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Veins are easy to obtain, have low immunogenicity, and induce a relatively weak inflammatory response. Therefore, veins have the potential to be used as conduits for nerve regeneration. However, because of the presence of venous valves and the great elasticity of the venous wall, the vein is not conducive to nerve regeneration. In this study, a novel tissue engineered nerve graft was constructed by combining normal dissected nerve microtissue with an autologous vein graft for repairing 10-mm peripheral nerve defects in rats. Compared with rats given the vein graft alone, rats given the tissue engineered nerve graft had an improved sciatic static index, and a higher amplitude and shorter latency of compound muscle action potentials. Furthermore, rats implanted with the microtissue graft had a higher density and thickness of myelinated nerve fibers and reduced gastrocnemius muscle atrophy compared with rats implanted with the vein alone. However, the tissue engineered nerve graft had a lower ability to repair the defect than autogenous nerve transplantation. In summary, although the tissue engineered nerve graft constructed with autologous vein and nerve microtissue is not as effective as autologous nerve transplantation for repairing long-segment sciatic nerve defects, it may nonetheless have therapeutic potential for the clinical repair of long sciatic nerve defects. This study was approved by the Experimental Animal Ethics Committee of Chinese PLA General Hospital (approval No. 2016-x9-07) on September 7, 2016.

Sensory and motor nerve fibers of peripheral nerves have different anatomies and regeneration functions after injury. To gain a clear understanding of the biological processes behind these differences, we used a labeling technique termed isobaric tags for relative and absolute quantitation to investigate the protein profiles of spinal nerve tissues from Sprague-Dawley rats. In response to Wallerian degeneration, a total of 626 proteins were screened in sensory nerves, of which 368 were upregulated and 258 were downregulated. In addition, 637 proteins were screened in motor nerves, of which 372 were upregulated and 265 were downregulated. All identified proteins were analyzed using the Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis of bioinformatics, and the presence of several key proteins closely related to Wallerian degeneration were tested and verified using quantitative real-time polymerase chain reaction analyses. The differentially expressed proteins only identified in the sensory nerves were mainly relevant to various biological processes that included cell-cell adhesion, carbohydrate metabolic processes and cell adhesion, whereas differentially expressed proteins only identified in the motor nerves were mainly relevant to biological processes associated with the glycolytic process, cell redox homeostasis, and protein folding. In the aspect of the cellular component, the differentially expressed proteins in the sensory and motor nerves were commonly related to extracellular exosomes, the myelin sheath, and focal adhesion. According to the Kyoto Encyclopedia of Genes and Genomes, the differentially expressed proteins identified are primarily related to various types of metabolic pathways. In conclusion, the present study screened differentially expressed proteins to reveal more about the differences and similarities between sensory and motor nerves during Wallerian degeneration. The present findings could provide a reference point for a future investigation into the differences between sensory and motor nerves in Wallerian degeneration and the characteristics of peripheral nerve regeneration. The study was approved by the Ethics Committee of the Chinese PLA General Hospital, China (approval No. 2016-x9-07) in September 2016.

Background Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease that is regionally distributed in Asia, with high fatality. Constructing the transmission model of SFTS could help provide clues for disease control and fill the gap in research on SFTS models. Methods We built an SFTS transmission dynamics model based on the susceptible–exposed–infectious–asymptomatic–recovered (SEIAR) model and the epidemiological characteristics of SFTS in Jiangsu Province. This model was used to evaluate the effect by cutting off different transmission routes and taking different interventions into account, to offer clues for disease prevention and control. Results The transmission model fits the reported data well with a minimum R2 value of 0.29 and a maximum value of 0.80, P Conclusions The model we have built can be used to simulate the transmission of SFTS to help inform disease control. It is noteworthy that cutting off the environment-to-humans transmission route in the model had the greatest effect on SFTS prevention and control. Graphical Abstract

Between nerve defects, a bridge formed by multiple cells is the fundamental structure for guiding axons across this damaged region. Here, we developed a functional material that mimics hypoxia during the early stages of nerve regeneration by deferoxamine. We used this material and single-cell sequencing to analyze the "bridge" structure between peripheral nerve defects. We found that hypoxia in damaged tissues might play a key role in stimulating macrophages, promoting endothelial-to-mesenchymal transition, and driving the migration of endothelial cells to the injured region to form regenerative bridge tissue and guide the subsequent regeneration of Schwann cells and axons. The results showed that the final nerve defect repair outcomes were similar with autografts after intervention by this material. This study challenges the view that hypoxia is exclusively involved in peripheral nerve regeneration and provides a potentially valuable candidate material for clinical use.

