Mark S Bolding

University of Alabama at Birmingham | UAB · Department of Radiology

Objective Non-invasive light delivery into the brain is needed for in vivo optogenetics to avoid physical damage. An innovative strategy could employ X-ray activation of radioluminescent particles (RLPs) to emit localized light. However, modulation of neuronal or synaptic function by X-ray induced radioluminescence from RLPs has not yet been demons...

Functional magnetic resonance imaging (fMRI) was used to estimate neuronal activity in the primary somatosensory cortex of six participants undergoing cutaneous tactile stimulation on skin areas spread across the entire body. Differences between the accepted somatotopic maps derived from Penfield's work and those generated by this fMRI study were s...

Optogenetics is a widely used tool for studying neural circuits. However, non-invasive methods for light delivery in the brain are needed to avoid physical damage typically caused by intracranial insertion of light guides. An innovative strategy could employ X-ray activation of radioluminescent particles (RLPs) to emit localized light. We previousl...

Optogenetics, the genetic incorporation of light-sensitive proteins such as Channelrhodopsin-2 (ChR2) into target mammalian neurons, has enabled activation, silencing, and receptor subtype specific neuromodulation with high spatiotemporal resolution. However, the essential components of the ontogenetic system require invasive procedures with very f...

A bstract Blood oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI) was used to investigate cortical activity associated with peripheral tactile stimuli in a small cohort of healthy humans. MR-safe automated pneumatic stimulators modeled after the Wartenberg pinwheel were used to generate tactile stimuli at regular intervals...

There is an ongoing need for noninvasive tools to manipulate brain activity with molecular, spatial and temporal specificity. Here we have investigated the use of MRI-visible, albumin-based nanoclusters for noninvasive, localized and temporally specific drug delivery to the rat brain. We demonstrated that IV injected nanoclusters could be deposited...

Background Non‐alcoholic fatty liver disease (NAFLD) has emerged as the most common form of liver disease among adolescents in industrialized countries. While lifestyle intervention remains the hallmark treatment for NAFLD, the most effective dietary strategy to reverse NAFLD in children is unknown. Objective The objective of this study was to det...

The eye may act as a surrogate for the brain in response to head acceleration during an impact. This paper reports the latest demonstration of the correlation between the passive human eye accelerations and the brain accelerations under head impacts using a model eye/brain/skull phantom. Experiments investigating rotational and linear accelerations...

We report the finding that C. elegans display X-ray avoidance behavior at high but well tolerated doses, and that this behavior appears to require LITE-1, a gustatory receptor that has been implicated in UV avoidance behavior. We recorded acute behavioral responses of wild-type worms to increasing intensities of X-ray stimulation and found a positi...

There is an ongoing need for noninvasive tools to manipulate brain activity with molecular, spatial and temporal specificity. Here we have investigated the use of MRI-visible, albumin-based nanoclusters for noninvasive, localized and temporally specific drug delivery to the rat brain. We demonstrated that IV injected nanoclusters could be deposited...

Background—Non-alcoholic fatty liver disease (NAFLD) is the most common liver disorder among children in the developed world and can progress to cirrhosis, hepatocellular carcinoma, and liver failure. No evidence-based dietary guidelines exist on the most effective diet prescription to treat NAFLD. Objective—To compare the effect of a carbohydrate...

Ultrasmall iron oxide nanoparticles (USIONPs) (< 4 nm) have recently attracted significant attention because of their potential as positive T1 magnetic resonance imaging (MRI) contrast agent contrary to larger superparamagnetic iron oxide nanoparticles (> 6 nm) which act as negative T2 MRI contrast agent. However, studies on the cellular uptake beh...

The current effort demonstrates that lutetium oxyorthosilicate doped with 1-10% cerium (Lu2SiO5:Ce, LSO:Ce) radioluminescent particles can be coated with a single dye or multiple dyes and generate an effective energy transfer between the core and dye(s) when excited via x-rays. LSO:Ce particles were surface modified with an alkyne modified naphthal...

Introduction This randomised controlled trial (RCT) examines treadmill walking exercise training effects on learning and memory performance, hippocampal volume, and hippocampal resting-state functional connectivity in persons with multiple sclerosis (MS) who have objective impairments in learning new information. Methods and analysis Forty fully a...

In article number 1800051, Jason Warram, Yuping Bao, Eugenia Kharlampieva and co‐workers demonstrate ultrasound‐triggered drug release from MRI‐visible polymeric microcapsules. Iron oxide nanoparticles are attached to the microcapsules which provide imaging contrast rivaling commercial contrast agents at a fraction of the metal concentration. The e...

Although imaging‐guided drug delivery represents a noninvasive alternative to both surgical resection and systemic methods, it has seen limited clinical use due to the potential toxicity and fast clearance of currently available imaging agents. Herein, we introduce theranostic biocompatible microcapsules as efficient contrast‐enhanced imaging agent...

