421 research outputs found

    Multivariate meta-analyses of mitochondrial complex I and IV in major depressive disorder, bipolar disorder, schizophrenia, Alzheimer disease, and Parkinson disease

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    Complex I (NADH dehydrogenase, NDU) and complex IV (cytochrome-c-oxidase, COX) of the mitochondrial electron transport chain have been implicated in the pathophysiology of major psychiatric disorders, such as major depressive disorder (MDD), bipolar disorder (BD), and schizophrenia (SZ), as well as in neurodegenerative disorders, such as Alzheimer disease (AD) and Parkinson disease (PD). We conducted meta-analyses comparing complex I and IV in each disorder MDD, BD, SZ, AD, and PD, as well as in normal aging. The electronic databases Pubmed, EMBASE, CENTRAL, and Google Scholar, were searched for studies published between 1980 and 2018. Of 2049 screened studies, 125 articles were eligible for the meta-analyses. Complex I and IV were assessed in peripheral blood, muscle biopsy, or postmortem brain at the level of enzyme activity or subunits. Separate meta-analyses of mood disorder studies, MDD and BD, revealed moderate effect sizes for similar abnormality patterns in the expression of complex I with SZ in frontal cortex, cerebellum and striatum, whereas evidence for complex IV alterations was low. By contrast, the neurodegenerative disorders, AD and PD, showed strong effect sizes for shared deficits in complex I and IV, such as in peripheral blood, frontal cortex, cerebellum, and substantia nigra. Beyond the diseased state, there was an age-related robust decline in both complexes I and IV. In summary, the strongest support for a role for complex I and/or IV deficits, is in the pathophysiology of PD and AD, and evidence is less robust for MDD, BD, or SZ

    performance: An R package for assessment, comparison and testing of statistical models

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    A crucial part of statistical analysis is evaluating a model’s quality and fit, or performance. During analysis, especially with regression models, investigating the fit of models to data also often involves selecting the best fitting model amongst many competing models. Upon investigation, fit indices should also be reported both visually and numerically to bring readers in on the investigative effort. The performance R-package (R Core Team, 2021) provides utilities for computing measures to assess model quality, many of which are not directly provided by R’s base or stats packages. These include measures like R2, intraclass correlation coefficient (ICC), root mean squared error (RMSE), or functions to check for vexing issues like overdispersion, singularity, or zeroinflation. These functions support a large variety of regression models including generalized linear models, (generalized) mixed-effects models, their Bayesian cousins, and many others

    Induced pluripotent stem cells from hair follicles as a cellular model for neurodevelopmental disorders

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    AbstractDisease-specific induced pluripotent stem cells (iPSC) allow unprecedented experimental platforms for basic research as well as high-throughput screening. This may be particularly relevant for neuropsychiatric disorders, in which the affected neuronal cells are not accessible. Keratinocytes isolated from hair follicles are an ideal source of patients' cells for reprogramming, due to their non-invasive accessibility and their common neuroectodermal origin with neurons, which can be important for potential epigenetic memory. From a small number of plucked human hair follicles obtained from two healthy donors we reprogrammed keratinocytes to pluripotent iPSC. We further differentiated these hair follicle-derived iPSC to neural progenitors, forebrain neurons and functional dopaminergic neurons.This study shows that human hair follicle-derived iPSC can be differentiated into various neural lineages, suggesting this experimental system as a promising in vitro model to study normal and pathological neural developments, avoiding the invasiveness of commonly used skin biopsies

    Sp1 Expression Is Disrupted in Schizophrenia; A Possible Mechanism for the Abnormal Expression of Mitochondrial Complex I Genes, NDUFV1 and NDUFV2

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    The prevailing hypothesis regards schizophrenia as a polygenic disease, in which multiple genes combine with each other and with environmental stimuli to produce the variance of its clinical symptoms. We investigated whether the ubiquitous transcription factor Sp1 is abnormally expressed in schizophrenia, and consequently can affect the expression of genes implicated in this disorder. promoter by binding to its three GC-boxes. Both activation and binding were inhibited by mithramycin.These findings suggest that abnormality in Sp1, which can be the main activator/repressor or act in combination with additional transcription factors and is subjected to environmental stimuli, can contribute to the polygenic and clinically heterogeneous nature of schizophrenia

