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Novik, L.

Publications and source records attributed to Novik, L..

2 recordsLinked to original sources

An Automated Behavioral Apparatus to Assess Distal Forelimb Function in Non-Human Primates

BackgroundPrimate distal forelimb behaviors are commonly assessed using reach-to-grasp tasks. While these tasks are widely recognized as sensitive assays for forelimb function, they often require experimenter input, lack precise temporal cues for physiological monitoring, and can be expensive.\n\nNew MethodUsing components developed by open-source electronics platforms, we have designed and tested a low-cost system to measure distal forelimb function in non-human primates. Our system is inexpensive; it is made primarily of acrylic and 3D printed plastic parts. Our control software, developed in MATLAB, was also used to control two cameras in order to capture and process video during behavior. The system was equipped with sensors, motors and microcontrollers to control the timing of the task and facilitate synchronization between behavior and neurophysiology with high temporal precision.\n\nResultsWe demonstrate that this system can be used to monitor motor recovery after stroke and investigate neurophysiological correlates of motor control.\n\nComparison with Existing MethodsCompared to a previous version of this task, our setup reduces experimenter input while providing unbiased delivery of behavioral cues and behavioral measurements with the temporal precision necessary for electrophysiological studies.\n\nConclusionsIn summary, our system will allow unbiased monitoring of forelimb function in both healthy and injured animals that is compatible with electrophysiological studies.

neuroscience

Quantitative analysis of synaptic pathology and neuroinflammation: an initial study in a female rhesus monkey model of the “synaptic” phase of Alzheimer’s disease

BackgroundSoluble oligomers of the A{beta} peptide (A{beta}Os) are toxins that target and disrupt synapses. Generation of A{beta}Os has been recently recognized as a probable initiating event in Alzheimers disease (AD), leading to cognitive impairment. There is a translational gap in AD studies, with promising drugs developed based on work in rodent models failing in AD patients in clinical trials. Additionally, although women have a two-fold greater lifetime risk of developing AD compared to men, females have not been a focus of preclinical studies. Thus, we sought to develop a model of A{beta}O toxicity in female rhesus monkeys, to take advantage of the more highly differentiated cortical structure in this species as well as the similarities in the endocrine system between rhesus monkeys and humans.\n\nMethodsRepeated intracerebroventricular (i.c.v) injections of A{beta}Os were performed in adult female rhesus monkeys. Controls were unoperated aged matched monkeys. High-resolution confocal microscopy and morphometric analysis of Alexa 568 (A568) filled neurons were used to evaluate synaptic, neuronal, and glial markers in the dorsolateral prefrontal cortex (dlPFC) and hippocampus after A{beta}O injections. Cerebrospinal fluid (CSF) and brain tissue were also collected and analyzed for biomarkers of AD pathology, including: phosphorylated Tau protein (pTau), total Tau, A{beta}1-42, A{beta}1-40 and TNF- levels.\n\nResultsHere, we report that A{beta}O injection into the lateral ventricle of the brain induces loss of 37% of thin spines in targeted dlPFC neurons, an area highly vulnerable in AD and aging. Further, A{beta}Os associate with the synaptic marker PSD95, inducing loss of more than 60% of local excitatory synapses. A{beta}Os induce a robust neuroinflammatory response in the hippocampus, far from the injection site, with numerous activated ameboid microglia and TNF- release. Finally, A{beta}Os increased CSF levels of A{beta}1-42, pTau Ser396 and pTau Ser199, but not A{beta}1-40 or total Tau.\n\nConclusionsThese initial findings from detailed quantitative analysis of effects of A{beta}O administration on synapses in a female nonhuman primate model are a very promising step toward understanding the mechanism of early AD pathogenesis in the primate brain, and may help develop an effective disease-modifying therapy of high relevance to womens health.

neuroscience