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Neuron-on-chip (NoC) systems-microfluidic devices in which neurons are cultured-have become a promising alternative to replace or minimize the use of animal models and have greatly facilitated in vitro research. Here, we review and discuss current developments in neuron-on-chip platforms, with a particular emphasis on existing biological models, culturing techniques, biomaterials, and topologies. We also discuss how the architecture, flow, and gradients affect neuronal growth, differentiation, and development. Finally, we discuss some of the most recent applications of NoCs in fundamental research (i.e., studies on the effects of electrical, mechanical/topological, or chemical stimuli) and in disease modeling.
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The U.S. needs early warning systems to help it contain the spread of infectious diseases. Conventional early warning systems use lab-test results or dynamic records to signal early warning signs. New early warning systems can supplement these data with indicators of public awareness like news articles and search queries. This study aims to explore the potential of utilizing social media data to enhance early warning of the COVID-19 outbreak. To demonstrate the feasibility, this study conducts a retrospective analysis and investigates more than 14 million related Twitter postings in the date range from January 20 to March 10, 2020. With the aid of natural language processing tools and machine learning classifiers, this study classifies each of these tweets into either a signal or a non-signal. In this study, a "signal" tweet implies that the user recognized the COVID-19 outbreak risk in the U.S. This study then proposes a parameter "signal ratio" to signal warning signs of the COVID-19 pandemic over periods. Results reveal that social media data and the signal ratio can detect the hazards ahead of the COVID-19 outbreak. This claim has been validated with a leading time of 16 days through the comparison to other referenced methods based on Google trends or media news.
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<p><b>INTRODUCTION</b>This study aimed to evaluate the clinical and radiological outcomes, and safety and efficacy of percutaneous pedicle screw fixation (PPSF) in the treatment of thoracolumbar burst fractures.</p><p><b>METHODS</b>This was a retrospective review of patients with thoracolumbar burst fractures treated with PPSF in a single hospital from 2010 to 2011. Baseline data included patient demographics, mechanism of injuries, fracture level, neurologic status and the number of percutaneous screws inserted. Kyphotic angle correction, vertebral body height restoration and mid-sagittal canal diameter improvement were used to assess radiological outcome. Screw misplacement, operative complications, functional improvement (ASIA score) and pain score on visual analogue scale were used to assess safety and clinical outcomes.</p><p><b>RESULTS</b>21 patients with 25 thoracolumbar burst fractures were treated with 134 percutaneous screws. There was significant improvement in kyphotic angle correction (mean difference 6.1 degrees, p = 0.006), restoration of anterior and posterior vertebral height (mean difference 19.7%, p < 0.01 and mean difference 6.6%, p = 0.007, respectively) and mid-sagittal canal diameter (mean difference 15.6%, p = 0.007) on discharge. These improvements remained statistically significant at six months post operation for restoration of anterior vertebral body height (mean difference 9.8%, p = 0.05) and mid-sagittal diameter (mean difference 30.0%, p < 0.01).</p><p><b>CONCLUSION</b>In this first local review, we have shown that PPSF is a relatively safe and effective technique for treating selected thoracolumbar burst fractures, and that it yields satisfactory results. However, its long-term outcome and efficacy need to be further evaluated.</p>