Polyethylene glycol crosslinked decellularized single liver lobe scaffolds with vascular endothelial growth factor promotes angiogenesis in vivo.

BACKGROUND: Improving the mechanical properties and angiogenesis of acellular scaffolds before transplantation is an important challenge facing the development of acellular liver grafts. The present study aimed to evaluate the cytotoxicity and angiogenesis of polyethylene glycol (PEG) crosslinked decellularized single liver lobe scaffolds (DLSs), and establish its suitability as a graft for long-term liver tissue engineering. METHODS: Using mercaptoacrylate produced by the Michael addition reaction, DLSs were first modified using N-succinimidyl S-acetylthioacetate (SATA), followed by cross-linking with PEG as well as vascular endothelial growth factor (VEGF). The optimal concentration of agents and time of the individual steps were identified in this procedure through biomechanical testing and morphological analysis. Subsequently, human umbilical vein endothelial cells (HUVECs) were seeded on the PEG crosslinked scaffolds to detect the proliferation and viability of cells. The scaffolds were then transplanted into the subcutaneous tissue of Sprague-Dawley rats to evaluate angiogenesis. In addition, the average number of blood vessels was evaluated in the grafts with or without PEG at days 7, 14, and 21 after implantation. RESULTS: The PEG crosslinked DLS maintained their three-dimensional structure and were more translucent after decellularization than native DLS, which presented a denser and more porous network structure. The results for Young's modulus proved that the mechanical properties of 0.5 PEG crosslinked DLS were the best and close to that of native livers. The PEG-VEGF-DLS could better promote cell proliferation and differentiation of HUVECs compared with the groups without PEG cross-linking. Importantly, the average density of blood vessels was higher in the PEG-VEGF-DLS than that in other groups at days 7, 14, and 21 after implantation in vivo. CONCLUSIONS: The PEG crosslinked DLS with VEGF could improve the biomechanical properties of native DLS, and most importantly, their lack of cytotoxicity provides a new route to promote the proliferation of cells in vitro and angiogenesis in vivo in liver tissue engineering.

Reverse facial artery flap to reconstruct the medium-sized defects in the middle facial region following cancer ablation.

This retrospective clinical study assessed the reliability of the reverse facial artery flap to reconstruct the medium-sized defects in the middle facial region following cancer ablation.Fifteen medium-sized defects were repaired with reversed facial artery flap following cancer surgery. The ages of the patients ranged from 2 to 69 years; 9 were male and 6 were female. The primary lesions included palate (5 cases), maxillary gingival (6 cases), cheek or buccal mucosa (3 case), and upper lip (1 case). The size of the skin paddle varied from 4.0 cm × 6.0 cm to 5.0 cm × 10.0 cm. Direct closure was achieved at all donor sites. Fourteen of the 15 flaps survived. No donor-site problems occurred. Two patients appeared to have temporary injury of facial nerve after operation. The follow-up period ranged from 8 to 36 months; 1 patient died as a result of local recurrence and 1 patient developed cervical recurrence.Consequently, it has been demonstrated that the reversed facial artery flap had reliable blood supply and can reliably and conveniently be used for reconstruction of the medium-sized defects, especially in the middle third of oral and maxillofacial region.

Extended supraclavicular fasciocutaneous island flap based on the transverse cervical artery for head and neck reconstruction after cancer ablation.

PURPOSE: This clinical study assessed a pedicled supraclavicular fasciocutaneous island flap (SFIF) based on the transverse cervical artery that was extended to include shoulder skin for reconstructing the head and neck. PATIENTS AND METHODS: Pedicled SFIFs extended to include the shoulder skin based on the cutaneous feeder vessels and perforator vessels in the deep fascia of the transverse cervical artery were designed for 24 patients with defects of the head and neck after cancer ablation. Preoperative 3-dimensional computed tomographic angiography was performed in all patients. The patients consisted of 15 men and 9 women ranging in age from 24 to 73 years. RESULTS: The primary lesions included squamous cell carcinoma of the tongue, buccal mucosa, floor of the mouth, oropharynx, palate, and lower gingiva. Three-dimensional computed tomographic angiography showed that the transverse cervical artery arose from the thyrocervical trunk in 13 cases and from the subclavian artery in 11 cases. The diameter of the artery ranged from 0.15 to 0.24 cm. The size of flaps ranged from 4 × 8 cm to 6 × 12 cm, and the mean length of the vascular pedicle was approximately 18.5 cm. Of the flaps, 23 survived completely, for a success rate of 95.8%. Three patients underwent radiotherapy, and the follow-up period ranged from 3 to 12 months. One patient died of local tumor recurrence, and cervical recurrences developed in 3 patients. CONCLUSION: An SFIF extended to include the shoulder skin based on the cutaneous feeder vessels and perforator vessels in the deep fascia of the transverse cervical artery is a useful, viable option for defects of the head and neck after cancer ablation.

