In vivo performance of decellularized tracheal grafts in the reconstruction of long length tracheal defects: Experimental study.

Background: The repair of long-segment tracheal lesions remains an important challenge. Nowdays no predictable and dependable substitute has been found. Decellularized tracheal scaffolds have shown to be a promising graft for tracheal transplantation, since it is non-immunogenic.

Experimental Tracheal Replacement: Angiogenesis and Null Apoptosis Promote Stenosis.

Background: Tracheal replacement is a challenge for thoracic surgeons due to stenosis in the trachea-prosthesis anastomosis. We propose that stenosis occurs due to fibrosis as a result of an abnormal healing process, characterized by an increased expression of wound healing growth factors (vascular endothelial growth factor [VEGF], survivin, and CD31), which promote angiogenesis and decrease apoptosis. We analyzed the immunoreactivity of VEGF, survivin, CD31, and caspase-3 in the development of fibrotic stenosis in prosthetic tracheal replacement.

Fast cyclical-decellularized trachea as a natural 3D scaffold for organ engineering.

Commonly reported decellularization protocols for trachea may take up from several weeks to months in order to remove the cellular materials. Two years ago, we significantly reduced the time of decellularization trachea process using trypsin. Despite the positive outcome, the protocol was useful to produce 5 cm graft length, an unsuitable length graft for most patients with tracheal disorders.

Lung necrosectomy in pediatric patients with necrotizing pneumonia.

Introduction: Necrotizing pneumonia is the consolidation of lung parenchyma with destruction and necrosis, forming solitary or multiloculated radiolucent foci. When antibiotic treatment fails and clinical course does not improve, patients might need lung tissue resection: segmentectomy, lobectomy or bilobectomy. We have performed a more conservative surgical approach in pediatric patients with necrotizing pneumonia, lung necrosectomy: resection of unviable necrotic tissue, to preserve more healthy and potentially recoverable lung parenchyma.

Surgical Skills Training with Cryopreserved Rat Stomachs.

The objective of this study is to present a high-fidelity bench model of cryopreserved stomachs that can be used while learning surgical skills. Thirty stomachs were harvested from Wistar rats at the end of non-abdominal research studies. The stomachs were washed with cold saline solution and filled with hyaluronic acid solution.

Bench surgical training with lyophilized esophageal segments.

Purpose: To present lyophilized esophageal segments that can be used to learn surgical skills.

Methods: Four esophagus were harvested from four non-esophagus related research dogs at the moment of euthanasia. Each esophagus was trimmed in 3 cm long segments.

Canine tracheal cartilage cryopreservation: freezing injury is not related to caspase-3 expression.

Currently, there are no surgical strategies to treat tracheal lesions longer than 7 cm. Such patients are not candidates for tracheal resection or end-to-end anastomosis and are thus left with only repeated palliative procedures to relieve their respiratory insufficiency. Experimental studies using cryopreserved trachea have produced contradictory results, limiting the clinical application of this technique.

[Glutaraldehyde-preserved and lyophilized bovine pericardium as materials for medialization of the vocal folds in an animal model].

Introduction: Glutaraldehyde-preserved bovine pericardium (GBP) and lyophilized GBP (LGBP) have been used successfully in repairing several anatomical defects, but their effectiveness and safety as implants to vocal cords (VC) have not been reported.

Objective: The aim of this study was to evaluate the use of GBP and LGBP as materials for medialization thyroplasty, as well as to assess the endoscopic, macroscopic and microscopic VC changes after medialization in an experimental canine model.

Material And Methods: In 12 healthy mongrel dogs, the right VC were medialized using pericardium and the left with polytetrafluoroethylene (PTFE).

Cryopreserved tracheal segments: a new tool for bench surgical training in thoracic surgery.

Purpose: To present a new low-cost high fidelity bench model of cryopreserved trachea that can be used to learn surgical skills from medical students to cardiothoracic surgery fellows.

Methods: Ten tracheas were harvested from ten non-trachea related research dogs at the moment of euthanasia. Each trachea was trimmed in six or seven rings segments.

[Experimental model of canine oleic acid-induced acute lung injury: establishment of a working model].

Introduction: There are several experimental model of acute lung injury induced by oleic acid (OA); however, there are few studies that show how this injury develops.

Objective: This study seeks to detail the x-ray, hemodynamic, gasometrical, gravimetrical, macroscopic and microscopic alterations developed in an experimental model of canine OA-induced acute lung injury (ALI).

Material And Methods: Twelve dogs were divided in 2 study groups: Group I (n=6): Control group without ALI.

[Middle ear packing with collagen-polyvinylpyrrolidone sponge. Experimental study in guinea pigs].

Introduction: Packing material is mandatory in middle ear (ME) surgery in order to avoid inflammation, adhesions and fibrotic healing. Collagen polivynil-pirrolidone (CPVP) is a healing modulator, which reduces inflammation and fibrosis. Hence we can hypothesize that packing of the ME with CPVP sponge will lead a good ME healing.

Wound healing modulators in a tracheoplasty canine model.

Postsurgical tracheal stenosis results from fibrosis formation due to ischemia. There are healing modulators, hyaluronic acid (HA) and collagen polyvinylpyrrolidone (CPVP), which reduce collagen fibers formation. Thus we can hypothesize that the topical application of one of these modulators can diminish postsurgical tracheal scarring and stenosis.

Cryopreserved tracheal grafts: a review of the literature.

Cryopreserved tracheal grafts have been used in several experimental models of long segment replacement. The clinical application of the procedure has been limited due to the fact that contradictory results have been reported. The purpose of this article is to present a review of the literature on tracheal cryopreservation.

[Lung transplantation].

Lung transplantation (LT) has evolved to become an important alternative in the management of patients with end-stage pulmonary disease and chronic respiratory failure. The beginnings of this technique can be traced back to the experiments of Carrel and Guthrie over a hundred years ago. However, it was not until 1963 when the first clinical experience was performed by Hardy.

Usefulness of bovine pericardium as interpositional graft in the surgical repair of nasal septal perforations (experimental study).

A 2.5-cm nasal septal perforation was performed in 18 pigs and repaired as follows: group I (n = 6), septal perforation without treatment; group II (n = 6), surgical repair with interpositional graft of glutaraldehyde-preserved bovine pericardium (GPBP); group III (n = 6), surgical repair with interpositional graft of lyophilized GPBP (LGPBP). The animals were evaluated clinically and radiologically (x-ray and CT scan) 2 days before surgery, daily during the first postoperative week, and weekly during the next 6 months.

[Evaluation of the use of bovine pericardium in non-anatomical lung resections in dogs].

Unlabelled: In this study we assessed the usefulness, healing, as well as the integration to lung tissue of glutaraldehyde preserved at 0.5% bovine pericardium GPBP and lyophilized (GPBPL), after reinforced resection of lung tissue in dogs by thoracotomy or thoracoscopy.

Material And Methods: GPBP and GPBPL were prepared and used to reinforce the suture line of lung resection in 30 mongrel dogs: Group I (n = 6): The GPBP were fixed on the lung with 4-0 polypropylene by thoracotomy.