Background: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease that is regionally distributed in Asia with high fatality. Constructing the transmissibility model of SFTS could help provide clues for the intervention of disease control and fill the gap in the research of the SFTS model.Methods: Based on the Susceptible–Exposed–Infectious–Symptomatic–Recovered (SEIAR) model and combined with the epidemiological characteristics of SFTS in Jiangsu Province. An SFTS transmission dynamics model was built to evaluate the effect through cutting off the different transmission routes and taking different interventions, to offer clues for disease prevention and control, and filled the gap in research of the SFTS model. Results: For the transmission model of SFTS, the fitting effect of case data and model is great. Meanwhile, cutting off the transmission routes of the environment have the greatest effect on the prevention and control of SFTS, but isolation and shorten the course of the disease did not gain more effect.Conclusions: This study is determined that cutting off the transmission routes from the environment to humans had the greatest effect on SFTS prevention and control.

In our previous study, we investigated the dynamic expression of cytokines in the distal nerve stumps after peripheral nerve injury using microarray analysis, which can characterize the dynamic expression of proteins. In the present study, we used a rat model of right sciatic nerve transection to examine changes in the expression of cytokines at 1, 7, 14 and 28 days after injury using protein microarray analysis. Interleukins were increased in the distal nerve stumps at 1-14 days post nerve transection. However, growth factors and growth factor-related proteins were mainly upregulated in the proximal nerve stumps. The P-values of the inflammatory response, apoptotic response and cell-cell adhesion in the distal stumps were higher than those in the proximal nerve stumps, but the opposite was observed for angiogenesis. The number of cytokines related to axons in the distal stumps was greater than that in the proximal stumps, while the percentage of cytokines related to axons in the distal stumps was lower than that in the proximal nerve stumps. Visualization of the results revealed the specific expression patterns and differences in cytokines in and between the proximal and distal nerve stumps. Our findings offer potential therapeutic targets and should help advance the development of clinical treatments for peripheral nerve injury. Approval for animal use in this study was obtained from the Animal Ethics Committee of the Chinese PLA General Hospital on September 7, 2016 (approval No. 2016-x9-07).

The failure prediction and life assessment method based on physics of failure (PoF) approach has been more widely used. This paper mainly describes the fatigue life assessment process design of board-level PCBA based on PoF approach. At first, the complete board-level PCBA fatigue life evaluation process is given, and the application of PoF model in various stages of the evaluation process is stated. Then a detailed description of their applicable conditions, as well as input and output parameters when they are applicated are given, thus providing a reference for the fatigue life evaluation and reliability design and evaluation of PCBA.

The L-type Ca2+ channel (LTCC) Cav1.3 plays a critical role in generating electrical activity in atrial myocytes and cardiac pacemaker cells. However, the molecular and functional basis of Cav1.3 modulation in atrial myocytes has not yet been fully understood. By using the yeast two-hybrid system (Y2H), a Cav1.3-associated protein was screened, which was identified as Snapin. Physical interaction and co-localization between Snapin and Cav1.3 were then confirmed in both the heterologous expression system and mouse atrial myocytes. Direct interaction between them was additionally addressed in a GST pull down assay. Furthermore, both total and membrane expressions of Cav1.3 were significantly impaired by Snapin overexpression, resulting in the ubiquitin-proteasomal degradation of Cav1.3 and a consequent reduction of the densities of whole-cell ICa-L. Snapin-induced down-regulation of Cav1.3 was reversed by SNAP-23 competitively. What is more important is that the depressed-expression of Cav1.3 paralleled with enhanced-expression of Snapin was documented in atrial samples from atrial fibrillation (AF) patients. Our results provide the evidence of a direct regulatory role of Snapin on Cav1.3 channels in atrial myocytes, and highlight a potential role of Snapin in the regulation of Cav1.3 in atrial arrhythmogenesis.

