Resumo em Inglês:

PURPOSE: To describe an experimental model of cutaneous radiation injury in rabbits. METHODS: On this study eight six-month-old New Zealand male rabbits, with an average weight of 2.5kg were used. They were distributed in four groups (n=2 per group). The control group did not receive radiotherapy and the others received one radiotherapy session of 2000, 3000 and 4500 cGy, respectively. Photographic analysis and histopathological evaluation of the irradiated areas were carried out. RESULTS: After 30 days, the animals from the control group had all their hair grown. In spite of that, the animals from group 2000 cGy had a 60-day alopecia and from group 3000 cGy, a 90-day alopecia. After the 30th day, the 3000cGy group demonstrated 90-day cutaneous radiation injuries, graded 3 and 4. One of the animals from group 4500 cGy died on the 7th day with visceral necrosis. The other from the same group had total skin necrosis. A progressive reduction of glands and blood vessels count and an increase on collagen deposition was observed. CONCLUSION: The proposed experimental model is reproductable. This study suggests that the dosage 4500cGy is excessive and the 3000 cGy is the most effective for this experimental model of cutaneous radiation injury in rabbits.

Resumo em Inglês:

PURPOSE: To fabricate a three-dimensional biomodels of intracranial aneurysms, using rapid prototyping technology, to facilitate optimal anatomical visualization of aneurysms prior to and during surgery. METHODS: Four intracranial aneurysms cases were selected for this study. Using CT angiography images, the rapid prototyping process was completed using a PolyJet technology machine. The size and morphology of the prototypes were compared to brain digital subtraction arteriography of the same patients. RESULTS: The biomodels reproduced the exact location and morphology of the intracranial aneurysms, particularly the necks, in life-size dimensions and exactly the same as measured by digital subtraction arteriography. The arterial segments adjacent to the aneurysm and arteries anatomically known by the surgeon were also shown, which could guide the surgeon to the aneurysmal segment. The models showed an average unit cost of US$ 130 and each one took an average of 20 hours to be fabricated. CONCLUSIONS: It is possible to fabricate 3D physical biomodels of intracranial aneurysms from CT angiography images. These prototypes may be useful in the surgical planning for intracranial aneurysms to clarify the anatomy, define surgical techniques and facilitate the choice of suitable materials, such as clips and clip appliers.

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PURPOSE: Natural orifice transluminal endoscopic surgery (NOTES) is a new technique. This study describes our initial experience of NOTES and investigates the feasibility of transumbilical endoscopic cholecystectomy (TUEC). METHODS: Eight domestic pigs were submitted to TUEC. After establishment of pneumoperitoneum, a bi-channel endoscope was placed through an infra-umbilical trocar. The gallbladder fundus was lifted by a grasper. The cystic duct and artery was dissected with a flexible hook and clipped by a clip fixing device. The specimen was extracted through the infra-umbilical trocar. RESULTS: The mean operation time was 114 minutes, ranging from 75 to 155 minutes. All the gallbladders were removed successfully. There was one case of subtotal resection, two cases of bleeding and three cases of bile leakage. CONCLUSION: Transumbilical endoscopic cholecystectomy is feasible although it needs more support of experiments and techniques before being applied on human subjects.

Resumo em Inglês:

PURPOSE: To investigate the small intestinal tissue alterations in rats submitted to ischemia and tissue reperfusion using pentoxyfilline or prostaglandin E1. METHODS: Thirty five Wistar rats were used, distributed into group control (A) n=10 were submitted to intestinal ischemia and reperfusion during 60 minutes and no one drug have been utilized. In the group pentoxyfilline (B) n=10 have been utilized during tissue ischemia and reperfusion as well as prostaglandin E1 (C) n=10, but separately. In the group sham (D) n=5, the animals were submitted to surgical. After euthanasia of the animals, a segment of the small intestine was cut, stained by hematoxilin-eosin and histological analysis according to Chiu criteria. RESULTS: Histological results showed that using pentoxyflline or prostaglandin E1 the results during tissue reperfusion were better, since the levels of criteria from Chiu that predominated were level 2 and 3, indicating less tissue damage in comparison to the control group (group A) that showed levels 4 and 5, what means more severe histological tissue alterations. CONCLUSION: Use of pentoxyfilline or prostaglandin E1 promoted a beneficial effect during intestinal reperfusion, demonstrated by less severe histological lesions in the small intestine mucosa of rats submitted to ischemia and tissue reperfusion when helped by the drugs.

