407 research outputs found
Genetic contributions to visuospatial cognition in Williams syndrome: insights from two contrasting partial deletion patients
Background
Williams syndrome (WS) is a rare neurodevelopmental disorder arising from a hemizygotic deletion of approximately 27 genes on chromosome 7, at locus 7q11.23. WS is characterised by an uneven cognitive profile, with serious deficits in visuospatial tasks in comparison to relatively proficient performance in some other cognitive domains such as language and face processing. Individuals with partial genetic deletions within the WS critical region (WSCR) have provided insights into the contribution of specific genes to this complex phenotype. However, the combinatorial effects of different genes remain elusive.
Methods
We report on visuospatial cognition in two individuals with contrasting partial deletions in the WSCR: one female (HR), aged 11 years 9 months, with haploinsufficiency for 24 of the WS genes (up to GTF2IRD1), and one male (JB), aged 14 years 2 months, with the three most telomeric genes within the WSCR deleted, or partially deleted.
Results
Our in-depth phenotyping of the visuospatial domain from table-top psychometric, and small- and large-scale experimental tasks reveal a profile in HR in line with typically developing controls, albeit with some atypical features. These data are contrasted with patient JB’s atypical profile of strengths and weaknesses across the visuospatial domain, as well as with more substantial visuospatial deficits in individuals with the full WS deletion.
Conclusions
Our findings point to the contribution of specific genes to spatial processing difficulties associated with WS, highlighting the multifaceted nature of spatial cognition and the divergent effects of genetic deletions within the WSCR on different components of visuospatial ability. The importance of general transcription factors at the telomeric end of the WSCR, and their combinatorial effects on the WS visuospatial phenotype are also discussed
The side effect profile of Clozapine in real world data of three large mental health hospitals
Objective:
Mining the data contained within Electronic Health Records (EHRs) can potentially generate
a greater understanding of medication effects in the real world, complementing what we
know from Randomised control trials (RCTs). We Propose a text mining approach to detect
adverse events and medication episodes from the clinical text to enhance our understanding
of adverse effects related to Clozapine, the most effective antipsychotic drug for the management of treatment-resistant schizophrenia, but underutilised due to concerns over its
side effects.
Material and methods:
We used data from de-identified EHRs of three mental health trusts in the UK (>50 million
documents, over 500,000 patients, 2835 of which were prescribed Clozapine). We explored
the prevalence of 33 adverse effects by age, gender, ethnicity, smoking status and admission type three months before and after the patients started Clozapine treatment. Where
possible, we compared the prevalence of adverse effects with those reported in the Side
Effects Resource (SIDER).
Results:
Sedation, fatigue, agitation, dizziness, hypersalivation, weight gain, tachycardia, headache,
constipation and confusion were amongst the highest recorded Clozapine adverse effect in
the three months following the start of treatment. Higher percentages of all adverse effects
were found in the first month of Clozapine therapy. Using a significance level of (p< 0.05)
our chi-square tests show a significant association between most of the ADRs and smoking
status and hospital admission, and some in gender, ethnicity and age groups in all trusts
hospitals. Later we combined the data from the three trusts hospitals to estimate the average effect of ADRs in each monthly interval. In gender and ethnicity, the results show significant association in 7 out of 33 ADRs, smoking status shows significant association in 21 out
of 33 ADRs and hospital admission shows the significant association in 30 out of 33 ADRs.
Conclusion:
A better understanding of how drugs work in the real world can complement clinical trials
Effect of trazodone on cognitive decline in people with dementia: Cohort study using UK routinely collected data
Objectives: Evidence in mouse models has found that the antidepressant trazodone may be protective against neurodegeneration. We therefore aimed to compare cognitive decline of people with dementia taking trazodone with those taking other antidepressants. // Methods: Three identical naturalistic cohort studies using UK clinical registers. We included all people with dementia assessed during 2008–16 who were recorded taking trazodone, citalopram or mirtazapine for at least 6 weeks. Linear mixed models examined age, time and sex-adjusted Mini-mental state examination (MMSE) change in people with all-cause dementia taking trazodone compared with those taking citalopram and mirtazapine. In secondary analyses, we examined those with non-vascular dementia; mild dementia; and adjusted results for neuropsychiatric symptoms. We combined results from the three study sites using random-effects meta-analysis. // Results: We included 2,199 people with dementia, including 406 taking trazodone, with mean 2.2 years follow-up. There was no difference in adjusted cognitive decline in people with all-cause or non-vascular dementia taking trazodone, citalopram or mirtazapine in any of the three study sites. When data from the three sites were combined in meta-analysis, we found greater mean MMSE decline in people with all-cause dementia taking trazodone compared to those taking citalopram (0·26 points per successive MMSE measurement, 95% CI 0·03–0·49; p = 0·03). Results in sensitivity analyses were consistent with primary analyses. // Conclusions: There was no evidence of cognitive benefit from trazodone compared to other antidepressants in people with dementia in three naturalistic cohort studies. Despite preclinical evidence, trazodone should not be advocated for cognition in dementia
The side effect profile of Clozapine in real world data of three large mental hospitals
Objective: Mining the data contained within Electronic Health Records (EHRs)
can potentially generate a greater understanding of medication effects in the
real world, complementing what we know from Randomised control trials (RCTs).
