230 resultados para Vein graft
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The main aim of this study is to evaluate the capacity of human dental pulp stem cells (hDPSC), isolated from deciduous teeth, to reconstruct large-sized cranial bone defects in nonimmunosuppressed (NIS) rats. To our knowledge, these cells were not used before in similar experiments. We performed two symmetric full-thickness cranial defects (5 x 8 mm) on each parietal region of eight NIS rats. In six of them, the left side was supplied with collagen membrane only and the right side (RS) with collagen membrane and hDPSC. In two rats, the RS had collagen membrane only and nothing was added at the left side (controls). Cells were used after in vitro characterization as mesenchymal cells. Animals were euthanized at 7, 20, 30, 60, and 120 days postoperatively and cranial tissue samples were taken from the defects for histologic analysis. Analysis of the presence of human cells in the new bone was confirmed by molecular analysis. The hDPSC lineage was positive for the four mesenchymal cell markers tested and showed osteogenic, adipogenic, and myogenic in vitro differentiation. We observed bone formation 1 month after surgery in both sides, but a more mature bone was present in the RS. Human DNA was polymerase chain reaction-amplified only at the RS, indicating that this new bone had human cells. The us e of hDPSC in NIS rats did not cause any graft. rejection. Our findings suggest that hDPSC is an additional cell resource for correcting large cranial defects in rats and constitutes a promising model for reconstruction of human large cranial defects in craniofacial surgery.
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Introduction and objectives: Recurrent transplant pyelonephritis (RTP) secondary to vesico-ureteral reflux (VUR) to the transplant kidney (KTx) remains a significant cause of infectious complications with impact on patient and graft outcomes. Our objective was to verify the safety and efficacy of transurethral injection of Durasphere (R) to relieve RTP secondary to VUR after renal transplantation. Patients and methods: Between June 2004 and July 2008, eight patients with RTP (defined as two or more episodes of pyelonephritis after transplantation) and VUR to the KTx were treated with subureteral injections of Durasphere (R). The mean age at surgery was 38.8 +/- 13.8 yr (23-65). The patients were followed regularly every six months. The mean interval between the KTx and the treatment was 76 +/- 74.1 (10-238 months). The mean follow-up was 22.3 +/- 16.1 months (8-57 months). Results: Six patients (75%) were free of pyelonephritis during a mean period of follow-up of 23.2 +/- 17.1 months (8-57 months). Two of them had no VUR and four cases presented with G II VUR (pre-operative G IV three cases and one case G III). In one case, symptomatic recurrent cystitis made a second treatment necessary. This patient remained free of infections for three yr after the first treatment and for 18 months after the second treatment. Of the remaining two patients, one had six episodes of RTP before treatment in a period of three yr and only two episodes after treatment in two yr of follow-up. The last case had a new episode of pyelonephritis five months after treatment. Conclusions: Transurethral injection therapy with Durasphere (R) is a safe and effective minimally invasive treatment option for KTx patients with recurrent RTP. A second treatment seems to be necessary in some cases.
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P>Esophagocoloplasty and gastric transposition are two major methods for esophageal substitution in children with esophageal atresia, and there is broad agreement that these operations should not be performed before the children start walking. However, there are some reported advantages of performing such operations in the first months of life or in the neonatal period. In this study, we compared our experience with esophageal substitution procedures performed in walking children with esophageal atresia, with the outcomes of children who had the operation before the third month of life reported in the literature. The purpose of this study was to establish if we have to wait until the children start walking before indicating the esophageal replacement procedure. From February 1978 to October 2009, 129 children with esophageal atresia underwent esophageal replacement in our hospital (99 colonic interpositions and 30 gastric transpositions). The records of these patients were reviewed for data regarding demographics, complications (leaks, graft failures, strictures, and graft torsion), and mortality and compared with those reported in the two main articles on esophageal replacement in the neonatal period or in patients less than 3 months of age. The main complication of our casuistic was cervical anastomosis leakage, which sealed spontaneously in all except in four patients. One patient of the esophagocoloplasty group developed graft necrosis and three patients in the gastric transposition group had gastric outlet obstruction, secondary to axial torsion of the stomach placed in the retrosternal space. The long-term outcome of the patients in both groups was considered good to excellent in terms of normal weight gain, absence of dysphagia, and other gastrointestinal symptoms. The comparisons of the main complications and mortality rates in walking children with esophageal substitutions performed in the first months of life showed that the incidences of cervical anastomotic leaks and graft failures were similar, but mortality rate in the first few months of life was significantly greater than that observed in our group of patients (P = 0.001). Based on the comparison of our results with those of published series, we conclude that the recommendation of performing esophagocoloplasty or total gastric transposition in children with esophageal atresia after they start walking is still valid.
