Biomedical Engineering and Bioengineering | Open Access Articles

Pattern Discovery In Brain Imaging Genetics Via Scca Modeling With A Generic Non-Convex Penalty, Lei Du, Kefei Liu, Xiaohui Yao, Jingwen Yan, Shannon L. Risacher, Junwei Han, Lei Guo, Andrew J. Saykin, Li Shen, Michael W. Weiner, Paul Aisen, Ronald Petersen, Clifford R. Jack, William Jagust, John Q. Trojanowki, Arthur W. Toga, Laurel Beckett, Robert C. Green, John Morris, Leslie M. Shaw, Zaven Khachaturian, Greg Sorensen, Maria Carrillo, Lew Kuller, Marc Raichle, Steven Paul, Peter Davies, Howard Fillit, Franz Hefti, David Holtzman, Charles D. Smith, Gregory Jicha, Peter A. Hardy, Partha Sinha, Elizabeth Oates, Gary Conrad

Neurology Faculty Publications

Brain imaging genetics intends to uncover associations between genetic markers and neuroimaging quantitative traits. Sparse canonical correlation analysis (SCCA) can discover bi-multivariate associations and select relevant features, and is becoming popular in imaging genetic studies. The L1-norm function is not only convex, but also singular at the origin, which is a necessary condition for sparsity. Thus most SCCA methods impose ℓ₁-norm onto the individual feature or the structure level of features to pursuit corresponding sparsity. However, the ℓ₁-norm penalty over-penalizes large coefficients and may incurs estimation bias. A number of non-convex penalties are proposed to reduce …

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White Matter Hyperintensity Associations With Cerebral Blood Flow In Elderly Subjects Stratified By Cerebrovascular Risk, Ahmed A. Bahrani, David K. Powell, Guoqiang Yu, Eleanor S. Johnson, Gregory A. Jicha, Charles D. Smith

Biomedical Engineering Faculty Publications

Objective: This study aims to add clarity to the relationship between deep and periventricular brain white matter hyperintensities (WMHs), cerebral blood flow (CBF), and cerebrovascular risk in older persons. Methods: Deep white matter hyperintensity (dWMH) and periventricular white matter hyperintensity (pWMH) and regional gray matter (GM) and white matter (WM) blood flow from arterial spin labeling were quantified from magnetic resonance imaging scans of 26 cognitively normal elderly subjects stratified by cerebrovascular disease (CVD) risk. Fluidattenuated inversion recovery images were acquired using a high-resolution 3-dimensional (3-D) sequence that reduced partial volume effects seen with slicebased techniques. Results: dWMHs but not …

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Cold Atmospheric Plasma, A Novel Promising Anti-Cancer Treatment Modality., Dayun Yan, Jonathan H Sherman, Michael Keidar

Neurological Surgery Faculty Publications

Over the past decade, cold atmospheric plasma (CAP), a near room temperature ionized gas has shown its promising application in cancer therapy. Two CAP devices, namely dielectric barrier discharge and plasma jet, show significantly anti-cancer capacity over dozens of cancer cell lines in vitro and several subcutaneous xenograft tumors in vivo. In contrast to conventional anti-cancer approaches and drugs, CAP is a selective anti-cancer treatment modality. Thus far establishing the chemical and molecular mechanism of the anti-cancer capacity of CAP is far from complete. In this review, we provide a comprehensive introduction of the basics of CAP, state of the …

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Studying The Optimal Scheduling For Controlling Prostate Cancer Under Intermittent Androgen Suppression, Sunil K. Dhar, Hans R. Chaudhry, Bruce G. Bukiet, Zhiming Ji, Nan Gao, Thomas W. Findley

Harvard University Biostatistics Working Paper Series

This retrospective study shows that the majority of patients’ correlations between PSA and Testosterone during the on-treatment period is at least 0.90. Model-based duration calculations to control PSA levels during off-treatment are provided. There are two pairs of models. In one pair, the Generalized Linear Model and Mixed Model are both used to analyze the variability of PSA at the individual patient level by using the variable “Patient ID” as a repeated measure. In the second pair, Patient ID is not used as a repeated measure but additional baseline variables are included to analyze the variability of PSA.

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Resting State Functional Network Disruptions In A Kainic Acid Model Of Temporal Lobe Epilepsy., Ravnoor Singh Gill, Seyed M Mirsattari, L Stan Leung

Physiology and Pharmacology Publications

We studied the graph topological properties of brain networks derived from resting-state functional magnetic resonance imaging in a kainic acid induced model of temporal lobe epilepsy (TLE) in rats. Functional connectivity was determined by temporal correlation of the resting-state Blood Oxygen Level Dependent (BOLD) signals between two brain regions during 1.5% and 2% isoflurane, and analyzed as networks in epileptic and control rats. Graph theoretical analysis revealed a significant increase in functional connectivity between brain areas in epileptic than control rats, and the connected brain areas could be categorized as a limbic network and a default mode network (DMN). The …

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Neurology Faculty Publications

White Matter Hyperintensity Associations With Cerebral Blood Flow In Elderly Subjects Stratified By Cerebrovascular Risk, Ahmed A. Bahrani, David K. Powell, Guoqiang Yu, Eleanor S. Johnson, Gregory A. Jicha, Charles D. Smith

Biomedical Engineering Faculty Publications

Cold Atmospheric Plasma, A Novel Promising Anti-Cancer Treatment Modality., Dayun Yan, Jonathan H Sherman, Michael Keidar

Neurological Surgery Faculty Publications

Studying The Optimal Scheduling For Controlling Prostate Cancer Under Intermittent Androgen Suppression, Sunil K. Dhar, Hans R. Chaudhry, Bruce G. Bukiet, Zhiming Ji, Nan Gao, Thomas W. Findley

Harvard University Biostatistics Working Paper Series

Resting State Functional Network Disruptions In A Kainic Acid Model Of Temporal Lobe Epilepsy., Ravnoor Singh Gill, Seyed M Mirsattari, L Stan Leung

Physiology and Pharmacology Publications