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Purpose:: To compare the two lines suture (total and seromuscular) after partial gastrectomy in normal and overweight rats., Methods:: Forty Wistar rats were distributed in two groups. Group A received normal diet; group B, normal diet and supplementation with saccharose in the water. When group B progressed to a statistically greater weight than the animals of group A, the experiment (sleeve-like gastrectomy) was conducted with gastrorraphy in two sutures lines (total and seromuscular).The animals were distributed into two subgroups of 10. A1 and A2 subgroups were sacrificed at 7 and 14 days postoperatively as well as B1 and B2. Mortality, morbidity, complications attributed to the gastric suture, biochemical dosages, Lee index, macroscopy, weight of retroperitoneal and gonadal fat, optical microscopy with hematoxylin-eosin and picrosirius-red, were the evaluation parameters., Results:: The overweight group achieved statistically greater weight after 16 weeks in induced obesity; there was no mortality or complications with clinical consequences attributable to morbidity. The overweight group had statistically greater weight of gonadal and retroperitoneal fat. The difference was observed in urea, albumin, total cholesterol and indirect bilirubin., Conclusion:: There was no outcome difference between the overweight and non-overweight group in two suture lines in gastrorrhaphy after sleeve-like gastrectomy.

Objective: To evaluate the influence of oral supplementation with arginine on regeneration of injuries due to straining of the anterior tibial muscle of rats., Methods: Twenty-four Wistar rats of weight 492.5 ± 50.45 g were used. Injuries were induced through straining the anterior tibial muscles. The rats were separated into three groups of eight rats each. In the untreated group (UTG), after induction of injuries, the rats were observed for 24 h. In the simulation group (SG) and the arginine group (AG) respectively, the rats received isotonic saline solution and arginine solution via direct gavage, over a seven-day period. At the end of the period, blood samples were collected for serum evaluations of creatine kinase (CK), lactic dehydrogenase (LDH), aspartate aminotransferase (AST) and C-reactive protein (CRP). The right and left anterior tibial muscles were resected for histopathological evaluations on the muscle injuries, investigating edema, hemorrhage and disorganization or morphometric alteration of the muscle fibers. The tissue repair was investigated in terms of proliferation of adipose tissue, angiogenesis and collagen fibers. The ANOVA and Student's t methods were used and p ≤ 0.05 was taken to be statistically significant., Results: In the serum evaluations, the AG showed lower CK assay values and higher AST values. In the histopathological evaluation, the UTG presented edema and hemorrhage compatible with injuries due to strain; the SG presented edema and hemorrhage with proliferation of adipose tissue and collagen fibers; and the AG presented not only the findings of the SG but also, especially, intense angiogenesis., Conclusion: Oral supplementation with arginine did not cause any significant metabolic alterations that would contraindicate its use and it induced angiogenesis during the repair of muscles injured due to strain.

Purpose: To evaluate the synthesis of type I (mature) and type III (immature) collagen in bladder suture of rats treated with a combination of tacrolimus and mycophenolate mofetil for 15 days., Materials and Methods: Thirty rats were divided into 3 groups: the sham, control and experimental groups. All the animals underwent laparotomy, cystotomy and bladder suture in two planes with surgical PDS 5-0 thread. The sham group did not receive treatment. The control group received saline solution, and the experimental group received 0.1mg/kg/day of tacrolimus with 20mg/kg/day of mycophenolate mofetil, for 15 days. From then on, the tacrolimus was dosed. The surgical specimens of the bladder suture area were processed so that the total type I and type III collagen could be measured by the picrosirius red technique., Results: There was a predominance of type I collagen production in the sham and control groups compared to the experimental group, in which type III collagen was predominant. The production of total collagen did not change., Conclusion: The association of tacrolimus and mycophenolate mofetil in animals qualitatively changes the production of collagen after 15 days with a predominance of type III collagen.

