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Measurements in phantoms are used to predict temperature changes that would occur in vivo for medical implants due to the radio frequency (RF) field in magnetic resonance imaging (MRI). In this study, the impact of concentration of the gelling agent in a saline-based phantom on the RF-induced temperature rise was measured using an apparatus that accurately reproduces the RF environment present in a 1.5-T whole-body MR system. The temperature was measured using fluoroptic thermometry at the electrode and other sites for a deep brain neurostimulation system. The average power deposition in the 30-kg phantom was about 1.5 W/kg. Four phantom formulations were evaluated, using different concentrations of polyacrylic acid (PAA) added to saline solution, with NaCl concentration adjusted to maintain an electrical conductivity near 0.24 S/m. The greatest temperature rises occurred at the electrode, ranging from 16.2 [degrees]C for greatest concentration of PAA to 2.9 [degrees]C for only saline solution. The temperature rise attained the maximal value for sufficient concentration of PAA. Similar behavior was observed in the temperature versus time relationship near a current-carrying resistor, immersed in gel and saline, which was used to model a localized heat source. The temperature rise for insufficient PAA concentration is reduced due to convection of phantom material. In conclusion, an appropriate gelling agent is required to accurately simulate the thermal properties of body tissues for measurements of RF-induced heating with medical implants. Index Terms--Deep brain stimulation, heating, magnetic resonance imaging (MRI), medical implant, radio frequency.

As the coaching industry has grown over the past twenty years, so has the interest in coaching supervision. Although most in the industry agree that supervision plays a valuable role, few agree about what that role should actually be. Even the definition of coaching supervision is widely debated. This paper provides background and history on coaching supervision, an exposition of supervision in the multiple domains, and some areas for future efforts. [ABSTRACT FROM AUTHOR]

BACKGROUND: The declining myogenic potential of aged skeletal muscle is multifactorial. Insufficient satellite cell activity is one factor in this process. Notch and Wnt signaling are involved in various biological processes including orchestrating satellite cell activity within skeletal muscle. These pathways become dysfunctional during the aging process and may contribute to the poor skeletal muscle competency. Phytoecdysteroids are natural adaptogenic compounds with demonstrated benefit on skeletal muscle. AIM: To determine the extent to which a phytoecdysteroid enriched extract from Ajuga turkestanica (ATE) affects Notch and Wnt signaling in aged skeletal muscle. MATERIALS AND METHODS: Male C57BL/6 mice (20 months) were randomly assigned to Control (CT) or ATE treatment groups. Chow was supplemented with either vehicle (CT) or ATE (50 mg/kg/day) for 28 days. Following supplementation, the triceps brachii muscles were harvested and immunohistochemical analyses performed. Components of Notch or Wnt signaling were co-labelled with Pax7, a quiescent satellite cell marker. RESULTS: ATE supplementation significantly increased the percent of active Notch/Pax7+ nuclei (p = 0.005), Hes1/Pax7+ nuclei (p = 0.038), active B-catenin/Pax7+ nuclei (p = 0.011), and Lef1/Pax7+ nuclei (p = 0.022), compared to CT. ATE supplementation did not change the resting satellite cell number. CONCLUSIONS: ATE supplementation in aged mice increases Notch and Wnt signaling in triceps brachii muscle. If Notch and Wnt benefit skeletal muscle, then phytoecdysteroids may provide a protective effect and maintain the integrity of aged skeletal muscle. [ABSTRACT FROM AUTHOR]

Abstract Background Obesity increases the risk of endometrial cancer (EC) and obese EC patients have the highest risk of death among all obesity-associated cancers. However, only two lifestyle interventions targeting this high-risk population have been conducted. In one trial, food disinhibition, as determined by the Three-Factor Eating Questionnaire, decreased post-intervention compared to baseline, suggesting an increase in emotional eating and, potentially, an increase in food related reward. Therefore, we evaluated appetitive behavior using functional magnetic resonance imaging (fMRI) and a visual food task in 8 obese, Stage I/II EC patients before and after a lifestyle intervention (Survivors in Uterine Cancer Empowered by Exercise and a Healthy Diet, SUCCEED), which aimed to improve nutritional and exercise behaviors over 16 group sessions in 6 months using social cognitive theory. Results Congruent to findings in the general obese population, we found that obese EC patients, at baseline, had increased activation in response to high- vs. low-calorie food cues after eating a meal in brain regions associated with food reward (insula, cingulate gyrus; precentral gyrus; whole brain cluster corrected, p Conclusions Our preliminary results suggest behavioral lifestyle interventions may help to reduce high-calorie food reward in obese EC survivors who are at a high-risk of death. To our knowledge, this is the first study to demonstrate such changes.

