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1.  Computer diagnosis in cardiology 
This article reports upon the emergence of a novel cognitive, computer-based technology which may lead to significantly improved methods of cardiological diagnosis and a rapid and inexpensive method of cardiological screening.
The technology ‘Virtual Scanning’ illustrates how, in blood, the reaction of proteins and their reactive substrates releases light; that the colour and intensity of this bioluminescence is unique to each reaction and it's rate; and that the development of pathologies influence cognition and visual perception. This illustrates that the function of the autonomic nervous system is linked to that of the physiological systems and that the rate of biochemical reactions, and the progression of disease, can be measured by a cognitive test procedure and used as an indication of the disease(s) affecting heart function.
The article discusses the limitations of the conventional biomarker technique, and the potential value of non-invasive cognitive techniques, such as Virtual Scanning, to the medical practitioner. Finally, it discusses how the ability of Virtual Scanning to diagnose disease from its presymptomatic origins may lead to improved diagnostic accuracy and significantly reduced costs.
PMCID: PMC3364659  PMID: 22666689
Computer diagnosis; autonomic nervous system; visual perception; virtual scanning; mathematical modeling; physiological systems
2.  Demonstration 
PMCID: PMC2181748  PMID: 19993313
3.  Development and Characterization of a Voltammetric Carbon-fiber Microelectrode pH Sensor 
This work describes the development and characterization of a modified carbon-fiber microelectrode sensor capable of measuring real-time physiological pH changes in biological microenvironments. The reagentless sensor was fabricated under ambient conditions from voltammetric reduction of the diazonium salt Fast Blue RR onto a carbon-fiber surface in aprotic media. Fast-scan cyclic voltammetry was used to probe redox activity of the p-quinone moiety of the surface-bound molecule as a function of pH. In vitro calibration of the sensor in solutions ranging from pH 6.5 to 8.0 resulted in a pH-dependent anodic peak potential response. Flow-injection analysis was used to characterize the modified microelectrode, revealing sensitivity to acidic and basic changes discernable to 0.005 pH units. Furthermore, the modified electrode was used to measure dynamic in vivo pH changes evoked during neurotransmitter release in the central nervous system of the microanalytical model organism Drosophila melanogaster.
PMCID: PMC4774550  PMID: 20380393
4.  Strategies for Enrollment of African Americans into Cancer Genetic Studies 
The enrollment of ethnically diverse populations in genetic and genomic research is vital to the parity of benefits resulting from research with biological specimens. Herein, we discuss strategies that may effectively improve the recruitment of African Americans into genetics studies. Specifically, we show that engaging physicians, genetic counselors, and community members is essential to enrolling participants into genetic studies. We demonstrate the impact of utilizing African American genetic counselors on study enrollment rates and implementing a two-page consent form that improved on a lengthy and inefficient consenting process. Lastly, we provided participants with the option of donating saliva instead of blood for study purposes. Descriptive statistics were used. Using the aforementioned strategies, recruitment goals for the Genetic Basis of Breast Cancer Subtype Study at Howard University (HU) were met. Our overall results yielded 182 participants in 18 months. Recruitment strategies that involve the engagement of physicians, genetic counselors, and community members may help researchers increase the enrollment of ethnically diverse and hard-to-reach participants into genetic studies.
PMCID: PMC4254900  PMID: 24882437
African Americans; Genetic counseling; Cancer genetic research; Research strategies
5.  Measles Vaccine Coverage and Series Completion among Children 0 to 8 Years of Age in Tianjin, China 
The World Health Organization (WHO) targeted China for measles elimination by 2012. While China made significant progress, transmission continues, warranting examination of China's measles vaccination program. The WHO recommends that children receive at least two doses of a measles containing vaccine (MCV) to ensure protection. In Tianjin, China, MCV is given in three doses; 8 months (MV), 18-24 months (MMR-1), and 5 years (MMR-2). MMR-2 is important because of the young age for MV administration. This study describes MCV coverage, assesses administration timeliness, and evaluates completion of the MCV series for children living in Tianjin, China.
