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The 2014 Ebola outbreak in West Africa required the rapid testing of clinical material for the presence of potentially high titre Ebola virus (EBOV). Safe, fast and effective methods for the inactivation of such clinical samples are required so that rapid diagnostic tests including downstream analysis by RT-qPCR or nucleotide sequencing can be carried out. One of the most commonly used guanidinium - based denaturing agents, AVL (Qiagen) has been shown to fully inactivate EBOV once ethanol is added, however this is not compatible with the use of automated nucleic acid extraction systems. Additional inactivation agents need to be identified that can be used in automated systems. A candidate inactivation agent is Triton X-100, a non-denaturing detergent that is frequently used in clinical nucleic acid extraction procedures and has previously been used for inactivation of EBOV. In this study the effect of 0.1% and 1.0% Triton X-100 (final concentration 0.08% and 0.8% respectively) alone and in combination with AVL on the viability of EBOV (10 6 TCID 50 /ml) spiked into commercially available pooled negative human serum was tested. The presence of viable EBOV in the treated samples was assessed by carrying out three serial passages of the samples in Vero E6 cells (37°C, 5% CO 2 , 1 week for each passage). At the end of each passage the cells were observed for evidence of cytopathic effect and samples were taken for rRT-PCR analysis for the presence of EBOV RNA. Before cell culture cytotoxic components of AVL and Triton X-100 were removed from the samples using size exclusion spin column technology or a hydrophobic adsorbent resin. The results of this study showed that EBOV spiked into human serum was not fully inactivated when treated with either 0.1% (v/v) Triton X-100 for 10 mins or 1.0% (v/v) Triton X-100 for 20 mins (final concentrations 0.08% and 0.8% Triton X-100 respectively). AVL alone also did not consistently provide complete inactivation. Samples treated with both AVL and 0.1% Triton X-100 for 10 or 20 mins were shown to be completely inactivated. This treatment is compatible with downstream analysis by RT-qPCR and next generation sequencing., (Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.)

Cats performed flexion movements of the forearm, and the discharge of interpositus and red nucleus neurons was examined for relationships to the motion and to the EMG activity of agonist and antagonist muscles. It is shown that, over a wide range in the time course of the motion, the activity of the neurons is covariant with both the EMG and the movement parameters, in particular, the velocity. Also, the discharge of the interpositus neurons is modulated in phase with the velocity of passive movement. It is concluded that during fast, intentional movements, sensory input data generated by motion is a major determinant of the output of the interpositus nucleus. Furthermore, the results are consistent with the concept that this output provides a continuous modulation of spinal segmental mechanisms by way of the red nucleus and rubrospinal tract.

The relationship between unit activity in interpositus (8 units) and red nuclei (11 units) and the EMG activity of the biceps during intentional elbow flexion movements was investigated by means of cross-correlation analysis. This analysis showed that there were long-lasting (200 msec) changes in the probability of EMG activity both before and after a single spike in neurons which covaried with the motor output. The dependence of the activity of these units on sensory inputs was investigated by (1) calculating the quantitative relationship between angular displacement and unit activity and (2) recording unit activity after the sensory input from peripheral afferents had been eliminated by dorsal rhizotomy.