Navegando por Palavras-chave "Quimioprevenção"

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    Atividade quimioprotetora do extrato de maçã na carcinogênese bucal quimicamente induzida pela 4-nitroquinolina 1-óxido em ratos
    (Universidade Federal de São Paulo (UNIFESP), 2014-09-23) Ribeiro, Flavia Andressa Pidone [UNIFESP]; Ribeiro, Daniel Araki [UNIFESP]; http://lattes.cnpq.br/9969803499258672; http://lattes.cnpq.br/6162191034018572; Universidade Federal de São Paulo (UNIFESP)
    Head and neck cancers represent 10% of malignant tumors, and approximately 40% of them are located in the oral cavity. In Brazil oral cancer, is considered the sixth most frequent types in men and the eight most common in women. In recent decades, there has been a significant increase in interest in food classified as nutraceuticals, because they are able to prevent diseases. The aim of the study was to evaluate the chemoprotective potential of apple extract following rat tongue carcinogenesis induced by 4 nitroquinoline 1 oxide. A total of 30 male Wistar rats eight weeks-old were distributed into five groups, as follows: Group 1- negative control (no treatment); Group 2 - received food and 4NQO at a dose of 20 ppm in drinking water for 8 weeks and treated with apple extract at 1 mL dose by gavage daily during the first four weeks; Group 3 - received food and 4NQO at a dose of 20 ppm in drinking water for 8 weeks and treated with apple extract at 1 mL dose by gavage between the 5th and 8th week daily; Group 4 - received food and water ad libitum and apple extract by gavage for 8 consecutive weeks; Group 5 - positive control that received food and 4NQO at a dose of 20 ppm in drinking water for 8 weeks daily. Histopathology, gene expression of COX-2, TNF-alpha, eNOS, iNOS, caspase-3, cytochrome c, MnSOD, Cu/ZnSOD and catalase were assessed. Histopathological analysis showed that the apple extract was able to reduce hyperplastic, and dysplastic lesions found in the groups 2 and 3 when compared to group 4. Furthermore, a decrease in expression of COX-2 and TNF-alpha was noticed to groups 2 and 3 when compared to group 5. There was a significant increase in caspase-3 in the expression of Cu / Zn and Mn genes, and cytochrome c in groups exposed to 4NQO and treated with apple extract. In summary, these results suggest that the apple extract was able to exert some chemoprotective effect during experimental oral carcingenesesis a result of antioxidant, anti-inflammatory and apoptotic activities.
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    Chemoprevention by celecoxib in reflux-induced gastric adenocarcinoma in Wistar rats that underwent gastrojejunostomy
    (Sociedade Brasileira para o Desenvolvimento da Pesquisa em Cirurgia, 2009-06-01) Rocha, Frederico Theobaldo Ramos; Lourenço, Laércio Gomes [UNIFESP]; Jucá, Mário Jorge; Costa, Valéria; Leal, Antenor Teixeira; Federal University of Alagoas Department of Surgery; Universidade Federal de São Paulo (UNIFESP); UFAL Department of Surgery; UNCISAL Pathology Department
    PURPOSE: To evaluate chemoprevention by celecoxib in cases of reflux-induced gastric adenocarcinoma, in Wistar rats that underwent gastrojejunostomy. METHODS: Sixty male Wistar rats of average age three months underwent surgery and were distributed into three groups: group 1, exploratory laparotomy; group 2, gastrojejunostomy; and group 3, gastrojejunostomy and daily celecoxib administration. After 53 weeks, the animals were sacrificed. Changes in the mucosa of the gastric body of group 1 and in the gastrojejunal anastomosis of groups 2 and 3, observed in histopathological and immunohistochemical examinations, were compared. All statistical analyses were performed using Epi-Info®, version 3.4.3. RESULTS: Comparison between groups 2 and 3 relative to the presence of adenocarcinoma showed a statistically significant difference (p=0.0023). Analysis of the association between groups 2 and 3 relative to COX-2 expression also showed a statistically significant difference (p=0.0018). CONCLUSION: Celecoxib had an inhibiting effect on gastric carcinogenesis induced by enterogastric reflux in an animal model.
