Most drugs need to interact with cell membrane to reach the biological target, so that membrane affinity assay is an important early screening step in drug discovery. However, at present, the traditional oil-water distribution method is still used, a new, simple and accurate method for membrane affinity assay is urgently needed. In this study, according to the colorimetric principle, a new assay model based on polydiacetylene vesicles was optimized through a series of experiments including different concentrations of vesicle solution, temperature, or pH reaction environment. On this basis, tetracaine hydrochloride, 2-methylimidazole and histamine were used as model drugs to measure the membrane affinity constants and verify the between-batch precision of the optimized assay model (relative standard deviation less than 5%). In addition, polydiacetylene vesicles were stable for up to 180 days, demonstrating the potential application of the assay model. This strategy is simple, stable, reliable, with high reproducibility, low cost and easy to promote, which provided a new tool and a new direction for the high-throughput assay of membrane affinity.

OBJECTIVETo develop a novel scaffolding method for the copolymers poly lactide-co-glycolide acid (PLGA) to construct a three-dimensional (3-D) scaffold and explore its biocompatibility through culturing Schwann cells (SCs) on it.

METHODSThe 3-D scaffolds were made by means of melt spinning, extension and weaving. The queueing discipline of the micro-channels were observed under a scanning electronic microscope (SEM).The sizes of the micropores and the factors of porosity were also measured. Sciatic nerves were harvested from 3-day-old Sprague Dawley (SD) rats for culture of SCs. SCs were separated, purified, and then implanted on PLGA scaffolds, gelatin sponge and poly-L-lysine (PLL)-coated tissue culture polystyrene (TCPS) were used as biomaterial and cell-supportive controls, respectively. The effect of PLGA on the adherence, proliferation and apoptosis of SCs were examined in vitro in comparison with gelatin sponge and TCPS.

RESULTSThe micro-channels arrayed in parallel manners, and the pore sizes of the channels were uniform. No significant difference was found in the activity of Schwann cells cultured on PLGA and those on TCPS (P larger than 0.05), and the DNA of PLGA scaffolds was not damaged.

CONCLUSIONThe 3-D scaffolds developed in this study have excellent structure and biocompatibility, which may be taken as a novel scaffold candidate for nerve-tissue engineering.

Animals ; Biocompatible Materials ; Cell Adhesion ; Cell Proliferation ; Cell Separation ; Cells, Cultured ; Lactic Acid ; Microscopy, Electron, Scanning ; Polyglycolic Acid ; Rats ; Rats, Sprague-Dawley ; Schwann Cells ; cytology ; Tissue Engineering ; methods ; Tissue Scaffolds

Objective:To evaluate the clinical efficacy of"4-position"arthroscopic treatment of popliteal cyst in patients aged over 60.Methods:From June 2013 to June 2015,36 popliteal cyst patients aged over 60 with knee pain,swelling or limitation of activity were treated with arthroscopy.The fold of the joint capsule between the medial head of gastrocnemius muscle and the semimembranosus tendon was resected and enlarged up to 1 cm,and associated intra-articular diseases were treated at the same time.The preoperative and postoperative functions were evaluated with the Rauschning and Lindgren knee scores.Results:It was safe and convenient to build portals and work with 4-position.In 36 patients,34 cases(94.4%)had intra-articular diseases,24 cases(66.7%)had medial meniscus tear,10 cases(27.8%)had lateral meniscus tear,12 cases (33.3%)had cartilage lesion,and 8 cases(22.2%)had joint loose body.The follow-up time was 10-22 months,with an average of(16 ± 4)months.The symptoms of knee joint discomfort were significantly relieved after operation.The Rauschning and Lindgren scores were significantly lower than those before operation(P<0.01).Conclusions:Arthroscopic treatment of popliteal cyst patients aged over 60 with"4-position"is simple,safe,and effective,which can deal with intra-articular diseases at the same time.

BACKGROUNDPulmonary-vein isolation (PVI) is currently used for the treatment of chronic and paroxysmal atrial fibrillation and a major risk of PVI is thromboembolism. The purpose of this study was to observe embolic event rate in patients with persistent or paroxysmal atrial fibrillation (AF) undergone PVI.

METHODSCircumferential PVI (CPVI) was performed in 64 consecutive patients with persistent AF (42 men, aged (60.0 +/- 9.1) years) and in 84 consecutive patients with paroxysmal AF (53 men, aged (61.4 +/- 9.3) years). Warfarin was administrated in all patients before ablation for at least 3 weeks ((5.2 +/- 2.6) weeks) and continued for at least 3 months post ablation with international normalized ratio (INR) of 2.0 - 3.0. During CPVI, intravenous heparin was given at a dose of 5000 - 8000 U or 75 - 100 U/kg, followed by 1000 U or 12 U/kg per hour.

