Histological analysis of the intestinal wall of newborn rats submitted to hypoxia and reoxygenation to evaluate the protective effect of N-Acetylcysteine

Abstract Purpose To evaluate the effect of N-Acetylcysteine (NAC) in newborn rats submitted to hypoxia and reoxygenation (H/R) conditions in an experimental model of necrotizing enterocolitis. Methods Eight pregnant rats and their 70 cubs were used (5 groups) and exposed to H/R conditions and received NAC at different times. The animals in the H/R groups were placed in a gas chamber (100% CO2) for 10 minutes and then reoxygenated for 10 minutes (100% O2), twice a day for the first three days of life, with a six-hour span between events. On the third day of life, the animals were anesthetized, laparotomized and the intestines were resected. Results The H/R and NAC groups showed changes in the intestinal wall in relation to the number, height and width of the villi when compared to the control group (p<0.0001), but with better preservation of structures in the NAC group. There were no differences between groups regarding the number (%) of mitoses. Conclusion The administration of NAC decreased the lesions in the intestinal wall of rats submitted to H/R, therefore suggesting that this drug can be used to prevent the development of necrotizing enterocolitis in newborns.

Oxidative stress assessment in intestine of newborn rats submitted to hypoxia and reoxygenation with tadalafil

Abstract Purpose: To evaluate the functional and structural response of tadalafil effects in the intestinal mucosa, using an experimental model of hypoxia and reoxygenation injury in rats. Methods: The animals were divided into 4 groups: CTL, H/R, H/R+Td and M+Td. The newborn rats allocated in groups H/R, H/R+Td and M+Td were submitted twice a day, to a gas chamber with CO2 at 100% for 10 minutes and afterward reoxygenation with O2 at 98% for 10 minutes, in the three first days of life. Tadalafil dose was given to newborn of group H/R+Td and to the pregnant rat of group M+Td. Histological analysis was made with hematoxylin-eosin technique and oxidative stress through nitrite and nitrate levels and lipid peroxidation. Results: The histological analysis showed a reduction of mucosa alterations in the groups that received tadalafil. In the oxidative stress evaluation, occurred an increase of NO levels and less lipidic peroxidation in the ileum segments that received tadalafil. Conclusion: Tadalafil provides tissue protection when administered independently to both, pregnant or newborns.

Effect of atenolol pre-treatment in heart damage in a model of intestinal ischemia-reperfusion

Abstract Purpose: To investigate the effects of atenolol in inflammatory mediator and oxidative stress in a myocardial injury by intestinal ischemia/reperfusion in rat model. Methods: Adult Wistar male rats were randomly (n=8), anesthetized and divided in: Sham: submitted to operation only; group SS+IR: intravenous saline infusion following superior mesenteric artery occlusion during 60 minutes (ischemia) and open for 120 minutes (reperfusion); group AT+IR: intravenous atenolol infusion (2 mg/kg) following superior mesenteric artery occlusion during 60 minutes (ischemia) and open for 120 minutes (reperfusion); and group AT+I+AT+R: intravenous atenolol infusion following superior mesenteric artery occlusion during 60 minutes (ischemia) and in the time 45 minutes other atenolol doses were administrated and the artery was open for 120 minutes (reperfusion), all animals were submitted to muscular relaxation for mechanical ventilation. In the end of experiment the animals were euthanized and the hearts tissue were morphology analyzed by histology and malondialdehyde by ELISA, and the plasma were analyzed for tumor necrosis factor-alpha by ELISA. Results: The group SS+IR demonstrated the higher malondialdehyde levels when compared with the atenolol treated-groups (p=0.001) in the heart tissue. The tumor necrosis factor-alpha level in plasma decrease in the treated groups when compared with SS+IR group (p=0.001). Histology analyses demonstrate pyknosis, edema, cellular vacuolization, presence of inflammatory infiltrate and band contraction in the heart tissue of the rats. Conclusion: Atenolol significantly reduce the degree of cardiac damage after intestinal ischemia-reperfusion.

Use of fibrinogen and thrombin sponge in pediatric split liver transplantation

Abstract Purpose: To analyze the use of this sponge in pediatric patients undergoing split-liver transplantation. Methods: Retrospective study, including 35 pediatric patients undergoing split-liver transplantation, divided into two groups according to the use of the sponge: 18 patients in Group A (no sponge) and 17 in Group B (with sponge). Results: The characteristics of recipients and donors were similar. We observed greater number of reoperation due to bleeding in the wound area in Group A (10 patients - 55.5%) than in Group B (3 patients - 17.6%); p = 0.035. The median volume of red blood cells transfused in Group A was significantly higher (73.4 ± 102.38 mL/kg) than that in Group B (35.1 ± 41.67 mL/kg); p = 0.048. Regarding bile leak there was no statistical difference. Conclusion: The use of the human fibrinogen and thrombin sponge, required lower volume of red blood cell transfusion and presented lower reoperation rates due to bleeding in the wound area.

