Visuo-auditory interactions in the primary visual cortex of the behaving monkey: Electrophysiological evidence

Background  

Visual, tactile and auditory information is processed from the periphery to the cortical level through separate channels that target primary sensory cortices, from which it is further distributed to functionally specialized areas. Multisensory integration is classically assigned to higher hierarchical cortical areas, but there is growing electrophysiological evidence in man and monkey of multimodal interactions in areas thought to be unimodal, interactions that can occur at very short latencies. Such fast timing of multisensory interactions rules out the possibility of an origin in the polymodal areas mediated through back projections, but is rather in favor of heteromodal connections such as the direct projections observed in the monkey, from auditory areas (including the primary auditory cortex AI) directly to the primary visual cortex V1. Based on the existence of such AI to V1 projections, we looked for modulation of neuronal visual responses in V1 by an auditory stimulus in the awake behaving monkey.     

Enhanced expressions of microvascular smooth muscle receptors after focal cerebral ischemia occur via the MAPK MEK/ERK pathway

Background  

MEK1/2 is a serine/threonine protein that phosphorylates extracellular signal-regulated kinase (ERK1/2). Cerebral ischemia results in enhanced expression of cerebrovascular contractile receptors in the middle cerebral artery (MCA) leading to the ischemic region. Here we explored the role of the MEK/ERK pathway in receptor expression following ischemic brain injury using the specific MEK1 inhibitor U0126.     

Prenatal stress and subsequent exposure to chronic mild stress influence dendritic spine density and morphology in the rat medial prefrontal cortex

Background  

Both prenatal stress (PS) and postnatal chronic mild stress (CMS) are associated with behavioral and mood disturbances in humans and rodents. The aim of this study was to reveal putative PS- and/or CMS-related changes in basal spine morphology and density of pyramidal neurons in the rat medial prefrontal cortex (mPFC).     

The role of shear stress in Blood-Brain Barrier endothelial physiology

Background  

One of the most important and often neglected physiological stimuli contributing to the differentiation of vascular endothelial cells (ECs) into a blood-brain barrier (BBB) phenotype is shear stress (SS). With the use of a well established humanized dynamic in vitro BBB model and cDNA microarrays, we have profiled the effect of SS in the induction/suppression of ECs genes and related functions.     

Peroxynitrite decomposition catalyst prevents apoptotic cell death in a human astrocytoma cell line incubated with supernatants of HIV-infected macrophages

Background  

Oxidative stress has shown to contribute in the mechanisms underlying apoptotic cell death occuring in AIDS-dementia complex. Here we investigated the role of peroxynitrite in apoptosis occurring in astroglial cells incubated with supernatants of HIV-infected human primary macrophages (M/M).     

MK801 attenuates secondary injury in a mouse experimental compression model of spinal cord trauma

Background  

Glutamergic excitotoxicity has been shown to play a deleterious role in the pathophysiology of spinal cord injury (SCI). The aim of this study was to investigate the neuroprotective effect of dizocilpine maleate, MK801 (2 mg/Kg, 30 min and 6 hours after injury) in a mice model of SCI. The spinal cord trauma was induced by the application of vascular clips to the dura via a four-level T5-T8 laminectomy.     

Neuromagnetic brain responses to words from semantic sub- and supercategories

Background  

We explored spatio-temporal patterns of cortical activity evoked by written words from super-ordinate and sub-ordinate semantic categories and hoped to find a differential cortical and/or temporal distribution of the brain response depending on the level of the categories. Twenty-three subjects saw 360 words belonging to six sub-ordinate categories (mammals, birds, fish, fruit, flowers, trees) within two super-ordinate categories (fauna, flora). Visually evoked magnetic fields were determined from whole-head (148-sensor) magnetoencephalography and analyzed in the source space (Minimum Norm Estimate).     

Usefulness of event-related potentials in the assessment of mild cognitive impairment

Background  

The aim of this study was to determine if changes in latencies and amplitudes of the major waves of Auditory Event-Related Potentials (AERP), correlate with memory status of patients with mild cognitive impairment (MCI) and conversion to Alzheimer's disease (AD).     

Dimerization of the transmembrane domain of amyloid precursor proteins and familial Alzheimer's disease mutants

Background  

Amyloid precursor protein (APP) is enzymatically cleaved by γ-secretase to form two peptide products, either Aβ40 or the more neurotoxic Aβ42. The Aβ42/40 ratio is increased in many cases of familial Alzheimer's disease (FAD). The transmembrane domain (TM) of APP contains the known dimerization motif GXXXA. We have investigated the dimerization of both wild type and FAD mutant APP transmembrane domains.     

