Quality indicators in colonoscopy: observational study in a supplementary health system

Purpose: Colorectal cancer is responsible for 9.4% of cancer deaths, and low polyp detection rate and cecal intubation rate increase the risks of interval colorectal cancer. Despite several population studies that address colonoscopy quality measures, there is still a shortage of these studies in Latin America. The aim of this study was to assess quality indicators in colonoscopy, enabling future strategies to improve colorectal cancer prevention. Methods: An observational retrospective study, in which all colonoscopies performed in 11 hospitals were evaluated through a review of medical records. Information such as procedure indication, colorectal polyp detection rate, cecal intubation rate, quality of colonic preparation, and immediate adverse events were collected and analyzed. Results: In 17,448 colonoscopies performed by 86 endoscopists, 57.9% were in patients aged 50 to 74 years old. Colon preparation was adequate in 94.4% procedures, with rates of cecal intubation and polyp detection of 94 and 36.6%, respectively. Acute adverse events occurred in 0.2%. In 53.9%, high-definition imaging equipment was used. The procedure location, colon preparation and high-definition equipment influenced polyp detection rates (p < 0.001). Conclusions: The extraction and analysis of electronic medical records showed that there are opportunities for improvement in colonoscopy quality indicators in the participating hospitals.

Ureterostomias cutânea e colônica em suínos: avaliação da exequibilidade das técnicas / Cutaneous ureterostomies in pigs: technical feasibility assessment

O aumento da expectativa de vida dos animais de companhia favorece a ocorrência de casos de câncer, como o de bexiga. O objetivo da presente pesquisa foi avaliar a exequibilidade da técnica de ureterostomia cutânea em suínos após a realização da cistectomia total, quando comparada à técnica de ureterostomia colônica, assim como detectar e caracterizar possíveis complicações transoperatórias. Foram utilizados 20 animais, distribuídos em dois grupos. Todos foram submetidos à cistectomia radical e, em seguida, à ureterostomia cutânea ou colônica. A exequibilidade das técnicas foi avaliada. Observou-se o tamanho da incisão, o tempo de diérese, de realização da derivação urinária e o tempo de síntese, estimou-se a perda sanguínea e o grau de dificuldade na realização dos procedimentos de preparo dos ureteres, o preparo do sítio de ureteroanastomose e a realização da ureteroanastomose em si. Os resultados indicam que a ureterostomia cutânea apresentou maior eficiência quando comparada à colônica nos quesitos perda de sangue, tamanho da incisão realizada e facilidade de realização da anastomose. Já a ureterocolostomia apresentou melhor resultado referente à execução do preparo ureteral. Assim, concluiu-se que ambas as técnicas podem ser indicadas como derivações urinárias viáveis e que a escolha dependerá de fatores intrínsecos ao cirurgião e ao paciente.(AU)

Increased life expectancy of pets favors the occurrence of cancer, such as the urinary bladder ones. The aim of this study was to evaluate the feasibility of cutaneous ureterostomy technique in pigs after the total cystectomy compared to the technique of colonic ureterostomy, as well as detect and characterize possible intraoperative complications. For that, 20 pigs were used, divided into two groups. All patients underwent radical cystectomy and then the cutaneous or colonic ureterostomies. The technical feasibility was assessed during the procedures. The procedures compared were: the incision size, dieresis time, realization of urinary diversion and the synthesis time. Also, the estimated blood loss and the degree of difficulty in performing the preparation procedures of the ureters, ureteroanastomose site preparation and ureteroanastomose itself were compared. The results indicate that performing cutaneous ureterostomy was better than the colonic ureterostomy in relation to blood loss, incision size, and anastomosis performance. In contrast, ureterocolonostomy showed better results on the implementation of ureteral preparation. Thus, it was concluded that both techniques can be indicated as viable urinary diversions and the choice will depend on factors intrinsic to the surgeon and the patient.(AU)

Ureterostomias cutânea e colônica em suínos: avaliação da exequibilidade das técnicas / Cutaneous ureterostomies in pigs: technical feasibility assessment

O aumento da expectativa de vida dos animais de companhia favorece a ocorrência de casos de câncer, como o de bexiga. O objetivo da presente pesquisa foi avaliar a exequibilidade da técnica de ureterostomia cutânea em suínos após a realização da cistectomia total, quando comparada à técnica de ureterostomia colônica, assim como detectar e caracterizar possíveis complicações transoperatórias. Foram utilizados 20 animais, distribuídos em dois grupos. Todos foram submetidos à cistectomia radical e, em seguida, à ureterostomia cutânea ou colônica. A exequibilidade das técnicas foi avaliada. Observou-se o tamanho da incisão, o tempo de diérese, de realização da derivação urinária e o tempo de síntese, estimou-se a perda sanguínea e o grau de dificuldade na realização dos procedimentos de preparo dos ureteres, o preparo do sítio de ureteroanastomose e a realização da ureteroanastomose em si. Os resultados indicam que a ureterostomia cutânea apresentou maior eficiência quando comparada à colônica nos quesitos perda de sangue, tamanho da incisão realizada e facilidade de realização da anastomose. Já a ureterocolostomia apresentou melhor resultado referente à execução do preparo ureteral. Assim, concluiu-se que ambas as técnicas podem ser indicadas como derivações urinárias viáveis e que a escolha dependerá de fatores intrínsecos ao cirurgião e ao paciente.(AU)

