Scielo RSS <![CDATA[Acta Cirurgica Brasileira]]> vol. 33 num. 9 lang. en <![CDATA[SciELO Logo]]> <![CDATA[Influence of low-level laser irradiation on osteocalcin protein and gene expression in bone tissue<sup>1</sup>]]> Abstract Purpose: To evaluate osteocalcin gene and protein expression in vitro and in an in vivo model of ostectomy. Methods: Twenty Wistar rats were assigned into two groups A (n=10, laser) and B (n=10, control). Ostectomy was performed in the femur diaphysis; the twenty fragments removed, composed in vitro groups named as in vivo (A and B) and cultivated in CO2 atmosphere for thirteen days. Low-level laser irradiation was performed in groups A (in vivo and in vitro) by an GaAlAs device (λ=808 nm, dose of 2J/cm2, power of 200mW, power density of 0.2W/cm2, total energy of 1.25J, spot diameter of 0.02mm) for 5 seconds, at one point, daily. It was performed immunocytochemistry assays in vivo and in vitro groups. In vitro groups were also submitted to RNA extraction, cDNA synthesis and gene expression by quantitative PCR. Statistical analysis was realized with p&lt;0.05. Results: Immunocytochemistry scores showed no significant differences between control and laser groups either in vivo and in vitro. Gene expression also showed no statistical differences. Conclusion: Low-level laser irradiation did not alter osteocalcin protein and gene expression in vivo and in vitro in the studied period but it may have been expressed them in an earlier period. <![CDATA[Role of moxifloxacin-dexamethasone in cardiac histomorphometric findings among Wistar rats from infected mothers]]> Abstract Purpose: To investigate cardiac changes in young rats, whose mothers underwent autogenic fecal peritonitis, during organogenesis phase and to evaluate the role of intravenous administration of moxifloxacin and dexamethasone in preventing infection-related cardiac changes. Methods: A prospective histomorphometric study was performed on 29 hearts of Wistar four-month old rats. Animals were divided into three groups: Negative Control Group (NCG) included 9 subjects from healthy mothers; Positive Control Group (PCG) included 10 subjects from mothers with fecal peritonitis (intra-abdominal injection of 10% autogenic fecal suspension in the gestational period) and did not receive any treatment; and Intervention Group (IG), with 10 animals whose infected mothers received moxifloxacin and dexamethasone treatment 24 hours after induction of fecal peritonitis. Results: Nuclear count was higher in the IG group as compared to PCG (p = 0.0016) and in NCG as compared to PCG (p = 0.0380). There was no significant difference in nuclear counts between NCG and IG. Conclusion: Induced autogenic fecal peritonitis in pregnant Wistar rats determined myocardial changes in young rats that could be avoided by the early administration of intravenous moxifloxacin and dexamethasone. <![CDATA[Oxidative stress on ischemia/reperfusion injury in mice with non-alcoholic hepatic steatosis or steatohepatitis]]> Abstract Purpose: To evaluate the oxidative stress, resulting from ischemia and hepatic reperfusion, in mice with non-alcoholic hepatic steatosis and steatohepatitis. Methods: C57BL/6 male mice were used. Part of them were ob/ob mice, and the other part was fed with standard or MCD diets - this last used to develop steatohepatitis. The animals - MCD-I/R, ob/ob-I/R and I/R groups - were submitted to 30 minutes of partial hepatic ischemia, followed by reperfusion for 24 hours. The blood was collected, for biochemical analysis of AST, and the liver removed for assessment of TBARS and nitrite, and of histology. Results: After the I/R, the animal fed with MCD diet presented higher AST levels (MCD-I/R: 967±349U/L / ob/ob-I/R: 606±18 U/L / I/R: 311±172 U/L), TBARS (MCD-I/R: 7±1 nM/mg protein / ob/ob-I/R: 3±1 nM/mg protein / I/R: 3±1 nM/mg protein) and nitrite (MCD-I/R: 614±87 µg/mL / ob/ob-I/R: 512±81 µg/mL / I/R: 459±29 µg/mL) than the ob/ob mice, when both groups were compared to animals fed with standard diet. Regarding histology, the steatosis level (azonal macrovesicular steatosis of level 3 - &gt;66%) and hepatic fibrosis (periportal and perisinusoidal of level 2) was also more intense, but both animal models presented lobular inflammation of level 3 (&gt;66%). Conclusions: The murine model fed with MCD diet is suitable for the assessment of oxidative stress in hepatic I/R injury associated with the nonalcoholic fatty liver disease. Although both murine models showed inflammatory infiltrate and macro and micro vesicular steatosis. <![CDATA[Tissue microarray technology and collagen evaluation to analyze surgical trauma performed with usual blade or ultrasonic harmonic scalpels in rats]]> Abstract Purpose: To compare wound healing performed with cold blade (CSB) and ultrasonic harmonic scalpel (UHS) in the abdominal aponeurosis of rats. Methods: Eighty Wistar rats divided into two groups and underwent midline incision in the linea alba with cold blade and harmonic ultrasonic scalpel. Analysis were performed in subgroups of 