Resumo em Inglês:

PURPOSE: To assess the probable actions of ropivacaine, 50% enantiomeric excess bupivacaine mixture (S75-R25) and levobupivacaine on neuromuscular transmission in vitro. METHODS: Thirty rats were distributed into groups (n=5) according to the drug used: ropivacaine, bupivacaine (S75-R25) and levobupivacaine. The concentration used for the three local anesthetics (LA) was 5 µg.mL.-1The following parameters were evaluated: 1) LA effects on membrane potential (MP) and miniature end plate potential (MEPP). A chick biventer cervicis preparation was also used to evaluate LA effects on the contracture response to acetylcholine. RESULTS: LA did not alter MP values and decreased the frequency and amplitude of MEPP. In a chick biventer cervicis preparation, bupivacaine (S75-R25) and levobupivacaine decreased the contracture response to acetylcholine with statistical significance, in comparison to ropivacaine. CONCLUSIONS: In the concentrations used, levobupivacaine and bupivacaine (S75-R25) exhibited presynaptic and postsynaptic actions evidenced by alterations in miniature end plate potentials and contracture response to acetylcholine. Ropivacaine only had a presynaptic action.

Resumo em Inglês:

PURPOSE: To analyze the viability of using Gelpoint® (single-port access) to make partial and total nephrectomy in pigs and to describe the technical difficulties found during these surgical procedures. METHODS: Ten pigs (Landrace specie) with 20kg in average were distributed in two groups. Group A: total right nephrectomy and Group B: partial left nephrectomy. The procedures were performed inside the Surgical Technique Room from Pontifícia Universidade Católica do Parana (PUCPR). RESULTS: In Group A, time to single-port insertion varied from one to two minutes and total time of the procedures were 20.4±8.2 minutes. Bleeding was under than 20 mL in 70% of animals. Time of instrument excision was 20.7±12 seconds and time of hilum dissection was 3.9±2.2 minutes. In Group B, after total contralateral nephrectomy two surgical procedures were not concluded due to bleeding. In this group, time of surgery was 6.8±4.2 minutes. With the exception of the second surgery, the highest blood volume loss was 50 mL. The mean excision time was 22.3 ± 22.3 seconds. CONCLUSION: Total and partial nephrectomy through umbilical single-access using GelPoint® was feasible and safe in pigs.

Resumo em Inglês:

PURPOSE: To evaluate the effects of peritoneal lavage with bupivacaine on survival and initial resistance of anastomosis on distal colon, performed under peritonitis or not. METHODS: Forty rats, weighing from 300 to 350g (321.29±11.31g), were randomly divided in four groups and underwent laparotomy and anastomosis on the distal colon six hours after induction of peritonitis by intraperitoneal injection of autologous fecal material or not. Group 1: No peritonitis and lavage with 3ml NS; Group 2: No peritonitis and lavage with 8 mg.kg-1 (± 0.5 mL) of 0.5% bupivacaine added to 2.5 mL of NS; Group 3: Peritonitis and lavage with 3ml NS; Group 4: Peritonitis and lavage with 8 mg.kg-1 (± 0.5 mL) of 0.5% bupivacaine added to 2.5 mL of NS. Necropsies were performed on the animals that died and the time of death was recorded. Surviving animals were submitted to euthanasia on the fifth post-operative day and Total Energy of Rupture biomechanical test (TER) was applied. RESULTS: Group 4 showed survival increase compared to Group 3, without statistical significance. Group 3 presented the smallest average TER, with statistical significance. CONCLUSION: Peritonitis increased mortality and influenced negatively the resistance of colic anastomosis in rats. Peritoneal lavage with bupivacaine increased anastomotic resistance.

