rudyvdbrink/CitationDatabase huggingface dataset:
Small-Fiber Neuropathy Is Associated With Corneal Nerve and Dendritic Cell Alterations: An In Vivo Confocal Microscopy Study.
Cornea, 2015

In patients with small-fiber neuropathy (SFN), noninvasive diagnostic tests that allow accurate monitoring of disease progression are urgently needed. The aim of this study was to assess corneal trigeminal small sensory nerves and immune cells by in vivo corneal confocal microscopy (CCM) in SFN.
Perceptual modality norms for 1,121 Italian words: A comparison with concreteness and imageability scores and an analysis of their impact in word processing tasks.
Behavior research methods, 2020

Normative measures of verbal material are fundamental in psycholinguistic and cognitive research for the control of confounding in experimental procedures and for achieving a better comprehension of our conceptual system. Traditionally, normative studies have focused on classical psycholinguistic variables, such as concreteness and imageability. Recent works have shifted researchers' focus to perceptual strength, in which items are rated separately for each of the five senses. We present a resource that includes perceptual norms for 1,121 Italian words extracted from the Italian version of ANEW. Norms were collected from 57 native speakers. For each word, the participants provided perceptual-strength ratings for each of the five perceptual modalities. The perceptual norms performance in predicting human behavior was tested in two novel experiments, a lexical decision task and a naming task. Concreteness, imageability, and different composite variables representing perceptual-strength scores were considered as competing predictors in a series of linear regressions, evaluating the goodness of fit of each model. For both tasks, the model with imageability as the only predictor was found to be the best-fitting model according to the Akaike information criterion, whereas the model with the separately considered five modalities better described data according to the explained variance. These results differ from the ones previously reported for English, in which maximum perceptual strength emerged as the best predictor of behavior. We investigated this discrepancy by comparing Italian and English data for the same set of translated items, thus confirming a genuine cross-linguistic effect. We thus confirmed that perceptual experience influences linguistic processing, even though evaluations from different languages are needed to generalize this claim.
The Contribution of the Corpus Callosum to Language Lateralization.
The Journal of neuroscience : the official journal of the Society for Neuroscience, 2016

The development of hemispheric lateralization for language is poorly understood. In one hypothesis, early asymmetric gene expression assigns language to the left hemisphere. In an alternate view, language is represented a priori in both hemispheres and lateralization emerges via cross-hemispheric communication through the corpus callosum. To address this second hypothesis, we capitalized on the high temporal and spatial resolution of magnetoencephalographic imaging to measure cortical activity during language processing, speech preparation, and speech execution in 25 participants with agenesis of the corpus callosum (AgCC) and 21 matched neurotypical individuals. In contrast to strongly lateralized left hemisphere activations for language in neurotypical controls, participants with complete or partial AgCC exhibited bilateral hemispheric activations in both auditory or visually driven language tasks, with complete AgCC participants showing significantly more right hemisphere activations than controls or than individuals with partial AgCC. In AgCC individuals, language laterality positively correlated with verbal IQ. These findings suggest that the corpus callosum helps to drive language lateralization.
Neurobiological studies of fatigue.
Progress in neurobiology, 2012

Fatigue is a symptom associated with many disorders, is especially common in women and in older adults, and can have a huge negative influence on quality of life. Although most past research on fatigue uses human subjects instead of animal models, the use of appropriate animal models has recently begun to advance our understanding of the neurobiology of fatigue. In this review, results from animal models using immunological, developmental, or physical approaches to study fatigue are described and compared. Common across these animal models is that fatigue arises when a stimulus induces activation of microglia and/or increased cytokines and chemokines in the brain. Neurobiological studies implicate structures in the ascending arousal system, sleep executive control areas, and areas important in reward. In addition, the suprachiasmatic nucleus clearly plays an important role in homeostatic regulation of the neural network mediating fatigue. This nucleus responds to cytokines, shows decreased amplitude firing rate output in models of fatigue, and responds to exercise, one of our few treatments for fatigue. This is a young field but very important as the symptom of fatigue is common across many disorders and we do not have effective treatments.
Proximodistal segregation of nonspatial information in CA3: preferential recruitment of a proximal CA3-distal CA1 network in nonspatial recognition memory.
The Journal of neuroscience : the official journal of the Society for Neuroscience, 2013