10 animals after 3, 7, 14 and 21 days. Macroscopically was observed the presence of hematoma, infection, wound dehiscence, fistula and adherences. Microscopically were used collagen and immunohistochemical staining methods. Results: Macroscopic, complications showed no statistical difference. Immunohistochemical analysis for MMP-9 was more intense in UHS group (p&lt;0.05). TGF β presented its lower expression in UHS group at 14 and 21 days, with no statistical difference at 3 and 7 days (p&lt;0.05). α-AML expression appeared higher in UHS group after 14 days and remained similar in others (p&lt;0.05). Collagen deposition had no change in type I, and increased in type III in UHS; at 7th day the deposition was higher in CSB group; at 14th was similar in both groups (p&lt;0.001). Conclusion: UHS compared to the CSB has higher lesion area at the time of the incision; as well as it led to the delay of regeneration and scar maturation process. <![CDATA[Rivastigmine prevents injury induced by ischemia and reperfusion in rat liver]]> Abstract Purpose: To evaluate whether pre-treatment with rivastigmine is able to attenuate the I/R induced lesions in rat liver. Methods: SHAM animals or those submitted to I/R, non-treated or pre-treated with rivastigminine (2mg/kg) either 50 or 15 minutes before ischemia, were used. After I/R protocol, these animals were killed and their livers were harvested to measurement of the mitochondrial swelling as well as the malondialdehyde (MDA), nitrite and nitrate tissue concentration. Blood was also harvested for serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) determinations. Results: I/R promoted a significant increase of mitochondrial swelling in the studied animals. This increase of mitochondrial swelling was partially prevented by rivastigmine, but only if administered 50 minutes before ischemia. No significant modification of MDA, nitrite or nitrate tissue concentrations was observed in consequence of I/R, followed or not by rivastigmine treatments. In addition, I/R elevated both AST and ALT. These elevations of serum enzymes were not reversed by the different rivastigmine treatments. Conclusions: Rivastigmine administered 50 minutes before ischemia attenuates I/R-induced mitochondrial swelling, that indicates liver injury. This protective effect may be related to a greater stimulation of α7nAChR present in the Kupffer cells by the non-methabolized ACh, leading to an attenuation of I/R-induced inflammation. <![CDATA[Intravascular and intraparenchymatous hepatic segmentary sclerosis]]> Abstract Purpose: To evaluate the morphological effects of injected sclerosing agents into the liver. Methods: This study was performed on twenty dogs, distributed into five groups: Group 1 (n = 5) - control, Group 2 (n = 5) - injection of 50% glucose solution inside hepatic parenchyma and animals followed during seven days, Group 3 (n = 10) - injection of ethanol inside hepatic parenchyma and animals distribution into two subgroups Subgroup 3A (n = 5) - followed during 24 hours and subgroup 3B (n = 5) - followed during seven days (group 3B), Group 4 (n = 5) - ethanol injection inside left portal vein branch and followed during 24 hours. Livers were macroscopically evaluated, submitted to hepatic arteriography and portography, then histology. Results: All animals in Group 4 died within 23 hours due to diffuse hepatic necrosis. The animals of groups 2 and 3 had a satisfactory evolution. Fibrosis formed in the segment reached by the sclerosant solution and interruption of the contrast flow injected into the portal system. Conclusion: Intrahepatic parenchymal ethanol injection is well tolerated and causes sclerosis restricted to a specific segment; however, intraportal ethanol injection causes massive hepatic necrosis and can lead to death. <![CDATA[Comparative study of fibrosis induced by Marlex<sup>®</sup>, Parietex Composite<sup>®</sup>, Vicryl<sup>®</sup> and Ultrapro<sup>®</sup> meshes<sup>1</sup>]]> Abstract Purpose: To evaluate the fibrosis induced by four different meshes: Marlex®, Parietex Composite®, Vicryl® and Ultrapro®. Methods: Histological cutouts of abdominal wall were analyzed with polarized light 28 days after the meshes implants and colorized by picrosirius to identify the intensity of collagen types I and III, and their maturation index. Results: When the four groups were compared, the total collagen area analyzed was bigger in groups A and D, with no difference between them. The collagen type I density was bigger in group A, with an average of 9.62 ± 1.0, and smaller in group C, with an average of 3.86 ± 0.59. The collagen type III density was similar in groups A, B and C, and bigger in group D. The collagen maturation index was different in each of the four groups, bigger in group A with 0.87, group B with 0.66, group D with 0.57 and group C with 0.33 (p = 0.0000). Conclusion: The most prominent fibrosis promotion in the given meshes was found on Marlex® (polypropylene mesh) and the Parietex Composite® (non-biodegradable polyester); the collagen