Epithelial cells/progenitor cells in developing human lower respiratory tract: Characterization and transplantation to rat model of pulmonary injury.

Introduction: For cell-based therapies of lung injury, several cell sources have been extensively studied. However, the potential of human fetal respiratory cells has not been systematically explored for this purpose. Here, we hypothesize that these cells could be one of the top sources and hence, we extensively updated the definition of their phenotype. Methods: Human fetal lower respiratory tissues from pseudoglandular and canalicular stages and their isolated epithelial cells were evaluated by immunostaining, electron microscopy, flow cytometry, organoid assay, and gene expression studies. The regenerative potential of the isolated cells has been evaluated in a rat model of bleomycin-induced pulmonary injury by tracheal instillation on days 0 and 14 after injury and harvest of the lungs on day 28. Results: We determined the relative and temporal, and spatial pattern of expression of markers of basal (KRT5, KRT14, TRP63), non-basal (AQP3 and pro-SFTPC), and early progenitor (NKX2.1, SOX2, SOX9) cells. Also, we showed the potential of respiratory-derived cells to contribute to in vitro formation of alveolar and airway-like structures in organoids. Cell therapy decreased fibrosis formation in rat lungs and improved the alveolar structures. It also upregulated the expression of IL-10 (up to 17.22 folds) and surfactant protein C (up to 2.71 folds) and downregulated the expression of TGF-ß (up to 5.89 folds) and AQP5 (up to 3.28 folds). Conclusion: We provide substantial evidence that human fetal respiratory tract cells can improve the regenerative process after lung injury. Also, our extensive characterization provides an updated phenotypic profile of these cells.

Design and fabrication of polycaprolactone/gelatin composite scaffolds for diaphragmatic muscle reconstruction.

Diaphragmatic wall defects caused by congenital disorders or disease remain a major challenge for physicians worldwide. Polymeric patches have been extensively explored within research laboratories and the clinic for soft tissue and diaphragm reconstruction. However, patch usage may be associated with allergic reaction, infection, granulation, and recurrence of the hernia. In this study, we designed and fabricated a porous scaffold using a combination of 3D printing and freeze-drying techniques. A 3D printed polycaprolactone (PCL) mesh was used to reinforcegelatin scaffolds, representing an advantage over previously reported examples since it provides mechanical strength and flexibility. In vitro studies showed that adherent cells were anchorage-dependent and grew as a monolayer attached to the scaffolds. Microscopic observations indicated better cell attachments for the scaffolds with higher gelatin content as compared with the PCL control samples. Tensile testing demonstrated the mechanical strength of samples was significantly greater than adult diaphragm tissue. The biocompatibility of the specimens was investigated in vivo using a subcutaneous implantation method in Bagg albino adult mice for 20 days, with the results indicating superior cellular behavior and attachment on scaffolds containing gelatin in comparison to pure PCL scaffolds, suggesting that the porous PCL/gelatin scaffolds have potential as biodegradable and flexible constructs for diaphragm reconstruction.

Partial replacement of left hemidiaphragm in dogs by either cryopreserved or decellularized heterograft patch.

OBJECTIVES: Large diaphragmatic defects are still a challenging issue for reconstruction using either synthetic prosthesis or bioprosthesis. To evaluate the possibility of using diaphragm allograft as a natural bioprosthesis in humans, we conducted a two-group study and compared cryopreserved and decellularized diaphragmatic heterograft patched in a canine model. METHODS: At the end of organ harvesting from a human donor, the left hemidiaphragm was taken to the laboratory in phosphate-buffered saline solution. The next step was freezing the grafts at -80°C, and preserving them for up to 2 months in Group 1. It was subjected to a detergent-enzymatic method (containing sodium deoxycholate/DNase lavations) of decellularization for 25 cycles in Group 2. Through left thoracotomy in the eighth intercostal space, cryopreserved patches in six dogs and decellularized patches in five dogs replaced the diaphragm. During the follow-up, sonography was done in all animals, but three and two dogs in Group 1 and 2 underwent computed tomography (CT) scan, respectively. The animals were euthanized after 6 months. RESULTS: There was no mortality. Sonography showed only motion impairment of the patches in all cases. In Group 1, CT scan showed mild atelectasis and scattered infiltration in the left lower lobe, fibrotic bands and minimal fluid collection under the diaphragm. In Group 2, CT scan showed scattered fibrotic bands and mild to moderate elevation of the left hemidiaphragm. There was no evidence of gross disruption and complete healing of the suture line. Necropsy in both groups showed patches were completely replaced with a dense fibrous tissue. In Group 1, focal calcification was noticeable in every case and foreign body-type granulomas were clearly seen all over the grafted tissue. Histology in Group 2 animals showed less inflammatory cell infiltration and scattered foreign body granulomas in comparison with the cryopreserved patch graft. CONCLUSIONS: The gross healing process in the decellularized heterograft is similar to the cryopreserved diaphragm but with fewer inflammatory cells and foreign body granulomas on histology. Both of them can be used instead of bioprostheses with regard to the fact that the decellularized patch technique is more complex and expensive. It is recommended to compare them with commercial bioprostheses.

