Role of chiral-induced spin selectivity in the radical pair mechanism of avian magnetoreception.

In this paper, we investigate the effect of chiral-induced spin selectivity (CISS) on the radical pair mechanism of avian magnetoreception. We examine the impact of spin selectivity on the avian compass sensitivity. In this analysis, we also consider the dipolar and exchange interactions and observe their interplay with CISS.

Magnetic resonance imaging of blood-brain barrier permeability in ischemic stroke using diffusion-weighted arterial spin labeling in rats.

Diffusion-weighted arterial spin labeling magnetic resonance imaging has recently been proposed to quantify the rate of water exchange (K) across the blood-brain barrier in humans. This study aimed to evaluate the blood-brain barrier disruption in transient (60 min) ischemic stroke using K magnetic resonance imaging with cross-validation by dynamic contrast-enhanced magnetic resonance imaging and Evans blue histology in the same rats. The major findings were: (i) at 90 min after stroke (30 min after reperfusion), group K magnetic resonance imaging data showed no significant blood-brain barrier permeability changes, although a few animals showed slightly abnormal K.

Methylene blue and normobaric hyperoxia combination therapy in experimental ischemic stroke.

Introduction: Ischemic stroke is a global burden that contributes to the disability and mortality of millions of patients. This study aimed to evaluate the efficacy of combined MB (methylene blue) and NBO (normobaric hyperoxia) therapy in experimental ischemic stroke.

Methods: Rats with transient (60 min) MCAO (middle cerebral artery occlusion) were treated with: (1) air + vehicle (N = 8), (2) air + MB (N = 8), (3) NBO + vehicle (N = 7), and (4) NBO + MB (N = 9).

Effects of stroke severity and treatment duration in normobaric hyperoxia treatment of ischemic stroke.

In order to improve clinical trial design and translation of normobaric oxygen (NBO) treatment of ischemic stroke, NBO treatment parameters need to be better understood. This study investigated NBO treatment efficacy at two different stroke severities and two NBO treatment durations in rats. For the 60-min middle cerebral artery occlusion (MCAO), NBO treatment for 25 min and 150 min were studied.

Characterisation of genetic variation in ST8SIA2 and its interaction region in NCAM1 in patients with bipolar disorder.

Alpha-2,8-sialyltransferase 2 (ST8SIA2) is an enzyme responsible for the transfer of polysialic acid (PSA) to glycoproteins, principally the neuronal cell adhesion molecule (NCAM1), and is involved in neuronal plasticity. Variants within ST8SIA2 have previously shown association with bipolar disorder, schizophrenia and autism. In addition, altered PSA-NCAM expression in brains of patients with schizophrenia or bipolar disorder indicates a functional dysregulation of glycosylation in mental illness.

Quantitative cerebral blood flow measurements using MRI.

Magnetic resonance imaging can be utilized as a quantitative and noninvasive method to image cerebral blood flow. The two most common techniques used to detect cerebral blood flow are dynamic susceptibility contrast (DSC) perfusion MRI and arterial spin labeling perfusion MRI. Herein we describe the use of these two techniques to measure cerebral blood flow in rodents, including methods, analysis, and important considerations when utilizing these techniques.

FMRI of deep brain stimulation at the rat ventral posteromedial thalamus.

Background: Functional magnetic resonance imaging (fMRI) of deep brain stimulation (DBS) has potentials to reveal neuroanatomical connectivity of a specific brain region in vivo.

Objective: This study aimed to demonstrate frequency and amplitude tunings of the thalamocortical tract using DBS fMRI at the rat ventral posteromedial thalamus.

Methods: Blood oxygenation level dependent (BOLD) fMRI data were acquired in a total of twelve rats at a high-field 11.

Rethinking schizophrenia in the context of normal neurodevelopment.

The schizophrenia brain is differentiated from the normal brain by subtle changes, with significant overlap in measures between normal and disease states. For the past 25 years, schizophrenia has increasingly been considered a neurodevelopmental disorder. This frame of reference challenges biological researchers to consider how pathological changes identified in adult brain tissue can be accounted for by aberrant developmental processes occurring during fetal, childhood, or adolescent periods.

Selected rapporteur summaries from the XX World Congress of Psychiatric Genetics, Hamburg, Germany, October 14-18, 2012.

The XXth World Congress of Psychiatric Genetics (WCPG), sponsored by The International Society of Psychiatric Genetics (ISPG) took place in Hamburg, Germany on October 14-18, 2012. Approximately 600 participants gathered to discuss the latest findings in this rapidly advancing field. The following report was written by student travel awardees.

Identification of sialyltransferase 8B as a generalized susceptibility gene for psychotic and mood disorders on chromosome 15q25-26.

We previously identified a significant bipolar spectrum disorder linkage peak on 15q25-26 using 35 extended families with a broad clinical phenotype, including bipolar disorder (types I and II), recurrent unipolar depression and schizoaffective disorder. However, the specific gene(s) contributing to this signal had not been identified. By a fine mapping association study in an Australian case-control cohort (n = 385), we find that the sialyltransferase 8B (ST8SIA2) gene, coding for an enzyme that glycosylates proteins involved in neuronal plasticity which has previously shown association to both schizophrenia and autism, is associated with increased risk to bipolar spectrum disorder.

Assessing oxidative pathway genes as risk factors for bipolar disorder.

Objectives: There is a growing body of evidence implicating oxidative stress and the glutathione system in the pathogenesis of major psychiatric illnesses, including schizophrenia and bipolar disorder. Here we investigate whether genes involved in oxidative stress regulation are associated with increased risk for bipolar disorder.

Methods: Four candidate genes were selected a priori from two different steps in the oxidative stress pathway, specifically the synthesis of glutathione [catalytic subunit of glutamate cysteine ligase (GCLC) and regulatory subunit of glutamate cysteine ligase (GCLM)] and the removal of reactive oxygen species [superoxide dismutase 2 (SOD2) and glutathione peroxidase 3 (GPX3)].