The HEALthy Brain and Child Development (HBCD) Study, a multi-site prospective longitudinal cohort study, will examine human brain, cognitive, behavioral, social, and emotional development beginning prenatally and planned through early childhood. The acquisition of multimodal magnetic resonance-based brain development data is central to the study's core protocol. However, application of Magnetic Resonance Imaging (MRI) methods in this population is complicated by technical challenges and difficulties of imaging in early life. Overcoming these challenges requires an innovative and harmonized approach, combining age-appropriate acquisition protocols together with specialized pediatric neuroimaging strategies. The HBCD MRI Working Group aimed to establish a core acquisition protocol for all 27 HBCD Study recruitment sites to measure brain structure, function, microstructure, and metabolites. Acquisition parameters of individual modalities have been matched across MRI scanner platforms for harmonized acquisitions and state-of-the-art technologies are employed to enable faster and motion-robust imaging. Here, we provide an overview of the HBCD MRI protocol, including decisions of individual modalities and preliminary data. The result will be an unparalleled resource for examining early neurodevelopment which enables the larger scientific community to assess normative trajectories from birth through childhood and to examine the genetic, biological, and environmental factors that help shape the developing brain., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Tobias Kober and Tom Hilbert are employees of Siemens Healthineers International AG, Switzerland. Yulin Chang is an employee of Siemens Medical Solutions USA Inc. Dan Rettmann and Ralph Noeske are employed by GE HealthCare. Guillaume Gilbert, Yansong Zhao, Sandeep Ganji, and Maarten Versluis are employed by Philips Healthcare. Carina Lucena, Lucky Heisler-Roman, and Dhruman Goradia are employed by PrimeNeuro Inc. Under a license agreement between Philips and the Johns Hopkins University, Dr. van Zijl and the University are entitled to fees related to an imaging device used in the study discussed for publication. Dr. van Zijl also is a paid lecturer for Philips and receives research support from Philips. This arrangement has been reviewed and approved by the Johns Hopkins University in accordance with its conflict of interest policies. Damien Fair is a patent holder on the Framwise Integrated Real-Time Motion Monitoring (FIRMM) software. He is also a co-founder of Turing Medical Technologies, Inc. The nature of this financial interest and the design of the study have been reviewed by two committees at the University of Minnesota. They have put in place a plan to help ensure that this research is not affected by the financial interest. All other authors report no biomedical financial interests or potential conflicts of interest., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Purpose: Our primary purpose was to understand the correlation between pancreas T1-weighted signal intensity ratio (SIR) and T1 relaxation time in children. We also sought to characterize differences in T1 SIR between children without and with pancreatitis., Methods: Retrospective study of patients < 18-years-old. SIR-pancreas:spleen (SIR-PS) and SIR-pancreas:paraspinal muscle (SIR-PM) were generated from T1-weighted gradient recalled echo images. Subdivided by field strength, T1 SIR was correlated (Spearman's) with T1 relaxation time., Results: 220 participants were included, 144 imaged at 1.5T (mean: 11.4 ± 4.2 years) and 76 imaged at 3T (mean: 10.9 ± 4.5 years). At 1.5T, SIR-PS (rho=-0.62, 95% CI: -0.71 to -0.51, p < 0.0001) and SIR-PM (rho=-0.57, 95% CI: -0.67 to -0.45, p < 0.0001) moderately negatively correlated with T1 relaxation time. At 3T, correlations between T1 SIR and T1 relaxation time were moderate (rho=-0.40 to -0.43, p ≤ 0.0003). SIR-PS was significantly different between patient groups at 1.5T (p < 0.0001) with pairwise differences between: normal vs. acute on chronic pancreatitis (1.52 vs. 1.13; p < 0.0001). SIR-PM was also significantly different between groups at 1.5T (p < 0.0001) with differences between: normal vs. acute pancreatitis (1.65 vs. 1.40; p = 0.0006), normal vs. acute on chronic pancreatitis (1.65 vs. 1.18; p < 0.0001), and normal vs. chronic pancreatitis (1.65 vs. 1.52; p = 0.0066). A SIR-PS cut-off of ≤ 1.31 had 44% sensitivity and 95% specificity and SIR-PM cut-off of ≤ 1.53 had 69% sensitivity and 70% specificity for pancreatitis. At 3T, SIR-PS was significantly different between groups (p = 0.033) but without significant pairwise differences., Conclusion: At 1.5T pancreas T1 SIR moderately to strongly correlates with estimated T1 relaxation time and is significantly lower in children with pancreatitis., (© 2024. The Author(s).)

