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Functional linear regression model with randomly censored data: Predicting conversion time to Alzheimer's disease

Yang, Seong J.; Shin, Hyejin; Lee, Sang Han; Lee, Seokho
ISI:000539101800008
ISSN: 0167-9473
CID: 4525122

Profiles of infant communicative behavior

Margolis, Amy E; Lee, Sang Han; Peterson, Bradley S; Beebe, Beatrice
Prior studies of mother-infant interaction have generally used a variable-centered approach to associate face-to-face communication with psychosocial outcomes. Herein, we use a person-centered approach to identify clusters of infants who exhibit similar behavioral profiles during face-to-face communication with their mothers. Four infant communication channels were examined-gaze, facial affect, vocal affect, and head orientation-coded from videotape at a 1-s temporal resolution. We used k-means clustering to classify community infants (N = 132) into 10 groups, based on variation in the intercept and the autocorrelation function at the first time lag, representing respectively the overall level of behavior and the predictability of the infant's moment-by-moment behavioral stream, in each of the 4 communication channels. In this exploratory study, 10 clusters were identified, some with unusual levels or predictability of behavior in varying channels, and clusters associated differentially with risk outcomes (infant 4-month temperament and 12-month attachment). Distinct forms of affective dysregulation were identified: sustained negative vocal affect associated with degree of disorganization; random vocal affect associated with attachment resistance; random facial affect and vocal affect, irrespective of positive/negative valence, associated with infant difficult temperament. Clustering multiple channels of infant communication generated unique behavioral profiles and predicted 4- and 12-month outcomes, suggesting that these clusters may indeed represent natural types of infant communicative behavior, not easily observed with the naked eye, that may be useful behavioral markers of clinical risk. (PsycINFO Database Record (c) 2019 APA, all rights reserved).
PMID: 31169399
ISSN: 1939-0599
CID: 3918022

Long-term effects of maternal choline supplementation on CA1 pyramidal neuron gene expression in the Ts65Dn mouse model of Down syndrome and Alzheimer's disease

Alldred, Melissa J; Chao, Helen M; Lee, Sang Han; Beilin, Judah; Powers, Brian E; Petkova, Eva; Strupp, Barbara J; Ginsberg, Stephen D
Choline is critical for normative function of 3 major pathways in the brain, including acetylcholine biosynthesis, being a key mediator of epigenetic regulation, and serving as the primary substrate for the phosphatidylethanolamine N-methyltransferase pathway. Sufficient intake of dietary choline is critical for proper brain function and neurodevelopment. This is especially important for brain development during the perinatal period. Current dietary recommendations for choline intake were undertaken without critical evaluation of maternal choline levels. As such, recommended levels may be insufficient for both mother and fetus. Herein, we examined the impact of perinatal maternal choline supplementation (MCS) in a mouse model of Down syndrome and Alzheimer's disease, the Ts65Dn mouse relative to normal disomic littermates, to examine the effects on gene expression within adult offspring at ∼6 and 11 mo of age. We found MCS produces significant changes in offspring gene expression levels that supersede age-related and genotypic gene expression changes. Alterations due to MCS impact every gene ontology category queried, including GABAergic neurotransmission, the endosomal-lysosomal pathway and autophagy, and neurotrophins, highlighting the importance of proper choline intake during the perinatal period, especially when the fetus is known to have a neurodevelopmental disorder such as trisomy.-Alldred, M. J., Chao, H. M., Lee, S. H., Beilin, J., Powers, B. E., Petkova, E., Strupp, B. J., Ginsberg, S. D. Long-term effects of maternal choline supplementation on CA1 pyramidal neuron gene expression in the Ts65Dn mouse model of Down syndrome and Alzheimer's disease.
PMID: 31180719
ISSN: 1530-6860
CID: 3929822

Family nurture intervention for preterm infants facilitates positive mother-infant face-to-face engagement at 4 months

