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This article presents a new family of kinematically redundant parallel mechanisms (KR-PMs) with two rotations and one translation (2R1T) based on the Lie group method. Compared with the 2-UPR/RPU PM, these PMs have two main advantages, namely, larger reachable workspaces of the moving platforms and higher motion/force transmission performance, as verified by three typical cases. The inverse kinematics, velocities, singularities, and workspaces of the 2-UPR/PRPU PM are analyzed in detail. A new method for motion/force transmission performance evaluation of KR-PMs in accordance with the indices for nonredundant PMs is proposed. Moreover, the local and global motion/force transmission performances of the 2-UPR/PRPU PM are determined using the new method. [ABSTRACT FROM AUTHOR]

This article presents a new family of kinematically redundant parallel mechanisms (KR-PMs) with two rotations and one translation (2R1T) based on the Lie group method. Compared with the 2-UPR/RPU PM, these PMs have two main advantages, namely, larger reachable workspaces of the moving platforms and higher motion/force transmission performance, as verified by three typical cases. The inverse kinematics, velocities, singularities, and workspaces of the 2-UPR/PRPU PM are analyzed in detail. A new method for motion/force transmission performance evaluation of KR-PMs in accordance with the indices for nonredundant PMs is proposed. Moreover, the local and global motion/force transmission performances of the 2-UPR/PRPU PM are determined using the new method. [ABSTRACT FROM AUTHOR]

Kinematic calibration is commonly used to improve the accuracy of a parallel mechanism. This paper presents an effective method for calibrating an overconstrained three degrees-of-freedom parallel manipulator employing a direct kinematic model. An error-mapping function is formulated from the differential of its kinematic model which is established through vector chains with the geometrical errors. To simplify the measurement of the error, the positioning and orientation error of the moving platform is replaced by the positioning error of the tool center point, which can be measured by a laser tracker accurately. Three different objective functions F1, F2, and F∞, respectively, representing 1-norm, 2-norm, and inf-norm of the error vector are used to identify the geometrical parameters of the manipulator. The results of computer simulation show that parameters after kinematic calibration through minimizing the objective function F2 is highly accurate and efficient. A calibration experiment is carried out to verify the effectiveness of the method. The maximum residual of calibration points reduces greatly from 3.904 to 0.256 mm during parameter identification. The positioning errors of all points on and inside the space surrounded by the calibration points are smaller than 0.4 mm after error compensation. [ABSTRACT FROM AUTHOR]

Background: Lung cancer, predominantly non-small-cell lung cancer (NSCLC), is the leading cause of cancer deaths worldwide. There is a great need to identify critical effectors involved in metastasis of NSCLC that will facilitate the development of new therapeutic strategies. Here we evaluated the potential role of miR-125b in the metastasis of NSCLC cells. Methods: Human NSCLC cells were isolated from surgical tissues with Cancer Cell Isolation Kit. Expressions of miR- 125b and TP53INP1 were detected with real-time PCR and western blot. Human miR-125b mimics, miR-125b inhibitor, TP53INP1 expression plasmid and TP53INP1 siRNA were transfected into NSCLC cells with nucleofector transfection kit. NSCLC metastasis was determined with adhesion assay, invasive assay and lung tumor metastasis model. Results: The expression of miR-125b was significantly higher in poorly differentiated NSCLC cells that are endowed with high metastatic potentials. Up-regulation of miR-125b could enhance the metastatic potential of NSCLC cells in vitro and in vivo, while down-regulation of miR-125b resulted in decreased metastatic potentials in vitro and in vivo. Further, tumor protein 53-induced nuclear protein 1 (TP53INP1) was an important target of miR-125b involved in metastasis of NSCLC cells. TP53INP1 served as a negative regulator of NSCLC metastasis. Decreased expression of TP53INP1 in tumor tissues was inversely associated with their expression of miR-125b, significantly lower in poorly differentiated tumors and inversely correlated with the clinical stages in patients with NSCLC. Conclusions: These findings demonstrated that miR-125b promoted tumor metastasis via targeting TP53INP1 in human NSCLC cells, which uncovered a real clinical relevance of microRNAs in tumor biology, and provided novel potential candidates for NSCLC clinical practice. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the regulatory mechanisms underlying sepsis progression in patients with tumor necrosis factor (TNF)-α genetic variations. The GSE5760 expression profile data, which was downloaded from the Gene Expression Omnibus database, contained 30 wild-type (WT) and 28 mutation (MUT) samples. Differentially expressed genes (DEGs) between the two types of samples were identified using the Student's t-test, and the corresponding microRNAs (miRNAs) were screened using WebGestalt software. An integrated miRNA-DEG network was constructed using the Cytoscape software, based on the interactions between the DEGs, as identified using the Search Tool for the Retrieval of Interacting Genes/Proteins database, and the correlation between miRNAs and their target genes. Furthermore, Gene Ontology and pathway enrichment analyses were conducted for the DEGs using the Database for Annotation, Visualization and Integrated Discovery and the KEGG Orthology Based Annotation System, respectively. A total of 390 DEGS between the WT and MUT samples, along with 11-associated miRNAs, were identified. The integrated miRNA-DEG network consisted of 38 DEGs and 11 miRNAs. Within this network, COPS2 was found to be associated with transcriptional functions, while FUS was found to be involved in mRNA metabolic processes. Other DEGs, including FBXW7 and CUL3, were enriched in the ubiquitin-mediated proteolysis pathway. In addition, miR-15 was predicted to target COPS2 and CUL3. The results of the present study suggested that COPS2, FUS, FBXW7 and CUL3 may be associated with sepsis in patients with TNF-α genetic variations. In the progression of sepsis, FBXW7 and CUL3 may participate in the ubiquitin-mediated proteolysis pathway, whereas COPS2 may regulate the phosphorylation and ubiquitination of the FUS protein. Furthermore, COPS2 and CUL3 may be novel targets of miR.15. [ABSTRACT FROM AUTHOR]

