Development of Anatomical and Functional Magnetic Resonance Imaging Measures of Alzheimer Disease

Alzheimer disease is considered to be a progressive neurodegenerative condition, clinically characterized by cognitive dysfunction and memory impairments. Incorporating imaging biomarkers in the early diagnosis and monitoring of disease progression is increasingly important in the evaluation of novel treatments. The purpose of the work in this thesis was to develop and evaluate novel structural and functional biomarkers of disease to improve Alzheimer disease diagnosis and treatment monitoring. Our overarching hypothesis is that magnetic resonance imaging methods that sensitively measure brain structure and functional impairment have the potential to identify people with Alzheimer’s disease prior to the onset of cognitive decline. Since the hippocampus is considered to be one of the first brain structures affected by Alzheimer disease, in our first study a reliable and fully automated approach was developed to quantify medial temporal lobe atrophy using magnetic resonance imaging. This measurement of medial temporal lobe atrophy showed differences (pnovel biomarker of brain activity was developed based on a first-order textural feature of the resting state functional magnetic resonance imagining signal. The mean brain activity metric was shown to be significantly lower (pp18F labeled fluorodeoxyglucose positron emission tomography. In the final study, we examine whether combined measures of gait and cognition could predict medial temporal lobe atrophy over 18 months in a small cohort of people (N=22) with mild cognitive impairment. The results showed that measures of gait impairment can help to predict medial temporal lobe atrophy in people with mild cognitive impairment. The work in this thesis contributes to the growing evidence the specific magnetic resonance imaging measures of brain structure and function can be used to identify and monitor the progression of Alzheimer’s disease. Continued refinement of these methods, and larger longitudinal studies will be needed to establish whether the specific metrics of brain dysfunction developed in this thesis can be of clinical benefit and aid in drug development

Accurate Real Time Localization Tracking in A Clinical Environment using Bluetooth Low Energy and Deep Learning

Deep learning has started to revolutionize several different industries, and the applications of these methods in medicine are now becoming more commonplace. This study focuses on investigating the feasibility of tracking patients and clinical staff wearing Bluetooth Low Energy (BLE) tags in a radiation oncology clinic using artificial neural networks (ANNs) and convolutional neural networks (CNNs). The performance of these networks was compared to relative received signal strength indicator (RSSI) thresholding and triangulation. By utilizing temporal information, a combined CNN+ANN network was capable of correctly identifying the location of the BLE tag with an accuracy of 99.9%. It outperformed a CNN model (accuracy = 94%), a thresholding model employing majority voting (accuracy = 95%), and a triangulation classifier utilizing majority voting (accuracy = 95%). Future studies will seek to deploy this affordable real time location system in hospitals to improve clinical workflow, efficiency, and patient safety

Comparison of blood lead levels between oral and inhalation opium addicts and its relationship with hematological parameters

Background and objectives: The current study aimed at comparing the level of blood Pb in oral and inhalation opium addicts and its relationship with hematological parameters. Materials and method: For this purpose, a total of 166 patients (83 addicts as the case and 83 non-addicts as the control groups) were enrolled in the study. A venous blood sample was taken from all the subjects in order to determine the serum level of Pb, iron (Fe), and other hematological parameters. In addition, the clinical and demographic status of the subjects were recorded and analyzed using appropriate statistical methods. Results: Among the enrolled patients, 48 were oral and 35 were the inhalation opium consumers. Oral and inhalation opium addict groups had higher levels of blood Pb compared with the control group (F = 131.13, P <0.001). There was no significant difference between oral and inhalation addict groups (P >0.05). More investigations showed a negative relationship between the blood levels of Pb, and those of Fe, hemoglobin(HB), hematocrit (HCT), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), and positive relationship with red cell distribution width (RDW) (P >0.05). Conclusion: The results showed that the serum level of Pb was associated with those of Fe and Hb in opium addicts in comparison with the controls. These changes had a significant effect on other hematological parameters in the case group in comparison with the control group. However, there was no significant relationship between different forms of opium us

Pore-Scale Dynamics of Liquid CO\u3csub\u3e2\u3c/sub\u3e–Water Displacement in 2D Axisymmetric Porous Micromodels Under Strong Drainage and Weak Imbibition Conditions: High-Speed μPIV Measurements

Resolving pore-scale transient flow dynamics is crucial to understanding the physics underlying multiphase flow in porous media and informing large-scale predictive models. Surface properties of the porous matrix play an important role in controlling such physics, yet interfacial mechanisms remain poorly understood, in part due to a lack of direct observations. This study reports on an experimental investigation of the pore-scale flow dynamics of liquid CO2 and water in two-dimensional (2D) circular porous micromodels with different surface characteristics employing high-speed microscopic particle image velocimetry (μPIV). The design of the micromodel minimized side boundary effects due to the limited size of the domain. The high-speed μPIV technique resolved the spatial and temporal dynamics of multiphase flow of CO2 and water under reservoir-relevant conditions, for both drainage and imbibition scenarios. When CO2 displaced water in a hydrophilic micromodel (i.e., drainage), unstable capillary fingering occurred and the pore flow was dominated by successive pore-scale burst events (i.e., Haines jumps). When the same experiment was repeated in a nearly neutral wetting micromodel (i.e., weak imbibition), flow instability and fluctuations were virtually eliminated, leading to a more compact displacement pattern. Energy balance analysis indicates that the conversion efficiency between surface energy and external work is less than 30%, and that kinetic energy is a disproportionately smaller contributor to the energy budget. This is true even during a Haines jump event, which induces velocities typically two orders of magnitude higher than the bulk velocity. These novel measurements further enabled direct observations of the meniscus displacement, revealing a significant alteration of the pore filling mechanisms during drainage and imbibition. While the former typically featured burst events, which often occur only at one of the several throats connecting a pore, the latter is typically dominated by a cooperative filling mechanism involving simultaneous invasion of a pore from multiple throats. This cooperative filling mechanism leads to merging of two interfaces and releases surface energy, causing instantaneous high-speed events that are similar, yet fundamentally different from, burst events. Finally, pore-scale velocity fields were statistically analyzed to provide a quantitative measure of the role of capillary effects in these pore flows