A prevailing view in memory research is that CA3 principally supports spatial processes. However, few studies have investigated the contribution of CA3 to nonspatial memory function. Interestingly, the proximal part of CA3 (close to the dentate gyrus) predominantly projects to distal CA1 (away from the dentate gyrus), which preferentially processes nonspatial information. Moreover, the cytoarchitecture and connectivity patterns in the proximal and distal parts of CA3 strongly differ, suggesting a functional segregation in this area. Here, we tested whether CA3 is recruited during nonspatial recognition memory, and whether nonspatial information is differentially represented along the proximodistal axis of CA3. Furthermore, we investigated whether the pattern of activation within CA3 would mirror that of CA1. We used a high-resolution imaging technique specifically designed to analyze brain activity in distant areas that is based on the detection of the expression of the immediate-early gene Arc, used as a marker of neuronal activation. We showed that proximal CA3 is strongly recruited during a nonspatial delayed nonmatching-to-sample recognition memory task in rats, while distal CA3 is not. In addition, distal CA1 was more activated than proximal CA1 in the same task. These findings suggest a functional segregation of CA3 that mirrors that of CA1, and potentially indicate the existence of a proximal CA3-distal CA1 hippocampal subnetwork that would preferentially process nonspatial information during recognition memory.
The First Histological Analysis of the Tissues Lining the Fossa Navicularis: Insights to its Etiology.
Cureus, 2017

The fossa navicularis (FN) is an anatomical variant on the ventral surface of the basilar part of the occipital bone that, to date, has only been investigated in bone specimens. We aim to clarify the structure of the fossa navicularis by gross anatomical, radiological, and histological methods. The FN was found in the occipital bone of the Caucasian male cadaver. There was no bony or histological continuity between the FN and posterior cranial fossa. The histological analysis found that the overlying tissue was composed of loose connective tissue with a mixture of collagen and elastic fibers and a vascular matrix including arteries, veins, and capillaries. There was no evidence of lymphoid, glandular, or notochordal tissues. As no previous studies have performed histological analysis of the FN, this report adds to our knowledge of tissues that are involved in its formation.
Pronounced Hyperactivity, Cognitive Dysfunctions, and BDNF Dysregulation in Dopamine Transporter Knock-out Rats.
The Journal of neuroscience : the official journal of the Society for Neuroscience, 2018

Dopamine (DA) controls many vital physiological functions and is critically involved in several neuropsychiatric disorders such as schizophrenia and attention deficit hyperactivity disorder. The major function of the plasma membrane dopamine transporter (DAT) is the rapid uptake of released DA into presynaptic nerve terminals leading to control of both the extracellular levels of DA and the intracellular stores of DA. Here, we present a newly developed strain of rats in which the gene encoding DAT knockout Rats (DAT-KO) has been disrupted by using zinc finger nuclease technology. Male and female DAT-KO rats develop normally but weigh less than heterozygote and wild-type rats and demonstrate pronounced spontaneous locomotor hyperactivity. While striatal extracellular DA lifetime and concentrations are significantly increased, the total tissue content of DA is markedly decreased demonstrating the key role of DAT in the control of DA neurotransmission. Hyperactivity of DAT-KO rats can be counteracted by amphetamine, methylphenidate, the partial Trace Amine-Associated Receptor 1 (TAAR1) agonist RO5203648 ((S)-4-(3,4-Dichloro-phenyl)-4,5-dihydro-oxazol-2-ylamine) and haloperidol. DAT-KO rats also demonstrate a deficit in working memory and sensorimotor gating tests, less propensity to develop obsessive behaviors and show strong dysregulation in frontostriatal BDNF function. DAT-KO rats could provide a novel translational model for human diseases involving aberrant DA function and/or mutations affecting DAT or related regulatory mechanisms.
Scale for evaluation of movement disorders in the first three years of life.
Pediatric neurology, 2009

