scholarly journals Cellular and System Biology of Memory: Timing, Molecules, and Beyond

2016 ◽  
Vol 96 (2) ◽  
pp. 647-693 ◽  
Author(s):  
Martin Korte ◽  
Dietmar Schmitz
Keyword(s):  
Structural Changes ◽  
Cell Types ◽  
Information Storage ◽  
Memory Storage ◽  
System Level ◽  
Time Range ◽  
Long Term Memory ◽  
Molecular Events ◽  
Multistep Process ◽  
Long Time

The storage of information in the mammalian nervous systems is dependent on a delicate balance between change and stability of neuronal networks. The induction and maintenance of processes that lead to changes in synaptic strength to a multistep process which can lead to long-lasting changes, which starts and ends with a highly choreographed and perfectly timed dance of molecules in different cell types of the central nervous system. This is accompanied by synchronization of specific networks, resulting in the generation of characteristic “macroscopic” rhythmic electrical fields, whose characteristic frequencies correspond to certain activity and information-processing states of the brain. Molecular events and macroscopic fields influence each other reciprocally. We review here cellular processes of synaptic plasticity, particularly functional and structural changes, and focus on timing events that are important for the initial memory acquisition, as well as mechanisms of short- and long-term memory storage. Then, we cover the importance of epigenetic events on the long-time range. Furthermore, we consider how brain rhythms at the network level participate in processes of information storage and by what means they participating in it. Finally, we examine memory consolidation at the system level during processes of sleep.

A study of the molecular–cellular interface in visual photoreceptors by light scattering photometry

1985 ◽  
Vol 63 (7) ◽  
pp. 1933-1939 ◽  
Author(s):  
T. Borys ◽  
S. Deshpande ◽  
R. Jones ◽  
E. W. Abrahamson
Keyword(s):  
Light Scattering ◽  
Structural Changes ◽  
Time Range ◽  
Relaxation Techniques ◽  
Cell Organelles ◽  
Whole Cells ◽  
Cellular Events ◽  
Molecular Events ◽  
Cytological Changes ◽  
Non Destructive

The correlation of molecular events with structural changes within the cell requires a non-destructive relaxation technique that can be adapted to measure such cellular changes in a time range of milliseconds to minutes. Light scattering relaxation techniques have proved useful for such studies as they can often be measured simultaneously or in parallel with absorption or fluorescence spectral changes characterizing molecular or macromolecular processes. Such techniques are proving useful in the study of photobiological processes such as visual photoreception where specific cytological changes produced photochemically can be effected by alternate controlled perturbations such as osmotic shrinking or swelling of cell organelles and (or) whole cells. This paper illustrates how light scattering relaxation spectrophotometry can be applied to the correlation of molecular and cellular events in visual photoreceptors.

scholarly journals Gradation (approx. 10 size states) of synaptic strength by quantal addition of structural modules

2017 ◽  
Vol 372 (1715) ◽  
pp. 20160328 ◽  
Author(s):  
Kang K. L. Liu ◽  
Michael F. Hagan ◽  
John E. Lisman
Keyword(s):  
Functional Module ◽  
Late Phase ◽  
Matrix Material ◽  
Super Resolution ◽  
Long Term Potentiation ◽  
Information Storage ◽  
Homeostatic Plasticity ◽  
Memory Storage ◽  
Long Term Memory

Memory storage involves activity-dependent strengthening of synaptic transmission, a process termed long-term potentiation (LTP). The late phase of LTP is thought to encode long-term memory and involves structural processes that enlarge the synapse. Hence, understanding how synapse size is graded provides fundamental information about the information storage capability of synapses. Recent work using electron microscopy (EM) to quantify synapse dimensions has suggested that synapses may structurally encode as many as 26 functionally distinct states, which correspond to a series of proportionally spaced synapse sizes. Other recent evidence using super-resolution microscopy has revealed that synapses are composed of stereotyped nanoclusters of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors and scaffolding proteins; furthermore, synapse size varies linearly with the number of nanoclusters. Here we have sought to develop a model of synapse structure and growth that is consistent with both the EM and super-resolution data. We argue that synapses are composed of modules consisting of matrix material and potentially one nanocluster. LTP induction can add a trans-synaptic nanocluster to a module, thereby converting a silent module to an AMPA functional module. LTP can also add modules by a linear process, thereby producing an approximately 10-fold gradation in synapse size and strength. This article is part of the themed issue ‘Integrating Hebbian and homeostatic plasticity’.

scholarly journals Sleep deprivation causes memory deficits by negatively impacting neuronal connectivity in hippocampal area CA1

eLife ◽  
2016 ◽  
Vol 5 ◽  
Author(s):  
Robbert Havekes ◽  
Alan J Park ◽  
Jennifer C Tudor ◽  
Vincent G Luczak ◽  
Rolf T Hansen ◽  
...  
Keyword(s):  
Sleep Deprivation ◽  
Structural Changes ◽  
Dendritic Structure ◽  
Memory Storage ◽  
Long Term Memory ◽  
Spine Density ◽  
Recovery Sleep ◽  
Area Ca1 ◽  
Hippocampal Area ◽  
The Impact