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Context Perioperative red blood cell transfusion is commonly used to address anemia, an independent risk factor for morbidity and mortality after cardiac operations; however, evidence regarding optimal blood transfusion practice in patients undergoing cardiac surgery is lacking. Objective To define whether a restrictive perioperative red blood cell transfusion strategy is as safe as a liberal strategy in patients undergoing elective cardiac surgery. Design, Setting, and Patients The Transfusion Requirements After Cardiac Surgery (TRACS) study, a prospective, randomized, controlled clinical noninferiority trial conducted between February 2009 and February 2010 in an intensive care unit at a university hospital cardiac surgery referral center in Brazil. Consecutive adult patients (n=502) who underwent cardiac surgery with cardiopulmonary bypass were eligible; analysis was by intention-to-treat. Intervention Patients were randomly assigned to a liberal strategy of blood transfusion (to maintain a hematocrit >= 30%) or to a restrictive strategy (hematocrit >= 24%). Main Outcome Measure Composite end point of 30-day all-cause mortality and severe morbidity (cardiogenic shock, acute respiratory distress syndrome, or acute renal injury requiring dialysis or hemofiltration) occurring during the hospital stay. The noninferiority margin was predefined at -8% (ie, 8% minimal clinically important increase in occurrence of the composite end point). Results Hemoglobin concentrations were maintained at a mean of 10.5 g/dL(95% confidence interval [CI], 10.4-10.6) in the liberal-strategy group and 9.1 g/dL (95% CI, 9.09.2) in the restrictive-strategy group (P<.001). A total of 198 of 253 patients (78%) in the liberal-strategy group and 118 of 249 (47%) in the restrictive-strategy group received a blood transfusion (P<.001). Occurrence of the primary end point was similar between groups (10% liberal vs 11% restrictive; between-group difference, 1% [95% CI, -6% to 4%]; P=.85). Independent of transfusion strategy, the number of transfused red blood cell units was an independent risk factor for clinical complications or death at 30 days (hazard ratio for each additional unit transfused, 1.2 [95% CI, 1.1-1.4]; P=.002). Conclusion Among patients undergoing cardiac surgery, the use of a restrictive perioperative transfusion strategy compared with a more liberal strategy resulted in noninferior rates of the combined outcome of 30-day all-cause mortality and severe morbidity. Trial Registration clinicaltrials.gov Identifier: NCT01021631 JAMA. 2010; 304(14):1559-1567 www.jama.com
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Introduction: A resorbable collagen matrix with recombinant human bone morphogenetic protein (rhBMP-2) was compared with traditional iliac crest bone graft for the closure of alveolar defects during secondary dental eruption. Methods: Sixteen patients with unilateral cleft lip and palate, aged 8 to 12 years, were selected and randomly assigned to group 1 (rhBMP-2) or group 2 (iliac crest bone graft). Computed tomography was performed to assess both groups preoperatively and at months 6 and 12 postoperatively. Bone height and defect volume were calculated through Osirix Dicom Viewer (Pixmeo, Apple Inc.). Overall morbidity was recorded. Results: Preoperative and follow-up examinations revealed progressive alveolar bone union in all patients. For group 1, final completion of the defect with a 65.0% mean bone height was detected 12 months postoperatively. For group 2, final completion of the defect with an 83.8% mean bone height was detected 6 months postoperatively. Dental eruption routinely occurred in both groups. Clinical complications included significant swelling in three group 1 patients (37.5%) and significant donor-site pain in seven group 2 patients (87.5%). Conclusions: For this select group of patients with immature skeleton, rhBMP-2 therapy resulted in satisfactory bone healing and reduced morbidity compared with traditional iliac crest bone grafting.
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Objective: To describe bypass to perigeniculate vessels for limb salvage. Design: Retrospective cohort study. Material and methods: Between 1995 and 2009, 47 bypass procedures to perigeniculate collateral arteries were performed in 46 patients (15 women, 31 men; median age, 68 years). All patients presented with critical ischaemia (tissue loss in 87.5%, rest pain in 12.5%). Mean ankle brachial index was 0.27 +/- 0.17. The site of distal anastomosis was the descending genicular artery (DGA) in 23 bypasses (1 bilateral) and the medial sural artery (MSA) in 24. Proximal anastomosis was to the external iliac artery in 2 cases, common femoral artery in 23 cases, superficial femoral artery in 8 cases, deep femoral artery in 8 cases, above-knee poplitaeal artery in 2 cases, and previous graft in 4 cases. Results: There were four deaths during the immediate postoperative period. Mean follow-up duration was 27 months. Ten patients required major amputation. Mean ankle brachial index post-operatively was 0.60 +/- 0.21. At 3 years, primary patency was 74.7 +/- 7%, secondary patency was 83.4 +/- 8%, and the limb salvage and survival rates were 73.5 +/- 7% and 77.4 +/- 7%, respectively. Conclusion: Bypass to perigeniculate arteries is a viable treatment option for critical limb ischaemia in selected patients. (C) 2011 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.
