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An event-triggered adaptive control algorithm is proposed for cooperative tracking control of high-order nonlinear multi-agent systems (MASs) with prescribed performance and full-state constraints. The algorithm combines dynamic surface technology and the backstepping recursive design method, with radial basis function neural networks (RBFNNs) used to approximate the unknown nonlinearity. The barrier Lyapunov function and finite-time stability theory are employed to prove that all agent states are semi-globally uniform and ultimately bounded, with the tracking error converging to a bounded neighborhood of zero in a finite time. Numerical simulations are provided to demonstrate the effectiveness of the proposed control scheme.

This paper presents an adaptive neural network controller based on a disturbance observer to compensate the disturbance caused by neural network approximation for a class of unknown nonlinear systems. The proposed adaptive neural network control with an updated parameters mechanism is not subject to the restriction of compact set assumption for satisfying the universal approximation property. The neural network approximation error can be compensated online through the proposed disturbance observer. The proposed method eliminates the need to obtain an exact system model before applying the ideal controller. The effectiveness of the proposed method is validated by numerical simulations. [ABSTRACT FROM AUTHOR]

Objective: Osteogenesis is a multiple‐step process through which osteoblasts are derived from bone marrow mesenchymal stem cells (MSCs) with multilineage differentiation potential. This study aimed to analyze gene expression profiling during osteogenic differentiation of MSCs. Materials and Methods: Human MSCs were isolated and induced for differentiation in osteogenic medium. Full‐genome gene expression microarrays and gene ontology analysis were performed. Results: A total of 1,680 differentially expressed genes in differentiated MSCs were identified including 430 upregulated and 1,250 downregulated. Moreover, pathway‐act‐network analysis showed that cell cycle, p53 signaling pathway and focal adhesion, had high degree (>5). The ribonucleotide reductase M1, thymidine kinase 1 and histone cluster 1 H3e also showed high degree (>10). Polymerase chain reaction analysis confirmed the differential expression of insulin‐like growth factor binding protein 3, SMAD family member 3, transforming growth factor beta 2, and fibroblast growth factor 14 in differentiated MSCs. Conclusions: Gene expression profiling provides a foundation to reveal the mechanisms that regulate osteogenic differentiation of MSCs. We applied microarray and bioinformatics technology to perform gene expression profiling of human bone marrow mesenchymal stem cells during osteogenic differentiation. Our findings of the differential genes and significant pathways provide new insight into osteogenic differentiation of hMSC. [ABSTRACT FROM AUTHOR]

Background: Supramolecular micelles as drug-delivery vehicles are generally unable to enter the nucleus of nondividing cells. In the work reported here, nuclear localization signal (NLS)-modified polymeric micelles were studied with the aim of improving nuclear drug delivery., Methods: In this research, cholesterol-modified glycol chitosan (CHGC) was synthesized. NLS-conjugated CHGC (NCHGC) was synthesized and characterized using proton nuclear magnetic resonance spectroscopy, dynamic light scattering, and fluorescence spectroscopy. Doxorubicin (DOX), an anticancer drug with an intracellular site of action in the nucleus, was chosen as a model drug. DOX-loaded micelles were prepared by an emulsion/solvent evaporation method. The cellular uptake of different DOX formulations was analyzed by flow cytometry and confocal laser scanning microscopy. The cytotoxicity of blank micelles, free DOX, and DOX-loaded micelles in vitro was investigated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay in HeLa and HepG2 cells., Results: The degree of substitution was 5.9 cholesterol and 3.8 NLS groups per 100 sugar residues of the NCHGC conjugate. The critical aggregation concentration of the NCHGC micelles in aqueous solution was 0.0209 mg/mL. The DOX-loaded NCHGC (DNCHGC) micelles were observed as being almost spherical in shape under transmission electron microscopy, and the size was determined as 248 nm by dynamic light scattering. The DOX-loading content of the DNCHGC micelles was 10.1%. The DOX-loaded micelles showed slow drug-release behavior within 72 hours in vitro. The DNCHGC micelles exhibited greater cellular uptake and higher amounts of DOX in the nuclei of HeLa cells than free DOX and DOX-loaded CHGC (DCHGC) micelles. The half maximal inhibitory concentration (IC(50)) values of free DOX, DCHGC, and DNCHGC micelles against HepG2 cells were 4.063, 0.591, and 0.171 μg/mL, respectively. Moreover, the IC(50) values of free DOX (3.210 μg/mL) and the DCHGC micelles (1.413 μg/mL) against HeLa cells were nearly 6.96- and 3.07-fold (P < 0.01), respectively, higher than the IC(50) value of the DNCHGC micelles (0.461 μg/mL)., Conclusion: The results of this study suggest that novel NCHGC micelles could be a potential carrier for nucleus-targeting delivery.

Summary: To comparatively investigate ultrastructural characteristics and expressions of AFP (alpha-fetoprotein) and Tn (Thomsen-Friedenreich-related antigen) protein in AFP negative (AFP-) and AFP positive (AFP+) primary hepatocellular carcinoma. Fourty-three cases of AFP- and AFP+ hepatocellular carcinoma (HCC) tissues and five cases of normal liver tissues were divided into three groups: control group (normal liver tissue, n=5); AFP+ HCC group (the serum AFP level was higher than 10 ng/ml, n = 22); AFP- HCC group (the serum AFP level was lower than 10 ng/ml, n=21). The ultrastructural morphology was studied by transmission electron microscopy, the expressions of AFP and Tn protein were detected by immunohistochemistry and cell image analysis. 1. The immunohistochemical study showed that (1) the expression intensity and positive rate of Tn protein in AFP- HCC group were markedly higher than that in AFP+ HCC group (P<0.01); (2) The expression intensity of AFP in AFP- HCC group was lower than that in AFP+ HCC group (P<0.01). 2. The transmission electron microscopy demonstrated that some AFP- HCC cells linked closely with each other, others dispersed loosely just as cultured cells, the remarkable morphologic features in AFP- HCC cells were simple organelles, but they were abundant in the free polyribosomes. In AFP+ HCC group, all the HCC cells linked closely together and were rich organelles in their cytoplasm, especially the rough endoplasmic reticula. In addition, mitochondria and Golgi complex were obviously observed. (1) The AFP and Tn protein had discrepancy distribution in AFP- and AFP+ HCC tissues, Tn protein may be one of the early diagnostic indicators in AFP- HCC; (2) The synthetic locations of the AFP and Tn protein were different in hepatocarcinoma cells by ultrastructural observation.