Resumo em Inglês:

PURPOSE: To determine the prevalence of non alcoholic fatty liver disease (NAFLD) and non alcoholic steatohepatitis (NASH) in morbidly obese patients undergoing bariatric surgery and to identify risk factors associated with the disease spectrum. METHODS: Liver biopsy was performed in 60 patients who underwent bariatric surgery, after other causes of liver disease were excluded. Clinical, biochemical and histological features were evaluated. RESULTS: NAFLD was detected in fifty-seven patients (95%) of the sample and forty patients (66.7%) of the total sample met the criteria for NASH. Perisinusoidal fibrosis was only found in three (7.5%) patients with NASH. The γGT was an independent predictive factor associated with the degree of hepatic steatosis. The variables such as dyslipidemia and ALT were independently associated with the presence of Mallory's corpuscles with the following values, respectively, OR 0, 05, 95% CI 0.002 to 0.75, P = 0.031 and OR 10, 99, 95% CI 1.44 to 83.93, P = 0.021. CONCLUSIONS: Non alcoholic fatty liver disease seems to be an obese-related condition with approximately half of asymptomatic morbidly obese patients having histological NASH. The γGT was an independent predictor of the degree of steatosis.

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PURPOSE: To assess venous hemodynamics and quality of life at lest five years after varicose vein stripping. METHODS: We conducted a prospective study with 39 patients (63 limbs) with primary lower limbs varicose veins. Preoperatively, all patients were subjected to clinical evaluation, duplex ultrassound, air plethysmography (APG), and CIVIQ questionnaire of quality of life. By APG, venous filling index (VFI), ejection fraction (EF), and residual volume fraction (RVF) were determined. CIVIQ addresses four domains in course of 20 questions, including states of physical, social, and psychological well-being, and pain level. Varicose veins were treated by standard venous stripping. At least five years after surgery (77.9 ± 10.9 months), patients were reassessed and had clinical examination, duplex ultrasound, APG, and CIVIQ repeated. No late follow-up data was available for 24 patients. RESULTS: Preoperative and late postoperative VFI levels were similar, whereas EF (P=0.05) and RVF (P=0.01), as hemodynamic variables, significantly improved following surgery. In the late postoperative period, overall CIVIQ scores were significantly lower (P=0.005), as were scores in all four domains: pain (P=0.001), physical (P=0.007), social (P=0.008), and psychological (P= 0.05). CONCLUSION: In a small prospective cohort, improvements in venous hemodynamics and in quality of life of patients submitted to standard varicose veins stripping were maintained five years after the procedure.

Resumo em Inglês:

PURPOSE: To compare orthopedics publications from USA, Japan and China. METHODS: Scientific papers belong to ''Orthopedics'' category of Science Citation Index Expanded subject categories were retrieved from the "PubMed'' and ''Web of Knowledge'' online databases. RESULTS: In the field of orthopedics, the annual number increased significantly from 2000 to 2012 in the three countries (p<0.001). The share of articles increased significantly in China, but decreased significantly in Japan and USA (p<0.05). In 2012, USA contributed 35.3% of the total world output in orthopedics field and ranked 1st; Japan contributed 5.9% and ranked 4th; China contributed 5.2% and ranked 5th. Publications from USA had the highest accumulated IFs and the highest total citations of articles (USA > Japan > China, p<0.001). Average IF from USA was much higher than Japan and China (p<0.001). USA published the most articles in the top ten orthopedics journals (USA (14355) > Japan (1702) > China (487), p<0.01). CONCLUSION: Although China has undergone significant increase in annual number and percentage of scientific publication in orthopedics journals, it still lags far behind USA and Japan in the field of orthopedics in terms of quantity and quality.