Daniel Alicata

Structural Growth Trajectories and Rates of Change in the First 3 Months of Infant Brain Development

IMPORTANCE The very early postnatal period witnesses extraordinary rates of growth, but structural brain development in this period has largely not been explored longitudinally. Such assessment may be key in detecting and treating the earliest signs of neurodevelopmental disorders. OBJECTIVE To assess structural growth trajectories and rates of change in the whole brain and regions of interest in infants during the first 3 months after birth. DESIGN, SETTING, AND PARTICIPANTS Serial structural T1-weighted and/or T2-weighted magnetic resonance images were obtained for 211 time points from 87 healthy term-born or term-equivalent preterm-born infants, aged 2 to 90 days, between October 5, 2007, and June 12, 2013. MAIN OUTCOMES AND MEASURES We segmented whole-brain and multiple subcortical regions of interest using a novel application of Bayesian-based methods. We modeled growth and rate of growth trajectories nonparametrically and assessed left-right asymmetries and sexual dimorphisms. RESULTS Whole-brain volume at birth was approximately one-third of healthy elderly brain volume, and did not differ significantly between male and female infants (347 388 mm3 and 335 509 mm3, respectively, P = .12). The growth rate was approximately 1%/d, slowing to 0.4%/d by the end of the first 3 months, when the brain reached just more than half of elderly adult brain volume. Overall growth in the first 90 days was 64%. There was a significant age-by-sex effect leading to widening separation in brain sizes with age between male and female infants (with male infants growing faster than females by 200.4 mm3/d, SE = 67.2, P = .003). Longer gestation was associated with larger brain size (2215 mm3/d, SE = 284, P = 4×10-13). The expected brain size of an infant born one week earlier than average was 5% smaller than average; at 90 days it will not have caught up, being 2% smaller than average. The cerebellum grew at the highest rate, more than doubling in 90 days, and the hippocampus grew at the slowest rate, increasing by 47% in 90 days. There was left-right asymmetry in multiple regions of interest, particularly the lateral ventricles where the left was larger than the right by 462 mm3 on average (approximately 5% of lateral ventricular volume at 2 months). We calculated volume-by-age percentile plots for assessing individual development. CONCLUSIONS AND RELEVANCE Normative trajectories for early postnatal brain structural development can be determined from magnetic resonance imaging and could be used to improve the detection of deviant maturational patterns indicative of neurodevelopmental disorders.

Higher diffusion in striatum and lower fractional anisotropy in white matter of methamphetamine users

Methamphetamine (METH) users showed structural and chemical abnormalities on magnetic resonance (MRI) studies, particularly in the frontal and basal ganglia brain regions. Diffusion tensor imaging (DTI) may provide further insights regarding the microstructural changes in METH users. We investigated diffusion tensor measures in frontal white matter and basal ganglia of 30 adult METH users and 30 control subjects using a 3 T MR scanner. Compared with healthy control subjects, METH users showed lower fractional anisotropy (FA) in right frontal white matter, and higher apparent diffusion coefficient (ADC) in left caudate and bilateral putamen. Higher left putamen ADC was associated with earlier initiation of METH use, greater daily amounts, and a higher cumulative lifetime dose. Similarly, higher right putamen ADC was associated with greater daily amounts and a higher cumulative lifetime dose. The lower FA in the right frontal white matter suggests axonal injury in these METH users. The higher ADC in the basal ganglia suggests greater inflammation or less myelination in these brain regions of those with younger age of first METH use and greater METH usage.

Association between Psychiatric Symptoms and Craving in Methamphetamine Users

This study examined the differences in psychiatric symptoms between adult methamphetamine users (n = 46) and control subjects (n = 31), the relationship between psychiatric symptoms and the intensity of methamphetamine craving, and whether psychiatric symptoms were correlated to methamphetamine drug-usage variables (ie, length of abstinence, frequency, duration, and lifetime grams). We found that depressive symptoms on the Center for Epidemiology Studies-Depression (CES-D) and many other psychiatric symptoms on the Symptom Checklist-90 (SCL-90) significantly correlated with craving methamphetamine on the visual analog scale (VAS) for craving. Methamphetamine users had significantly more depressive symptoms (on CES-D) and psychotic symptoms (on SCL-90) compared to controls. There were no significant correlations between psychiatric symptoms and methamphetamine-usage variables. This study provides the first evidence to suggest that depressive symptoms (on CES-D) and psychiatric symptoms (on SCL-90) are strongly associated with the intensity of craving (on VAS) for the drug in methamphetamine users. However, the methamphetamine usage variables had no relationship with psychiatric symptoms. Therefore, methamphetamine users, regardless of their usage patterns, may benefit from treatment of their psychiatric symptoms in order to minimize craving and subsequent relapse to drug use.

