Asymmetric XMoGeY2 (X = S, Se, Te; Y = N, P, As) monolayers as potential flexible materials for nano piezoelectric devices and nanomedical sensors.

Highly efficient nano piezoelectric devices and nanomedical sensors are in great demand for high-performance piezoelectric materials. In this work, we propose new asymmetric XMoGeY2 (X = S, Se, Te; Y = N, P, As) monolayers with excellent piezoelectric properties, dynamic stability and flexible elastic properties. The piezoelectric coefficients (d11) of XMoGeY2 monolayers range from 2.92 to 8.19 pm V-1. Among them, TeMoGeAs2 exhibits the highest piezoelectric coefficient (d11 = 8.19 pm V-1), which is 2.2 times higher than that of common 2D piezoelectric materials such as 2H-MoS2 (d11 = 3.73 pm V-1). Furthermore, all XMoGeY2 monolayers demonstrate flexible elastic properties ranging from 96.23 to 253.70 N m-1. Notably, TeMoGeAs2 has a Young's modulus of 96.23 N m-1, which is only one-third of that of graphene (336 N m-1). The significant piezoelectric coefficients of XMoGeY2 monolayers can be attributed to their asymmetric structures and flexible elastic properties. This study provides valuable insights into the potential applications of XMoGeY2 monolayers in nano piezoelectric devices and nanomedical sensors.

Activating HfX2 (X = S, Se and Te) for the hydrogen evolution reaction by introducing defects: a first-principles study.

An ideal catalyst should have a relative hydrogen adsorption Gibbs free energy (ΔGH) close to zero [J. K. Nørskov, et al., J. Electrochem. Soc., 2005, 152, J23]. However, most of the known catalysts cannot reach this standard. Based on first-principles calculations, we studied the hydrogen evolution reaction (HER) catalytic performance of pristine and defect (including vacancy and heteroatom doping) structures in terms of its ΔGH. We found that the ΔGH values of Co-doped HfS2 and P-doped HfSe2 are extremely close to zero, even closer than that of Pt (111), indicating that they are excellent catalysts. Moreover, we found that the source of the HER catalytic performance of Co-doped HfS2 is the reduction of electron accumulation of the active site S atom. Our work provides two potential ideal catalysts and provides guidance for the experimental group to search for suitable catalysts.

Silver-decorated MXene nanosheets as a radical initiator for polymerization and multifunctional hydrogels.

Silver nanoparticle-decorated multilayered titanium carbide MXene (Ag/Ti3C2Tx) itself is capable of initiating the polymerization of a variety of acrylic monomers, due to it being able to generate hydroxyl radicals via the pseudo-Fenton reaction. Furthermore, double-network hydrogel Ag/Ti3C2Tx@gelatin/PAAm is synthesized by a one-pot procedure and displays a good near-infrared light-triggered shape-memory performance.

Hsp70/Bmi1-FoxO1-SOD Signaling Pathway Contributes to the Protective Effect of Sound Conditioning against Acute Acoustic Trauma in a Rat Model.

Sound conditioning (SC) is defined as "toughening" to lower levels of sound over time, which reduces a subsequent noise-induced threshold shift. Although the protective effect of SC in mammals is generally understood, the exact mechanisms involved have not yet been elucidated. To confirm the protective effect of SC against noise exposure (NE) and the stress-related signaling pathway of its rescue, we observed target molecule changes caused by SC of low frequency prior to NE as well as histology analysis in vivo and verified the suggested mechanisms in SGNs in vitro. Further, we investigated the potential role of Hsp70 and Bmi1 in SC by targeting SOD1 and SOD2 which are regulated by the FoxO1 signaling pathway based on mitochondrial function and reactive oxygen species (ROS) levels. Finally, we sought to identify the possible molecular mechanisms associated with the beneficial effects of SC against noise-induced trauma. Data from the rat model were evaluated by western blot, immunofluorescence, and RT-PCR. The results revealed that SC upregulated Hsp70, Bmi1, FoxO1, SOD1, and SOD2 expression in spiral ganglion neurons (SGNs). Moreover, the auditory brainstem responses (ABRs) and electron microscopy revealed that SC could protect against acute acoustic trauma (AAT) based on a significant reduction of hearing impairment and visible reduction in outer hair cell loss as well as ultrastructural changes in OHCs and SGNs. Collectively, these results suggested that the contribution of Bmi1 toward decreased sensitivity to noise-induced trauma following SC was triggered by Hsp70 induction and associated with enhancement of the antioxidant system and decreased mitochondrial superoxide accumulation. This contribution of Bmi1 was achieved by direct targeting of SOD1 and SOD2, which was regulated by FoxO1. Therefore, the Hsp70/Bmi1-FoxO1-SOD signaling pathway might contribute to the protective effect of SC against AAT in a rat model.

