Denise Gonçalves Priolli

Analysis of Oxidative DNA Damage in Patients with Colorectal Cancer

PURPOSE The aim of this study was to measure the levels of oxidative DNA damage in cells isolated from the colon mucosa in patients with colorectal cancer and to compare normal and neoplastic tissues and make correlations with anatomopathologic variables. PATIENTS AND METHODS Thirty-three patients with colorectal adenocarcinoma were studied. The oxidative DNA damage was evaluated by means of the alkaline version of the comet assay. RESULTS For all the patients studied, it was found that the cells obtained from the neoplastic tissue presented oxidative DNA damage greater than in the cells from normal tissue. The cells isolated from the neoplastic mucosal tissue of the colon presented significantly greater mean extent of DNA strand breakage than the cells isolated from normal tissue. Additionally, the patients at earlier stages of the Dukes and TNM classifications presented higher levels of oxidative damage than those at more advanced stages. CONCLUSION Assessment of the levels of oxidative damage at the different stages of colorectal carcinogenesis is of great interest because it enables evaluation of the effectiveness of antioxidant substances that could be used as preventive measures against the initial oxidative aggressive action on the colonic mucosa.

Tissue quantification of neutral and acid mucins in the mucosa of the colon with and without fecal stream in rats

PURPOSE To quantify the intensity of the expression of neutral and acids mucins in mucosa of the colon with and without fecal stream and to correlate this with the duration of fecal transit diversion. METHODS Thirty male Wistar rats were subjected to fecal transit deviation in the left colon by a proximal colostomy and a distal mucous fistula. The animals were divided into three experimental groups, according to whether sacrificing would be performed six, 12 or 18 weeks after surgery. The expression of neutral and acid mucins was evaluated using the histochemical techniques of Periodic Acid Schiff and Alcian Blue, respectively. The tissue mucins expression was quantified by computer-assisted image analysis software (NIS-Elements) in the segments with and without fecal stream. Students paired t test was used to compare the quantities of mucins in colon with or without fecal stream and variance between the experimental groups by ANOVA and Newman-Keuls post-test, establishing level of signification of 5% (p<0.05). RESULTS There were significant decreased quantities of acid and neutral mucins in the colon without transit, compared with the colon with fecal stream, independent of the duration of exclusion. There was increased expression of neutral mucins in the colon with fecal stream after 12 and 18 weeks of exclusion. There was no increase in the expression of acid mucins in the colon with transit as the duration of fecal transit exclusion progressed. There was increased production of acid mucins in the animals submitted to diversion of the fecal stream for 18 weeks, compared with those subjected to diversion for 6 and 12 weeks. In the colon without fecal stream, there was increased expression of neutral mucins after 12 and 18 weeks of exclusion. CONCLUSIONS Deviation of the fecal stream decreased the expression of acid and neutral mucins in the segments without fecal transit, compared with segments with transit. Regardless of the reduced expression of acid and neutral mucins in the segments without fecal stream, their tissue expression increased with increasing duration of intestinal deviation.

Evaluation by computerized morphometry of histopathological alterations of the colon wall in segments with and without intestinal transit in rats

PURPOSE To evaluate histopathological alterations of the colon wall in segments with and without intestinal transit, by computer-assisted imaging, and to correlate these with the length of time diversion. METHODS Thirty male Wistar rats were subjected to intestinal transit diversion by a proximal colostomy and distal mucosa fistula. The animals were divided into three experimental groups according to how long after the initial surgical procedure they were sacrificed: six, twelve and eighteen weeks. Colon segments with and without transit were subjected to histopathological study. The variables colon crypt length, mucosal ulceration, muscle layer thickness of the muscularis mucosa, submucosa and muscularis propria, vascular congestion, number of caliciform cells, inflammatory grade and degree of inflammation, comparing the two colon segments in the different experimental groups were studied. Intestinal crypt length, muscle layer thickness of the mucosa, submucosa and muscularis propria and caliciform cells were measured by computer-assisted imaging method. Mean equality, variance analysis and correlation tests were used in the statistical analysis, and the significance level was set at 5%. RESULTS Comparison between segments with and without transit showed that the latter presented reduced length of colon crypts and increased muscle layer thickness of the muscularis mucosa, submucosa and muscularis propria. There were greater quantities of ulceration of the mucosal and greater degree of inflammation with increasing time without transit. Mucosal ulceration, submucosal vascular congestion, increased thickness of the submucosal and muscularis propria layers, presence of caliciform cells, inflammatory infiltrate and inflammatory grade correlated significantly with the length of time without transit. CONCLUSIONS Histological alterations occurred in all layers of the colon wall, in the segments without intestinal transit. Ulcerations in the intestinal mucosa, increased number of caliciform cells, greater vascular congestion of the submucosal layer and inflammatory reaction were related to increasing length of time without transit.