Flexible nerve guide conduits (NGCs) are desired in peripheral nerve reconstruction near the joints. Inspired by the engineered structure of the helical tube, we addressed the problems of conventional NGCs often mentioned in clinical feedback. We developed a type of helix-flexible NGC (HF-NGC) and evaluated its mechanical properties as well as its flexibility, and it performed excellently during in vitro tests. During the in vivo tests, HF-NGCs and conventional nonflexible NGCs (NF-NGCs) were implanted in a rat sciatic nerve defect model. A short-term investigation showed that Schwan cells (SCs) infiltrated into the helical groove, and most of them belonged to the activated SC type. Compared with NF-NGCs, HF-NGCs had fewer apoptotic SCs. In the long term investigation, HF-NGCs maintained flexibility in vivo after 3 months. Analyses of the morphometric parameters of nerve fibers and the static sciatic index showed that the HF-NGCs had similar regeneration outcomes to those of traditional NF-NGCs. Therefore, this style of HF-NGC could be used to repair peripheral nerve damage in a cross-joint region with less tension during operation and easy to postoperative rehabilitation. We believe that the HF-NGC is a potentially valuable candidate for clinical use.

In older adults, the prevalence of osteoarthritis (OA) increases directly with age and is the most common cause of chronic disability. It is necessary to recognize that OA is a degenerative disease that strongly correlates with age, and often promotes elevated levels of cartilage injury. Chondrocytes undergo an age-dependent decline in proliferative and synthetic capacity. It is thought that cellular senescence may play a significant role in the pathology of OA, with chondrocytes exhibiting a variety of senescence-associated phenotypes. In this review, we discuss cellular senescence and its relationship with OA. More importantly, we introduce novel strategies for the modulation of cellular senescence, including the use of sirtuin 6, mammalian target of rapamycin, N-acetyl-l-cysteine, proteoglycan-4 and senolytic, which may help to delay senescence and improve cartilage regeneration in the aging population.

A pathological hallmark of Alzheimer disease (AD) is the accumulation of misfolded hyperphosphorylated microtubule-associated protein Tau within neurons, forming neurofibrillary tangles and leading to synaptic dysfunction and neuronal death. Here we study sequence-dependent abnormal aggregation of human fragment Tau244–372 in an inducible cell model. As evidenced by confocal laser scanning microscopy, Western blot, and immunogold electron microscopy, fibril-forming motifs are essential and sufficient for abnormal aggregation of Tau244–372 in SH-SY5Y neuroblastoma cells induced by Congo red: when its two fibril-forming segments PHF6 and PHF6* are deleted, Tau244–372 does lose its ability to form fibrils in SH-SY5Y cells, and the replacement of PHF6 and PHF6* with an unrelated amyloidogenic sequence IFQINS from human lysozyme does rescue the fibril-forming ability of Tau244–372 in SH-SY5Y cells. By contrast, insertion of a non-fibril forming peptide GGGGGG does not drive the disabled Tau244–372 to misfold in SH-SY5Y cells. Furthermore, as revealed by quantum dots based probes combined with annexin V staining, annexin V-FITC apoptosis detection assay, and immunofluorescence, fibril-forming motifs are essential and sufficient for early apoptosis of living SH-SY5Y cells induced by abnormal aggregation of Tau244–372. Our results suggest that fibril-forming motifs could be the determinants of Tau protein tending to misfold in living cells, thereby inducing neuronal apoptosis and causing the initiation and development of AD.

The global economic and social developments depend largely on fossil fuels nowadays. To cope with energy crisis and environment problems caused by consumption of fossil fuels, the renewable energy exploitation is an alternative path. As one kind of renewable ocean energy which can be applied into production, tidal energy is mainly utilized in electricity generation. China has abundant tidal energy resource, which mainly distribute in the southeast coastal areas where power supply is insufficient. China's tidal power generation started in 1958, and some experience and technologies have been accumulated from the long-time history of tidal power station construction and operation. At present, China’s tidal energy’s development and utilization are still in low level, and remain plagued by several challenges, such as high cost, and insufficiency of preferential policies and regulations. While, China's tidal power generation must be very promising in the foreseeable future, with a great deal of attention paid to the utilization of renewable energy and the perception of sustainable development.

Positive semi-definiteness is a critical property in Support Vector Machine (SVM) methods to ensure efficient solutions through convex quadratic programming. In this paper, we introduce a projection matrix on indefinite kernels to formulate a positive semi-definite one. The proposed model can be regarded as a generalized version of the spectrum method (denoising method and flipping method) by varying parameter λ. In particular, our suggested optimal λ under the Bregman matrix divergence theory can be obtained using unconstrained optimization. Experimental results on 4 real world data sets ranging from glycan classification to cancer prediction show that the proposed model can achieve better or competitive performance when compared to the related indefinite kernel methods. This may suggest a new way in motif extractions or cancer predictions.