In July 2012, immunization records were selected from Tianjin's Immunization Information Management System. Records were abstracted for children born from 2004 to 2011, who were age 8 months or older. Descriptive statistics characterized the study population and assessed timeliness and coverage for each MCV dose.
We examined records of 205,982 children living in Tianjin, China. Among children who were age-appropriate for each vaccine, 98.6% received MV, 97.6% received MMR-1, and 76.9% received MMR-2. Of the children who were old enough to receive MMR-2, 78.8% received the complete series, and 71.6% of children were fully immunized for measles by age 6.
Tianjin has high rates of MV and MMR-1 coverage, with lower levels for MMR-2. Most children who completed the series did so on-time. Maintaining high coverage and timely administration of MV and MMR-1 and increasing coverage of MMR-2 are necessary for China to attain the goal of national measles elimination.
PMCID: PMC4355170  PMID: 25259932
Measles; China; Vaccine Coverage
6.  Uniting adolescent neuroimaging and treatment research: Recommendations in pursuit of improved integration 
Many clinicians who provide mental health treatment find developmental neuroscience discoveries to be exciting. However, the utility of these findings often seem far removed from everyday clinical care. Thus, the goal of this article is to offer a bridge to connect the fields of applied adolescent treatment and developmental neuroscience investigation. An overview of the relevance of developmental neuroscience in adolescent direct practice and a rationale for how and why this integration could benefit adolescent treatment outcomes is provided. Finally, a series of practical suggestions is generated for enhancing collaborative, interdisciplinary work that ultimately advances treatment response for this important clinical population.
PMCID: PMC4767630  PMID: 26748378
Clinical; Adolescents; Developmental neuroscience
7.  Group motivational interviewing for adolescents: Change talk and alcohol and marijuana outcomes 
Little is known about what may distinguish effective and ineffective group interventions. Group motivational interviewing (MI) is a promising intervention for adolescent alcohol and other drug (AOD) use; however, the mechanisms of change for group MI are unknown. One potential mechanism is change talk, which is client speech arguing for change. The present study describes the group process in adolescent group MI and effects of group-level change talk on individual alcohol and marijuana outcomes.
We analyzed 129 group session audio recordings from a randomized clinical trial of adolescent group MI. Sequential coding was performed using the Motivational Interviewing Skill Code (MISC) and the CASAA Application for Coding Treatment Interactions (CACTI) software application. Outcomes included past-month intentions, frequency, and consequences of alcohol and marijuana use, motivation to change, and positive expectancies.
Sequential analysis indicated that facilitator open-ended questions and reflections of change talk (CT) increased group CT. Group CT was then followed by more CT. Multilevel models accounting for rolling group enrollment revealed group CT was associated with decreased alcohol intentions, alcohol use and heavy drinking three months later; group sustain talk was associated with decreased motivation to change, increased intentions to use marijuana, and increased positive alcohol and marijuana expectancies.
Facilitator speech and peer responses each had effects on change and sustain talk in the group setting, which was then associated with individual changes. Selective reflection of CT in adolescent group MI is suggested as a strategy to manage group dynamics and increase behavioral change.