Submental flap for reconstructing tongue defect with V-Y advancement flap for repairing submental defect.

OBJECTIVE: To assess the reliability of the facial-submental artery island flap for reconstructing tongue defects and the aesthetic benefits of using two V-Y islanded flaps for repairing the resulting submental defect. STUDY DESIGN: Case series with chart review. SETTING: Patient with tongue cancer, younger patient, cosmetic outcome. SUBJECTS AND METHODS: Thirty-three tongue defects were repaired with facial-submental artery island flaps, and the submental defects were repaired with two V-Y advancement flaps. The ages of the patients ranged from 28 to 57 years; 19 were men and 14 were women. All of the lesions were tongue squamous cell carcinoma. The size of the facial-submental artery island flap ranged from 3.5x7.0 to 5.0x8.0 cm. The size of the V-Y advancement flaps ranged from 3.0x3.0 to 4.0x4.0 cm. Direct closure was achieved at all donor sites. RESULTS: The facial-submental artery island flaps and V-Y advancement flaps survived in 93.9 percent and 97.0 percent, respectively. The patients were followed for 12 to 26 months. The functional results in terms of speech and swallowing were good, and the aesthetic outcomes using two V-Y advancement flaps to repair the submental defects were satisfactory. Two patients with extracapsular lymph node spread developed local recurrence: One is alive with disease and the other is dead. CONCLUSIONS: The facial-submental artery island flap is a simple, reliable flap that is preferred for reconstructing tongue defects. Using two V-Y advancement flaps for repairing the donor site defect improves the cosmetic outcome in the submental region.

The trapezius osteomyocutaneous island flap for reconstructing hemimandibular and oral defects following the ablation of advanced oral malignant tumours.

OBJECTIVE: This study presents an effective repair method for the hemimandibular and oral defects produced during the ablation of advanced oral malignant tumours. METHODS: Nine patients (five males and four females ranging in age from 18 to 74 years; mean age 51.3 years) with advanced oral malignant tumours were treated at our institution. Trapezius osteomyocutaneous island flaps (TOIFs) including the acromion, spine, and part of the medial scapular border were used to repair the hemimandibular and oral defects. RESULTS: No major flap failure occurred. Donor-site problems have been minimal, with limited shoulder motion in all patients. The functional results in terms of speech, swallowing, and facial contour were satisfactory. The patients were followed for 6-24 months (average 15.2 months): six of them are alive with no disease, two alive with disease; and one has died of a lung metastasis. CONCLUSION: The TOIF is large, simple, and reliable, and is preferred for reconstructing hemimandibular and oral defects.

Expression of inducible nitric oxide synthase and vascular endothelial growth factor in ameloblastoma.

The purposes of this study were to determine the correlation between the expression of inducible nitric oxide synthase (iNOS) and vascular endothelial growth factor (VEGF) in ameloblastoma and to examine the relationships of this expression to angiogenesis and the clinical and biological behaviors of the tumor. Immunohistochemical staining with streptavidin peroxidase was used to analyze iNOS and VEGF expression, and CD34 was used to evaluate microvascular density (MVD) in 35 ameloblastomas (24 primary tumors and 11 recurrences) and 5 malignant ameloblastomas. Ten odontogenic keratocysts (OKCs) served as controls. On relational analysis, positive and VEGF expression and MVD counts increased in this order: OKCs, primary ameloblastoma, recurrent ameloblastoma, and malignant ameloblastoma. Differences between the ameloblastomas and OKCs were significant (P < 0.05). Among ameloblastomas, MVD counts increased with increasing expression of iNOS and VEGF (P < 0.05), and iNOS expression and VEGF expression were positively correlated (r = 0.66, P < 0.05). Inducible nitric oxide synthase expression and VEGF expression may be closely related to the angiogenesis and invasive biological behavior of ameloblastomas.