Beebe, Beatrice; Myers, Michael M; Lee, Sang Han; Lange, Adrianne; Ewing, Julie; Rubinchik, Nataliya; Andrews, Howard; Austin, Judy; Hane, Amie; Margolis, Amy E; Hofer, Myron; Ludwig, Robert J; Welch, Martha G
Although preterm infants are at risk for social deficits, interventions to improve mother-infant interaction in the neonatal intensive care unit (NICU) are not part of standard care (SC). Study participants were a subset from a randomized controlled trial of a new intervention for premature infants, the Family Nurture Intervention (FNI), designed to help mothers and infants establish an emotional connection. At infants' 4 months corrected age, mother-infant face-to-face interaction was filmed and coded on a 1-s time base for mother touch, infant vocal affect, mother gaze, and infant gaze. Time-series models assessed self- and interactive contingency. Comparing FNI to SC dyads, FNI mothers showed more touch and calmer touch patterns, and FNI infants showed more angry-protest but less cry. In maternal touch self-contingency, FNI mothers were more likely to sustain positive touch and to repair moments of negative touch by transitioning to positive touch. In maternal touch interactive contingency, when infants looked at mothers, FNI mothers were likely to respond with more positive touch. In infant vocal affect self-contingency, FNI infants were more likely to sustain positive vocal affect and to transition from negative to positive vocal affect. In maternal gaze interactive contingency, following infants' looking at mother, FNI mothers of male infants were more likely to look at their sons. In maternal gaze self-contingency, following mothers' looking away, FNI mothers of male infants were more likely to look at their sons. Documentation of positive effects of the FNI for 4-month mother-infant face-to-face communication is useful clinically and has important implications for an improved developmental trajectory of these infants. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
PMID: 30284883
ISSN: 1939-0599
CID: 3352842

Fused Lasso Regression for Identifying Differential Correlations in Brain Connectome Graphs

Yu, Donghyeon; Lee, Sang Han; Lim, Johan; Xiao, Guanghua; Craddock, R Cameron; Biswal, Bharat B
In this paper, we propose a procedure to find differential edges between two graphs from high-dimensional data. We estimate two matrices of partial correlations and their differences by solving a penalized regression problem. We assume sparsity only on differences between two graphs, not graphs themselves. Thus, we impose an â„“ 2 penalty on partial correlations and an â„“ 1 penalty on their differences in the penalized regression problem. We apply the proposed procedure to finding differential functional connectivity between healthy individuals and Alzheimer's disease patients.
PMCID:8356776
PMID: 34386148
ISSN: 1932-1864
CID: 5068862

CA1 pyramidal neuron gene expression mosaics in the Ts65Dn murine model of Down syndrome and Alzheimer's disease following maternal choline supplementation (MCS)

Alldred, Melissa J; Chao, Helen M; Lee, Sang Han; Beilin, Judah; Powers, Brian E; Petkova, Eva; Strupp, Barbara J; Ginsberg, Stephen D
Although there are changes in gene expression and alterations in neuronal density and afferent inputs in the forebrain of trisomic mouse models of Down syndrome (DS) and Alzheimer's disease (AD), there is a lack of systematic assessments of gene expression and encoded proteins within individual vulnerable cell populations, precluding translational investigations at the molecular and cellular level. Further, no effective treatment exists to combat intellectual disability and basal forebrain cholinergic neurodegeneration seen in DS. To further our understanding of gene expression changes before and following cholinergic degeneration in a well-established mouse model of DS/AD, the Ts65Dn mouse, we assessed RNA expression levels from CA1 pyramidal neurons at two adult ages (∼6 months of age and ∼11 months of age) in both Ts65Dn and their normal disomic (2N) littermates. We further examined a viable therapeutic, maternal choline supplementation (MCS), which has been previously shown to lessen dysfunction in spatial cognition and attention, and have protective effects on the survival of basal forebrain cholinergic neurons (BFCNs) in the Ts65Dn mouse model. Results indicate that MCS normalized expression of several genes in key gene ontology categories, including synaptic plasticity, calcium signaling, and AD-associated neurodegeneration related to amyloid-beta peptide (Aβ) clearance. Specifically, normalized expression levels were found for endothelin converting enzyme-2 (Ece2), insulin degrading enzyme (Ide), Dyrk1a, and calcium/calmodulin-dependent protein kinase II (Camk2a), among other relevant genes. Single population expression profiling of vulnerable CA1 pyramidal neurons indicates that MCS is a viable therapeutic for long-term reprogramming of key transcripts involved in neuronal signaling that are dysregulated in the trisomic mouse brain which have translational potential for DS and AD.
PMCID:5874173
PMID: 29394516
ISSN: 1098-1063
CID: 2933942

