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Polyacrylonitrile pre-oxidized fiber（PANOF）is an emerging flame retardant material with low cost and high performance，showing a promising application potential as thermal protection materials in the aerospace field.Pretreated PANOF（t-PANOF）was obtained by the process of oil removing with acetone and surface modification using silane coupling agent KH570 in turn.Scanning electron microscopy（SEM），Fourier transform infrared spectroscopy（FT-IR）and X-ray photoelectron spectroscopy（XPS）were employed to figure out the changes of morphology and chemical structure of the fibers before and after pretreatment and their interfacial properties with silicone rubber（SR）.Effects of t-PANOF on the mechanical and thermal performances of SR were further investigated. With the presence of ceramic forming agent（CFA），the ablation responsive behaviors of CFA/t-PANOF/SR ternary composites were researched as well.The results show that the level of interfacial adhesion between fibers and rubber is significantly enhanced contributed from the pretreatment of PANOF，and the tensile strength of the composites is improved accordingly.However，with the increasing content of t-PANOF，the comprehensive mechanical properties of t-PANOF/SR composites show the trend that increase first and then decrease，indicating that the optimal dosage of the fibers is 5 to 10 phr.t-PANOF skeleton helps to not only enhance the dimensional stability of SR in high temperature and oxygen-rich environment，but also improve the ablation performance of CFA/t-PANOF/SR composites.The antioxidation ceramic layer with fiber skeleton as the main structure is formed on the surface of CFA/t-PANOF/SR composites under the high temperature aerobic gas with the heat flux density of 2 MW/m2，the corresponding linear and mass ablation rate are only 0.02 mm/s and 0.02 g/s respectively，which is expected to be utilized as an ablation material to satisfy the demands of the new generation of aerospace vehicles.

Objective: To investigate clinicopathological features and prognostic factors of appendiceal neuroendocrine neoplasms(a-NEN)., Methods: Clinical data of 20 patients diagnosed with a-NEN at Zhongshan Hospital of Fudan University between January 2000 and December 2016 were retrospectively analyzed. Pathological diagnosis was based on the WHO classification criteria of digestive system tumors (2010 edition). Based on the mitotic count and Ki-67 index, a-NENs were divided into grade 1 neuroendocrine tumor (NET G1), grade 2(G2) NET G2) and grade 3 (neuroendocrine carcinoma, NEC). Some special types of a-NEN (e.g. goblet cell carcinoid) and mixed adenoneuroendocrine neoplasms were classified as mixed adenoneuroendocrine carcinoma (MANEC). Follow-up was conducted by telephone or return visits. Univariate analysis was carried out using the Kaplan-Meier method, and the log-rank test was used to draw survival curves., Results: Of 20 patients, 14 were male and 6 were female with median age of 54 years. Seventeen cases presented acute right lower quadrant abdominal pain, 1 chronic right lower quadrant abdominal pain, 1 persistent abdominal discomfort with outburst whole abdominal pain and 1 was found during body check without symptoms. Twenty cases comprised 8 G1 patients, 4 G2 patients, 3 G3 patients, and 5 MANEC patients. When diagnosed, there was 1 patient with liver metastasis, 1 patient with abdominal and pelvic metastases, and 2 patients with postoperative pathological findings of lymph node metastasis. Six patients underwent appendectomy, 12 underwent right hemicolectomy, 1 underwent right hemicolectomy plus small intestine resection, and 1 underwent partial hepatectomy plus right hemicolectomy. The follow-up time was 7-187 months(average, 36 months). The total 1- and 3-year survival rates were 94.7% and 60.2%, respectively. Univariate analysis showed that age >50 years (χ 2 =7.036, P=0.008), pathology grade as MANEC (χ 2 =5.297, P=0.021), and metastasis (χ 2 =6.558, P=0.010) indicated lower 5-year survival rate., Conclusions: Most a-NEN patients have no typical symptoms, and the main complaint at consultation is acute right lower quadrant abdominal pain. Prognosis is poor for patients with age >50 years, MANEC pathology grade and metastasis.

A scaffold fabricated with lysine/nerve growth factor (NGF)/poly (lactic acid coglycolic acid) copolymer (PLGA) and acellular pigskin was evaluated in vitro as a potential artificial nerve scaffold. Properties of the scaffold such as microstructure, mechanical property, degradation behavior in PBS and water, Schwann cell adhesion property, and release of NGF were investigated. Results showed PLGA had permeated into the porous structure of acellular pigskin; its breaking strength was 8.308 MPa, breaking extensibility was 38.98%, elastic modulus was 97.27 MPa. The porosities of the scaffold ranged from 68.3% to 81.2% with densities from 0.62 g/cm3 to 0.68 g/cm3. At 4 weeks of degradation in vitro, maximum mass loss ratio was 43.3%. The release of NGF could still be detected on the 30th day, and its accumulative release rate was 38%. Lysine added into the scaffold neutralized the acidoid preventing degradation of PLGA to maintain a solution pH value. Schwann cells had grown across the scaffold after co-cultivation for 15 days. These in vitro properties of the pigskin based composite might indicate its potentiality to be an artificial nerve scaffold.