-
Development, Growth & Differentiation May 2015Animals have an intrinsic regeneration ability for injured tissues and organs. Species that have high regeneration ability such as newts can regenerate an organ with... (Review)
Review
Animals have an intrinsic regeneration ability for injured tissues and organs. Species that have high regeneration ability such as newts can regenerate an organ with exactly the same size and shape as those of the original one. It has been unclear how a regenerating organ grows and ceases growth at an appropriate size. Organ size control in regeneration is seen in various organs of various species that have high regeneration ability. In animal species that do not have sufficient regeneration ability, a wound heals (the injury is closed, but lost parts are not regenerated), but an organ cannot be restored to its original size. On the other hand, perturbation of regeneration sometimes results in oversized or extra structures. In this sense, organ size control plays essential roles in proper regeneration. In this article, we introduce the concept of size control in organ regeneration regulated by the Hippo signaling pathway. We focused on the transcriptional regulator Yap, which shuttles between the nuclei and cytoplasm to exert a regulatory function in a context-dependent manner. The Yap-mediated Hippo pathway is thought to sense cell density, extracellular matrix (ECM) contact and cell position and to regulate gene expression for control of organ size. This mechanism can reasonably explain size control of organ regeneration.
Topics: Animals; Humans; Intracellular Signaling Peptides and Proteins; Regeneration; Signal Transduction
PubMed: 25867864
DOI: 10.1111/dgd.12212 -
Advances in Experimental Medicine and... 2018Neurobiology in ascidians has made many advances. Ascidians have offered natural advantages to researchers, including fecundity, structural simplicity, invariant... (Review)
Review
Neurobiology in ascidians has made many advances. Ascidians have offered natural advantages to researchers, including fecundity, structural simplicity, invariant morphology, and fast and stereotyped developmental processes. The researchers have also accumulated on this animal a great deal of knowledge, genomic resources, and modern genetic techniques. A recent connectomic analysis has shown an ultimately resolved image of the larval nervous system, whereas recent applications of live imaging and optogenetics have clarified the functional organization of the juvenile nervous system. Progress in resources and techniques have provided convincing ways to deepen what we have wanted to know about the nervous systems of ascidians. Here, the research history and the current views regarding ascidian nervous systems are summarized.
Topics: Action Potentials; Animals; Animals, Genetically Modified; Brain; Cell Lineage; Ciona intestinalis; Connectome; Ependyma; Forecasting; Ganglia, Invertebrate; Genes, Reporter; Imaging, Three-Dimensional; Intravital Microscopy; Larva; Muscle Cells; Nervous System; Nervous System Physiological Phenomena; Neurogenesis; Neurons; Optogenetics; Sense Organs; Swimming; Tail; Urochordata
PubMed: 29542090
DOI: 10.1007/978-981-10-7545-2_16 -
Current Pharmaceutical Design 2019Melatonin, an indoleamine secreted mainly by the pineal gland, is known to modulate a wide range of circadian functions. However, this neurohormone is also synthesized... (Review)
Review
Melatonin, an indoleamine secreted mainly by the pineal gland, is known to modulate a wide range of circadian functions. However, this neurohormone is also synthesized within the eye and acts directly on ocular structures to mediate a variety of physiological processes. This review is focused on the role and therapeutic potential of melatonin in ocular diseases. We summarize data indicating that melatonin may represent a powerful tool to counteract ocular dysfunctions such as uveitis, glaucoma, age-related macular degeneration, and diabetic retinopathy. A search strategy was conducted to identify studies in PubMed (January 1990 to September 2017). In particular, we included experimental studies, clinical trials, and reviews to provide suitable insights and elucidations regarding the action of melatonin on age-related ocular disorders. Literature data suggest that melatonin could potentially protect ocular tissues by decreasing the production of free radicals and pro-inflammatory mediators. Additionally, melatonin appears to be safe and well-tolerated, even at high doses, and no adverse/side effects were reported. Although this topic remains under intense investigation, we can conclude that melatonin, as a single agent or in combination with other drugs, is an attractive pharmacological candidate for age-related ocular diseases.
Topics: Aging; Eye; Free Radicals; Glaucoma; Humans; Melatonin; Uveitis
PubMed: 31724508
DOI: 10.2174/1381612825666191113110225 -
The Journal of Experimental Biology Nov 2023Motion plays an essential role in sensory acquisition. From changing the position in which information can be acquired to fine-scale probing and active sensing, animals...
