At present,the most commonly used method for detecting hemagglutinin(HA)content in influenza vaccines is still single-radial immunodiffusion(SRID). However,the preparation of standards required by this method takes a long time,usually 2 ～ 3 months. Therefore,how to quantitatively analyze HA accurately has always been a difficult problem in the detection of HA content in the situation that reference products can not be obtained at the early stage of the pandemic influenza. High performance liquid chromatography(HPLC)has its own characteristics of rapidity,high sensitivity,good repeatability and high accuracy,which can rapidly determine HA content by using different separation principles and has been widely used in the detection of HA content in influenza vaccine. This paper reviewed the research progress of the application of HPLC in the determination of HA content in influenza vaccine.

ObjectiveTo express the receptor binding domain(RBD)protein of severe acute respiratory symptom coronavirus 2(SARS-CoV-2)in soluble form by prokaryotic system and evaluate its immunogenicity by immunizing mice with the purified protein,so as to provide a new idea for the preparation of SARS-CoV-2 candidate vaccine.MethodsSARS-CoV-2RBD gene fragment was amplified and ligated with pNCMO2 vector after enzyme digestion. The obtained recombinant prokaryotic expression plasmid pNC-RBD was transformed into Bacillus choshinensis competent cells,which were subjected to expanded culture and induced by lowering temperature. The target protein was purified by affinity chromatography,adsorbed by aluminum hydroxide adjuvant,and then the female BALB/c mice were immunized subcutaneously in the back using the protein,10 mice for each group,with the aluminum adjuvant-free protein as control. The humoral immunity was measured by ELISA,while the cellular immune effect by proliferation assay in vitro. The secretion of various cytokines in vitro was measured by ELISA,and the cell typing was determined by flow cytometry.ResultsThe recombinant expression plasmid pNC-RBD was constructed correctly as identified by colony PCR and sequencing. The recombinant protein had a relative molecular mass of about 22 000,which could be expressed and secreted,and the purity of recombinant protein after purification was over 95%. The titers of binding antibody and neutralizing antibody in serum of the immunized mice were about 1∶10 000 and 1∶750,respectively,which were significantly higher than those in adjuvant group(t = 2. 845 and 2. 528,respectively,each P < 0. 01). The recombinant protein stimulated lymphocyte proliferation and promoted the secretion of IL-1β and IFNγ in vitro. The results of cell typing test showed that the lymphocyte proliferation of both CD4~+ and CD8~+T cells was promoted.ConclusionThe RBD protein of SARS-CoV-2 was successfully expressed in soluble form with good immunogenicity,which lays a foundation for the development of SARS-CoV-2 genetic engineering vaccine based on RBD protein.

Objective To evaluate clinical application of thyroid fine-needle aspiration biopsy (FNAB) and its diagnostic value.Methods FNAB was performed for 782 cases during 2005-2009 at China-Japan Friendship Hospital,Beijing and their clinical pathological data were retrospectively analyzed.Cytopathological diagnoses by FNAB were classified as unsatisfactory,benign,atypical cellular lesions,follicular neoplasm,suspicious malignancy and definite malignancy.Results of thyroid cytological and histological examinations of 76 patients with subsequent thyroidectomies were compared to those with FNAB to evaluate its diagnostic accuracy.Results Of 782 FNAB specimens,74.4 % (582/782) were classified as benign,2.6 % (20/782) as malignant,5.6 % (44/782) as follicular neoplasm,3.2 % (25/782) as atypical cellular lesion,2.9% (23/782) as suspicious malignancy and 11.3 % (88/782) as unsatisfactory.Among 76 patients with thyroidectomies,65.8 % of them (50/76) were histologically diagnosed as benign lesion,28.9 % (22/76) as definite malignancy and only 5.3 % (4/76) as benign follicular adenoma.Agreement between FNAB cytological diagnoses and histologically confirmed diagnoses for benign lesion and malignancy was 16/16 and 16/17,respectively.Conclusion FNAB is a reliable diagnostic method for evaluation of thyroid nodules.