Sustained‐release methylphenidate in a randomized trial of treatment of methamphetamine use disorder

BACKGROUND AND AIMS No effective pharmacotherapy for methamphetamine (MA) use disorder has yet been found. This study evaluated sustained-release methylphenidate (MPH-SR) compared with placebo (PLA) for treatment of MA use disorder in people also undergoing behavioral support and motivational incentives. DESIGN This was a randomized, double-blind, placebo-controlled design with MPH-SR or PLA provided for 10 weeks (active phase) followed by 4 weeks of single-blind PLA. Twice-weekly clinic visits, weekly group counseling (CBT) and motivational incentives (MI) for MA-negative urine drug screens (UDS) were included. SETTING Treatment sites were in Los Angeles, California (LA) and Honolulu, Hawaii (HH), USA. PARTICIPANTS A total of 110 MA-dependent (via DSM-IV) participants (LA = 90; HH = 20). MEASUREMENTS The primary outcome measure is self-reported days of MA use during the last 30 days of the active phase. Included in the current analyses are drug use (UDS and self-report), retention, craving, compliance (dosing, CBT, MI), adverse events and treatment satisfaction. FINDINGS No difference was found between treatment groups in self-reported days of MA use during the last 30 days of the active phase (P = 0.22). In planned secondary outcomes analyses, however, the MPH group had fewer self-reported MA use days from baseline through the active phase compared with the PLA group (P = 0.05). The MPH group also had lower craving scores and fewer marijuana-positive UDS than the PLA group in the last 30 days of the active phase. The two groups had similar retention, other drug use, adverse events and treatment satisfaction. CONCLUSIONS Methylphenidate may lead to a reduction in concurrent methamphetamine use when provided as treatment for patients undergoing behavioral support for moderate to severe methamphetamine use disorder, but this requires confirmation.

Probabilistic maps of the white matter tracts with known associated functions on the neonatal brain atlas: Application to evaluate longitudinal developmental trajectories in term-born and preterm-born infants

Diffusion tensor imaging (DTI) has been widely used to investigate the development of the neonatal and infant brain, and deviations related to various diseases or medical conditions like preterm birth. In this study, we created a probabilistic map of fiber pathways with known associated functions, on a published neonatal multimodal atlas. The pathways-of-interest include the superficial white matter (SWM) fibers just beneath the specific cytoarchitectonically defined cortical areas, which were difficult to evaluate with existing DTI analysis methods. The Jülich cytoarchitectonic atlas was applied to define cortical areas related to specific brain functions, and the Dynamic Programming (DP) method was applied to delineate the white matter pathways traversing through the SWM. Probabilistic maps were created for pathways related to motor, somatosensory, auditory, visual, and limbic functions, as well as major white matter tracts, such as the corpus callosum, the inferior fronto-occipital fasciculus, and the middle cerebellar peduncle, by delineating these structures in eleven healthy term-born neonates. In order to characterize maturation-related changes in diffusivity measures of these pathways, the probabilistic maps were then applied to DTIs of 49 healthy infants who were longitudinally scanned at three time-points, approximately five weeks apart. First, we investigated the normal developmental pattern based on 19 term-born infants. Next, we analyzed 30 preterm-born infants to identify developmental patterns related to preterm birth. Last, we investigated the difference in diffusion measures between these groups to evaluate the effects of preterm birth on the development of these functional pathways. Term-born and preterm-born infants both demonstrated a time-dependent decrease in diffusivity, indicating postnatal maturation in these pathways, with laterality seen in the corticospinal tract and the optic radiation. The comparison between term- and preterm-born infants indicated higher diffusivity in the preterm-born infants than in the term-born infants in three of these pathways: the body of the corpus callosum; the left inferior longitudinal fasciculus; and the pathway connecting the left primary/secondary visual cortices and the motion-sensitive area in the occipitotemporal visual cortex (V5/MT+). Probabilistic maps provided an opportunity to investigate developmental changes of each white matter pathway. Whether alterations in white matter pathways can predict functional outcomes will be further investigated in a follow-up study.

