RESUMEN
UNLABELLED: Experimental colitis induced by acetic acid has been used extensively as a model for intestinal inflammatory disease. Colonic tissue lesions of intestinal inflammatory disease patients seem to be related to the increased local production of pro-inflammatory cytokines (IL-1, IL-6, TNF-alpha, and IFN-gamma). PURPOSE: To assess the cytokine expression pattern identified through immunohistochemistry in colonic mucosa after experimental colitis induced by acetic acid and establish the relationship between this pattern and the presence of macroscopic lesions. MATERIALS AND METHODS: Adult male Wistar rats (n = 39) were divided at random into 4 groups: NC45 and NC24 (control without colitis; sacrificed at 45 minutes and 24 hours, respectively); and WC45 and WC24 (with experimental colitis induced by acetic acid; sacrificed at 45 minutes and 24 hours, respectively). Macroscopic and microscopic alterations in colonic tissue were evaluated, and cytokine expression was assessed through immunohistochemistry. RESULTS: After 24 hours, IL-1 expression was greater in the groups with colitis when compared to the groups without colitis. IL-4 expression was higher in the WC45 group. There was an increase in both INF-gamma and IL-6 related to the presence of necrosis of the colonic mucosa in the groups with colitis for both periods evaluated. CONCLUSION: The immunohistochemical technique was efficient for the analysis of various cytokine expressions in the colonic tissue. There was an increase in the IL-1 pro-inflammatory cytokines as well as in IL-6 and IFN-gamma associated with the presence of colonic necrosis. Experimental colitis induced by acetic acid is a useful model for the development of studies assessing the role of cytokines in the inflammation of mucosa as well as anti-cytokine therapies.
Asunto(s)
Colitis/metabolismo , Citocinas/biosíntesis , Mucosa Intestinal/metabolismo , Ácido Acético , Animales , Colitis/inducido químicamente , Colitis/patología , Modelos Animales de Enfermedad , Mucosa Intestinal/patología , Masculino , Necrosis , Ratas , Ratas Wistar , Índice de Severidad de la EnfermedadRESUMEN
O modelo de colite experimental induzida por ácido acético (CEAA) vem sendo extensamente utilizado em estudos sobre doenças inflamatórias intestinais (DII). Lesões no tecido colônico em portadores de DII parecem estar relacionados à produção local aumentada de citocinas pró-inflamatórias (IL-1, IL-6, TNF-a e IFN-g). OBJETIVO: Avaliar o padrão de expressão de citocinas identificadas por imunohistoquímica em tecido colônico após CEAA e relacioná-lo à presença de lesões macroscópicas. MATERIAL E MÉTODOS: Ratos machos Wistar adultos (n=39) foram submetidos ou não à CEAA e sacrificados para retirada do tecido colônico em dois períodos distintos, perfazendo 4 grupos aleatórios: SC45 e SC24 (sem colite; sacrifício 45 minutos e 24 horas, respectivamente); CC45 e CC24 (com colite; sacrifício 45 minutos e 24 horas, respectivamente). Avaliaram-se alterações macro e microscópicas do cólon e sua expressão de citocinas foi avaliada por imunohistoquímica. RESULTADOS: Após 24 horas, a expressão de IL-1 foi maior no grupo com colite, em relação ao sem colite. IL-4 foi mais expressa no grupo CC45. Houve aumento de INF-g e IL-6, relacionados à presença de necrose da mucosa colônica, nos grupos com colite, em ambos os períodos avaliados. CONCLUSÃO: A técnica de imunohistoquímica foi eficiente para a análise da expressão de citocinas na mucosa colônica. Houve aumento da expressão das citocinas pró-inflamatórias IL-1 e de IL-6 e IFN-g associado à presença de necrose colônica. A CEAA é um bom modelo para o desenvolvimento de estudos destinados a avaliar o papel das citocinas na inflamação da mucosa e terapias anti-citocinas.
Asunto(s)
Animales , Masculino , Ratas , Colitis/metabolismo , Citocinas/biosíntesis , Mucosa Intestinal/metabolismo , Ácido Acético , Colitis/inducido químicamente , Colitis/patología , Modelos Animales de Enfermedad , Mucosa Intestinal/patología , Necrosis , Ratas Wistar , Índice de Severidad de la EnfermedadRESUMEN
OBJECTIVES: The purpose of this study was to evaluate whether flow pattern and resistive index (RI) are useful parameters for distinguishing benign from malignant thyroid follicular neoplasms (FNs). METHODS: Eighty-six thyroid nodules that underwent sonographically guided fine-needle aspiration and were diagnosed as cases of FN were evaluated by power and duplex Doppler sonography. Pathologic correlation was available for all nodules. The flow pattern seen via power Doppler examination was ranked for each nodule on a scale of 0 to 4, in increasing flow order. For each nodule, the RI value was considered the average of 1 to 3 values obtained with different flow signals. RESULTS: Ten nodules (11.63%) were malignant (3 follicular carcinomas, 5 follicular variants of papillary carcinoma, and 2 papillary carcinomas). Fourteen nodules (16.27%) were adenomas, and 62 (72%) were non-neoplastic nodules. The average RI in non-neoplastic nodules was 0.588 (P < .001, chi(2) test): 0.662 in adenomas and 0.763 in malignant nodules. None of the nodules had flow pattern type 0. Flow patterns 1 and 2 (peripheral flow only or predominantly) were present in 58 non-neoplastic nodules (93.5%), 10 adenomas (71.4%), and 2 malignant nodules (20%). Flow pattern type 3 (predominantly central flow) was present in 7 malignant nodules (70%), 4 adenomas (28.6%), and 4 non-neoplastic nodules (6.5%). Only 1 nodule, a papillary carcinoma, had flow pattern type 4 (internal flow only). CONCLUSIONS: In FNs, there were significant positive associations between predominantly central flow and malignancy and between predominantly peripheral flow and benign disease (P < .0001, Fisher exact test). However, power Doppler characteristics could not be used to rule out malignancy because 20% of malignant nodules had predominantly peripheral flow. For predicting malignancy, an RI cutoff of 0.75 had good accuracy, specificity, and negative predictive value but had low sensitivity and positive predictive value (respectively, 91%, 97%, 92%, 40%, and 67%). Resistive index values in non-neoplastic nodules were lower than in adenomas and malignant nodules (P < .001, chi(2) test).