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.

Correction: PCL NGCs integrated with urolithin-A-loaded hydrogels for nerve regeneration.

Correction for 'PCL NGCs integrated with urolithin-A-loaded hydrogels for nerve regeneration' by Xue-Han Jin et al., J. Mater. Chem. B, 2022, https://doi.org/10.1039/D2TB01624A.

PCL NGCs integrated with urolithin-A-loaded hydrogels for nerve regeneration.

Inflammation and oxidative stress are among the leading causes of poor prognosis after peripheral nerve injury (PNI). Urolithin-A (UA), an intermediate product produced by the catabolism of ellagitannins in the gastrointestinal tract, has anti-inflammatory, antioxidant, and immunomodulatory properties for inflammation, oxidative damage, and aging-related diseases. Hence, we prepared UA-loaded hydrogels and embedded them in the lumen of PCL nerve guide conduits (NGCs). The hydrogels continuously released appropriate doses of UA into the microenvironment. Based on in vitro studies, UA facilitates cell proliferation and reduces oxidative damage. Besides, the experimental evaluation revealed good biocompatibility of the materials involved. We implanted NGCs into rat models to bridge the sciatic nerve defects in an in vivo study. The sciatic functional index of the PCL/collagen/UA group was comparable to that of the autograft group. Additionally, the consequences of electrophysiological, gastrocnemius muscle and nerve histology assessment of the PCL/collagen/UA group were better than those in the PCL and PCL/collagen groups and close to those in the autograft group. In this study, UA sustained release via the PCL/collagen/UA NGC was found to be an effective alternative treatment for PNI, validating our hypothesis that UA could promote regeneration of nerve tissue.

Ti3C2Tx MXene-Coated Electrospun PCL Conduits for Enhancing Neurite Regeneration and Angiogenesis.

An electrical signal is the key basis of normal physiological function of the nerve, and the stimulation of the electric signal also plays a very special role in the repair process of nerve injury. Electric stimulation is shown to be effective in promoting axonal regeneration and myelination, thereby promoting nerve injury repair. At present, it is considered that electric conduction recovery is a key aspect of regeneration and repair of long nerve defects. Conductive neural scaffolds have attracted more and more attention due to their similar electrical properties and good biocompatibility with normal nerves. Herein, PCL and MXene-PCL nerve guidance conduits (NGCs) were prepared; their effect on nerve regeneration was evaluated in vitro and in vivo. The results show that the NGCs have good biocompatibility in vitro. Furthermore, a sciatic nerve defect model (15 mm) of SD rats was made, and then the fabricated NGCs were implanted. MXene-PCL NGCs show similar results with the autograft in the sciatic function index, electrophysiological examination, angiogenesis, and morphological nerve regeneration. It is possible that the conductive MXene-PCL NGC could transmit physiological neural electric signals, induce angiogenesis, and stimulate nerve regeneration. This paper presents a novel design of MXene-PCL NGC that could transmit self-originated electric stimulation. In the future, it can be combined with other features to promote nerve regeneration.

γδ T/Interleukin-17A Contributes to the Effect of Maresin Conjugates in Tissue Regeneration 1 on Lipopolysaccharide-Induced Cardiac Injury.

The mechanisms underlying sepsis-induced cardiomyopathy (SIC) remain poorly understood, and there are no specific therapeutics for SIC. We investigated the effects of maresin conjugates in tissue regeneration 1 (MCTR1) on SIC and explored its potential mechanisms. The experiments were conducted using an endotoxemia model induced by lipopolysaccharide (LPS). Mice were given MCTR1 intravenously 6 h after LPS stimulation. Echocardiography was performed to assess cardiac function 12 h after LPS administration. Treatment with MCTR1 significantly enhanced cardiac function and reduced LPS-induced increase of mRNA expression levels of inflammation cytokines. Transcriptomic analysis indicated that MCTR1 inhibited neutrophil chemotaxis via the IL-17 signaling pathway. We confirmed that MCTR1 reduced the expressions of neutrophil chemoattractants and neutrophil infiltration in the LPS-stimulated hearts. MCTR1 also resulted in a considerable reduction in IL-17A production mainly derived from γδ T cells. Moreover, our results provided the first evidence that neutralizing IL-17A or depletion of γδ T cells markedly decreased neutrophil recruitment and enhanced cardiac function in LPS-induced cardiac injury. These results suggest that MCTR1 alleviates neutrophil infiltration thereby improves cardiac function in LPS-induced cardiac injury via the IL-17 signaling pathway. Thus, MCTR1 represented a novel therapeutic strategy for patients with SIC.