PMCID: PMC4324015  PMID: 25365779
adolescents; substance use; intervention; group motivational interviewing; change talk; alcohol and marijuana outcomes
8.  Concentration-independent MRI of pH with a dendrimer-based pH-responsive nanoprobe 
The measurement of extracellular pH (pHe) has significant clinical value for pathological diagnoses and for monitoring the effects of pH-altering therapies. One of the major problems of measuring pHe with a relaxation-based MRI contrast agent is that the longitudinal relaxivity depends on both pH and the concentration of the agent, requiring the use of a second pH-unresponsive agent to measure the concentration. Here we tested the feasibility of measuring pH with a relaxation-based dendritic MRI contrast agent in a concentration-independent manner at clinically relevant field strengths. The transverse and longitudinal relaxation times in solutions of the contrast agent (GdDOTA-4AmP)44-G5, a G5–PAMAM dendrimer-based MRI contrast agent in water, were measured at 3 T and 7 T magnetic field strengths as a function of pH. At 3 T, longitudinal relaxivity (r1) increased from 7.91 to 9.65 mM−1 s−1 (on a per Gd3+ basis) on changing pH from 8.84 to 6.35. At 7 T, r1 relaxivity showed pH response, albeit at lower mean values; transverse relaxivity (r2) remained independent of pH and magnetic field strengths. The longitudinal relaxivity of (GdDOTA-4AmP)44-G5 exhibited a strong and reversible pH dependence. The ratio of relaxation rates R2/R1 also showed a linear relationship in a pH-responsive manner, and this pH response was independent of the absolute concentration of (GdDOTA-4AmP)44-G5 agent. Importantly, the nanoprobe (GdDOTA-4AmP)44-G5 shows pH response in the range commonly found in the microenvironment of solid tumors.
PMCID: PMC4713357  PMID: 26173742
responsive agent; noninvasive pH measurement; magnetic resonance imaging; dendritic agent
9.  Behavioral Weight Loss for the Management of Menopausal Hot Flashes: A Pilot Study 
Menopause (New York, N.Y.)  2015;22(1):59-65.
Although adiposity has been considered protective against hot flashes, newer data suggest positive relations between flashes and adiposity. No studies have been specifically designed to test whether weight loss reduces hot flashes. This pilot study aimed to evaluate the feasibility, acceptability, and initial efficacy of behavioral weight loss to reduce hot flashes.
Forty overweight/obese women with hot flashes (≥4/day) were randomized to a behavioral weight loss intervention or to wait list control. Hot flashes were assessed pre- and post-intervention via physiologic monitor, diary, and questionnaire. Comparisons of changes in hot flashes and anthropometrics between conditions were tested via Wilcoxon tests.
Study retention (83%) and intervention satisfaction (93.8%) were high. Most women (74.1%) reported that hot flash reduction was a main motivator to lose weight. Women randomized to the weight loss intervention lost more weight (-8.86 kg) than did women randomized to control (+0.23 kg, p<.0001). Women randomized to weight loss also showed greater reductions in questionnaire-reported hot flashes (2-week hot flashes: −63.0) than did women in the control (−28.0, p=.03), a difference not demonstrated in other hot flash measures. Reductions in weight and hot flashes were significantly correlated (e.g., r=.47, p=.006).
This pilot study showed a behavioral weight loss program to be feasible, acceptable, and effective in producing weight loss among overweight/obese women with hot flashes. Findings indicate the importance of a larger study designed to test behavioral weight loss for hot flash reduction. Hot flash management could motivate women to engage in this health-promoting behavior.
PMCID: PMC4270932  PMID: 24977456
Hot flashes; hot flushes; vasomotor symptoms; weight loss; weight; obesity
10.  Electronic Monitoring of Medication Adherence in Early Maintenance Phase Treatment for Pediatric Leukemia and Lymphoma: Identifying Patterns of Nonadherence 
Objective To describe patterns of treatment adherence to early maintenance phase therapy for acute lymphoblastic leukemia (ALL) and lymphoblastic lymphoma (LBL). Methods Using an objective observational method (electronic monitoring), adherence was examined for 139 patients aged 7–19 years diagnosed with ALL or LBL across 6 centers. Results The mean adherence percentage was 86.2%. Adherence rates declined over the 1-month of follow-up to 83%. 3 linear trajectories of 6-mercaptopurine adherence were identified: (1) exemplary adherence (n = 99): Averaging nearly 100%; (2) deteriorating (n = 23): Adherence decreased from 100 to 60%; and (3) chronically poor adherence (n = 9): Averaging 40%. Conclusions Adherence promotion interventions might be tailored to subgroups of patients who demonstrated problematic patterns of treatment adherence that could place them at risk for relapse. This research demonstrates the importance of using objective real-time measures of medication adherence for measuring and documenting adherence patterns.