Age and sex effects levels of choline compounds in the anterior cingulate cortex of adolescent methamphetamine users

BACKGROUND Methamphetamine can be neurotoxic to the adult brain; however, many individuals first use methamphetamine during adolescence, and the drugs impact on this period of brain development is unknown. Therefore, we evaluated young methamphetamine users for possible abnormalities in brain metabolite concentrations. METHODS Anterior cingulate cortex (ACC), frontal white matter (FWM), basal ganglia, and thalamus were studied with localized proton magnetic resonance spectroscopy in 54 periadolescent (ages 13-23 years) methamphetamine users and 53 comparison subjects. The concentrations of major brain metabolites and their associations with age, sex and cognition were assessed. RESULTS FWM total-creatine correlated with age in methamphetamine-using males and comparison females, but not comparison males or methamphetamine-using females, leading to a drug by sex by age interaction (p=0.003) and ACC choline-containing compounds (CHO) correlated with age only in comparison males leading to a drug by sex by age interaction (p=0.03). Higher ACC CHO was associated with faster performance on the Stroop Interference task in the control males. Male methamphetamine users had slowest performance on the Stroop Interference task and did not show age-appropriate levels of ACC CHO. CONCLUSIONS The altered age-appropriate levels of ACC CHO and poorer executive function in male methamphetamine users suggest methamphetamine abuse may interfere with brain maturation. These periadolescents did not have the abnormal neuronal markers previously reported in adult methamphetamine users, suggesting that neuronal abnormalities may be the result of long-term use or interference in normal cortical maturation, emphasizing the need for early intervention for young methamphetamine users.

Sex-Specific Alterations of White Matter Developmental Trajectories in Infants With Prenatal Exposure to Methamphetamine and Tobacco

Importance Methamphetamine is a common illicit drug used worldwide. Methamphetamine and/or tobacco use by pregnant women remains prevalent. However, little is known about the effect of comorbid methamphetamine and tobacco use on human fetal brain development. Objective To investigate whether microstructural brain abnormalities reported in children with prenatal methamphetamine and/or tobacco exposure are present at birth before childhood environmental influences. Design, Setting, and Participants A prospective, longitudinal study was conducted between September 17, 2008, and February 28, 2015, at an ambulatory academic medical center. A total of 752 infant-mother dyads were screened and 139 of 195 qualified neonates were evaluated (36 methamphetamine/tobacco exposed, 32 tobacco exposed, and 71 unexposed controls). They were recruited consecutively from the community. Exposures Prenatal methamphetamine and/or tobacco exposure. Main Outcomes and Measures Quantitative neurologic examination and diffusion tensor imaging performed 1 to 3 times through age 4 months; diffusivities and fractional anisotropy (FA) assessed in 7 white matter tracts and 4 subcortical brain regions using an automated atlas-based method. Results Of the 139 infants evaluated, 72 were female (51.8%); the mean (SE) postmenstrual age at baseline was 41.5 (0.27) weeks. Methamphetamine/tobacco-exposed infants showed delayed developmental trajectories on active muscle tone (group × age, P < .001) and total neurologic scores (group × age, P = .01) that normalized by ages 3 to 4 months. Only methamphetamine/tobacco-exposed boys had lower FA (group × age, P = .02) and higher diffusivities in superior (SCR) and posterior corona radiatae (PCR) (group × age × sex, P = .002; group × age × sex, P = .01) at baseline that normalized by age 3 months. Only methamphetamine/tobacco- and tobacco-exposed girls showed persistently lower FA in anterior corona radiata (ACR) (group, P = .04; group × age × sex, P = .01). Tobacco-exposed infants showed persistently lower axial diffusion in the thalamus and internal capsule across groups (P = .02). Conclusions and Relevance Prenatal methamphetamine/tobacco exposure may lead to delays in motor development, with less coherent fibers and less myelination in SCR and PCR only in male infants, but these abnormalities may normalize by ages 3 to 4 months after cessation of stimulant exposure. In contrast, persistently less coherent ACR fibers were observed in methamphetamine/tobacco- and tobacco-exposed girls, possibly from increased dendritic branching or spine density due to epigenetic influences. Persistently lower diffusivity in the thalamus and internal capsule of all tobacco-exposed infants suggests aberrant axonal development. Collectively, prenatal methamphetamine and/or tobacco exposure may lead to delayed motor development and white matter maturation in sex- and regional-specific manners.

