Enhanced Dissolution and Bioavailability of Curcumin Nanocrystals Prepared by Hot Melt Extrusion Technology.

Purpose: Curcumin nanocrystals (Cur-NCs) were prepared by hot melt extrusion (HME) technology to improve the dissolution and bioavailability of curcumin (Cur). Methods: Cur-NCs with different drug-carrier ratios were prepared by one-step extrusion process with Eudragit® EPO (EEP) as the carrier. The dispersed size and solid state of Cur in extruded samples were characterized by dynamic light scattering (DLS), scanning electron microscope (SEM), differential scanning calorimetry (DSC), and X-ray diffraction (XRD). The thermal stability of Cur was analyzed by thermogravimetric analysis (TGA) and high performance liquid chromatography (HPLC). Dissolution and pharmacokinetics were studied to evaluate the improvement of dissolution and absorption of Cur by nano-preparation. Results: Cur-NCs with particle sizes in the range of 50~150 nm were successfully prepared by using drug-carrier ratios of 1:1, 2:1 and 4:1, and the crystal form of Cur was Form 1 both before and after HME. The extrudate powders showed very efficient dissolution with the cumulative dissolution percentage of 80% in less than 2 min, and the intrinsic dissolution rates of them were 13.68 ± 1.20 mg/min/cm2, 11.78 ± 0.57 mg/min/cm2 and 4.35 ± 0.20 mg/min/cm2, respectively, whereas that of pure Cur was only 0.04 ± 0.00 mg/min/cm2. The TGA data demonstrated that the degradation temperature of Cur was about 250 °C, while the HPLC results showed Cur was degraded when extruded at the temperature over 150 °C. Pharmacokinetic experiment showed a significant improvement in the absorption of Cur. The Cmax of Cur in the Cur-NC group was 1.68 times that of pure Cur group, and the Cmax and area under the curve (AUC0-∞) of metabolites were 2.79 and 4.07 times compared with pure Cur group. Conclusion: Cur-NCs can be prepared by HME technology in one step, which significantly improves the dissolution and bioavailability of Cur. Such a novel method for preparing insoluble drug nanocrystals has broad application prospects.

[BRAF V600E expression in ameloblastomas, ameloblastic carcinomas and cysts].

PURPOSE: To investigate protein and genetic status of BRAF V600E in ameloblastomas, ameloblastic carcinomas and cysts, and to explore if recurrence and malignant transformation of ameloblastomas depends on BRAF status. METHODS: Twenty cysts, 25 primary ameloblastomas, 25 recurrent ameloblastomas and 8 ameloblastic carcinomas were analysed by immunohistochemistry, and 2 cysts, 5 primary ameloblatomas, 5 recurrent ameloblastomas, 3 atypical ameloblastomas and 6 ameloblastic carcinomas were analysed by quantitative real-time PCR(qPCR). SPSS 26.0 software package was used for data analysis. RESULTS: There was no correlation between BRAF V600E expression and recurrence. Cysts and carcinomas had lower frequencies of BRAF V600E mutations than ameloblastomas. There was a concordance between positive staining of BRAF V600E protein and BRAF V600E mutation. CONCLUSIONS: BRAF V600E mutation may be useful in the differential diagnosis of ameloblastomas with cysts and ameloblastic carcinomas. Immunohistochemistry may be a beneficial method to screen for BRAF V600E mutation in ameloblastoma.

[Expression and clinical significance of NEK2 and EMT related molecules in oral squamous cell carcinoma].

PURPOSE: To investigate the expression and significance of NEK2 and EMT-related molecules in oral squamous cell carcinoma (OSCC). METHODS: The expression levels of NEK2 and EMT-related molecules (E-Cadherin, N-Cadherin, Vimentin) in 60 cases of primary OSCC tissues and normal oral mucosa tissues were detected by immunohistochemistry(IHC). NEK2 mRNA expression in 25 OSCC tissues and 10 normal oral mucosa tissues was detected by qRT-PCR. Statistical analysis was performed using SPSS 26.0 software package. RESULTS: The expression of NEK2, N-Cadherin, and Vimentin increased in OSCC tissues, while the expression of E-Cadherin decreased(P＜0.05). The worse the differentiation, the higher the expression of NEK2 and the lower the expression of E-Cadherin(P＜0.05). CONCLUSIONS: NEK2 can be used as a prognostic marker for OSCC. The up-regulation of NEK2 and the changes in the expression levels of EMT related molecules can promote the occurrence and development of OSCC.

[Atypical solitary fibrous tumor of the buccal mucosa: report of 1 case].

Solitary fibrous tumor is often considered to be a mesenchymal tumor. We reported a case of atypical SFT of the buccal mucosa in a 56-year-old male patient. We found hypercellularity, nuclear atypia, increased number of mitotic figures(more than 4 per 10 high-power fields) microscopically. A long-term follow-up is necessary after complete excision.

[Clinical and pathological analysis of 8 patients with oral candidiasis].

PURPOSE: To investigate the clinical and pathological diagnosis of oral candidiasis and reduce misdiagnosis. METHODS: The medical records of 8 patients with oral candidiasis were reviewed retrospectively, HE and PAS staining of histopathology were applied to study the specimens. RESULTS: It was found that oral candidiasis were identified by pathological diagnosis, but weren't considered clinically. Minor abscesses were all detected in the epithelium of conventional histopathologic sections, the hyphae were shown by PAS staining invading the epithelium. CONCLUSIONS: The results suggest that candidal infections should be considered, if there are hyperplastic or ulcerative lesions which last for long time; when minor abscesses are detected in the epithelium by histopathologic examination, oral candidiasis should be highly suspected, and be confirmed by PAS staining.