PMCID: PMC4288299  PMID: 24365698
adherence; cancer and oncology; research design and methods; statistical applications
11.  Soil Functional Zone Management: A Vehicle for Enhancing Production and Soil Ecosystem Services in Row-Crop Agroecosystems 
There is increasing global demand for food, bioenergy feedstocks and a wide variety of bio-based products. In response, agriculture has advanced production, but is increasingly depleting soil regulating and supporting ecosystem services. New production systems have emerged, such as no-tillage, that can enhance soil services but may limit yields. Moving forward, agricultural systems must reduce trade-offs between production and soil services. Soil functional zone management (SFZM) is a novel strategy for developing sustainable production systems that attempts to integrate the benefits of conventional, intensive agriculture, and no-tillage. SFZM creates distinct functional zones within crop row and inter-row spaces. By incorporating decimeter-scale spatial and temporal heterogeneity, SFZM attempts to foster greater soil biodiversity and integrate complementary soil processes at the sub-field level. Such integration maximizes soil services by creating zones of ‘active turnover’, optimized for crop growth and yield (provisioning services); and adjacent zones of ‘soil building’, that promote soil structure development, carbon storage, and moisture regulation (regulating and supporting services). These zones allow SFZM to secure existing agricultural productivity while avoiding or minimizing trade-offs with soil ecosystem services. Moreover, the specific properties of SFZM may enable sustainable increases in provisioning services via temporal intensification (expanding the portion of the year during which harvestable crops are grown). We present a conceptual model of ‘virtuous cycles’, illustrating how increases in crop yields within SFZM systems could create self-reinforcing feedback processes with desirable effects, including mitigation of trade-offs between yield maximization and soil ecosystem services. Through the creation of functionally distinct but interacting zones, SFZM may provide a vehicle for optimizing the delivery of multiple goods and services in agricultural systems, allowing sustainable temporal intensification while protecting and enhancing soil functioning.
PMCID: PMC4743437  PMID: 26904043
crop yield; ecosystem services; precision tillage; soil biodiversity; soil management; temporal intensification; trade-offs; zonal tillage
12.  Transposable element detection from whole genome sequence data 
Mobile DNA  2015;6:24.
The number of software tools available for detecting transposable element insertions from whole genome sequence data has been increasing steadily throughout the last ~5 years. Some of these methods have unique features suiting them for particular use cases, but in general they follow one or more of a common set of approaches. Here, detection and filtering approaches are reviewed in the light of transposable element biology and the current state of whole genome sequencing. We demonstrate that the current state-of-the-art methods still do not produce highly concordant results and provide resources to assist future development in transposable element detection methods.
Electronic supplementary material
The online version of this article (doi:10.1186/s13100-015-0055-3) contains supplementary material, which is available to authorized users.
PMCID: PMC4696183  PMID: 26719777
Methods; Sequencing; Bioinformatics
13.  Vibrational Excitation of Both Products of the Reaction of CN Radicals with Acetone in Solution 
The Journal of Physical Chemistry. a  2015;119(50):12090-12101.
Transient electronic and vibrational absorption spectroscopy unravel the mechanisms and dynamics of bimolecular reactions of CN radicals with acetone in deuterated chloroform solutions. The CN radicals are produced by ultrafast ultraviolet photolysis of dissolved ICN. Two reactive forms of CN radicals are distinguished by their electronic absorption bands: “free” (uncomplexed) CN radicals, and “solvated” CN radicals that are complexed with solvent molecules. The lifetimes of the free CN radicals are limited to a few picoseconds following their photolytic production because of geminate recombination to ICN and INC, complexation with CDCl3 molecules, and reaction with acetone. The acetone reaction occurs with a rate coefficient of (8.0 ± 0.5) × 1010 M–1 s–1 and transient vibrational spectra in the C=N and C=O stretching regions reveal that both the nascent HCN and 2-oxopropyl (CH3C(O)CH2) radical products are vibrationally excited. The rate coefficient for the reaction of solvated CN with acetone is 40 times slower than for free CN, with a rate coefficient of (2.0 ± 0.9) × 109 M–1 s–1 obtained from the rise in the HCN product v1(C=N stretch) IR absorption band. Evidence is also presented for CN complexes with acetone that are more strongly bound than the CN–CDCl3 complexes because of CN interactions with the carbonyl group. The rates of reactions of these more strongly associated radicals are slower still.