Delayed early developmental trajectories of white matter tracts of functional pathways in preterm-born infants: Longitudinal diffusion tensor imaging data.

Probabilistic maps of white matter pathways related to motor, somatosensory, auditory, visual, and limbic functions, and major white matter tracts (the corpus callosum, the inferior fronto-occipital fasciculus, and the middle cerebellar peduncle) were applied to evaluate the developmental trajectories of these tracts, using longitudinal diffusion tensor imaging (DTI) obtained in term-born and preterm-born healthy infants. Nineteen term-born and 30 preterm-born infants completed MR scans at three time points: Time-point 1, 41.6±2.7 postmenstrual weeks; Time-point 2, 46.0±2.9 postmenstrual weeks; and Time-point 3, 50.8±3.7 postmenstrual weeks. The DTI-derived scalar values (fractional anisotropy, eigenvalues, and radial diffusivity) of the three time points are available in this Data article.

Imaging peri-adolescent pruning of the frontal cortex and cognitive maturation

the redox status and the expression of Mrp1 in proliferating and differentiating NPC. NPC were obtained from E15 mouse brains, growing as neurospheres in the presence of EGF and bFGF. Differentiation was firstly induced by plating NPC onto poly-d-lysine-coated plates in the presence of low concentrations of bFGF. Cells were cultured in the absence of bFGF for 4, 8 and 18 DIV. Cell viability was determined by trypan blue, total glutathione (GSt) by an enzymatic assay, protein oxidation and lipid peroxidation by slot-blot analysis and Mrp1 by western blot, in NPC and differentiating cells. NPC differentiated in astrocytes and neurons, with the first representing 55% at 4 DIV and 64% at 18 DIV. Loss of cell viability increased ∼6-fold (p < 0.01) from proliferating NPC to 4, 8 and 18 DIV differentiating cells. Curiously, NPC showed a high level of intracellular GSt (∼3-fold, p < 0.05), as well as protein oxidation (∼1.6-fold, p < 0.01) and lipid peroxidation (∼2.5-fold, p < 0.01), as compared to the lower level obtained in differentiating cells. Moreover, our data evidenced that Mrp1 is highly expressed in NPC. Immature cells (4 DIV) presented the lowest levels of Mrp1 and during nerve cell maturation this protein slightly increased, although never reaching the expression levels of NPC (∼0.7-fold for 4 and 8 DIV, p < 0,05; 0.9-fold for 18 DIV; versus NPC). In conclusion, NPC proliferation is associated with increased levels of protein and lipid oxidation. Therefore, the higher concentrations of GSt and Mrp1 expression observed in NPC seem to constitute self-defense mechanisms against oxidative injury. Funded by FCT-PTDC/SAU-NEU/64385/2006 to D.B.

Gender differences in reasons for methamphetamine use in an ethnically diverse population in Hawaii

Abstract Objectives: This preliminary study examined methamphetamine (MA) use behaviors and motivators for MA use among 46 ethnically diverse participants from an university-affiliated community hospital and narcotics anonymous groups in Hawaii. Method: Data were collected among 46 participants using an anonymous survey. Results: Results showed that both women and men use MA primarily to get high and to get more energy. Women were more likely than men to use MA to cope with negative feelings and for increased energy. Men were more likely than women to use MA for sexual reasons and due to peer pressure. Conclusion: These results suggest that some women may be self-medicating with MA. Studying these behaviors may guide in developing future prevention and treatment strategies.