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Threshold switching (TS) devices based on NbOx materials show intriguing potential for constructing artificial neurons in a neuromorphic machine. However, the high electroforming voltage, the low TS yield, and the poor device uniformity hinder the practical application of NbOx-based TS devices. In this work, we systematically investigate the effect of film composition on device performance by adjusting the oxygen contents in the NbOx films. The electroforming voltage decreases with lowering the oxygen content, and the forming yield for activating TS behavior increases without an additional reset process. Moreover, we propose a stacked method by inserting a NbOy layer with high oxygen content between the low oxygen NbOx layer and the bottom electrode. The intercalated NbOy layer serves as a virtual bottom electrode after breakdown, enhancing the local electrical field and improving cycle-to-cycle stability and device-to-device uniformity. These results demonstrate that the device performances are greatly improved by optimizing the oxygen content and structure, guiding for practical applications of NbOx-based TS devices in neuromorphic computing. [ABSTRACT FROM AUTHOR]

Herein, four novel 4-arylaminoquinazoline derivatives with N,N-diethyl(aminoethyl)amino moiety were designed, synthesised and evaluated on biological activities in vitro. All synthesised compounds have inhibitory effects against tumour cells (SW480, A549, A431 and NCI-H1975). In particular, 4-(3-chloro-4-(3-fluorobenzyloxy)phenylamino)-6-(5-((N,N-diethyl(aminoethyl))aminomethyl)furan-2-yl)quinazoline (6a) and 6-(5-((N,N-diethylethyl)aminomethyl)furan-2-yl)-4-(4-(E)-(propen-1-yl)phenylamino)quinazoline (6d) were potent antitumour agents which showed high antiproliferative activities against tumour cells in vitro. Moreover, compound 6a could induce late apoptosis of A549 cells at high concentrations and arrest cell cycle of A549 cells in the G0/G1 phase at tested concentrations. Also, compound 6a could inhibit the activity of wild type epidermal growth factor receptor tyrosine kinase (EGFRwt-TK) with IC50 value of 15.60 nM. Molecular docking showed that compound 6a formed three hydrogen bonds with EGFRwt-TK, while lapatinib formed only two hydrogen bonds with the receptor protein. It is believed that this work would be giving a reference for developing anti-cancer drugs targeted EGFR-TK. [ABSTRACT FROM AUTHOR]

We present a new charge trapping memory (CTM) device with the Au/Ga2O3/SiO2/Si structure, which is fabricated by using the magnetron sputtering, high-temperature annealing, and vacuum evaporation techniques. Transmission electron microscopy diagrams show that the thickness of the SiO2 tunneling layer can be controlled by the annealing temperature. When the devices are annealed at 760 °C, the measured C–V hysteresis curves exhibit a maximum 6 V memory window under a ±13 V sweeping voltage. In addition, a slight degradation of the device voltage and capacitance indicates the robust retention properties of flat-band voltage and high/low state capacitance. These distinctive advantages are attributed to oxygen vacancies and inter-diffusion layers, which play a critical role in the charge trapping process. [ABSTRACT FROM AUTHOR]

Silk fibroin (SF), a natural polymer material possessing excellent biocompatibility and biodegradability, and has been widely used in biomedical applications. In order to explore the behavior of vascular cells by co-culturing on regenerated SF matrix for use as artificial blood vessels, human aorta vascular smooth muscle cells (HAVSMCs) were co-cultured with human arterial fibroblasts (HAFs) or human umbilical vein endothelial cells (HUVECs) on SF films and SF tubular scaffolds (SFTSs). Analysis of cell morphology and deoxyribonucleic acid (DNA) content showed that HUVECs, HAVSMCs and HAFs adhered and spread well, and exhibited high proliferative activity whether cultured alone or in co-culture. Immunofluorescence and scanning electron microscopy (SEM) analysis showed that HUVECs and HAFs co-existed well with HAVSMCs on SF films or SFTSs. Cytokine expression determined by reverse transcription-polymerase chain reaction (RT-PCR) indicated that the expression levels of α-smooth muscle actin (α-SMA) and smooth muscle myosin heavy chain (SM-MHC) in HAVSMCs were inhibited on SF films or SFTSs, but expression could be obviously promoted by co-culture with HUVECs or HAFs, especially that of SM-MHC. On SF films, the expression of vascular endothelial growth factor (VEGF) and platelet endothelial cell adhesion molecule-1 (CD31) in HUVECs was promoted, and the expression levels of both increased obviously when co-cultured with HAVSMCs, with the expression levels of VEGF increasing with increasing incubation time. The expression levels of VEGF and CD31 in cells co-cultured on SFTSs improved significantly from day 3 compared with the mono-culture group. These results were beneficial to the mechanism analysis on vascular cell colonization and vascular tissue repair after in vivo transplantation of SFTSs. [ABSTRACT FROM AUTHOR]