Increased life expectancy of pets favors the occurrence of cancer, such as the urinary bladder ones. The aim of this study was to evaluate the feasibility of cutaneous ureterostomy technique in pigs after the total cystectomy compared to the technique of colonic ureterostomy, as well as detect and characterize possible intraoperative complications. For that, 20 pigs were used, divided into two groups. All patients underwent radical cystectomy and then the cutaneous or colonic ureterostomies. The technical feasibility was assessed during the procedures. The procedures compared were: the incision size, dieresis time, realization of urinary diversion and the synthesis time. Also, the estimated blood loss and the degree of difficulty in performing the preparation procedures of the ureters, ureteroanastomose site preparation and ureteroanastomose itself were compared. The results indicate that performing cutaneous ureterostomy was better than the colonic ureterostomy in relation to blood loss, incision size, and anastomosis performance. In contrast, ureterocolonostomy showed better results on the implementation of ureteral preparation. Thus, it was concluded that both techniques can be indicated as viable urinary diversions and the choice will depend on factors intrinsic to the surgeon and the patient.(AU)

Analysis of gene expression EGFR and KRAS, microRNA-21 and microRNA-203 in patients with colon and rectal cancer and correlation with clinical outcome and prognostic factors

Purpose: To evaluate the expression of EGFR, KRAS genes, microRNAs-21 and 203 in colon and rectal cancer samples, correlated with their age at diagnosis, histological subtype, value of pretreatment CEA, TNM staging and clinical outcome. Methods: Expression of genes and microRNAs by real time PCR in tumor and non-tumor samples obtained from surgical treatment of 50 patients. Results: An increased expression of microRNAs-21 and 203 in tumor samples in relation to non-tumor samples was found. There was no statistically significant difference between the expression of these genes and microRNAs when compared to age at diagnosis and histological subtype. The EGFR gene showed higher expression in relation to the value of CEA diagnosis. The expression of microRNA-203 was progressively lower in relation to the TNM staging and was higher in the patient group in clinical remission. Conclusions: The therapy of colon and rectum tumors based on microRNAs remains under investigation reserving huge potential for future applications and clinical interventions in conjunction with existing therapies. We expect, based on the exposed data, to stimulate the development of new therapeutic possibilities, making the treatment of these tumors more effective.(AU)

Podem as bactérias ácido lácticas probióticas apresentarem efeito antitumoral em modelo animal de câncer de cólon? Uma revisão da literatura / Can probiotic acid lactic bacteria submit antitumor effect in animal model of colon cancer? A review of the literature

O Câncer de cólon é um dos tipos mais comuns de câncer no mundo e a segunda principal causa de morte relacionada a esta doença em países desenvolvidos. Até 75% dos casos estão associados com a alimentação, indicando que uma pessoa pode reduzir o seu risco simplesmente através de modificação na dieta. Estudos em animais demonstram que várias cepas de bactérias ácido lácticas protegem contra o câncer de cólon em roedores, embora os dados em humanos sejam limitados e conflitantes. O objetivo deste estudo foi investigar a eficácia das bactérias ácido lácticas no tratamento e redução do câncer de cólon em modelo animal. Foram realizadas buscas sistemáticas em bases de dados eletrônicas alcançando 1079 artigos relacionados, entretanto apenas 6 artigos foram eleitos de acordo com os critérios de elegibilidade para análise. Todos os artigos avaliados apresentaram resultados satisfatórios quanto à inibição do câncer de cólon em ratos e camundongos ao utilizarem cepas predominantemente do gênero Lactobacillus. Este estudo pode responder a hipótese de que as bactérias ácido lácticas apresentam efeito preventivo e antitumoral contra o câncer de cólon.(AU)

Colon cancer is one of the most common types of cancer in the world and the second leading cause of death related to the disease in developed countries. Up to 75% of cases are associated with eating, indicating that a person can reduce their risk simply through dietary modification. Studies in animals show that various strains of lactic acid bacteria protect against colon cancer in rodents although data in humans are limited and conflicting. The aim of this study was to investigate the efficacy of acid lactic bacteria in the treatment and reduction of colon cancer in animal models. Systematic searches were conducted in electronic databases reaching 1079 related articles, only six articles were elected according instead of to the eligibility criteria for analysis. All reviewed articles showed satisfactory results on the inhibition of colon cancer in rats and mice when using predominantly Lactobacillus strains. This study can answer hypothesis that acid lactic bacteria has antitumor effect against colon cancer.(AU)