Quantification by computerized morphometry of tissue levels of sulfomucins and sialomucins in diversion colitis in rats

PURPOSE To quantify the intensity of sulfomucin and sialomucin expression in the colon mucosa, by means of computer-assisted image processing, comparing segments with and without fecal stream and correlating with the duration of fecal transit exclusion. METHODS Forty-five Wistar rats were subjected to diversion of the fecal stream in the left colon by means of constructing a proximal colostomy and distal mucosal fistula. They were distributed randomly into three experimental groups of 15 animals, of which 10 were subjected to colon diversion (experimental subgroup) and five were only subjected to laparotomy, without colon diversion (control subgroup). The three experimental groups were formed according to the sacrifice date, which was to be performed six weeks after the surgical procedure (Group A), 12 weeks (Group B) and 18 weeks (Group C). The sulfomucin and sialomucin expression in the colon mucosa was evaluated using the histochemical technique of high iron diamine-alcian blue (HID-AB). The tissue expression was quantified for each animal, in the segments with and without fecal stream, at a location where there were four complete contiguous crypts in two random fields, with the aid of the computer-assisted image analysis software. The final value was taken to be the mean reading from the two fields selected, in the segments with and without fecal stream. To compare the expressions of the two mucin subtypes in the segments with and without fecal stream, the paired Student t test was used. To analyze variance according to duration of exclusion, ANOVA with the Newman-Keuls post-test was used, setting the significance level at 5% (p<0.05). RESULTS There were significant reductions in tissue sulfomucin and sialomucin content in the colon without fecal stream, independent of the duration of exclusion considered. There was increased tissue sulfomucin content and decreased tissue sialomucin in the segments without fecal stream, with increasing duration of exclusion. CONCLUSIONS Diversion of the fecal transit decreased the tissue sulfomucin and sialomucin content in the segments without fecal stream. Notwithstanding the reduction in the levels of both subtypes of acid mucin in the segments without fecal stream, there was increased tissue sulfomucin content and decreased tissue sialomucin with increasing duration of intestinal diversion.

Metastatic lymph node ratio as an independent prognostic variable in colorectal cancer: study of 113 patients

BackgroundIn patients with colorectal cancer, involvement of the lymph nodes is one of the most important prognostic factors. The aim of this study was to determine the independent prognostic value of the lymph node ratio (LNR), that is the relationship between the involved and examined lymph nodes, in patients with colorectal cancer.MethodsIncluded in the study were 113 patients with colorectal adenocarcinoma. The patients were divided into three groups according to the proportion of involved lymph nodes: LNR-0, when there was no lymph node involvement; LNR-1, when there was involvement of up to 20% of the examined lymph nodes, and LNR-2, when there was involvement of 21% or more of the examined nodes. The relationship between lymph node ratio, the number of lymph nodes removed, and the number of lymph nodes involved by cancer was determined. The 5-year survival was evaluated using the Kaplan-Meier test.ResultsThere was a significant difference in 5-year overall between patients in the different LNR groups (p=0.009). Patients in the LNR-0 group had a 5-year overall survival greater than 80%, while those in the LNR-1 and LNR-2 groups had 5-year overall survival rates less than 60% and 40%, respectively. Multivariate analysis demonstrated that the LNR is an independent prognostic variable in 5-year overall survival (p=0.009).ConclusionThe results showed that the LNR can be considered an independent prognostic variable in overall survival of patients with colorectal cancer.

Inflammatory alterations in excluded colon in rats: A comparison with chemically induced colitis

Abstract Diversion colitis occurs commonly in the large bowel remnant after diversion of the fecal stream. Several experimental models of colitis have been described, but none examine the inflammatory alterations that can occur in experimentally defunctioned colons. This characterization could be useful in understanding pathophysiological aspects of diversion colitis, and in developing future therapeutic strategies. Thus, we evaluated the temporal inflammatory alterations in the defunctioned colon of rats by analyzing the histological results, infiltrating neutrophils, pro-inflammatory markers such as cyclooxygenase (COX)-2 and inducible nitric oxide synthase (iNOS), and DNA damage in isolated colonocytes. We compared the obtained data with those from hapten-induced colitis. The experimental diversion of the colon fecal stream induces diversion colitis characterized by an early inflammatory process with increased neutrophil infiltrate, and COX-2 and iNOS expression that resembles, in some aspects, the inflammatory characteristics of chemically induced colitis. After acute inflammation resolution, there was an increase in COX-2 and iNOS expression and the presence of lymphoid follicular hyperplasia and ulcerations, suggesting that diversion colitis can be experimentally established and useful for studying different pathophysiological aspects of this condition.