Brief periods of sleep loss have long-lasting consequences such as impaired memory consolidation. Structural changes in synaptic connectivity have been proposed as a substrate of memory storage. Here, we examine the impact of brief periods of sleep deprivation on dendritic structure. In mice, we find that five hours of sleep deprivation decreases dendritic spine numbers selectively in hippocampal area CA1 and increased activity of the filamentous actin severing protein cofilin. Recovery sleep normalizes these structural alterations. Suppression of cofilin function prevents spine loss, deficits in hippocampal synaptic plasticity, and impairments in long-term memory caused by sleep deprivation. The elevated cofilin activity is caused by cAMP-degrading phosphodiesterase-4A5 (PDE4A5), which hampers cAMP-PKA-LIMK signaling. Attenuating PDE4A5 function prevents changes in cAMP-PKA-LIMK-cofilin signaling and cognitive deficits associated with sleep deprivation. Our work demonstrates the necessity of an intact cAMP-PDE4-PKA-LIMK-cofilin activation-signaling pathway for sleep deprivation-induced memory disruption and reduction in hippocampal spine density.

CELL AND TISSUE THERAPY OF HEART

2019 ◽  
pp. 77-84
Keyword(s):  
Extracellular Matrix ◽  
Cell Types ◽  
Heart Tissue ◽  
Decellularized Extracellular Matrix ◽  
Tissue Therapy ◽  
Essential Components ◽  
Long Time ◽  
Different Populations ◽  
A Site ◽  
Recipient Tissue

The strategy of heart tissue engineering is simple enough: first remove all the cells from a organ then take the protein scaffold left behind and repopulate it with stem cells immunologically matched to the patient in need. While various suc- cessful methods for decellularization have been developed, and the feasibility of using decellularized whole hearts and extracellular matrix to support cells has been demonstrated, the reality of creating whole hearts for transplantation and of clinical application of decellularized extracellular matrix-based scaffolds will require much more research. For example, further investigations into how lineage-restricted progenitors repopulate the decellularized heart and differentiate in a site-specific manner into different populations of the native heart would be essential. The scaffold heart does not have to be human. Pig hearts carries all the essential components of the extracellular matrix. Through trial and error, scaling up the concentration, timing and pressure of the detergents, researchers have refined the decellularization process on hundreds of hearts and other organs, but this is only the first step. Further, the framework must be populated with human cells. Most researchers in the field use a mixture of two or more cell types, such as endothelial precursor cells to line blood vessels and muscle progenitors to seed the walls of the chambers. The final challenge is one of the hardest: vasculariza- tion, placing a engineered heart into a living animal, integration with the recipient tissue, and keeping it beating for a long time. Much remains to be done before a bioartificial heart is available for transplantation in humans.

Neuronal mRNA Translation in Addiction

2018 ◽  
Author(s):  
Emma Puighermanal ◽  
Emmanuel Valjent
Keyword(s):  
Structural Changes ◽  
Drugs Of Abuse ◽  
Mrna Translation ◽  
Cell Types ◽  
Behavioral Changes ◽  
Translational Machinery ◽  
Addictive Drugs ◽  
Specific Mrnas ◽  
Cell Type Specific ◽  
Future Work

Addictive drugs trigger persistent synaptic and structural changes in the neuronal reward circuits that are thought to underlie the development of drug-adaptive behavior. While transcriptional and epigenetic modifications are known to contribute to these circuit changes, accumulating evidence indicates that altered mRNA translation is also a key molecular mechanism. This chapter reviews recent studies demonstrating how addictive drugs alter protein synthesis and/or the translational machinery and how this leads to neuronal circuit remodeling and behavioral changes. Future work will determine precisely which neuronal circuits and cell types participate in these changes. The chapter summarizes current methodologies for identifying cell type-specific mRNAs whose translation is affected by drugs of abuse and gives recent examples of the mechanistic insights into addiction they provide.

scholarly journals Pedagogical Strategies for the Enhancement of Medical Education

2021 ◽  
Author(s):  
Mohammad B. Azzam ◽  
Ronald A. Easteal
Keyword(s):  
Medical Education ◽  
Cognitive Science ◽  
Retrieval Practice ◽  
Memory Storage ◽  
Long Term Memory ◽  
Memory And Learning ◽  
Pedagogical Strategies ◽  
Term Memory ◽  
Sleep Consolidation

AbstractClearly, memory and learning are essential to medical education. To make memory and learning more robust and long-term, educators should turn to the advances in neuroscience and cognitive science to direct their efforts. This paper describes the memory pathways and stages with emphasis leading to long-term memory storage. Particular stress is placed on this storage as a construct known as schema. Leading from this background, several pedagogical strategies are described: cognitive load, dual encoding, spiral syllabus, bridging and chunking, sleep consolidation, and retrieval practice.

scholarly journals FRI0632-HPR PSYCHOLOGICAL PARTICULIARITIES OF PATIENTS SUFFERING FROM MONOGENIC AUTO-INFLAMMATORY DISEASES.