PMCID: PMC4685429  PMID: 26192334
14.  Measurement of Rat Brain Tumor Kinetics Using an Intravascular MR Contrast Agent and DCE-MRI Nested Model Selection 
Using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in a rat glioma model, and nested model selection (NMS), to compare estimates of the pharmacokinetic parameters vp, Ktrans, and ve for two different contrast agents (CAs)—gadofosveset, which reversibly binds to human serum albumin, and gadopentetate dimeglumine, which does not.
Materials and Methods
DCE-MRI studies were performed on nine Fisher 344 rats inoculated intracerebrally with 9L gliosarcoma cells using both gadofosveset and gadopentetate. The parameters vp, Ktrans, and ve were estimated using NMS.
Ktrans estimates using gadofosveset, compared to gadopentetate, differed in their means (gadofosveset 0.025 ± 0.008 min−1 vs. gadopentetate 0.046 ± 0.011 min−1; P = 0.0039). This difference notwithstanding, the intraclass correlation coefficient (ICC) for the two estimates of Ktrans showed nearly perfect linear dependence (ICC = 0.8479 by Pearson’s r). Other estimates, ve (gadofosveset 22.7 ± 4.7% vs. gadopentetate 23.6 ± 5.6%; P = 0.4258) and vp (gadofosveset 1.5 ± 0.5% vs. gadopentetate 1.6 ± 0.4%; P = 0.25), were not different in their means between the two CAs, and there was almost perfect agreement for ve (ICC = 0.8798) and substantial agreement for vp (ICC = 0.7981) between the two CAs.
Estimates of Ktrans were statistically different using gadofosveset and gadopentetate, whereas ve and vp were similar with two CAs. NMS produced robust estimates of pharmacokinetic parameters using DCE-MRI that show promise as important measures of tumor physiology and microenvironment.
PMCID: PMC4686270  PMID: 24421265
gadofosveset; gadopentetate; DCE-MRI; contrast agent
15.  Personality Change due to Traumatic Brain Injury in Children and Adolescents: Neurocognitive Correlates 
Personality Change due to traumatic brain injury (PC) in children is an important psychiatric complication of injury and is a form of severe affective dysregulation. The aim of the study was to examine neurocognitive correlates of PC. The sample included children (n=177) aged 5-14 years with traumatic brain injury from consecutive admissions to 5 trauma centers were followed prospectively at baseline and 6 months with semi-structured psychiatric interviews. Injury severity, socioeconomic status, and neurocognitive function (measures of attention, processing speed, verbal memory, IQ, verbal working memory, executive function, naming/reading, expressive language, motor speed, and motor inhibition) were assessed with standardized instruments. Unremitted PC was present in 26/141 (18%) participants assessed at 6 months post-injury. Attention, processing speed, verbal memory, IQ, and executive function, were significantly associated (p < .05) with PC even after socioeconomic status, injury severity, and pre-injury attention-deficit/hyperactivity disorder were controlled. These findings are a first step in characterizing concomitant cognitive impairments associated with PC. The results have implications beyond brain injury to potentially elucidate the neurocognitive symptom complex associated with mood instability regardless of etiology.
PMCID: PMC4618043  PMID: 26185905
Traumatic brain injury; children and adolescents; cognition; personality change
16.  Brain-Based Origins of Change Language: A Beginning 
Addictive behaviors  2014;39(12):1904-1910.