We previously reported interhemispheric structural hyperconnectivity bypassing the corpus callosum in children born extremely preterm (<28 weeks) versus term children. This increased connectivity was positively associated with language performance at 4-6 years of age in our prior work. In the present study, we aim to investigate whether this extracallosal connectivity develops in extremely preterm infants at term equivalent age by leveraging a prospective cohort study of 350 very and extremely preterm infants followed longitudinally in the Cincinnati Infant Neurodevelopment Early Prediction Study. For this secondary analysis, we included only children born extremely preterm and without significant brain injury ( n = 95). We use higher-order diffusion modelling to assess the degree to which extracallosal pathways are present in extremely preterm infants and predictive of later language scores at 22-26 months corrected age. We compare results obtained from two higher-order diffusion models: generalized q-sampling imaging and constrained spherical deconvolution. Advanced MRI was obtained at term equivalent age (39-44 weeks post-menstrual age). For structural connectometry analysis, we assessed the level of correlation between white matter connectivity at the whole-brain level at term equivalent age and language scores at 2 years corrected age, controlling for post-menstrual age, sex, brain abnormality score and social risk. For our constrained spherical deconvolution analyses, we performed connectivity-based fixel enhancement, using probabilistic tractography to inform statistical testing of the hypothesis that fibre metrics at term equivalent age relate to language scores at 2 years corrected age after adjusting for covariates. Ninety-five infants were extremely preterm with no significant brain injury. Of these, 53 had complete neurodevelopmental and imaging data sets that passed quality control. In the connectometry analyses adjusted for covariates and multiple comparisons ( P < 0.05), the following tracks were inversely correlated with language: bilateral cerebellar white matter and middle cerebellar peduncles, bilateral corticospinal tracks, posterior commissure and the posterior inferior fronto-occipital fasciculus. No tracks from the constrained spherical deconvolution/connectivity-based fixel enhancement analyses remained significant after correction for multiple comparisons. Our findings provide critical information about the ontogeny of structural brain networks supporting language in extremely preterm children. Greater connectivity in more posterior tracks that include the cerebellum and connections to the regions of the temporal lobes at term equivalent age appears to be disadvantageous for language development., Competing Interests: The authors report no competing interests., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Guarantors of Brain.)

Background: Pediatric radiologists can identify a liver ultrasound (US) pattern predictive of progression to advanced liver disease. However, reliably discriminating these US patterns remains difficult. Quantitative magnetic resonance imaging (MRI) may provide an objective measure of liver disease in cystic fibrosis (CF)., Objective: The purpose of this study was to determine if quantitative MRI, including MR elastography, is feasible in children with CF and to determine how quantitative MRI-derived metrics compared to a research US., Materials and Methods: A prospective, multi-institutional trial was performed evaluating CF participants who underwent a standardized MRI. At central review, liver stiffness, fat fraction, liver volume, and spleen volume were obtained. Participants whose MRI was performed within 1 year of US were classified by US pattern as normal, homogeneous hyperechoic, heterogeneous, or nodular. Each MRI measure was compared among US grade groups using the Kruskal-Wallis test., Results: Ninety-three participants (51 females [54.8%]; mean 15.6 years [range 8.1-21.7 years]) underwent MRI. MR elastography was feasible in 87 participants (93.5%). Fifty-eight participants had an US within 1 year of MRI. In these participants, a nodular liver had significantly higher stiffness (P<0.01) than normal or homogeneous hyperechoic livers. Participants with a homogeneous hyperechoic liver had a higher fat fraction (P<0.005) than others., Conclusion: MR elastography is feasible in children with CF. Participants with a nodular pattern had higher liver stiffness supporting the US determination of advanced liver disease. Participants with a homogeneous hyperechoic pattern had higher fat fractions supporting the diagnosis of steatosis., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Purpose: Emergency airway management can be associated with a range of complications including long-term neurologic injury and death. We studied the first-pass success rate with emergency airway management in a tertiary care trauma centre. Secondary outcomes were to identify factors associated with first-pass success and factors associated with adverse events peri-intubation., Methods: We performed a single-centre, prospective, observational study of patients ≥ 17 yr old who were intubated in the emergency department (ED), surgical intensive care unit (SICU), medical intensive care unit (MICU), and inpatient wards at our institution. Ethics approval was obtained from the local research ethics board., Results: In a seven-month period, there were 416 emergency intubations and a first-pass success rate of 73.1%. The first-pass success rates were 57.5% on the ward, 66.1% in the intensive care units (ICUs) and 84.3% in the ED. Equipment also varied by location; videolaryngoscopy use was 65.1% in the ED and only 10.6% on wards. A multivariate regression model using the least absolute shrinkage and selection algorithm (LASSO) showed that the odds ratios for factors associated with two or more intubation attempts were location (wards, 1.23; MICU, 1.24; SICU, 1.19; reference group, ED), physiologic instability (1.19), an anatomically difficult airway (1.05), hypoxemia (1.98), lack of neuromuscular blocker use (2.28), and intubator inexperience (1.41)., Conclusions: First-pass success rates varied widely between locations within the hospital and were less than those published from similar institutions, except for the ED. We are revamping ICU protocols to improve the first-pass success rate., (© 2023. Canadian Anesthesiologists' Society.)