Most rating scales to assess movement disorders in children were mainly designed for adult patients, and are limited to a single type of disorder. A new scale for developmental age, the Movement Disorder-Childhood Rating Scale, was recently designed and validated for children and adolescents aged 4-18 years. We introduce a new version of this scale, the Movement Disorder-Childhood Rating Scale 0-3, suitable for application in children aged <4 years. The scale was tested for reliability and consistency in 40 children (aged 0.3-3.6 years) with different types of movement disorders. The results indicate high interrater agreement on each item, and a high degree of internal consistency on several proposed items. The scale can be used to assess and monitor young children with movement disorders during specific treatments.
Integrin expression is altered after acute and chronic cocaine.
Neuroscience letters, 2009

Cocaine addiction is associated with an increase in actin cycling and alterations in dendritic spines in the nucleus accumbens. Both actin polymerization and spine morphology are regulated in part by beta-(beta) integrins. Mice were administered acute or daily injections of cocaine or saline for 7 days. After 3 weeks of withdrawal, the level of beta-integrins in the postsynaptic density enriched subfraction from nucleus accumbens tissue was quantified by immunoblotting at 0, 30 or 120min following an a cocaine challenge injection. After chronic treatment and withdrawal the basal level of beta1-integrin was increased while beta3-integrin was unaltered. However, following a cocaine challenge in chronic cocaine, but not saline-treated animals, beta3-integrin was transiently up-regulated while beta1-integrin was transiently downregulated. These data demonstrate a bidirectional regulation of beta-integrins by chronic cocaine treatment that may contribute to cocaine-induced changes in actin cycling and dendrite morphology.
Psychosine accumulates in membrane microdomains in the brain of krabbe patients, disrupting the raft architecture.
The Journal of neuroscience : the official journal of the Society for Neuroscience, 2009

Lipid rafts (LRs) are membrane realms characterized by high concentrations of cholesterol and sphingolipids. Often, they are portrayed as scaffolds on which many different signaling molecules can assemble their cascades. The idea of rafts as scaffolds is garnering significant attention as the consequences of LR disruption have been shown to be manifest in multiple signaling pathways. In this study, LRs in the brain of the twitcher (TWI) mouse, a bona-fide model for infant variants of human globoid cell leukodystrophy or Krabbe disease, were investigated. This mouse has deficient activity of GALC (beta-galactosylceramidase) that leads to a progressive accumulation of some galactosyl-sphingolipids in the brain. We hypothesized that the accumulation of psychosine (galactosyl-sphingosine) in the TWI CNS may result in the disruption of rafts in different cell populations such as neurons and oligodendrocytes, both cellular targets during disease. In this communication, we demonstrate that psychosine specifically accumulates in LRs in the TWI brain and sciatic nerve and in samples from brains of human Krabbe patients. It is also shown that this accumulation is accompanied by an increase in cholesterol in these domains and changes in the distribution of the LR markers flotillin-2 and caveolin-1. Finally, we show evidence that this phenomenon may provide a mechanism by which psychosine can exert its known inhibitory effect on protein kinase C. This study provides a previously undescribed biophysical aspect for the mechanism of pathogenesis in Krabbe disease.
Ring models of binocular rivalry and fusion.
Journal of computational neuroscience, 2020

