Riosjessen2897

The superficial interneurons, SINs, of the zebrafish tectum, have been implicated in a range of visual functions, including size discrimination, directional selectivity, and looming-evoked escape. This raises the question if SIN subpopulations, despite their morphological similarities and shared anatomical position in the retinotectal processing stream, carry out diverse, task-specific functions in visual processing, or if they have simple tuning properties in common. Here we have further characterized the SINs through functional imaging, electrophysiological recordings, and neurotransmitter typing in two transgenic lines, the widely used Gal4s1156t and the recently reported LCRRH2-RH2-2GFP. We found that about a third of the SINs strongly responded to changes in whole-field light levels, with a strong preference for OFF over ON stimuli. Interestingly, individual SINs were selectively tuned to a diverse range of narrow luminance decrements. Overall responses to whole-field luminance steps did not vary with the position of the SIN cell body along the depth of the tectal neuropil or with the orientation of its neurites. We ruled out the possibility that intrinsic photosensitivity of Gal4s1156t+ SINs contribute to the measured visual responses. We found that, while most SINs express GABAergic markers, a substantial minority express an excitatory neuronal marker, the vesicular glutamate transporter, expanding the possible roles of SIN function in the tectal circuitry. In conclusion, SINs represent a molecularly, morphologically, and functionally heterogeneous class of interneurons, with subpopulations that detect a range of specific visual features, to which we have now added narrow luminance decrements.Acetylcholinesterase (AChE, EC 3.1.1.7) plays important roles in cholinergic neurotransmission and has been widely recognized as a biomarker for monitoring pollution by organophosphate (OP) and carbamate pesticides. Dioxin is an emerging environmental AChE disruptor and is a typical persistent organic pollutant with multiple toxic effects on the nervous system. Growing evidence has shown that there is a significant link between dioxin exposure and neurodegenerative diseases and neurodevelopmental disorders, most of which involve AChE and cholinergic dysfunctions. Therefore, an in-depth understanding of the effects of dioxin on AChE and the related mechanisms of action might help to shed light on the molecular bases of dioxin impacts on the nervous system. In the past decade, the effects of dioxins on AChE have been revealed in cultured cells of different origins and in rodent animal models. Unlike OP and carbamate pesticides, dioxin-induced AChE disturbance is not due to direct inhibition of enzymatic activity; instead, dioxin causes alterations of AChE expression in certain models. As a widely accepted mechanism for most dioxin effects, the aryl hydrocarbon receptor (AhR)-dependent pathway has become a research focus in studies on the mechanism of action of dioxin-induced AChE dysregulation. this website In this mini-review, the effects of dioxin on AChE and the diverse roles of the AhR pathway in AChE regulation are summarized. Additionally, the involvement of AhR in AChE regulation during different neurodevelopmental processes is discussed. These AhR-related findings might also provide new insight into AChE regulation triggered by diverse xenobiotics capable of interacting with AhR.

Previous research has shown that pre-service teachers have low responsibility for student motivation and feel underprepared to deal with motivational issues. As an extension, researchers have designed interventions to shift teachers' beliefs about motivation or equip them with approaches to instruction, but never both.

Following best practices for motivation interventions, we created a one-session online intervention and tested its efficacy to shift pre-service teachers' self-reported beliefs and approaches to instruction to be more supportive of student motivation. The intervention included priming, materials designed for mindsets and/or for approaches to instruction, a consolidation activity, and take-home materials.

A convenience sample of 384 pre-service teachers from one Canadian university participated.

We embedded an experimental design into multiple sections of a required assessment course. After completing a pre-test, participants were randomly assigned to one of four conditions beliefs-only, approaches-only, combined beliefs and approaches, or control. After completing the online module, students received a lecture on assessment practices and motivation.

The results from our MANCOVA showed that pre-service teachers who participated in the beliefs-only condition reported increased levels of responsibility for student motivation, more growth mindset beliefs, and less fixed mindset beliefs than participants in the other conditions. The approaches-only condition did not influence self-reported mastery or performance approaches to instruction and the combined condition had no effect on beliefs or approaches.

We discuss the implications for educating pre-service teachers about student motivation and suggest that beliefs and approaches to instruction need to be addressed separately.

We discuss the implications for educating pre-service teachers about student motivation and suggest that beliefs and approaches to instruction need to be addressed separately.Amyloid-β (Aβ) peptide aggregation into soluble oligomers and insoluble plaques is a precipitating event in the pathogenesis of Alzheimer's disease (AD). Given that synaptic activity can regulate Aβ generation, we postulated that 5HT2A -Rs may regulate Aβ as well. We treated APP/PS1 transgenic mice with the selective 5HT2A inverse agonists M100907 or Pimavanserin systemically and measured brain interstitial fluid (ISF) Aβ levels in real-time using in vivo microdialysis. Both compounds reduced ISF Aβ levels by almost 50% within hours, but had no effect on Aβ levels in 5HT2A -R knock-out mice. The Aβ-lowering effects of Pimavanserin were blocked by extracellular-regulated kinase (ERK) and NMDA receptor inhibitors. Chronic administration of Pimavanserin by subcutaneous osmotic pump to aged APP/PS1 mice significantly reduced CSF Aβ levels and Aβ pathology and improved cognitive function in these mice. Pimavanserin is FDA-approved to treat Parkinson's disease psychosis, and also has been shown to reduce psychosis in a variety of other dementia subtypes including Alzheimer's disease.