Motivational interviewing (MI) is a promising treatment for heavy drinking. Client change talk (CT), a critical component of MI, has been associated with differential brain activation. The goal of this study was to begin to deconstruct how and why CT may affect the brain. Specifically, we sought to determine whether simply repeating statements in favor of change would cause differential brain activation, or whether client statements must be spontaneously generated within a therapeutic milieu in order to influence brain activation. We therefore examined blood oxygenation level dependent (BOLD) response following two types of client language (CT; and sustain talk, ST) across two conditions: (1) Self-Generated: CT and ST were elicited during an MI session vs. (2) Experimenter-Selected: a pre-established list of CT and ST was provided to the individual in the absence of an MI session. Across both conditions, participants’ CT and ST were visually and aurally presented during fMRI. We enrolled 39 recent binge drinkers (41% male; M age = 19.9; n = 18 in Self-Generated group; n = 21 in Experimenter-Selected group). We found that both types of client language (CT and ST) elicited greater BOLD activation in the Self-Generated vs. the Experimenter-Selected group in the left inferior frontal gyrus/anterior insula and superior temporal gyri (p ≤ 0.001). These findings indicate that the nature of client language matters. It appears that it is not just the words themselves, but the origin (naturally generated within a therapeutic session) that influences brain-based effects.
PMCID: PMC4240227  PMID: 25150658
alcohol; motivational interviewing; fMRI; client language
18.  How Well Do Computer-Generated Faces Tap Face Expertise? 
PLoS ONE  2015;10(11):e0141353.
The use of computer-generated (CG) stimuli in face processing research is proliferating due to the ease with which faces can be generated, standardised and manipulated. However there has been surprisingly little research into whether CG faces are processed in the same way as photographs of real faces. The present study assessed how well CG faces tap face identity expertise by investigating whether two indicators of face expertise are reduced for CG faces when compared to face photographs. These indicators were accuracy for identification of own-race faces and the other-race effect (ORE)–the well-established finding that own-race faces are recognised more accurately than other-race faces. In Experiment 1 Caucasian and Asian participants completed a recognition memory task for own- and other-race real and CG faces. Overall accuracy for own-race faces was dramatically reduced for CG compared to real faces and the ORE was significantly and substantially attenuated for CG faces. Experiment 2 investigated perceptual discrimination for own- and other-race real and CG faces with Caucasian and Asian participants. Here again, accuracy for own-race faces was significantly reduced for CG compared to real faces. However the ORE was not affected by format. Together these results signal that CG faces of the type tested here do not fully tap face expertise. Technological advancement may, in the future, produce CG faces that are equivalent to real photographs. Until then caution is advised when interpreting results obtained using CG faces.
PMCID: PMC4633121  PMID: 26535910
19.  ToF-SIMS imaging of lipids and lipid related compounds in Drosophila brain 
Surface and interface analysis : SIA  2014;46(Suppl 1):123-126.
Drosophila melanogaster (fruit fly) has a relatively simple nervous system but possesses high order brain functions similar to humans. Therefore, it has been used as a common model system in biological studies, particularly drug addiction. Here, the spatial distribution of biomolecules in the brain of the fly was studied using time-of flight secondary ion mass spectrometry (ToF-SIMS). Fly brains were analyzed frozen to prevent molecular redistribution prior to analysis. Different molecules were found to distribute differently in the tissue, particularly the eye pigments, diacylglycerides, and phospholipids, and this is expected to be driven by their biological functions in the brain. Correlations in the localization of these molecules were also observed using principal components analysis of image data, and this was used to identify peaks for further analysis. Furthermore, consecutive analyses following 10 keV Ar2500+ sputtering showed that different biomolecules respond differently to Ar2500+ sputtering. Significant changes in signal intensities between consecutive analyses were observed for high mass molecules including lipids.
PMCID: PMC4408320  PMID: 25918451
SIMS; imaging mass spectrometry; Drosophila; lipids
20.  Analysis of liposome model systems by time-of-flight secondary ion mass spectrometry 
Surface and interface analysis : SIA  2014;46(Suppl 1):74-78.