Neonatal necrotizing enterocolitis rat model attenuated by a remote ischemic preconditioning in the pregnant

Abstract Purpose: To evaluate the effect of remote ischemic preconditioning (r-IPC) administered to pregnant rats, in the ileum of newborn rats subjected to hypoxia and reoxygenation. Methods: We used three pregnant rats and their newborn rats distributed in three groups: 1) Control (C) - Newborn rats born from a pregnant rat which did not undergo any intervention; 2) Hypoxia-Reoxygenation (H/R) - Newborn rats born from a pregnant rat which did not undergo any intervention, and were subjected to hypoxia-reoxygenation; 3) Remote Ischemic Preconditioning (r-IPC) - newborn rats born from a pregnant rat which was subjected to remote ischemic preconditioning twenty-four hours before giving birth and the newborn rats were subjected to hypoxia-reoxygenation. Segments of ileum were prepared for histological analysis by HE and immunohistochemistry by the Ki67 to evaluate cell proliferation, crypt depth and villus height and evaluation of apoptosis by cleaved caspase-3. Results: The intensity of the lesions was lower in the r-IPC than in the H/R group, showing significant difference (p<0.01). The r-IPC group showed a higher proliferative activity compared to the H/R group (p<0.01), with deeper crypts (r-IPC > H/R - p < 0.05), and higher villi, showing significant difference (r-IPC > H/R - (p <0.01). The occurrence of apoptosis in the H/R group was lower in comparison to groups C and r-IPC, with significant difference (H/R < r-IPC; p<0.05). Conclusion: The remote ischemic preconditioning applied to the pregnant rat protected the ileum of newborn rats subjected to hypoxia and reoxygenation, with decreased intensity of the lesions in the ileum mucosa and preservation of proliferative activity, keeping the villus height and crypt depth similar to group C.

Pediatric liver transplantation with ex-situ liver transection and the application of the human fibrinogen and thrombin sponge in the wound area / Transplante hepático pediátrico com transecção hepática ex-situ e aplicação da esponja de fibrinogênio e trombina humana na área cruenta

ABSTRACT Background: Surgical strategy to increase the number of liver transplants in the pediatric population is the ex-situ liver transection (reduction or split). However, it is associated with complications such as hemorrhage and leaks. The human fibrinogen and thrombin sponge is useful for improving hemostasis in liver surgery. Aim: Compare pediatric liver transplants with ex-situ liver transection (reduction or split) with or without the human fibrinogen and thrombin sponge. Methods: Was performed a prospective analysis of 21 patients submitted to liver transplantation with ex-situ liver transection with the application of the human fibrinogen and thrombin sponge in the wound area (group A) and retrospective analysis of 59 patients without the sponge (group B). Results: The characteristics of recipients and donors were similar. There were fewer reoperations due to bleeding in the wound area in group A (14.2%) compared to group B (41.7%, p=0.029). There was no difference in relation to the biliary leak (group A: 17.6%, group B: 5.1%, p=0.14). Conclusion: There was a lower number of reoperations due to bleeding of the wound area of ​​the hepatic graft when the human fibrinogen and thrombin sponge were used.

RESUMO Racional: Estratégia cirúrgica para aumentar o número de transplantes hepáticos na população pediátrica é a transecção hepática ex-situ (redução ou split). No entanto, ela está associada com complicações, tais como hemorragia e fístulas. A esponja de fibrinogênio e trombina humana é útil para melhorar a hemostasia nas operações hepáticas. Objetivo: Comparar transplantes hepáticos pediátricos com transecção hepática ex-situ (redução ou split) com ou sem a esponja de fibrinogênio e trombina humana. Métodos: Foi realizada análise prospectiva de 21 pacientes submetidos ao transplante de fígado com transecção hepática ex-situ com a aplicação da esponja de fibrinogênio e trombina humana na área cruenta (grupo A) e análise retrospectiva de 59 pacientes sem a esponja (grupo B). Resultados: As características dos receptores e doadores eram semelhantes. Observou-se menor número de reoperações devido à hemorragia na área da cruenta no grupo A (14,2%) em comparação com o grupo B (41,7%, p=0,029). Não houve diferença em relação à fístula biliar (grupo A: 17,6%, grupo B: 5,1%, p=0,14). Conclusão: Houve menor número de reoperações por sangramento da área cruenta do enxerto hepático quando a esponja de fibrinogênio e trombina humana foi utilizada.

Effect of folic acid in a modified experimental model of anorectal malformations adriamycin-induced in rats

PURPOSE: To determine the effect of a single dose of adriamycin (ADR) to induce anorectal malformations (ARMs) and determine the effect of folic acid (FA) in this model. METHODS: Ten female Wistar rats were divided randomly in two groups. Group A - ADR; Group B - FA+ADR. Dams from group B received daily, since two weeks before the pregnancy to the end of pregnancy, FA (50mg/kg) by gavage. Dams from both groups received ADR (6mk/kg) by intraperitoneal injection on gestational day (GD) 8. Their fetuses were harvested by cesarean section on GD21 and were examined looking for ARMs. The thickness of anal stratified squamous epithelium (ASSE) and intestinal epithelium (IE) were analyzed. p≤0.05*. RESULTS: 81 fetuses were harvested. The number of fetuses; number of ARMs; mean (∆%) (± SD) were determined to be, respectively: ADR - 41[29;65%(±37%)] versus FA+ADR - 40[04;16%(±36%)] (p=0.05). AMRs were significantly lower in FA+ADR group than in ADR group (p=0.05). The thickness (µm) of ASSE (± SD) and IE (± SD) were measured, respectively: ADR - [25.98(±0.74) and 19.48(±1.68)] versus FA+ADR - [24.74(±0.91) and 24.80(±0.81)] (p<0.005). The thickness of IE was significantly enlarged when FA was given (p<0.005). CONCLUSIONS: Single dose of adriamycin on D8 was able to induce anorectal malformations. Folic acid reduces the number and enlarged the IE of ARMs ADR-induced.

