Methylated Cytosine and the Brain A New Base for Neuroscience

AbstractMethylation of genomic CpG residues is crucial for proper neuronal function. Rett syndrome, a common form of mental retardation, is associated with mutations in the gene encoding MeCP2, a methyl CpG binding protein linked to transcriptional repression. Gene knockouts of mouse Mecp2 have reproduced key aspects of the disease. A CNS-restricted knockout of Dnmt1, encoding the enzyme that maintains CpG methylation patterns, results in loss of mutant neurons and glia

A genetic investigation of the establishment of genomic imprinting

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Biology, 1997.Includes bibliographical references.by Kerry Lee Tucker.Ph.D

Positional Cloning of cobblestone, a Mouse Mutant Showing Major Defects in Brain Development, Identifies Ift88 as a Candidate Gene

The ENU-induced cobblestone (cbs) mouse mutant exhibits severe defects in fore- and midbrain development. Via genomic mapping, the causative mutation for the cbs-phenotype has previously been located on chromosome 14 in the proximity of the gene Ift88 (Intraflagellar transport, 88 kDa). The Ift88 protein is involved in intraflagellar transport and is required for genesis and maintenance of primary and motile cilia. In order to refine the genetic interval further, we performed fine-mapping analysis of the cbs mutant. The candidate region of the cbs mutation is shown to be situated in a region of 4.14 Mb on chromosome 14, containing the Ift88 gene, and excluding dozens of genes present in the roughly-mapped interval. However, neither sequencing of the core Ift88 promoter region nor of two conserved intronic sequences within Ift88 revealed any mutations, indicating that the responsible mutation lies in a transcriptional regulatory sequence within or near the Ift88 gene. Finally, other potential candidate genes in this genetic interval have been identified using synteny analysis on six other vertebrate genomes. This analysis is thus compatible with the idea that the mutation in cbs is located on the Ift88 gene, but it also allows the possibility of other candidate genes that lie near Ift88 to be involved in the phenotype

Evidence for a unitary structure of spatial cognition beyond general intelligence

Performance in everyday spatial orientation tasks (e.g. map reading and navigation) has been considered functionally separate from performance on more abstract object-based spatial abilities (e.g. mental rotation and visualization). However, evidence remains scarce and unsystematic. With a novel gamified battery, we assessed six tests of spatial orientation in a virtual environment and examined their association with ten object-based spatial tests, as well as their links to general cognitive ability (g). We further estimated the role of genetic and environmental factors in underlying variation and covariation in these spatial tests. Participants (N = 2,660) were part of the Twins Early Development Study, aged 19 to 22. The 6 tests of spatial orientation clustered into a single ‘Navigation’ factor that was 64% heritable. Examining the structure of spatial ability across all 16 tests, three factors emerged: Navigation, Object Manipulation and Visualization. These, in turn, loaded strongly onto a general factor of Spatial Ability, which was highly heritable (84%). A large portion (45%) of this high heritability was independent of g. The results from this most comprehensive investigation of spatial abilities to date point towards the existence of a common genetic network that supports all spatial abilities

Targeting of low ALK antigen density neuroblastoma using AND logic-gate engineered CAR-T cells

Background aims: The targeting of solid cancers with chimeric antigen receptor (CAR) T cells faces many technological hurdles, including selection of optimal target antigens. Promising pre-clinical and clinical data of CAR T-cell activity have emerged from targeting surface antigens such as GD2 and B7H3 in childhood cancer neuroblastoma. Anaplastic lymphoma kinase (ALK) is expressed in a majority of neuroblastomas at low antigen density but is largely absent from healthy tissues. / Methods: To explore an alternate target antigen for neuroblastoma CAR T-cell therapy, the authors generated and screened a single-chain variable fragment library targeting ALK extracellular domain to make a panel of new anti-ALK CAR T-cell constructs. / Results: A lead novel CAR T-cell construct was capable of specific cytotoxicity against neuroblastoma cells expressing low levels of ALK, but with only weak cytokine and proliferative T-cell responses. To explore strategies for amplifying ALK CAR T cells, the authors generated a co-CAR approach in which T cells received signal 1 from a first-generation ALK construct and signal 2 from anti-B7H3 or GD2 chimeric co-stimulatory receptors. The co-CAR approach successfully demonstrated the ability to avoid targeting single-antigen-positive targets as a strategy for mitigating on-target off-tumor toxicity. / Conclusions: These data provide further proof of concept for ALK as a neuroblastoma CAR T-cell target

Self-monitoring of blood pressure in hypertension: A systematic review and individual patient data meta-analysis.

