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Abstract Axonal growth cones mediate axonal guidance and growth regulation. We show that migrating neurons in mice possess a growth cone at the tip of their leading process, similar to that of axons, in terms of the cytoskeletal dynamics and functional responsivity through protein tyrosine phosphatase receptor type sigma (PTPσ). Migrating-neuron growth cones respond to chondroitin sulfate (CS) through PTPσ and collapse, which leads to inhibition of neuronal migration. In the presence of CS, the growth cones can revert to their extended morphology when their leading filopodia interact with heparan sulfate (HS), thus re-enabling neuronal migration. Implantation of an HS-containing biomaterial in the CS-rich injured cortex promotes the extension of the growth cone and improve the migration and regeneration of neurons, thereby enabling functional recovery. Thus, the growth cone of migrating neurons is responsive to extracellular environments and acts as a primary regulator of neuronal migration.

In the temperature programmed desorption-mass spectrometry (TPD-MS) experiments, the time lag and broadening of the gas evolved from the sample until it is detected by the MS detector can be a problem. The deconvolution method was successfully applied to TPD-MS. The pulse injection of N2, 1-butene, CO2, and H2O gasses in the TPD-MS system showed the same MS intensity-time response. This result suggests the MS signal can be used as an impulse response function of deconvolution analysis. The present TPD-MS method was applied to evaluate the dehydration from zeolites during heating. The shape of differential thermogravimetry (DTG) curves was in good agreement with deconvolved TPD-MS curves. The signal-to-noise ratio of TPD-MS is higher than that of DTG. The present method can be applicable for TG-MS or Fast scanning calorimetry (FSC)-MS in the upcoming study.