Robust organohydrogel with flexibility and conductivity across the freezing and boiling temperatures of water.

A tough double-network (DN) organohydrogel, obtained by simply soaking a poly(2-acrylamido-2-methylpropane sulfonic acid)/polyacrylamide (PAMPS/PAAm) hydrogel in an ethylene glycol solution of lithium chloride, retains high mechanical performance, flexibility (-80 to 120 °C) and conductivity (-20 to 120 °C), paving the way towards broad applications.

A Network Meta-Analysis of Short and Long-Term Efficacy of Targeted Therapy With Single or Double-Drug Regimens in the Treatment of Stage III/IV Malignant Melanoma Based on 16 Randomized Controlled Trials.

For the treatment of stage III/IV malignant melanoma (MM), a network meta-analysis (NMA) was conducted to compare the short and long-term efficacy of targeted therapy with single or double-drug regimens. All conducted randomized controlled trials (RCTs) searched from PubMed and Cochrane Library were included in the study for direct and indirect comparison for MM. The odds ratio (OR) and surface under the cumulative ranking curves (SUCRA) value of the targeted therapy with single or double-drug regimens for treatment of stage III/IV MM were also analyzed. To group the treatments according to their similarity with regards to both outcomes, cluster analyses were performed. Ultimately, 16 RCTs were incorporated for this NMA. The NMA revealed that the overall response rate (ORR) values of single-drug regimens (Vemurafenib [Vem], Dabrafenib [Dab], and Nivolumab [Niv]) were higher than those of Dacarbazine (Dac). Also the ORR values of double-drug regimens (Dab + Trametinib [Dab + Tra], Niv + Ipilimumab [Niv + Ipi], and Vem + Cobimetinib [Vem + Cob]) were moderately higher than those of Dac. The results of the SUCRA showed that short-term efficacy of single-drug regimens (Vem and Dab) were better, while the short-term efficacy of double-drug regimens (Dab + Tra and Vem + Cob) were relatively better. It was determined that Vem, Dab, and Niv might be the best choice in evaluating the treatment of stage III/IV MM among different single-drug targeted therapy regimens, while Dab + Tra, Niv + Ipi, and Vem + Cob might have better short-term efficacy among different double-drug targeted therapy regimens. J. Cell. Biochem. 119: 640-649, 2018. © 2017 Wiley Periodicals, Inc.

[Study on decellularized laryngeal scaffold in dogs].

OBJECTIVE: To explore the survivorship and character of decellularized laryngeal scaffold in pectoralis major muscle flap in canine. METHODS: Eighteen donor larynx in experimental group were decellularized by perfusing sodium dodecyl sulphate. Three of them were used to detect the character of histology. The other fifteen ones were embedded in right pectoralis major muscle flap of acceptor canine. Donor larynx in control group were not perfused. Other experimental procedure was the same as experimental group. The specimens were harvested at two weeks, one month and two months after operation, respectively. Macroscopic view, histological examination and trypan blue staining were performed in the experimental group and control group. RESULTS: The size of the specimens decreased remarkably into disappearance in control group, there was statistical significance between the experimental group and the control group (which used least significant difference t test P < 0.05). There was only little neutrophils and lymphocytes infiltrating around the laryngeal scaffold at 2 weeks in the experimental group. One month after operation, loose connective tissue begin to form around the laryngeal scaffold. After two months of transplantation, the connective tissue became thicker and the number of blood vessels increased than before. There was a large number of lymphocytes and neutrophil infiltration around the laryngeal specimens in the control group at 2nd week. The perichondrium in the control group was damaged at one month post operation. The cartilage cells could not be detected two months after surgery. The survival rate of cartilage cell between experimental group (86.8% ± 3.2%) and the control group (88.6% ± 3.1%) did not show statistical significance before implantation (χ(2) = 0.19, P > 0.05). The survival rate of cartilage cell decreased insignificantly in experimental group while the survival rate declined obviously in the control group at two weeks and one month after operation, the difference had statistical significance (χ(2) were respectively 5.52 and 20.55, P were respectively < 0.05 and < 0.01), the survival rate of cartilage cell in experimental group was (65.8% ± 2.6%) at two months after operation, while the cartilage cell all disappeared in control group. CONCLUSIONS: Perfused decellularation technique can construct a low immunogenicity laryngeal cartilage scaffold which can survive in the chest muscle package and establish a good blood supplement. The decellularized laryngeal scaffold could be used as a biological scaffold for whole laryngeal reconstruction.