maturation index was higher in the Marlex® mesh, followed by Ultrapro®, Parietex Composite® and Vicryl® meshes. <![CDATA[Wound healing of diabetic rats treated with <em>Moringa oleifera</em> extract]]> Abstract Purpose: To evaluate if Moringa oleifera leaf aqueous extract (ME) influences the healing of skin wounds of diabetic rats. Methods: Wistar rats were used (6 rats/group). Group 1 received normal saline (NS) v.o. Group 2 received moringa extract (100mg/kg v.o) for 3 weeks. Groups 3 and 4: Streptozotocin (STZ) induced diabetes. Group 3 received NS; Group 4 received aqueous ME (100mg/kg) v.o.The wounds of groups 1 and 3 rats were topically treated with NS; wounds of groups 2 and 4 treated with 200µL of 10% ME. After anesthesia, all rats had skin square excision wounds 1.5cm2. Wound percent contractions were measured. On 10th day, blood glucose and serum cytokines were measured. Histometry of wounds was studied using ImagePro6.0 software. Results: Glycemia was significantly reduced in ME treated rats. These rats had higher percent contraction of the wounds on 2nd, 5th and 10th days, then controls (p&lt;0.05). Diabetic rats treated with NS had TNF-α, IL-1β and IL-6 expression higher than in rats receiving ME. The histopathological score of ME treated diabetic rats (198±13.7) was significantly higher than treatment with NS (145±10.5). Conclusion: ME extract positively influenced healing of wounds in diabetic rats after systemic and topical treatment. <![CDATA[Oxidative stress effects in the uterus, placenta and fetus of pregnant rats submitted to acute and chronic stress]]> Abstract Purpose: To evaluate the effects of oxidative stress in pregnant rats submitted to acute and chronic stress, relating to alterations in the uterus, placenta and fetus. Methods: Twenty-four female Wistar albino (Rattus norvegicus), were divided into four groups, for induction of oxidative stress the animals were submitted to cold and physical immobilization. Plasma fasting glucose and MDA were determined in all groups and the fetuses and placentas were measured. Results: There were no statistical differences in the levels of malonic dialdehyde (MDA), however the averages of chronic stress group were higher compared to control groups, which could explain the observed adverse effects; there was no correlation between puppies’ size, the weight of the placenta and MDA values. Conclusions: Chronic stress causes adverse effects, when compared to control groups; chronic stress group had fetuses, placentas and number of puppies, significantly lower compared to other groups. The rats exposed to chronic stress, also presented a higher frequency of fetal resorption. <![CDATA[Potencial of different hydroxyapatites as biomaterials in the bone remodeling]]> Abstract Purpose: To analyze the therapeutic potentials of different hydroxyapatites used for the correction of bone defects in rats. Methods: Forty rats, male, albino wistar, were distributed in 4 groups. They were submitted to a 3.5 mm defect in tibia. They received low purity hydroxyapatite, Strontium hydroxyapatite and hydroxyapatite doped with gallium, having a seven day evaluation time. Histopathology slides were stained with hematoxylin-eosin, for morphological evaluation. Were analyzed inflammatory processes, necrosis, presence of osteoclasts and osteoblasts, presence of the material, presence of white cells, neovascularization and bone neoformation. Results: It was observed that the groups HAPSr and HAPGa, presented better results of trabecular bone, hyaline cartilage and bone marrow more organized. Conclusion: There was improvement in the repair of the bone defect produced, showing that these hydroxyapatites are effective osteoinductive, osteoconductive, osteintegrant agents and have biocompatibility, and may be indicated for use in defect repairs. <![CDATA[Hyperbaric oxygenation on adhesions prevention after laparotomy in rats]]> Abstract Purpose: To evaluate the effects of hyperbaric oxygenation on prevention of adhesions in the abdominal cavity after laparotomy. Methods: Fifty four rats underwent laparotomy; stitches were made in the four quadrant parietal peritoneum and abdominal cavity closure. Animals were divided into three groups: 1 - control; 2 - subjected to high pressures and oxygenation; 3 - subjected to 100% hyperbaric oxygenation. The animals in groups 2 and 3 were daily submitted to oxygenation hyperbaric chamber after surgery. On the seventh day another laparotomy, registration of procedure, assessment of adhesions and biopsies of the peritoneum were held. Professionals analyzed the videos and the biopsies. Results: Peritoneal cavity adhesions occurred in animals of three groups with no difference between them. In Group 3, the adhesions presented more fragile and vascular proliferation more pronounced, and there was no difference in comparison with the first and second groups. However, there was no significant difference in the evaluation of these parameters between the animals in groups 1 and 2. Conclusions: Postoperative hyperbaric