Abstract in English:Abstract Purpose: To evaluate the actual incidence of both microlithiasis and acute cholecystitis during treatment with intravenous ceftriaxone in a new rabbit model. Methods: New Zealand rabbits were treated with intravenous ceftriaxone or saline for 21 days. Ultrasound monitoring of the gallbladder was performed every seven days until the 21st day when histopathology, immunohistochemistry for proliferating cell nuclear antigen (PCNA), pro-caspase-3 and CD68, liver enzyme biochemistry, and chromatography analysis of the bile and sediments were also performed. Results: All animals treated with ceftriaxone developed acute cholecystitis, confirmed by histopathology (P<0.05) and biliary microlithiasis, except one that exhibited sediment precipitation. In the group treated with ceftriaxone there was an increase in pro-caspase-3, gamma-glutamyl transpeptidase concentration, PCNA expression and in the number of cells positive for anti-CD68 (P<0.05). In the ceftriaxone group, the cholesterol and lecithin concentrations increased in the bile and a high concentration of ceftriaxone was found in the microlithiasis. Conclusion: Ceftriaxone administered intravenously at therapeutic doses causes a high predisposition for lithogenic bile formation and the development of acute lithiasic cholecystitis.
Abstract in English:Abstract Purpose: To evaluate the efficacy of nivolumab and comparison with dacarbazine (DTIC) on peritoneal carcinomatosis of malignant melanoma in mouse model. Methods: Mouse skin melanoma cells was injected under the capsule of the peritoneal surface in the left side of the abdomen. On postoperative day ten, mouses randomised into three groups. Group 1: Control, Group 2: HIPEC (Hyperthermic intraperitoneal chemotherapy) with DTIC and Group 3: HIPEC with Nivolumab. After the sacrification on postoperative day fifteen, peritoneum evaluated macroscopically and histopathologically by using peritoneal regression grading score (PRGS). Results: In the 15th day exploration, all animals developed extensive intraperitoneal tumor growth in Group 1. In Group 2 and Group 3 median tumor size was 0.7±0.3cm and 0.3±0.2cm respectively (p: 0.023). Peritoneal carcinomatosis index (PCI) were significantly lower in Group 3 than other groups (p: 0.019). The lowest total tumor nodules in group 3 was 4 ± 2. The PGRS score was found significantly lower in Group 3 than other groups (p: 0.03). Lymphocytic response rate was found higher in the Group 3. Conclusions: It has been found that nivolumab significantly better than DTIC on peritoneal metastases of malign melanoma in mouse models. Nivolumab treatment gives promising results with pathological evidence in the treatment of metastatic disease of malignant melanoma.
Abstract in English:Abstract Purpose: To investigate the fatty acid content of different fat sources and evaluate the effect of them on plasma and hepatic lipids and on the fatty acid profile of the brain tissue of Wistar rats. Methods: Thirty male albino Wistar rats received for 59 days, the following diets: diet added of margarine with low content of polyunsaturated fatty acids (PUFA); diet added of margarine with high content of PUFA; diet added of butter; diet added of hydrogenated vegetable fat; diet added of soybean oil. Fatty acid profile of the lipid sources, blood and hepatic lipids fractions and fatty acid profile of the brain tissue were determined. Results: Margarine consumption of provided different responses as to concentrations of blood and hepatic lipid fractions. Intake of butter and hydrogenated increased LDL-c/HDL-c ratio, being the steepest increase promoted by hydrogenated vegetable fat, which also raised LDL-c levels expressively. All fats used in the treatments reduced the cerebral concentration of docosahexaenoic acid when compared to soybean oil (control). Conclusion: The different fat sources commonly consumed by population provided different responses in vivo. This is particularly relevant considering the role of these lipids in the incidence and prevention of cardiovascular diseases.
Abstract in English:Abstract Purpose: To investigate the efficacy of allogeneic mesenchymal stem-cells and autologous mononuclear cells to promote sensorimotor recovery and tissue rescue. Methods: Female rabbits were submitted to the epidural balloon inflation method and the intravenous cells administrations were made after 8 hours or seven days after injury induction. Sensorimotor evaluation of the hindlimbs was performed, and the euthanasia was made thirty days after the treatment. Spinal cords were stained with hematoxylin and eosin. Results: Both therapies given 8 hours after the injury promoted the sensorimotor recovery after a week. Only the group treated after a week with mononuclear cells showed no significant recovery at post-injury day 14. In the days 21 and 28, all treatments promoted significant recovery. Histopathological analysis showed no difference among the experimental groups. Our results showed that both bone marrow-derived cell types promoted significant sensorimotor recovery after injury, and the treatment made at least a week after injury is efficient. Conclusion: The possibilities of therapy with bone marrow-derived cells are large, increasing the therapeutic arsenal for the treatment of spinal cord injury.
Abstract in English:Abstract Purpose: To use blood lactate (BL) as an end-point metabolic marker for the begin resuscitation of volume replacement in experimental hemorrhagic shock. Methods: Group I (n=7) was not bled (Control). Animals in Group II (n=7) were bled to a MAP of 30mmHg in thirty minutes. Hemodynamic and metabolic data were recorded at Baseline, at 30, 60 and 120 minutes after Baseline. The animals were intubated in spontaneous breathing (FIO2=0.21) with halothane. Results: Group I all survived. In Group II all died; no mortality occurred before a BL<10mM/L. Beyond the end-point all animals exhibited severe acidemia, hyperventilation and clinical signs of shock. Without treatment all animals died within 70.43±24.51 min of hypotension shortly after reaching an average level of BL 17.01±3.20mM/L. Conclusions: Swine’s breathing room air spontaneously in hemorrhagic shock not treated a blood lactate over 10mM/L results fatal. The predictable outcome of this shock model is expected to produce consistent information based on possible different metabolic and hemodynamic patterns as far as the type of fluid and the timing of resuscitation in near fatal hemorrhagic shock.