Dexmedetomidine promotes inflammation resolving through TGF-ß1 secreted by F4/80+Ly6G+ macrophage.

Dexmedetomidine (DEX) is a highly selective α2-adrenoceptor agonist, which can regulate inflammatory responses. However, whether DEX interferes with the inflammation resolving remains unclear. Here, we reported the effects of DEX on zymosan-induced generalized inflammation in mice during resolution. Mice were administered intraperitoneally with DEX after the initiation of sepsis. The resolution interval (Ri), a vital resolution indice, decreased from twelve hours to eight hours after the administration of DEX. The induction of peritoneal pro-inflammatory interleukin [IL] - 1ß and tumour necrosis factor-α (TNF-α) appeared to be inhibited. Of interest, the anti-inflammatory transforming growth factor-ß1 (TGF-ß1) but not IL-10 levels were up-regulated at twenty-four hours in the DEX group along with 1.0 mg/mice zymosan A (ZyA) treatment. The expression levels of multiple genes related to protective immune processes and clearance functions were detected and revealed the same trends. DEX markedly increased the F4/80+Ly6G+ macrophage population. Additionally, the adequate apoptotic neutrophil clearance from injury after DEX installation could be reverse by opsonization or co-instillation of TGF-ß1 neutralizing antibody in vivo, promoting the inflammation-resolution programs. In conclusion, DEX post-treatment, via the increase of F4/80+Ly6G+ macrophages, provokes further secretion of TGF-ß1, leading to the attenuated cytokine storm and accelerated inflammation resolving.

Biomechanical analysis of the closed reduction internal fixation with cannulated screw of femoral neck fractures.

ABSTRACT: The influencing factors in closed reduction internal fixation with cannulated screw of femoral neck fractures have not been well investigated. This study evaluated these factors in patients with femoral neck fractures.Fifty-seven patients (36 males and 21 females) diagnosed with femoral neck fracture with the average age of 52.44 ±â€Š15.04 years who underwent closed reduction internal fixation with cannulated screw were included in this study. Data were collected through case report reviews, phone call follow-ups, and outpatient follow-ups to evaluate pre- and postoperative radiograph images. Statistical analysis was performed using Garden classification, binary and multinomial logistic regression analysis by including factors such as patient's age, gender, fracture type, time to fixation, reduction quality, functional recovery period, removal of cannulated screw, and preoperative traction. Logistic regression analysis revealed that age and reduction quality was statistically significant (P < .05) to clinical outcome and other factors were not statistically significant.The main factors affecting clinical outcomes were functional recovery and reduction quality. The biomechanical effects of fixation provide a good foundation for fracture healing. Patient's conditions should be carefully evaluated before selecting reduction procedures to reach an optimal surgical outcome.

Value of a smartphone-compatible thermal imaging camera in the detection of peroneal artery perforators: Comparative study with computed tomography angiography.

BACKGROUND: The aim of this study was to investigate the value of a smartphone-compatible thermal imaging camera in the mapping of the peroneal artery perforators. METHODS: Twelve consecutive patients scheduled for fibular flap reconstruction were enrolled. The lower limbs were first studied using smartphone-based dynamic infrared thermography (DIRT). During the rewarming, the hotspots were marked, small rubber markers were taped to the registered sites, and then the patients were sent for a CT scan. The diagnostic performance of smartphone-based DIRT was evaluated by comparing the DIRT findings with CT angiography and intraoperative findings. RESULTS: DIRT detected 42 of the 57 dominant perforators in 24 limbs and resulted in a sensitivity of 73.7% and a positive predictive value of 65.6%. CONCLUSIONS: The sensitivity and positive predictive value of the smartphone-based DIRT are low. Currently, it should be used as an adjunctive tool together with the established imaging techniques.