Prevalence of metabolic syndrome in Qazvin Metabolic Diseases study (QMDs), Iran: A comparative analysis of six deinitions

objective. he aim of the present study was to compare the prevalence of metabolic syndrome (MS) according to six deinitions and evaluate the agreement between them in an urban sample in Qazvin, Iran. Methods. In a cross sectional study, 529 men and 578 women in age of 20-78 years were attended from September 2010 to April 2011 in Qazvin, Iran. Standardized measurements were available for waist circumference, blood pressure, fasting serum high-density lipoprotein cholesterol, triglycerides, glucose, and insulin. he diagnostic criteria proposed by World Health Organization (WHO), National cholesterol education program third Adult Treatment Panel (ATPIII 2001, 2004), International Diabetes Federation (IDF), American Heart Association/National Heart, Lung and Blood Institute (AHA/NHLBI), and new Joint Interim Societies (JIS) were applied. he degree of agreement between diferent deinitions was assessed by kappa statistic. Results. he prevalence of MS was found to be 28% (WHO), 26.2% (ATPIII 2001), 30.6% (ATPIII 2004), 34.2% (IDF), 33% (AHA/NHLBI), and 39.3% (JIS). With regards to the gender, the prevalence of MS according to ATPIII 2001 and IDF was signiicantly greater in women than men. However, using other deinitions, the prevalence of MS was similar in both genders. he agreement of JIS criteria with IDF and AHA/NHLBI deinitions was excellent (IDF: 0.902; AHA/NHLBI: 0.862), while the agreement of IDF criteria with ATPIII 2004 and AHA/NHLBI was good (ATPIII 2004:0.719; AHA/NHLBI: 0.756). Conclusions. Although JIS deinition resulted in a higher prevalence of MS than other deinitions, an excellent agreement has been seen between these criteria. Widespread acceptance of JIS deinition may lead to management and therapy in a greater part of the population. Keywords: agreement, insulin resistance, deinitions, prevalence, metabolic syndrome, waist circumferenc

Is Vitamin D Deficiency associated with Non Specific Musculoskeletal Pain?

Backgrounds: Vitamin D deficiency is common worldwide, including Iran. It has been suggested that vitamin D deficiency is associated with non-specific musculoskeletal pain. The aim of this study is evaluation of the association of musculoskeletal pain with vitamin D deficiency and the response of the patients to vitamin D supplementation. Materials and Methods: sixty two adult patients with chief complaint of musculoskeletal pain were enrolled in the study. Serum concentrations of 25(OH)D, Calcium, Phosphate, Alkaline Phosphatase and PTH were determined. If there was vitamin D deficiency, oral vitamin D supplementation was given. Assessment of pain and its response to therapy was carried out using Visual Assessment Score (VAS). SPSS software version 15.0 was used for statistical analyses. Findings: Most of the patients (95.4%) had vitamin D deficiency. Pain in 53 patients (85.5%) with responded to the proposed treatment. In responder group post treatment vitamin D concentration was significantly higher than non responder group (60.6±27.6and 39.2±9.6 nmol/l respectively, p<0.01) pretreatment vitamin D and minerals concentrations and pain characteristics did not have significant differences in responder and non responder group. Conclusion: Treatment with vitamin D can relieve the pain in majority of the patients with vitamin D deficiency. Lack of response can be due to insufficient increase in serum vitamin D concentration.Physiologic differences of gastrointestinal vitamin D absorption, differences of body mass indexes, and noncompliance could be potential causes for this issue. Reassessment of serum 25(OH)D concentration is recommended in nonresponsive patients. Keywords: Vitamin D deficiency, musculoskeletal pain, Vitamin D supplementation, Ira

Spontaneous low frequency BOLD signal variations from resting-state fMRI are decreased in Alzheimer disease

Previous studies have demonstrated altered brain activity in Alzheimer\u27s disease using task based functional MRI (fMRI), network based resting-state fMRI, and glucose metabolism from 18 F fluorodeoxyglucose-PET (FDG-PET). Our goal was to define a novel indicator of neuronal activity based on a first-order textural feature of the resting state functional MRI (RS-fMRI) signal. Furthermore, we examined the association between this neuronal activity metric and glucose metabolism from F-18 FDG-PET. We studied 15 normal elderly controls (NEC) and 15 probable Alzheimer disease (AD) subjects from the AD Neuroimaging Initiative. An independent component analysis was applied to the RS-fMRI, followed by template matching to identify neuronal components (NC). A regional brain activity measurement was constructed based on the variation of the RS-fMRI signal of these NC. The standardized glucose uptake values of several brain regions relative to the cerebellum (SUVR) were measured from partial volume corrected FDG-PET images. Comparing the AD and NEC groups, the mean brain activity metric was significantly lower in the accumbens, while the glucose SUVR was significantly lower in the amygdala and hippocampus. The RS-fMRI brain activity metric was positively correlated with cognitive measures and amyloid beta 1-42 cerebral spinal fluid levels; however, these did not remain significant following Bonferroni correction. There was a significant linear correlation between the brain activity metric and the glucose SUVR measurements. This proof of concept study demonstrates that this novel and easy to implement RS-fMRI brain activity metric can differentiate a group of healthy elderly controls from a group of people with AD