Electronic structure characteristics of two-dimensional ferroelectric heterostructuresα-In2Se3/ZnSe.

At present, chips urgently need breakthrough development in the power consumption and integration. The chip integrates billions or even tens of billions of electronic components, such as field effect transistor, diode and so on. Therefore, the research and development of new low-power electronic components with smaller size is an effective method to reduce chip power consumption and improve chip integration. In this paper, the ferroelectric field effect transistor (Fe-FET) based on two-dimensional heterostructuresα-In2Se3/ZnSe is proposed. Based on the first principle, the program will analyze the stability and band structure ofα-In2Se3/ZnSe under different stacking modes. In the heterojunction, the microphysical mechanism of ferroelectric polarization affecting the electronic structure is revealed from the aspects of charge transfer at the interface and the asymmetric surfaces with different work function. Combined with the non-equilibrium Green's function transport theory, the transport properties of Fe-FET based on theirα-In2Se3/ZnSe will be studied. The application will provide sufficient theoretical support for research and development of the device based onα-In2Se3/ZnSe structure.

An arthroscopic "inlay" Bristow procedure with suture button fixation: Surgical technique and radiology evaluation / 北京大学学报(医学版)

OBJECTIVE@#To introduce an arthroscopic "inlay" Bristow procedure based on the Mortise-Tenon joint structure concept using suture button fixation, and to evaluate its clinical and radiology results postoperatively with a minimal 3-year follow-up.@*METHODS@#A total of 56 patients who received arthroscopic "inlay" Bristow procedure with suture button fixation between June 2015 to June 2016 were eventually enrolled in this study. Radiological assessment on the 3D CT scan was performed preoperatively, immediately after operation, and postoperatively at the end of 3 months, 6 months and the final follow-up. Complications postoperatively were also recorded.@*RESULTS@#A total of 56 patients were finally included in this study. The mean follow-up time was (36.1±3.7) months. Coracoid grafts (middle point) were positioned at about 4 o'clock (123.8°±12.3°) in the En-face view. In the axial view, 95% (53/56) of the grafts positioning were measured as flush, 5% (3/56) as medial. Bone union rate was 96.4% at the final follow-up. At the end of 3 months, 6 months, and the final follow-up, the length of the coracoid graft was 96.9%±4.9%, 91.9%±6.2%, and 91.6%±6.6% of the immediate postoperative length, respectively. Compared with the immediate postoperative length, the length measured at the end of 3 months shortened not significantly (t=2.12, P > 0.05). The coracoid graft shortened more pronouncedly 6 months postoperatively (t=4.98, P < 0.05) and then remained almost constant over time (t=-0.75, P > 0.05), with all grafted coracoid graft retaining more than 90% of their initial length by the 3-year follow-up. And new bone formation at the junction between the coracoid graft and glenoid neck in the axial view were obviously noted in 25 cases. The quantitative evaluation showed that the glenoid area in En-face view was significantly increased at the final follow-up than that immediately after surgery [(9.72±1.22) cm2 vs. (9.42±1.11) cm2]. No degenerative changes were noted on CT images in all the patients at the final follow-up.@*CONCLUSION@#This study reported a series of "inlay" Bristow procedure with suture button fixation for recurrent shoulder dislocation, providing satisfactory union rate and excellent graft positioning. And using suture button fixation instead of screw can reduce osteolysis and complications related to hardware implantation. Moreover, the bone remodeling between the coracoid process and glenoid could be beneficial to restoring the anterior stability of shoulder joint in a long term follow-up.

Sensitive Analysis and Pharmacokinetic Study of Berberrubine Using LC-MS/MS / 中草药·英文版

Objective To develop a sensitive and reproducible liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to evaluate the pharmacokinetic behavior of berberrubine (BRB) and its glucuronide (BRBG) in rats. Methods BRB, BRBG and tetrahydroberberine (THB, internal standard) were isolated by liquid-liquid extraction in rat biological samples. Chromatographic separation was achieved on an Agilent Zorbax Eclipse Plus C18 (2.1 mm × 50 mm, 3.5-Micron) with a gradient mobile phases primarily containing acetonitrile, water with 0.1% formic acid and 5 mm ammonium acetate. The analytes were monitored by MS/MS in positive electrospray ionization mode. Herein, the feasibility of new developed method was validated with respect to specificity, linearity, precision, accuracy, stability, extraction efficiency and matrix effect. The appropriate method was used for the pharmacokinetic study in rats. Results The new developed method could be applied to the pharmacokinetic study of BRB in rats. BRB and BRBG showed good linearity over the ranges of 2-1000 ng/mL and 5-2000 ng/mL, respectively, and precision was no more than 15%. The accuracy, specificity and stability could be acceptable. Conclusion The new method is sensitive and reproducible. In pharmacokinetic study, BRB showed nonlinear elimination property. Meanwhile, BRB was rapidly absorbed and widely distributed in various tissues with the highest exposure of BRB in kidney and liver. The absolute bioavailability of BRB was determined to be 8.2% and at the dose of 40 mg/kg, a total of 44% BRB was excreted in urine and feces.