Podem as bactérias ácido lácticas probióticas apresentarem efeito antitumoral em modelo animal de câncer de cólon? Uma revisão da literatura / Can probiotic acid lactic bacteria submit antitumor effect in animal model of colon cancer? A review of the literature

O Câncer de cólon é um dos tipos mais comuns de câncer no mundo e a segunda principal causa de morte relacionada a esta doença em países desenvolvidos. Até 75% dos casos estão associados com a alimentação, indicando que uma pessoa pode reduzir o seu risco simplesmente através de modificação na dieta. Estudos em animais demonstram que várias cepas de bactérias ácido lácticas protegem contra o câncer de cólon em roedores, embora os dados em humanos sejam limitados e conflitantes. O objetivo deste estudo foi investigar a eficácia das bactérias ácido lácticas no tratamento e redução do câncer de cólon em modelo animal. Foram realizadas buscas sistemáticas em bases de dados eletrônicas alcançando 1079 artigos relacionados, entretanto apenas 6 artigos foram eleitos de acordo com os critérios de elegibilidade para análise. Todos os artigos avaliados apresentaram resultados satisfatórios quanto à inibição do câncer de cólon em ratos e camundongos ao utilizarem cepas predominantemente do gênero Lactobacillus. Este estudo pode responder a hipótese de que as bactérias ácido lácticas apresentam efeito preventivo e antitumoral contra o câncer de cólon.(AU)

Colon cancer is one of the most common types of cancer in the world and the second leading cause of death related to the disease in developed countries. Up to 75% of cases are associated with eating, indicating that a person can reduce their risk simply through dietary modification. Studies in animals show that various strains of lactic acid bacteria protect against colon cancer in rodents although data in humans are limited and conflicting. The aim of this study was to investigate the efficacy of acid lactic bacteria in the treatment and reduction of colon cancer in animal models. Systematic searches were conducted in electronic databases reaching 1079 related articles, only six articles were elected according instead of to the eligibility criteria for analysis. All reviewed articles showed satisfactory results on the inhibition of colon cancer in rats and mice when using predominantly Lactobacillus strains. This study can answer hypothesis that acid lactic bacteria has antitumor effect against colon cancer.(AU)

Malignant metastatic insulinoma in a dog

Background: Insulinomas are tumors of the pancreatic islet beta cells that secreting insulin. They are malignant neoplasms and rarely seen in dogs. Because insulinomas secrete excessive insulin and hypoglycemia occur. The most common clinical symptoms are seizures, extreme weakness, and other neurological abnormalities. The tumors typically release insulin episodically, with clinical signs being seen intermittently as a result. These are most often associated with prolonged starvation or prolonged periods of exertion. Insulinoma occurs most often in middle-aged and older dogs, averaging nine years in age. They affect both sexes and are more likely in larger breeds. The most commonly afflicted breeds are German Shepherds, Irish Setters, Boxers, Golden Retrievers and Terriers. Case: In this study, a case of malignant insulinoma with multiorgan metastasis in a 7-year-old hunting dog that brought to the clinic with complaints of constipation and inappetence were evaluated by clinical, cytological, histopathological and immunohistochemical findings. Owner stated that the animal suffers from constipation for 4 days, but no vomitus or nervous symptoms were present. Clinical efforts not solved the constipation. For to the definitive diagnosis the dog decided to underwent laparotomy. After a midline abdominal approach multiple whitish, hard and irregular metastatic tumoral masses were[...]

Malignant metastatic insulinoma in a dog

Background: Insulinomas are tumors of the pancreatic islet beta cells that secreting insulin. They are malignant neoplasms and rarely seen in dogs. Because insulinomas secrete excessive insulin and hypoglycemia occur. The most common clinical symptoms are seizures, extreme weakness, and other neurological abnormalities. The tumors typically release insulin episodically, with clinical signs being seen intermittently as a result. These are most often associated with prolonged starvation or prolonged periods of exertion. Insulinoma occurs most often in middle-aged and older dogs, averaging nine years in age. They affect both sexes and are more likely in larger breeds. The most commonly afflicted breeds are German Shepherds, Irish Setters, Boxers, Golden Retrievers and Terriers. Case: In this study, a case of malignant insulinoma with multiorgan metastasis in a 7-year-old hunting dog that brought to the clinic with complaints of constipation and inappetence were evaluated by clinical, cytological, histopathological and immunohistochemical findings. Owner stated that the animal suffers from constipation for 4 days, but no vomitus or nervous symptoms were present. Clinical efforts not solved the constipation. For to the definitive diagnosis the dog decided to underwent laparotomy. After a midline abdominal approach multiple whitish, hard and irregular metastatic tumoral masses were[...](AU)