Structural integrity, ECM components and immunogenicity of decellularized laryngeal scaffold with preserved cartilage.

Decellularization techniques have been widely used as an alternative strategy for organ reconstruction. However, the compliance of tracheal or laryngeal tissues can be increased during the decellularization process, which might cause postoperative stenosis due to elimination of chondrocytes. The purpose of our study was to construct a decellularized, whole, laryngeal scaffold with preserved chondrocytes using perfusion techniques and to evaluate the immunogenicity of the decellularized scaffold in vitro and in vivo in a rat model. The cellular components and immunogenicity of the scaffold were decellularized after 14 h of perfusion with detergent and 48 h of perfusion with phosphate buffered saline. However, the cartilage was well preserved via histological analysis and a chondrocyte viability test. Compared to the fresh larynx, the decellularized larynx did not show the presence of major histocompatibility complex antigens via immunohistochemical analysis in vitro and no significant immune rejection occurred 12 weeks post-implantation. In conclusion, decellularization via perfusion can achieve a decellularized, whole-laryngeal scaffold with the cell components removed and the cartilage and extra-cellular matrix well preserved. T cell-mediated immune rejection was significantly reduced in decellularized laryngeal cartilaginous scaffolds in vivo.

A model of canine tracheal stenosis induced by radiofrequency cauterization.

OBJECTIVE: The current methods of management of tracheal stenosis have disadvantages and are controversial, therefore ideal experimental animal models for the further studies are required. The aim of this study was to establish a new model of canine tracheal stenosis by radiofrequency cauterization. METHODS: The tracheal cartilage ring was injured by radiofrequency at the level of the sixth tracheal ring in 12 mongrel dogs. A fibrolaryngoscope was used to guide the procedure. The animals were observed after operation and examined after euthanasia. Endoscopic and histological examinations were undertaken to evaluate the progress of stenosis. The degree of stenosis was calculated using the formula: degree of stenosis=(initial lumen area-final lumen area)/initial lumen area × 100%. RESULTS: Tracheal stenosis had developed in all dogs by the 21st day post operation. Costal retraction was observed in all dogs after the 18th day post operation. At the end of the study, gross and endoscopic examinations showed that stenosis had been induced to a satisfactory degree and without any complications. The median of the degree of stenosis was 92%, with a range of 84-94%. Histological examination showed that cartilage was damaged and that granulation tissue and collagen fibres had formed. CONCLUSIONS: The model of canine tracheal stenosis induced by radiofrequency cauterization is a relatively simple, reliable, and reproducible animal model. This model may be useful in the development of new methods of treatment for tracheal stenosis.

[Application of various materials in reconstruction of laryngotracheal framework].

OBJECTIVE: To investigate the effectiveness of various materials in reconstruction of laryngotracheal framework and to analyze the advantages, disadvantage, and indication of each material. METHODS: The clinical data were retrospectively analyzed, from 337 laryngotracheal stenosis patients undergoing laryngotracheal framework reconstruction with various materials between October 1986 and October 2006. There were 229 males and 108 females aged from 2 to 54 years (median, 23.5 years). According to Cotton's grading criteria for laryngotracheal stenosis, there were 94 cases of grade II, 218 cases of grade III, and 25 cases of grade IV, and all accompanied by laryngotracheal framework defect of 1-5 cm. The costal cartilage autograft was performed in 157 cases, thyroid cartilage graft in 27 cases, nasal septal cartilage graft in 8 cases, sternohyoid myocutaneous rotary door flap graft in 104 cases, hyoid bone flap of sternocleidomastoideus graft in 7 cases, musculo-periosteum flap of sternocleidomastoideus with clavicular periosteum in 21 cases, hydroxyapatite artificial tracheal ring graft in 10 cases, and pedicle myocutaneous flap with "C" shape nickel-titanic alloy net graft in 3 cases. Silastic T-tube was used after reconstruction for 6-12 months. RESULTS: Infection occurred in 5 cases and the incisions healed by second intention, the others achieved healing of incision by first intention. Intratracheal granulation formation occurred in 23 cases and choke when taking food in 6 cases; they were all cured after symptomatic treatment. After operation, 4 cases failed to be followed up and 12 cases did not recover, including 6 cases of costal cartilage autograft, 1 case of hyoid bone flap of sternocleidomastoideus graft, and 5 cases of sternohyoid myocutaneous rotary door flap graft. A total of 321 patients were followed up for 1-10 years (mean, 3.5 years). The patients had no laryngotracheal restenosis with good swallowing function and respiratory function. CONCLUSION: Different materials of laryngotracheal framework reconstruction have advantages and disadvantage respectively. The appropriate material should be selected according to the special details of pathological change, and the satisfactory curative effect may be obtained.