Is it possible folic acid reduce anorectal malformations ethylenethiourea induced in rats?

PURPOSE: To investigate the effect of folic acid (FA) in an experimental model of anorectal malformations (ARMs) ethylenethiourea (ETU) induced.METHODS:Eight female Wistar rats were divided randomly in two groups. Group A - ETU; Group B - FA+ETU; Dams from group B received daily, since two weeks before pregnancy to the end of pregnancy, FA (50mg/kg) by gavage. Dams from groups A and B, received 1% ETU (125mk/kg) by gavage on gestational day (GD) 11. Their fetuses were harvested by cesarean section on GD21 and were examined looking for ARMs. The thickness of anal stratified squamous epithelium (ASSE) and intestinal epithelium (IE) were analyzed. p<0.05*.RESULTS:One hundred and one embryos were harvested. The number of embryos; number of ARMs; mean statistical % (± SD) were determined to be, respectively: ETU - 49 [30;65% (±24%)] versus FA+ETU - 52 [1;02% (±3%)] (p=0.025). AMRs were significantly lower in FA+ETU group than in ETU group (p=0.025). The thickness (µm) of ASSE (± SD) and IE (± SD) were measured, respectively: ETU - [27.75 (±0.56) and 18.88 (±0.93)] versus FA+ETU - [28.88 (±0.61) and 21.11 (±0.16)] (p=0.001). The thickness of IE was significantly enlarged when FA was given (p=0.001).CONCLUSION:Folic acid reduces the number and enlarged the IE of ARMs ETU-induced.

Effects of maternal ischemic preconditioning in the colon of newborn rats submitted to hypoxia-reoxygenation insult

PURPOSE: To evaluate the effects of maternal remote ischemic preconditioning (IPCr) in the colonic mucosa of newborn rats subjected to hypoxia and reoxygenation. METHODS: Newborn Wistar rats were divided into three groups. Control Group (CG), Hypoxia and Reoxygenation Group (HRG) and Remote Ischemic Preconditioning Group (IPCrG). Hypoxia and reoxygenation was performed 2x per day, with an interval of 6 hours, on the 1st, 2nd and 3rd days of life, with 10 minutes of CO2 at 100%, followed by 10 minutes O2 at 100%(HRG/IPCrG). The maternal IPCr was performed 24 hours before delivery by applying a rubber band tourniquet to the left hind limb (IPCrG). Segments of the colon underwent histological (HE) and immunohistochemical analysis for caspase-3 and COX - 2. RESULTS: The histological findings showed no intestinal mucosal damage in the CG group and severe lesions in HRG that was attenuated in the IPCrG (p<0.05). The expression of the apoptotic cells was lower in the HRG group than in the CG and IPCrG. The COX-2 expression was intense in HRG and attenuated in the IPCrG (p<0.05). CONCLUSIONS: Maternal IPCr protected the colonic mucosa of newborn rats subjected to hypoxia and reoxygenation, reducing the morphological alterations and inflammatory response. It ameliorates the occurrence of apoptosis, keeping the physiological process of renewal and regeneration in the epithelial lining of the colonic mucosa. .

The effect of simvastatin on the regeneration of surgical cavities in the femurs of rabbits

To evaluate the effect of a local application of simvastatin gel in repairing bone defects in the femurs of rabbits. METHODS: Two standard surgical cavities were created in the femoral epiphysis of 18 rabbits. In the simvastatin group (SG), the cavities were filled with a collagen sponge soaked in 0.5 ml of a simvastatin (1 mg) gel, and the cavities were covered with a biological membrane. The bone cavities in the second group (control group) were filled with a blood clot and covered with a biological membrane. On the 7th, 21st and 42nd days, six animals in each group were euthanized, and the femurs were subject to histological evaluation (vascularity, fibrosis, reactive bone formation, osteoblasts, and osteoclasts) and immunohistochemical (anti-VEGF and anti-osteocalcin) analysis. The results were analyzed using a Wilcoxon test (p<0.05). RESULTS: There were significant differences between the two groups: the SG had greater scores in comparison with the CG in terms of the degree of vascularity on the 7th and the 21st days, fibrosis on the 21st day, bone formation reaction on the 21st and the 42nd days and the number of osteoblasts and osteoclasts on the 42nd day. The immunohistochemical expression was also greater for osteocalcin and VEGF on the 7th, 21st and 42nd days. CONCLUSION: Surgical defects created in rabbit femurs were treated locally with simvastatin gel to stimulate bone repair, which promoted an ameliorative effect in the morphological and immunohistochemical markers of bone regeneration.

