared to Control group. Regarding inflammatory factors, CD68 was 64% lower in LDEDTX group comparing to Control group. MCP-1 was 84% in LDE-DTX group and TNF-alpha was 44% lower in the treated group comparing to Control group. The protein expression of IL-1beta and NFkB were about 60% lower in the LDE-DTX group as well as IL-6 that was 79% lower, both compared to Control group. The von Willebrand factor was about 30% lower in LDE-DTX group compared to Control group. The pro-apoptotic factors showed lower expression in LDE-DTX group: caspases 3 was 82% lower compared to control and caspases 9 and Bax were about 50% than Control group as well as the anti-apoptotic factor Bcl-2. The protein expression of collagen I and III were lower in LDE-DTX group. Compared to control, the protein expression of MMP-2 and MMP-9 were about 70% lower in the LDE-DTX group compared to Control group. The cell proliferation marker PCNA was 41% lower in LDE-DTX group compared to Control group. Treatment with LDE-DTX association proved to be effective since the treated rabbits had a smaller area of the atherosclerotic lesion, lower inflammation, cell death and proliferation in the aorta when compared to Control group
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Avaliação dos efeitos de antígenos de Paracoccidioides brasiliensis em células dendríticas derivadas de monócitos de pacientes com paracoccidioidomicose: expressão de moléculas de superfície, linfoproliferação e secreção de citocinas / Evaluation of Paracoccidioides brasiliensis antigens effects on monocyte-derived dendritic cells from patients with paracoccidioidomycosis: expression of surface molecules, lymphoproliferation and secretion of cytokines

Paula Keiko Sato 08 December 2015 (has links)
INTRODUÇÃO: A paracoccidioidomicose (PCM) induz uma resposta imune tipo Th1 relacionada à proteção, com imunodepressão antígeno-específica transitória. As células dendríticas (DCs) são as mais potentes apresentadoras de antígeno, porém, pouco se sabe sobre seu papel na PCM humana e sobre os efeitos do fungo em suas funções. OBJETIVO: Investigar os efeitos in vitro de antígenos de Paracoccidioides brasiliensis (P. brasiliensis) sobre as DCs derivadas de monócitos de pacientes com PCM. MÉTODOS: Foram incluídos 27 pacientes com PCM ativa (PA; com diagnóstico micológico, histopatológico ou títulos de anticorpos anti-P. brasiliensis >= 32) e 31 pacientes com PCM tratada (PT; anticorpos anti-P. brasiliensis com títulos <= 4, em duas coletas num período de 6 meses, e doença comprovada no passado pelos mesmos critérios de pacientes com PCM ativa), e de 39 indivíduos sadios (CO; não sensibilizados a antígenos de P. brasiliensis e sem anticorpos a tais antígenos fúngicos) foram geradas a partir de monócitos do sangue periférico, tratados com IL-4 e GM-CSF. As DC diferenciadas não-tratadas (nDC) ou tratadas com TNF-alfa (DC+TNF) foram estimuladas com os antígenos de P. brasiliensis: glicoproteína de 43 kDa (gp43) a 2 e 5 ug/mL (Gp2 e Gp5), e antígeno solúvel a 15 ug/mL (CFA). As moléculas de superfície CD11c, CD1a, HLA-DR, CD86, CD80 e DC-SIGN das DCs foram analisadas por citometria de fluxo e as citocinas IL-10, IL-12p40, IL-1beta e CCL18 foram dosadas nos sobrenadantes das culturas por ELISA. As DCs foram então co-cultivadas com linfócitos autólogos, medindo-se a linfoproliferação por incorporação de timidina triciada e dosando-se por ELISA os níveis de citocinas IL-10, IL-4, IFN-y e TNF-alfa foram dosadas nos sobrenadantes dessas culturas. RESULTADOS: As DCs de PA e PT apresentaram expressão de CD11c e CD1a similar à observada nas DCs de CO. No grupo PT, Gp5 induziu maior expressão de HLA-DR em comparação ao grupo PA, e o CFA aumentou o percentual de DCs CD86+. As DCs de PT, na presença de TNF-alfa, secretaram grandes quantidades de IL-12p40, especialmente frente ao CFA. Este antígeno induziu forte proliferação de linfócitos autólogos tanto de pacientes do grupo PA quanto do grupo PT, em relação ao grupo CO e às células sem CFA. Os níveis de IL-10 foram maiores no grupo PA, enquanto que os de IL-4 foram maiores no grupo PT, tanto nos co-cultivos com DCs e Gp quanto com DCs e CFA. Por outro lado, apenas o estímulo de DCs com CFA, e não com gp43, induziu altos níveis de IFN-y e TNF-alfa. CONCLUSÕES: DCs de PT tem alta expressão de HLA-DR, CD86 e