Reconstruction of tracheal wall defect with a mesh patch of nickel-titanium shape-memory alloy.

OBJECTIVES: We explored the feasibility of reconstructing tracheal wall defects with a mesh patch fashioned from a nickel-titanium shape-memory alloy. METHODS: A tracheal wall defect was first constructed surgically by resecting the anterior half of the tracheal wall between the second and sixth tracheal rings. The defect was reconstructed in 8 experimental animals by replacing the resected tracheal mucosa and tracheal cartilage with a pedicle skin flap, which was then enclosed in the mesh patch. In 4 control animals, only a pedicle skin flap with strap muscles was used in the reconstruction procedure. The performance of the animals was observed after surgery. At the end of the experiments, the reconstructed segment was harvested for anatomic evaluation. RESULTS: In the experimental group, 1 animal died 5 days after the operation. Endoscopic and anatomic examination of the 7 animals that survived the observation period showed that the reconstructed trachea was stable, with sufficient airway space for breathing. All 4 control animals died after the operation. After observing successful completion of this operation in animals, we successfully used this method to repair a tracheal wall defect in a human victim of a traffic accident. CONCLUSIONS: Tracheal defects can be successfully reconstructed by use of a mesh patch of nickel-titanium shape-memory alloy as an extraluminal stent--a method that avoids complications associated with intraluminal stents.

Thyroid alar cartilage graft laryngotracheal reconstruction in adults.

OBJECTIVE: To assess the outcomes of laryngotracheal reconstruction using thyroid alar cartilage grafting in adult patients with laryngotracheal stenosis. STUDY DESIGN: Case series with chart review. SETTING: Tertiary university hospital. SUBJECTS AND METHODS: Twelve adults who underwent thyroid alar cartilage graft laryngotracheal reconstruction from April 1997 to April 2009 for laryngotracheal stenosis were analyzed. The mean age of the study population was 29 years. Using the Myer-Cotton grading system, 3 patients had grade II stenosis, 7 had grade III, and 2 had grade IV. Seven of the 12 patients had subglottic stenosis, 3 had tracheal stenosis, and 2 had subglottic and upper tracheal stenosis. RESULTS: Nine of 12 (75%) patients were decannulated. Of the patients in whom laryngotracheal reconstruction failed, 2 had grade IV stenosis and 1 had severe grade III stenosis with a long segment of stenotic tissue. The postoperative complications were hematoma of the left laryngeal ventricle at the donor site in 1 patient, granulation tissues in the supraglottic and suprastomal region and at the graft site in 4 patients, and neck wound infection in 1 patient. Ossification of the thyroid alar cartilage was observed in 2 patients. A Ttube remained in situ for 6 to 18 months. CONCLUSION: Laryngotracheal reconstruction with thyroid alar cartilage graft could be a viable alternative for the treatment of laryngotracheal stenosis in adults. However, it should be used only in cases of limited and minor subglottic or tracheal stenosis.

Tissue-engineered larynx using perfusion-decellularized technique and mesenchymal stem cells in a rabbit model.