Hepatic damage in newborns from female rats exposed to the pesticide derivative ethylenethiourea / Lesões hepáticas em recém-nascidos de ratas expostas ao derivado de agrotóxico etilenotioureia

PURPOSE: To evaluate hepatic morphological-histological abnormalities in newborns from female rats exposed to ethylenethiourea. METHODS: A randomized study was conducted on fifty-five newborn Wistar rats were studied: 34 in the experimental group, whose mothers had been exposed to 1% ethylenethiourea; and 21 in the control group, whose mothers had received 0.9% physiological solution. The solution was administered via gavage on the 11th day of gestation. Cesarean section was performed on the 20th day of gestation. The newborns' livers were examined and any morphological-histological abnormalities were registered. The presence of megakaryocytes was quantified in 50 microscope fields, as the total number of these cells per mm². RESULTS: The entire experimental group presented abnormalities of embryonic formation, with musculoskeletal anomalies, digestive system anomalies, hepatic congestion and friability, hydrops and delayed intrauterine growth. The histopathological analysis showed that morphological-histological hepatic destructuring had occurred in all entire experimental with removal of the hepatic trabeculae and severe hepatic megakaryocytosis. The mean megakaryocyte density ranged from 107.9 to 114.2 per mm², and it was eight times greater than in the control group, thus characterizing a situation of extramedullary hematopoiesis. CONCLUSION: The fetal exposure to ethylenethiourea caused hepatic damage characterized by severe extramedullary hematopoiesis.

OBJETIVO: Avaliar alterações hepáticas morfohistológicas em recém-nascidos de ratas prenhes expostas à etilenotioureia. MÉTODOS: Realizado ensaio randomizado em animais de experimentação, onde foram estudados 55 recém-nascidos de ratas Wistar, 34 do Grupo Experimento, expostas a etilenotioureia 1% e 21 do Grupo Controle, em que a rata prenhe recebeu solução fisiológica 0,9%, ambos por gavagem no 11º dia de gestação. Realizada no 20º dia de gestação cesariana, analisados os fígados dos recém-nascidos e registradas as alterações morfohistológicas. Realizou-se a quantificação dos megacariócitos em 50 campos microscópicos, avaliando a quantidade total destas células por mm². RESULTADOS: Todos os recém-nascidos do Grupo Experimento apresentaram alterações na formação embrionária, com anomalias musculoesqueléticas, anormalidades do sistema digestório, congestão e friabilidade hepática, hidropisia e crescimento intrauterino retardado. A análise histopatológica mostrou desestruturação hepática morfohistológica em todos os recém-nascidos expostos à etilenotioureia, com destrabeculação dos hepatócitos e intensa megacariocitose hepática, apresentando média da densidade de megacariócitos de 107,9 até 114,2 por mm² sendo cerca de oito vezes maior que no Grupo Controle, caracterizando hematopoese extramedular. CONCLUSÃO: A exposição fetal a etilenotioureia provocou danos hepáticos caracterizados pela intensa hematopoese extramedular.

Abnormalities of digestive tract innervation in rat fetus treated with ethylenethiourea / Anomalias da inervação do trato digestório de fetos de ratas expostas à etilenotioureia

PURPOSE: The pathophysiology of abnormalities associated with myenteric plexus lesions remains imperfectly understood. Such abnormalities have been correlated with subocclusive intestinal conditions in children with Hirschsprung's disease, cases of chronic constipation and, postoperatively, in cases of anorectal anomalies. This study evaluated abnormalities of the myenteric plexus in fetus from female rats that received ethylenethiourea. METHODS: Female rats were exposed to ethylenethiourea on the 11th day of pregnancy (experimental group) or to 0.9 percent physiological solution (control group). Abnormalities were only found in the experimental group. The digestive tract muscle layer was analyzed morphometrically and changes to the frequencies of nerve plexus cells and interstitial cells of Cajal were evaluated, using hematoxylin-eosin, S-100 protein, neuron-specific enolase and C-Kit, respectively. RESULTS: Muscle and skeletal abnormalities were observed in 100 percent, anorectal anomalies in 86 percent, absent tail in 71 percent, short tail in 29 percent, duodenal atresia in 5 percent, esophageal atresia in 5 percent and persistent omphalomesenteric duct in 5 percent. Histopathological analysis showed a thinner muscle layer associated with lower frequencies of ganglion cells and interstitial cells of Cajal, in all gastrointestinal tract. CONCLUSION: Severe nerve plexus abnormalities associated with muscle layer atrophy were observed throughout the gastrointestinal tract in newborn rats exposed to ethylenethiourea.

OBJETIVO: As anomalias associadas a lesões dos plexos mioentéricos permanecem sem plena compreensão da sua fisiopatologia. Alterações nos plexos nervosos têm sido correlacionadas com quadros suboclusivos intestinais em crianças portadoras de doença de Hirschsprung, em constipação crônica e no pós-operatório de anomalias anorretais. Este estudo avaliou as anomalias do plexo mioentérico em fetos de ratos fêmea que ingeriram etilenotioureia (ETU). MÉTODOS: Ratos fêmea foram expostos no 11º dia de gestação a ETU 1 por cento no Grupo Experimento e a solução fisiológica 0,9 por cento no Grupo Controle. Foram observadas anomalias apenas no Grupo experimento, sendo realizada morfometria da camada muscular e avaliadas alterações da frequência celular nos gânglios do plexo mioentérico e nas células intersticiais de Cajal (CIC) utilizando hematoxilina-eosina, P S-100, Enolase Neurônio Específica e C-KIT. RESULTADOS: Foram observadas anomalias musculoesqueléticas (100 por cento), anorretais (86 por cento), ausência de cauda (71 por cento), cauda curta (29 por cento), atresia duodenal (5 por cento), atresia esofágica (5 por cento) e conduto onfalomesentérico persistente (5 por cento). A análise histopatológica mostrou adelgaçamento da camada muscular associada às alterações da frequência das células ganglionares e das CIC em todos os segmentos do trato gastrointestinal. CONCLUSÃO: Foram observadas alterações graves nos plexos nervosos associadas ao adelgaçamento da camada muscular de todo o trato gastrointestinal nos fetos expostos a ETU.