DC-SIGN, altos níveis de IL-12p40 e baixos de IL-10, induzidos por CFA. DCs de PA apresentam expressão de moléculas similar às de DCs de indivíduos sadios, e baixos níveis de IL-12-p40 e IL-10. A gp43 induziu pouca linfoproliferação e baixos níveis de IFN-y e TNF-alfa nos co-cultivos de linfócitos autólogos e DCs de PT e PA. O CFA foi mais eficiente que a gp43 no estímulo de DCs PT e PA mas não de CO, ao induzir proliferação de linfócitos autólogos com aumento da secreção de IFN-y e TNF-alfa. Esses resultados, combinados aos níveis constantes de IL-10 e altas concentrações de IL-12p40, sugerem que o CFA seja melhor indutor de resposta Th1, podendo servir como alvo para pesquisas de epítopos candidatos à vacina de células dendríticas anti-P. brasiliensis. / INTRODUCTION: Paracoccidioidomycosis (PCM) induces a Th1 immune response associated with protection, with a transitory antigen-specific immunodepression. Dendritic cells (DCs) are the most potent antigen presenting cells, but little is known about their role on human PCM and the effects of fungal antigens on their functions. OBJECTIVE: To investigate the in vitro effects of Paracoccidioides brasiliensis (P. brasiliensis) antigens on monocyte-derived DCs from patients with PCM. METHODS: Twenty-seven patients with active PCM (PA; with mycological or histopathological diagnosis or antibody titles anti-P. brasiliensis >= 32) and 31 treated PCM (PT; antibody titles <= 4 on two samples within six months, and proved disease in the past by the same criteria of active PCM) and from 39 non-PCM subjects (CO; non-sensitized to P. brasiliensis antigens and without anti-fungal antigens antibodies) were included in this study and DCs were generated from peripheral blood monocytes with IL-4 and GM-CSF. Differentiated DCs were treated with TNF-alfa (DC+TNF) or left untreated (nDC) and then stimulated with P. brasiliensis antigens: 43 kDa glycoprotein (gp43) at 2 and 5 ug/mL (Gp2 and Gp5), and the cell-free antigen at 15 ug/mL (CFA). Surface molecules CD11c, CD1a, HLA-DR, CD85, CD80 and DC-SIGN were analyzed by flow cytometry and the cytokines IL-10, IL-12p40, IL-1beta and CCL18 were assayed by ELISA. DCs were cocultured with autologous lymphocytes: lymphoproliferation was measured by the incorporation of tritiated thymidine and the cytokines IL-10, IL-4, IFN-y and TNF-alfa were also assayed by ELISA. RESULTS: DCs from PA and PT groups showed similar expression of CD11c and CD1a to those of CO group. On the PT group, Gp5 induced higher expression of HLA-DR when compared to PA and CFA increased the percentage of CD86+ DCs. When stimulated with CFA, TNF-alfa -treated DCs from the PT group secreted large amounts of IL-12p40. This antigen also induced strong proliferation of autologous lymphocytes on both PA and PT groups in comparison to CO group and to unstimulated cells. Both DCs with CFA and DCs with gp43 induced high levels of IL-10 and IL-4 on the PA and PT groups, respectively. On the other hand, only DCs with CFA and not those with gp43 were able to induce high levels of IFN-y and TNF-alfa. CONCLUSIONS: CFA-stimulated DCs from treated PCM showed high expression of HLA-DR, CD86 and DC-SIGN, increased levels of IL-12p40 and low levels of IL-10. DCs from patients with active disease have expression of surface molecules similar to those of non-PCM subjects, with low levels of IL-12p40 and IL-10. Gp43 induced low lymphoproliferation and decreased levels of IFN-y and TNF-alfa in the cocultures of DC and autologous lymphocytes from PT and PA groups. CFA was more efficient than gp43 on stimulating DCs to induce proliferation of autologous lymphocytes with increased secretion of IFN-y and TNF-alfa on both PT and PA cells but not on CO. These results combined with constant levels of IL-10 and high amounts of IL-12p40 suggest that CFA may be a better inducer of Th1 immune response and a suitable target for future researches on epitopes candidates for anti-P. brasiliensis dendritic cell-based vaccines
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Um modelo estocástico de simulação da dinâmica dos queratinócitos, melanócitos e melanomas no desenvolvimento dos tumores / A stochastic model of simulation of the dynamics of keratinocytes, melanocytes and melanomas in the development of tumors

Willian Wagner Lautenschlager 17 March 2017 (has links)
