Minimally invasive spine stabilisation with long implants

Originally aimed at treating degenerative syndromes of the lumbar spine, percutaneous minimally invasive posterior fixation is nowadays even more frequently used to treat some thoracolumbar fractures. According to the modern principles of saving segment of motion, a short implant (one level above and one level below the injured vertebra) is generally used to stabilise the injured spine. Although the authors generally use a short percutaneous fixation in treating thoracolumbar fractures with good results, they observed some cases in which the high fragmentation of the vertebral body and the presence of other associated diseases (co-morbidities) did not recommend the use of a short construct. The authors identified nine cases, in which a long implant (two levels above and two levels below the injured vertebra) was performed by a percutaneous minimally invasive approach. Seven patients (five males/two females) were affected by thoracolumbar fractures. T12 vertebra was involved in three cases, L1 in two cases, T10 and L2 in one case, respectively. Two fractures were classified as type A 3.1, two as A 3.2, two as A 3.3 and one as B 2.3, according to Magerl. In the present series, there were also two patients affected by a severe osteolysis of the spine (T9 and T12) due to tumoral localisation. All patients operated on with long instrumentation had a good outcome with prompt and uneventful clinical recovery. At the 1-year follow-up, all patients except one, who died 11 months after the operation, did not show any radiologic signs of mobilisation or failure of the implant. Based on the results of the present series, the long percutaneous fixation seems to represent an effective and safe system to treat particular cases of vertebral lesions. In conclusion, the authors believe that a long implant might be an alternative surgical method compared to more aggressive or demanding procedures, which in a few patients could represent an overtreatment

Fully memristive neural networks for pattern classification with unsupervised learning

This paper was accepted for publication in the journal Nature Electronics and the definitive published version is available at https://doi.org/10.1038/s41928-018-0023-2.Neuromorphic computers comprised of artificial neurons and synapses could provide a more efficient approach to implementing neural network algorithms than traditional hardware. Recently, artificial neurons based on memristors have been developed, but with limited bio-realistic dynamics and no direct interaction with the artificial synapses in an integrated network. Here we show that a diffusive memristor based on silver nanoparticles in a dielectric film can be used to create an artificial neuron with stochastic leaky integrate-and-fire dynamics and tunable integration time, which is determined by silver migration alone or its interaction with circuit capacitance. We integrate these neurons with nonvolatile memristive synapses to build fully memristive artificial neural networks. With these integrated networks, we experimentally demonstrate unsupervised synaptic weight updating and pattern classification

The genomic landscape of schwannoma

Schwannomas are common peripheral nerve sheath tumors that can cause debilitating morbidities. We performed an integrative analysis to determine genomic aberrations common to sporadic schwannomas. Exome sequence analysis with validation by targeted DNA sequencing of 125 samples uncovered, in addition to expected NF2 disruption, recurrent mutations in ARID1A, ARID1B and DDR1. RNA sequencing identified a recurrent in-frame SH3PXD2A-HTRA1 fusion in 12/125 (10%) cases, and genomic analysis demonstrated the mechanism as resulting from a balanced 19-Mb chromosomal inversion on chromosome 10q. The fusion was associated with male gender predominance, occurring in one out of every six men with schwannoma. Methylation profiling identified distinct molecular subgroups of schwannomas that were associated with anatomical location. Expression of the SH3PXD2A-HTRA1 fusion resulted in elevated phosphorylated ERK, increased proliferation, increased invasion and in vivo tumorigenesis. Targeting of the MEK-ERK pathway was effective in fusion-positive Schwann cells, suggesting a possible therapeutic approach for this subset of tumors