Interrelation and dynamic activity of visceral muscle and nerve cells from insect embryos in long-term cultures

1972 ◽  
Vol 3 (1) ◽  
pp. 3-23 ◽  
Author(s):  
L. Aloe ◽  
R. Levi-Montalcini
Keyword(s):  
Nerve Cells ◽  
Dynamic Activity ◽  
Visceral Muscle ◽  
Insect Embryos

A Problem of Long - Term Digital Preservation: Difference in Humanities and Natural Sciences

2014 ◽  
Vol 3 ◽  
pp. 183-195
Author(s):  
Elena Macevičiūtė
Keyword(s):  
Social Sciences ◽  
Digital Preservation ◽  
Dynamic Activity ◽  
Private Companies ◽  
Time Line ◽  
Digital Documents ◽  
Whole Process ◽  
The Difference ◽  
Technological Science

The article deals with the requirements and needs for long-term digital preservation in different areas of scholarly work. The concept of long-term digital preservation is introduced by comparing it to digitization and archiving concepts and defined with the emphasis on dynamic activity within a certain time line. The structure of digital preservation is presented with regard to the elements of the activity as understood in Activity Theory. The life-cycle of digitization processes forms the basis of the main processing of preserved data in preservation archival system.The author draws on the differences between humanities and social sciences on one hand and natural and technological science on the other. The empirical data characterizing the needs for digital preservation within different areas of scholarship are presented and show the difference in approaches to long-term digital preservation, as well as differences in selecting the items and implementing the projects of digital preservation. Institutions and organizations can also develop different understanding of preservation requirements for digital documents and other objects.The final part of the paper is devoted to some general problems pertaining to the longterm digital preservation with the emphasis of the responsibility for the whole process of safe-guarding the cultural and scholarly heritage for the re-use of the posterior generations. It is suggested that the longevity of the libraries in comparison with much shorter life-span of private companies strengthens the claim of memory institutions to playing the central role in the long-term digital preservation.

Frequency selectivity, multistability, and oscillations emerge from models of genetic regulatory systems

1998 ◽  
Vol 274 (2) ◽  
pp. C531-C542 ◽  
Author(s):  
Paul Smolen ◽  
Douglas A. Baxter ◽  
John H. Byrne
Keyword(s):  
Cellular Response ◽  
Cultured Cells ◽  
Computational Approach ◽  
Long Term Memory ◽  
Mrna Levels ◽  
Complex Dynamic ◽  
Dynamic Activity ◽  
Regulatory Systems ◽  
Complex Models

To examine the capability of genetic regulatory systems for complex dynamic activity, we developed simple kinetic models that incorporate known features of these systems. These include autoregulation and stimulus-dependent phosphorylation of transcription factors (TFs), dimerization of TFs, crosstalk, and feedback. The simplest model manifested multiple stable steady states, and brief perturbations could switch the model between these states. Such transitions might explain, for example, how a brief pulse of hormone or neurotransmitter could elicit a long-lasting cellular response. In slightly more complex models, oscillatory regimes were identified. The addition of competition between activating and repressing TFs provided a plausible explanation for optimal stimulus frequencies that give maximal transcription. Such optimal frequencies are suggested by recent experiments comparing training paradigms for long-term memory formation and examining changes in mRNA levels in repetitively stimulated cultured cells. In general, the computational approach illustrated here, combined with appropriate experiments, provides a conceptual framework for investigating the function of genetic regulatory systems.

PROPERTIES OF A SET OF INTERNAL RECEPTORS IN THE MEDICINAL LEECH: THE NEPHRIDIAL NERVE CELLS MONITOR EXTRACELLULAR CHLORIDE CONCENTRATION

1989 ◽  
Vol 143 (1) ◽  
pp. 115-132 ◽  
Author(s):  
ANGELA WENNING
Keyword(s):  
Ion Homeostasis ◽  
Chloride Concentration ◽  
Dendritic Tree ◽  
Medicinal Leech ◽  
Nerve Cells ◽  
Control Factor ◽  
Intracellular Recordings ◽  
Extracellular Recordings ◽  
Cl Conductance

In the leech, Hirudo medicinalis, the functional properties of the peripheral nephridial nerve cells (NNCs) were investigated using long-term extracellular recordings from both intact and isolated preparations The NNCs respond selectively to changes in external Cl− concentration: their electrical activity is highest in fluid containing normal (i.e. low) extracellular [Cl−]. Their sensitivity to Cl− is confined to the dendritic tree. Extracellular [Cl−] is a control factor for ion homeostasis. It increases drastically after a blood meal, and after the animal has left the water or invaded brackish water. The NNCs continuously monitor the extracellular Cl− concentration: their burst rate changes, without adapting, by a factor of 4 in the physiological range between 40 and 90 mmoll−1. Intracellular recordings from the NNC in isolated nephridial complexes suggest that a high Cl− conductance in combination with active transport of Cl− could be responsible for the observed Cl− sensitivitys

rhEPO Enhances Cellular Anti-oxidant Capacity to Protect Long-Term Cultured Aging Primary Nerve Cells