Preterm brains commonly exhibit elevated signal intensity in the white matter on T2-weighted MRI at term-equivalent age. This signal, known as diffuse excessive high signal intensity (DEHSI) or diffuse white matter abnormality (DWMA) when quantitatively assessed, is associated with abnormal microstructure on diffusion tensor imaging. However, postmortem data are largely lacking and difficult to obtain, and the pathological significance of DEHSI remains in question. In a cohort of 202 infants born preterm at ≤32 weeks gestational age, we leveraged two newer diffusion MRI models - Constrained Spherical Deconvolution (CSD) and neurite orientation dispersion and density index (NODDI) - to better characterize the macro and microstructural properties of DWMA and inform the ongoing debate around the clinical significance of DWMA. With increasing DWMA volume, fiber density broadly decreased throughout the white matter and fiber cross-section decreased in the major sensorimotor tracts. Neurite orientation dispersion decreased in the centrum semiovale, corona radiata, and temporal lobe. These findings provide insight into DWMA's biological underpinnings and demonstrate that it is a serious pathology., (Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.)

Protein degradation is critical to maintaining cellular homeostasis, and perturbation of the ubiquitin proteasome system leads to the accumulation of protein aggregates. These aggregates are either directed towards autophagy for destruction or sequestered into an inclusion, termed the aggresome, at the centrosome. Utilizing high-resolution quantitative analysis, here, we define aggresome assembly at the centrosome in human cells. Centriolar satellites are proteinaceous granules implicated in the trafficking of proteins to the centrosome. During aggresome assembly, satellites were required for the growth of the aggresomal structure from an initial ring of phosphorylated HSP27 deposited around the centrioles. The seeding of this phosphorylated HSP27 ring depended on the centrosomal proteins CP110, CEP97 and CEP290. Owing to limiting amounts of CP110, senescent cells, which are characterized by the accumulation of protein aggregates, were defective in aggresome formation. Furthermore, satellites and CP110-CEP97-CEP290 were required for the aggregation of mutant huntingtin. Together, these data reveal roles for CP110-CEP97-CEP290 and satellites in the control of cellular proteostasis and the aggregation of disease-relevant proteins., (© 2022. The Author(s).)