CONCLUSION: Reseeding mesenchymal stem cells (MSCs) into the decellularized laryngeal muscle matrix for construction of a tissue-engineered larynx is feasible. This in vivo maturation in the omentum could be the first step before in situ implantation of the construct. This construct could facilitate a tissue-engineered method for laryngeal reconstruction. OBJECTIVES: The extracellular matrix (ECM) and MSCs have been widely used for organ reconstruction. Our study aimed to prepare a soft tissue decellularized laryngeal scaffold with intact laryngeal cartilages utilizing a perfusion-decellularized technique, reseeding cells on it, and then construct a recellularized larynx. METHODS: Perfusion-decellularized larynges were obtained from 20 rabbits by perfusion of the common carotid arteries with detergents. Twelve perfused larynges were observed by macroscopic visualization, histological examination, scanning electron microscopy (SEM), and cartilage viability. The remaining eight perfusion constructs were reseeded with induced MSCs aspirated from eight receptor rabbits. Composites were transferred into greater omentums of receptor rabbits after adherence for 1 day in vitro. Rabbit larynges were harvested after 4 weeks and 8 weeks, respectively. Macroscopic visualization, histological examination, and immunohistochemistry were performed. RESULTS: Larynges perfused by sodium dodecyl sulfate became transparent after 2 h of perfusion. Histology and SEM indicated that the perfusion method showed a better decullularized effect. Almost no intact cells or nuclei were found, while more pores and collagen fibers were retained in the decellularized matrix. The chondrocyte vitality assay indicated that chondrocyte vitality was high. Vascularization was clearly seen by 4 weeks and relatively integrated cartilage frameworks remained by 8 weeks. Histological and immunohistochemical examinations clearly showed muscle bundles and vessels.

Experimental study on an airway prosthesis made of a new metastable ß-type titanium alloy.

OBJECTIVE: Surgical treatment of a subglottic stenosis can lead to a cricoid cartilage resection, cervical trachea resection, or both that has to be reconstructed with an artificial prosthesis. However, there is at present no standard treatment in the numerous reconstruction procedures, and many prostheses encounter inflammatory rejection and mechanical constraint problems. A porous, metastable ß-type titanium alloy prosthesis was developed to improve subglottic rehabilitation. METHODS: We have designed a porous type of airway prosthesis made of porous metastable ß-type titanium alloy. We used this prosthesis (20 mm in length) to reconstruct the cricoid cartilage and the first tracheal ring in 10 mongrel dogs and evaluated its efficacy. RESULTS: One dog died of an accident with anesthesia at 1 week, 1 dog died of pneumonia about 1 month after the operation, and 6 dogs were killed between the third and eighth months after the operation. At death, all the prostheses had become completely incorporated into the host tissue. Endoscopic examination showed no airway obstruction for a postoperative period of 3 to 8 months in 8 dogs. Granulation was observed in 4 cases, and the porous, metastable ß-type titanium alloy plate was exposed in 1 case, but these dogs were asymptomatic. Light microscopic and electron microscopic analysis showed a normal mucous membrane growth on the surface of the prosthesis and no visible granulation tissue in the reconstructed cricoid and tracheal cavity. CONCLUSIONS: This airway prosthesis provided good results in canine cricotracheal reconstruction, and this study presents the possibility of successful reconstruction of the cricoid and trachea with epithelial regeneration.

[Use of silicon T-tube in laryngotracheal reconstruction].

OBJECTIVE: To discuss the function and operative method of silicon T tube in laryngotracheal reconstruction. METHOD: Two hundred and ninety-seven patients of laryngotracheal stenosis were operated with laryngotracheal reconstruction in our department. All of patients were tracheostomy dependent before reconstruction and were placed a silicon T-tube stenting for 3 to 6 months after reconstruction. RESULT: Two hundred and eighty-nine patients (97.3%) were successfully decannulated with good airway patency and effective phonation. They were followed up from 1 to 10 years, and no recurrence was found. CONCLUSION: Silicon T-tube is an effective and safe stent for laryngotracheal reconstruction. Paying attention to some application details may avoid the complication and obtain a satisfactory effect.

[Immunological study on decellularized whole laryngeal scaffold].