Serological under expression of microRNA-21, microRNA-34a and microRNA-126 in colorectal cancer

PURPOSE: This paper describes the ability of miRNA value predict oncological outcomes in CRC patients and correlates to clinical and pathologic variables. METHODS: We prospectively analyzed the serological expression of microRNA-21, microRNA-34a, and microRNA-126 in 37 stage II - IV CRC patients and correlate to seven fit counterparts. Serological microRNAs were extracted using the miRNeasy Mini Kit(r) (Qiagen, Hilden, Germany). Quantification of microRNAs was performed using TaqMan Master Mix(r) reagent (Applied Biosystems, USA). RESULTS: We obtained serological underexpression microRNA-21, microRNA-34a, and microRNA-126 in CRC group. However, miRNAs serological values do not impact prognosis. Furthermore, miRNAs was not influenced by CEA values, TNM staging, and histological subtype. CONCLUSION: Despite lower expression of miR-21, miR-34a and miR-126 in the CRC group, no association with poor prognosis was found.(AU)

Comparative evaluation of oncologic outcomes in colon cancer

PURPOSE: In this paper we report clinical variables on colon cancer series. Oncological outcomes were compared to low-income and high-income countries. METHODS: We analysed a prospective database of 51 colon cancer patients submitted to primary tumor resection between 2010 and 2011, showing clinical variables and oncologic outcomes. RESULTS: R0 resection obtained in 80.4%, 21.6% of patients was TNM stage IV, and only 13.7% showed TNM stage I. Disease-free survival was 32 months, overall survival was 46 months, and the tumoral recurrence rate was 9.8%. Univariate analysis showed association of serum CEA levels 5 ng/dl (p= 0.004), presence of metastasis at diagnosis (p= 0.012), compromised surgical margins (p 0.001) and poorer tumor differentiation (p= 0.041) to death. Multivariate analysis identified compromised surgical margins as an independent risk factor for death due to colon cancer (P=0.003; odds ratio=0.36; 95% confidence interval=0.004-0.33). Nowadays, 62.7% of patients are alive. CONCLUSION: Recurrence rate, disease-free survival and overall survival was similar to those observed in more developed countries. Serum CEA levels 5 ng/dl, the presence of metastasis at diagnosis, compromised surgical margins and poorer tumor differentiation were associated with death. A compromised surgical margin was the only independent risk factor for death.(AU)

Secondary bile acids effects in colon pathology. Experimental mice study

To assess whether deoxycholic acid (DOC) and lithocholic acid (LCA) administered in a period of six months in a concentration of 0.25% may have a carcinogenic role in mice colon. The study used C57BL6 female mice divided into four groups. The control group received a balanced diet and the others received diets supplemented with 0.25% DOC, 0.25% LCA and 0.125% DOC+0.125% LCA, respectively. After euthanasia, the lesions found in the resected gastrointestinal tracts were stained with hematoxylin-eosin and examined microscopically. No gastrointestinal tract changes were observed in the control group, while hyperplastic Peyer's patches in the small intestine, flat adenomas with mild dysplasia and chronic colitis at the level of the colon were found in all three test groups. The colonic lesions prevailed in the proximal colon. The highest number of flat adenoma lesions (8), hyperplasia of Peyer's patches (25) and chronic colitis (2) were found in mice fed with diet and LCA. Precancerous or cancerous pathological lesions could not be identified. Instead, adenomatous colonic injuries occurred in a shorter period of time (six months), compared to the reported data.(AU)

Effect of probiotics on the development of dimethylhydrazine-induced preneoplastic lesions in the mice colon

PURPOSE: To determine the effect of probiotics on the development of chemically induced (1, 2-dimethylhydrazine) colonic preneoplastic lesions, in mice. METHODS: The animals were divided into five groups. The control group was injected with carcinogen alone and the other groups also received probiotics (1- Lactobacillus delbrueckii UFV-H2b20; 2- Bifidobacterium animalis var. lactis Bb12; 3- L. delbrueckii UFV-H2b20 plus B. animalis var. lactis Bb12; and 4- Saccharomyces boulardii) administered orally in drinking water throughout fourteen weeks. RESULTS: Consumption of lactobacilli and bifidobacteria alone resulted in a significant reduction of the total number of aberrant crypt foci (55.7% and 45.1%, respectively). Significant reduction in the number of these small foci (<3 aberrant crypts) was only observed in the group treated with lactobacilli (52.2%) in comparison to control group. The number of larger foci (>3 aberrant crypts) crypts had no significant reduction. CONCLUSION: L. delbrueckii UFV-H2b20 and B. animalis var. lactis Bb12 administered alone protect colonic preneoplastic lesions in mice, while the combined treatment of these bacteria and the administration of S.boulardii were not effective in reducing such colonic lesions.(AU)