RESULTSIn patients with persistent AF, 1 patient developed embolic event during ablation and 3 patients developed embolic events after ablation. In contrast, no thromboembolic event was observed in patients with paroxysmal AF (4/64 vs 0/84, P = 0. 033).

CONCLUSIONThromboembolic event rate related to CPVI is significantly higher in patients with persistent AF than that in patients with paroxysmal AF.

Adult ; Aged ; Atrial Fibrillation ; surgery ; Catheter Ablation ; Female ; Humans ; Male ; Middle Aged ; Postoperative Complications ; etiology ; Pulmonary Veins ; surgery ; Thromboembolism ; etiology

OBJECTIVETo investigate the number of drinking occasions per day and average amount consumed per drinking occasion of primary and middle school students in four cities of China, and understand the relationship among drinking occasion, average amount consumed per drinking occasion and total drinking water.

METHODSA total of 5914 primary and middle school students from Beijing, Shanghai, Guangzhou and Chengdu were selected using multiple-stage random sampling method, and 5868 students completed the study from September to October in 2011. The detailed information of amounts and types of daily drinking water was recorded by subjects using a 24 hours measurement for seven consecutive days. Analysis of the relationship among drinking occasion, average amount consumed per drinking occasion and total drinking water was carried out.

RESULTSThe daily total drinking water of subjects was (1089 ± 540) ml; the daily number of drinking occasions was (4.7 ± 1.8) times, with 79.1% (4639/5868) of subjects reporting 6 or less drinking occasions. The amount consumed per drinking occasion was (239 ± 96) ml, plain water (231 ± 112) ml, and beverages (237 ± 112) ml. The number of drinking occasions of subjects was positively correlated with total drinking water (r = 0.614, P < 0.05), and negatively correlated with the average amount consumed per drinking occasion (r = -0.211, P < 0.05). Total drinking water and the average amount consumed per drinking occasion was positively correlated (r = 0.598, P < 0.05).

CONCLUSIONThe number of drinking occasion of primary and middle school students more than 6 times was fewer in four cities of China, but the average amount of beverages consumed per drinking occasion was relatively more. With the increasing of drinking occasion, the average amount consumed per drinking occasion decreased, but total drinking water increased.

Adolescent ; Beverages ; Child ; China ; Diet Surveys ; Drinking ; Drinking Water ; Female ; Humans ; Male ; Students ; Surveys and Questionnaires ; Urban Population

【Objective】 To investigate the expression and significance of phosphorylated receptor tyrosine kinase(p-AXL) in diffuse large B cell lymphoma(DLBCL), and the clinical value of its co-expression with BCL-2 and /or c-MYC split gene. 【Methods】 Totally 118 cases of DLBCL were collected in the First Affiliated Hospital of Sun Yat-sen University from 2012 to 2017, and prepared as tissue array. p-AXL, c-MYC and BCL-2 proteins were detected by immunohistochemistry, and c-MYC split gene was detected by FISH staining. 【Results】 p-AXL protein was stained on tumor cells’membrane or in the cytoplasm of DLBCL cells. p-AXL was expressed more commonly in Non-GCB type than in GCB type. The expression of p-AXL was significantly correlated with the chemotherapy effect(P<0.01), and the expression of c-MYC split gene or BCL-2 protein separately(P<0.01). Co-expression of p-AXL and c-MYC, or BCL-2, or both of them was significantly correlated with the Hans typing(P<0.01). The PFS of p-AXL positive patients was obviously lower than that of p-AXL negative patients(P<0.05). The OS of p-AXL positive patients was also lower than that of the negative patients, but the difference had no statistical significance(P>0.05). Univariate analysis showed that p-AXL and male, p-AXL and Non-GCB type, p-AXL and c-MYC co-expression, p-AXL and c-MYC and/or BCL-2 co-expression were the risk factors for PFS and OS in DLBCL patients(P<0.05). Multivariate analysis showed that p-AXL positive in male(P<0.05) and p-AXL/c-MYC co-expression(P<0.01) were independent risk factors for PFS and OS in DLBCL patients. 【Conclusions】 p-AXL protein is expressed in DLBCL, and its expression is significantly related to the expression of c-MYC and BCL-2. p-AXL expression is associated with lower chemotherapy response rate, shorter progression-free survival and shorter overall survival. p-AXL/c-MYC co-expression or p-AXL positive in male may be an independent prognostic factor for DLBCL patients.

With the promotion and application of big medical data, non-interventional real-world evidence (RWE) has been used by regulators to assess the effectiveness of medical products. This paper briefly introduces the latest progress and research results of the RCT DUPLICATE Initiative launched by the research team of Harvard University in 2018 and summarizes relevant research experience based on the characteristics of China's medical service to provide inspiration and reference for domestic scholars to conduct related RWE research in the future.
Humans ; Randomized Controlled Trials as Topic ; Cognition ; Big Data ; Universities