59 research outputs found
The first record of the Sargocentron genus from the Maltese Islands (Central Mediterranean) - who will unravel the current conundrum?
The squirrelfish genus, Sargocentron, is reported for the first time from Maltese coastal waters within the Central Mediterranean. The record
is based on two individuals caught at two different coastal locations in the Maltese Islands within the space of a few days of each other,
through the same fishing technique (trammel nets). In view of the impossibility to collect meristic, morphometric and molecular data from
the recorded individuals, and due to the close similarity between a number of Sargocentron congeners, the exact taxonomic identity of the
captured individuals could not be conclusively confirmed, although the livery on the two caught individuals resulted to be consistent with
that of S. rubrum and S. hastatum.peer-reviewe
A biophysical model of endocannabinoid-mediated short term depression in hippocampal inhibition
Memories are believed to be represented in the synaptic pathways of vastly interconnected networks of neurons. The
plasticity of synapses, that is, their strengthening and weakening depending on neuronal activity, is believed to be the basis
of learning and establishing memories. An increasing number of studies indicate that endocannabinoids have a widespread
action on brain function through modulation of synapâtic transmission and plasticity. Recent experimental studies have
characterised the role of endocannabinoids in mediating both short- and long-term synaptic plasticity in various brain
regions including the hippocampus, a brain region strongly associated with cognitive functions, such as learning and
memory. Here, we present a biophysically plausible model of cannabinoid retrograde signalling at the synaptic level and
investigate how this signalling mediates depolarisation induced suppression of inhibition (DSI), a prominent form of shortterm
synaptic depression in inhibitory transmission in hippocampus. The model successfully captures many of the key
characteristics of DSI in the hippocampus, as observed experimentally, with a minimal yet sufficient mathematical
description of the major signalling molecules and cascades involved. More specifically, this model serves as a framework to
test hypotheses on the factors determining the variability of DSI and investigate under which conditions it can be evoked.
The model reveals the frequency and duration bands in which the post-synaptic cell can be sufficiently stimulated to elicit
DSI. Moreover, the model provides key insights on how the state of the inhibitory cell modulates DSI according to its firing
rate and relative timing to the post-synaptic activation. Thus, it provides concrete suggestions to further investigate
experimentally how DSI modulates and is modulated by neuronal activity in the brain. Importantly, this model serves as a
stepping stone for future deciphering of the role of endocannabinoids in synaptic transmission as a feedback mechanism
both at synaptic and network level
Zoledronate in the prevention of Paget's (ZiPP): Protocol for a randomised trial of genetic testing and targeted zoledronic acid therapy to prevent SQSTM1-mediated Paget's disease of bone
Differences in Brain Function and Changes with Intervention in Children with Poor Spelling and Reading Abilities
Previous fMRI studies in English-speaking samples suggested that specific interventions may alter brain function in language-relevant networks in children with reading and spelling difficulties, but this research strongly focused on reading impaired individuals. Only few studies so far investigated characteristics of brain activation associated with poor spelling ability and whether a specific spelling intervention may also be associated with distinct changes in brain activity patterns. We here investigated such effects of a morpheme-based spelling intervention on brain function in 20 children with comparatively poor spelling and reading abilities using repeated fMRI. Relative to 10 matched controls, children with comparatively poor spelling and reading abilities showed increased activation in frontal medial and right hemispheric regions and decreased activation in left occipito-temporal regions prior to the intervention, during processing of a lexical decision task. After five weeks of intervention, spelling and reading comprehension significantly improved in the training group, along with increased activation in the left temporal, parahippocampal and hippocampal regions. Conversely, the waiting group showed increases in right posterior regions. Our findings could indicate an increased left temporal activation associated with the recollection of the new learnt morpheme-based strategy related to successful training
Imaging of bronchial pathology in antibody deficiency: Data from the European Chest CT Group
