[Interleukin 34 (IL-34) promotes the proliferation and odontogenic differentiation of rat apical papillary stem cells].

Objective To investigate the effect of interleukin-34 (IL-34) on the odontogenic and osteogenic differentiation of stem cells from the apical papilla (SCAPs) in rats. Methods SCAPs were isolated and cultured by enzyme digestion method, and the expression of IL-34 in SCAPs was detected by real-time fluorescence quantitative PCR(RT-PCR). MTT assay was used to analyze the effects of different concentrations of IL-34 on SCAPs' proliferation in rats. The mineralization was observed by alizarin red staining, and the proliferation capacity was detected by scratch test. The expressions of alkaline phosphatase (ALP), dentin sialophosphoprotein (DSPP), runt-related transcription factor 2 (Runx2) and critical transcription factor osterix (OSX) were detected by RT-PCR. The protein expressions of ALP, DSPP, Runx2 and OSX were detected by Western blot analysis. Results The maximum concentration of IL-34 promoting the proliferation of SCAPs in rats was 100 ng/mL. Aalizarin red staining showed that IL-34 could promote the mineralization of SCAPs. RT-PCR and Western blot analysis showed that 100 ng/mL IL-34 could promote the expression of ALP, DSPP, Runx2 and OSX. Conclusion IL-34 can promote the proliferation and odontogenic/osteogenic differentiation of SCAPs in rats.

In vitro corrosion resistance and dual antibacterial ability of curcumin loaded composite coatings on AZ31 alloy: Effect of amorphous calcium carbonate.

Rapid corrosion and bacterial infection are obstacles to put into use biodegradable magnesium (Mg) alloy as biomedical materials. In this research, an amorphous calcium carbonate (ACC)@curcumin (Cur) loaded poly-methyltrimethoxysilane (PMTMS) coating prepared by self-assembly method on micro-arc oxidation (MAO) coated Mg alloy has been proposed. Scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy are adopted to analyze the morphology and composition of the obtained coatings. The corrosion behaviour of the coatings is estimated by hydrogen evolution and electrochemical tests. The spread plate method without or with 808 nm near-infrared irradiation is applied to evaluate the antimicrobial and photothermal antimicrobial ability of the coatings. Cytotoxicity of the samples is tested by 3-(4,5)-dimethylthiahiazo(-z-y1)-2,5-di- phenytetrazoliumromide (MTT) and live/dead assay culturing with MC3T3-E1 cells. Results show that the MAO/ACC@Cur-PMTMS coating exhibited favourable corrosion resistance, dual antibacterial ability, and good biocompatibility. Cur was employed as an antibacterial agent and photosensitizer for photothermal therapy. The core of ACC significantly improved the loading of Cur and the deposition of hydroxyapatite corrosion products during degradation, which greatly promoted the long-term corrosion resistance and antibacterial activity of Mg alloys as biomedical materials.

Radiation-induced osteosarcoma of the maxilla and mandible after radiotherapy for nasopharyngeal carcinoma.

BACKGROUND: The increasing incidence of radiation-induced osteosarcoma of the maxilla and mandible (RIOSM) has become a significant problem that can limit long-term survival. The purpose of this study was to analyze the association of clinicopathologic characteristics with treatment outcomes and prognostic factors of patients who developed RIOSM after undergoing radiotherapy for nasopharyngeal carcinoma (NPC). METHODS: We reviewed the medical records of 53,760 NPC patients admitted to Sun Yat-sen University Cancer Center during the period August 1964 to August 2012. Of these patients, 47 who developed RISOM and met inclusion criteria were included in this study. Two of these 47 patients refused treatment and were then excluded. RESULTS: For all patients treated for NPC at Sun Yat-sen University Cancer Center during the study period, the total incidence of RIOSM after radiotherapy was 0.084% (47/53,760). Two patients (4.4%) had metastases at the diagnosis of RIOSM. Thirty-nine of the 45 (86.7%) patients underwent surgery for RIOSM; most patients (24/39; 61.5%) who underwent resection had gross clear margins, with 15 patients (38.5%) having either a gross or microscopic positive margin. All patients died. The 1-, 2-, and 3-year overall survival (OS) rates for the entire cohort of 45 patients were 53.3%, 35.6% and 13.5%, respectively. The independent prognostic factors associated with high OS rate were tumor size and treatment type. CONCLUSIONS: RISOM after radiotherapy for NPC is aggressive and often eludes early detection and timely intervention. Surgery combined with postoperative chemotherapy might be an effective treatment to improve patient survival.

