José Luiz Martins

Nitric Oxide Levels in the Intestines of Mice Submitted to Ischemia and Reperfusion: l-Arginine Effects

OBJECTIVE Usually an experimental necrotizing enterocolitis experimental model, we Investigated nitric oxide levels in intestinal tissues of newborn mice with or without l-arginine therapy during sessions of ischemia and reoxygenation. METHODS Twenty-six newborn mice from the Wistar EPM-1 lineage, weighing from 4.5 to 6.2 g, were randomly assigned to three groups: G-I/R, hypoxia and reoxygenation; G-Arg, l-arginine treatment I/R; and G-CTL, controls. G-I/R and G-Arg mice underwent twice a day during their first 3 days of life exposure to gas chambers with 100% CO(2) for 5 minutes at 22 degrees C before reoxygenation with 100% O(2) for another 5 minutes. After 12 hours, all animals were sedated, laparotomized, and had samples of ileum and colon taken and- either formalin fixed histopathologic examinations or frozen to -80 degrees C for estimation of tissue nitric oxide levels. Intestinal injuries were classified according to the criteria of Chiu et al. RESULTS The G-I/R and G-Arg groups showed injuries characteristic of necrotizing enterocolitis (NEC) with an improved structural preservation rate in G-Arg. The concentration of nitric oxide in the Ileum was much higher with G-Arg (16.5 +/- 4.9; P = 0.0019) G-I/R (7.3 +/- 2.0). This effect was not observed in the colon: G-I/R = 10.7 +/- 4.6 versus G-Arg = 15.5 +/- 8.7 (P = .2480). CONCLUSION Supply of L-arginine increased tissue levels of nitricoxide and reduced morphologic intestinal injury among mice undergoing I/R.

Neonatal acute appendicitis: a strangulated appendix in an incarcerated inguinal hernia.

Abstract. A 4-day-old infant with acute appendicitis (AA) due to incarceration of a right inguinal hernia is presented. Although appendicitis is the most common condition requiring abdominal surgery, the reported occurrence of AA subsequent to neonatal hernia incarceration is exceptionally rare.

Sacral ratio and fecal continence in children with anorectal malformations

To evaluate the sacral ratio (SR) in patients with an anorectal malformation (ARM) and verify whether it has predictive value for fecal continence.

Defeitos congênitos e exposição a agrotóxicos no Vale do São Francisco

PURPOSE: to evaluate associations between parental exposure to pesticides and births with congenital defects in Sao 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 Sao 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 hospitals pediatrician. The χ2 test was performed with a significance level of 5% 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%CI = 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.

Glycine reduces tissue lipid peroxidation in hypoxia-reoxygenation-induced necrotizing enterocolitis in rats

PURPOSE To assess the protective effect of glycine in an experimental model of Neonatal Necrotizing Enterocolitis (NEC). METHODS Fifty (50) neonatal Wistar rats, from a litter of six female rats and weighing 4 to 6 grams, were used. Five animals were cannibalized and the 45 remaining were distributed into three groups: the G1 normal control group (n=12); the G2 Group (n=16), of animals that underwent hypoxia-reoxygenation (HR); the G3 Group of animals (n=17) that underwent HR following a 5% intraperitoneal glycine infusion. The animals underwent hypoxia in a CO2 chamber receiving an air flow of 100% CO2 for 5 minutes and reoxygenation receiving an O2 flow at 100% for 5 minutes. One centimeter long small bowel and colon segments were prepared for histological analysis. The rest of the bowel was removed in a block and frozen at minus 80 degrees C for homogenization and determination of tissue malondialdehyde (MDA). Tissue lesions were classified as Grade 0 to Grade 5, according to the level of damaged mucosa. RESULTS The animals in Group G1 had levels of small bowel and colon lesion significantly smaller as compared to the animals in Groups G2 and G3. The G2 group had mean MDA values significantly higher than the animals in the G1 (p = .015) and G3 (p=0.021) groups. MDA values did not differ significantly (p = 0.992) for the animals in groups G1 and G3. CONCLUSION Glycine reduces tissue MDA levels (a measurement of lipid peroxidation) following HR in neonatal rats.