Focused ultrasound combined with bubble-based agents serves as a non-invasive way to open the blood-brain barrier (BBB). Passive acoustic detection was well studied recently to monitor the acoustic emissions induced by the bubbles under ultrasound energy, but the ability to perform reliable BBB opening with a real-time feedback control algorithm ha...

Restenosis by neointimal hyperplasia is still an ongoing concern in endovascular surgery. Slowing vascular smooth muscle cell (VSMC) proliferation by reversing the phenotype change, would allow vessel healing and re-endotheliazation. To accomplish this, we have developed heparin-coated magnetic nanoparticles for targeted drug therapy of neointimal...

Background: Non-alcoholic fatty liver disease (NAFLD) is the most common liver disorder among children in the developed world and can progress to cirrhosis, hepatocellular carcinoma, and liver failure. No evidence-based dietary guidelines exist on the most effective diet prescription to treat NAFLD. Objective: To compare the effect of a carbohyd...

The eye may act as a surrogate for the brain in response to head acceleration during an impact. Passive eye movements in a dynamic system are sensed by microelectromechanical systems (MEMS) inertial measurement units (IMU) in this paper. The technique is validated using a three-dimensional printed scaled human skull model and on human volunteers by...

Iron oxide nanoparticles with extremely low dimensions have recently been explored as positive (T1) contrast agent for magnetic resonance imaging (MRI). However, their small sizes lead to fast renal clearance and limit their use in elongated in vivo tracking or therapy monitoring. In this paper, we present a state of art approach to forming nanoclu...

Purpose: To develop a portable perfusion phantom and validate its utility in quantitative dynamic contrast-enhanced magnetic resonance imaging of the abdomen. Methods: A portable perfusion phantom yielding a reproducible contrast enhancement curve (CEC) was developed. A phantom package including perfusion and static phantoms were imaged simultan...

Alzheimer’s disease (AD), a debilitating neurodegenerative illness, is characterized by neuronal cell loss, mental deficits, and abnormalities in several neurotransmitter and protein systems. AD is also associated with visual disturbances, but their causes remain unidentified. We hypothesize that the visual disturbances stem from retinal changes, p...

Recent research efforts about iron oxide nanoparticles has focused on the development of iron oxide-based T1 contrast agents for magnetic resonance imaging (MRI), such as ultrasmall iron oxide nanospheres (USNPs <4 nm) and ultrathin nanowires (NW, diameter <4 nm). In this paper, we report the cellular uptake behaviors of these two types of ultrasma...

A growing body of evidence suggests glutamate excess in schizophrenia and that N-methyl-d-aspartate receptor (NMDAR) hypofunction on γ-aminobutyric acid (GABA) interneurons disinhibiting pyramidal cells may be relevant to this hyperglutamatergic state. To better understand how NMDAR hypofunction affects the brain, we used magnetic resonance spectro...

Purpose:To test spatial and dosimetric accuracy of small cranial target irradiation based on 1.5 T MRI scans using static arcs with MLC-defined fields Methods:A plastic (PMMA) phantom simulating a small brain lesion was mounted on a GammaKnife headframe equipped with MRI localizer. The lesion was a 3 mm long, 3.175 mm diameter cylindrical cavity fi...

Importance Central airway collapse greater than 50% of luminal area during exhalation (expiratory central airway collapse [ECAC]) is associated with cigarette smoking and chronic obstructive pulmonary disease (COPD). However, its prevalence and clinical significance are unknown.Objective To determine whether ECAC is associated with respiratory mo...

It is currently thought that the primate oculomotor system has evolved distinct but interrelated subsystems to generate different types of visually guided eye movements (e.g., saccades/smooth pursuit/vergence). Although progress has been made in elucidating the neural basis of these movement types, no study to date has investigated all three moveme...

??????Near-field antennas are critical to the performance of magnetic resonance imaging (MRI). Unlike conventional antennas designed for far-field radiation, there are rather strict geometric requirements, such as conformity and symmetry. We present a fast-prototyping approach that combines accurate electromagnetic simulation and 3-D printing techn...

Bevacizumab is widely used for treatment of high-grade gliomas and other malignancies. Because bevacizumab has been shown to be associated with neurocognitive decline, this study is designed to investigate whether prolonged treatment with bevacizumab is also associated with brain atrophy. We identified 12 high-grade glioma patients who received bev...

In this paper, a highly innovative concept of using ultrathin iron oxide nanowhiskers as a positive (T1) contrast agent for magnetic resonance imaging (MRI) is demonstrated. Iron oxide nanowhiskers with dimensions of approximately 2 nm × 20 nm are synthesized by heating an iron oleate/oleylamine complex under 150 °C. These nanostructures have very...

Previous studies have shown that smooth pursuit eye movements are impaired in patients with schizophrenia. However, under normal viewing conditions, targets move not only in the frontoparallel plane but also in depth, and tracking them requires both smooth pursuit and vergence eye movements. Although previous studies in humans and non-human primate...

