Preparation of novel biodegradable pHEMA hydrogel for a tissue engineering scaffold by microwave-assisted polymerization.

OBJECTIVE: To prepare a novel biodegradable poly(2-hydroxyethylmethacrilate) (pHEMA) hydrogel as tissue engineering scaffold. METHODS: The pHEMA hydrogel was synthesized by microwave-assisted polymerization using 2-hydroxyethyl methacrylate (HEMA) as the raw material, potassium persulfate as the initiator, and PCLX as the cross-linking additive. The hydrogels was characterized with FTIR and NMR spectroscopy. The physical and chemical properties of the prepared hydrogel were evaluated, and its degradation performance was tested. The cytotoxicity of the optimum composite hydrogel was measured by an MTT assay to confirm the feasibility of its use in tissue engineering. RESULTS: The optimum conditions under which the hydrogel was prepared by microwave-assisted polymerization are as follows: 1.5 g cross-linking additive, 0.3 g initiator, reaction temperature of 80 °C, and microwave power of 800 W. Degradation studies showed good degradation profiles with 75% in 17 days. Additionally, the hydrogels did not elicit any cytotoxic response in in vitro cytotoxic assays. CONCLUSION: A biodegradable pHEMA hydrogel was successfully prepared by microwave-assisted polymerization, as confirmed from FTIR and NMR results. The hydrogel shows promising applications in tissue engineering, and its healing ability and biocompatibility will be evaluated in detail in the future.

Eysenck personality and psychosocial status of adult patients with malocclusion.

OBJECTIVE: To evaluate the personality and psychosocial status of adult malocclusion patients through the Eysenck Personality Questionnaire (EPQ) and the Symptom Checklist 90 (SCL-90). METHODS: The EPQ and the SCL-90 were administered to 348 adult respondents with Angle's Class I, II, III malocclusion and normal occlusion. Personality and psychosocial traits were analyzed and compared among the groups. RESULTS: Patients in Angle's Class I, II and III groups scored lower on the EPQ-E and higher on the EPQ-N than those in the normal occlusion group, whereas patients in the Class II group scored higher on the EPQ-P. The mean scores of Class I, II and III groups were significantly higher than those of the normal group on somatization, obsessive-compulsiveness, interpersonal sensitivity, depression, anxiety, and paranoid ideation. All SCL-90 scores were significantly positively correlated with EPQ-N. Psychoticism and neuroticism scores of female respondents were higher than those of male respondents. The impact of education was greatest on the EPQ-P and the EPQ-E of adult personality, whereas the impact of deformity was greatest on the EPQ-N of adult personality. CONCLUSIONS: Personality and psychosocial status show differences in adult patients with Class I, II, III malocclusion and normal occlusion and can be influenced by gender, deformity, age and education.

[Embolization and degradation of arteries in vivo by pingyangmycin albumin microspheres].

OBJECTIVE: To investigate the embolization effect of Pingyangmycin-albumin microspheres (PYM-AMS) on small arteries and its process of degradation in vivo. METHODS: Twenty four Japanese white rabbits were randomly divided into four groups, 6 in each group. PYM hydrochloride + 0.9% NaCl, PYM + soybean oil, and PYM-AMS + soybean oil were injected into the central auricular arteries of the rabbits in the three experimental groups, respectively, for about 30 seconds (0.26 mL/per ear, which contained PYM 5 mg/mL). The vessel samples were taken and examined at 2, 7, 14, and 21 days. RESULTS: The PYM + 0.9% NaCl group had no significant vessel changes. In the PYM+ soybean oil group, some endothelial cells dropped off at the 7th day after injection. At the 21st day, mild proliferation of endothelial cells and walls of central auricular arteries were observed, especially on the intima. But the lumen was still obvious and the blood flow was not blocked. In the PYM-AMS group, the central auricular arteries were narrowed at the 7th day after injection. At the 21st day, the vessels had sclerostenosis, and the blood flow was blocked. At the 14th day, significant proliferation of endothelial cells and walls of central auricular arteries were observed. The surface of PYM-AMS was absorbed. At the 21st day, the walls of central auricular arteries and some small veins proliferated obviously, and the arteries were sclerostenosed. Many smooth muscle cells, fibroblasts, and myofibroblasts in the original blood vessel lumen appeared. There were thrombi besides the PYM-AMS. CONCLUSION: PYM-AMS may become an option for the treatment of large venous or arteriovenous malformations and for the local chemotherapy of malignant tumors.

[Expression of mammary serine proteinase inhibitor in oral squamous cell carcinoma and its clinical significance].

OBJECTIVE: To investigate the expression of mammary serine proteinase inhibitor(Maspin) in patients with oral squamous cell carcinoma and its relationship with clinicopathological features. METHODS: The Maspin protein expression was examined in 45 patients with oral squamous cell carcinoma and in non-malignant oral epithelia by immunohistochemical staining. The relationship between the Maspin protein expression and the clinicopathological parameters was statistically analyzed. RESULTS: The Maspin protein expression in the cancerous tissues of oral squamous cell carcinoma was lower than that in the non-malignant oral epithelia (P = 0.001). Negative correlation was found between the Maspin protein expression in cancerous tissue and the status of lymph node metastasis (P = 0.038). Positive Maspin protein expression indicated negative lymph node metastasis, and negative correlation was also found between the Maspin protein expression and the postoperative metastasis (P = 0.004). Positive correlation was found between the Maspin expression and the patients' survival rate (P = 0.014), patients with positive Maspin protein expression having higher survival rate than those with negative Maspin expression. CONCLUSIONS: Maspin might be useful as a potential prognostic marker for oral squamous cell carcinoma.

[An experirmental study on the preparation and drug sustained release characteristics of Pingyangmycin Albumin Microspheres].

OBJECTIVE: The aim of this study was to prepare Pingyangmycin Albumin Microspheres (PYM-AMS) for arteriovenous malformations treatment. METHODS: PYM-AMS was prepared at 140 degrees C by the method of emulsification-heat solidification and its characteristics were evaluated, such as morphosis, particle size, drug loading (DL%), encapsulation efficiency (EE%), stability and drug sustained-releasing in vitro. After being packaged, PYM-AMS were sterilized with 13.7 kGy of 60Co. Small samples of PYM-AMS were packaged in small bottles and stored at 3 - 5 degrees C, 15 - 25 degrees C, 37 degrees C for 3 months, then checked the change of morphology, DL, EE and the release rate. RESULTS: The surface of particles was smooth and integrated. The average diameter of PYM-AMS particles was 139.422 microm and 80% was in the range of 56 - 251 microm. The mean DL% and EE% were 26.47% and 84.3%, respectively. PYM released fast in 5 h, but then released slowly. 88.65% drugs were released in 24 h, and t50 was 1.5 h. There was no obvious change of the morphology, DL,EE and the release rate of PYM-AMS stored at 3 - 5 degrees C 15 - 25 degrees C, 37 degrees C for 3 months. CONCLUSION: PYM-AMS prepared in this study had sustained-release effect, high drug loading and high stability. Albumin is a good carrier of PYM embolization agent.