[Effect analysis of modified radical surgery in tongue cancer at early stages].

OBJECTIVE: To evaluate the oncologic efficacy, surgical safety, postoperative beauty, and morbidity of an ideal procedure of modified radical surgery in tongue cancer at early stages. METHODS: Six patients with early stage squamous cell carcinoma of tongue underwent a procedure of modified radical surgery, in which an inconspicuous incision was used, the external jugular vein, sternocleidomastoid muscle, spino-accessory nerve, and greater auricular nerve were preserved, half of glosso and mouth floor were excised, and the defect was repaired instantly. Recurrence of glosso, mouth floor and neck, regional edema, shoulder dysfunction, auricle sensibility, oral cavity function and beautiful outlook on the face and neck were evaluated clinically. RESULTS: Compared with classic radical neck dissection, this procedure of modified radical surgery showed an inconspicuous incision and pretty appearance, minor edema on face and neck, better shoulder function, and sensation of auricular skin. No recurred to the glosso, mouth floor, and neck was found during follow-up. The patients showed better oncological safety, pretty appearance of tongue, and better oral function of speech, swallow and mastication. CONCLUSION: This ideal procedure of modified radical surgery in tongue cancer at early stages lessens or avoids destruction of face and neck, shoulder malfunction, numbness of auricular skin, and oral dysfunction of speech, swallow and mastication without impairment on the oncologic safety of the radical surgery, and improves the quality of life of the patients.

Efficacy survey of swallowing function and quality of life in response to therapeutic intervention following rehabilitation treatment in dysphagic tongue cancer patients.

PURPOSE: This quasi-experimental parallel cluster study was carried out to investigate the utility of interdisciplinary swallowing therapy exercises in improving swallowing function and quality of life (QOL) in dysphagic cancer patients following tongue resection and subsequent rehabilitation treatment. METHODS: All subjects in the experimental group underwent a structured swallowing training program. The subjects in the experimental group (n = 23) received 30 min of swallowing training each day, 6 days per week for 2 weeks. The control group (n = 23) received no training. Analysis of variance was used, and the M.D. Anderson Dysphagia Inventory (MDADI) discriminated between groups of subjects. RESULTS: Patients who underwent structured swallowing training (n = 23) showed improvement in the overall MDADI score (P < 0.01) compared with the control population. Furthermore, a separate analysis of individual domains of the MDADI (global, emotional, functional, and physical) demonstrated improved QOL. Although the mean score for tongue rehabilitation indicated that ≥50% subjects in the functional subscale were improved compared with the control population, the difference was not statistically significant (P > 0.05). CONCLUSIONS: This study used objectively timed swallowing tests, an interdisciplinary swallowing therapy protocol, and a swallowing questionnaire to evaluate the effects of swallowing training. We found that implementation of swallowing education and exercises improved dysphagia and QOL in cancer patients following tongue resection and rehabilitation. Furthermore, this study indicated that swallowing safety and dysphagia training for nursing professionals is effective.

Application of CAD/CAM-assisted technique with surgical treatment in reconstruction of the mandible.

OBJECTIVE: The purpose of this clinical study was to explore the optimal method of reconstruct mandible defects individually and immediately. STUDY DESIGN: Three-dimensional model simulation technique and vascularized fibular osteomyocutaneous flap were used to repair 15 cases of mandible defects, which were caused by ameloblastoma. A three-dimensional computed tomography (CT) images were converted to a virtual model using CAD software and the 3-dimensional (3D) simulated resin models of skeleton and fibula were used to design the osteotomies, bone segment replacement and titanium mesh shaping preoperatively. RESULTS: Fibula flaps were alive and no complication occurred. The patients were satisfied with the results both esthetically and functionally. CONCLUSIONS: This preliminarily clinical study and case demonstrated that CAD/CAM-assisted technique with surgical treatment offers an individual anatomical reconstruction of the mandible in ameloblastoma patients. The procedures guarantee intraoperatively an exact placement of the preformed mesh even for precise reconstruction of extensive mandible defects.