OBJECTIVE: To evaluate the immunogenicity of the decellularized laryngeal scaffold. METHODS: Twelve perfused, decellularized laryngeal scaffolds were obtained from rabbits through common carotid artery perfusion with detergents. The twelve decellularized laryngeal scaffolds and the twelve fresh larynxes were then implanted in para-laryngeal muscles of rabbits and harvested after two weeks, four weeks, twelve weeks and twenty-four weeks, respectively. Macroscopic view, histological examination and lymphocyte infiltration test were performed. RESULTS: The decellularized larynxes were implanted and preserved the laryngeal extracellular matrix and laryngeal architecture. The decellularized larynx did not show obvious immunological rejection after implanted into the para-laryngeal muscles of the recipient rabbits. The volume of implanted larynx became smaller but retained cartilage scaffold. The larynxes in the control group presented the serious immunological rejection and the majority tissues of the larynxes were disintegrated and substituted by the fibrous connective tissues after four weeks. The peripheral tissues were damaged and necrotic at different degrees. The quantity of the lymphocyte infiltration in the control group was higher than that in the experiment group and the result had the statistical significance (P < 0.01). CONCLUSIONS: Perfused, decellularized technique can construct a low immune laryngeal cartilage scaffold which could be a satisfactory material for laryngeal repair.

[A preliminary study on the preparation of perfusion-decellularized laryngeal scaffold and the feasibility of laryngeal muscle reconstruction].

OBJECTIVE: To prepare a decellularized whole laryngeal scaffold by utilizing a perfusion-decellularized technique, reseed cells on it, and construct decellularized laryngeal muscles. METHODS: Perfusion decellularized larynxes were obtained by common carotid arterious perfusion with detergents. Then they were performed by macroscopic view, histological examination, scanning electron microscopy (SEM) and cartilage viability. Decellularized laryngeal scaffold were then reseeded with inducted mesenchymal stem cells (MSCs). Composites were transferred into greater omentums of rabbits after one day's adherence and harvested after eight weeks. Macroscopic view, histological examination and immunohistochemistry were performed. RESULTS: Perfusion larynxes became transparent after two hours. Histology and SEM indicated that perfusion method showed better decullularized effect. More vintages and collagen fibers but no intact cell or nuclei were retained in the decellularized matrix. Porosity measured by Image pro plus 6.0 was 80.4% +/- 3.2% (x +/- s). Chondrocyte vitality assay indicated chondrocyte vitality rate in the perfusion group was 86.9% +/- 1.5%. After eight weeks, vascularization formed and integrated cartilage frameworks still remained. Histological examination could clearly show the presence of muscle bundles and vessels. Immunohistochemical examination indicated that sarcomeric-alpha actin expressed positively in corresponding areas. CONCLUSIONS: It is feasible to reseed MSCs into the decellularized laryngeal muscle matrix for constructing tissue-engineered laryngeal muscles. This in vivo maturation into the omentum could be the first step before in situ implantation of the construct.

[Experience of diagnosis and treatment for cervical tracheoesophageal fistula complicated with laryngotracheal stenosis].

OBJECTIVE: To explore the treatment of cervical tracheoesophageal fistula (TEF) with complicated or remnant laryngotracheal stenosis (LTS) and anterior neck defect (AND). METHODS: From 1980 to 2007, 14 patients were diagnosed as TEF. Among them, 9 patients had complicated or remnant LTS, 3 patients had complicated AND, and 2 patients had TEF which were induced by Nickel-Titanium alloy mesh stent for treating benign esophageal stricture. All these patients were retrospectively studied in Tangdu Hospital. Treatment consisted of conservative therapy of TEF, staged surgical repair of TEF and laryngotracheal reconstruction according to the dimension (small or large) of TEF and complications. RESULTS: Four patients with small TEF (2 - 3 mm length) complicated LTS underwent laryngotracheal reconstruction stented with silicone T tube and TEF was adopted conservative treatment. The TEF and LTS were healed. Six patients with larger TEF (10 - 25 mm length) were repaired by staged surgical repair of TEF and laryngotracheal reconstruction. Among them, 3 cases had complicated LTS and AND, 2 cases had recent LTS and 1 case had TEF without complication. Two patients had TEF and LTS, whose TEF healed before laryngotracheal reconstruction, the remnant LTS were reconstructed and healed. During the follow-up ranged from one to ten years, 12 patients were successfully treated without complications. One patient with TEF and LTS was treated only LTS because of a segment of esophagus was closed and treated with esophagogastrostomy in the department of thoracic surgery after LTS was successfully reconstructed and cured. One patient died of bleeding and asphyxia induced by the Nickel-Titanium alloy stent because of the stent had not been taken out. CONCLUSION: The small cervical TEF complicated or remnant LTS can be treated by laryngotracheal reconstruction and conservative treatment of TEF at the same time. A larger TEF complicated LTS should be treated by staged repair of TEF and LTS.