We Propose a text mining approach to detect adverse events and medication
episodes from the clinical text to enhance our understanding of adverse effects
related to Clozapine, the most effective antipsychotic drug for the management
of treatment-resistant schizophrenia, but underutilised due to concerns over
its side effects. Material and Methods: We used data from de-identified EHRs of
three mental health trusts in the UK (>50 million documents, over 500,000
patients, 2835 of which were prescribed Clozapine). We explored the prevalence
of 33 adverse effects by age, gender, ethnicity, smoking status and admission
type three months before and after the patients started Clozapine treatment. We
compared the prevalence of adverse effects with those reported in the Side
Effects Resource (SIDER) where possible. Results: Sedation, fatigue, agitation,
dizziness, hypersalivation, weight gain, tachycardia, headache, constipation
and confusion were amongst the highest recorded Clozapine adverse effect in the
three months following the start of treatment. Higher percentages of all
adverse effects were found in the first month of Clozapine therapy. Using a
significance level of (p< 0.05) out chi-square tests show a significant
association between most of the ADRs in smoking status and hospital admissions
and some in gender and age groups. Further, the data was combined from three
trusts, and chi-square tests were applied to estimate the average effect of
ADRs in each monthly interval. Conclusion: A better understanding of how the
drug works in the real world can complement clinical trials and precision
medicine
Evolutionary prisoner's dilemma game on a square lattice
A simplified prisoner's game is studied on a square lattice when the players
interacting with their neighbors can follow only two strategies: to cooperate
(C) or to defect (D) unconditionally. The players updated in a random sequence
have a chance to adopt one of the neighboring strategies with a probability
depending on the payoff difference. Using Monte Carlo simulations and dynamical
cluster techniques we study the density of cooperators in the stationary
state. This system exhibits a continuous transition between the two absorbing
state when varying the value of temptation to defect. In the limits
and 1 we have observed critical transitions belonging to the universality class
of directed percolation.Comment: 6 pages including 6 figure
GMRT 333 MHz observations of 6 nearby normal galaxies
We report Giant Meterwave Radio Telescope (GMRT) continuum observations of
six nearby normal galaxies at 333 MHz. The galaxies are observed with angular
resolutions better than ~20" (corresponding to a linear scale of about 0.4 - 1
kpc). These observations are sensitive to all the angular scales of interest,
since the resolution of the shortest baseline in GMRT is greater than the
angular size of the galaxies. Further, for five of these galaxies we show that
at 333 MHz, the mean thermal fraction is less than 5%. Using archival data at
about 1 GHz, we estimate the mean thermal fraction to be about 10% at that
frequency. We also find that the nonthermal spectral index is generally steeper
in regions with low thermal fraction and/or located in the outer parts of the
galaxy. In regions of high thermal fraction, the nonthermal spectral index is
flatter, and has a narrow distribution peaking at ~ -0.78 with a spread of
0.16, putting stringent constraints on the physical conditions for generation,
diffusion and energy losses of cosmic ray electrons at scales of ~ 1 kpc.Comment: 18 pages, 11 figures, Accepted for publication in MNRA
Executive functions in adults with developmental dyslexia
Background: Executive functioning (EF) deficits are well recognized in developmental dyslexia, yet the majority of studies have concerned children rather than adults, ignored the subjective experience of the individual with dyslexia (with regard to their own EFs), and have not followed current theoretical perspectives on EFs.
Aims and Methods: The current study addressed these shortfalls by administering a self-report measure of EF (BRIEF-A; Roth, Isquith & Gioia, 2005) and experimental tasks to IQ-matched groups of adults with and without dyslexia. The laboratory-based tasks tested the three factors constituting the framework of EF proposed by Miyake et al. (2000).
Results: In comparison to the group without dyslexia, the participants with dyslexia self-reported more frequent EF problems in day-to-day life, with these difficulties centering on metacognitive processes (working memory, planning, task monitoring, and organization) rather than on the regulation of emotion and behaviour. The participants with dyslexia showed significant deficits in EF (inhibition, set shifting, and working memory).
Conclusions and Implications: The findings indicated that dyslexia-related problems have an impact on the daily experience of adults with the condition. Further, EF difficulties are present in adulthood across a range of laboratory-based measures, and, given the nature of the experimental tasks presented, extend beyond difficulties related solely to phonological processing
Alkalizing Reactions Streamline Cellular Metabolism in Acidogenic Microorganisms
An understanding of the integrated relationships among the principal cellular functions that govern the bioenergetic reactions of an organism is necessary to determine how cells remain viable and optimise their fitness in the environment. Urease is a complex enzyme that catalyzes the hydrolysis of urea to ammonia and carbonic acid. While the induction of urease activity by several microorganisms has been predominantly considered a stress-response that is initiated to generate a nitrogen source in response to a low environmental pH, here we demonstrate a new role of urease in the optimisation of cellular bioenergetics. We show that urea hydrolysis increases the catabolic efficiency of Streptococcus thermophilus, a lactic acid bacterium that is widely used in the industrial manufacture of dairy products. By modulating the intracellular pH and thereby increasing the activity of β-galactosidase, glycolytic enzymes and lactate dehydrogenase, urease increases the overall change in enthalpy generated by the bioenergetic reactions. A cooperative altruistic behaviour of urease-positive microorganisms on the urease-negative microorganisms within the same environment was also observed. The physiological role of a single enzymatic activity demonstrates a novel and unexpected view of the non-transcriptional regulatory mechanisms that govern the bioenergetics of a bacterial cell, highlighting a new role for cytosol-alkalizing biochemical pathways in acidogenic microorganisms
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