Defeitos congênitos e exposição a agrotóxicos no Vale do São Francisco / Congenital defects and exposure to pesticides in São Francisco Valley

OBJETIVO: avaliar a associação entre a exposição dos genitores aos agrotóxicos e nascimentos com defeitos congênitos no Vale do São Francisco, bem como o perfil sociodemográfico e os defeitos encontrados. MÉTODOS: estudo tipo caso-controle, sendo que para cada caso (recém-nascido com defeito congênito), eram dois controles (recém-nascidos saudáveis) nascidos na cidade de Petrolina, no Vale do São Francisco, em 2009. A amostra constou de 42 casos e 84 controles. Os dados formam colhidos com uso de questionário estruturado, adaptado do Estudo Colaborativo Latino-Americano de Malformações Congênitas (ECLAMC), acrescido de questões relacionadas à exposição aos agrotóxicos, análise do prontuário e contato com a pediatra do hospital. Foi realizado o teste do χ2 com nível de significância de 5 por cento para identificar as variáveis com maiores diferenças entre os grupos caso e controle. Em seguida, foi calculado o Odds Ratio (OR) amostral, bem como o OR obtido por análise de regressão logística e, finalmente, realizou-se uma análise de regressão logística multivariada. RESULTADOS: houve maior exposição aos agrotóxicos durante a gestação em neonatos com defeitos congênitos se comparados aos saudáveis. Maior risco foi observado quando pelo menos um dos genitores foi exposto aos agrotóxicos (OR ajustado = 1,3; IC95 por cento = 0,4-3,9). As variáveis sociodemográficas associadas aos defeitos congênitos foram: baixa escolaridade, baixo peso, prematuridade, genitores jovens, doenças crônicas e fatores físicos. Foram encontrados com maior frequência os polimalformados e os defeitos dos sistemas musculoesquelético e nervoso. CONCLUSÃO: o presente estudo, a despeito de não apresentar significância, sugere associação entre a exposição aos agrotóxicos e a ocorrência de defeitos congênitos.

PURPOSE: to evaluate associations between parental exposure to pesticides and births with congenital defects in São Francisco Valley, as well as the demographic profile and the defects found. METHODS: in this case-control study, each case (newborns with congenital defects) had two controls (healthy newborns). The subjects were born in the city of Petrolina, in São Francisco Valley, in 2009. The sample consisted of 42 cases and 84 controls. Data were gathered by a structured questionnaire adapted from Latin-American Collaborative Study of Congenital Malformations (ECLAMC), with the addition of questions related to exposure to pesticides, analysis of the medical records and contact with the hospital's pediatrician. The χ2 test was performed with a significance level of 5 percent to identify the variables with the greatest differences between case and control groups. Odds Ratio (OR) for the sample was calculated, as well as the OR obtained by logistic regression analysis, and finally, multivariate logistic regression analysis was performed. RESULTS: there was a greater exposure to pesticides during pregnancy in infants with congenital defects compared to healthy subjects. Increased risk was observed when at least one parent was exposed to pesticides (adjusted OR = 1.3; 95 percentCI = 0.4 - 3.9). The sociodemographic variables associated with congenital defects were: low school level, low weight, prematurity, young parents, chronic diseases, and physical factors. Multiple malformations and defects of the musculoskeletal and nervous systems were more frequently found. CONCLUSIONS: the present study suggests an association between exposure to pesticides and the occurrence of congenital defects, although the data were not significant.

Ausência de mutações no proto-oncogene RET relacionadas com carcinoma medular de tireoide em pacientes com doença de Hirschsprung / Absence of RET proto-oncogene mutations related with medullary thyroid carcinoma in patients with Hirschsprung disease

Objetivo: O objetivo desse estudo é avaliar, em pacientes com Doença de Hirschsprung, a incidência e o tipo de mutações no proto-oncogene RET encontradas. Método: Foram estudados 15 pacientes com diagnóstico de Doença de Hirschsprung. As características fenotípicas foram obtidas através de entrevista com os pacientes e familiares e através de revisão de prontuário. As características genotípicas foram obtidas como se segue: dos leucócitos do sangue periférico foi extraído o DNA genômico. Amplificamos os exons 10, 13 e 16 através da Reação de Polimerase em Cadeia (PCR). O produto PCR foi purificado e submetido à sequenciamento direto, e os resultados do sequenciamento foram analisados utilizando sequências previamente depositadas no GeneBank. Resultados: Os pacientes apresentaram a distribuição por sexo de 13 do sexo masculino (86,7%) e 2 do sexo feminino (13,3%).A idade atual variou de 2 a 16 anos, com a média de 7 anos. Nenhum dos pacientes apresentou características fenotípicas de Neoplasia Endócrina Múltipla tipo 2A, 2B ou Carcinoma Medular de Tireoide Familiar, ou havia antecedente familiar positivo para essas doenças. Quanto às características genotípicas: o produto do sequenciamento genético, não apresentou alterações nos exons 10 e 16 em nenhum paciente, mas foi encontrado um polimorfismo em heterozigose no exon 13 no códon 769 em 4 pacientes. Conclusões: não foram encontradas mutações no proto-oncogene RET concomitantes à Neoplasia Endócrina Múltipla tipo 2A, 2B ou Carcinoma Medular de Tireoide Familiar, nos pacientes com Doença de Hirschsprung estudados, sendo encontrado polimorfismo no códon 769 em 4 pacientes.