Objective: To compare bacterial growth in pure colostrum versus colostrum with human milk fortifier (HMF) containing iron., Methods: The growth of Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa in 78 samples of pure colostrum or colostrum with added iron-containing HMF was compared. For qualitative analysis, filter paper discs were immersed in samples from each group and incubated for 48 hours with 10(1) colony forming units (CFUs)/mL of each strain. For quantitative assessment, 1 mL of each strain containing 10(7) CFUs/mL was homogenized with 1 mL of either colostrum or colostrum with human milk fortifier, seeded into a Petri dish, and incubated at 37°C. Twenty-four hours later, the number of CFUs was counted., Results: The qualitative analysis showed no difference in bacterial growth. In the quantitative evaluation, E. coli growth in the control group was 29.4±9.7×10(6)CFU/mL, while in the HMF group it was 31.2±10.8×10(6)CFU/mL. The difference between the average growth was 1.9±4.9×10(6)CFU/mL (p=0.001). There were no differences in S. aureus and P. aeruginosa growth., Conclusion: Addition of iron at this concentration reduces breast milk bacteriostatic action against E. coli., (Copyright © 2013 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.)

Objective: To evaluate whether treatment with L-arginine influences the healing of skin flaps in rats exposed to nicotine., Methods: 40 male Wistar rats weighing 142.4 ± 10.1 g were separated into four groups: GC: treatment with 7.4 pH phosphate buffer, submitted to skin flap and observation for ten days; GN: exposure to nicotine for four weeks, submitted to skin flap and observation for ten days; GA: treatment with 7.4 pH phosphate buffer for four weeks, submitted to skin flap and arginine treatment for ten days; GAN: exposure to nicotine for four weeks, submitted to skin flap and treatment with arginine for ten days. We evaluated: areas of necrosis, re-epithelialization, inflammatory reaction and formation of granulation tissue by HE stain; the total area of deposition and differentiation of collagens I and III by histometry with picrosirius staining; and the scar vascular density by immunohistochemical staining with monoclonal anti-CD34 antibodies., Results: The percentages of necrotic areas in GN and GNA were higher (p <0.001) than in GC and GA. In histological scores, collagen deposition, and the percentage of type I collagen, GA and GC were similar to each other (p> 0.05), but higher (p <0.001) than GA and GNA; as for vascular densities, they were lower in GN and GAN (p <0.001) than in GC and GA., Conclusion: Exposure to nicotine inhibited the effects of arginine and in unexposed mice there was induction of angiogenesis and improvement in the total collagen deposition in the skin flaps.

Purpose: To compare sutures with polypropylene and poliglecaprone 25 after partial cecotomy in rats., Methods: Thirty six rats divided into two groups, A and B, of 18 animals; each group was also divided into three subgroups of six animals sacrificed at 4(th), 7(th) and 14(th) days after surgery. Were studied the mortality, morbidity, complications attributable to sutures, macroscopy, optical microscopy and measurement of hydroxyproline at the level of the suture., Results: There were no deaths or wound complications such as hematoma, seroma, abscess, evisceration or eventration. On microscopic evaluation reepithelization, coaptation and inflammation in both groups did not differ significantly. The average rate of tissue hydroxyproline found in the samples on the 4(th) day after surgery, was 21.38 mg/g tissue for group A and 16.68 mg/g for group B; on day 7 after surgery, the average was 15.64 mg/g tissue for group A and 26.53 mg/g for group B; on day 14, the average was 8.09 mg/g tissue for group A and 25.07 mg/g for group B., Conclusion: There were no differences on clinical evolution, macroscopic aspect, microscopic data and hydroxyproline concentration on both sutures.

Introduction: Thiobarbituric acid-reactive substance is a marker of oxidative stress and has cytotoxic and genotoxic actions. C- reactive protein is used to evaluate the acute phase of inflammatory response., Objectives: To assess the thiobarbituric acid-reactive substance and C-reactive protein levels during extracorporeal circulation in patients submitted to cardiopulmonary bypass., Methods: Twenty-five consecutive surgical patients (16 men and nine women; mean age 61.2 ± 9.7 years) with severe coronary artery disease diagnosed by angiography scheduled for myocardial revascularization surgery with extracorporeal circulation were selected. Blood samples were collected immediately before initializing extracorporeal circulation, T0; in 10 minutes, T10; and in 30 minutes, T30., Results: The thiobarbituric acid-reactive substance levels increased after extracorporeal circulation (P=0.001), with average values in T0=1.5 ± 0.07; in T10=5.54 ± 0.35; and in T30=3.36 ± 0.29 mmoles/mg of serum protein. The C-reactive protein levels in T0 were negative in all samples; in T10 average was 0.96 ± 0.7 mg/dl; and in T30 average was 0.99 ± 0.76 mg/dl. There were no significant differences between the dosages in T10 and T30 (P=0.83)., Conclusions: C-reactive protein and thiobarbituric acid-reactive substance plasma levels progressively increased during extracorporeal circulation, with maximum values of thiobarbituric acid-reactive substance at 10 min and of C-reactive protein at 30 min. It suggests that there are an inflammatory response and oxidative stress during extracorporeal circulation.