Ponderal behavior of rats fed an omegas 3, 6 and 9 enriched diet submitted to colon carcinogenesis induced by azoxymethane

PURPOSE: To assess weight changes in rats fed diets with different ratios of omegas 3, 6 and 9 submitted to colonic carcinogenesis induced by Azoxymethane (AOM). METHODS: Sixty rats with three weeks of life were distributed into five groups of specific diets containing 12 animals each: GI- Standard diet without adminstration of AOM, GII- Standard diet with adminstration of AOM; GIII- Hyperlipidic diet with adminstration of AOM; GIV-Normolipidic diet with adminstration of AOM; GV- Hypolipidic diet with adminstration of AOM. The weight and food intake of each group were assessed four times in each week throughout the experiment until euthanasia at 36th week. RESULTS: GI and GII had no significant difference in weight. GI showed a significant increase when compared to GIII, GIV and GV. GII also showed a significant increase when compared to GIII, GIV and GV. When comparing intake of GI as compared to GII no significant difference was found, however such groups had higher intake than groups III, IV and V. There were found no difference in weight when comparing amoung rats with and without cancer within each groups: GII, GIII, GIV and GV. CONCLUSIONS: Diets rich in omega 3, 6 and 9 reduced food intake and weight. Rats with colorectal cancer had no decrease in weight as compared to those without this condition in the same group.(AU)

A novel model of distal colon cancer in athymic mice / Novo modelo de câncer de cólon distal em camundongos atímicos

PURPOSE: The present a novel adenocarcinoma model in athymic mice. METHODS: Seven athymic mice were used. Colon diversion and distal fistula were made. Adenocarcinoma cells were inoculated in the submucosa of fistula. Tumor growth was monitored daily. Scintigraphy with 99mTc-MIBI was performed to identify the tumor. RESULTS: The model of distal colon cancer is feasible. Tumor detection was possible by both, macroscopically and molecular imaging. All resections demonstrated poorly differentiated tumors. Colon obstruction occurred in one case, similarly to evolution in human tumors of distal colon. CONCLUSION: The proposed model of distal colon cancer is feasible, allows for easy monitoring of tumoral growth by both, macroscopically and molecular imaging, and is suitable for studying the evolution of tumor with implementation of cytotoxic therapy in vivo.(AU)

OBJETIVO: Apresentar novo modelo de adenocarcinoma distal em camundongos atímicos. MÉTODOS: Foram utilizados sete camundongos atímicos. Desvio do cólon distal e fístula foram feitas. Células de adenocarcinoma foram inoculadas na submucosa da fístula. O crescimento do tumor foi monitorado diariamente. Cintilografia com 99mTc-MIBI foi realizada para identificar o tumor. RESULTADOS: O modelo de câncer de cólon distal é viável. Detecção do tumor foi possível macroscopicamente e por imagem molecular. Todas as ressecções demonstraram tumores pouco diferenciados. Obstrução do cólon ocorreu em um caso, de forma semelhante à evolução em tumores humanos do cólon distal. CONCLUSÃO: O modelo de câncer do cólon distal proposto é viável, permite a monitorização fácil do crescimento tumoral macroscopicamente e por imagem molecular, sendo adequado para o estudo da evolução de tumor com aplicação de terapia citotóxica in vivo.(AU)

Effect of a hyperlipidic diet rich in omegas 3, 6 and 9 on aberrant crypt formation in rat colonic mucosa / Efeito de uma dieta hiperlipídica rica em ômegas 3, 6 e 9 na formação de criptas aberrantes em mucosa cólica de ratos

PURPOSE: To determine whether a hypercaloric and hyperlipidic diet enriched with polyunsaturated fatty acids influences the formation of aberrant crypt foci (ACF) in colonic mucosa of Wistar rats treated with azoxymethane (AOM). METHODS: At eight weeks of life, the rats were assigned to four groups: Group I―standard diet (STD) not treated with AOM; Group II―hypercaloric and hyperlipidic diet (FED), not treated with AOM; Group III―STD, treated with AOM; Group IV―FED, treated with AOM. At 16 weeks, the animals were injected intraperitoneal with 0.9 percent saline solution (Group I and II) or AOM at 15mg/Kg (Groups III and IV) once a week for two weeks. Fifteen weeks later, the animals were euthanized. RESULTS: FED promoted weight gain in Groups II and IV compared to Groups I and III, respectively. The groups did not differ with regard to the total number of ACF. The Chi-square test revealed no predominance of the presence of foci with <4 crypts. However, foci with ≥5 crypts were proportionally more prevalent in Group III than in Group IV (p=0.043). CONCLUSION: The administration of polyunsaturated fatty acids did not interfere with the formation of aberrant crypt foci, but reduced ACF multiplicity, exercising an attenuating effect on carcinogenesis.(AU)

