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This review describes the classification of hydrogels, the methods of production of decellularised extracellular matrix (dECM) and the methods of gel formation. Finally, the role of dECM hydrogels in the treatment of intervertebral disc degeneration is summarized.

Lower back pain (LBP) is one of the most common musculoskeletal complaints worldwide. Intervertebral disc degeneration (IDD) is considered to be a significant contributor to LBP; however, the mechanisms underlying IDD remain to be fully elucidated. One of the major features of IDD is the decreased content of type II collagen and proteoglycans in the nucleus pulposus (NP). The present study aimed to investigate the biochemical mechanisms of IDD at the microscopic level using Raman spectroscopy. Raman spectroscopy, based on inelastic scattering of light, is an emerging optical technique that may measure the chemical composition of complex biological samples, including biofluids, cells and tissues. In the present study, 30 NP tissue samples from 30 patients who were diagnosed with lumbar disc herniation and received spinal fusion surgery to relieve LBP were obtained and analyzed. Routine pre-operative 3.0T, T2-weighed MRI was used to classify the cases according to Pfirrmann grades and the T2 signal intensity value of the NP was measured. Subsequently, all NP samples were scanned and analyzed using a Laser MicroRaman Spectrometer at room temperature. The Raman spectral results demonstrated that the relative content of proteoglycans, expressed as the relative intensity ratio of two peaks (I1064/I1004), was significantly inversely correlated with the Pfirrmann grade (ρ=-0.6462; P

Purpose of the article: To investigate the correlation between C7 slope and cervical lordosis in patients after expansive open-door laminoplasty (EOLP).Material and methods: We retrospectively analyzed 57 patients who underwent EOLP between June 2013 and January 2017 in the Department of Spinal Surgery of our hospital. The operation time, intraoperative blood loss and follow-up time were recorded. The C7 slope, C2-7 sagittal vertical axis, and C2-7 Cobb angle were measured anteroposterior radiograph of the cervical spine preoperatively and postoperatively. All patients were divided into two groups according to the preoperative C7 slope (C7 slope ≤20° group and C7 slope >20° group).Results: The amount of intraoperative bleeding was 220.2 ± 180.9ml, and the operation time was 143.4 ± 51.2min. The average follow-up time was 24.9 ± 10.3months (range12-48 months). The C2-7 Cobb angle was 13.49 ± 10.46°at the final follow-up, which was significantly lower than that preoperatively (p = .026). But, The C7 slope and C2-7 sagittal vertical axis showed no significant difference between preoperatively and postoperatively. Preoperative and postoperative C7 slope and C2-7 Cobb angle were positively correlated to age and significant difference was observed. In the group of C7 slope >20°, significant difference was observed in term of the change of the C2-7 Cobb angle and C2-7SVA postoperatively (p = .009 and p= .020). However, there was no statistically significant difference detected in these two parameters in the group of C7 slope ≤20°.Conclusion: This study indicated that C7 slope could be used as an indicator of the change in the curvature of the cervical spine after EOLP. The loss of cervical curvature after surgery was prone to occur when C7 slope was greater than 20°, which should be noted in clinical practice.

Solar water evaporation is universally considered as an effective method to alleviate the freshwater shortage worldwide. A series of three-dimensional, salt-resistant evaporators have been brought out to improve the evaporation performance. However, little attention was paid to the collection of salt from seawater and high salinity brine. In this work, a carbon black polyvinyl alcohol (PVA) sponge was prepared to harvest light using a physical adsorption method to load carbon black on the PVA sponge. The experimental results showed that optimal light absorption (97.8%) and evaporation rate (1.60 kg m

Microchannels are effective means of enabling the functional performance of tissue engineering scaffolds. Chitosan, a partial deacetylation derivative of chitin, exhibiting excellent biocompatibility, has been widely used in clinical practice. However, development of chitosan scaffolds with controllable microchannels architecture remains an engineering challenge. Here, we generated chitosan scaffolds with adjustable microchannel by combining a 3D printing microfiber templates-leaching method and a freeze-drying method. We can precisely control the arrangement, diameter and density of microchannel within chitosan scaffolds. Moreover, the integrated bilayer scaffolds with the desired structural parameters in each layer were fabricated and exhibited no delamination. The flow rate and volume of the simulated fluid can be modulated by diverse channels architecture. Additionally, the microchannel structure promoted cell survival, proliferation and distribution in vitro, and improved cell and tissue ingrowth and vascular formation in vivo. This study opens a new road for constructing chitosan scaffolds, and can further extend their application scope across tissue engineering and regenerative medicine.