Time-of-flight secondary ion mass spectrometry (ToF-SIMS) is an important technique for studying chemical composition of micrometer scale objects due to its high spatial resolution imaging capabilities and chemical specificity. In this work we focus on the application of ToF-SIMS to gain insight into the chemistry of micrometer size liposomes as a potential model for neurotransmitter vesicles. Two models of giant liposomes were analyzed: histamine and aqueous two phase system (ATPS)-containing liposomes. Characterization of the internal structure of single fixed liposomes was done both with the Bi3+ and C60+ ion sources. The depth profiling capability of ToF-SIMS was used to investigate the liposome interior.
PMCID: PMC4408321  PMID: 25918450
liposome; aqueous two phase system; histamine; ToF-SIMS; depth profile analysis; imaging
21.  Moderated mediation analysis: An illustration using the association of gender with delinquency and mental health 
Journal of criminal psychology  2015;5(2):99-123.
When researchers find an association between two variables, it is useful to evaluate the role of other constructs in this association. While assessing these mediation effects, it is important to determine if results are equal for different groups. It is possible that the strength of a mediation effect may differ for males and females, for example – such an effect is known as moderated mediation.
Participants were 2532 adolescents from diverse ethnic/racial backgrounds and equally distributed across gender. The goal of this study was to investigate parental respect as a potential mediator of the relationship between gender and delinquency and mental health, and to determine whether observed mediation is moderated by gender.
Parental respect mediated the association between gender and both delinquency and mental health. Specifically, parental respect was a protective factor against delinquency and mental health problems for both females and males.
Practical implications
Demonstrated the process of estimating models in Lavaan, using two approaches (i.e. single group regression and multiple group regression model), and including covariates in both models.
PMCID: PMC4616155  PMID: 26500722
structural equation modelling; mediation; moderation; delinquency; gender; mental health; delinquency
22.  White matter and reading deficits after pediatric traumatic brain injury: A diffusion tensor imaging study 
NeuroImage : Clinical  2015;9:668-677.
Pediatric traumatic brain injury often results in significant long-term deficits in mastery of reading ability. This study aimed to identify white matter pathways that, when damaged, predicted reading deficits in children. Based on the dual-route model of word reading, we predicted that integrity of the inferior fronto-occipital fasciculus would be related to performance in sight word identification while integrity of the superior longitudinal fasciculus would be related to performance in phonemic decoding. Reading fluency and comprehension were hypothesized to relate to the superior longitudinal fasciculus, inferior fronto-occipital fasciculus, and cingulum bundle. The connectivity of white matter pathways was used to predict reading deficits in children aged 6 to 16 years with traumatic brain injury (n = 29) and those with orthopedic injury (n = 27) using tract-based spatial statistics. Results showed that children with traumatic brain injury and reduced microstructural integrity of the superior longitudinal fasciculus demonstrated reduced word-reading ability on sight word and phonemic decoding tasks. Additionally, children with traumatic brain injury and microstructural changes involving the cingulum bundle demonstrated reduced reading fluency. Results support the association of a dorsal pathway via the superior longitudinal fasciculus with both sight word reading and phonemic decoding. No association was identified between the inferior fronto-occipital fasciculus and sight word reading or phonemic decoding. Reading fluency was associated with the integrity of the cingulum bundle. These findings support dissociable pathways predicting word reading and fluency using Diffusion Tensor Imaging and provide additional information for developing models of acquired reading deficits by specifying areas of brain damage which may predict reading deficits following recovery from the acute phase of TBI.
•We apply models of white matter and reading ability to pediatric brain trauma.•We report dissociable effects for integrity of specific white matter pathways and specific reading skills following injury.•We report a relationship between the cingulum bundle and reading ability.•The implications of these findings are discussed in terms of brain-based reading models as they relate to brain injury.
PMCID: PMC4660156  PMID: 26740920
Reading; Diffusion Tensor Imaging; Traumatic brain injury; Pediatric
23.  Examining Racial/Ethnic Disparities in the Association between Adolescent Sleep and Alcohol or Marijuana Use 
Sleep health  2015;1(2):104-108.