[Clinical study of submental artery island myocutaneous flap for reconstruction of oral and maxillofacial defects following operation].

OBJECTIVE: To evaluate the outcome and indication of the reconstruction of oral and maxillofacial postoperative defects by submental artery island myocutaneous flaps. METHODS: Sixty eight cases with the reconstruction of oral and maxillofacial defects by submental artery island myocutaneous flaps from January 2006 to May 2010 were analysed retrospectively. Primary lesions included carcinomas originating from tongue (28 cases), palate (13 cases), mouth floor (9 cases), gingiva (4 cases), buccal mucosa (6 cases), lip (3 cases), and other malignant or benign tumors (5 cases). The ages ranged from 25 to 84 years (mean 58 years); 47 males and 21 females. The sizes of skin paddle varied from a minimum of 4 cm × 4 cm to a maximum of 15 cm × 10 cm. RESULTS: Of the 68 flaps, 62 were survival, 4 had partial necrosis but healed with treatments, and 2 failed due to complete necrosis. Appearance and functions of recipient sites were satisfactory. The followed-up time was 3 - 24 months, local recurrence occurred in 5 cases and cervical lymph node metastases were found in 15 patients. CONCLUSION: Submental island flap is reliable for the reconstruction of postoperative defects in early oral cancer without regional lymph node metastasis or in benign tumor.

Reverse facial artery-submental artery deepithelialised submental island flap to reconstruct maxillary defects following cancer ablation.

OBJECTIVE: The present study assessed the reliability of the reverse facial artery-submental artery deepithelialised submental island technique to reconstruct maxillary defects. METHODS: The study included 13 patients (9 men and 4 women; 43-62 years) with maxillary defects resulting from cancer ablation. Ten patients presented with maxillary gingival squamous cell carcinoma and the remaining 3 cases were hard palate squamous cell carcinomas. The maxilla was resected and the remaining defects were classified as Class 2a. Reverse facial artery-submental artery deepithelialised submental island flaps measuring 8-10 cm in length and 4-5 cm in width were used to reconstruct the defects. RESULTS: Twelve of the 13 flaps survived. No donor-site problems or palsy of the marginal mandibular branch of the facial nerve occurred. The follow-up period ranged from 8 to 24 months, 1 patient died as a result of local tumour recurrence and 2 patients developed cervical recurrence. CONCLUSION: The reverse facial artery-submental artery deepithelialised submental island flap is safe, quick and simple to use or elevate. The flap is a reliable technique for reconstructing maxillary defects following cancer ablation.

Peripheral nerve regeneration using composite poly(lactic acid-caprolactone)/nerve growth factor conduits prepared by coaxial electrospinning.

Many neurotrophic factors have been shown to promote neurite outgrowth by improving the microenvironment that is required for nerve regeneration. However, the delivery of these bioactive agents to the nerve injury site, as well as effective and local release, remains a challenging problem. We have developed a novel composite nerve conduit comprised of poly(lactic acid-caprolactone) (P(LLA-CL)) and nerve growth factor (NGF). This was developed from core-shell structured biodegradable nanofibers, which were fabricated by coaxial electrospinning of P(LLA-CL) for the shell and bovine serum albumin (BSA) or BSA/NGF for the core. In rats, gaps of 10-mm long sciatic nerves were bridged using an autograft, an empty P(LLA-CL) conduit, a NGF injection P(LLA-CL) conduit, a P(LLA-CL)/NGF composite conduit, respectively. Regenerated nerve fibers were harvested and morphological and functional evaluation of nerve regeneration was performed at 12 weeks postsurgery. Although partial biodegradation and small cracks in the conduits were observed, the conduit outlines remained intact for 12 weeks after surgery. Based on functional and histological observations, the number and arrangement of regenerated nerve fibers, myelination, and nerve function reconstruction was similar in the P(LLA-CL)/NGF conduit group to that of the nerve autograft group (p > 0.05), but was significantly greater to the empty P(LLA-CL) and injection NGF P(LLA-CL) conduit groups (both p < 0.05). Therefore, the composite P(LLA-CL)/NGF conduit, which exhibited favorable mechanical properties and biocompatibility, could effectively promote sciatic nerve regeneration in rats.