2017 ◽  
Vol 62 (3-4) ◽  
pp. 291-303 ◽  
Author(s):  
Huqing Wang ◽  
Jiaxin Fan ◽  
Mengyi Chen ◽  
Qingling Yao ◽  
Zhen Gao ◽  
...  
Keyword(s):  
Nerve Cells ◽  
Anti Oxidant

scholarly journals Temporally-precise basolateral amygdala activation is required for the formation of taste memories in gustatory cortex

2020 ◽  
Author(s):  
Elor Arieli ◽  
Ron Gerbi ◽  
Mark Shein-Idelson ◽  
Anan Moran
Keyword(s):  
Basolateral Amygdala ◽  
Time Lag ◽  
Nucleus Basalis ◽  
Electrophysiological Recording ◽  
Long Term Memory ◽  
Projection Neurons ◽  
Dynamic Activity ◽  
Gustatory Cortex ◽  
Taste Experience

AbstractLearning to associate malaise with the intake of novel food is critical for survival. Since food poisoning may take hours to affect, animals developed brain circuits to transform the current novel taste experience into a taste memory trace (TMT) and bridge this time lag. Ample studies showed that the basolateral amygdala (BLA), the nucleus basalis magnocellularis (NBM) and the gustatory cortex (GC) are involved in TMT formation and taste-malaise association. However, how dynamic activity across these brain regions during novel taste experience promotes the formation of these memories is currently unknown. We used the conditioned taste aversion (CTA) learning paradigm in combination with short-term optogenetics and electrophysiological recording in rats to test the hypothesis that temporally specific activation of BLA projection neurons is essential for TMT formation in the GC, and consequently CTA. We found that late-epoch (LE, >800ms), but not the early epoch (EE, 200-700ms), BLA activation during novel taste experience is essential for normal CTA, for early c-Fos expression in the GC (a marker of TMT formation) and for the subsequent changes in GC ensemble palatability coding. Interestingly, BLA activity was not required for intact taste identity or palatability perceptions. We further show that BLA-LE information is transmitted to GC through the BLA→NBM pathway where it affects the formation of taste memories. These results expose the dependence of long-term memory formation on specific temporal windows during sensory responses and the distributed circuits supporting this dependence.SignificanceConsumption of a novel taste may result in malaise and poses a threat to animals. Since the effects of poisoning appear only hours after consumption, animals must store the novel taste’s information in memory until they associate it with its value (nutritious or poisonous). Here we elucidate the neuronal activity patterns and circuits that support the processing and creation of novel-taste memories in rats. Our results show that specific patterns of temporal activation in the basolateral amygdala transmitted across brain areas are important for formation of taste memory and taste-malaise association. These findings may shed light on long-term activity-to-memory transformation in other sensory modalities.

scholarly journals Advances in Fetal Neurophysiology

2008 ◽  
Vol 2 (3) ◽  
pp. 19-34 ◽  
Author(s):  
Maja Predojevic ◽  
Aida Salihagic Kadic
Keyword(s):  
Brain Function ◽  
State Of The Art ◽  
Sensory System ◽  
Nerve Cells ◽  
Long Term Effects ◽  
Intrauterine Life ◽  
Period 2 ◽  
The Central Nervous System ◽  
The Brain

Abstract The human brain function is certainly one of the most amazing phenomena known. All behavior is the result of the brain function. The 100 billion nerve cells are the home to our centers of feelings and senses, pleasure and satisfaction; it is where the centers for learning, memory and creative work are located; where laughing and crying areas and the centers of our mind are. Our cognitive functions, such as thinking, speaking or creating works of art and science, all reside within the cerebral cortex. One of the tasks of the neural science is to explain how the brain marshals its millions of individual nerve cells to produce behavior and how these cells are affected by the environment.1 The brain function still remains shrouded in a veil of mystery. But what is known is that over 99 percent of the human neocortex is produced during the fetal period.2 Owing to the employment of state-of-the-art methods and techniques in prenatal investigations, a growing pool of information on the development of the central nervous system (CNS) and behavioral patterns during intrauterine life has been made available. This review outlines these events, along with the development of the fetal sensory system and circadian rhythms, the senses of vision and hearing, fetal learning and memory, and long-term effects of fetal stress on behavior. In brief, this review offers a glimpse of the fascinating world of the intrauterine life.

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