Objective: To determine whether tacrolimus administered to rats, in the presence of pancreatitis induced by L-Arginine, interferes with the serum levels of amylase and glucose and the histological pattern of the pancreatic parenchyma., Methods: Forty Wistar rats were divided into four groups with 10 rats each: control group (C), tacrolimus group (T), pancreatitis group (P) and pancreatitis-tacrolimus group (PT). We evaluated serum levels of amylase, glucose, and tacrolimus and made histological assessments of the pancreas. Induction of pancreatitis was made by inoculation of L-Arginine at a dose of 500 mg/100g body weight intraperitoneally, and tacrolimus treatment at a dose of 1ìg/kg subcutaneously for four days., Results: Serum amylase was higher (p = 0.0000) in groups PT, P and T than in the control group. The PT group mean was higher (p = 0.0009) than in the T group, but did not differ (p = 0.6802) from the average of the P group. There was no difference between groups P and T (p = 0.2568). Neither in mean blood glucose between the groups (p = 0.4920); serum levels of tacrolimus were similar in PT and T groups (p = 0.7112). There were no histological changes in groups T and C and no hemorrhage in the pancreas of rats in groups P and PT. In group P, there was no edema in 30%, mild edema in 20% and in 50%, moderate; as for inflammatory infiltration, it was moderate in 80% and absent in 20%, and atrophy of the parenchyma was moderate in 60% and severe in 40%. In the PT group, there was edema, inflammatory infiltration or atrophy in the pancreas in all rats., Conclusion: Treatment with Tacrolimus induced an increase in serum amylase in normal mice, but did not affect blood glucose or the histological pattern of the pancreatic parenchyma. In the presence of pancreatitis induced by L-Arginine tacrolimus induced edema, inflammatory infiltration and more severe atrophy in the pancreatic parenchyma.

Purpose: To study the collagen density and the population of fibroblasts in cutaneous injuries in rats under the influence of nicotine., Methods: The scars of abdominal wounds in rats were analyzed. 2 mg/kg/d of nicotine was administered to the animals in the experiment group and the solution used as a vehicle for the animals in the control group. Treatment was begun seven days prior to surgery and maintained for seven or fourteen days following surgery. The removed scars were prepared for histopathological study. Histological cuts were stained by Sirius Supra red F3BA for collagen analysis and submitted to the examination using the immunohistochemical technique, which enabled us to recognize the population of fibroblasts., Results: No significant difference was found in type I collagen density after seven days (p=0.912), nor after fourteen days (p=0.211). The control group had more type III collagen after seven days (p=0.004), but after fourteen days there was no significant difference (p=0,720). The total quantification of collagen, although higher in the control group, was not significantly so at any time during the study (p=0.103 after seven days and p=0.549 after fourteen days). The average of fibroblasts per field was lower after seven days (p=0.0001) and after fourteen days (p=0.0000)., Conclusion: Under the conditions of this experiment, nicotine reduced the fibroblast population without modifying collagen density significantly.

Objective: To study the inflammatory reaction and deposition of collagen in the healing of cutaneous injuries under the influence of nicotine., Methods: The scars of abdominal injuries in rats were analyzed, which had been treated with nicotine, 2 mg/kg/d, and compared with those of control rats. Treatment was begun seven days prior to operation and was maintained for seven or fourteen days after surgery. The histological cuts were stained with hematoxylin and eosin and through the established scores the intensity and type of inflammatory reaction was identified. Histological cuts stained by Sirius Supra red F3BA enabled the identification of the collagen density., Results: There was no difference in intensity of the inflammatory reaction after seven days (p=0.165), nor after fourteen days (p=0.684). There was no significant difference in the type I collagen density in the evaluation carried out after seven days (p=0.912) and after fourteen days (p=0,211). The control group had more type III collagen after seven days (p=0.004), but after fourteen days there was no significant difference (p=0.720). Although the total quantification of collagen was higher in the control group, there was no significant difference at any time during this study (p=0.103 after seven days and p=0.549 after fourteen days)., Conclusion: In the scars of the animals treated with nicotine in comparison with the control group, there was no difference in the intensity of the inflammatory process, nor in collagen density.

