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AbstractMonitoring large gradient ground deformation due to temporal and spatial image decoherence has long been a challenge. We attempted an improvement using Sentinel-1A and Sentinel-1B C-band data fusion methods based on the variation law of subsidence velocity of ground leveling monitoring points. This approach improved the temporal resolution from 12 to 6 days. Using a mine in Datong, Shanxi Province, China as an example, 13 scenes of Sentinel-1A data and 12 scenes of Sentinel-1B data were fused and compared with ground-measured data. The results obtained were closer to the measured values than those obtained by single data set (Sentinel-1A or -1B only). Simultaneously, 61 scenes of Sentinel-1A data and 12 scenes of Sentinel-1B data were used to calculate the subsidence of the mining area over two years. The subsidence map was consistent with the actual leveling trend, which reflected the dynamic change of surface subsidence range in the mining area. This study provides an approach using DInSAR technology to monitor large gradient deformation in mining areas and provides an effective method to monitor of surface dynamic deformation.

The use of biomaterials for circumferential esophageal repair is technically challenging in a rat model, and an optimal scaffold implantation technique with nutritional support is essential. The purpose of this study was to investigate the effects of three-dimensional printed esophageal grafts and bioreactor cultivation on muscle regeneration and reepithelialization from circumferential esophageal defects in a rat model. Here, we designed an artificial esophagus that can enhance the regeneration of esophageal mucosa and muscle through the optimal combination of a two-layered tubular scaffold and mesenchymal stem cell-based bioreactor system. The graft was verified by the performance comparison with an omentum-cultured esophageal scaffold. We also applied a new surgical anastomosis technique and a thyroid gland flap over the implanted scaffold to improve graft survival. Although no regenerated mucosal layer was observed around the implants of the control group, histological examination of the regenerative esophagi along the scaffold revealed that the bioreactor system and omentum-cultured groups showed more than 80% of the mucosal regeneration without a fistula. The regenerated tissues showed that the integration of the esophageal scaffold and its native esophageal tissue was intact and were covered with layers of stratified squamous epithelium with several newly developed blood vessels. Therefore, this study describes a novel approach for circumferential esophageal reconstruction.Impact StatementIn vivofunctional esophageal reconstruction remains challenging due to anastomosis site leakage and necrosis of the implanted scaffold in a circumferential esophageal defect. Therefore, it is necessary to develop a tissue-engineered esophagus that enables regeneration of esophageal mucosa and muscle without leakage of the esophageal anastomosis. In this study, we proposed an intriguing strategy that combines a mesenchymal stem cell-seeded tubular scaffold with a bioreactor system for esophageal reconstruction and introduced a new surgical anastomosis technique with the thyroid gland flap over the implanted scaffold to improve graft survival. We believe that this system should be a powerful platform for circumferential replacement of the esophagus in a rat model.

This study aims to investigate the roles and effects of EGCG (epigallocatechin-3-gallate) during the osteogenic differentiation of human mesenchymal stem cells (hMSCs) in vitro. Recent studies have shown that proper mechanical stimuli can induce osteogenic differentiation of hMSCs apart from biochemical factors. In this study, the hMSC cultures were subjected to: (1) 25 uM EGCG alone or (2) 3% mechanical stretching (0.2 Hz for 4 h/day for 4 days) or (3) in combination with 3% mechanical stretching (0.2 Hz for 4 h/day for 4 days). The two factors were applied to the cell cultures separately and in combination to investigate the individual and synergistic effect of both mechanical stimulation and ECGC in the osteogenic differentiation of hMSCs. Utilizing real time PCR, we measured various osteogenic markers and even those related to intracellular signalings. Further investigation of mitochondria was performed that mitochondria biogenesis, antioxidant capacity, and morphological related markers were measured. hMSCs were to be osteogenic or myogenic differentiated when they were under 3% stretching only. However, when EGCG was applied along with stretching they were to be osteogenic differentiated rather than to be myogenic differentiated. This was supported by evaluating intracellular signalings: BMP-2 and VEGF. Therefore, the synergistical effects of simultaneous employment of stretching and EGCG on osteogenic differentiation were confirmed. Moreover, simultaneous employment was found positive in mitochondria biogenesis, antioxidant capacity, and morphological changes. Through this study, we came into the conclusion that the combination of proper mechanical stretching, 3% in this study, and EGCG promote osteogenic differentiation. Reflecting that EGCG can be obtained from plants not from the chemical syntheses, it is worth to be studied further either by animal tests or long-term experiments for clinical applications.