OBJETIVO: Determinar se uma dieta hipercalórica, hiperlipídica, rica em ácidos graxos poliinsaturados (FED) tem influência na formação de focos de cripta aberrante (FCA) em mucosa cólica de ratos Wistar expostos ao azoximetano (AOM). MÉTODOS: Com oito semanas de vida, os ratos foram distribuídos em quatro grupos: Grupo I: Dieta padrão (SD) sem AOM; Grupo II: FED, sem AOM; Grupo III: SD, com AOM; Grupo IV: FED com AOM. Com 16 semanas, os animais dos grupos I e II receberam injeções intraperitoneais de solução salina 0,9 por cento, enquanto os dos grupos III e IV receberam AOM na dose de 15mg/Kg de peso, 1 vez por semana por duas semanas. Quinze semanas após, os animais foram mortos. RESULTADOS: FED promoveu aumento de peso nos grupos II e IV em relação aos grupos I e III. Não houve aumento significante no número total de FCA entre os grupos. Em relação à multiplicidade das criptas por FCA, o teste do qui-quadrado mostrou que não houve predominância da presença <4 criptas por foco. Contudo, focos ≥5 criptas foram proporcionalmente mais prevalentes no grupo III que no grupo IV (p=0,043). CONCLUSÃO: Os ácidos graxos poliinsaturados não interferem na formação de focos de cripta aberrante, contudo reduz sua multiplicidade, exercendo efeito atenuador na carcinogênese.(AU)

Optimization of visibility and quantification of aberrant crypt foci in colonic mucosa in Wistar rats / Otimização da visibilidade e quantificação de focos de criptas aberrantes em mucosa cólica de ratos Wistar

Purpose: Test immersion of microscopy samples in water as an aid to visualizing and quantifying aberrant crypt foci (ACF) in rat colon mucosa. Methods: Carcinogenesis was induced with azoxymethane in Wistar rats kept on a conventional diet or a hypercaloric diet containing unsaturated fat. Fifteen weeks after induction, colon samples were retrieved and fixated in a 10 percent formaldehyde solution. The samples were divided into segments (distal, middle, proximal) and stained with 1 percent toluidine blue. The technique tested in the study consisted of immersing microscopy samples in distilled water in order to eliminate the problem of light reflection known from conventional microscopy. Results: When samples were immersed in water during microscopy, significantly more ACF could be visualized in all colon segments than with the conventional method proposed by Bird. Conclusion: Immersing microscopy samples in water aids the visualization and quantification of aberrant crypt foci in rat colon mucosa fixed in formaldehyde.(AU)

Objetivo: Otimizar a visibilização de focos de criptas aberrantes (FCA) em mucosa cólica de ratos Wistar. Métodos: Colo de rato Wistar, sob diferentes dietas e submetidos a iniciação de carcinogênese pelo azoximetano há 4 meses, foram previamente lavados, abertos e fixados em solução de formalina a 10 por cento por 24 horas. Após serem corados em azul de toluidina a 1 por cento, foram divididos em segmentos distal, médio e proximal e imersos em água destilada para quantificação de FCA. Resultados: No método de imersão foi visibilizado maior quantidade de focos de criptas aberrantes em todos os segmentos cólicos, com diferença significante, quando comparado com o método de Bird. Conclusão: O método de imersão otimiza a visibilização e quantificação de focos de criptas aberrantes em mucosa cólica (ratos Wistar) fixada em solução de formalina a 10 por cento.(AU)

Sodium butyrate does not decrease the evolution of precancerous lesions in rats / Butirato de sódio não diminui a evolução de lesões pré-neoplásicas em ratos

PURPOSE: To evaluate the preventive effect of sodium butyrate in the appearance of aberrant crypt foci (ACF) in rats after induction with the carcinogen 1,2-dimethylhydrazine (DMH). METHODS: Forty Wistar rats were separated into four groups (n=10) distributed as follows: control 1, control 2, butyrate 1 and butyrate 2. The groups control 1 and butyrate 1 remained under experimentation for 4 weeks, while the groups control 2 and butyrate 2 remained for 8 weeks. In the first four weeks, the animals of the control groups received water ad libitum and the animals of the butyrate groups received a sodium butyrate solution (3.4 percent) ad libitum. Injections of the drug 1,2-dimethylhydrazine were applied during the two first weeks of the experiment in all the animals, concurrently with the application of sodium butyrate. The large intestine of the animals was removed, for the analysis of the ACF and of the content of polyamines. The animal feces were collected for the analysis of the SCFA profile. RESULTS: The spermidine presented a higher concentration in the group butyrate 2 in comparison to the group control 2. There was a significant difference in the concentration value (µmol/mL) of acetate in comparison to the groups control 2 and butyrate 2. CONCLUSION: The use of sodium butyrate together with the induction of colorectal cancer was not effective in the prevention of the disease progression.(AU)