oxygenation in rats submitted to laparotomy did not alter the frequency, but reduced the density of adhesions in the peritoneal cavity and promoted vascular proliferation. The change in atmospheric pressure alone had no influence on the results. <![CDATA[Preservation of the vagus nerves in subtotal esophagectomy without thoracotomy]]> Abstract Purpose: To evaluate the outcome of transhiatal esophagectomy without thoracotomy and with preservation of the vagal trunks for the treatment of advanced megaesophagus. Methods: Between March 2006 and September 2017, it was performed 136 transhiatal esophagectomies without thoracotomy by laparoscopy, with preservation of the vagus nerves. All patients were evaluated pre and postoperatively for respiratory and nutritional aspects Post operatively, some surgical aspects were evaluated like radiology and endoscopy of the digestive tract. Results: Follow-up for 7 months to 12 years by clinical, radiologic, endoscopic and pH monitoring revealed satisfactory and encouraging outcomes of the procedure. Conclusion: The laparoscopic transhiatal esophagectomy is a feasible and safe technique with good postoperative outcomes. <![CDATA[Experiences with basic microsurgical training programs and skill assessment methods at the University of Debrecen, Hungary]]> Abstract During the past decades microsurgical training programs together with skill assessment methods had been developing intensively worldwide. Concerning the teaching of basic techniques at various levels, we aimed to summarize the education program types and experiences at our department, in order to define the way of continuity. All in the hope that this summary might contain useful information for other educators as well. About 50 years ago, in the late 1960s, microsurgical basic education had been established in Debrecen. Since the 1990s multilevel education programs have been developed, starting in undergraduate years up to the postgraduate training, residency and continuous medical education programs. In the last three decades about 2,300 participants completed courses, including over 470 residents. The ones who already succeeded microsurgical course as medical students, during residency program could reach better results and skill development. Concluding thoughts, the traditional methods and special experiences are highly important in microsurgical education. The necessary duration and individual training approach are emphasized. Standardization (self and international), comparability, accessibility, providing milestones of microsurgical skills are key factors. Proper feedback and skill assessment (experiences, internationally recognized scores, or combinations) are indispensable, but have to be fitted to the characteristic elements of the course. <![CDATA[A technical note on low cost rat laparoscopy an initial experience]]> Abstract Purpose: To evaluate a novel and adapted low-cost set model for laparoscopic surgery in rats. Methods: Nine Wistar rats underwent two different laparoscopic procedures, splenectomy (n=3) and distal pancreatectomy with splenectomy (n = 6), after assembling a low-cost set replacing the conventional one (monitor, micro camera, image processor, light source, laparoscope and insufflator). The new set included an Android Tablet 10.5 ", a 5mm USB Endoscope and semiautomatic sphygmomanometer monitor. Results: The same surgeon performed the laparoscopic procedures. Total surgical time ranged from 36 to 60 minutes with a mean of 45.8 minutes. Three rats died during the distal pancreatic and splenectomy procedure (33.3%), due to respiratory failure (n = 1), uncontrolled abdominal hemorrhage (n=1) and iatrogenic gastric perforation (n = 1). We followed the other six rats (66.6%) for seven days with no further evidence of complications. Conclusions: The laparoscopic partial pancreatectomy and splenectomy can be performed with the novel low-cost set assembled in the present experimental study. Both specific training and skills development are required to validate more advanced laparoscopic procedures and achieve a desirable outcome. <![CDATA[New trends in translational microsurgery]]> Abstract Technological advances such as optical instruments and surgical tools have enabled the considerable contributions of microsurgery to surgical therapies. Accordingly, surgical therapeutics has provided the latest information across a wide range of medical specialties, including immunology and pharmacology, despite specialization according to organs and organ systems. The International Society for Experimental Microsurgery, an academic organization, has utilized experimental microsurgery technology in the identification of curative concepts for diseases that remain difficult to treat. For this publication to mark the 32nd anniversary of the Brazilian Surgical Society, I introduced the following types of technology related to the further development of microsurgical technological innovations in the future: high-resolution three-dimensional (3D) video and touch-sensitive microsurgery robots.