Colonic anastomosis healing in hypothyroidism was evaluated. Twenty Wistar rats were separated into two groups: the study group (n = 10), which underwent total thyroidectomy to induce hypothyroidism, and the control group (n = 10). After 10 weeks, hypothyroid status was confirmed by blood tests (p < 0.0001). Three days later, a colonic anastomosis was performed, and the animals were sacrificed 1 week later. The colon containing the anastomosis was resected for bursting strength tests and histological studies. The slides were stained with hematoxylin-eosin and with Sirius red to quantify and classify the collagen. Reduced values were found for the bursting strength test (p = 0.0006) and for collagen density in the experimental group. There was a prevalence of immature type III collagen (p < 0.0001) and a decrease in mature type I collagen (p < 0.0001) in the hypothyroid group., (Copyright 2009 S. Karger AG, Basel.)

This study tested the hypothesis that the use of corticosteroids prior to antibiotics can lower the mortality rate in severe infections by S. aureus or Gram-negative bacilli, using an animal model. This study was a prospective and controlled study, placed in a university laboratory. Seven hundred and sixty mice distributed into three groups (Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae infected). The interventions in each group were: I) infection control (intra-peritoneal); II) treatment solely with antibiotics (teicoplanin or amikacin); III) antibiotics administered prior to the corticosteroid (methylprednisolone); IV) antibiotics administered after the corticosteroid. Mortality in the E. coli group, subgroup I: 100%; subgroup II: 55% (p<0.001); subgroup III: 62.5% (p=0.2488, compared to subgroup II); subgroup IV: 20% (p<0.01 compared to subgroups II and III). Mortality in the K. pneumoniae group: subgroup I: 100%; subgroup II: 72.5% (p<0.01); subgroup III: 80% (p=0.215 compared to subgroup II); subgroup IV: 45% (p<0.01 compared to subgroups II and III). Mortality in the S. aureus group: subgroup I: 82.5%; II: 42.5% (p<0.001); subgroup III: 77.5% (p=0.2877 compared to subgroup I); subgroup IV: 32.5% (p=0.1792 compared to subgroup II). The use of corticosteroids prior to antibiotics lowered the mortality rate caused by Gram-negative bacteria and did not affect the mortality caused by S. aureus. When used after starting treatment with antibiotics, the corticosteroid was not superior to the use of antibiotics alone in the case of the Gram-negative bacteria, and was not significantly different from non-treatment of the infection, in the case of S. aureus.

Introduction: Esophagojejunostomy after total gastrectomy still remains a high risk anastomosis with a considerable morbidity and mortality. The majority of these anastomoses are performed by the intraluminal stapler technique, yet stenoses are a known late complication even after an uneventful postoperative course. In the present study, the osophagojejunostomy with the biofragmentable anastomosis ring (BAR) was examined in dogs., Methods: 28 dogs were randomized into a group of manual suture (n = 14) and a BAR-group (n = 14). After gastrectomy, the esophagojejunostomy was performed by hand-suture with polypropylene 4-0 in the manual suture group, and with the 25/1.5 mm BAR in the BAR-group. In both groups the Roux-en-Y jejunojejunostomy was performed by hand-suture. The dogs were evaluated on postoperative days 4, 7 and 14 with regard to macroscopy, bursting strength, tissue hydroxyproline and histology., Results: There was one leakage without clinical effect in the hand-sewn group on postoperative day 4; there was no leak in the BAR-group. In observing fibre-free enteral feeding, neither functional disorders nor obstruction of the BAR were observed. The general anastomosis parameters were matchable between the groups., Conclusion: The infracarinal BAR-esophagojejunostomy is comparable to the hand-sewn anastomosis in the dog-model.