Nerve conduits enhance nerve regeneration in the repair of long-distance peripheral nerve defects. To help optimize the effectiveness of nerve conduits for nerve repair, we developed a multi-step electrospinning process for constructing nerve guide conduits with aligned nanofibers. The alignment of the nerve guide conduits was characterized by scanning electron microscopy and fast Fourier transform. The mechanical performance of the nerve guide conduits was assessed by testing for tensile strength and compression resistance. The biological performance of the aligned fibers was examined using Schwann cells, PC12 cells and dorsal root ganglia in vitro. Immunohistochemistry was performed for the Schwann cell marker S100 and for the neurofilament protein NF200 in PC12 cells and dorsal root ganglia. In the in vivo experiment, a 1.5-cm defect model of the right sciatic nerve in adult female Sprague-Dawley rats was produced and bridged with an aligned nerve guide conduit. Hematoxylin-eosin staining and immunohistochemistry were used to observe the expression of ATF3 and cleaved caspase-3 in the regenerating matrix. The recovery of motor function was evaluated using the static sciatic nerve index. The number of myelinated fibers, axon diameter, fiber diameter, and myelin thickness in the distal nerve were observed by electron microscopy. Gastrocnemius muscle mass ratio was also determined. The analyses revealed that aligned nanofiber nerve guide conduits have good mechanical properties and can induce Schwann cells, PC12 cells and dorsal root ganglia to aggregate along the length of the nanofibers, and promote the growth of longer axons in the latter two (neuronal) cell types. The aligned fiber nerve conduits increased the expression of ATF3 and cleaved caspase-3 at the middle of the regenerative matrix and at the distal nerve segment, improved sciatic nerve function, increased muscle mass of the gastrocnemius muscle, and enhanced recovery of distal nerve ultrastructure. Collectively, the results show that highly aligned nanofibers improve the performance of the nerve conduit bridge, and enhance its effectiveness in repairing peripheral nerve defects.

Ischemic complications associated with microsurgical clipping and endovascular coiling affects the outcome of patients with intracranial aneurysms. We prospectively evaluated 58 intracranial aneurysm patients who had neurological deterioration or presented with poor grade (Hunt-Hess grades III and IV), aneurysm size >13 mm and multiple aneurysms after clipping or coiling. Thirty patients had ischemic complications (52%) as demonstrated by whole-brain CT perfusion (WB-CTP) combined with CT angiography (CTA). Half of these 30 patients had treatment-associated reduction in the diameter of the parent vessels (n=6), ligation of the parent vessels or perforating arteries (n=2), and unexplained or indistinguishable vascular injury (n=7); seven of these 15 (73%) patients suffered infarction. The remaining 15 patients had disease-associated cerebral ischemia caused by generalized vasospasm (n=6) and focal vessel vasospasm (n=9); six of these 15 (40%) patients developed infarction. Three hemodynamic patterns of ischemic complications were found on WB-CTP, of which increased time to peak, time to delay and mean transit time associated with decreased cerebral blood flow and cerebral blood volume were the main predictors of irreversible ischemic lesions. In conclusion, WB-CTP combined with CTA can accurately determine the cause of neurological deterioration and classify ischemic complications. This combined approach may be helpful in assessing hemodynamic patterns and monitoring operative outcomes.

Implementing failure mode criticality analysis on metro door system could help to find the failure modes which have great criticality on door system, and it can be helpful for perfecting door maintenance decision. A criticality analysis method which is based on fuzzy evidential reasoning and grey theory is proposed. First, fuzzy belief structure is employed to assess failure modes; second, grey theory is used to calculate the degrees of grey relation of failure modes, that the experiment results show that three failure modes, including “EDCU function is broken,” “Limit switch S1 wears out,” and “Nut component wears out,” have great damage on door system. The results can be used for optimal design and maintenance of the metro door system.

An algorithm is presented for detecting foreground objects with multi-scale wavelet transformation and color ratio difference. Multi-scale wavelet transformation method is used to segment moving objects based on spatial property. Ratio differences between two adjacent pixels in four different directions are used to classify object pixels. RGB color space is selected to segment moving foregrounds and eliminate cast shadows instead of complex color models. The developed approach does not require any complex supervised training phase, manual calibration or hypothesis in removing shadow. Experiments have highlighted that the proposal is efficient to segment foregrounds and suppress shadows.