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    Isotretinoína oral em dose baixa versus tretinoína tópica na prevenção de queratoses actínicas em pacientes imunocompetentes: estudo clínico randomizado e comparativo
    (Universidade Federal de São Paulo (UNIFESP), 2016-05-31) Ianhez, Mayra [UNIFESP]; Bagatin, Edileia [UNIFESP]; http://lattes.cnpq.br/6478900066830476; http://lattes.cnpq.br/2315002761719798; Universidade Federal de São Paulo (UNIFESP)
    Introduction: Chronic photoexposure can generate actinic keratosis and damage to the surrounding normal skin (field cancerization), which can evolve to skin cancer. Currently, the treatment of actinic keratosis addresses not only the destruction of individual lesions (using methods such as liquid nitrogen cryosurgery, electrocoagulation, trichloroacetic acid, and shaving), but also the treatment of field cancerization (using drugs such as 5-fluorouracil, imiquimod, ingenol mebutate, oral and topical retinoids, chemical peelings, and photodynamic therapy). Most studies involving retinoids have as purpose and primary outcome the prevention of nonmelanoma skin cancer. Therefore, few data are available about their use for the treatment of actinic keratosis. Oral and topical retinoids can be used for prevention and treatment of multiple actinic keratoses and field cancerization, especially in association with sunscreen and liquid nitrogen cryosurgery. Objectives: The primary objective of this research was to evaluate the clinical, histopathological, and immunohistochemical effects on the epidermis and dermis of the studied drugs for the treatment of multiple actinic keratoses of the face and forearms in immunocompetent patients. The secondary objectives were: 1) to evaluate the tolerability and safety of the medications; 2) to demonstrate the impact of the treatments on quality of life; 3) to investigate the reproducibility of lesion count as a parameter of efficacy; 4) to verify the role of cryosurgey associated to daily use of sunscreen in the control of actinic keratosis. Methods: This is an open, randomized, propective, and comparative clinical trial, including 61 participants, from 50 to 75 years of age, from both genders, with 5 to 60 visible and/or palpable actinic keratoses on the face and forearms. At the beginning (T0) and after 120 days (T120), all participants underwent liquid nitrogen cryosurgery to treat their actinic keratoses. Posteriorly, they were randomized in two treatment groups: 30 took oral isotretinoin, at the dose of 10 mg/day (ISO group), and 31 used 0.05% topical tretinoin cream every other night (TRE group), for 6 months (T300). All the subjects used SPF 60 sunscreen during the whole study period. At the beginning of the randomization (T120) and at the end of the study (T300), two biopsies were performed in the left forearm. The efficacy was evaluated using clinical (number of actinic keratoses) and histopathological parameters (hematoxilin-eosin and Weigert-Van Gieson staining, the latter for elastic fibers), as well as immunohistochemical markers of carcinogenesis (proteins p53, Bcl-2, and Bax) before and after the treatments. The safety evaluation included the report and observation of side effects and biochemical laboratory tests for the participants of the ISO group. Results: A decrease in the number of actinic keratoses related to liquid nitrogen cryosurgery and the use of SPF 60 sunscreen was observed between T0 and T120 (-39%) and to the treatments for field cancerization with oral isotretinoin (-33%) and topical tretinoin (-23%), cryosurgery and SPF 60 sunscreen between T120 and T300. The histopathological and immunohistochemical findings demonstrated: thinning of the stratum corneum and reduction of p53 and Bax expression between T120 and T300. Thickening of the basal to the granular layer and increased expression of Bcl-2 protein were observed in both groups. No modifications were found in the elastic tissue. In general, the treatment groups did not differ (p > 0.1). Only slight side effects were observed in both groups, except severe xerophthalmia in one patient of the ISO group. Between T120 and T180, the levels of total cholesterol and triglycerides increased in 76% and 61% of the participants, respectively, and this increase was around 30% of the initial value, returning to normal in T300 without the need to change or interrupt the treatment. Conclusion: Both low-dose oral isotretinoin and 0.05% topical tretinoin cream improved clinical, histopathological, and immunohistochemical parameters in patients with multiple actinic keratoses and field cancerization, without differences between them. The therapeutic choice of retinoids for field cancerization should take into consideration the patient?s profile, particularly in relation to the risk of side effects.