A silk fibroin tubular scaffold (SFTS) has been designed and fabricated using silk fabric and regenerated silk fibroin, and used in the construction of artificial blood vessels. As a replacement for blood vessels, scaffolds should have a suitable interface for the adherence and proliferation of vascular cells, and the pore structure of the internal surface is one of most important factors. In this article, we investigate the effect of SFTSs with different pore structures on cells growth. Pore structures were controlled by adjusting the concentration of both the silk fibroin and the polyethylene glycol diglycidyl ether cross-linker as well as the freezing temperature. Intuitive cell fluorescence imaging and MTT assays on fibroblasts and human umbilical vein endothelial cells (HUVEC) were used to probe interactions with internal surfaces of differing pore diameter and density. The results showed that SFTSs fabricated under different conditions exhibited no cytotoxicity. Furthermore, fibroblasts were highly migratory, occupied the interface and could bridge the macropores well when the pore diameter was 50 ∼ 75 µm. SFTSs with micropores of about 30 ∼ 50 µm in diameter were deemed suitable for the growth and proliferation of HUVECs. [ABSTRACT FROM AUTHOR]

Hirudin (Hir), a thrombin direct inhibitor, was used to modify a polyethylene glycol diglycidyl ether (PEG-DE) crosslinked regenerated silk fibroin (SF) material to improve hemocompatibility. Hemolysis characteristics, platelet adhesion, platelet activity, and plasma recalcification time were investigated using absorption spectrometry, scanning electron microscopy, MTT analysis, and the time counting method. Hirudin could be grafted evenly to the silk fibroin, and the modified material was resistant to hemolysis at ratios of less than 0.5%. Scanning electron microscopy and MTT results showed that platelet adhesion and aggregation activity decreased after modificaton with trace amounts of hirudin, compared with PEG-DE crosslinked and ethanol-treated silk fibroin film. Plasma recalcification of PEG-DE crosslinked silk fibroin film was slower than with ethanol-treated material, and this increased slightly after hirudin modification. Furthermore, L929, HAVSMC, and HUVEC cells adhered to the modified material, grew well, and possessed high proliferation activity on SF/Hir blend films. This study suggests that hirudin could improve the anticoagulation properties of regenerated silk fibroin materials. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 103B: 556-562, 2015. [ABSTRACT FROM AUTHOR]

Background: The use of contrast-enhanced ultrasound (CEUS) to locate sentinel lymph nodes (SLNs) in breast cancer has been studied more and more in recent years. This prospective study aimed to compare periareolar injection of two different contrast agents, SonoVue ® (SNV) and Sonazoid ® (SNZ), followed by CEUS to identify SLNs in breast cancer patients with clinically negative nodes., Methods: A total of 205 patients with T1-2N0M0 breast cancer were divided into the SNV group and SNZ group. All were administered a periareolar injection of SNV or SNZ and underwent US to identify contrast-enhanced SLNs. Each contrast-enhanced SLN underwent a biopsy with blue dye and examined again by CEUS in vitro ., Results: In all cases, contrast-enhanced lymphatic vessels were clearly visualized using US soon after the periareolar injection of SNZ, and the SLNs were easily identified. The SLN identification rates were 75.27% (210/279) for SNV and 93.58% (102/109) for SNZ. Although the accuracy of detecting SLN metastasis was slightly different between the two groups, there was no statistically significant difference between those groups (P=0.615). Moreover, it was possible to identify SLNs in vitro in the SNZ group, and these could be compared with the lymph nodes (LNs) located using SNZ during the preoperative stage and with blue dye during the procedure. This helped in determining the resection requirements., Conclusions: When comparing the subdermal use of SNV and SNZ, no significant differences in the number of detected SLNs and the diagnosis of metastatic LNs were observed. Because SLNs can be detected for a longer time in living tissues with SNZ, this contrast agent may provide more intraoperative information for complete resection of all preoperative localization of SLN., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at http://dx.doi.org/10.21037/gs-21-87). The authors have no conflicts of interest to declare., (2021 Gland Surgery. All rights reserved.)

Herein, four novel 4-arylaminoquinazoline derivatives with N , N -diethyl(aminoethyl)amino moiety were designed, synthesised and evaluated on biological activities in vitro . All synthesised compounds have inhibitory effects against tumour cells (SW480, A549, A431 and NCI-H1975). In particular, 4-(3-chloro-4-(3-fluorobenzyloxy)phenylamino)-6-(5-(( N , N -diethyl(aminoethyl))aminomethyl)furan-2-yl)quinazoline ( 6a ) and 6-(5-(( N , N -diethylethyl)aminomethyl)furan-2-yl)-4-(4-( E )-(propen-1-yl)phenylamino)quinazoline ( 6d ) were potent antitumour agents which showed high antiproliferative activities against tumour cells in vitro . Moreover, compound 6a could induce late apoptosis of A549 cells at high concentrations and arrest cell cycle of A549 cells in the G0/G1 phase at tested concentrations. Also, compound 6a could inhibit the activity of wild type epidermal growth factor receptor tyrosine kinase (EGFR wt -TK) with IC 50 value of 15.60 nM. Molecular docking showed that compound 6a formed three hydrogen bonds with EGFR wt -TK, while lapatinib formed only two hydrogen bonds with the receptor protein. It is believed that this work would be giving a reference for developing anti-cancer drugs targeted EGFR-TK.