Aesthetic and functional radical surgery in young patients with stage one or two tongue cancer: a preliminary report.

INTRODUCTION: The effect of an initial radical cure and the post-operative quality of life in young patients with stage one or two tongue cancer seems to be more important than in old patients. The aim of this study was to achieve both optimal surgical effectiveness and improved post-operative quality of life for young patients with stage one or two tongue cancer. MATERIALS AND METHODS: 7 patients under 40 years of age with T(1)-T(2)N(0)M(0) squamous cell carcinoma of tongue underwent aesthetic and functional radical surgery in which reconstruction of the defect in the oral cavity and conservation of the main functional organs in neck with good scar aesthetics in the face and neck were performed. The outcomes were assessed clinically. RESULTS: No tumour recurrence was found in the tongue, floor of mouth or neck at the end of follow-up (at least 37 months). The appearance of the tongue and oral function was retained; function in face, neck and shoulder was maintained; a satisfactory cosmetic appearance of the face and neck was achieved. CONCLUSIONS: Aesthetic and functional radical surgery could ensure radical cure and unchanged, or improved post-operative, quality of life in young patients with stage one or two tongue cancer.

Purification and characterization of gigantoxin-4, a new actinoporin from the sea anemone Stichodactyla gigantea.

A new Cytolysin, termed as Gigantoxin-4, was isolated from the sea anemone Stichodactyla gigantea and found to be highly homologous with Cytolysin-3 (HMg III) from Heteractis magnifica, RTX-A from Radianthus macrodactylus, and Sticholysin-1 (St I) and Sticholysin-2 (St II) from Stichodactyla helianthus (homology 82%, 86%, 82% and 86% respectively). Its 20 N-terminal residues were identified and the full-length cDNA sequence was obtained by reverse transcription-polymerase chain reaction (RT-PCR). Multiple sequence alignments with other Cytolysins of the actinoporin family clearly indicated that Gigantoxin-4 belongs to this protein family. SDS-PAGE electrophoresis showed that this new actinoporin had a molecular mass of about 19 kDa, and possessed a high hemolytic activity to human erythrocytes (HA(50)= 40 ng/ml), which was inhibited by pre-incubation with sphingomyelin (SM) or SM-cholesterol mixtures. Our in vivo experiments showed that Gigantoxin-4 had wide toxicity to the rat cardiovascular system and the respiratory system. A concentration of 30 µg/kg Gigantoxin-4, i.v. produced a positive inotropic effect on the rat heart although final cardiovascular failure was inevitable, and 60 µg/kg Gigantoxin-4 caused respiratory arrest rapidly resulting in rat death. HE staining indicated pathological changes in various organs and tissues after i.v. administration of Gigantoxin-4.

Reverse facial-submental artery island flap for reconstruction of oropharyngeal defects following middle and advanced-stage carcinoma ablation.

To assess the reliability of the reverse facial-submental artery island flap for reconstruction of oropharyngeal defects after resection of intermediate stage and advanced carcinomas, we studied 13 patients with stage III and IV squamous cell carcinoma (SCC) of the oropharynx. They had all had their tumours excised followed by reconstruction of the oropharyngeal defect using a facial-submental artery island flap. There was no major failure of a flap, but two minor ones. The marginal mandibular branch of the facial nerve remained intact and undamaged. All donor sites healed well and scars were well-hidden. The functional results of speech and swallowing after 10-28 months' follow-up were satisfactory. One patient developed lung metastases. The facial-submental artery island flap is a simple, reliable flap that can be used for reconstructing oropharyngeal defects after resection of medium and advanced carcinomas of the oropharynx.

Pedicled mandibular osteomuscular flap for zygomatic reconstruction through a modified Weber-Ferguson incision.