Pharmacokinetics of the prototype and hydrolyzed carboxylic forms of ginkgolides A, B, and K administered as a ginkgo diterpene lactones meglumine injection in beagle dogs / 中国天然药物

Ginkgo diterpene lactones meglumine injection (GDLI) is a commercially available product used for neuroprotection. However, the pharmacokinetic properties of the prototypes and hydrolyzed carboxylic forms of the primary components in GDLI, i.e., ginkgolide A (GA), ginkgolide B (GB), and ginkgolide K (GK), have never been fully evaluated in beagle dogs. In this work, a simple, sensitive, and reliable method based on ultra-fast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS) was developed, and the prototypes and total amounts of GA, GB, and GK were determined in beagle dog plasma. The plasma concentrations of the hydrolyzed carboxylic forms were calculated by subtracting the prototype concentrations from the total lactone concentrations. For the first time, the pharmacokinetics of GA, GB, and GK were fully assessed in three forms, i.e., the prototypes, the hydrolyzed carboxylic forms, and the total amounts, after intravenous administration of GDLI in beagle dogs. It was shown that ginkgolides primarily existed in the hydrolyzed form in plasma, and the ratio of hydrolysates to prototype forms of GA and GB decreased gradually to a homeostatic ratio. All of the three forms of the three ginkgolides showed linear exposure of AUC to the dosages. GA, GB, and GK showed a constant half-life approximately 2.7, 3.4, and 1.2 h, respectively, which were consistent for the forms at three dose levels (0.3, 1.0, and 3.0 mg·kg) and after a consecutive injection of GDLI for 7 days (1.0 mg·kg).

Effects of broth culture filtrate protein of VacA+ Helicobacter pylori on the proliferation and apoptosis of gastric epithelial cells / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Infection with Helicobacter pylori (H. pylori) may lead to chronic inflammation of the stomach epithelium, mucosal atrophy, imbalance of proliferation and apoptosis of epithelial cells; resulting in chronic gastritis, peptic ulcer, gastric cancer, and many other clinical outcomes. Why and how H. pylorus leads to gastric cancer is not clear yet. Through in vitro experiments, this study evaluated the effects of broth culture filtrate protein (BCF-P) from the supernatant of liquid culture media of H. pylori on proliferation and apoptosis of immortalized human gastric epithelial cell lines (GES-1) and gastric cancer cell lines (AGS).</p><p><b>METHODS</b>For the study, GES-1 and AGS cell lines mix with BCF-P and epidermal growth factor (EGF). MTT assay and flow cytometry (FCM) determined the levels of proliferation and apoptosis. Detected expression levels of cyclooxygenase-2 (COX-2) and Fas mRNA by reverse transcription (RT)-PCR. Also did analysis of the effects of BCF-P on epidermal growth factor receptor (EGFR) tyrosine kinase activity of GES-1 and AGS cells by non-radioactive enzyme-linked assay. The Student's t test and one-way analysis of variance (ANOVA) were used for statistical analysis.</p><p><b>RESULTS</b>BCF-P inhibited proliferation of GES-1 and AGS cells in a concentration-dependent manner. The inhibition rates are respectively 68.7% in AGS and 61.4% in GES-1. With the same dose and time for inhibiting the proliferation, BCF-P failed to induce apoptosis of GES-1 and AGS cells. Effects of BCF-P reduced the expression of Fas mRNA of GES-1 and AGS cells (P < 0.05). This is consistent with the effects of EGF. BCF-P reduced the expression of COX-2 mRNA of AGS cells (P < 0.05). This is opposite to the effects of EGF (P < 0.05). Effects of BCF-P improved more than three times the EGFR tyrosine kinase activity of GES-1 and AGS cells.</p><p><b>CONCLUSIONS</b>BCF-P inhibited the proliferation of AGS and GES-1 cells in vitro, unrelated to apoptosis. Effects of BCF-P on gastric epithelial cells in vitro are not equivalent to that of EGF.</p>

Advances in studies on chemical constituents and biological activities of Lawsonia inermis / 中国中药杂志

Lawsonia inermis is a single-species genus of the Lythraceae family, its leaves, stem bark, roots, flowers and seeds have been used in traditional medicine. It has been paid more attention by scholars from many countries because of their various types of compounds and significant physiological activities. The plant is reported to contain quinones, phenylpropanoids, flavonoids, terpenoids, phenolic compounds and fatty acids. Modern pharmacological studies have demonstrated that the plant performs antimicrobial, antioxidant, anticancer and antiparasitic activity. This article mainly summarizes the research advances of chemical constituents and biological activities of Lawsonia inermis, for its further development and utilization.