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 920.1-921
Author(s):  
N. Stepanenko ◽  
E. Fedorov ◽  
S. Salugina ◽  
S. Feoktistova
Keyword(s):  
Inflammatory Diseases ◽  
Life Quality ◽  
Information Storage ◽  
Social Adaptation ◽  
Long Term Memory ◽  
Short Term ◽  
Sequence Of Events ◽  
Communicative Disorders ◽  
Negative Effect ◽  
High Level

Background:Monogenic auto-inflammatory diseases (mAID) are a group of severe chronic multisystemic diseases with recurring episodes of fever and other manifestations that significantly affect the patients’ life quality. Moreover, the hyper expression of pro-inflammatory cytokines (IL1β, etc.) observed in these patients may have a negative effect on the central nervous system.Objectives:to study the state of the cognitive and emotional spheres in children suffering from monogenic auto-inflammatory diseases.Methods:there were examined 22 children at the age of 7 to 17 years old diagnosed with CAPS-9, TRAPS-8, FMF-5. Among them there were 12 boys and 10 girls. The diagnosis in all the patients was confirmed through detection of pathogenic mutations in the NLRP3, TNFRSF1A and MEFV genes. The following methods were used: a clinical conversation; memory diagnostics (learning by heart of 10 words, a pictogram using cues taking into account the patients’ age); attention diagnostics (Schulte tables); thinking diagnostics (establishing a sequence of events, “four is a crwod”, simple analogies, interpretation of proverbs); emotional and communicative fields (the Eight-Color Luscher Test; CMAS (adaptation by A. Prikhozhan); STAI test, a drawing called “an animal that does not exist” and “a house-a tree-a man”).Results:The memory study revealed in all patients with TRAPS and FMF high and medium values of short-term and long-term memory, in patients with CAPS - a low level of short-term auditory-speech memory, information storage and indirect memorization in 1/3 of patients. In 100% of the examined patients with TRAPS, a significant decrease in all processes of attention and distribution of attention. In 1/3 of patients with CAPS, an increased exhaustion of attention was registered and in 11% - a decrease in its stability. In patients with FMF, attention disorders were not detected. In 44% of patients with CAPS, a decrease in the level of generalization and difficulties in establishing causal relationships were registered. In 25% of patients with TRAPS a decrease in the level of generalization, in 12.5%- difficulties in establishing cause-effect relationships, inertia of thinking in 37.5%. In 60% of patients with FMF: a decrease in the level of generalization, in 80%: difficulties in establishing cause-effect relationships, inertia of thinking in 20%. In the emotional sphere, patients with CAPS, TRAPS, and FMF demonstrated signs of aggression (11.1%, 20% and 20% of patients, respectively), communicative disorders (77.8% -80% - 80%), and reduced social adaptation (55.5% - 80% - 80%), a tendency to form neurotic fears (22% - 40% - 40%). A high level of personal anxiety was noted in 1/3 of patients with CAPS and 40% of patients with FMF.Conclusion:various psychological disorders in the cognitive and emotional fields were noted in the majority of the examined patients with monogenic auto-inflammatory diseases. In patients with TRAPS, attention processes are most significantly affected; in patients with CAPS, memory is more often affected. In patients with FMF, disorders in thinking processes are revealed more often. In the emotional sphere, most patients with all the three forms of AID note communicative disorders and social adaptation.Disclosure of Interests:None declared

scholarly journals Extraneous E-Cadherin Engages the Deterministic Process of Somatic Reprogramming through Modulating STAT3 and Erk1/2 Activity

Cells ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 284
Author(s):  
Yu-Hao Liu ◽  
Chien-Chang Chen ◽  
Yi-Jen Hsueh ◽  
Li-Man Hung ◽  
David Hui-Kang Ma ◽  
...  
Keyword(s):  
Stochastic Process ◽  
Molecular Mechanism ◽  
Activity Ratio ◽  
Cell Types ◽  
Deterministic Process ◽  
Modes Of Action ◽  
Molecular Events ◽  
Different Cell Types ◽  
Selection Of ◽  
E Cadherin

Although several modes of reprogramming have been reported in different cell types during iPSC induction, the molecular mechanism regarding the selection of different modes of action is still mostly unknown. The present study examined the molecular events that participate in the selection of such processes at the onset of somatic reprogramming. The activity of STAT3 versus that of Erk1/2 reversibly determines the reprogramming mode entered; a lower activity ratio favors the deterministic process and vice versa. Additionally, extraneous E-cadherin facilitates the early events of somatic reprogramming, potentially by stabilizing the LIF/gp130 and EGFR/ErbB2 complexes to promote entry into the deterministic process. Our current findings demonstrated that manipulating the pSTAT3/pErk1/2 activity ratio in the surrounding milieu can drive different modes of action toward either the deterministic or the stochastic process in the context of OSKM-mediated somatic reprogramming.

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