Objective: To assess the frequency of mutations of the RET proto-oncogene in patients with Hirschsprung´s Disease and its association with Multiple Endocrine Neoplasia type 2. Method: 15 patients with Hirschsprung´s Disease were evaluated, regarding the phenotypic and genotypic characteristics. The phenotypic characteristics were obtained by interview and patients´ charts evaluation. Genotypic characteristics evaluation: genomic DNA was extracted from peripheral blood lymphocytes. Primers specific for exons 10, 13 e 16 of the RET gene were designed and used to generate Polimerase Chain Reaction products, which were purified and directly sequenced. The 3 exons were sequenced in both directions - sense and antisense - and the results analyzed using the sequences deposited on GeneBank. Results: Thirteen (86.7%) patients were male and 2 (13.3%) female. The age mean age was 7 years old, ranging from 2 to 16 years old. No patient presented phenotypic characteristics of Multiple Endocrine Neoplasia type 2, or familial history. Regarding the genotypic characteristics, no patient presented mutations on exons 10 or 16, but 4 patients presented a heterozigotic polymorphism on exon 13, codon 769. Conclusion: there was no concomitant mutation on the RET proto-oncogene, of Multiple Endocrine Neoplasia type 2 and Hirschsprung´s Disease in the patients studied.

Clinical, manometric and profilometric evaluation after surgery for Hirschsprung's disease: comparison between the modified Duhamel and the transanal rectosigmoidectomy techniques / Avaliação clínica, manométrica e profilométrica após correção cirúrgica para doença de Hirschsprung: comparação entre as técnicas de Duhamel modificado e a retossigmoidectomia transanal modificada

PURPOSE: To evaluate fecal continence, anorectal manometry (AM) and profilometry (P), in patients operated for congenital megacolon, using either the modified Duhamel technique (MDT) or the modified transanal rectosigmoidectomy (MTR) technique. METHODS: 42 patients were evaluated clinically and via AM and P, for postoperative control. The resting, coughing, voluntary contraction, maintained voluntary contraction and perianal stimulation pressures were investigated. The rectosphincteric reflex was tested and the simple and enhanced pressure curves were evaluated. The three-dimensional profilometric outline was produced. Student's t, chi-squared and Fisher's exact tests were used for statistical analysis (p<0.05). RESULTS: AM showed mean resting pressures of 53.44 mmHg for MDT and 60.67 mmHg for MTR, and mean voluntary contraction pressures of 94.50 mmHg for MDT and 95.47 mmHg for MTR. There was no statistical difference between the groups. The shapes of the simple and enhanced pressure curves did not present any statistical difference, independent of the surgical technique used. CONCLUSION: The two surgical techniques were equivalent. MDT caused greater incidence of postoperative constipation that MTR did. AM and P were shown to be excellent tests for postoperative follow-up among these patients.

OBJETIVO: Avaliar a continência fecal, a manometria anorretal (MAR) e a profilometria (PFM), em pacientes submetidos a tratamento cirúrgico do megacolo congênito pelas técnicas de Duhamel modificado (DM) ou de retossigmoidectomia transanal modificada (RTM). MÉTODOS: 42 pacientes foram clinicamente avaliados e submetidos à MAR e PFM para controle pós-operatório. Foram pesquisadas as pressões no repouso (PR), à tosse (T), à contração voluntária (CV), à contração voluntária mantida (CVM) e à estimulação perianal (EPA). O reflexo reto-esficteriano (RRE) foi testado e as curvas pressóricas simples e potencializada foram avaliadas. Foi elaborado traçado tridimensional de PFM. Utilizamos os testes t de Student, Qui-Quadrado e exato de Fisher para análise estatística (p<0,05). RESULTADOS: A MAR mostrou médias de PR=53,44 mmHg para DM e 60,67 mmHg para RTM; CV média = 94,50 mmHg para o grupo DM e 95,47 mmHg para o grupo RTM. Não houve diferença estatística entre os grupos. A forma das CPS e CPP não apresentou diferença estatística, independentemente da técnica cirúrgica utilizada CONCLUSÃO: As duas técnicas operatórias foram manometricamente equivalentes. DM determinou maior incidência de constipação pós-operatória que RTM. A MAR e a PFM revelaram-se excelentes exames para acompanhamento destes pacientes após a cirurgia.