Durante as últimas décadas, pesquisas em biologia do tumor com a utilização de novas técnicas de biologia molecular produziram informações em profusão, motivando e dando condições para que fossem criados novos modelos matemáticos dedicados à análise de vários aspectos de crescimento e proliferação da população celular. Alguns desses modelos têm sido dedicados à descrição e análise do regime estacionário do processo de desenvolvimento de uma população celular sob condições químicas que se consideram favorecer a aceleração ou desaceleração do crescimento da população de células tumorais. Todavia, a dinâmica temporal do crescimento de uma população de células tumorais ainda não foi analisada nesses trabalhos. Uma das dificuldades é o estabelecimento da interação entre células de múltiplos tipos que sirvam como descrição para essa dinâmica. Nosso trabalho vem preencher essa lacuna e a presente dissertação tem como objetivo a apresentação do modelo, desenvolvido por nós, de simulação da dinâmica do crescimento e proliferação celular do melanoma (câncer de baixa incidência, mas de letalidade extremamente alta) e também dos resultados obtidos através das simulações deste modelo computacional / During the last decades, tumor biology research with the use of new techniques in molecular biology resulted in a profusion of information that have given conditions and motivated the development of new mathematical models dedicated to analyzing various aspects of growth and proliferation of the cell population. Some of these models have been devoted to the description and analysis of the steady state of the development process of a cell population under chemical conditions that, in theory, promote the acceleration or deceleration of the growth of tumor cell population. However, these studies have not yet analyzed the temporal dynamics of growth of a tumor cell population. One of the difficulties is the establishment of the interaction between cells of multiple types that serve as the description for this dynamic. Our work fills this gap and this dissertation aims to present the model, developed by us, to simulate the growth dynamics and cellular proliferation of melanoma (cancer of low incidence but of extremely high lethality) and the results obtained through the simulations of this computational model
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Participação do sistema nervoso parassimpático no metabolismo energético e na proliferação celular em ilhotas pancreáticas de ratos obesos-MSG

Lubaczeuski, Camila 01 August 2013 (has links)
Made available in DSpace on 2017-07-10T14:17:01Z (GMT). No. of bitstreams: 1 Camila.pdf: 1579699 bytes, checksum: 81aed6e2676f0085056d80a67c1ae83e (MD5) Previous issue date: 2013-08-01 / The growing number of overweight and obesity has led to an increase in the number of patients with insulin resistance and diabetes mellitus type 2. MSG obese rats were glucose intolerant, insulin resistant and theirs pancreatic islets secrete more insulin in response to glucose. Subdiafragmatic vagotomy changes the response of islets to glucose and improves glucose homeostasis, supporting the hypothesis that an unbalance of autonomic nervous system with increased parasympathetic nervous system (PNS) action but a decreased sympathetic nervous system function. Studies showed that the PNS is also involved in β-cell proliferation. Therefore, we investigated of PNS participation, using a subdiafragmatic vagal denervation, upon pancreatic β-cell function and mass regulation, and the body glucose control disruption in MSG-obese rats. For this, Male Wistar rats received during the first five days of life monosodium glutamate (MSG) or saline. Subdiaphragmatic vagotomy was performed at 30 days of life. At 90 days of age, we verified static insulin secretion, pancreas morphometric, ERK expression in islets, glucose homeostasis and lipidis. The MSG treatment caused obesity at 90 days of life. MSG rats presented lower body weight and nasoanal length, increased Lee index and fat depots, normoglycemia, hyperinsulinemia, dyslipidemia, glucose intolerance and insulin resistance when compared to CTL. Vagotomy performed at 30-days of age prevented obesity, fat deposition in the liver and ameliorated glucose tolerance and insulin sensitivity in adult MVAG rats in relation to MSG