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    Perfil dos contatos de pacientes com tuberculose
    (Universidade Federal de São Paulo (UNIFESP), 2013) Rodrigues, Priscilla Moraes [UNIFESP]; Rodrigues, Denise do Socorro da Silva [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    Estimause que um terco da populacao mundial esteja infectado pelo bacilo. Sabe-se que 10% dos adultos infectados pelo M. tuberculosis adoecerao, 5% logo apos a primoinfeccao e os outros 5% por reativacao do bacilo ou nova exposicao. O risco de adoecimento e maior nos dois primeiros anos apos a infeccao, e aproximadamente 90% dos casos de adoecimento dos contatos ocorre neste periodo. O presente estudo prospectivo teve como objetivo avaliar as caracteristicas epidemiologicas e demograficas dos contatos de pacientes com tuberculose e analisar os fatores de risco para infeccao latente e progressao para o adoecimento por tuberculose acompanhada por um periodo de dois anos no Instituto Clemente Ferreira em São Paulo. Foram analisados 339 contatos dos 140 casos indices. Realizaram a prova tuberculinica (PT) 233 adultos e 106 criancas. A taxa de ILTB entre os contatos foi de 64% e existiu uma forte associacao entre infeccao latente e a positividade da baciloscopia do caso indice. Nao se observou correlacao entre a incidencia de infeccao latente ou adoecimento entre os contatos com os outros fatores estudados (grau de convivencia, grau de parentesco, doencas associadas, tempo de contato com o caso indice bacilifero, tabagismo e etilismo). O tratamento da infeccao latente pelo Mtb foi fator de maior relevancia na progressao para tuberculose ativa entre contatos. A taxa de adoecimento entre todos os contatos foi de 5% e de 8,3% entre os reatores a prova tuberculinica. Entre todos os contatos que receberam tratamento profilatico nenhum adoeceu. Dos 87 contatos que nao receberam tratamento preventivo, 21% adoeceram. Das 11 criancas em que nao foi indicado o tratamento da infeccao latente, tres adoeceram. Entre os contatos adultos dos 76 que nao receberam tratamento para ILTB, 15 adoeceram. O tratamento da tuberculose latente e o diagnostico precoce da tuberculose ativa sao fundamentais para bloquear a transmissao que sustenta a epidemia da TB dessa forma instituir o tratamento precoce da doenca. Neste estudo observamos que 100% daqueles que receberam quimioprofilaxia nao adoeceram o que reforca a importancia do acompanhamento dos contatos e tratamento da infeccao latente nessa populacao
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    Quimioprevenção pelo celecoxibe no adernocarcinoma gástrico, induzido por refluxo, em ratos Wistar, submetidos à gastrojejunostomia
    (Universidade Federal de São Paulo (UNIFESP), 2008) Rocha, Frederico Theobaldo Ramos [UNIFESP]; Lourenço, Laércio Gomes [UNIFESP]
    Objetivo: Avaliar a quimioprevenção pelo celecoxibe no adenocarcinoma gástrico, induzido por refluxo, em ratos Wistar, submetidos à gastrojejunostomia. Métodos: Sessenta ratos machos Wistar, com média de idade de 3 meses, peso médio de 300g foram operados e distribuídos em 3 grupos: Grupo 1, constituído de 10 animais que foram submetidos à laparotomia exploradora. Grupo 2, constituído de 25 animais que foram submetidos à gastrojejunostomia. Grupo 3, constituído de 25 animais que foram submetidos à gastrojejunostomia e que tomaram celecoxibe (10 mg/kg/dia). Após urn período de 53 semanas de observação, os animais foram sacrificados. As alterações microscópicas na mucosa do corpo gástrico dos animais do grupo 1 e na anastomose gastrojejunal dos animais dos grupos 2 e 3, observadas no exame histopatológico (Hematoxilina-Eosina) e Imuno-histoquímica, foram comparadas. 0 estudo estatí8stico (freqüências das variáveis e análises de associações entre os grupos 2 e 3) foi realizado pelo programa Epi Info®, versão 3.4.3. Resultados: Nos animais do grupo 1 não foram observadas lesões inflamatórias e metaplásicas, displásicas ou neoplásicas (adenocarcinomas). Nos animais do grupo 2, observaram-se lesões inflamatórias e metaplásicas em 12 casos (48%), displásicas em 3 casos (12%) e adenocarcinomas em 10 casos (40%). Nos animais do grupo 3, observaram-se lesões inflamatórias e metaplásicas em 24 casos (96%) e urn adenocarcinoma (4%). Todos os adenocarcinomas eram do tipo bem diferenciado. Observou-se expressão para ciclooxigenase-2 em 9 de 11 casos (81,8%) nos adenocarcinomas, em 1 de 3 casos (33,3%) nas displásias e em 4 de 36 casos (11,1%) nas lesões inflamatórias e metaplásicas. Na análise de associação entre os grupos 2 e 3 com relação a presença de adenocarcinoma gástrico, observou-se uma diferença estatística significante (p=0,0023). Na análise de associação entre os grupos 2 e 3 com relação à expressão da ciclooxigenase-2, também se observou diferença estatística significante (p=0,0018). Na análise de associação entre a expressão da ciclooxigenase-2 e 0 adenocarcinoma gástrico nos grupos 2 e 3, também se observou uma diferença estatística significante entre os adenocarcinomas que expressaram ciclooxigenase-2 em relação aos que não expressaram (p=0,000034). Conclusão: 0 celecoxibe teve efeito inibidor da carcinogênese gástrica, induzida pelo refluxo êntero-gástrico em modelo animal..