Effect of Neuromodulation of Short-Term Plasticity on Information Processing in Hippocampal Interneuron Synapses

Neurons convey information about the complex dynamic environment in the form of signals. Computational neuroscience provides a theoretical foundation toward enhancing our understanding of nervous system. The aim of this dissertation is to present techniques to study the brain and how it processes information in particular neurons in hippocampus. We begin with a brief review of the history of neuroscience and biological background of basic neurons. To appreciate the importance of information theory, familiarity with the information theoretic basics is required, these basics are presented in Chapter 2. In Chapter 3, we use information theory to estimate the amount of information postsynaptic responses carry about the preceding temporal activity of hippocampal interneuron synapses and estimate the amount of synaptic memory. In Chapter 4, we infer parsimonious approximation of the data through analytical expression for calcium concentration and postsynaptic response distribution when calcium decay time is significantly smaller that the interspike intervals. In Chapter 5, we focus on the study and use of Causal State Splitting Reconstruction (CSSR) algorithm to capture the structure of the postsynaptic responses. The CSSR algorithm captures patterns in the data by building a machine in the form of visible Markov Models. One of the main advantages of CSSR with respect to Markov Models is that it builds states containing more than one histories, so the obtained machines are smaller than the equivalent Markov Model

Engineering Long Range Distance Independent Entanglement through Kondo Impurities in Spin Chains

We investigate the entanglement properties of the Kondo spin chain when it is prepared in its ground state as well as its dynamics following a single bond quench. We show that a true measure of entanglement such as negativity enables to characterize the unique features of the gapless Kondo regime. We determine the spatial extent of the Kondo screening cloud and propose an ansatz for the ground state in the Kondo regime accessible to this spin chain; we also demonstrate that the impurity spin is indeed maximally entangled with the Kondo cloud. We exploit these features of the entanglement in the gapless Kondo regime to show that a single local quench at one end of a Kondo spin chain may always induce a fast and long lived oscillatory dynamics, which establishes a high quality entanglement between the individual spins at the opposite ends of the chain. This entanglement is a footprint of the presence of the Kondo cloud and may be engineered so as to attain - even for very large chains- a constant high value independent of the length; in addition, it is thermally robust. To better evidence the remarkable peculiarities of the Kondo regime, we carry a parallel analysis of the entanglement properties of the Kondo spin chain model in the gapped dimerised regime where these remarkable features are absent

Fatty Infiltration in Multifidus Muscles and its Association With Spinal MRI Findings

Background: The present cross sectional study was conducted to evaluate the relation between fatty infiltration (FI) in multifidus muscles and spinal MRI findings among patients who referred to Sina Athar and Kosar imaging centers of Shahid Beheshti University of Medical SciencesMethods: Discovertebral and facet joint degenerative changes, intervertebral foraminal narrowing, disk herniation and central canal stenosis in all lumbar levels and FI in multifidus muscles at the level of L5 vertebra were assessed on magnetic resonance imaging (MRI) studies of 333 patients, and correlation of these MRI changes with FI was identified.Results: Among 333 patients (174 female), whose data were analyzed, 316 patients mentioned a positive history of back pain. We observed a significant relation between female sex and higher age with degrees of multifidus FI in L5 level. No significant association was found between the existence of back pain and the rate of multifidus FI. There was a significant negative relation between the activity level and the amount of multifidus FI. Considering weekly exercise level and hours of computer use, this association was not observed. Evaluating the relation between end plate and facet joint degenerative process and also neuroforaminal stenosis with multifidus FI, a statistically significant relation was noted. This correlation was not observed for central canal stenosis.Conclusion: We concluded that the degree of multifidus FI was remarkably higher in female gender, older ages and subjects with more sedentary lifestyle. Moreover, a significant correlation existed between abnormal MRI imaging findings (degenerative process, discopathies, foraminal stenosis) and multifidus FI

Human Gait Database for Normal Walk Collected by Smart Phone Accelerometer

The goal of this study is to introduce a comprehensive gait database of 93 human subjects who walked between two endpoints during two different sessions and record their gait data using two smartphones, one was attached to the right thigh and another one on the left side of the waist. This data is collected with the intention to be utilized by a deep learning-based method which requires enough time points. The metadata including age, gender, smoking, daily exercise time, height, and weight of an individual is recorded. this data set is publicly available

A dietary intervention for chronic diabetic neuropathy pain: a randomized controlled pilot study

Background: Diabetic neuropathy is a common and often debilitating condition for which available treatments are limited. Because a low-fat plant-based diet has been shown to improve glycemic control in individuals with type 2 diabetes, we hypothesized that such a diet would reduce painful symptoms of diabetic neuropathy. Methods: In this 20-week pilot study, individuals with type 2 diabetes and painful diabetic neuropathy were randomly assigned to two groups. The intervention group was asked to follow a low-fat, plant-based diet, with weekly classes for support in following the prescribed diet, and to take a vitamin B12 supplement. The control group was asked to take the same vitamin B12 supplement, but received no other intervention. At baseline, midpoint and 20 weeks, clinical, laboratory and questionnaire data were collected. Questionnaires included an analog ‘worst pain’ scale, Michigan Neuropathy Screening Instrument, global impression scale, Short Form McGill Pain Questionnaire, Neuropathy Total Symptom Score, a weekly pain diary and Norfolk Quality of Life Questionnaire. Results: After 20 weeks, body weight change with the intervention was −6.4 kg (95% confidence interval (CI) −9.4 to −3.4, PP=0.03) with the intervention in an effect size analysis. The between-group difference in change in pain, as measured by the McGill pain questionnaire, was −8.2 points (95% CI −16.1 to −0.3, P=0.04). Michigan Neuropathy Screening Instrument questionnaire score change was −1.6 points (95% CI −3.0 to −0.2, P=0.03). Conclusions: Improvements were seen in some clinical and pain measures. This pilot study suggests the potential value of a plant-based diet intervention, including weekly support classes, for treating painful diabetic neuropathy