Survival impact of cervical metastasis in squamous cell carcinoma of hard palate.

OBJECTIVE: Evaluate the impact of cervical metastasis on the survival of patients with squamous cell carcinoma (SCC) of the hard palate. METHODS: 155 cases of SCC of the hard palate hospitalized in Cancer Center, Sun Yat-sen University, from 1964 to 2008 were reviewed retrospectively. RESULTS: The 5-year DSS rates for N+ and N0 patients were 21.54% and 47.36% (P = .048). The 5-year DSS rates were 47.36%, 27.48%, 15.55% and 0 for N0-N3 lesions, respectively (P = .041). Cervical metastasis was detected in 40% patients for initial consultation. After therapy, those individuals who presented with clinically negative necks had a 9.03% rate of cervical metastasis. Ultimately, 49.03% of patients manifested disease to the cervical lymph nodes. CONCLUSION: The presence of cervical nodal disease in patients is associated with the decreased survival rates. SCC of the hard palate should be treated aggressively, and elective neck dissection should be considered because of the high rate of cervical metastasis.

Long-term treatment outcome of minor salivary gland carcinoma of the hard palate.

Minor salivary gland carcinoma of the hard palate is rare, and its long-term survival rate is high, making it difficult to evaluate the prognostic factors and the efficacy of treatment. This study was designed to evaluate the treatment outcome of minor salivary gland carcinoma of the hard palate. 103 cases of minor salivary gland carcinoma of the hard palate treated with surgery alone or underwent surgery combined with post-operative radiotherapy hospitalized in Cancer Center, Sun Yet-Sen University, from 1968 to 2008 were reviewed retrospectively. The most common histologic types were adenoid cystic carcinoma in 48 patients(46.6%), mucoepidermoid carcinoma in 37(35.92%), malignant mixed tumor in 15(14.56%), and acinic cell carcinoma in 3(2.91%). The median follow-up time was 74.83 months (range 0.9-356.57 months). Overall outcomes at 5 and 10 years were overall survival (OS), 77.9% and 65.7%; recurrence-free survival (RFS), 64.4% and 53.2%; and disease specific survival (DSS), 77.9% and 67.7%, respectively. There was no significant difference in overall survival (P=0.52), recurrence-free survival (P=0.762) and disease specific survival (P=0.449) between patients who underwent surgery alone and those who underwent surgery plus post-operative radiotherapy. Surgery has been accepted as the primary treatment for minor salivary gland carcinoma of hard palate. Sufficient surgical excision with adequate margins is essential for a favorable outcome. We advocate using radiotherapy in the post-operative context for patients with poorly differentiated, cervical lymph node metastasis, positive or close margins, and large primary lesions.

[Primary effect of submandibular salivary gland transfer in preventing radiation-induced xerostomia of nasopharyngeal carcinoma].