Successful airway management in a patient with tracheal stenosis and tracheoesophageal fistula: a case report.

A twenty-year-old girl was referred with tracheal stenosis (TS) which was a consequence of prolonged intubation after head injury because of previous car accident. The patient was aphasic and had normal respiration. Fiberoptic bronchoscopy showed complete tracheal obstruction at second tracheal ring level. Distal trachea was normal through tracheostomy tube. Removal of the tracheostomy tube and blind reinsertion with a new one was complicated with hypoxia and respiratory distress. Fibrotic bronchoscopy revealed large tracheoesophageal fistula (TEF) below tracheal obstruction. Reinsertion of the tracheostomy tube by fiber optic bronchoscope was successful. Multidetector CT scan was performed on the same day with confirmation of TS combined with TEF. Surgery was performed on the next day. No clinical evidence of TEF was found in back history. Inadequate evaluation of the whole length of the trachea during the first bronchoscopy was the reasons for missing TEF. TEF should be considered in patients with TS in spite of no typical symptom such as food aspiration or pulmonary infections.

Outcome of kidney transplantation in patients with polycystic kidney disease: a single center study.

Autosomal dominant polycystic kidney disease (ADPKD) is a common cause of end-stage renal disease and a common indication for renal transplantation. Patients with ADPKD show some differences in graft outcome and complications following renal transplantation. This study was undertaken to evaluate the demographics, outcome and complications of renal transplantation in patients with ADPKD. In a retrospective case-control design, 51 patients with ADPKD were recognized amongst a total of 1200 renal transplant patients. For each case, a matched control based on sex, age (+/- 5 years) and type of kidney donor, was selected. All relevant data were gathered using patients' records and PNOT software. There were 34 males (66.7%) and 17 females (33.3%) with ADPKD. Mean age at transplantation was 42.6 +/- 14.3 years and source of donor organ was predominantly live unrelated (72.5%). Forty patients (78.4%) had extra-renal manifestations of ADPKD, the most common of which were cardiac valvular disease (24 cases, 47.1%), and liver cysts (10 cases, 19.6%). Rejection occurred in 12 patients in the case-group (23.5%) in comparison to nine patients (17.6%) in the control group (p > 0.05). Twenty-nine cases (56.9%) did not develop any complications. The common complications noted after transplantation included infections (15.7% in cases vs 19.6% in controls), and cerebrovascular accidents (13.7% in cases vs 16.6% in controls). Patient outcome after short- and long-term follow-up was slightly better in the ADPKD population than the control group; however, it was not statistically significant. Also, no complication was found to occur more frequently in ADPKD patients.

Determination of the incidence and severity of hoarseness after cardiac surgery.

BACKGROUND: The aim of the study was to determine the incidence and severity of hoarseness and vocal cord dysfunction in 200 patients undergoing open heart surgery in Shiraz-Iran. MATERIAL/METHODS: This study involved prospective evaluation of 200 patients who underwent open heart surgery during the year 2003 in Shiraz University hospitals. All patients received the same standard anesthetic technique. In post-operative course, all patients were electively ventilated for variable periods depending on several factors, at least until the morning after surgery. All patients underwent direct laryngoscopy immediately after extubation by the otolaryngologist, and the existence and grade of hoarseness was evaluated on a four-point scale 6 and 12 hours after extubation. RESULTS: Two hundred patients, 64.5% male and 35.5% female, with a mean age of 56.7 (S.D. = 5.2) were evaluated. CABG was performed most frequently and the mean duration of cold perfusion was 122 minutes (S.D. = 15). CVP insertion, endotracheal intubation, sternotomy, and hypothermia were performed in all patients. Hoarseness was found to be present in 17% of patients; all but one were rated to be grade one on the four-point scale. However, laryngoscopy did not reveal anything specific. CONCLUSIONS: The incidence of hoarseness in this study was 17%; similar series reported as high as 32%. Vocal cord dysfunction never occurred in our study and hoarseness probably resulted from intubation trauma. Although we found no case of nerve injury and cord dysfunction, vocal cord palsy as a rare cause of respiratory insufficiency in chest and neck surgeries must never be overlooked.