The current study examines the association between self-reported measures of trouble sleeping, total sleep time (TST), and bedtimes and odds of past month alcohol and marijuana (AM) use in a racially/ethnically diverse sample of adolescents.
Web-based cross-sectional survey.
Los Angeles (LA) County, California.
The sample is comprised of 2539 youth representing four distinct racial/ethnic categories (Non-Hispanic White, Hispanic, Asian, and “Other”; mean age= 15.54; 54.23% female) from Los Angeles.
The survey assessed TST and bedtimes (weekdays and weekends), trouble sleeping, and past month AM use, as well as relevant covariates (sociodemographics and mental health symptoms).
Although there were significant racial/ethnic differences in the prevalence of sleep problems and AM use, the associations between sleep problems and AM use were consistent across racial/ethnic groups. Specifically, shorter TST, later bedtimes, and trouble sleeping, were each associated with significantly higher odds of past month alcohol use, whereas later bedtimes and shorter TST were also associated with increased odds of past month marijuana use, even after adjusting for other known risk factors.
Sleep problems are associated with increased AM use in teens, even after controlling for sociodemographics and mental health symptoms. Further longitudinal research on sleep and AM use is critical to identify novel prevention and intervention efforts to reduce disparities in the relationship between sleep and AM use.
PMCID: PMC4591872  PMID: 26436131
Adolescents; alcohol; marijuana; substance use; ethnic differences; disparities
24.  Combining Percutaneous Pedicular and Extrapedicular Access for Tumor Ablation in a Thoracic Vertebral Body 
Interventional Neuroradiology  null;20(5):603-608.
We present a percutaneous modified technique to access large thoracic vertebral body lytic lesions, to increase the volume of tumor accessible to ablation, prior to cement augmentation.
Tumor ablation and cavity creation-assisted percutaneous vertebroplasty was considered a palliative measure for structural stabilization in plasmocytoma involvement of the entire T8 vertebral body. Given the extent of osteolysis bilateral combined transpedicular and extrapedicular access to the vertebral body was undertaken to maximize the volume of cavity creation within the tumor.
The combined transpedicular and extrapedicular access was feasible, uncomplicated, and successful in reaching all the quadrants of the anterior two thirds of the vertebral body. Slow, fluoroscopically monitored injection of high-viscosity cement resulted in a successful, desired cement distribution into the anterior two thirds of the vertebral body, spanning superior to inferior endplates, providing structural stability, in the absence of venous or epidural leakage.
The technical modification described in this case yielded positive results while overcoming some of the limitations of the existing coblation device. This approach may offer an option for cement augmentation of extensive vertebral body lytic lesions, at increased risk for tumor displacement and extra-vertebral cement leakage.
PMCID: PMC4243230  PMID: 25363263
vertebroplasty; coblation; tumor ablation; spine tumor; plasmocytoma; osteolytic lesion
25.  T Lymphocyte Inhibition by Tumor-Infiltrating Dendritic Cells Involves Ectonucleotidase CD39 but Not Arginase-1 
BioMed Research International  2015;2015:891236.
T lymphocytes activated by dendritic cells (DC) which present tumor antigens play a key role in the antitumor immune response. However, in patients suffering from active cancer, DC are not efficient at initiating and supporting immune responses as they participate to T lymphocyte inhibition. DC in the tumor environment are functionally defective and exhibit a characteristic of immature phenotype, different to that of DC present in nonpathological conditions. The mechanistic bases underlying DC dysfunction in cancer responsible for the modulation of T-cell responses and tumor immune escape are still being investigated. Using two different mouse tumor models, we showed that tumor-infiltrating DC (TIDC) are constitutively immunosuppressive, exhibit a semimature phenotype, and impair responder T lymphocyte proliferation and activation by a mechanism involving CD39 ectoenzyme.
PMCID: PMC4605267  PMID: 26491691

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