OBJETIVO: Avaliar o efeito preventivo do butirato de sódio no surgimento de focos de cripta aberrante (FCA) em ratos após a indução com o carcinógeno 1,2-dimetilhidrazina. MÉTODOS: Quarenta ratos foram divididos em quatro grupos, com dez animais em cada. Os grupos controle 1 e butirato 1 ficaram em experimentação por 4 semanas e os grupos controle 2 e butirato 2 por oito semanas. Nas primeiras quatro semanas, os animais dos grupos controle receberam água ad libitum e os animais dos grupos butirato receberam solução de butirato de sódio (3,4 por cento) ad libitum. Em todos os animais foram aplicadas quatro injeções subcutâneas da droga 1,2-dimetilhidrazina nas duas primeiras semanas, concomitante a administração do butirato de sódio. Foi retirado o intestino grosso dos animais, para análise dos FCA e do teor de poliaminas. As fezes dos animais foram recolhidas para análise do perfil de AGCC. RESULTADOS: A espermidina apresentou maior concentração no grupo butirato 2 em relação ao grupo controle 2. Foi encontrada diferença significativa no valor da concentração de acetato quando comparado os grupos controle 2 e butirato 2. CONCLUSÃO: A utilização do butirato de sódio concomitante à indução do câncer colorretal não se mostrou efetiva na prevenção da progressão da doença.(AU)

Apoptotic effects of inositol hexaphosphate on biomarker Itpr3 in induced colon rat carcinogenesis / Efeito de apoptose do inositol hexafosfato no marcador biológico Itpr3 em carcinogênese induzida de colo em ratos

PURPOSE: To study the effect of the modulation of inositol hexaphosphate (IP6) in the biological immunohistochemistry expression of cellular signaling marker apoptosis, in model of carcinogenesis of colon induced by azoxymethane (AOM). METHODS: Wistar rats (N=112) distributed in 4 groups (n=28): Control; B, AOM (5 mg kg-1, 2x, to break week 3); C, IP6 (in water 1 percent, six weeks); D, IP6+AOM. Weekly euthanasia (n=7), from week three. Immunohistochemistry of ascendant colon with biological marker inositol 1,4,5 triphosphate receptor type III (Itpr3). Quantification of the immune-expression with use of computer-assisted image processing. Analysis statistics of the means between groups, weeks in groups, groups in weeks, and established significance when p<0.05. RESULTS: One proved significant difference between groups in the expression of Itpr3, p<0.0001; with Itpr3 reduction of BxD group, p<0.001. CONCLUSION: Inositol hexaphosphate promotes modulation of biological markers with reduction of Itpr3 in carcinogenesis of colon.(AU)

OBJETIVO: Estudar os efeitos da modulação do inositol hexafosfato (IP6) na expressão imunoistoquímica de marcador biológico de sinalização celular de apoptose, em modelo de carcinogênese induzida pelo azoximetano (AOM). MÉTODOS: Ratos Wistar (N=112) distribuídos em 4 grupos (n=28): A, controle; B, AOM (5 mg Kg-1, 2x, a partir semana 3); C, IP6 (em água a 1 por cento, seis semanas); D, IP6+AOM. Eutanásia semanal (n=7), a partir de semana três. Imunoistoquímica de colo ascendente com marcador biológico inositol 1,4,5 trisphosphate receptor type III (Itpr3). Quantificação da imunoexpressão com uso de processamento imagem assistida computador. Análise estatística da expressão média entre grupos, semanas em grupos e grupos em semanas, e estabelecido significância quando p<0.05. RESULTADOS: Evidenciou-se diferença significante entre grupos na expressão de Itpr3, p<0.0001; com diminuição Itpr3 de grupo BxD, p<0.001. CONCLUSÃO: O inositol hexafostato promove a modulação de marcador biológico com diminuição Itpr3 em carcinogênese de colo.(AU)

Assessment of angiogenesis expression and its relationship with prognosis of colorectal cancer by conventional and computer-assisted histopathological image analysis / Investigação da expressão da angiogênese e sua relação com o prognóstico do câncer colorretal pela análise convencional e informatizada da imagem histopatológica