Infants born very preterm (VPT) are at high risk of motor impairments such as cerebral palsy (CP), and diagnosis can take 2 years. Identifying in vivo determinants of CP could facilitate presymptomatic detection and targeted intervention. Our objectives were to derive micro- and macrostructural measures of sensorimotor white matter tract integrity from diffusion MRI at term-equivalent age, and determine their association with early diagnosis of CP. We enrolled 263 VPT infants (≤32 weeks gestational age) as part of a large prospective cohort study. Diffusion and structural MRI were acquired at term. Following consensus guidelines, we defined early diagnosis of CP based on abnormal structural MRI at term and abnormal neuromotor exam at 3-4 months corrected age. Using Constrained Spherical Deconvolution, we derived a white matter fiber orientation distribution (fOD) for subjects, performed probabilistic whole-brain tractography, and segmented nine sensorimotor tracts of interest. We used the recently developed fixel-based (FB) analysis to compute fiber density (FD), fiber-bundle cross-section (FC), and combined fiber density and cross-section (FDC) for each tract. Of 223 VPT infants with high-quality diffusion MRI data, 14 (6.3%) received an early diagnosis of CP. The cohort's mean (SD) gestational age was 29.4 (2.4) weeks and postmenstrual age at MRI scan was 42.8 (1.3) weeks. FD, FC, and FDC for each sensorimotor tract were significantly associated with early CP diagnosis, with and without adjustment for confounders. Measures of sensorimotor tract integrity enhance our understanding of white matter changes that antecede and potentially contribute to the development of CP in VPT infants., (© 2021 The Authors. Human Brain Mapping published by Wiley Periodicals LLC.)

Introduction: MRI and MR spectroscopy (MRS) provide early biomarkers of brain injury and treatment response in neonates with hypoxic-ischaemic encephalopathy). Still, there are challenges to incorporating neuroimaging biomarkers into multisite randomised controlled trials. In this paper, we provide the rationale for incorporating MRI and MRS biomarkers into the multisite, phase III high-dose erythropoietin for asphyxia and encephalopathy (HEAL) Trial, the MRI/S protocol and describe the strategies used for harmonisation across multiple MRI platforms., Methods and Analysis: Neonates with moderate or severe encephalopathy enrolled in the multisite HEAL trial undergo MRI and MRS between 96 and 144 hours of age using standardised neuroimaging protocols. MRI and MRS data are processed centrally and used to determine a brain injury score and quantitative measures of lactate and n-acetylaspartate. Harmonisation is achieved through standardisation-thereby reducing intrasite and intersite variance, real-time quality assurance monitoring and phantom scans., Ethics and Dissemination: IRB approval was obtained at each participating site and written consent obtained from parents prior to participation in HEAL. Additional oversight is provided by an National Institutes of Health-appointed data safety monitoring board and medical monitor., Trial Registration Number: NCT02811263; Pre-result., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background and Purpose: Spiral MR imaging has several advantages compared with Cartesian MR imaging that can be leveraged for added clinical value. A multicenter multireader study was designed to compare spiral with standard-of-care Cartesian postcontrast structural brain MR imaging on the basis of relative performance in 10 metrics of image quality, artifact prevalence, and diagnostic benefit., Materials and Methods: Seven clinical sites acquired 88 total subjects. For each subject, sites acquired 2 postcontrast MR imaging scans: a spiral 2D T1 spin-echo, and 1 of 4 routine Cartesian 2D T1 spin-echo/TSE scans (fully sampled spin-echo at 3T, 1.5T, partial Fourier, TSE). The spiral acquisition matched the Cartesian scan for scan time, geometry, and contrast. Nine neuroradiologists independently reviewed each subject, with the matching pair of spiral and Cartesian scans compared side-by-side, and scored on 10 image-quality metrics (5-point Likert scale) focused on intracranial assessment. The Wilcoxon signed rank test evaluated relative performance of spiral versus Cartesian, while the Kruskal-Wallis test assessed interprotocol differences., Results: Spiral was superior to Cartesian in 7 of 10 metrics (flow artifact mitigation, SNR, GM/WM contrast, image sharpness, lesion conspicuity, preference for diagnosing abnormal enhancement, and overall intracranial image quality), comparable in 1 of 10 metrics (motion artifacts), and inferior in 2 of 10 metrics (susceptibility artifacts, overall extracranial image quality) related to magnetic susceptibility ( P < .05). Interprotocol comparison confirmed relatively higher SNR and GM/WM contrast for partial Fourier and TSE protocol groups, respectively ( P < .05)., Conclusions: Spiral 2D T1 spin-echo for routine structural brain MR imaging is feasible in the clinic with conventional scanners and was preferred by neuroradiologists for overall postcontrast intracranial evaluation., (© 2020 by American Journal of Neuroradiology.)