Background: Excessive doses of basic amino acids such as L-arginine are able to injure the pancreas of rats., Aim: To describe and evaluate the biochemical and histological characteristics of acute pancreatitis in rats induced by L-arginine during the installation, development and repair stages of the pancreatic inflammatory process. MATERIAL AND METHODS - The study group consisted of 105 male Wistar rats. The rats in the experimental group (n = 70) received 500 mg/100 g of corporal weight L-arginine injection intraperitoneally. In the control group (n = 35), isotonic saline solution was injected. Ten rats in the experiment group and five in the control group were analyzed after 6, 12, 24, 48, and 72 hours, on the 7th and 14th days. During those times, blood samples were collected for laboratory testing and samples from the pancreas were collected for an optical microscopy analysis., Results: From 12 to 24 hours after the injection of L-arginine, the amylase serum levels raised to their peak values when compared to the rats in the control group, decreasing gradually, reaching an equal level after the 48th hour and being significantly lower after 72 hours and 7 days. The enzymatic activity returned to its basal level after 14 days. The amylase values were normal in all the times evaluated in the control group. In optical microscopy, after the injection of L-arginine, a pancreatic architecture histologically preserved was observed after 6 hours, evidencing an important interstitial edema in 24 hours. After 48 hours, the acinar architecture was partially destroyed with focal cellular necrosis, reaching its maximum severity after 72 hours. On the 7th, the tissue necrosis and the edema had diminished, and the regeneration of the acinar architecture initiated. The pancreatic structural reconstruction could be observed after 14 days. Pancreatic histological changes were not found in the control group., Conclusion: - Experimental acute pancreatitis induced by L-arginine leads to pancreatic necrosis showing self-limited evolution with pancreas regeneration in 2 weeks.

Background: Study the effects of splenectomy on the intra-abdominal infection by bowel flora, consequent to a colonic injury in Wistar rats., Methods: We used 64 animals, 20 for Group A1 (normal with colon lesion left open), 22 for Group A2 (normal with colon lesion sutured) and 22 for Group B (spleen removed). The animals were submitted to a laparatomy through a midline abdominal incision and peritonitis was induced by a colonic lesion in the colon previously distended with 2 ml of saline introduced in the rectum. Bacteriological studies of the abdominal wash obtained with a sterilized swab and microscopic studies of samples of the segment of the sutured colon obtained at 48 hrs, 96 hrs and on the 12 post op day, were made in each group. All rats were submitted to an autopsy on the day of death or on the 12th post op day when the survivors were sacrificed., Results: Similar bacteria were found in the three groups. E. coli (100%); Enterococcus fecalis (97%); Klebsiela pneumoniae (70%); Citrobacter freundi (70%) and Enterobacter aglomerans (63%). In the first 96 hours the rats without spleen had a lesser inflammatory reaction when compared to the group with spleen. The leading cause of death was generalized peritonitis in the first 96 hours. There was a significant statistical difference in the mortality rate between Group B (80%), Group A2 (no mortality) and Group A1 (35%)., Conclusion: There was a significant statistical difference in the mortality rate caused by peritonitis between the groups with splenectomy when compared to the group with no splenectomy.

In the present study, the Billroth-I anastomosis with the biofragmentable anastomosis ring was examined in dogs. 24 dogs were randomized into a group of manual suturing (n = 12) and a BAR-group (n = 12). In the group of manual suturing, a distal gastric resection and gastroduodenostomy with sero-submucous suture was performed. In the BAR-group, the distal gastric resection was done with the linear stapler PLC-75, whereby the BAR gastroduodenostomy crossed the stapling line. The dogs were evaluated on p.o. days 4, 14, and 30 and tested for bursting strength and bursting location, appearance of mucosa, hydroxyprolin concentration, and histologic features. There was no functional disorder in the gastrointestinal transit in any animal; in summary with regard to the various parameters, the crossing of BAR and stapling line does not represent any additional risk factor in the Billroth-I anastomosis in dogs.

In order to know the left colon anastomosis evolution with perforation and focus peritonitis, 40 male rats, Wistar-TECPAR, 135 days old and weighing 345 g in average were divided in two groups of 20 animals each. Group A was the control group and group B the experimental group. Submitted to a laparotomy, the B rats had a left colon wound 0.3 cm in diameter, 1.5 cm in distance from the peritoneal reflection. The A rats had only a intestinal handling. All rats had a new laparotomy after 24 hours; a resection and end-to-end anastomosis. An analysis was made on third and seventh days of the macro and microscopic evolution and bursting pressure. On the second laparotomy, in the B rats, peritonitis was absent and only local reaction was present. Dehiscence, fistula or peritonitis were absent at the observation on the third and seventh days. The anastomosis evolution was similar in the two groups. It was concluded that the focus peritonitis was not sufficient to modify the healing process of the left colon anastomosis in rats during the period studied.