Expression profiling suggests microglial impairment in HIV neuropathogenesis

Ginsberg, Stephen D; Alldred, Melissa J; Gunnam, Satya M; Schiroli, Consuelo; Lee, Sang Han; Morgello, Susan; Fischer, Tracy
OBJECTIVE:CD16+ /CD163+ macrophages (MΦ)s and microglia accumulate in the brains of patients with HIV encephalitis (HIVE), a neuropathological correlate of the most severe form of HIV-associated neurocognitive disorders (HAND), HIV-associated dementia (HIV-D). Recently, we found that some parenchymal microglia in brain of HIV+ subjects without encephalitis (HIV/noE) but with varying degrees of neurocognitive impairment express CD16 and CD163, even in the absence of detectable virus production. To further our understanding of microglial activation in HIV, we investigated expression of specific genes by profiling parenchymal microglia from archival brain tissue of patients with HIVE, HIV/noE, and HIV- controls. METHODS:Single-population microarray analyses were performed on ∼2,500 laser capture microdissected CD163+ , CD16+ or CD68+ MΦs/microglia per case, using terminal continuation (TC) RNA amplification and a custom-designed array platform. RESULTS:Several classes of microglial transcripts in HIVE and HIV/noE, were altered, relative to HIV- subjects, including factors related to cell stress, immune activation, and apoptosis. Additionally, several neurotrophic factors are reduced in HIV infection, suggesting an additional mechanism of neuropathogenesis. The majority of transcripts altered in HIVE displayed intermediate changes in HIV/noE. INTERPRETATION/CONCLUSIONS:Our results support the notion that microglia contribute to the maintenance of brain homeostasis and their potential loss of function in the context of chronic inflammation contributes to neuropathogenesis. Furthermore, they indicate the utility of profiling MΦs/microglia to increase our understanding of microglia function, as well as ascertain alterations in specific pathways, genes, and, ostensibly, encoded proteins that may be amenable to targeted treatment modalities in diseases affecting the brain.
PMCID:5822676
PMID: 29369399
ISSN: 1531-8249
CID: 2929212

What can the study of first impressions tell us about attitudinal ambivalence and paranoia in schizophrenia?

Tremeau, Fabien; Antonius, Daniel; Todorov, Alexander; Rebani, Yasmina; Ferrari, Kelsey; Lee, Sang Han; Calderone, Daniel; Nolan, Karen A; Butler, Pamela; Malaspina, Dolores; Javitt, Daniel C
Although social cognition deficits have been associated with schizophrenia, social trait judgments - or first impressions - have rarely been studied. These first impressions, formed immediately after looking at a person's face, have significant social consequences. Eighty-one individuals with schizophrenia or schizoaffective disorder and 62 control subjects rated 30 neutral faces on 10 positive or negative traits: attractive, mean, trustworthy, intelligent, dominant, fun, sociable, aggressive, emotionally stable and weird. Compared to controls, patients gave higher ratings for positive traits as well as for negative traits. Patients also demonstrated more ambivalence in their ratings. Patients who were exhibiting paranoid symptoms assigned higher intensity ratings for positive social traits than non-paranoid patients. Social trait ratings were negatively correlated with everyday problem solving skills in patients. Although patients appeared to form impressions of others in a manner similar to controls, they tended to assign higher scores for both positive and negative traits. This may help explain the social deficits observed in schizophrenia: first impressions of higher degree are harder to correct, and ambivalent attitudes may impair the motivation to interact with others. Consistent with research on paranoia and self-esteem, actively-paranoid patients' positive social traits judgments were of higher intensity than non-paranoid patients'.
PMID: 27086216
ISSN: 1872-7123
CID: 2079282