rats. Islets from MSG rats secreted more insulin at stimulatory glucose concentrations than CTL islets. Histological analysis showed that pancreatic islets from MSG rats were lower with a reduction in β-cell area without modification in α-cell content when compared with CTL. Also, MSG group presented an increased number of pancreatic islets per mm2, with higher number of islets, which may contributes to the higher islet and β-cell relative mass in the MSG pancreas. These effects were associated with enhanced proliferation in MSG group. The number of MVAG pancreatic islet were less than MSG. Vagotomoy performed at 30-days of age, reduced islet and β-cell area in the pancreas from 90-days old CVAG rats. Finally, the relative islet and β-cell mass in MVAG and CVAG rats was similar to CTL. Here we verified if ERK was involved in β-cell replication in MSG rats, but presented no alteration. We demonstrate for the first time that adult MSG rats showed enhanced pancreatic β-cell proliferation which contributes to the higher islet insulin secretion in response to glucose. The vagus nerve is the main factor involved in such a process, since vagotomy performed at 30 days of age prevented islet morphological alterations in adult MVAG rats. Possibly this increase PNS activity in MSG endocrine pancreas is responsible to hyperinsulinemia that enhanced fat storage, damaged glucose homeostasis and insulin action in MSG obesity. / O crescente número de pessoas com sobrepeso e obesidade tem levado ao aumento no número de pacientes com resistência à insulina (RI) e portadores do Diabetes mellitus tipo 2. Ratos obesos MSG são intolerantes à glicose (Gli), RI e suas ilhotas pancreáticas secretam mais insulina em resposta à concentrações de Gli. A vagotomia subdiafragamática altera a responsividade das ilhotas à Gli e melhora a homeostase glicêmica nestes animais, sugerindo um desbalanço do sistema nervoso autonômico, com aumento do tônus parassimpático e redução do simpático. Estudos demonstram que o sistema nervoso parassimpático (SNP) possui efeito na proliferação das células β-pancreáticas. Desta forma, investigamos a participação do SNP, através da vagotomia subdiafragmática, no metabolismo energético e na proliferação das ilhotas e de células β-pancreáticas de ratos obesos-MSG. Para isto, ratos Wistar machos receberem durante os cinco primeiros dias de vida glutamato monossódico (grupo MSG) ou salina (grupo CTL). A vagotomia subdiafragmática foi realizada aos 30 dias de vida formando os grupos MVAG e CVAG. Aos 90 dias, verificamos a secreção estática de insulina, homeostase glicêmica e lipídica, morfometria do pâncreas e conteúdo proteico da ERK nas ilhotas. Ratos MSG apresentaram redução do peso corporal e comprimento nasoanal, aumento do índice de Lee e acúmulo de gordura, normoglicêmia, hiperinsulinemia, dislipidemia, intolerância à Gli e RI comparados aos CTL. A vagotomia realizada aos 30 dias de vida preveniu obesidade, acúmulo de gordura no fígado e melhorou a tolerância à Gli e a sensibilidade à insulina em ratos MVAG adultos em relação aos ratos MSG. As ilhotas dos animais MSG secretaram mais insulina quando estimulada pela Gli, em relação aos animais CTL. As análises histológicas mostram que as ilhotas pancreáticas dos animais MSG são menores com redução da área das células β sem alteração nas células α em relação aos CTL. O grupo MSG apresenta um aumento do número das ilhotas por mm2, que pode estar contribuindo com o aumento da massa relativa das ilhotas e das células β. Esse efeito está associado ao aumento da proliferação no grupo MSG. O número de ilhotas foi menor nos MVAG em relação aos MSG. A vagotomia realizada aos 30 dias de vida reduziu a área das ilhotas e das células β aos 90 dias de vida nos animais CVAG. Finalmente, a massa relativa das ilhotas e da células β no MVAG e CVAG foram similares ao CTL. Verificamos se a ERK estava envolvida na proliferação das células β nos ratos MSG, porém não apresentaram alterações desta proteína. Pela primeira vez demonstramos que ratos MSG apresentam aumento da proliferação das células β que contribui com o aumento da secreção de insulina em resposta à Gli. O nervo vago é o principal fator envolvido neste processo, visto que a vagotomia realizada aos 30 dias de vida preveniu as alterações morfológicas das ilhotas nos ratos MVAG adultos.