Electrospinning of PELA/PPY Fibrous Conduits: Promoting Peripheral Nerve Regeneration in Rats by Self-Originated Electrical Stimulation.

Peripheral nerve injuries represent a great challenge for surgeons. The conductive neural scaffold has experienced increasing interest because of its good biocompatibility and similar electrical properties as compared to those of a normal nerve. Herein, nerve conduits made from poly(d,l-lactide)-co-poly(ethylene glycol) and polypyrrole (20%, 30%, and 50%) (PELA-PPY) were prepared by electrospinning, and used in regeneration of peripheral nerve defects. The results of an in vitro experiment indicated a high biocompatibility for the as-prepared materials, supporting the attachment and proliferation of a rat pheochromocytoma PC-12 cell. Furthermore, the PELA-PPY nerve conduit implanted in the sciatic nerve defects (10 mm) of the Spraguee-Dawley rats for 12 weeks showed similar results with the autograft, while it demonstrated a better outcome than the PELA nerve conduit in electrophysiological examination, sciatic function index, total amount of regenerated myelinated nerve fibers, axon diameter, myelin thickness, and several immunohistochemistry indices (S-100, laminin, neurofilament, bromodeoxyuridine, and glial fibrillary acidic portein). We supposed that the bioactivity is mainly generated by the PPY in composite nanofibers which could transmit self-originated electrical stimulation between cells. Due to the facile preparation and excellent in vivo performance, the PPY-PELA nerve conduit is promising for use as a bioengineered biomaterial for peripheral nerve regeneration.

Energy Metabolism Disorder as a Contributing Factor of Rheumatoid Arthritis: A Comparative Proteomic and Metabolomic Study.

OBJECTIVES: To explore the pathogenesis of rheumatoid arthritis (RA), the different metabolites were screened in synovial fluid by metabolomics. METHODS: Synovial fluid from 25 RA patients and 10 normal subjects were analyzed by GC/TOF MS analysis so as to give a broad overview of synovial fluid metabolites. The metabolic profiles of RA patients and normal subjects were compared using multivariate statistical analysis. Different proteins were verified by qPCR and western blot. Different metabolites were verified by colorimetric assay kit in 25 inactive RA patients, 25 active RA patients and 20 normal subjects. The influence of hypoxia-inducible factor (HIF)-1α pathway on catabolism was detected by HIF-1α knockdown. RESULTS: A subset of 58 metabolites was identified, in which the concentrations of 7 metabolites related to energy metabolism were significantly different as shown by importance in the projection (VIP) (VIP ≥ 1) and Student's t-test (p<0.05). In the 7 metabolites, the concentration of glucose was decreased, and the concentration of lactic acid was increased in the synovial fluid of RA patients than normal subjects verified by colorimetric assay Kit. Receiver operator characteristic (ROC) analysis shows that the concentration of glucose and lactic acid in synovial fluid could be used as dependable biomarkers for the diagnosis of active RA, provided an AUC of 0.906 and 0.922. Sensitivity and specificity, which were determined by cut-off points, reached 84% and 96% in sensitivity and 95% and 85% in specificity, respectively. The verification of different proteins identified in our previous proteomic study shows that the enzymes of anaerobic catabolism were up-regulated (PFKP and LDHA), and the enzymes of aerobic oxidation and fatty acid oxidation were down-regulated (CS, DLST, PGD, ACSL4, ACADVL and HADHA) in RA patients. The expression of HIF-1α and the enzymes of aerobic oxidation and fatty acid oxidation were decreased and the enzymes of anaerobic catabolism were increased in FLS cells after HIF-1α knockdown. CONCLUSION: It was found that enhanced anaerobic catabolism and reduced aerobic oxidation regulated by HIF pathway are newly recognized factors contributing to the progression of RA, and low glucose and high lactic acid concentration in synovial fluid may be the potential biomarker of RA.