Modified Transanal Rectosigmoidectomy for Hirschsprung's Disease: Clinical and Manometric Results in the Initial 20 Cases

PURPOSE The authors describe a modified technique of primary transanal rectosigmoidectomy for Hirschsprungs disease (HD), using a Swenson like procedure to perform the anastomosis between the colon and the rectum, and the preliminary results from this in children. METHODS Twenty children, of whom, 90% were boys and 10% girls, 50% white and 50% nonwhite, aged 15 days to 10 years and with HD proven via biopsy, underwent a transanal pull-through procedure over a 29-month period. Postoperative follow-up ranged from 29 to 5 months. The proximal cut edge of the mucosal and submucosal cuff was tagged with multiple polypropylene 4-0 sutures, which were used for traction of the intestinal layers outside. The rectal mucosa was incised circumferentially using cautery, to perform rectal dissection approximately 1.5 cm from the dentate line, except in newborn case, in which the proximal cut edge was 0.5 cm from the dentate line. The dissection extended in an upward direction around the entire rectal circumference as far as the opening of the peritoneal reflection. The full thickness of rectum and sigmoid were mobilized outside through the anus, with division and coagulation of the rectal and sigmoid vessels using cautery or ligatures with cotton 4-0. The dissected colon then was divided above the transition zone, which was confirmed via full-thickness biopsy sections and with frozen section confirmation of ganglion cell presence. The authors performed a modified Swenson anastomosis technique, using a seromuscular polyglactin 4-0 separate-stitch suture. No drains were used. RESULTS Normal bowel movements were displayed by all patients at the follow-up. All patients underwent a defecogram and anorectal computerized manometry at 3 months after surgery that showed an absence of stenosis and good anorectal sphincter muscle complex function. The incidence of complications in our series was 10%. CONCLUSIONS During the follow-up period of 29 months, all patients had normal bowel movements and normal anorectal manometric pressure profiles.

Posterior urethral injuries and the Mitrofanoff principle in children

To report our experience of children with trauma causing posterior urethral injury who at some stage underwent a Mitrofanoff intervention, as post‐traumatic urethral injuries can demand long‐term treatment which (regardless of the surgical intervention) requires a period of dilatation of the reconstructed urethra.

Do lesions of the enteric nervous system occur following intestinal ischemia/reperfusion?

PURPOSE To evaluate tissue lesions, especially those of the intestinal innervation, in an excluded jejunal loop subjected to ischemia and reperfusion in rats. METHODS To evaluate the role of ischemia and reperfusion lesions in an excluded intestinal loop, four groups of 20 rats were set up: control group (GCEI7) and three experimental groups (GIREI7, GIREI14 and GIREI28). They were all subjected to exclusion of an intestinal segment of six centimeters in length, at a distance of 10 centimeters from the Treitz angle. The 60 animals in the three experimental groups were additionally subjected to ischemia of the vascular pedicle for 30 minutes. The control group and the experimental group GIREI7 were evaluated on the 7th day after the operation. The groups GIREI14 and GIREI28 (which also underwent ischemia) were utilized to evaluate the evolution of the lesion over time, on the 14th and 28th days after the operation, respectively. From the intestinal excluded loop, we take one ring of 0,5 cm distal and proximal, that were fixed in formaline 10% solution in order to do histological (HE) and immuno-hystochemial (PS-100) evaluation (enteric nervous system.) The distal loop was exteriorized in stoma and the proximal part closed with polipropilene 6-0. RESULTS It was observed a decrease in the number of ganglionic cells in the myenteric plexus in the group subjected to ischemia and reperfusion (GIREI7), in relation to the control group (GCEI7) at the 7th post-operative day (Mann-Whitney test: p = 0.0173 *. Comparing the numbers of ganglionic cells in the myenteric plexus before and after jejunal loop exclusion GCEI7 - (Wilcoxon test: p = 0.0577). GIREI7 - Comparing the numbers of ganglionic cells in the myenteric plexus before and after ischemia (*p = 0.0399). Comparing the percentage variations in ganglionic cells in the myenteric plexus on the 7th, 14th and 28th days after the procedure, in the groups GIREI7, GIREI14 and GIREI28, it was observed that there were no significant alterations. Kruskal-Wallis test: p = 0.6501. CONCLUSION There was a decrease in the number of ganglionic cells in the myenteric plexus due to ischemia and reperfusion that did not recover in the late post-operative period.

Variation of the Rex shunt for treating concurrent obstruction of the portal and superior mesenteric veins

Children with extrahepatic portal vein obstruction can be managed successfully by surgical intervention and should be evaluated for potential meso-Rex bypass. A Rex shunt variation is described to treat portal and superior mesenteric vein thrombosis. This technique uses the internal jugular vein as a conduit between the splenic vein and the left portal vein with splenic preservation.

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

PURPOSE 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.