Tendon and ligament (T/L) have been known to be obviously different from each other in tissue level. However, due to the overlapping gene markers, distinction in cellular level has not been clearly verified yet. Recently, the use of nuclear magnetic resonance (NMR) spectroscopy has shown the potential to detect biological markers in cellular level. Therefore, in this study we applied a non-invasive technique based on NMR spectroscopy to establish biomarkers to distinguish between T/L fibroblasts. In addition the cellular morphologies and gene expression patterns were also investigated for comparison through optical microscopy and real-time polymerase chain reaction (PCR). No difference was observed from morphology and real-time PCR results, either as expected. However, we found clear differences in their metabolomic spectra using 1H NMR spectroscopy. The calculated integral values of fatty acids (with chemical shifts at ~0.9, 1.26, 1.59, 2.05, 2.25, and 2.81 ppm), lactate (~1.33 ppm), and leucine (~2.72 ppm) were significantly different between the two types of fibroblasts. To be specific tendon group exhibited higher level of the metabolite than ligament group. In conclusion, in-cell metabolomic evaluation by NMR technique used in this study is believed to provide a promising tool in distinguishing cell types, especially T/L cells, which cannot be classified by conventional biological assays.

Sirtuin 6 (SIRT6) is a NAD‐dependent deacetylase involved in lifespan regulation. To evaluate the effect of SIRT6 on osteogenesis, rat bone marrow mesenchymal stem cells (rBMSCs) with enhanced or reduced SIRT6 function were developed. We observed that SIRT6 knockdown significantly reduced the mRNA levels of several key osteogenic markers in vitro, including alkaline phosphatase (ALP), Runt‐related transcription factor 2 (RUNX2), and osteocalcin, while overexpression of SIRT6 enhanced their expression. Additionally, SIRT6 knockdown activated nuclear factor‐κB (NF‐κB) transcriptional activity and upregulated the expression of acetyl‐NF‐κB p65 (Lys310). The decreased osteogenic differentiation ability of rBMSCs could be partially rescued by the addition of NF‐κB inhibitor BAY 11–7082. Furthermore, SIRT6 overexpression in rBMSCs combined with the use of collagen/chitosan/hydroxyapatite scaffold could significantly boost new bone formation in rat cranial critical‐sized defects, as determined by microcomputed tomography and histological examination. These data confirm that SIRT6 is mainly located in the nuclei of rBMSCs and plays an essential role in their normal osteogenic differentiation, partly by suppressing NF‐κB signaling. StemCells2014;32:1943–1955

Lithium-doped strontium fluoride crystals were successfully colored electrolytically, and a lot of F, M (F2), M+ (F2+) and unidentified color centers were effectively produced in the colored crystals, which should mainly benefit from the appropriate impurity doped in the crystals, coloration temperature and electric field strength.

AbstractChina is among the twelve megadiversity countries in the world and one of the two countries with the highest biodiversity and endemism in Asia and South‐Pacific region. China has the highest mountain system of the world and different types of environments inhabited by living organisms, ranging from the Palaearctic to Oriental Realms. These characteristics account for the magnificent species diversity and high level of endemism. Insects of 45 000 species have been recorded in China by now. The total endemic elements are obviously much more than the neighbouring countries. Especially in the south‐west mountainous region and tropical areas the endemic elements occupy high proportions. The human disturbances, original habitat losses due to reclamation, deforestation, pollution, etc., are driving undetermined number of species to be endangered or extinct. Recommendations of China's insect conservation are hereon presented: identifying conservation priorities, investigating the biology and ecology of endangered species, monitoring habitat and diversity losses, compiling the “Red List” and the database of rare and endangered species, establishing reserves for insect conservation, and developing techniques of insect farming and ranching.