Methotrexate is effective in reactivated colitis and reduces inflammatory alterations in mesenteric adipose tissue during intestinal inflammation.

Mesenteric white adipose tissue hypertrophy and modifications in adipocytokine production are described features of Crohns disease. Experimentally, mesenteric white adipose tissue alterations, associated with intestinal inflammation, can be induced in a model of reactivated colitis by repeated administration of intrarectal trinitrobenzenosulfonic acid (TNBS) in ethanol solution. Crohns disease patients refractory to corticosteroid treatment are frequently treated with methotrexate; however, there is no information regarding the drugs effect on adipose tissue alterations and in a reactivated colitis experimental model. Thus, we evaluated the effect of methotrexate upon mesenteric WAT alterations and inflammatory features in experimental colitis in rats. Colitis status was evaluated by macroscopic score, histopathological analysis, myeloperoxidase activity, TNF-alpha and IL-10 expression, as well as iNOS and TLR-4 expression in colon samples. The adipose tissue alterations were assessed by TNF-alpha, IL-10, leptin and adiponectin production, as well as by macrophage infiltration evaluation. Methotrexate exerts an anti-inflammatory activity in experimental reactivated colitis by regulating the shift from Th1 to Th2 cytokines, reducing TNF-alpha and improving IL-10 production. Additionally, methotrexate reduces other inflammatory parameters in the colon, such as iNOS and TLR-4 expression. In mesenteric white adipose tissue, methotrexate treatment reduces the production of pro- and anti-inflammatory adipocytokines as well as macrophage infiltration, suggesting that immunosuppressant drugs diminish adipose tissue inflammatory alterations associated with intestinal inflammation.

Cuidados no fim da vida: o ensino médico no Brasil

BACKGROUND: There is importance in analysis of tech-learning in the medical schools that allows identify opportunities of improvement in end-of-life care education. PURPOSE: The aim of this study is describe end-of-care teaching attitudes and practices in undergraduate medical curriculum in Brazil as reported by the course coordinators. METHOD: A questionnaire about end-of-life care was applied on 179 course coordinators of medical schools in Brazil. RESULTS: Fifty-eight coordinators participated (32,4%). Most of them (96,6%) considered end-of-life care education as very important. Seventy-tree percent believes that the time to teaching about palliative care in their curriculum is insufficient. The priority given to education in palliative care is considered insufficient or inexistent in 50,9% of cases. The small number of faculty expertise is one of barriers to incorporate end-life-care in the medical schools curriculum. CONCLUSION: Attitudes and practices suggest that end-life-care education has limitations in undergraduate medical Brazilian curriculum. Even so the current coordinators believe its importance still is given little priority to the education of this subject in Brazil.

Miíase vulvar: relato de caso

Myiasis located in the vulva is a rarely described disease. The objective of the present report is to describe a case of vulvar myiasis due to larvae of Cochliomyia hominivorax. A 77-year-old woman with precarious hygienic habits presented pain, pruritus and secretions with a fetid smell in the genital region for 10 days. Gynecological examination demonstrated an ulcerated lesion in the labium majus of the vulva measuring six centimeters that extended to the mons pubis and was found to be filled with larvae. The patient progressed favorably after removal of the larvae, surgical debridement and daily dressings. Fourteen days after the debridement, she was submitted to skin flap rotation, with good local scar formation. Two months after the intervention, she remained asymptomatic. Vulvar myiasis must be considered in the differential diagnosis of infectious diseases of the vulva in patients with precarious hygienic habits.

Edema quantification by computerized morphometry as an evaluation parameter for the resistance of colon anastomoses

OBJETIVO: Verificar a validade do emprego da morfometria computadorizada, como metodo de analise quantitativa da interferencia do edema na cicatrizacao das anastomoses colicas. METODOS: Foram utilizados 45 ratos, Wistar, femeas adultas, divididas em tres grupos de 15 animais segundo a data do sacrificio ter sido realizada no primeiro, segundo e setimo pos-operatorio. Cada grupo foi subdividido em grupo principal, constituido de 10 animais, onde alem da analise morfometrica computadorizada quantitativa do edema na camada submucosa foi verificada a resistencia da anastomose colica a pressao de explosao e um grupo controle, constituido de cinco animais, onde se estudou isoladamente a quantificacao do edema. RESULTADOS: Os resultados encontrados pelo metodo morfometrico computadorizado constataram que existe reducao de 7%, em valores percentuais, da presenca do edema durante a primeira semana pos-operatoria e confirmaram que existe relacao inversa, estatisticamente significante (p< 0,001), entre a presenca de edema e a resistencia a pressao de explosao da anastomose. CONCLUSAO: O emprego da morfometria computadorizada e metodologia fidedigna, rapida, objetiva e de baixo custo na quantificacao de edema nas anastomoses colicas.