Study Design: This is a bioinformatic study designed to investigate the time-course expression changes of microRNAs (miRNAs) after spinal cord injury (SCI).Objective: To investigate the mechanism of SCI self-repair at miRNAs level and target genes level.Summary Of Background Data: SCI results in loss of sensory and locomotor function, and SCI self-repair might provide clinical therapies; however, the mechanism of SCI self-repair remains unclear.Methods: The miRNA expression profile (GSE19890) of adult female Wistar brown rats (Rattus norvegicus) in SCI (laminectony and contusion), sham (laminectony but no contusion), and control (untreated) groups was downloaded from Gene Expression Omnibus. Totally, 35 chips were available, including five controls, five SCI-1-day, five SCI-3-day, five SCI-7-day, five sham-1-day, five sham-3-day, and five sham-7-day. Betr and limma package were used to screen time-course differentially expressed miRNAs (DEmiRNAs), followed by Bayesian hierarchical clustering (BHC), synergetic and functional enrichment analysis through BHC and cluster Profiler packages, respectively. Furthermore, STRING database and Cytoscape software were used to construct interaction networks between time-course DEmiRNAs, and GenCLip2.0 software was applied to pathway enrichment for key genes associated with nervous system.Results: Totally, 68 time-course DEmiRNAs were identified and divided into 15 BHC clusters. Then, 100 time-course DEmiRNA pairs with synergetic function were identified, and time-course DEmiRNAs and target genes interaction networks were constructed, in which 10 genes (AKT1, VEGFA, CTNNB1, IGF1, APP, PTEN, CDC42, BDNF, SOD2, and IFNG) with highest degrees were found. Furthermore, key genes were significantly enriched in neurotrophin signaling pathway.Conclusion: After SCI, miRNAs might collectively regulate target genes, facilitating or inhibiting self-repair. Modulation of these miRNAs might provide novel therapies for SCI treatment.Level Of Evidence: N/A. [ABSTRACT FROM AUTHOR]

Background: The study aimed to investigate the expression changes of genes in colorectal cancer (CRC) and screen the potential molecular targets. Methods: The GSE37178 of mRNA expression profile including the CRC samples extracted by surgical resection and the paired normal samples was downloaded from Gene Expression Omnibus database. The genes whose expressions were changed at four different time points were screened and clustered using Mfuzz package. Then DAVID was used to perform the functional and pathway enrichment analysis for genes in different clusters. The protein-protein interaction (PPI) networks were constructed for genes in the clusters according to the STRING database. Furthermore, the related-transcription factors (TFs) and microRNAs (miRNAs) were obtained based on the resources in databases and then were combined with the PPI networks in each cluster to construct the integrated network containing genes, TFs and miRNAs. Results: As a result, 314 genes were clustered into four groups. Genes in cluster 1 and cluster 2 showed a decreasing trend, while genes in cluster 3 and cluster 4 presented an increasing trend. Then 18 TFs (e.g., TCF4, MEF2C and FOS) and 18 miRNAs (e.g., miR-382, miR-217, miR-1184, miR-326 and miR-330-5p) were identified and three integrated networks for cluster 1, 3, and 4 were constructed. Conclusions: The results implied that expression of PITX2, VSNL1, TCF4, MEF2C and FOS are time-related and associated with CRC development, accompanied by several miRNAs including miR-382, miR-217, miR-21, miR-1184, miR- 326 and miR-330-5p. All of them might be used as potential diagnostic or therapeutic target molecules for CRC. [ABSTRACT FROM AUTHOR]