When similar visual stimuli are presented binocularly to both eyes, one perceives a fused single image. However, when the two stimuli are distinct, one does not perceive a single image; instead, one perceives binocular rivalry. That is, one perceives one of the stimulated patterns for a few seconds, then the other for few seconds, and so on - with random transitions between the two percepts. Most theoretical studies focus on rivalry, with few considering the coexistence of fusion and rivalry. Here we develop three distinct computational neuronal network models which capture binocular rivalry with realistic stochastic properties, fusion, and the hysteretic transition between. Each is a conductance-based point neuron model, which is multi-layer with two ocular dominance columns (L & R) and with an idealized "ring" architecture where the orientation preference of each neuron labels its location on a ring. In each model, the primary mechanism initiating binocular rivalry is cross-column inhibition, with firing rate adaptation governing the temporal properties of the transitions between percepts. Under stimulation by similar visual patterns, each of three models uses its own mechanism to overcome cross-column inhibition, and thus to prevent rivalry and allow the fusion of similar images: The first model uses cross-column feedforward inhibition from the opposite eye to "shut off" the cross-column feedback inhibition; the second model "turns on" a second layer of monocular neurons as a parallel pathway to the binocular neurons, rivaling out of phase with the first layer, and together these two pathways represent fusion; and the third model uses cross-column excitation to overcome the cross-column inhibition and enable fusion. Thus, each of the idealized ring models depends upon a different mechanism for fusion that might emerge as an underlying mechanism present in real visual cortex.
Role of multiple microRNAs in the sexually dimorphic expression of Cyp2b9 in mouse liver.
Drug metabolism and disposition: the biological fate of chemicals, 2013

Mouse cytochrome P450 2b9 (Cyp2b9) is a testosterone 16α-hydroxylase enzyme showing female-specific expression in many inbred mouse strains, including C57BL/6J. Previous studies have recognized that some sex-dependently secreted endogenous modulating factors were involved in the sexually dimorphic expression of Cyp2b9 through transcriptional regulation. In this study, we found evidence that some microRNAs contributed to the sexually biased expression of Cyp2b9 via post-transcriptional regulation. Cyp2b9 was upregulated in livers of hepatocyte-specific Dicer1 knockout mice at 3 weeks. The age-dependent downregulation of Cyp2b9 in the livers of male mice was diminished when Dicer1 was specifically knocked out in hepatocytes. When these data were combined with bioinformatics analysis and microRNA profiles of male and female mice, we found that 18 microRNAs were associated with the sexually dimorphic expression of Cyp2b9, which showed higher expression levels in male C57BL/6J mice when compared with females. Luciferase assays revealed that approximate half of these microRNAs repressed luciferase activity in a reporter system containing the 3'-untranslated region (3'-UTR) of Cyp2b9, and also inhibited Cyp2b9 protein expression. MicroRNA seed region mutation or mutations in putative binding sites of the microRNAs in Cyp2b9 3'-UTR led to the loss of the suppression of luciferase activity. There was also a negative correlation between the levels of these microRNAs and Cyp2b9. Our results suggested that multiple microRNAs participated in the regulation of Cyp2b9 expression, and that the lower expression levels of these microRNAs potentially contributed to the female-specific expression of Cyp2b9 in the livers of C57BL/6J mice.
Timekeeping in the hindbrain: a multi-oscillatory circadian centre in the mouse dorsal vagal complex.
Communications biology, 2020

Metabolic and cardiovascular processes controlled by the hindbrain exhibit 24 h rhythms, but the extent to which the hindbrain possesses endogenous circadian timekeeping is unresolved. Here we provide compelling evidence that genetic, neuronal, and vascular activities of the brainstem's dorsal vagal complex are subject to intrinsic circadian control with a crucial role for the connection between its components in regulating their rhythmic properties. Robust 24 h variation in clock gene expression in vivo and neuronal firing ex vivo were observed in the area postrema (AP) and nucleus of the solitary tract (NTS), together with enhanced nocturnal responsiveness to metabolic cues. Unexpectedly, we also find functional and molecular evidence for increased penetration of blood borne molecules into the NTS at night. Our findings reveal that the hindbrain houses a local network complex of neuronal and non-neuronal autonomous circadian oscillators, with clear implications for understanding local temporal control of physiology in the brainstem.
Individual differences in amygdala-medial prefrontal anatomy link negative affect, impaired social functioning, and polygenic depression risk.
The Journal of neuroscience : the official journal of the Society for Neuroscience, 2012

