Objective: To investigate the prevalence of BRAF V600E mutation in thyroid nodules and to analyze the relationship between BRAF V600E mutation and various clinicopathological features. Methods: BRAF V600E mutant gene test was done in 463 cases of thyroid nodules collected from April 2015 to July 2018 in Beijing Hospital. Pathologic sections of 444 cases of papillary thyroid carcinoma were reviewed and clinical information was collected.Statistical analysis of the relationship between BRAF V600E gene mutation and various clinicopathological features was performed with SPSS 21.0 statistical software. Results: There were 109 males and 354 females in the cohort, with a male to female ratio of 1.0∶3.2. The patient ranged in age from 16 to 82 years, with an average age of 46.1 years. The BRAF V600E mutation rates in papillary thyroid carcinoma, benign thyroid nodules and other thyroid carcinoma were 86.5%(384/444),0/15 and 1/4,respectively.There was significant correlation between BRAF V600E mutation and histological diagnosis of papillary thyroid carcinoma (P<0.05). There was no correlation with age, gender, multifocality, bilaterality, coexisting lymphocytic thyroiditis, nodular goiter, maximum diameter, capsule invasion, extrathyroidal extension and clinical stage (P>0.05). Conclusions BRAF V600E gene mutation is closely related to the occurrence of papillary thyroid carcinoma. BRAF V600E has significant value in the diagnosis of papillary thyroid carcinoma. While BRAF V600E mutation is related to the histological diagnosis, it shows no correlation with other clinicopathologic features. BRAF V600E mutation is not an independent prognostic factor in papillary thyroid carcinoma patients.

OBJECTIVE: To develop a cell-based system for the diagnosis of vitamin K-dependent coagulation factor deficiency 1 (VKCFD1). METHODS: In HEK293 cells stably expressing the reporter gene FIX-Gla-PC, the gamma-glutamyl carboxylase (GGCX) gene was knocked out by using CRISPR/Cas9 technology. Enzyme-linked immunosorbent assay (ELISA), DNA sequencing and Western blotting were used to identify the GGCX gene knockout cells. A quickchange point variant method was used to construct the GGCX variant. ELISA was used to assess the influence of GGCX variant on the activity of reporter gene. RESULTS: Two monoclonal cell lines with no reporter activity by ELISA was identified. Edition and knockout of the GGCX gene was confirmed by DNA sequencing and Western blotting. The activity of the reporter gene was recovered by transfection of the wild-type GGCX gene. Thereby two monoclonal cells with GGCX knockout were obtained. By comparing the wild-type and pathogenic GGCX variants, the reporter activity was decreased in the pathogenic variants significantly. CONCLUSION A cell-based system for the detection of GGCX activity was successfully developed, which can be used for the diagnosis of VKCFD1 caused by GGCX variants.

OBJECTIVETo investigate the expression of Girdin and its significance in Alzheimer's disease (AD).

METHODSFifty-nine autopsy cases from Department of Pathology, Beijing Hospital from January 1988 to December 2013, including 35 AD cases and 24 non-AD cases as control. Girdin and amyloid β-protein (Aβ) expression was evaluated immunohistochemically by EnVision method. The correlation between Girdin and Aβ was analyzed.

RESULTSGirdin expression was localized in the nucleus and/or cytoplasm. The expression rates of Girdin were 20.0% (7/35) in the AD group and 83.3% (20/24) in the non-AD group, respectively. The difference was significant (Yates's correction for continuity χ(2)=20.527, P<0.05). Girdin expression and Aβ deposition also correlated significantly (P<0.05).

CONCLUSIONSGirdin shows reduced expression in AD, and is correlated positively with Aβ deposition. This suggests that Girdin may play an important role in the occurrence and development of AD.