Mesenchymal derived exosomes enhance recovery of motor function in a monkey model of cortical injury.

BACKGROUND: Exosomes from mesenchymal stromal cells (MSCs) are endosome-derived vesicles that have been shown to enhance functional recovery in rodent models of stroke. OBJECTIVE: Building on these findings, we tested exosomes as a treatment in monkeys with cortical injury. METHODS: After being trained on a task of fine motor function of the hand, monkeys received a cortical injury to the hand representation in primary motor cortex. Twenty-four hours later and again 14 days after injury, monkeys received exosomes or vehicle control. Recovery of motor function was followed for 12 weeks. RESULTS: Compared to monkeys that received vehicle, exosome treated monkeys returned to pre-operative grasp patterns and latency to retrieve a food reward in the first three-five weeks of recovery. CONCLUSIONS: These results provide evidence that in monkeys exosomes delivered after cortical injury enhance recovery of motor function.

Spinal leptomeningeal neoplastic disease. Evaluation by MR, myelography and CT myelography.

Out of 16 patients, spinal leptomeningeal neoplastic disease was diagnosed by MRI in 4 patients, myelography in 14 patients and CT myelography in 12 cases. MR was superior to myelography in 2 patients, in another 2 patients MRI was equally diagnostic. The cerebrospinal fluid of every patient contained malignant cells. Histological evidence for primary central nervous system tumors was found in 5 cases. In 10 cases, non-neuraxial malignancy consisted of small cell carcinoma of the lung (7 cases), and leukemia and lymphoma (3 patients). In 1 patient, primary leptomeningeal malignant melanoma was confirmed at autopsy. Preferential thoracolumbar neoplastic morphologic manifestation correlated with the presence of conus and cauda equina syndrome in 9 patients, low back pain, paresthesia and spinal root signs in 7 patients. False-negative interpretation of myelography in 2 patients with positive MR findings, and the impressive sensitivity of gadolinium Dota to improve visualization of subarachnoid spread, favor MRI as an alternative imaging technique in the assessment of patients with suspected intradural extramedullary malignancy.