Previous studies have not found structural injury or brain malformations in infants and children with prenatal opioid exposure. As part of an ongoing study evaluating neuroimaging in infants with prenatal opioid exposure, we reviewed structural brain MR imaging in 20 term infants with prenatal opioid exposure and 20 term controls at 4-8 weeks of age. We found that 8 of the 20 opioid-exposed infants had punctate white matter lesions or white matter signal abnormality on structural MR imaging, and 2 of the opioid-exposed infants had a septopreoptic fusion anomaly. No controls had white matter injury or structural malformations. Our findings underscore the importance of clinical neurodevelopmental follow-up and the need for more comprehensive imaging and long-term outcomes research following prenatal opioid exposure., (© 2019 by American Journal of Neuroradiology.)

Background: The use of functional connectivity magnetic resonance imaging (fcMRI) in research involving preterm infants is relatively new, and its feasibility in this population is not fully established. However, fcMRI images reveal functional neural connections that may be useful in establishing the mechanisms of neuroprotective interventions in preterm infants., Objective: The aim of this study was to determine the feasibility of using fcMRI to measure differences in functional neural connections in nursing intervention studies., Methods: A pilot study was conducted as part of a longitudinal, randomized controlled trial (RCT) testing the effect of a feeding intervention on neurodevelopmental and clinical outcomes of preterm infants randomly assigned to one of two groups: a patterned feeding experience (PFE) group and a usual feeding care (UFC) group. The fcMRIs were done at term-equivalent age. Visual, motor, and default mode networks were analyzed., Results: Seven infants were studied (four were in the PFE group, and three were in the UFC group). Participants were selected sequentially from the parent RCT. Clear images were obtained from all participants. Differences were noted among PFE and UFC infants: Infants receiving PFE were hyperconnective in the default mode (caudate, anterior cingulate cortex, and precuneus) and motor networks (middle temporal and middle occipital areas) and hypoconnective in others areas of the default mode (hippocampal and lingual regions) and motor networks (precentral and superior frontal cortices) relative to UFC infants. No differences were noted in visual networks., Discussion: The feasibility of using fcMRI at term-equivalent age in preterm infants who participated in an RCT on the effect of a nursing intervention was shown. Differences in connectivity among infants by group were detected. Further research is needed to show the benefit of fcMRI in studies of preterm infants given the costs of the procedure as well as the uncertain relationship of this early outcome measure to long-term neurodevelopment.

Purpose: This study aims to (i) develop a new high-speed MRI approach by implementing correlation imaging in wavelet-space, and (ii) demonstrate the ability of wavelet-space correlation imaging to image human anatomy with involuntary or physiological motion., Methods: Correlation imaging is a high-speed MRI framework in which image reconstruction relies on quantification of data correlation. The presented work integrates correlation imaging with a wavelet transform technique developed originally in the field of signal and image processing. This provides a new high-speed MRI approach to motion-free data collection without motion monitoring or data segmentation. The new approach, called "wavelet-space correlation imaging", is investigated in brain imaging with involuntary motion and chest imaging with free-breathing., Results: Wavelet-space correlation imaging can exceed the speed limit of conventional parallel imaging methods. Using this approach with high acceleration factors (6 for brain MRI, 16 for cardiac MRI, and 8 for lung MRI), motion-free images can be generated in static brain MRI with involuntary motion and nonsegmented dynamic cardiac/lung MRI with free-breathing., Conclusion: Wavelet-space correlation imaging enables high-speed MRI in the presence of involuntary motion or physiological dynamics without motion monitoring or data segmentation., (© 2014 Wiley Periodicals, Inc.)

Unlabelled: Children with persistent speech disorders (PSD) often present with overt or subtle motor deficits; the possibility that speech disorders and motor deficits could arise from a shared neurological base is currently unknown. Functional MRI (fMRI) was used to examine the brain networks supporting fine motor praxis in children with PSD and without clinically identified fine motor deficits., Methods: This case-control study included 12 children with PSD (mean age 7.42 years, four female) and 12 controls (mean age 7.44 years, four female). Children completed behavioral evaluations using standardized motor assessments and parent reported functional measures. During fMRI scanning, participants completed a cued finger tapping task contrasted passive listening. A general linear model approach identified brain regions associated with finger tapping in each group and regions that differed between groups. The relationship between regional fMRI activation and fine motor skill was assessed using a regression analysis., Results: Children with PSD had significantly poorer results for rapid speech production and fine motor praxis skills, but did not differ on classroom functional skills. Functional MRI results showed that children with PSD had significantly more activation in the cerebellum during finger tapping. Positive correlations between performance on a fine motor praxis test and activation multiple cortical regions were noted for children with PSD but not for controls., Conclusions: Over-activation in the cerebellum during a motor task may reflect a subtle abnormality in the non-speech motor neural circuitry in children with PSD., (Copyright © 2014 Elsevier B.V. All rights reserved.)