Matrix metalloproteinase-7 facilitates immune access to the CNS in experimental autoimmune encephalomyelitis

Background  

Metalloproteinase inhibitors can protect mice against experimental autoimmune encephalomyelitis (EAE), an animal model for multiple sclerosis (MS). Matrix metalloproteinase-9 (MMP-9) has been implicated, but it is not clear if other MMPs are also involved, including matrilysin/MMP-7 – an enzyme capable of cleaving proteins that are essential for blood brain barrier integrity and immune suppression.     

Expression of Cre recombinase in dopaminoceptive neurons

Background  

Dopamine-activated signaling regulates locomotor and emotional responses and alterations in dopamine-signaling are responsible of several psychomotor disorders. In order to identify specific functions of these pathways, the Cre/loxP system has been used. Here, we describe the generation and the characterization of a transgenic mouse line expressing the Cre recombinase in dopaminoceptive neurons. To this purpose, we used as expression vector a 140 kb yeast artificial chromosome (YAC) containing the dopamine D1 receptor gene (Drd1a).     

Effect of neutrophil depletion on gelatinase expression,edema formation and hemorrhagic transformation after focal ischemic stroke

Background  

While gelatinase (MMP-2 and -9) activity is increased after focal ischemia/reperfusion injury in the brain, the relative contribution of neutrophils to the MMP activity and to the development of hemorrhagic transformation remains unknown.     

Stage effects of negative emotion on spatial and verbal working memory

Background  

The effects of negative emotion on different processing periods in spatial and verbal working memory (WM) and the possible brain mechanism of the interaction between negative emotion and WM were explored using a high-time resolution event-related potential (ERP) technique and time-locked delayed matching-to-sample task (DMST).     

One-pot synthesis of benzochromeno-pyrazole derivatives

Abstract  

One-pot synthesis of different benzochromeno-pyrazole derivatives has been reported via reaction of aldehydes, 3-methyl-1H-pyrazol-5(4H)-one and α-naphthol/β-naphthol in the presence of sulfamic acid.     

Focused ultrasound-mediated suppression of chemically-induced acute epileptic EEG activity

Background  

Epilepsy is a common neurological disorder, which is attributed to uncontrollable abnormal hyper-excitability of neurons. We investigated the feasibility of using low-intensity, pulsed radiation of focused ultrasound (FUS) to non-invasively suppress epileptic activity in an animal model (rat), which was induced by the intraperitonial injection of pentylenetetrazol (PTZ).     

Imbalanced pattern completion vs. separation in cognitive disease: network simulations of synaptic pathologies predict a personalized therapeutics strategy

Background  

Diverse Mouse genetic models of neurodevelopmental, neuropsychiatric, and neurodegenerative causes of impaired cognition exhibit at least four convergent points of synaptic malfunction: 1) Strength of long-term potentiation (LTP), 2) Strength of long-term depression (LTD), 3) Relative inhibition levels (Inhibition), and 4) Excitatory connectivity levels (Connectivity).     

Non-rapid eye movement sleep with low muscle tone as a marker of rapid eye movement sleep regulation

Background  

It was recently reported that epochs of non-REM sleep (NREMS) with low muscle tone represent a partial correlate of REM sleep (REMS). To further investigate this phenomenon, episodes of restricted night-time sleep (23:00 – 03.00h) and subsequent morning sleep (10:00 – 13:00h) were analysed.     

ADHD candidate gene (DRD4 exon III) affects inhibitory control in a healthy sample

Background  

Dopamine is believed to be a key neurotransmitter in the development of attention-deficit/hyperactivity disorder (ADHD). Several recent studies point to an association of the dopamine D4 receptor (DRD4) gene and this condition. More specifically, the 7 repeat variant of a variable number of tandem repeats (VNTR) polymorphism in exon III of this gene is suggested to bear a higher risk for ADHD. In the present study, we investigated the role of this polymorphism in the modulation of neurophysiological correlates of response inhibition (Go/Nogo task) in a healthy, high-functioning sample.     

Altered maternal profiles in corticotropin-releasing factor receptor 1 deficient mice

Background  

During lactation, the CNS is less responsive to the anxiogenic neuropeptide, corticotropin-releasing factor (CRF). Further, central injections of CRF inhibit maternal aggression and some maternal behaviors, suggesting decreased CRF neurotransmission during lactation supports maternal behaviors. In this study, we examined the maternal profile of mice missing the CRF receptor 1 (CRFR1). Offspring of knockout (CRFR1-/-) mice were heterozygote to offset possible deleterious effects of low maternal glucocorticoids on pup survival and all mice contained a mixed 50:50 inbred/outbred background to improve overall maternal profiles and fecundity.