Purpose: To analyze the frequency of main keratotopographic patterns at the 1, 2, and 3 stages of keratoconus and investigate corneal biomechanical properties across different patterns.
Methods: The study comprised two stages. The first stage was computational-experimental, where we utilized COMSOL Multiphysics® software (COMSOL AB, Stockholm, Sweden) to mathematically model corneal mechanical behavior under intraocular pressure and pulsed air jet action in both normal and keratoconic conditions.
Intense species-specific locomotion changes the behavioural and cognitive states of various vertebrates and invertebrates. However, whether and how reproductive behaviour is affected by previous increased motor activity remains largely unknown. We addressed this question using a model organism, the pond snail .
View Article and Find Full Text PDFFront Mol Neurosci
May 2023
Introduction: Culturing of human neural stem cells (NSCs) derived from induced pluripotent stem cells (iPSC) is a promising area of research, as these cells have the potential to treat a wide range of neurological, neurodegenerative and psychiatric diseases. However, the development of optimal protocols for the production and long-term culturing of NSCs remains a challenge. One of the most important aspects of this problem is to determine the stability of NSCs during long-term in vitro passaging.
View Article and Find Full Text PDFBenefits of physical exercise for brain functions are well documented in mammals, including humans. In this review, we will summarize recent research on the effects of species-specific intense locomotion on behavior and brain functions of different invertebrates. Special emphasis is made on understanding the biological significance of these effects as well as underlying cellular and molecular mechanisms.
View Article and Find Full Text PDFThe role of serotonin in the immediate and delayed influence of physical exercise on brain functions has been intensively studied in mammals. Recently, immediate effects of intense locomotion on the decision-making under uncertainty were reported in the Great Pond snail, (Korshunova et al., 2016).
View Article and Find Full Text PDFThe vestibular system receives a permanent influence from gravity and reflexively controls equilibrium. If we assume gravity has remained constant during the species' evolution, will its sensory system adapt to abrupt loss of that force? We address this question in the land snail exposed to 30 days of near weightlessness aboard the Bion-M1 satellite, and studied geotactic behavior of postflight snails, differential gene expressions in statocyst transcriptome, and electrophysiological responses of mechanoreceptors to applied tilts. Each approach revealed plastic changes in the snail's vestibular system assumed in response to spaceflight.
View Article and Find Full Text PDFBehavioural/motivational state is known to influence nearly all aspects of physiology and behaviour. The cellular basis of behavioural state control is only partially understood. Our investigation, performed on the pond snail Lymnaea stagnalis whose nervous system is useful for work on completely isolated neurons, provided several results related to this problem.
View Article and Find Full Text PDFBiophysics (Nagoya-shi)
August 2016
The involvement of serotonin in mediating hunger-related changes in behavioral state has been described in many invertebrates. However, the mechanisms by which hunger signals to serotonergic cells remain unknown. We tested the hypothesis that serotonergic neurons can directly sense the concentration of glucose, a metabolic indicator of nutritional state.
View Article and Find Full Text PDFBackground: The mollusk statocyst is a mechanosensing organ detecting the animal's orientation with respect to gravity. This system has clear similarities to its vertebrate counterparts: a weight-lending mass, an epithelial layer containing small supporting cells and the large sensory hair cells, and an output eliciting compensatory body reflexes to perturbations.
Methodology/principal Findings: In terrestrial gastropod snail we studied the impact of 16- (Foton M-2) and 12-day (Foton M-3) exposure to microgravity in unmanned orbital missions on: (i) the whole animal behavior (Helix lucorum L.
A family of neuropeptides called Command Neuron Peptides (CNPs) was described ten years ago as the protein products of the gene HCS2, specifically expressed in the identified interneurons of the nervous system of terrestrial snail (Helix lucorum L. and H. pomatia L.
View Article and Find Full Text PDFWe used a simple sensory and motor system to investigate the neuronal mechanisms of olfactory orientation behaviour. The main olfactory organs of terrestrial molluscs, the experimental animals used in this work, are located on the tips of their tentacles, which display complex movements when they explore a new environment. By reconstructing the trajectory of the tentacle tip ('nose') movements in three dimensions in freely moving snails, we showed that the protracted tentacles performed continuous scanning, both spontaneously and in response to odours.
View Article and Find Full Text PDF