DNA double-strand breaks (DSBs) activate a signaling pathway known as the DNA damage response (DDR) which via protein-protein interactions and post-translational modifications recruit signaling proteins, such as 53BP1, to chromatin flanking the lesion. Depletion of the SET8 methyltransferase prevents accumulation of 53BP1 at DSBs; however, this phenotype has been attributed to the role of SET8 in generating H4K20 methylation across the genome, which is required for 53BP1 binding to chromatin, prior to DNA damage. Here, we report that SET8 acts directly at DSBs during the DNA damage response (DDR). SET8 accumulates at DSBs and is enzymatically active at DSBs. Depletion of SET8 just prior to the induction of DNA damage abrogates 53BP1's accumulation at DSBs, suggesting that SET8 acts during DDR. SET8's occupancy at DSBs is regulated by histone deacetylases (HDACs). Finally, SET8 is functionally required for efficient repair of DSBs specifically via the non-homologous end-joining pathway (NHEJ). Our findings reveal that SET8's active role during DDR at DSBs is required for 53BP1's accumulation., (© 2014 The Authors. Published under the terms of the CC BY NC ND 4.0 license.)

Multichannel transmission has the potential to improve many aspects of MRI through a new paradigm in excitation. In this study, multichannel transmission is used to address the effects that variations in B(0) homogeneity have on fat-saturation preparation through the use of the frequency, phase, and amplitude degrees of freedom afforded by independent transmission channels. B(1) homogeneity is intrinsically included via use of coil sensitivities in calculations. A new method, parallel excitation for B-field insensitive fat-saturation preparation, can achieve fat saturation in 89% of voxels with M(z) ≤ 0.1 in the presence of ± 4 ppm B(0) variation, where traditional CHESS methods achieve only 40% in the same conditions. While there has been much progress to apply multichannel transmission at high field strengths, particular focus is given here to application of these methods at 1.5 T., (Copyright © 2012 Wiley Periodicals, Inc.)

Increasing evidence shows that the neural circuits involved in beat perception overlap with motor circuitry even in the absence of overt movement. This study investigated effects of tempo on beat-based processing by combining functional magnetic resonance imaging with a perceptual timing paradigm where participants made simple temporal judgments about short rhythmic sequences. Of central interest were judgments about ambiguous test rhythms where the perceived direction of a timing deviation ("speeding up" vs. "slowing down") depended on the induction of an implied beat. Successful beat induction was reduced when the implied beat was at a slower tempo (1,500 ms) than when it was at a faster tempo (600 ms). Decreased beat induction was accompanied by decreased functional activity in the basal ganglia, premotor and supplementary motor regions, and thalamus. Findings support the conclusion that rhythms presented at a slow tempo reduce involvement of a striato-thalamo-cortico network in beat-based processing., (© 2012 New York Academy of Sciences.)