Septal and anterior reverse mismatch of myocardial perfusion and metabolism in patients with coronary artery disease and left bundle branch block.

The effects of left bundle branch block (LBBB) on left ventricular myocardial metabolism have not been well investigated. This study evaluated these effects in patients with coronary artery disease (CAD).Sixty-five CAD patients with complete LBBB (mean age, 61.8 ±â€Š9.7 years) and 65 without LBBB (mean age, 59.9 ±â€Š8.4 years) underwent single photon emission computed tomography, positron emission tomography, and contrast coronary angiography. The relationship between myocardial perfusion and metabolism and reverse mismatch score, and that between QRS length and reverse mismatch score and wall motion score were evaluated.The incidence of left ventricular septum and anterior wall reverse mismatching between the two groups was significantly different (P < 0.001 and P = 0.002, respectively). The incidences of normal myocardial perfusion and metabolism in the left ventricular lateral and inferior walls were also significantly different between the two groups (P < 0.001 and P < 0.001, respectively). The incidence of septal reverse mismatching in patients with mild to moderate perfusion was significantly higher among those with LBBB than among those without LBBB (P < 0.001). In CAD patients with LBBB, septal reverse mismatching was significantly more common among those with mild to moderate perfusion than among those with severe perfusion defects (P = 0.002). The correlation between the septal reverse mismatch score and QRS length was significant (P = 0.026).In patients with CAD and LBBB, septal and anterior reverse mismatching of myocardial perfusion and metabolism was frequently present; the septal reverse mismatch score negatively correlated with the QRS interval.

Up-regulation of fatty acid oxidation in the ligament as a contributing factor of ankylosing spondylitis: A comparative proteomic study.

OBJECTIVES: The present study first utilized a standardized shotgun proteomic analysis method to determine differences in protein expression of fibroblasts in the ligament between AS patients and healthy controls. METHODS: Proteins extracted from primarily cultured FLLs from 35 AS patients and 10 normal subjects were analyzed by automated 2D-Nano-LC-ESI-MS/MS. Differentially expressed proteins were screened by 2-sample t-test and fold change. Bioinformatics analysis of differentially expressed proteins was based on the IPA. Fatty acid ß-oxidation-related proteins and INSR pathway-related proteins in the ligament were confirmed by real-time PCR and Western blot. RESULTS: A total of 556 differential proteins were screened in AS. Of them, 322 proteins were up-regulated and the remaining 234 proteins were down-regulated. GO and pathway analyses showed that six fatty acid ß-oxidation-related proteins (HADHB, ECHS1, ACSL4, ACADM, ACSL1 and HADH) were up-regulated in FLL cells, which was consistent with the results obtained from real-time PCR, Western blot and MS, while INSR pathway-related proteins (INSR, IRS1, PI3K and PKC) was low in the ligament of AS as compared with that in healthy controls. CONCLUSION: The lower body fat level in AS maybe due to up-regulation of fatty acid ß-oxidation-related enzymes regulated by INSR/PI3K/PKC pathway. BIOLOGICAL SIGNIFICANCE: Ankylosing spondylitis (AS), a common spondyloarthropathy, is an inflammatory rheumatic disease with a predilection for the axial skeleton. Clinical hallmarks of AS include sacroiliitis, uveitis, enthesitis and persistent spinal inflammation. The pathogenic mechanism of disease causation and perpetuation remains poorly understood. In this study, we primarily cultured fibroblast cells from ligament biopsies, knowing that fibroblast cells are dominant cells in the diseased ligament. One of the characteristic pathologic changes in AS is inflammation of the attachment points, including the muscle, ligament and bone or joint capsule. Inflammation of the tendon attachment point is usually non-bacterial and can lead to pain and swelling of the tendon ligament. To obtain more information, we used Shotgun proteomic analysis based on multidimensional liquid chromatography tandem mass spectrometry (LC-MS/MS). we firstly mixed the lysates of FLL cells derived from the ligaments of 35 AS patients and 10 normal subjects, identified proteins by automated 2D-Nano-LC-ESI-MS/MS method, GO and pathway analyses showed that six fatty acid ß-oxidation-related proteins (HADHB, ECHS1, ACSL4, ACADM, ACSL1 and HADH) were up-regulated in the ligament, which was consistent with the results obtained from real-time PCR, Western blot and MS, while INSR pathway-related proteins (INSR, IRS1, PI3K and PKC) was low in the ligament of AS as compared with that in healthy controls. We also find that AS subjects had significantly lower body mass index (BMI) and BMI Z-scores compared with that in healthy controls. The results remind us that up-regulation of fatty acid ß-oxidation-related proteins lower the body fat content, which is a new discovery contributing to the progression of AS. This is the first report on fatty acid oxidation in AS. It was found that the body fat level was low in AS due to high fatty acid oxidation, suggesting that insulin signaling may play an important role in the metabolic switch from predominant to fatty acid metabolism that characterizes the ligament of AS. One mechanism for this transition is increased expression of genes that regulate the rate of fatty acid oxidation. This effect may be mediated by PI3K, a downstream mediator of many receptor tyrosine kinases, including the INSR. This is a newly discovered factor contributing to the progression of AS.