Individual differences in affective and social processes may arise from variability in amygdala-medial prefrontal (mPFC) circuitry and related genetic heterogeneity. To explore this possibility in humans, we examined the structural correlates of trait negative affect in a sample of 1050 healthy young adults with no history of psychiatric illness. Analyses revealed that heightened negative affect was associated with increased amygdala volume and reduced thickness in a left mPFC region encompassing the subgenual and rostral anterior cingulate cortex. The most extreme individuals displayed an inverse correlation between amygdala volume and mPFC thickness, suggesting that imbalance between these structures is linked to negative affect in the general population. Subgroups of participants were further evaluated on social (n = 206) and emotional (n = 533) functions. Individuals with decreased mPFC thickness exhibited the poorest social cognition and were least able to correctly identify facial emotion. Given prior links between disrupted amygdala-mPFC circuitry and the presence of major depressive disorder (MDD), we explored whether the individual differences in anatomy observed here in healthy young adults were associated with polygenic risk for MDD (n = 438) using risk scores derived from a large genome-wide association analysis (n = 18,759). Analyses revealed associations between increasing polygenic burden for MDD and reduced cortical thickness in the left mPFC. These collective findings suggest that, within the healthy population, there is significant variability in amygdala-mPFC circuitry that is associated with poor functioning across affective and social domains. Individual differences in this circuitry may arise, in part, from common genetic variability that contributes to risk for MDD.
An MRI study of white matter tract integrity in regular cannabis users: effects of cannabis use and age.
Psychopharmacology, 2016

Conflicting evidence exists on the effects of cannabis use on brain white matter integrity. The extant literature has exclusively focused on younger cannabis users, with no studies sampling older cannabis users.
Sequence alteration in the enhancer contributes to the heterochronic Sox9 expression in marsupial cranial neural crest.
Developmental biology, 2019

Neonates of marsupial mammals are altricial at birth, because their gestation period is relatively short compared to placental mammals. Yet, as they need to travel to the teat from the birth canal, and suckle on the mother's milk, forelimbs and jaws develop significantly early. Previous studies in opossum (Monodelphis domestica), an experimental marsupial model, have revealed that cranial neural crest cells are generated significantly early compared to those in placental mammals, such as mouse, leading to an early development of jaw primordia. We have previously found that Sox9, an important neural crest-specifier gene, is expressed in the future cranial neural crest of the opossum embryonic ectoderm significantly earlier than that in mouse or quail embryos. As Sox9 is essential for neural crest formation in various vertebrates, it seems likely that the heterochronic expression of Sox9 is critical for the early cranial neural crest formation in the marsupial embryos. In this study, we show a marsupial-specific sequence in the Sox9 neural crest enhancer E3. We also reveal that the mouse E3 enhancer is activated in the cranial neural crest cells of quail embryos, that the E3 enhancer with marsupial-specific sequence is activated earlier in the Pax7-expressing neural border prior to the onset of endogenous Sox9 expression, and that a misexpression of cMyb, which is also a transcriptional activator of Pax7, in the neural border can ectopically activate the "marsupialized" enhancer. Thus, we suggest that the modification of the E3 enhancer sequence in the marsupial ancestor would have promoted the early expression of Sox9 in the neural border, facilitating the early formation of the cranial neural crest cells and the subsequent heterochronic development of the jaw primordia.
Bilirubin enhances the activity of ASIC channels to exacerbate neurotoxicity in neonatal hyperbilirubinemia in mice.
Science translational medicine, 2020

Neonatal hyperbilirubinemia is a common clinical condition that can lead to brain encephalopathy, particularly when concurrent with acidosis due to infection, ischemia, and hypoxia. The prevailing view is that acidosis increases the permeability of the blood-brain barrier to bilirubin and exacerbates its neurotoxicity. In this study, we found that the concentration of the cell death marker, lactate dehydrogenase (LDH) in cerebrospinal fluid (CSF), is elevated in infants with both hyperbilirubinemia and acidosis and showed stronger correlation with the severity of acidosis rather than increased bilirubin concentration. In mouse neonatal neurons, bilirubin exhibits limited toxicity but robustly potentiates the activity of acid-sensing ion channels (ASICs), resulting in increases in intracellular Ca