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Hepatectomy may prolong the survival of colorectal cancer patients with liver metastases. Two-stage liver surgery is a valid option for the treatment of bilobar colorectal liver metastasis. This video demonstrates technical aspects of a two-stage pure laparoscopic hepatectomy for bilateral liver metastasis. To the authors` knowledge, this is the first description of a two-stage laparoscopic liver resection in the English literature. A 54-year-old man with right colon cancer and synchronous bilobar colorectal liver metastasis underwent laparoscopic right colon resection followed by oxaliplatin-based chemotherapy. The patient then was referred for surgical treatment of liver metastasis. Liver volumetry showed a small left liver remnant. Surgical planning was for a totally laparoscopic two-stage liver resection. The first stage involved laparoscopic resection of segment 3 and ligature of the right portal vein. The postoperative pathology showed high-grade liver steatosis. After 4 weeks, the left liver had regenerated, and volumetry of left liver was 43%. The second stage involved laparoscopic right hepatectomy using the intrahepatic Glissonian approach. Intrahepatic access to the main right Glissonian pedicle was achieved with two small incisions, and an endoscopic vascular stapling device was inserted between these incisions and fired. The line of liver transection was marked following the ischemic area. Liver transection was accomplished with the Harmonic scalpel and an endoscopic stapling device. The specimen was extracted through a suprapubic incision. The falciform ligament was fixed to maintain the left liver in its original anatomic position, avoiding hepatic vein kinking and outflow syndrome. The operative time was 90 min for stage 1 and 240 min for stage 2 of the procedure. The recoveries after the first and second operations were uneventful, and the patient was discharged on postoperative days 2 and 7, respectively. Two-stage liver resections can be performed safely using laparoscopy. The intrahepatic Glissonian approach is a useful tool for pedicle control of the right liver, especially after previous dissection of the hilar plate.
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Introduction. Chronic allograft vasculopathy is an important cause of graft loss. Considering the inflammatory response in the development of chronic vascular lesions, therapeutic approaches to target the inflammatory process may be useful. We sought to investigate the possible protective effects on balloon catheter-induced vascular injury of thalidomide and tamoxifen, 2 drugs with powerful anti-inflammatory, immunomodulatory, and antifibrotic effects, using an animal model that mimics the morphologic features of chronic allograft vasculopathy. Methods. Male Wistar rats subjected to balloon catheter carotid injury (INJ) were treated with thalidomide (100 mg/kg), or tamoxifen (10 mg/kg), or vehicle. Contralateral right carotid arteries were used as uninjured controls. Morphometric and immunohistochemical analyses were performed at 14 days postinjury. Results. Injured carotid arteries showed marked neointimal hyperplasia, which was significantly inhibited among animals treated with thalidomide or tamoxifen: neointimal/media ratios of 1.4 +/- 0.4 versus 0.2 +/- 0.1 versus 0.4 +/- 0.2, for INJ, INJ + Thalid, and INJ + Tamox; respectively (P < .001). The endothelial cell loss was significantly less pronounced among animals subjected to carotid balloon injury that were treated with thalidomide (24 +/- 14 vs 1 +/- 1 cells per section in INJ, respectively (P < .05). Therapy with either thalidomide or tamoxifen effectively maintained alpha-smooth muscle actin expression in the media, similar to uninjured arteries. In this setting, tamoxifen was additionally effective to prevent the migration of myofibroblasts in to the intima. Conclusion. Thalidomide and tamoxifen were effective to reduce neointimal hyperplasia secondary to vascular damage. The vasculoprotective effects of thalidomide were more pronounced to preserve endothelial cells, whereas tamoxifen inhibited smooth muscle cell migration and proliferation. A possible beneficial effect of combined therapy with thalidomide plus tamoxifen should be addressed in future studies.