    Rapid online assessment of reading ability

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    Published18 March 2021An accurate model of the factors that contribute to individual differences in reading ability depends on data collection in large, diverse and representative samples of research participants. However, that is rarely feasible due to the constraints imposed by standardized measures of reading ability which require test administration by trained clinicians or researchers. Here we explore whether a simple, two-alternative forced choice, time limited lexical decision task (LDT), self-delivered through the webbrowser, can serve as an accurate and reliable measure of reading ability. We found that performance on the LDT is highly correlated with scores on standardized measures of reading ability such as the Woodcock-Johnson Letter Word Identification test (r = 0.91, disattenuated r = 0.94). Importantly, the LDT reading ability measure is highly reliable (r = 0.97). After optimizing the list of words and pseudowords based on item response theory, we found that a short experiment with 76 trials (2–3 min) provides a reliable (r = 0.95) measure of reading ability. Thus, the self-administered, Rapid Online Assessment of Reading ability (ROAR) developed here overcomes the constraints of resourceintensive, in-person reading assessment, and provides an efficient and automated tool for effective online research into the mechanisms of reading (dis)ability.We would like to thank the Pavlovia and PsychoPy team for their support on the browser-based experiments. This work was funded by NIH NICHD R01HD09586101, research grants from Microsoft and Jacobs Foundation Research Fellowship to J.D.Y

    Neuroanatomical Pattern of Mitochondrial Complex I Pathology Varies between Schizophrenia, Bipolar Disorder and Major Depression

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    BACKGROUND:Mitochondrial dysfunction was reported in schizophrenia, bipolar disorderand major depression. The present study investigated whether mitochondrial complex I abnormalities show disease-specific characteristics. METHODOLOGY/PRINCIPAL FINDINGS:mRNA and protein levels of complex I subunits NDUFV1, NDUFV2 and NADUFS1, were assessed in striatal and lateral cerebellar hemisphere postmortem specimens and analyzed together with our previous data from prefrontal and parieto-occipital cortices specimens of patients with schizophrenia, bipolar disorder, major depression and healthy subjects. A disease-specific anatomical pattern in complex I subunits alterations was found. Schizophrenia-specific reductions were observed in the prefrontal cortex and in the striatum. The depressed group showed consistent reductions in all three subunits in the cerebellum. The bipolar group, however, showed increased expression in the parieto-occipital cortex, similar to those observed in schizophrenia, and reductions in the cerebellum, yet less consistent than the depressed group. CONCLUSIONS/SIGNIFICANCE:These results suggest that the neuroanatomical pattern of complex I pathology parallels the diversity and similarities in clinical symptoms of these mental disorders

    SNPs and real-time quantitative PCR method for constitutional allelic copy number determination, the VPREB1 marker case

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    <p>Abstract</p> <p>Background</p> <p>22q11.2 microdeletion is responsible for the DiGeorge Syndrome, characterized by heart defects, psychiatric disorders, endocrine and immune alterations and a 1 in 4000 live birth prevalence. Real-time quantitative PCR (qPCR) approaches for allelic copy number determination have recently been investigated in 22q11.2 microdeletions detection. The qPCR method was performed for 22q11.2 microdeletions detection as a first-level screening approach in a genetically unknown series of patients with congenital heart defects. A technical issue related to the <it>VPREB1 </it>qPCR marker was pointed out.</p> <p>Methods</p> <p>A set of 100 unrelated Italian patients with congenital heart defects were tested for 22q11.2 microdeletions by a qPCR method using six different markers. Fluorescence In Situ Hybridization technique (FISH) was used for confirmation.</p> <p>Results</p> <p>qPCR identified six patients harbouring the 22q11.2 microdeletion, confirmed by FISH. The <it>VPREB1 </it>gene marker presented with a pattern consistent with hemideletion in one 3 Mb deleted patient, suggestive for a long distal deletion, and in additional five non-deleted patients. The long distal 22q11.2 deletion was not confirmed by Comparative Genomic Hybridization. Indeed, the <it>VPREB1 </it>gene marker generated false positive results in association with the rs1320 G/A SNP, a polymorphism localized within the <it>VPREB1 </it>marker reverse primer sequence. Patients heterozygous for rs1320 SNP, showed a qPCR profile consistent with the presence of a hemideletion.</p> <p>Conclusions</p> <p>Though the qPCR technique showed advantages as a screening approach in terms of cost and time, the <it>VPREB1 </it>marker case revealed that single nucleotide polymorphisms can interfere with qPCR data generating erroneous allelic copy number interpretations.</p
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