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Efeitos do ultra-som terapêutico na integração de enxertos de pele total em coelhos. / Effects of the therapeutic ultrasound on the integration of full-thickness skin graft in rabbits.

Amancio, Adriana da Costa Gonçalves 20 February 2003 (has links)
O ultra-som terapêutico é um recurso físico muito empregado como coadjuvante na promoção do reparo tecidual. Neste trabalho, foi estudada a influência do ultra-som terapêutico na integração dos enxertos de pele total num modelo experimental em coelhos. Foram utilizados 20 coelhos adultos, fêmeas, nos quais foram realizadas cirurgias de enxerto autógeno de pele total nas regiões escapulares, pela ressecção de dois retalhos quadrados de pele de 2 cm de lado, invertendo sua posição, o enxerto retirado do lado direito sendo colocado na área receptora esquerda e vice-versa. O enxerto do lado direito era submetido ao tratamento efetivo com o ultra-som (3 MHz, 0,5 W/cm2, 5 minutos) e o enxerto do lado esquerdo, a tratamento placebo, iniciado no 3o dia pós-operatório e aplicado diariamente por sete dias. Os animais eram sacrificados no 11o dia pós-operatório e os enxertos, ressecados com uma margem de segurança, para análise histopatológica, com cortes de 5 µm. Foram obtidos cortes histológicos corados com técnicas específicas (Tricrômico de Gomori, PCNA e Picrosirius) e analisados ao microscópio de luz, sendo realizada a contagem das células em proliferação e dos vasos neoformados e a morfometria das áreas da epiderme e derme. Os resultados mostraram um significativo aumento no número de células em proliferação na epiderme e vasos neoformados na camada reticular da derme, mas isto não implicou em uma diferença entre as áreas da epiderme e derme, nos enxertos irradiados e não irradiados. Concluímos que o ultra-som terapêutico induz alterações morfológicas nos processos biológicos, como proliferação celular da camada germinativa da epiderme e neoangiogênese, envolvidos na integração de enxertos de pele total, com um potencial de aplicação clínica em humanos. / Therapeutic ultrasound is a widely used co-adjuvant physical mean to promote tissue repair. In the present investigation, the influence of therapeutic ultrasound on the integration of full-thickness skin graft was studied in rabbits. Twenty female adult rabbits were used, two 2x2 cm square-shaped full-thickness skin grafts being obtained from both scapular regions and swapped, the one cut out on the right being placed on the left and vice-versa. The graft on the right was effectively irradiated with the therapeutic ultrasound (3 MHz, 0,5 W/cm2, 5 minutes) for seven days beginning on the third postoperative day. The graft on the left was submitted to a sham irradiation. The animals were killed on the 11th day and the grafted areas were resected (graft + safety margin) for histologic examination by means of 5 µm-thick sections alternatively stained with Gomori's trichrome, PCNA and Picrosirius and examined on the light microscope. Eider proliferating cells and new blood vessels were counted, as well as the epidermic and dermic areas were measured. The results showed a significant increase in the number of epidermic proliferating cells and new blood vessels, but this did not imply any difference between the epidermic and dermic areas between irradiated and non-irradiated grafts. We conclude that the therapeutic ultrasound induces morphologic alterations in the biologic processes, as epidermic germinative layer cell proliferation and neo-angiogenesis, involved in the integration of full-thickness skin grafts and this has a potential for clinical use in humans.

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