HSV-2 vaccine: current status and insight into factors for developing an efficient vaccine.

Herpes simplex virus type 2 (HSV-2), a globally sexually transmitted virus, and also one of the main causes of genital ulcer diseases, increases susceptibility to HIV-1. Effective vaccines to prevent HSV-2 infection are not yet available, but are currently being developed. To facilitate this process, the latest progress in development of these vaccines is reviewed in this paper. A summary of the most promising HSV-2 vaccines tested in animals in the last five years is presented, including the main factors, and new ideas for developing an effective vaccine from animal experiments and human clinical trials. Experimental results indicate that future HSV-2 vaccines may depend on a strategy that targets mucosal immunity. Furthermore, estradiol, which increases the effectiveness of vaccines, may be considered as an adjuvant. Therefore, this review is expected to provide possible strategies for development of future HSV-2 vaccines.

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.

Telangiectatic osteosarcoma: a review of literature.

Telangiectatic osteosarcoma is a rare variant of osteosarcoma and hence its occurrence, presentation, and prognosis are poorly understood. With advancements in technology and available treatment options, the scenario of its diagnosis, management, and outcome has changed. Chemotherapy with surgery was challenged previously, but has now been proved to be beneficial. We reviewed the available literature and compared results to define the characteristics of the disease, its presentation, radiographic and pathologic features, optimal treatment, and prognosis.

[Case-control study on minimally invasive percutaneous new plate osteosynthesis applied in proximal humerus fractures in elder patients].

OBJECTIVE: To evaluate the clinical significance of minimally invasive percutaneous new plate osteosynthesis (MIPPO) applied in three and four-part fractures of proximal humerus in elder patients. METHODS: From June 2008 to December 2010, 98 old patients with three and four-part fractures of proximal humerus were treated with locking plate osteosynthesis. There were 43 males and 55 females with an average age of (71.3 +/- 6.2) years ranging from 65 to 84. Among them,47 cases were treated with minimally invasive percutaneous new plate osteosynthesis (MIPPO) through antrolateral transdeoltoid approach, and meanwhile 51 cases were treated with open reduction and internal fixation (ORIF) through a traditional deltopectoral approach. The operation time,blood loss,wound complications and hospital stay were recorded. The functional outcomes of the shoulder were assessed according to Constant score. RESULTS: Ninety-six patients were followed up for 13 to 42 months (averaged 18.1 months),and 2 patients died during the follow-up period. The mean blood loss of the MIPPO group was lower than that of the ORIF group by 125 ml (P < 0.05). There was no difference in the operation time between two groups. But the MIPPO group had a slightly shorter hospital stay than the ORIF group (P < 0.05). All the fractures united clinically and radiologically. The difference of the mean healing time between two groups was not significant. The mean Constant score at final follow-up of two groups had no statistic difference. But the rate of complication of the MIPPO group was lower than that of the ORIF group (P < 0.05). Only 1 case of the MIPPO group had axillary nerve paralysis post-operatively, but 4 cases had slack internal fixation and 2 cases had avascular necrosis of the humeral head in the ORIF group. CONCLUSION: The technique of percutaneous insertion combined new locking plate internal fixation has the advantages of less blood loss, rapid recovery, less vascular damage, lower risk of complications and so on. It can effectively treat the proximal humerus three-and four-part fractures, especially to elder patients with osteoporosis.