Rugosidade superficial de compósitos microparticulados e nanoparticulados após acabamento e polimento / Surface roughness of microparticulated and nanoparticulated composites after finishing and polishing procedures

Objetivo: Avaliar a rugosidade superficial de resinas compostas microparticulada (Durafill, Heraeus Kulzer Weihrheim, Germany), nanoparticuladas 4 Seasons (Ivoclar Vivadent, Schaan, Liechtenstein), Esthet X (Dentsply, Milford, DE, USA) Point 4 (Kerr CO, Orange, CA, USA),Filtek-Supreme (3M-ESPE, Dental Products, St. Paul, MN, USA). Métodos: Após o acabamento com pontas diamantadas F (KG Sorensen, Barueri, Brasil) e polimento com pontas de silicone Politipit (IvoclarVivadent, Schaan, Liechtenstein) nas cores cinza, verde e rosa, foram realizadas quatro etapas de finalização, uma de acabamento e três de polimento, simulando o acabamento e polimento de uma restauração de resina fotopolimerizável. Dez espécimens de cada resina composta foram mensurados quanto aos valores de rugosidade superficial com rugosímetro (Mitutoyo Corporation, Tokyo, Japan) após cada etapa de acabamento e polimento. Resultados: Os resultados demonstraram que as resinas nanoparticuladas e microparticuladas apresentaram diferenças significantes quanto aos valores de rugosidade superficial em todos os estágios de acabamento e polimento. Conclusão: Entre as resinas nanoparticuladas, a 4 Seasons (Ivoclar Vivadent, Schaan, Liechtenstein) e a Point 4 (Kerr CO, Orange, CA, USA), assim como a resina microparticulada Durafill (Heraeus Kulzer Weihrheim, Germany), apresentaram baixos valores de rugosidade superficial após esgotarem-se todas as etapas de acabamento e polimento.

Objective: To evaluated the surface roughness of one microparticulate resin composite Durafill (Heraeus Kulzer Weihrheim, Germany) and four nanoparticulate resins 4 Seasons (Ivoclar Vivadent, Schaan, Liechtenstein) Esthet x (Dentsply, Milford, DE, USA), Point 4 and Supreme(3M-ESPE, Dental Products, St. Paul, MN, USA). Methods: After finishing with a diamond bur point (F), and polishing with silicone points of gray, green and pink color Politipit (Ivoclar Vivadent, Schaan, Liechtenstein), four stages of completion were performed, simulating one of finishing and three of polishing a resin restoration. Ten samples of each composite resin were measured for surface roughness with surface profilometer (Mitutoyo Corporation, Tokyo, Japan) after each of finishing and polishing sequence.Results: The results showed that nanoparticulate and microparticulate resins presented a significant difference in the surface roughness values, in all finishing and polishing steps. Conclusion: Of the nanoparticulate resins 4 Seasons (Ivoclar Vivadent, Schaan, Liechtenstein), Point 4 (Kerr CO, Orange, CA, USA), and also microparticulate Durafill (Heraeus Kulzer Weihrheim, Germany) presented significantly lower surface roughness values after completing all the finishing and polishing stages.

Comparison between perfusion and balloon techniques for performing anorectal manometry in children with intestinal constipation / Comparação das técnicas de balão e de perfusão para a realização de manometria anorretal em crianças portadoras de constipação intestinal

INTRODUCTION: Two anorectal manometry techniques have commonly been utilized: the perfusion technique and the balloon technique. PURPOSE: To compare both techniques in children with intestinal constipation who had not undergone surgical treatment for its correction. METHODS: Thirty-nine children aged between four and fourteen years underwent anorectal manometry using both techniques at random. Resting pressure, pressure response to voluntary contraction, coughing and perianal stimulation, maximum pressure on the anal canal pressure curve, and presence of rectosphincteric reflex were registered and submitted to statistics. Vectorgraphy of the sphincter muscle complex was obtained by perfusion technique. RESULTS: The statistical comparison between the techniques revealed statistically significant differences in resting pressure (p=0.041), pressure response to voluntary contraction (p=0.026) and maximum pressure within the pressure curve (p=0.010). The rectosphincteric reflex was demonstrated in 21 patients by both techniques. CONCLUSIONS: The perfusion technique presented greater sensitivity in the following parameters: resting pressure, pressure response to voluntary contraction and maximum pressure within the pressure curve. The methods studied are equivalent regarding the measurement of pressure responses to coughing and perianal stimulation and the investigation of rectosphincteric reflex.

INTRODUÇÃO: A manometria anorretal tem sido aceita como uma técnica objetiva de estudar a função do complexo muscular esfincteriano. Duas técnicas para o mesmo exame têm sido utilizadas: por perfusão e por balão. OBJETIVO: Comparar as técnicas entre as crianças portadoras de constipação intestinal que não foram submetidas a tratamento cirúrgico como forma de tratamento. MÉTODOS: Trinta e nove crianças com idades entre quarto e quatorze anos foram submetidas à Manometria anorretal utilizando-se ambas as técnicas de forma randomizada. Analizou-se a pressão de repouso, a pressão de contração voluntária, a pressão de contração reflexa, a pressão máxima de contração, o reflexo reto-esfincteriano. Além desses parâmetros, o vetorgrama do canal anal foi estudado pela técnica de perfusão. A análise estatística foi feita por meio de Wilcoxon signed rank test. RESULTADOS: A comparação estatística entre as técnicas revelou diferenças significantemente estatísticas nos parâmetros: pressão de repouso (p= 0.041), Pressão de contração voluntária (p= 0.026) e pressão máxima de contração (p= 0.010). Não houve diferença estatisticamente significante nos parâmetros: pressão de contração reflexa por tosse (p= 0.141) ou por estimulação perianal (p= 0.117). O reflexo reto-esfincteriano foi demonstrado em 21 pacientes em ambas as técnicas. CONCLUSÕES: A técnica de perfusão tem maior sensibilidade para os seguintes parâmetros: pressão de repouso, pressão de contração voluntária e pressão máxima de contração. As técnicas se equivalem no que diz respeito à pressão de contração reflexa e reflexo reto-esfincteriano.