Studies of chest computed tomography (CT) in patients with primary antibody deficiency syndromes (ADS) suggest a broad range of bronchial pathology. However, there are as yet no multicentre studies to assess the variety of bronchial pathology in this patient group. One of the underlying reasons is the lack of a consensus methodology, a prerequisite to jointly document chest CT findings. We aimed to establish an international platform for the evaluation of bronchial pathology as assessed by chest CT and to describe the range of bronchial pathologies in patients with antibody deficiency. Ffteen immunodeficiency centres from 9 countries evaluated chest CT scans of patients with ADS using a predefined list of potential findings including an extent score for bronchiectasis. Data of 282 patients with ADS were collected. Patients with common variable immunodeficiency disorders (CVID) comprised the largest subgroup (232 patients, 82.3%). Eighty percent of CVID patients had radiological evidence of bronchial pathology including bronchiectasis in 61%, bronchial wall thickening in 44% and mucus plugging in 29%. Bronchiectasis was detected in 44% of CVID patients aged less than 20 years. Cough was a better predictor for bronchiectasis than spirometry values. Delay of diagnosis as well as duration of disease correlated positively with presence of bronchiectasis. The use of consensus diagnostic criteria and a pre-defined list of bronchial pathologies allows for comparison of chest CT data in multicentre studies. Our data suggest a high prevalence of bronchial pathology in CVID due to late diagnosis or duration of disease
Neuroticism and extraversion in youth predict mental wellbeing and life satisfaction 40 years later
Neuroticism and Extraversion are linked with current wellbeing, but it is unclear whether these traits in youth predict wellbeing decades later. We applied structural equation modelling to data from 4583 people from the MRC National Survey of Health and Development. We examined the effects of Neuroticism and Extraversion at ages 16 and 26 years on mental wellbeing and life satisfaction at age 60-64 and explored the mediating roles of psychological and physical health. Extraversion had direct, positive effects on both measures of wellbeing. The impact of Neuroticism on both wellbeing and life satisfaction was largely indirect through susceptibility to psychological distress and physical health problems. Personality dispositions in youth have enduring influence on wellbeing assessed about forty years later
Multiple novel prostate cancer susceptibility signals identified by fine-mapping of known risk loci among Europeans
Genome-wide association studies (GWAS) have identified numerous common prostate cancer (PrCa) susceptibility loci. We have
fine-mapped 64 GWAS regions known at the conclusion of the iCOGS study using large-scale genotyping and imputation in
25 723 PrCa cases and 26 274 controls of European ancestry. We detected evidence for multiple independent signals at 16
regions, 12 of which contained additional newly identified significant associations. A single signal comprising a spectrum of
correlated variation was observed at 39 regions; 35 of which are now described by a novel more significantly associated lead SNP,
while the originally reported variant remained as the lead SNP only in 4 regions. We also confirmed two association signals in
Europeans that had been previously reported only in East-Asian GWAS. Based on statistical evidence and linkage disequilibrium
(LD) structure, we have curated and narrowed down the list of the most likely candidate causal variants for each region.
Functional annotation using data from ENCODE filtered for PrCa cell lines and eQTL analysis demonstrated significant
enrichment for overlap with bio-features within this set. By incorporating the novel risk variants identified here alongside the
refined data for existing association signals, we estimate that these loci now explain âŒ38.9% of the familial relative risk of PrCa,
an 8.9% improvement over the previously reported GWAS tag SNPs. This suggests that a significant fraction of the heritability of
PrCa may have been hidden during the discovery phase of GWAS, in particular due to the presence of multiple independent
signals within the same regio
Sex difference or hormonal difference in mental rotation? The influence of ovarian milieu
Multifractal analysis of information processing in hippocampal neural ensembles during working memory under Î9-tetrahydrocannabinol administration
BACKGROUND: Multifractal analysis quantifies the time-scale-invariant properties in data by describing the structure of variability over time. By applying this analysis to hippocampal interspike interval sequences recorded during performance of a working memory task, a measure of long-range temporal correlations and multifractal dynamics can reveal single neuron correlates of information processing. NEW METHOD: Wavelet leaders-based multifractal analysis (WLMA) was applied to hippocampal interspike intervals recorded during a working memory task. WLMA can be used to identify neurons likely to exhibit information processing relevant to operation of brainâcomputer interfaces and nonlinear neuronal models. RESULTS: Neurons involved in memory processing (âFunctional Cell Typesâ or FCTs) showed a greater degree of multifractal firing properties than neurons without task-relevant firing characteristics. In addition, previously unidentified FCTs were revealed because multifractal analysis suggested further functional classification. The cannabinoid-type 1 receptor partial agonist, tetrahydrocannabinol (THC), selectively reduced multifractal dynamics in FCT neurons compared to non-FCT neurons. COMPARISON WITH EXISTING METHODS: WLMA is an objective tool for quantifying the memory-correlated complexity represented by FCTs that reveals additional information compared to classification of FCTs using traditional z-scores to identify neuronal correlates of behavioral events. CONCLUSION: z-Score-based FCT classification provides limited information about the dynamical range of neuronal activity characterized by WLMA. Increased complexity, as measured with multifractal analysis, may be a marker of functional involvement in memory processing. The level of multifractal attributes can be used to differentially emphasize neural signals to improve computational models and algorithms underlying brainâcomputer interfaces
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