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Absence of half-nose is an extremely rare congenital malformation, which has a devastating impact on the patient and the family. A review of indexed English-language literature found 91 cases of half-nose, including 50 patients with proboscis lateralis. Pathogenesis is not clear, and the reported cases have sporadically occurred. Many aspects must be considered when reconstructing a congenital half-nose, such as timing of surgery, type of tissue to be used and the need to reconstruct nasal airway. The aim of this article is to present personal experience in seven cases of half-nose reconstruction, in order to review the literature regarding to this rare entity, highlighting aspects of incidence, pathogenesis and surgical treatment. Nasal reconstruction was performed at ages of 5-7 years to minimise psychological trauma. Forehead skin demonstrated to be an excellent donor site to re-surface the nose. For the inner lining, contralateral cutaneous nasal flap was our preference. Concerning the nasal framework reconstruction, alar contour was restored using a cartilage graft from the lower portion of ear tragus and concha. (C) 2008 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.
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Purpose: Hepatectomy remains a complex operation even in experienced hands. The objective of the present study was to describe our experience in liver resections, in the light of liver transplantation, emphasizing the indications for surgery, surgical techniques, complications, and results. Methods: The medical records of 53 children who underwent liver resection for primary or metastatic hepatic tumors were reviewed. Ultrasonography, computed tomographic (CT) scan, and needle biopsy were the initial methods used to diagnose malignant tumors. After neoadjuvant chemotherapy, tumor resectability was evaluated by another CT scan. Surgery was performed by surgeons competent in liver transplantation. As in liver living donor operation, vascular anomalies were investigated. The main arterial anomalies found were the right hepatic artery emerging from the superior mesenteric artery and left hepatic artery from left gastric artery. Hilar structures were dissected very close to liver parenchyma. The hepatic artery and portal vein were dissected and ligated near their entrance to the liver parenchyma to avoid damaging the hilar vessels of the other lobe. During dissection of the suprahepatic veins, the venous infusion was decreased to reduce central venous pressure and potential bleeding from hepatic veins and the vena cava. Results: Fifty-three children with hepatic tumors underwent surgical treatment, 47 patients underwent liver resections, and in 6 cases, liver transplantation was performed because the tumor was considered unresectable. There were 31 cases of hepatoblastoma, with a 9.6% mortality rate. Ten children presented with other malignant tumors-3 undifferentiated sarcomas, 2 hepatocellular carcinomas, 2 fibrolamellar hepatocellular carcinomas, a rhabdomyosarcoma, an immature ovarian teratoma, and a single neuroblastoma. These cases had a 50% mortality rate. Six children had benign tumors-4 mesenchymal hamartoma, 1 focal nodular hyperplasia, and a mucinous cystadenoma. All of these children had a favorable outcome. Hepatic resections included 22 right lobectomies, 9 right trisegmentectomies, 8 left lobectomies, 5 left trisegmentectomies, 2 left segmentectomies, and 1 case of monosegment (segment IV) resection. The overall mortality rate was 14.9%, and all deaths were related to recurrence of malignant disease. The mortality rate of hepatoblastoma patients was less than other malignant tumors (P = .04). Conclusion: The resection of hepatic tumors in children requires expertise in pediatric surgical practice, and many lessons learned from liver transplantation can be applied to hepatectomies. The present series showed no mortality directly related to the surgery and a low complication rate. (C) 2009 Elsevier Inc. All rights reserved.
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Thirty-one patients with unilateral long-standing facial palsy underwent I-stage reanimation with free gracilis muscle transplant innervated by the masseteric branch of the trigeminal nerve. They were divided into 2 nonrandomized groups according to insertion technique: group 1 (9 patients), interrupted suture between the free flap and the orbicularis oris of the upper and lower lip on the paralyzed side; group It (22 patients), palmaris longus tendon graft placed between the gracilis free flap and the orbicularis oris of the upper and lower lip on the nonparalyzed side. Qualitative evaluation of the smile demonstrated better results in patients from group II. Comparing the position Of the Cupid`s bow at rest, pre- and postoperatively in each patient, we observed significant improvement of facial symmetry in both groups. During smile, however, there was a significantly higher rate of centralization of the Cupid`s bow in patients submitted to reanimation with the use of the palmaris longus tendon (group II).
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AVFs may be considered the best type of venous access for chronic hemodialysis in pediatric patients with more than 20 kg who are not likely to receive a kidney transplant or be transitioned to peritoneal dialysis within one yr. The aim of the study was to report the experience in the creation of AVFs in pediatric candidates for renal transplantation using microsurgical vascular techniques, with emphasis on the details of the surgical technique. Forty children underwent 50 fistula creations - 31 radial-cephalic, 11 brachial-cephalic, five brachial-basilic and three saphenous-femoral. The vein was anastomosed to the artery in an end-to-lateral fashion by using two separate 8/0 prolene running sutures. The overall patency rate was 76.0%:22 (70.9%) of the radial-cephalic fistulas, nine (81.8%) of the brachial-cephalic, five (100.0%) of the brachial-basilic and two (66.6%) of the saphenous-femoral. There was no significant difference in patency rates between the brachial-cephalic, brachial-basilic and radial-cephalic fistulas. The incidences of fistula patency were not different for patients weighing < 20 kg compared with patients weighing > 20 kg. AVF remains as a satisfactory method for providing hemodialysis in children. The utilization of microsurgical techniques with some technical refinements described herein permits the achievement of high fistula patency rates.