PURPOSE: To quantify the degree of angiogenesis by conventional method (microvessel density, MVD) and computerized method (endothelial area, EA), and to evaluate their relationships with the prognosis of patients operated on for colorectal adenocarcinoma. METHODS: Tumoral angiogenesis was studied by means of an immunohistochemical technique, using CD 34, on 126 patients; to quantify the angiogenesis, MVD (defined as number of microvessels per mm²) and EA measurement (defined as the area occupied by EA in the microscope field). A computerized method, IMAGELab software was utilized to quantify endothelial area. RESULTS: The mean number of microvessels was 128.6 MV/mm² (SD = 44.5) and the mean EA was 4.3 percent (SD = 2.1). The Pearson method demonstrated a low correlation coefficient between MVD and EA (r = 0.429). No relationship between MVD and EA was observed with regard to relapse-free interval and overall survival. CONCLUSION: The histological analysis of angiogenesis expression in patients with colorectal adenocarcinoma can be performed either by computer-assisted image analysis of endothelial area or by conventional microvessels counting. Both methods did not show any significant relationship between these angiogenesis parameters with relapse-free interval and overall survival.(AU)

OBJETIVO: Quantificar a intensidade da angiogênese pelo método convencional (densidade microvasal, DMV) e pelo método informatizado, área endothelial (AE) e avaliar a sua correlação com o prognóstico de doentes operados por adenocarcinoma colorretal. MÉTODOS: A angiogênese tumoral foi investigada por meio de técnica imuno-histoquímica, utilizando-se CD-34, em 126 doentes; para quantificar a angiogênese, a microdensidade vascular, definida como o número de microvasos por mm² e a medida da área endotelial, definida como a área ocupada pelo endotélio vascular identificada no campo microscópico foram empregadas. Um programa computadorizado, o IMAGELab foi empregado para a quantificação da área endothelial. RESULTADOS: A media do número de microvasos foi de 128,6 MV/mm ² (d esvio padrão de 44,5). O método do coeficiente de Pearson demonstrou uma baixa correlação entre a DMV e a AE (r=0,429). Nenhuma correlação entre a DMV e AE com o intervalo livre de doença e tempo global de sobrevida foi observada. CONCLUSÃO: A análise histológica da expressão angiogênica em doentes com adenocarcinoma colorretal pode ser realizada tanto da forma informatizada, na quantificação da área endotelial, como pela convencional, na contagem dos microvasos. Ambos métodos não demonstraram relação estatisticamente significante entre estes parâmetros de angiogênese e o intervalo livre de doença e a sobrevida global.(AU)

Wound healing and colon carcinogenesis. Enhancing effects of skin wounding on development of colon tumors induced by 1,2 Dimethylhydrazine in the rat

This study demonstrates the tumor promoting effect at a distant site of skin wounding, in a model of colon carcinogenesis induced by 1,2 dimethylhydrazine (DMH) in the rat. Six-week-old male Wistar rats were given subcutaneous injections of DMH, 20mg/kg, or saline, once a week, for eight weeks. One week after the last DMH injection the animals received a full thickness skin wound in their dorsal skin and the wound was left open to heal by second intention. Control and DMH-treated rats, with or without skin wounds were killed at the 12th week, just after healing of the skin wound was complete. The colons were removed and divided into proximal and distal parts. Each segment was rolled as "Swiss roll"and processed for histology. The incidence, distribution and morphology of the colon tumors was recorded. The total number of tumors in the colonic mucosa and the number of tumors per rat was significantly higher in the skin-wounding DMH- treated group than in the unwounded group. In the histopathological analysis of the colon the number of poorly differentiated mucin-secreting carcinomas was 6-fold in the skin-wounding DMH-treated group than in the unwounded group and the majority of tumors were located near to lymphoid aggregates. The present results suggest that wound healing enhances tumor development at a distant site, such as the colon, and this effect seems to be related to tumor histology.

Este estudo foi desenvolvido com a finalidade de investigar a possível influência do processo de cicatrização sobre o desenvolvimento neoplásico à distância, em um modelo experimental de carcinogênese do colon induzido pela 1,2 dimetil-hidrazina ( DMH). Ratos Wistar machos receberam injeções semanais de DMH ( 20mg/Kg, via subcutânea) ou solução salina, durante oito semanas. Na nona semana, um grupo tratado com DMH e um controle, foram submetidos à intervenção cirúrgica para retirada de um retalho cutâneo de 4cm no flanco direito, que cicatrizou por segunda intenção. Na 12ª semana, logo após o fechamento da ferida cutânea, os animais foram submetidos à eutanásia. O colon foi dividido em segmentos proximal e distal e examinado a nível macroscópico e histológico. Foram analisadas a incidência, distribuição e morfologia das lesões. O número total de tumores na mucosa do colon e o número de tumores por animal foi significantimente maior no grupo submetido à ferida cutânea do que no grupo tratado somente com DMH. O número de carcinomas pouco diferenciados foi significantimente maior no grupo com ferida cutânea do que em seu respectivo controle. Estes resultados sugerem que o processo de reparação de uma ferida cutânea favorece o desenvolvimento neoplásico em um órgão à distância, tal como o colon e que este efeito parece estar relacionado ao tipo histológico da neoplasia.