Objective To investigate the diagnostic value of fine-needle aspiration(FNA) for thyroid nodules.Methods The cytological and histological results of 74 patients who had undergone FNAs for thyroid nodules,followed by thyroidectomy,were compared to evaluate the accuracy of cytological diagnosis of thyroid FNA and analyze the common causes of missed diagnosis and misdiagnosis in thyroid cytopathology.Results Benign lesions were histologically diagnosed in 48 patients(65%),malignant tumors in 22 cases(30%) and benign tumors in 4 cases(5%).Cytological diagnosis of benign and malignancy was confirmed histolopathologically in 96% and 94%,respectively.Fifteen discrepant cases came mainly from the group of FNA diagnosis of follicular neoplasm,and the discrepancies resulted mainly from cytodiagnostic errors and overlapping cytological features between adenomatoid nodule and follicular neoplasm.Conclusion Despite some limitations,thyroid fine-needle aspiration is a reliable diagnostic method of assessing thyroid nodular disease,especially in differentiation of benign lesion and malignant lesion.

Objective To investigate the clinical characteristics of primary thyroid lymphoma(PTL) and its prognostic factors.Methods Clinical and pathological data of 7 cases diagnosed as primary thyroid lymphoma were retrospectively analyzed.Results All of the 7 patients were diagnosed on thyroidectomy and presented with thyroid nodules,of whom 6 cases were middle-aged to elderly women and some had locally oppressive symptoms.Four cases were diagnosed as diffuse large B non-Hodgkin's lymphoma (DLBCL) and 3 were mucosa-associated lymphoid tissue B-cell lymphoma (MALT).Pathological subtype of mucosa-associated lymphoid tissue B-cell lymphomas and younger patients had better prognosis.Conclusion The possibility of PTL must be kept in mind in the differential diagnosis of thyroid nodules in middle-aged to elderly women.Age and pathological subtype are important prognostic factors.

Objective To analyze the clinical efficacy of transcatheter tricuspid valve replacement (TTVR) in cardiac implantable electronic lead-related tricuspid regurgitation (TR). Methods The patients with severe TR who underwent LuX-Valve TTVR in 9 Chinese medical centers from June 2020 to August 2021 were retrospectively enrolled. They were divided into a cardiac implantable electronic device (CIED) group and a non-CIED group based on whether they had pre-existing CIED implantation. Success of the procedure was defined as safe implantation of the LuX-Valve and complete withdrawal of the delivery system. Prognostic improvement was defined as a decrease of TR grade to≤2+ and an improvement of cardiac function by≥2 grades. Surgical success and postoperative prognosis were compared between the two groups. Results A total of 190 patients were collected, including 50 males and 140 females with a mean age of 66.2±7.8 years. There were 29 patients in the CIED group, and 161 patients in the non-CIED group. In the CIED group, 28 patients were implanted with a permanent pacemaker and 1 patient with a cardioverter-defibrillator. Preoperative New York Heart Association (NYHA) cardiac function class, TR degree, left ventricular ejection fraction, tricuspid annular plane systolic excusion, and cardiac risk scores were comparable between the two groups (P>0.05). Postoperative TR was reduced to≤2+ in all patients, and there was no statistical difference in the incidence of perivalvular leakage between the two groups (P=0.270). Postoperative CT of CIED patients showed the valve was in place, and the lead was not extruded, twisted, or deflected. The in-hospital mortality of the two groups were 10.3% and 1.9%, respectively, and the difference was statistically significant (P=0.047). In addition, there was no statistical difference between the two groups in terms of postoperative improvement of cardiac function and mortality in the 1- and 2-year follow-up. Conclusion TTVR is feasible, safe, and effective in patients with CIED implantation, and the pre-existing lead has no significant effect on the clinical efficacy.