The goal of this research is to identify the neural response to rewarding food cues before and after eating in overweight/obese (OB) and normal-weight (NW) adults. Based on the previous literature, we expected greater differential activation to food cues vs. objects for OB compared to NW participants both prior to eating and after consumption of a typical lunch. Twenty-two overweight/obese (11 male) and 16 normal-weight (6 male) individuals participated in a functional magnetic resonance imaging task examining neural response to visual cues of high- and low-calorie foods before and after eating. The OB group demonstrated increased neural response to high- and low-calorie foods after eating in comparison to the NW participants in frontal, temporal, and limbic regions. In addition, greater activation in corticolimbic regions (lateral OFC, caudate, anterior cingulate) to high-calorie food cues was evident in OB vs. NW participants after eating. These findings suggest that for OB individuals, high-calorie food cues show sustained response in brain regions implicated in reward and addiction even after eating. Moreover, food cues did not elicit similar brain response after eating in the NW group suggesting that neural activity in response to food cues diminishes with reduced hunger for these individuals., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Purpose: Diffusion tensor imaging (DTI) provides information about magnitude (diffusivity) and directionality (fractional anisotropy, FA) of water diffusion and allows visualization of major white matter tracts. The arcuate fasciculus (AF) connects anterior (Broca's) and posterior (Wernicke's) language areas. We hypothesized that essential language areas identified by direct cortical stimulation would colocalize with areas revealing subcortical connectivity via the AF., Methods: Fourteen patients with pharmacoresistant left hemispheric epilepsy and left hemisphere language dominance underwent invasive evaluations for localization of epileptogenicity and functional mapping. DTI and T1-weighted volumetric magnetic resonance imaging (MRI) scans were coregistered, and subdural grid electrodes identified on postimplantation computed tomography (CT) scans were also coregistered to the MRI scans. The AF was reconstructed from a region lateral to the corona radiata on the FA map. Colocalization, defined as <1 cm between the AF and the electrode positions delineating language cortex, was visually assessed with excellent reliability (Cronbach's alpha = 0.98)., Results: A total of 71 subdural grid contacts were overlying language cortex. Nineteen contacts in eight patients were over Broca's area, 16 of which (84.2%) colocalized with the AF. Fifty-two contacts in 10 patients were over Wernicke's area, with colocalization in 29 patients (55.8%). Colocalization was significantly greater in anterior regions than in posterior regions [chi(2)(1) = 4.850, p < 0.05]., Discussion: The AF, as visualized with DTI, colocalized well with anterior language areas, but less so with posterior language areas, inferring that the latter are more spatially dispersed.

This study was designed to replicate and extend past research examining the impact of the serotonin transporter gene-linked polymorphic region (5HTTLPR) on neural activation during emotional processing. Six women with at least one short allele were compared to six age-matched women with long/long alleles of the 5HTTLPR. Participants were shown 36 positive and 36 negative slides from the International Affective Picture Set, while functional images were acquired using a 4-T magnetic resonance imaging scanner. Although we were unable to replicate past research demonstrating relatively increased amygdala activation among individuals with an "s" allele to negative stimuli, women with an s allele evidenced decreased left fusiform gyrus activation to positive emotional stimuli (as expected). We suggest that women with a short allele may be either less attentive or less "expert" with regard to positive emotional stimuli, and ideas for future research are presented.

Aims: To use Diffusion Tensor Imaging (DTI) to explore structural integrity and connectivity of the uncinate fasciculus (UF) in patients with temporal lobe epilepsy (TLE) and its relationship to memory performance., Methods: DTI and UF reconstruction were performed in 28 patients with TLE (18 left, 10 right) and 10 normal controls. Differences between left and right UF fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values and correlations between DTI measures and memory scores in the TLE groups were computed., Results: In controls, FA was higher in the left than right UF (p < 0.01). In left TLE, FA values were lower and ADC values higher than controls in the left UF and ADC values were higher in the right UF (all p < 0.05). In right TLE, ADCs were higher in the left and right UF compared to controls, and FA was reduced in the left UF (all p < 0.05). In left TLE, ADCs in the left UF were negatively correlated with Auditory Immediate (p < 0.05) and Delayed Memory (p < 0.01). Visual Delayed Memory was positively correlated with reduced FA in the ROI of the right UF and increased radial diffusivities (p < 0.05). No significant correlations were found in right TLE. Thus, DTI values correlated with memory scores in the expected direction in patients with left TLE., Conclusions: Abnormal diffusion measures in the UF ipsilateral to the epileptogenic zone suggest that integrity of the UF is related to memory performance in patients with left TLE. Larger sample sizes are needed to evaluate structure-function correlations further.

Aims: Quantum dots are optical nanocrystals whose in vitro and in vivo use in molecular imaging is expanding rapidly. In comparison with organic fluorophores, quantum dots exhibit desirable properties, such as multiwavelength fluorescence emission, excellent brightness and resistance to photobleaching. Their electron-dense, metallic cores suggest utility in other clinical imaging modalities., Methods: Core-shell zinc sulfide-cadmium telluride quantum dots were studied by magnetic resonance and computed tomography phantoms. Quantum dots were also injected into rat brain, as well as intravenously, using convection-enhanced delivery, prior to animal imaging., Results: Computed tomography studies suggest that current formulations of quantum dots might be imaged in vivo in animals., Conclusions: Used in conjunction with optical imaging techniques, quantum dots have the potential to function as multimodal imaging platforms in vivo. The ability to detect an optical nanoparticle preoperatively with clinical imaging modality offers a distinct advantage to clinicians engaged in image-guided surgical applications.