Brain-Wide Insulin Resistance, Tau Phosphorylation Changes, and Hippocampal Neprilysin and Amyloid-beta Alterations in a Monkey Model of Type 1 Diabetes

Morales-Corraliza, Jose; Wong, Harrison; Mazzella, Matthew J; Che, Shaoli; Lee, Sang Han; Petkova, Eva; Wagner, Janice D; Hemby, Scott E; Ginsberg, Stephen D; Mathews, Paul M
Epidemiological findings suggest that diabetic individuals are at a greater risk for developing Alzheimer's disease (AD). To examine the mechanisms by which diabetes mellitus (DM) may contribute to AD pathology in humans, we examined brain tissue from streptozotocin-treated type 1 diabetic adult male vervet monkeys receiving twice-daily exogenous insulin injections for 8-20 weeks. We found greater inhibitory phosphorylation of insulin receptor substrate 1 in each brain region examined of the diabetic monkeys when compared with controls, consistent with a pattern of brain insulin resistance that is similar to that reported in the human AD brain. Additionally, a widespread increase in phosphorylated tau was seen, including brain areas vulnerable in AD, as well as relatively spared structures, such as the cerebellum. An increase in active ERK1/2 was also detected, consistent with DM leading to changes in tau-kinase activity broadly within the brain. In contrast to these widespread changes, we found an increase in soluble amyloid-beta (Abeta) levels that was restricted to the temporal lobe, with the greatest increase seen in the hippocampus. Consistent with this localized Abeta increase, a hippocampus-restricted decrease in the protein and mRNA for the Abeta-degrading enzyme neprilysin (NEP) was found, whereas various Abeta-clearing and -degrading proteins were unchanged. Thus, we document multiple biochemical changes in the insulin-controlled DM monkey brain that can link DM with the risk of developing AD, including dysregulation of the insulin-signaling pathway, changes in tau phosphorylation, and a decrease in NEP expression in the hippocampus that is coupled with a localized increase in Abeta. SIGNIFICANCE STATEMENT: Given that diabetes mellitus (DM) appears to increase the risk of developing Alzheimer's disease (AD), understanding the mechanisms by which DM promotes AD is important. We report that DM in a nonhuman primate brain leads to changes in the levels or posttranslational processing of proteins central to AD pathobiology, including tau, amyloid-beta (Abeta), and the Abeta-degrading protease neprilysin. Additional evidence from this model suggests that alterations in brain insulin signaling occurred that are reminiscent of insulin signaling pathway changes seen in human AD. Thus, in anin vivomodel highly relevant to humans, we show multiple alterations in the brain resulting from DM that are mechanistically linked to AD risk.
PMCID:4829649
PMID: 27076423
ISSN: 1529-2401
CID: 2077582

Predicting progression from mild cognitive impairment to Alzheimer's disease using longitudinal callosal atrophy

Lee, Sang Han; Bachman, Alvin H; Yu, Donghyeon; Lim, Johan; Ardekani, Babak A
INTRODUCTION: We investigate whether longitudinal callosal atrophy could predict conversion from mild cognitive impairment (MCI) to Alzheimer's disease (AD). METHODS: Longitudinal (baseline + 1-year follow-up) MRI scans of 132 MCI subjects from the Alzheimer's Disease Neuroimaging Initiative were used. A total of 54 subjects did not convert to AD over an average (+/-SD) follow-up of 5.46 (+/-1.63) years, whereas 78 converted to AD with an average conversion time of 2.56 (+/-1.65) years. Annual change in the corpus callosum thickness profile was calculated from the baseline and 1-year follow-up MRI. A logistic regression model with fused lasso regularization for prediction was applied to the annual changes. RESULTS: We found a sex difference. The accuracy of prediction was 84% in females and 61% in males. The discriminating regions of corpus callosum differed between sexes. In females, the genu, rostrum, and posterior body had predictive power, whereas the genu and splenium were relevant in males. DISCUSSION: Annual callosal atrophy predicts MCI-to-AD conversion in females more accurately than in males.
PMCID:4879655
PMID: 27239537
ISSN: 2352-8729
CID: 2124742