The aim of this study was to evaluate the use of a pedicled mandibular osteomuscular flap for zygoma reconstruction through a modified Weber-Ferguson incision. The study included 3 male patients and 2 female patients with an average age of 46 years. Zygomatic ameloblastoma was present in 2 cases. Vascular malformation was present in 2 cases, and chondromyxoid fibroma was present in 1 case. In all 5 patients, surgery consisted of a wide excision of the lesions with margins of at least 5 mm to ensure complete removal. The defects that were created measured between 3 x 3 and 4 x 4 cm. Primary reconstruction of the zygoma was carried out by a pedicled mandibular osteomuscular flap. No flap failures occurred. Proper aesthetics and complete functionality were obtained, and there were no donor-site problems. The patients were followed up for 12 to 24 months, with an average period of 18.6 months, and recurrence was never encountered.

[Lower trapezius myocutaneous flap for repairing defects in head and neck region].

OBJECTIVE: To evaluate the anatomy basis and clinical effects of the lower trapezius myocutaneous flap to reconstruct defects in the head and neck. METHODS: From Jan. 2000 to Jan. 2004, lower trapezius myocutaneous flaps which were used to reconstruct the defects in the head and neck after radical tumors resection in twenty four cases in Center of Craniomaxillofacial Surgery of the Second Affiliated Hospital of Sun Yat-sen University were analyzed retrospectively. Male was 14,female was 10. Ages ranged from 35 to 76 (median = 54). The causes of the defects were malignant neoplasm of the tongue (n = 10), buccal (n =4), oral floor (n = 2), parotid (n = 1 ), oropharynx (n = 2), gingiva (n = 3), maxillary sinus (n = 1), zygomatic and frontal part (n = 1). Fifteen patients were primary, nine patients were recurrent. The flaps ranged from 8 cm x 7 cm to 12 cm x 10 cm. RESULTS: Twenty one flaps survived fully and the other three had partial necrosis at the distal portion. Twenty two donor sites were closed primarily. Follow up 6 to 24 months, all flaps were good, the texture and color of the flaps were satisfying. CONCLUSIONS: Lower trapezius myocutaneous flap is a thin, pliable and simple myocutaneous with a long pediculi and wide arc of rotation, and it is preferred for reconstructing huge soft-tissues defects in the head and neck regions simultaneously.

[Silencing of survivin gene enhances chemosensitivity of human tongue cancer cell line Tca8113 to cisplatin].

OBJECTIVE: To investigate the effects of survivin short hairpin RNA (shRNA) on survivin expression, cell apoptosis, and chemosensitivity of human tongue cancer cell Tca8113 to cisplatin. METHODS: Survivin-directed shRNA plasmid vector was delivered into Tca8113 cells with lipofectamine(TM) 2000 reagent. Survivin expression was detected with the reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting. Flow cytometry was used to examine cell apoptosis, and the sensitivity to anticancer agents was evaluated by methyl thiazolyl tetrazolium (MTT) assay. RESULTS: After survivin shRNA vector transfection in Tca8113 cells, the expression of mRNA/protein declined significantly, and the apoptotic rate increased in time-dependent manner up to 37.9% at 48 hours. RNAi-mediated survivin reduction selectively inhibited growth and enhanced chemosensitivity of cisplatin but not of 5-fluorouracil. CONCLUSIONS: Survivin shRNA could inhibit the expression of survivin mRNA and it's protein and enhance the chemosensitivity of cisplatin.

[An island pectoralis major myocutaneous flap for the reconstruction of tongue and floor of mouth].

OBJECTIVE: To evaluate an island pectoralis major myocutaneous flap for immediate reconstruction of the total tongue body and the floor of the mouth after radical resection of bilateral tongue carcinoma involved. METHODS: Form October 2000 to December 2002, seven patients with bilateral tongue carcinoma were selected to treat with salvage surgery, and an island pectoralis major myocutaneous flap were applied for immediate reconstruction of total body of tongue and floor of mouth. RESULTS: Six flaps survived well. Only one flap showed a partial necrosis, with no submandibular fistula, infection, and other complications. The reconstructed tongue and floor of mouth worked well. The speaking and swallowing functions were satisfactory after 2 approximately 16 months' follow-ups. Only one patient died of lung metastasis carcinoma in 9 months after the operation. CONCLUSIONS: The island pectoralis major myocutaneous flap could be an ideal selection for the immediate reconstruction of the total tongue body and the floor of mouth.