Functional Outcomes of Temporomandibular Joint Ankylosis Treatments: A 10-year cohort study

Introduction : Ankylosis of the temporomandibular joint (TMJ) is a disabling condition due to the fusion of joint to the base of skull and results in mouth opening limitation. Several surgical techniques have been described for treatment of this condition but no consensus has been reached. This study sought to assess the success of treatment with regard to long-term functional improvement and rate of complications in ankylosis patients during a 10-year period. Materials and Methods: Patients who underwent unilateral or bilateral condylectomy without joint reconstruction during 2001-2011 in the Maxillofacial Surgery Department of Shariati Hospital were evaluated in this historical cohort study. The patients were recalled to ensure the accuracy of information in their medical records and were clinically examined. Improvement in their joint function and rate of complications were evaluated. Data were analyzed using Wilcoxon Signed rank test, multivariate tests, Mauchly's sphericity test and McNemar’s test. Results: A total of 27 subjects (13 males and 14 females) with a mean age of 34.8 years and 6.1 years mean duration of follow-up were evaluated. The results of observation showed that trauma was the most common cause of ankylosis (63%). The most common type of ankyloses was fibrous (55.6%) and 55.6% of the patients had bilateral ankylosis. Maximum mouth opening (MMO), the amount of lateral movement and open bite significantly improved after the operation (P<0.001). Frontal, zygomatic and buccal nerves had been injured in 4, 4 and 3 patients, respectively during the operation. Conclusion: Condylectomy without reconstruction significantly improves the TMJ function in patients with TMJ ankylosis with regard to MMO, the amount of lateral movement, maintenance of occlusion and the skeletal form

Imaging findings associated with cognitive performance in primary lateral sclerosis and amyotrophic lateral sclerosis

Introduction: Executive dysfunction occurs in many patients with amyotrophic lateral sclerosis (ALS), but it has not been well studied in primary lateral sclerosis (PLS). The aims of this study were to (1) compare cognitive function in PLS to that in ALS patients, (2) explore the relationship between performance on specific cognitive tests and diffusion tensor imaging (DTI) metrics of white matter tracts and gray matter volumes, and (3) compare DTI metrics in patients with and without cognitive and behavioral changes. Methods: The Delis-Kaplan Executive Function System (D-KEFS), the Mattis Dementia Rating Scale (DRS-2), and other behavior and mood scales were administered to 25 ALS patients and 25 PLS patients. Seventeen of the PLS patients, 13 of the ALS patients, and 17 healthy controls underwent structural magnetic resonance imaging (MRI) and DTI. Atlas-based analysis using MRI Studio software was used to measure fractional anisotropy, and axial and radial diffusivity of selected white matter tracts. Voxel-based morphometry was used to assess gray matter volumes. The relationship between diffusion properties of selected association and commissural white matter and performance on executive function and memory tests was explored using a linear regression model. Results: More ALS than PLS patients had abnormal scores on the DRS-2. DRS-2 and D-KEFS scores were related to DTI metrics in several long association tracts and the callosum. Reduced gray matter volumes in motor and perirolandic areas were not associated with cognitive scores. Conclusion: The changes in diffusion metrics of white matter long association tracts suggest that the loss of integrity of the networks connecting fronto-temporal areas to parietal and occipital areas contributes to cognitive impairment

Frequency, Symptomology, and Course of HIV-Associated ALS: Case Series and Review

The pathogenesis of Amyotrophic Lateral Sclerosis (ALS) is not entirely understood, but there appears to be a relationship between ALS and viral infections including HIV-1. The impact of HIV infection and antiretroviral therapy on the presentation, diagnosis, and progression of ALS is not well-defined. This is a retrospective chart review in which we analyzed records of patients who presented to the ALS Clinic from September 2006 to June 2018. We sought to identify HIV-positive patients receiving antiretroviral therapy who were subsequently diagnosed with ALS. Our primary goals were to analyze prevalence of HIV positivity among our ALS patients, describe their ALS presentation and progression, and compare our study cases to ALS characteristics in the general population. We hypothesize HIV-associated ALS is clinically different from ALS in the absence of HIV in several respects, specifically in that it exhibits on average younger age of onset, slower progression, milder symptomology, and better prognosis. We analyzed records of 322 patients who presented to the ALS Clinic from September 2006 to June 2018, and from that group identified three HIV-positive ALS patients. All three were males with cervical onset classic form of ALS, had been diagnosed with HIV for at least several years, and were undergoing HAART treatment. Each had slower disease progression and younger age of both onset and diagnosis than that described with ALS on average. All three were negative for family history of neurodegenerative disorders. Although limited in its number of patients, this small case series suggests a distinct profile of patients with HIV subsequently diagnosed with ALS. Confirmation with a large case control study or analysis of a large national database may lead to an emerging focus of ALS research related to the modulation of the immune system and its impact on ALS