Constructing a biomimetic scaffold that replicates the complex architecture of intervertebral disc annulus fibrosus (AF) remains a major goal in AF tissue engineering. In this study, a biomimetic angle-ply multi-lamellar polycaprolactone/silk fibroin (PCL/SF) AF scaffold was fabricated. Wet-spinning was used to obtain aligned PCL/SF microfiber sheets, and these were excised into strips with microfibers aligned at +30° or -30° relative to the strip long axis. This was followed by stacking two strips with opposing fiber alignment and wrapping them concentrically around a mandrel. Our results demonstrated that the scaffold possessed spatial structure and mechanical properties comparable to natural AF. The scaffold supported rabbit AF cells adhesion, proliferation, infiltration and guided oriented growth and extracellular matrix deposition. In conclusion, our angle-ply multi-lamellar scaffold offers a potential solution for AF replacement therapy and warrants further attention in future investigations.

In order to explore the monitoring and control method of rock slope, indoor physical model testing of collapse control and monitoring were carried out with the example of a rock slope collapse area project in Jietai Temple in Beijing, China, as the prototype. Based on the similarity theory, in this study, a new structural support with Negative Poisson’s Ratio bolt and flexible anchored net was utilized to reinforce the rock slope. Following a graded loading sequence, the collapse failure characteristics and the overall control effect of energy absorption reinforcement measures were explored. The experimental results demonstrated that the entire process of slope collapse presented four distinct stages of failure: fracture generation, fracture propagation, partial collapse, and overall collapse. The full-field displacement nephogram and the displacement monitoring point of the collapse area indicated that the large deformation and failure of the collapsed surrounding rock were effectively controlled, while the Negative Poisson’s Ratio bolt and the flexible anchored net had good reinforcement effects. The experimental stress record presented that the change of pressure curve was an apparent regularity in the entire process of slope collapse, which reflects the change state of internal force of surrounding rock; it includes the function of monitoring of slope collapse. It was indicated that the Negative Poisson’s Ratio bolt along with the large-deformation flexible anchored net had good reinforcement monitoring effect on the rock slope collapse disaster.

Objective: This study was designed to see if neuregulin-1β (NRG-1β) plays a protective role in spinal cord ischemia and reperfusion injury (SCII). Design: Animal research. Setting: China. Participants: NA. Interventions: Forty-eight SD rats were randomly divided into control group (n = 16), SCII model group (n = 16) and NRG-1β-treated group (n = 16). In control group, the abdominal aorta was isolated but not clipped. The rats in NRG-1β-treated group were treated with 10μg/kg NRG-1β during developing SCII model. Outcome Measures: Neurological scores were evaluated. At 3, 6, 12 and 24 h after the reperfusion, rats were killed. Pathological changes of spinal cord were assessed with HE staining, and immunohistochemical staining of matrix metalloproteinases-9 (MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1). MMP-9 and TIMP-1 mRNA levels were assessed using real-time PCR. Results: NRG-1β reduced the damage of SCII in the rats. The expression of MMP-9 protein and mRNA in NRG-1β treatment group was significantly lower than the model group (P

Sm3+, Eu3+ and Pr3+ doped Ca2LaTaO6 phosphors were fabricated by solid state phase sintering. XRD measurements were carried out to determine the crystal phases of the prepared phosphors. Excitation and emission spectra, decay curves were used to characterize their luminescent properties. The XRD results demonstrate that Sm3+, Eu3+ and Pr3+ doped Ca2LaTaO6 phosphors have the monoclinic phase. The excitation spectra demonstrate that they can be excited by ultraviolet, near ultraviolet and blue lights. The prominent emission bands of them mainly locate in red region. The calculated color purities of Ca2La0.6Eu0.4TaO6, Ca2La0.9Sm0.1TaO6 and Ca2La0.92Pr0.08TaO6 phosphors are 91.3%, 89.6% and 92.7%, respectively.