Medication management in schizophrenia is a lengthy process, as the lack of clinical response can only be confirmed after at least four weeks of antipsychotic treatment at a therapeutic dose. Thus there is a clear need for the discovery of biomarkers that have the potential to accelerate the management of treatment. Using resting-state functional M...

Introduction: Antipsychotic drugs (APDs) alleviate some of the symptoms of schizophrenia, but up to 30% of patients do not respond to these drugs (Harrow, 1997). Currently, treatment responders and non-responders can only be identified after lengthy medication trials. Imaging research in schizophrenia has revealed altered functional connectivity (F...

Background: Studies have shown a negative association between value of the future (preference for long-term vs. short-term rewards) and harmful addictive behaviors; however, research in the area of preventive behaviors is limited and has shown conflicting results. Objectives: The primary objectives were: (1) to examine the association among valu...

To evaluate changes in functional connectivity as a result of treatment with antipsychotic drugs (APDs) in subjects with schizophrenia (SZ), we identified a limited number of regions that have been implicated in the mechanism of action of APDs and that are part of a neuronal network known to be modulated by dopamine (DA). These regions consisted of...

Raw histology images for the paper "Magnetic Transfer Contrast Accurately Localizes Substantia Nigra Confirmed by Histology."

Individuals with schizophrenia (SZ) have been reported to exhibit a higher prevalence of convergence insufficiency (CI) than the “normal” adult population. The purpose of this study was to determine if individuals with SZ exhibit clinical signs of CI and to determine if the Convergence Insufficiency Symptom Survey (CISS) is an effective instrument...

Antipsychotic drugs (APDs) alleviate some of the symptoms of schizophrenia, but up to 30% of patients do not respond; it is not currently possible to distinguish these patients from those who will respond to treatment. Imaging research in schizophrenia has revealed altered functional connectivity (FC) between brain regions, thought to reflect chang...

Background: Magnetic resonance imaging (MRI) has multiple contrast mechanisms. Like various staining techniques in histology, each contrast type reveals different information about the structure of the brain. However, it is not always clear how structures visible in MRI correspond to structures previously identified by histology. The purpose of th...

Studies have shown that individuals with schizophrenia suffer from memory impairments. In this study, we combined proton magnetic resonance spectroscopy (¹H-MRS) and functional magnetic resonance imaging (fMRI) to clarify the neurobiology of memory deficits in schizophrenia. We used single-voxel MRS acquired in the left hippocampus and fMRI during...

The purpose of this study was to determine where stretch-shortening cycle (SSC) potentiation of force, power, velocity, and acceleration occurs across the concentric phase of ballistic leg presses. Second, we examined the influence of late eccentric phase force and length of the amortization phase on potentiated concentric phase performance variabl...

Models of addiction include abnormalities in parts of the brain involving executive function/inhibitory control. Although previous studies have reported evidence of structural abnormalities in cocaine-dependent individuals, none have specifically targeted the homeless. The present preliminary study investigated brain structure in such an understudi...

A goal of this study was to evaluate the function of the anterior cingulate cortex (ACC) and of the dorsolateral prefrontal cortex (DLPFC) in medicated patients with schizophrenia (SZ), a small group of first-degree relatives, and healthy controls using a visual delayed match-to-sample task in conjunction with functional magnetic resonance imaging...

Spin-echo signals allow separate measurements of irreversible and reversible relaxation rates in MRI. A spin-echo version of single-shot parameter assessment by retrieval from signal encoding (SE-SS-PARSE) method has been developed to quantitatively and accurately map transverse magnetization magnitude, frequency, irreversible and reversible relaxa...

Neuroimaging and electrophysiologic studies have consistently provided evidence of impairment in anterior cingulate cortex/medial frontal cortex function in people with schizophrenia. In this study, we sought to clarify the nature of this abnormality by combining proton magnetic resonance spectroscopy (1H-MRS) with functional magnetic resonance ima...

Adaptation to a sustained stimulus is an important phenomenon in psychophysical experiments. When studying the response to an experimental task, the investigator has to account for the change in perceived stimulus intensity with repeated stimulus application and, if the stimulus is sustained, for the change in intensity during the presentation. An...

Introduction. Although a high proportion of the motion selective cells in non-human primate motion areas are disparity-selective, there is no convincing evidence for cells specific to stereomotion-in-depth, and the neural basis of stereomotion processing remains obscure. However, recent fMRI studies in humans (Likova and Tyler, 2007) have revealed...

Lower extremity torque steadiness has been shown to be an independent predictor of functional performance in older women. Hip muscle function is crucial for many types of activities of daily living, yet existing studies investigating torque steadiness for lower extremities are limited to assessing steadiness at the knee and ankle. The purpose of th...

As a variant of Single-Shot Parameter Assessment by Retrieval from Signal Encoding, Velocity Single-Shot Parameter Assessment by Retrieval from Signal Encoding, a single-shot imaging method, has been developed to realize fast and straightforward flow quantification by solving inverse problems. A robust signal model, including its local magnetizatio...