Abstract in English:Abstract Purpose: To evaluate the effect of transforming growth factor β1 (TGF-β1) on tendon-to-bone reconstruction of rotator cuff tears. Methods: Seventy-two rat supraspinatus tendons were transected and reconstructed in situ. At 8 and 16 weeks, specimens of three groups; that is control, L-dose (low dose), and H-dose (high dose) were harvested and underwent a biomechanical test to evaluate the maximum load and stiffness values. Histology sections of the tendon-to-bone interface were identified by hematoxylin-eosin or Masson trichrome stain. Collagen type III was observed by picric acid sirius red staining under polarized light. The level of insulin-like growth factor 1 (IGF-1) and vascular endothelial growth factor (VEGF) was measured by the enzyme-linked immunosorbent assay (ELISA) method. Results: Collagen type III of the H-dose group had a significant difference in histology structure compared with the L-dose group (P<0.05). The maximum load and stiffness decreased significantly in the control group compared with the values of the L-dose and H-dose groups. The stiffness among the three groups differed significantly at the same postoperative time (P<0.05). Interestingly, progressive reestablishment of collagen type III affected tendon-to-bone healing significantly in the later stages. Conclusion: The H-dose was associated with an increased collagen type III morphology stimulated by TGF-β1.
Abstract in English:Abstract Purpose: To evaluate the technical feasibility and homogeneity of drug distribution of pressurized intraperitoneal aerosol chemotherapy (PIPAC) based on a novel process of intraperitoneal drug application (multidirectional aerosolization). Methods: This was an in vivo experimental study in pigs. A single-port device was manufactured at the smallest diameter possible for multidirectional aerosolization of the chemotherapeutic drug under positive intraperitoneal pressure. Four domestic pigs were used in the study, one control animal that received multidirectional microjets of 9 mL/sec for 30 min and three animals that received multidirectional aerosolization (pig 02: 9 mL/sec for 30 min; pigs 03 and 04: 3 mL/sec for 15 min). Aerosolized silver nitrate solution was applied for anatomopathological evaluation of intraperitoneal drug distribution. Results: Injection time was able to maintain the pneumoperitoneum pressure below 20 mmHg. The rate of moderate silver nitrate staining was 45.4% for pig 01, 36.3% for pig 02, 36.3% for pig 03, and 72.7% for pig 04. Conclusions: Intra-abdominal drug distribution had a broad pattern, especially in animals exposed to the drug for 30 min. Our sample of only four animals was not large enough to demonstrate an association between aerosolization and a higher silver nitrate concentration in the stained abdominal regions.
Abstract in English:Abstract Purpose: To investigate tibial tunnel widening and knee instability after ACL reconstruction with hamstring autograft or irradiated soft tissue allograft. Methods: Eight-two patients were divided into two groups: autograft group and allograft group. Radiographic and clinical evaluations were performed. Results: Seventy patients were followed up with median of 36.3 months (range 36-38 months). Tibial tunnel widening was at or greater than 30% for nine patients in the autograft group and 15 patients in the allograft group (P = 0.0417). The average percentage of tibial tunnel widening was 26.7 ± 4.0 % and 29.7 ± 5.3 % in autograft and allograft groups, respectively (P = 0.0090). Knee range of motion was not affected by the reconstruction operation or different grafts. Thigh atrophy improved significantly within 24 months after ACL reconstructions in both groups. ACL reconstruction with the allograft leaded to less knee stability than that with the autograft from one year after operation (P = 0.0023). There was no significant difference between two groups with respect to Lysholm score (P = 0.1925) and Tegner score (P =0 .0918) at the final follow-up. Conclusion: The allograft group reported significantly more tibial tunnel widening and knee instability compared with the autograft group.
Abstract in English:Abstract Purpose: To introduce a nonliving microvascular training model based on vessels diameter and feasibility. Methods: We dissected ten oxen tongues, and divided the pedicles into three-thirds: proximal, middle and distal. We measured the external vessels diameter in all regions. We performed a descriptive statistical analysis. Three students (two beginner level and one intermediate level) performed this training. We evaluated the confidence, according Likert scale. Results: We dissected all oxen tongues, each tongue showed two parallel pedicles. Each pedicle was located at 1.5 - 2.0 cm from the midline. Proximal median artery and vein diameter were 3.9 ± 0.7, and 5.04 ± 1.44mm, respectively. In the middle third, the mean artery diameter was 3.3 ± 0.4mm, and the vein diameter was 3.5 ± 0.9mm. The distal third showed a mean artery diameter of 2.0 ± 0.42mm, and a vein diameter of 2.4 ± 0.82mm. The students performed ten anastomoses. This study showed a higher confidence level (CL) (p=0.03) than the pre training CL assessment. Conclusion: This study suggested a feasible non-animal model for microsurgical training process for beginners and intermediate trainees.