BACKGROUND: Self-monitoring of blood pressure (BP) appears to reduce BP in hypertension but important questions remain regarding effective implementation and which groups may benefit most. This individual patient data (IPD) meta-analysis was performed to better understand the effectiveness of BP self-monitoring to lower BP and control hypertension. METHODS AND FINDINGS: Medline, Embase, and the Cochrane Library were searched for randomised trials comparing self-monitoring to no self-monitoring in hypertensive patients (June 2016). Two reviewers independently assessed articles for eligibility and the authors of eligible trials were approached requesting IPD. Of 2,846 articles in the initial search, 36 were eligible. IPD were provided from 25 trials, including 1 unpublished study. Data for the primary outcomes-change in mean clinic or ambulatory BP and proportion controlled below target at 12 months-were available from 15/19 possible studies (7,138/8,292 [86%] of randomised participants). Overall, self-monitoring was associated with reduced clinic systolic blood pressure (sBP) compared to usual care at 12 months (-3.2 mmHg, [95% CI -4.9, -1.6 mmHg]). However, this effect was strongly influenced by the intensity of co-intervention ranging from no effect with self-monitoring alone (-1.0 mmHg [-3.3, 1.2]), to a 6.1 mmHg (-9.0, -3.2) reduction when monitoring was combined with intensive support. Self-monitoring was most effective in those with fewer antihypertensive medications and higher baseline sBP up to 170 mmHg. No differences in efficacy were seen by sex or by most comorbidities. Ambulatory BP data at 12 months were available from 4 trials (1,478 patients), which assessed self-monitoring with little or no co-intervention. There was no association between self-monitoring and either lower clinic or ambulatory sBP in this group (clinic -0.2 mmHg [-2.2, 1.8]; ambulatory 1.1 mmHg [-0.3, 2.5]). Results for diastolic blood pressure (dBP) were similar. The main limitation of this work was that significant heterogeneity remained. This was at least in part due to different inclusion criteria, self-monitoring regimes, and target BPs in included studies. CONCLUSIONS: Self-monitoring alone is not associated with lower BP or better control, but in conjunction with co-interventions (including systematic medication titration by doctors, pharmacists, or patients; education; or lifestyle counselling) leads to clinically significant BP reduction which persists for at least 12 months. The implementation of self-monitoring in hypertension should be accompanied by such co-interventions

An Examination of Children’s Learning Progression Shifts While Using Touch Screen Virtual Manipulative Mathematics Apps

The purpose of this study was to examine shifts in young children\u27s learning progression levels while they interacted with virtual manipulative mathematics apps on touch-screen devices. A total of 100 children participated in six mathematics learning sequences while using 18 virtual manipulative mathematics touch-screen apps during clinical interviews. Researchers developed a micro-scoring tool to analyze video data from two camera sources (i.e., GoPro camera, wall-mounted camera). Our results showed that it is possible to document evidence of shifts in children\u27s learning progressions while they are interacting with mathematics apps on touch-screen devices. Our results also indicated patterns in the children\u27s interactions that were related to the shifts in their learning progression levels. These results suggest that an open-ended number of tasks with a variety of representations and tasks at varying levels of difficulty led to children refining their understanding and shaping their concept image of mathematical ideas resulting in incremental shifts in learning. The results of this study have important implications about how mathematical tasks in touch-screen apps may prompt children\u27s incremental learning progression shifts to occur, and thereby promote opportunities for learning. We propose that design features in mathematics apps can be created to support and encourage these learning shifts

The International Olympic Committee framework on fairness, inclusion and nondiscrimination on the basis of gender identity and sex variations does not protect fairness for female athletes

The International Olympic Committee (IOC) recently published a framework on fairness, inclusion, and nondiscrimination on the basis of gender identity and sex variations. Although we appreciate the IOC's recognition of the role of sports science and medicine in policy development, we disagree with the assertion that the IOC framework is consistent with existing scientific and medical evidence and question its recommendations for implementation. Testosterone exposure during male development results in physical differences between male and female bodies; this process underpins male athletic advantage in muscle mass, strength and power, and endurance and aerobic capacity. The IOC's “no presumption of advantage” principle disregards this reality. Studies show that transgender women (male-born individuals who identify as women) with suppressed testosterone retain muscle mass, strength, and other physical advantages compared to females; male performance advantage cannot be eliminated with testosterone suppression. The IOC's concept of “meaningful competition” is flawed because fairness of category does not hinge on closely matched performances. The female category ensures fair competition for female athletes by excluding male advantages. Case-by-case testing for transgender women may lead to stigmatization and cannot be robustly managed in practice. We argue that eligibility criteria for female competition must consider male development rather than relying on current testosterone levels. Female athletes should be recognized as the key stakeholders in the consultation and decision-making processes. We urge the IOC to reevaluate the recommendations of their Framework to include a comprehensive understanding of the biological advantages of male development to ensure fairness and safety in female sports

Histone Deacetylases Control Neurogenesis in Embryonic Brain by Inhibition of BMP2/4 Signaling

Background Histone-modifying enzymes are essential for a wide variety of cellular processes dependent upon changes in gene expression. Histone deacetylases (HDACs) lead to the compaction of chromatin and subsequent silencing of gene transcription, and they have recently been implicated in a diversity of functions and dysfunctions in the postnatal and adult brain including ocular dominance plasticity, memory consolidation, drug addiction, and depression. Here we investigate the role of HDACs in the generation of neurons and astrocytes in the embryonic brain. Principal Findings As a variety of HDACs are expressed in differentiating neural progenitor cells, we have taken a pharmacological approach to inhibit multiple family members. Inhibition of class I and II HDACs in developing mouse embryos with trichostatin A resulted in a dramatic reduction in neurogenesis in the ganglionic eminences and a modest increase in neurogenesis in the cortex. An identical effect was observed upon pharmacological inhibition of HDACs in in vitro-differentiating neural precursors derived from the same brain regions. A reduction in neurogenesis in ganglionic eminence-derived neural precursors was accompanied by an increase in the production of immature astrocytes. We show that HDACs control neurogenesis by inhibition of the bone morphogenetic protein BMP2/4 signaling pathway in radial glial cells. HDACs function at the transcriptional level by inhibiting and promoting, respectively, the expression of Bmp2 and Smad7, an intracellular inhibitor of BMP signaling. Inhibition of the BMP2/4 signaling pathway restored normal levels of neurogenesis and astrogliogenesis to both ganglionic eminence- and cortex-derived cultures in which HDACs were inhibited. Conclusions Our results demonstrate a transcriptionally-based regulation of BMP2/4 signaling by HDACs both in vivo and in vitro that is critical for neurogenesis in the ganglionic eminences and that modulates cortical neurogenesis. The results also suggest that HDACs may regulate the developmental switch from neurogenesis to astrogliogenesis that occurs in late gestation