Motion plays an essential role in sensory acquisition. From changing the position in which information can be acquired to fine-scale probing and active sensing, animals actively control the way they interact with the environment. In olfaction, movement impacts the time and location of odour sampling as well as the flow of odour molecules around the olfactory organs. Employing a detailed spatiotemporal analysis, we investigated how insect antennae interact with the olfactory environment in a species with a well-studied olfactory system - the American cockroach. Cockroaches were tested in a wind-tunnel setup during the presentation of odours with different attractivity levels: colony extract, butanol and linalool. Our analysis revealed significant changes in antennal kinematics when odours were presented, including a shift towards the stream position, an increase in vertical movement and high-frequency local oscillations. Nevertheless, the antennal shifting occurred predominantly in a single antenna while the overall range covered by both antennae was maintained throughout. These findings hold true for both static and moving stimuli and were more pronounced for attractive odours. Furthermore, we found that upon odour encounter, there was an increase in the occurrence of high-frequency antennal sweeps and vertical strokes, which were shown to impact the olfactory environment's statistics directly. Our study lays out a tractable system for exploring the tight coupling between sensing and movement, in which antennal sweeps, in parallel to mammalian sniffing, are actively involved in facilitating odour capture and transport, generating odour intermittency in environments with low air movement where cockroaches dwell.
Topics: Animals; Smell; Periplaneta; Odorants; Cockroaches; Sense Organs; Arthropod Antennae; Mammals
PubMed: 37750327
DOI: 10.1242/jeb.245337 -
Trends in Biotechnology Jul 2023The sense of touch events, achieved by artificial tactile sensory systems (ATSSs), is a milestone in the progress of human-machine interactions. However, it has been a... (Review)
Review
The sense of touch events, achieved by artificial tactile sensory systems (ATSSs), is a milestone in the progress of human-machine interactions. However, it has been a challenge for ATSSs to serve functions comparable with the human tactile perception system (HTPS). The biomimetic strategies and technologies inspired by HTPS are considered an optimal solution to this challenge. Recent studies have reported bioinspired strategies for improving specific aspects of ATSS performance, such as feature collection, signal conversion, and information computation. Here, we present a systematic interpretation of biomechanisms for HTPSs, and correspondingly, address biomimetic strategies and technologies contributing to ATSSs as an integral system. This review will benefit the development and application of ATSSs in the future.
Topics: Humans; Touch; Biomimetics; Sense Organs
PubMed: 36658007
DOI: 10.1016/j.tibtech.2022.12.012 -
Developmental Dynamics : An Official... Jan 2023Sensory neurons of the head are the ones that transmit the information about the external world to our brain for its processing. Axons from cranial sensory neurons sense... (Review)
Review
Sensory neurons of the head are the ones that transmit the information about the external world to our brain for its processing. Axons from cranial sensory neurons sense different chemoattractant and chemorepulsive molecules during the journey and in the target tissue to establish the precise innervation with brain neurons and/or receptor cells. Here, we aim to unify and summarize the available information regarding molecular mechanisms guiding the different afferent sensory axons of the head. By putting the information together, we find the use of similar guidance cues in different sensory systems but in distinct combinations. In vertebrates, the number of genes in each family of guidance cues has suffered a great expansion in the genome, providing redundancy, and robustness. We also discuss recently published data involving the role of glia and mechanical forces in shaping the axon paths. Finally, we highlight the remaining questions to be addressed in the field.
Topics: Animals; Axon Guidance; Axons; Sensory Receptor Cells; Neuroglia; Sense Organs
PubMed: 35972036
DOI: 10.1002/dvdy.523 -
Acta Otorhinolaryngologica Italica :... Apr 2022
Topics: COVID-19; Humans; Nose; Otolaryngology; Pharynx; SARS-CoV-2
PubMed: 35763275
DOI: 10.14639/0392-100X-suppl.1-42-2022-06 -
Slit sense organ distribution on the legs of two species of orb-weaving spider (Araneae: Araneidae).Arthropod Structure & Development Mar 2022Biotic and abiotic mechanical stimuli are ubiquitous in the environment, and are a widely used source of sensory information in arthropods. Spiders sense mechanical...