Changes of lymph metabolites in a rat model of sepsis induced by cecal ligation and puncture.

BACKGROUND: Sepsis is a clinical syndrome defined by a systemic response to infection and remains a prevalent clinical challenge. The underlying pathophysiology of sepsis is poorly understood. Using a metabolomic method, the present study observed changes in lymph composition during sepsis in a septic model in an attempt to find out new biomarkers for the early diagnosis and treatment of sepsis. METHODS: Adult male Sprague-Dawley rats underwent cecal ligation and puncture. Blood samples were obtained via the lateral caudal vein, and lymph was obtained from the thoracic duct. Cytokines were measured in plasma and lymph samples by enzyme-linked immunosorbent assay at different time points after cecal ligation and puncture. Rat lymph samples were analyzed by high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry. Multivariate analysis was used to profile potential biomarkers in rat septic lymph samples. RESULTS: Plasma and lymph tumor necrosis factor α, interleukin 1ß, and interleukin 6 levels were elevated in septic group as compared with the control. Of the 10 characteristic metabolites identified in the septic model, six (palmitoyl-L-carnitine, creatinine, phenylalanine, isonicotinic acid, choline, and 5-azacytidine) were high, and four (1-O-Hexadecyl-2-lyso-glycero-3-phosphorylcholine, alanine, 4-amino-5-hydroxymethyl-2-methylpyrimidine, and asymmetric dimethylarginine) were low. CONCLUSION: These biomarkers were mainly involved in energy metabolism and vascular tone and may prove beneficial to distinguish sepsis from other inflammatory conditions or predict outcomes.

[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.

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.

[Responses of pancreatic cancer cells to stimulations by nerve growth factor and the role of Trk-A expression].

OBJECTIVE: To study the responses of different pancreatic cancer cells to stimulations by nerve growth factor (NGF) and explore the role of Trk-A in such responses. METHODS: Five pancreatic cancer cell lines (MIA-PaCa-2, PANC-1, SW-1990, AsPC-1, and BxPC-3) were exposed to different concentrations of NGF (0, 4, 20, 100, and 500 ng/ml). MTT and Matrigel invasion method were used to observe the changes in the cell proliferation and invasion ability. Trk-A expression in these cells was detected by PCR and Western blotting, and the relations of Trk-A expression to the cell proliferative and invasive abilities following NGF treatment were analyzed. RESULTS: NGF at 100 ng/ml most obviously stimulated the cell proliferation, and PANC-1 cells showed the highest while AsPC-1 cells showed the least sensitivity to 100 ng/ml NGF stimulation. Matrigel invasion test showed that NGF enhanced the invasiveness of PANC-1 and MIA-PaCa-2 cells but produced only limited effect on AsPC-1 cells; the effect of NGF was completely inhibited by the Trk-A inhibitor CEP701. The expression levels of Trk-A mRNA and protein were the highest in PANC-1 cells and the lowest in AsPC-1 cells. CONCLUSION: NGF can enhance the proliferation and invasiveness of pancreatic cancer cells, and this effect is possibly mediated by Trk-A protein.