Decellularized tracheal scaffolds offer a potential solution for the repair of long-segment tracheal defects. However, complete decellularization of trachea is complicated by tracheal collapse. We created a partially decellularized tracheal scaffold (DTS) and characterized regeneration in a mouse model of tracheal transplantation. All cell populations except chondrocytes were eliminated from DTS. DTS maintained graft integrity as well as its predominant extracellular matrix (ECM) proteins. We then assessed the performance of DTS in vivo. Grafts formed a functional epithelium by study endpoint (28 days). While initial chondrocyte viability was low, this was found to improve in vivo. We then used atomic force microscopy to quantify micromechanical properties of DTS, demonstrating that orthotopic implantation and graft regeneration lead to the restoration of native tracheal rigidity. We conclude that DTS preserves the cartilage ECM, supports neo-epithelialization, endothelialization and chondrocyte viability, and can serve as a potential solution for long-segment tracheal defects.
Objectives Objective evaluation of the ergonomic risk of common otolaryngology procedures and assessment of work-related musculoskeletal pain and injury. Study Design Cross-sectional intraoperative assessment and survey. Setting Department of Otolaryngology at a tertiary children’s hospital. Subjects and Methods Sixteen otolaryngology attendings, fellows, and residents participated in a blinded study. Intraoperative ergonomics was assessed for tonsillectomies, adenoidectomies, and tympanostomy tube insertions using the Rapid Upper Limb Assessment (RULA). Follow-up surveys were sent to all participating surgeons to determine the prevalence of musculoskeletal pain and formal ergonomic training. Results Zero percent (N = 0/275) of intraoperative observations were found to have a negligible level of ergonomic risk, with 47% low risk, 37% high risk, and 16% very high risk. Tympanostomy tube insertions conferred less risk than tonsillectomy and adenoidectomy, while the use of headlamp or loupes conferred increased risk. Eighty percent of respondents reported having musculoskeletal pain and 40% reported experiencing pain while operating within the past year. The most common area of pain was the cervical spine. No surgeons reported formal ergonomic training. Conclusions Our study demonstrates an unacceptable level of ergonomic risk for common procedures in otolaryngology. Furthermore, most participants reported experiencing musculoskeletal pain despite the duration of examined procedures being relatively short. The high prevalence of work-related musculoskeletal pain and the lack of ergonomic training in our cohort highlight the need for increased awareness of ergonomics as well as the development of formal ergonomic curricula.
Objective
To provide a state-of-the-art review discussing recent achievements in tissue engineered tracheal reconstruction.
Data Sources and Review Methods
A structured PubMed search of the current literature up to and including October 2015. Representative articles that discuss the translation of tissue engineered tracheal grafts (TETG) were reviewed.
Conclusions
The integration of a biologically compatible support with autologous cells has resulted in successful regeneration of respiratory epithelium, cartilage, and vascularization with graft patency, although the optimal construct composition has yet to be defined. Segmental TETG constructs are more commonly complicated by stenosis and delayed epithelialization when compared to patch tracheoplasty.
Implications for Practice
The recent history of human TETG recipients represents revolutionary proof of principle studies in regenerative medicine. Application of TETG remains limited to a compassionate use basis; however, defining the mechanisms of cartilage formation, epithelialization, and refinement of in vivo regeneration will advance the translation of TETG from the bench to the bedside.
Objective
Recent efforts to tissue engineer long-segment tracheal grafts have been complicated by stenosis and malacia. It has been proposed that both the mechanical characteristics and cell seeding capacity of TETG scaffolds are integral to graft performance. Our aim was to design a tracheal construct that approximates the biomechanical properties of native sheep trachea and optimizes seeding with bone marrow derived mononuclear cells prior to preclinical evaluation in an ovine model.
Methods
A solution of 8% polyethylene terephthalate (PET) and 3% polyurethane (PU) was prepared at a ratio of either 8:2 or 2:8 and electrospun onto a custom stainless steel mandrel designed to match the dimensional measurements of the juvenile sheep trachea. 3D-printed porous or solid polycarbonate C-shaped rings were embedded within the scaffolds during electrospinning. The scaffolds underwent compression testing in the anterior-posterior and lateral-medial axes and the biomechanical profiles compared to that of a juvenile ovine trachea. The most biomimetic constructs then underwent vacuum seeding with ovine bone marrow derived mononuclear cells. Fluorometric DNA assay was used to quantify scaffold seeding.
Results
Both porous and solid rings approximated the biomechanics of the native ovine trachea, but the porous rings were most biomimetic. The load-displacement curve of scaffolds fabricated from a ratio of 2:8 PET:PU most closely mimicked that of native trachea in the anterior-posterior and medial-lateral axes. Solid C-ringed scaffolds had a greater cell seeding efficiency when compared to porous ringed scaffolds (Solid: 19 × 104 vs. Porous: 9.6 × 104 cells/mm3, p = 0.0098).
Conclusion
A long segment tracheal graft composed of 2:8 PET:PU with solid C-rings approximates the biomechanics of the native ovine trachea and demonstrates superior cell seeding capacity of the two prototypes tested. Further preclinical studies using this graft design in vivo would inform the rational design of an optimal TETG scaffold.
On average, in both male and female adults, PVFD is associated with conversion disorder, representing a physical manifestation of underlying psychological difficulty. There also appears to be a subset of PVFD that is not associated with psychopathology. PVFD patients with a previous psychological history are prone to more depressive and anxious symptomatology. Patients with PVFD and a history of asthma or GERD are more likely to excessively complain about physical symptoms. Overall levels of stress are not higher in PVFD patients compared to a general population. However, females report more negative stress, and both males and females may have trouble coping with the amount of stress that they do have. PVFD is more common among women, more prevalent among older individuals, and can be comorbid with asthma, GERD, and previous abuse. These results have implications for treatment- psychotherapy directed for somatoform and conversion disorders may be added to traditional speech therapy for increased efficacy.
The ideal construct for tracheal replacement remains elusive in the management of long segment airway defects. Tissue engineered tracheal grafts (TETG) have been limited by the development of graft stenosis or collapse, infection, or lack of an epithelial lining. We applied a mouse model of *
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