Biotic and abiotic mechanical stimuli are ubiquitous in the environment, and are a widely used source of sensory information in arthropods. Spiders sense mechanical stimuli using hundreds of slit sense organs (small isolated slits, large isolated slits, groups of slits and lyriform organs) distributed across their bodies and appendages. These slit sense organs are embedded in the exoskeleton and detect cuticular strain. Therefore, the spatial pattern of these sensors can give clues into how mechanical stimuli from different sources might be processed and filtered as they are transmitted through the body. Here, we map the distribution of slit sense organs on the legs in two species of orb-weaving spider, A. diadematus and T. edulis, in which slit sense organ distribution has not previously been investigated. We image the spiders' legs using scanning electron microscopy, and trace the position and orientation of slits on these images to describe the distribution and external morphology of the slit sense organs. We show that both species have a similar distribution of slit sense organs, with small isolated slits occurring in consistent lines parallel to the long axis of the legs, whilst large isolated slits, groups of slits and lyriform organs appear in fixed positions near the leg joints. Our findings support what has been described in the literature for several other species of spider, which indicates that slit organ arrangement is conserved across spiders in different evolutionary lineages and with disparate hunting strategies. The dispersed distribution of small isolated slits along the whole length of the leg may be used to detect large-scale strain of the leg segment as a result of muscle activity or internal changes in haemolymph pressure.
Topics: Animals; Extremities; Microscopy, Electron, Scanning; Sense Organs; Spiders
PubMed: 35137691
DOI: 10.1016/j.asd.2022.101140 -
Cytoskeleton (Hoboken, N.J.) Oct 2020The apical organ of ctenophores is the center of sensory information that controls locomotion. Previous studies have described several types of cilia in this organ....
The apical organ of ctenophores is the center of sensory information that controls locomotion. Previous studies have described several types of cilia in this organ. However, detailed ciliary structures, particularly axonemal structures, have not been extensively investigated. Here, we reported that the apical organ of the ctenophore Bolinopsis mikado contains six types of cilia with different axonemal structures. These include the typical "9 + 2" motile axonemes, with both outer and inner dynein arms, only the inner dynein arm, or no dynein arm; axonemes with electron-dense structures in the A-tubules; "9 + 0" axonemes lacking the central pair of microtubules; and axonemes with compartmenting lamellae. Considering that "9 + 2" axonemal structures with both dynein arms are thought to be ancestral forms of cilia, the apical organ of ctenophores would comprise an elaborate assembly of modified ciliary forms that sense and transmit extracellular stimuli and generate various fluid flows.
Topics: Animals; Cilia; Ctenophora; Sense Organs
PubMed: 33103333
DOI: 10.1002/cm.21640 -
The Journal of International Advanced... May 2021Self-Contained Underwater Breathing Apparatus (SCUBA) diving is a popular sport. However, improper diving may injure different organs. The majority of dive-related... (Review)
Review
Self-Contained Underwater Breathing Apparatus (SCUBA) diving is a popular sport. However, improper diving may injure different organs. The majority of dive-related disorders concern otolaryngology, and may include hearing loss, tinnitus, aural fullness, disequilibrium, and vertigo. Three main inner ear pathological conditions can occur underwater: inner ear barotrauma (IEB), inner ear decompression sickness (IEDS), and alternobaric vertigo (AV). IEB results from inappropriate equalization of middle ear pressure and consequent inner ear injury produced by pressure changes within the middle ear; IEDS is characterized by the formation of gas bubbles within the vessels of the inner ear during rapid ascent; AV typically develops while ascending or performing the Valsalva maneuver and can follow asymmetrical equalization of middle ear pressure transmitted via the oval and round window membranes. The clinical pictures of these pathological conditions are partly superimposable, even if they have specific peculiarities. Before starting SCUBA diving, a fit-to-dive assessment is recommended. It should include an otolaryngologic examination with audiological assessment to evaluate nasal, middle ear, and tubal patency and to minimize the risk of IEB, IEDS, and AV. It is of utmost importance to identify individual risk factors and predisposing pathological conditions that favor inner ear injury before diving, to prevent acute events and preserve auditory and vestibular functions in SCUBA divers. This review aims to provide an overview of the pathological conditions characterized by inner ear injury in SCUBA divers, discussing their pathogenetic mechanisms, diagnostic work-up, and prevention.
Topics: Barotrauma; Diving; Ear, Inner; Ear, Middle; Humans; Vertigo
PubMed: 34100753
DOI: 10.5152/iao.2021.8892