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Background: Although the role of cartilage grafts in reconstruction of the posterior eyelid lamella is well established, spontaneous conjunctival epithelialization on such grafts has yet to be fully proven. The aim of this study was to perform a comparative analysis of the influence of perichondrium on conjunctival epithelialization over conchal cartilage grafts used in eyelid reconstruction in rabbits. Methods: The posterior lamellae of 100 lower eyelids from 50 rabbits were reconstructed with autogenous grafts of conchal ear cartilage. In the right eyelids, cartilage was grafted with the perichondrium in direct contact with the eyeball, and the left eyelids were reconstructed in a similar manner but using cartilage grafts without perichondrium. The animals were killed after 1, 2, 3, 4, and 5 weeks, and their lower eyelids were analyzed macroscopically and histologically. Results: The percentage difference in conjunctival epithelialization on the cartilage with perichondrium and that without perichondrium was 11.41 percent in the first week of the experiment, 13.64 percent in the second week, 18.69 percent in the third week, 10.38 percent in the fourth week, and 6.17 percent in the fifth week. The average percentage conjunctival epithelialization in the eyelids reconstructed with a cartilage graft with perichondrium was significantly higher throughout the 5 weeks of the experiment than in the eyelids reconstructed with cartilage without perichondrium (p < 0.0002). Conclusion: It was found that the perichondrium had an important role in conjunctival epithelialization in eyelids reconstructed with a cartilage graft in the present study. (Plast. Reconstr. Surg. 123: 55, 2009.)
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Objective. There are no data to support the suggestion that samples removed from one segment of the transplanted kidney are representative of the whole graft. The aim of this study was to compare the histological differences between biopsies obtained from different portions of the renal allograft and their impact on treatment recommendations. Patients and Methods. Two hundred percutaneous biopsies were performed on kidney allografts and samples were collected from the upper and lower poles (100 kidneys). All samples were randomized and blindly reviewed. We obtained the discordance rates between the poles for the grading of acute rejection and for the diagnosis of nephrotoxicity due to immunosuppression. We also checked if the differences found were sufficient to call for different clinical recommendations. These values were compared with the intrapathologist variation rates. Results. In 70 kidneys adequate sampling was obtained from both poles. The diagnosis of acute rejection were made in 1.7. The discordance rate between the upper and lower poles was 82.3% (kappa = 0.34), higher than the intrapathologist variation (P =.002). Nephrotoxicity was found in 14 kidneys. The discordance rate between the upper and lower poles was 28.6% (kappa = 0.88), with no difference compared with the intrapathologist variation. In 14 of the 70 kidneys (25.7%), discordances between poles had impact on clinical recommendations, most of these cases due to different gradings of acute rejection (78%). This number was higher than the intrapathologist variation (P =.04). Conclusions. The histopathological changes in the kidney allograft are not always homogeneous. This heterogeneity may affect the therapeutic recommendations.
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Indoleamine 2,3-dioxygenase (IDO), an enzyme that plays a critical role in fetomaternal tolerance, exerts immunoregulatory functions suppressing T-cell responses. The aims of this study were to promote IDO expression in rat islets using a nonviral gene transfer approach, and to analyze the effect of the in vivo induction of IDO in a model of allogeneic islet transplantation. The IDO cDNA was isolated from rat placenta, subcloned into a plasmid and transfected into rat islets using Lipofectamine. The efficiency of transfection was confirmed by qRT-PCR and functional analysis. The in vivo effect of IDO expression was analyzed in streptozotocin-induced diabetic Lewis rats transplanted with allogeneic islets under the renal capsule. Transplantation of IDO-allogeneic islets reversed diabetes and maintained metabolic control, in contrast to transplantation of allogeneic nontransfected islets, which failed shortly after transplantation in all animals. Graft survival of allograft islets transfected with IDO transplanted without any immunosuppression was superior to that observed in diabetic rats receiving nontransfected islets. These data demonstrated that IDO expression induced in islets by lipofection improved metabolic control of streptozotocin-diabetic rats and prolonged allograft survival.