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Background: The purpose of this study was to test effects of negative pressure on tendon--bone healing after reconstruction of anterior cruciate ligament (ACL) in rabbits. Methods: Hind legs of 24 New Zealand White rabbits were randomly selected as negative pressure group and the contralateral hind legs as control. Reconstruction of the ACL was done. Joints of the negative pressure side were placed with drainage tubes connecting the micro-negative pressure aspirator. Control side was placed with ordinary drainage tubes. Drainage tubes on both sides were removed at the same time 5 days after operation. After 6 weeks, joint fluid was drawn to detect the expression levels of interleukin-1β (IL-1β)andtumornecrosisfactor-α (TNF-α); at the same time, femur--ligament--tibia complex was obtained to determine tendon graft tension and to observe the histomorphology, blood vessels of the tendon--bone interface, and expression of vascular endothelial growth factor (VEGF). Results: The maximum load breakage of tendon graft was significantly greater in the negative pressure group than in the control group (P < 0.05). Histological studies of the tendon--bone interface found that there was more new bone formation containing chondroid cells and aligned connective tissue in the negative pressure group than in the control group. Expression of VEGF was higher in the negative pressure group than in the control group (P <0.01).Contentof IL-1β and TNF-α in synovial fluid is lower in the negative pressure group than in the control group (P <0.01). Conclusions: Intermittent negative pressure plays an active role in tendon--bone healing and creeping substitution of ACL reconstruction in the rabbits. [ABSTRACT FROM AUTHOR]

As an invited paper with the designated title to this focused session, this is to introduce the pulse discharge sintering process applied for the sintering and/or synthesis of a few representative MAX phases, such as TiSiC, TiAlC, TiAlC, TiAlN, CrAlC, CrGaC, TiGaC, as well as the MAX-based solid solutions and some composites. The effects of processing parameters on the synthesis reactions, densification, microstructure, as well as the properties have been investigated. This paper not only briefly reviews our synthesis work on the MAX phases but also presents new results such as the comparison of PDS with conventional hot pressing, the newly obtained results on the synthesis of CrGaC, TiGaC, as well as some solid solutions and composites. With the results presented herein as summarized in tables and figures, none of which were published elsewhere, this article aims at a better understanding of the PDS process in the research and development of the MAX phases and related materials. [ABSTRACT FROM AUTHOR]

The objective of this study was to analyze gene expression profiles of intervertebral disc samples and peripheral blood mononuclear cells (PBMCs) from patients with degenerative discs using Agilent's Human 1A Oligo microarray. RNA samples from disc tissue and PBMCs were obtained from patients with degenerative discs and from subjects in a control group. RNA samples were reverse-transcribed into Cy5-labeled cRNA, combined with a Cy3-labeled reference and hybridized to oligonucleotide microarrays. Microarrays were scanned by Gene-Pix 4000B and data were analyzed using GenePixPro 3.0 software. The microarray data were validated in the same RNA samples by qRT-PCR analysis of selected genes. For the disc tissue, the mRNA expressions of 522 genes changed obviously in the degeneration group, accounting for approximately 2.64% of all analyzed transcripts. These included transcription-related, ion channel and transport protein, receptor, protein synthesis and modifying, growth factor, etc. For PBMCs, the expressions of 62 genes changed obviously in the patients in the degeneration group. These changes included ion channel, transport protein, transcription-related, DNA synthesis and repair, metalloprotease, immune globulin-related, growth factor-related, extracellular matrix-related, adhesion molecule, etc. Analyzed on the association of the differential expression of genes between disc tissue and PBMCs, some genes were not compatible. The course of intervertebral disc denegation is a complicated dynamic process, however, and may mainly be local pathogenesis. These findings furnish new data for the mechanistic investigation of degenerative discs. [ABSTRACT FROM AUTHOR]

To modify the adsorption performance of Ti 3 C 2 T x MXene, we report a facile approach to expand the interlayer spacing of Ti 3 C 2 T x and to tune its surface functional groups by hot alkaline solution treatment. In the treatment, the interlayer spacing of Ti 3 C 2 T x MXene is increased by up to 29% by LiOH, and the surface functional groups are tuned by converting -F to -OH. Among the MXenes, LiOH-Ti 3 C 2 T x and NaOH-Ti 3 C 2 T x can faster adsorb methylene blue (MB) than other MXene adsorbents; NaOH-Ti 3 C 2 T x possesses the highest adsorption capacity (189 mg/g) for MB, which can be ascribed to the cooperation of surface adsorption and intercalation adsorption. The experimental data suggest that the enhanced adsorption toward cationic dyes can be best described by a Langmuir isotherm. [ABSTRACT FROM AUTHOR]

Diamond growth on polycrystalline Ti3SiC2was investigated using microwave plasma chemical vapour deposition (MPCVD) under typical microcrystalline diamond growth conditions. Scanning electron microscopy (SEM), atomic force microscopy (AFM), Raman spectroscopy and synchrotron near edge extended x-ray absorption fine structure spectroscopy (NEXAFS) were used to characterize the synthesized films. A diamond nucleation density of 1011cm?2has been achieved and consequently, dense nanocrystalline diamond (NCD) thin films with an average grain size of approximately 30 nm and a film growth rate of approximately 2 µm h?1were synthesized. The NEXAFS spectra of the NCD films exhibit clear spectral characteristics of natural diamond with a weak peak of sp2carbon. Cross-sectional SEM images show that the NCD films have an equiaxed grain structure and a dense film/substrate interface. [ABSTRACT FROM AUTHOR]