Evaluation of porous vitreous carbon or silicon implants by radiology in rat's skull / Avaliação radiológica de implantes de carbono vítreo poroso ou silicone em crânio de ratos

PURPOSE: Evaluate by CT the use of porous vitreous carbon (PVC) and silicon (S) implants as the replacement bone in the craniofacial skeleton of rats. METHODS: 40 rats divided in: Group A (n=20) PVC submitted to the implant of a fragment in skull. After the euthanasia, the animals were divided into two subgroups: A I: 10 animals, studied in the 7th postoperative day (P.O) and AII: 10 animals, studied in the 28th P.O. In group B, S, 20 rats were submitted to S implant in the skull. All other steps were identical to group A, with designation of subgroups BI and BII. CT with beams in axial cuts of 1 mm thickness to obtain 3-D information It was used Hounsfield scale for evaluate the radio density of the implant. They were used non parametric tests to analyze the results. RESULTS: The 7th PO boss remained in the two groups, but for 28th PO, observed reduction in the volume of the implant in Group A, not observed in group B. CT studies noticed different radio densities around all of S prostheses (pseudo-capsule), that don't appeared in CPV implants. The S has remained unchanged in the CT, but the CPV has had a modification in its radio density (p<0,05), in all implants. CONCLUSION: In CT evaluation the implants of CPV have greater deformation that the S, which makes them not suitable for replacement of membranous bone in the rat skull.

OBJETIVO: Realizar avaliação através de tomografia computadorizada (TC) de implantes de carbono vítreo poroso (CVP) e silicone (S) para sua utilização na substituição óssea no esqueleto craniofacial de ratos. MÉTODOS: Foram utilizados 40 ratos Wistar divididos em: Grupo A (n=20), implantes subperiostais de CVP no crânio. Após o momento da eutanásia os animais foram divididos em dois subgrupos: A I: 10 animais, estudados no 7(0) dia pós-operatório (PO) e AII: 10 animais, estudados no 28(0) PO. No grupo B (n=20), os ratos foram submetidos ao implante de silicone no crânio. Todas outras etapas foram idênticas ao grupo A, com a designação de subgrupos BI e BII. Foi realizada tomografia computadorizada com cortes axiais de 1 mm de espessura para obtenção de imagens tridimensionais. A escala de Hounsfield foi utilizada para avaliação da radiodensidade dos implantes. Testes estatísticos não paramétricos foram utilizados para analisar os resultados. RESULTADOS: O volume do implante foi mantido ao 7(0) PO nos dois grupos, mas ao 28(0) PO, ocorreu uma redução no volume do implante no grupo A, não observada no grupo B. Os estudos tomográficos demonstraram a presença de uma pseudo-cápsula ao redor dos implantes no grupo B, não observada nos implantes de CVP. Os implantes de silicone permaneceram inalterados na TC, mas os de CVP apresentaram modificação na sua radiodensidade e deformação (p<0,05). CONCLUSÃO: Na avaliação, através de TC, os implantes de CPV apresentam maior deformação que os de S, o que os torna inadequados para substituição do osso membranoso no crânio de ratos.

Study of the density of ganglion cells in the terminal bowel of rats with anorectal malformations

PURPOSE: To study the ganglion cells (GC) in the terminal bowel of rats with ethylenethiourea (ETU) induced anorectal malformations (ARM). METHODS: The animals were divided into three groups: Group A - normal fetuses from pregnant rats that were not administered ETU; Group B - fetuses without ARM born from pregnant rats that were administered ETU and Group C - fetuses with ARM born from pregnant rats that received ETU. ETU was administered on the 11th day of pregnancy at the dose of 125 mg/kg body weight by gastric gavage. The rats had cesarean section on the 21st day of gestation. The fetuses’ terminal bowel tissue was analyzed by immunohistochemistry to demonstrate ganglion cells. RESULTS: Statistically significant differences were found between groups A, B and C regarding ganglion cell densities. Group A had the highest cell density, followed by Group B and the lowest density was found in Group C. CONCLUSION: Ganglion cell densities are decreased in the terminal bowel of rats with ARM.

OBJETIVO: Estudar as células ganglionares (CG) no intestino terminal de ratos portadores de anomalia anorretal (AAR) induzida pela etilenotiouréia (ETU). MÉTODOS: Os animais foram distribuídos em três grupos: Grupo A - fetos normais, obtidos de ratas grávidas às quais não foi administrada ETU; Grupo B - fetos não portadores de AAR obtidos de ratas grávidas às quais foi administrada ETU e Grupo C - fetos portadores de AAR obtidos de ratas grávidas às quais foi administrada ETU. A ETU foi administrada no décimo primeiro dia de gestação na dose de 125 mg/Kg, por gavagem. As ratas foram submetidas à laparotomia e histerotomia para retirada dos fetos no vigésimo primeiro dia de gestação. O intestino terminal dos fetos foi retirado e analisado por imunohistoquímica para pesquisa de CG. RESULTADOS: Foram encontradas diferenças estatisticamente significantes entre os grupos A, B e C quanto à densidade de CG. O grupo A apresentou a maior densidade, seguida pelo grupo B, e a menor densidade foi encontrada no Grupo C. CONCLUSÃO: Existe uma menor densidade de CG no intestino terminal de ratos portadores de AAR.