BACKGROUND & OBJECTIVE: Xerostomia, an ubiquitous sequelae in nasopharyngeal carcinoma (NPC) patients after radiotherapy, seriously affects life quality of the patients. This study was to investigate clinical value of submandibular salivary gland transfer in preventing radiation-induced xerostomia of NPC patients. METHODS: A total of 70 eligible patients with NPC were recruited, and divided into test group (36 patients) and control group (34 patients). In test group, the submandibular glands were transferred to the submental spaces before conventional radiotherapy. The submental spaces were shielded during radiotherapy. Oral cavity mucous membrane reaction during radiotherapy, submandibular gland function and salivary fluid before and after radiotherapy, and questionnaire of xerostomia 3 months after radiotherapy were compared between test group and control group. RESULTS: Acute oral cavity mucous membrane reaction was severer in control group than in test group; the incidence of stage III reaction was significantly higher in control group than in test group ( 8/34 vs. 3/36, P = 0.007). Three months after radiotherapy, trapping and excretion functions of the transferred submandibular glands were significantly better than those of the untransferred submandibular glands in test group (P = 0.001 and P = 0.000); trapping and excretion functions of the submandibular glands were significantly better in test group than in control group (P = 0.004 and P = 0.000). The mean weight of salivary fluid after radiotherapy was heavier in test group than in control group (1.41 g vs. 0.71 g). Incidence of moderate to severe degree of xerostomia was significantly higher in test group than in control group (76.5% vs. 13.9%, P = 0.000). CONCLUSION: Submandibular gland transfer may be used to prevent radiation-induced xerostomia of NPC patients, and may improve life quality of the patients.

[Clinical analysis of xerostomia in patients with nasopharyngeal carcinoma after radiation therapy].

BACKGROUND & OBJECTIVE: There is few report on the xerostomia of the patients with nasopharyngeal carcinoma after conventional radiation therapy. Xerostomia is a serious, permanent, and ubiquitous sequelae in the patients with nasopharyngeal carcinoma after conventional radiation therapy. It has a significant impact on the patient's quality of life. This study was designed to investigate the severity of xerostomia and its impact on the quality of life in patients with nasopharyngeal carcinoma after conventional radiation therapy. METHODS: One hundred and thirty-six patients with nasopharyngeal carcinoma, treated by conventional radiation therapy in Cancer Center, Sun Yat-sen University, were surveyed by interview at the outpatient. A questionnaire and a visual analog scale (VAS) were used in analysis of xerostomia and xerostomia-related problems. RESULTS: Of 136 patents, 73.5% of the patients experienced a moderate to severe degree of xerostomia. 82.4% of the patients had to sip water to facilitate speech; 92.6% of the patients had to sip water to facilitate chewing and swallowing; 91.2% of the patients changed their feeding pattern (can eat only mashed food); 61.3% of the patients had to wake up to drink water because of dry mouth; 75.0% of the patients had teeth deteriorated. CONCLUSION: 73.5% of the patients with nasopharyngeal carcinoma after conventional radiation therapy experienced a moderate to severe degree of xerostomia. Xerostomia has a significant impact on the patient's speech, deglutition, sleep, and increases the morbidity rate of the tooth.

[Effectiveness evaluation and prognostic factor analysis in patients with minor salivary gland carcinoma of the hard palate].

BACKGROUND & OBJECTIVE: Minor salivary gland carcinoma of the hard palate is rare, and its long-term survival rate is high, making it difficult to evaluate the prognostic factors and the efficacy of treatment. This study was designed to evaluate the efficacy of treatment and investigate the prognostic factors of minor salivary gland carcinoma of the hard palate. METHODS: Ninety-six cases of minor salivary gland carcinoma of the hard palate hospitalized in Cancer Center, Sun Yat-sen University, from 1964 to 2001 were reviewed retrospectively. The cumulative survival rate was analyzed by Kaplan-Meier method. The factors were compared using the log-rank test. The influencing factors were screened by Cox proportional hazards model. RESULTS: The 5- and 10-year overall survival rates were 65.60% and 47.90%, respectively. The 5- and 10-year disease-specific survival rates for the patients treated with surgery (53 cases) and surgery + radiotherapy (35 cases) were 73.14%, 67.40% and 66.58%,46.60%,respectively. Multivariate analysis showed that age >or=50 years old,tumor size >or=3 cm,surgical margin status,and recurrence were independently associated with decreased survival rates (P< 0.05). CONCLUSION: Surgery or surgery dominated multi-modality therapy was the principal treatment modality for minor salivary gland carcinoma of the hard palate. Age >or=50 years old, tumor size >or=3 cm, surgical margin status, and recurrence are independent factors affecting the prognosis.