Development of latent functionally thermal fluid (LFTF) with excellent optical absorption and controllable heat transfer properties for direct absorption solar collector (DASC) is crucial in solar thermal utilization. In this study, the microcapsule, with melamine-formaldehyde (MF) resin shell and octadecane core, was prepared via in situ polymerization, as its shell was modified by reduced graphene oxide (rGO) and its core was doped with oleic acid coated Fe3O4 magnetic nanoparticles (OA-MNs). The microstructure, optical, thermal and magnetic properties of rGO modified magnetic phase change microcapsules (rGO-MPCMs) were investigated by means of various characterizations. The experimental results revealed that adding rGO substantially enhanced the thermal conductivity of magnetic phase change microcapsules (MPCMs) and only had tiny impact on the phase change behavior of MPCMs. Meanwhile, the thermal stability of octadecane in rGO-MPCMs was remarkably improved due to MF resin shell served as protective barrier. Furthermore, the rGO-MPCMs slurry exhibited better optical absorption and thermal storage capacities compared with MPCMs slurry and deionized water, thus enhancing photo-thermal conversion performance. Under an external magnetic field, the rGO-MPCMs in slurry presented excellent controllability and recyclability. Our research demonstrated that the rGO-MPCMs slurry, as a desirable working fluid, showed spacious application prospect for DASC.

Because of an aging population,osteoporotic vertebral fractures are becoming more frequent.Conservative therapy was considered the gold standard for treating osteoporotic vertebral compression fractures (OVCFs) in the past. Percutaneous vertebroplasty (PVP) or balloon kyphoplasty (BKP) as minimally invasive techniques are new treatments that are widely used for painful OVCFs. However, an increase in new vertebral compression fractures at non-treated levels following augmentation is of concern. There is no convincing evidence that new fractures are inevitable after augmentation compared to after conservative treatment, and it is still unclear whether further fractures are the consequence of augmentation or a result of the natural progression of osteoporosis.The objective of this study was to evaluate the new-level fracture risk after PVP or BKP compared with conservative (non-operative) treatment and to determine the dominant risk factor associated with new OVCFs.A meta-analysis of comparative studies was performed to evaluate the incidence of new vertebral fractures between vertebral augmentation, such as vertebroplasty and kyphoplasty, and no operation.The PubMed, ISI Web of Science, ELSEVIER ScienceDirect, and Cochrane Library databases and abstracts published in annual proceedings were systematically searched.In addition, we also retrieved data from references when titles met our inclusion criteria.Detailed searches of a number of online databases comparing operative and non-operative groups were performed. We included randomized controlled trials,clinical controlled trials,and prospective clinical studies to provide available data. All studies were reviewed by two reviewers independently, and all the references that met our inclusion criteria were searched for additional trials, using the guidelines set by the QUOROM (Quality of Reporting of Meta-analysis) statement.We evaluated 12 studies encompassing 1,328 patients in total, including 768 who underwent operation with polymethylmethacrylateand 560 who received non-operative treatments. For new-level vertebral fractures, our meta-analysis found no significant difference between the 2 methods, including total new fractures (P = 0.55) and adjacent fractures (P = 0.5). For pre-existing vertebral fractures, there was no significant difference between the 2 groups (operative and non-operative groups) (P = 0.24). Additionally,there was no significant difference in bone mineral density, both in the lumbar (P = 0 .13) and femoral neck regions (P = 0.37), between the 2 interventions.All studies we screened were published online except for unpublished articles. Moreover, only a few data sources could be extracted from the published studies.There were only 5 randomized clinical trials and 7 prospective studies that met our inclusion criteria.Vertebral augmentation techniques, such as vertebroplasty and kyphoplasty, have been widely used to treat osteoporotic vertebral fractures in order to alleviate back pain and correct the deformity, and it has been frequently reported that many new vertebral fractures occurred after this operation. Our analysis did not reveal evidence of an increased risk of fracture of vertebral bodies, especially those adjacent to the treated vertebrae, following augmentation with either method compared with conservative treatment.Key words: Vertebroplasty, kyphoplasty, new osteoporotic compression vertebral fracture, meta-analysis.