A Developmental Study of the Cerebellar Nucleus in the Catshark, a Basal Gnathostome

2017 ◽  
Vol 89 (1) ◽  
pp. 1-14 ◽  
Author(s):  
Sol Pose-Méndez ◽  
Isabel Rodríguez-Moldes ◽  
Eva Candal ◽  
Sylvie Mazan ◽  
Ramón Anadón
Keyword(s):  
Ventricular Zone ◽  
Cerebellar Nuclei ◽  
Cerebellar Nucleus ◽  
Developmental Expression ◽  
Developmental Study ◽  
Evolutionary Innovation ◽  
Evolution And Development ◽  
Rhombic Lip ◽  
Different Sources ◽  
Insight Into

The output of the cerebellar cortex is mainly released via cerebellar nuclei which vary in number and complexity among gnathostomes, extant vertebrates with a cerebellum. Cartilaginous fishes, a basal gnathostome lineage, show a conspicuous, well-organized cerebellar nucleus, unlike ray-finned fishes. To gain insight into the evolution and development of the cerebellar nucleus, we analyzed in the shark Scyliorhinus canicula (a chondrichthyan model species) the developmental expression of several genes coding for transcription factors (ScLhx5,ScLhx9,ScTbr1, and ScEn2) and the distribution of the protein calbindin, since all appear to be involved in cerebellar nuclei patterning in other gnathostomes. Three regions (subventricular, medial or central, and lateral or superficial) became recognizable in the cerebellar nucleus of this shark during development. Present genoarchitectonic and neurochemical data in embryos provide insight into the origin of the cerebellar nucleus in chondrichthyans and support a tripartite mediolateral organization of the cerebellar nucleus, as previously described in adult sharks. Furthermore, the expression pattern of ScLhx5,ScLhx9, and ScTbr1 in this shark, together with that of markers of proliferation, migration, and early differentiation of neurons, is compatible with the hypothesis that, as in mammals, different subsets of cerebellar nucleus neurons are originated from progenitors of 2 different sources: the ventricular zone of the cerebellar plate and the rhombic lip. We also present suggestive evidence that Lhx9 expression is involved in cerebellar nuclei patterning early on in gnathostome evolution, rather than representing an evolutionary innovation of the dentate nucleus in mammals, as previously hypothesized.

scholarly journals Early Subset of Cerebellar Nuclei Neurons Derived from Mesencephalon in Mice

2017 ◽  
Author(s):  
Maryam Rahimi-Balaei ◽  
Xiaodan Jiao ◽  
Fiona E. Parkinson ◽  
Behzad Yeganeh ◽  
Hassan Marzban
Keyword(s):  
Neural Crest ◽  
Purkinje Cells ◽  
Ventricular Zone ◽  
Cerebellar Nuclei ◽  
Nerve Fibers ◽  
Neurotrophin Receptor ◽  
Cerebellar Development ◽  
Developing Cerebellum ◽  
Rhombic Lip ◽  
Migratory Pathway

ABSTRACTDuring cerebellar development, cerebellar nuclei (CN) neurons and Purkinje cells are the earliest born among the different neuronal subtypes. Purkinje cells are the sole output of the cerebellar cortex and project to the CN. The CN represents the main output of the cerebellum, which is generated from the rhombic lip and the ventricular zone. We used immunohistochemistry, embryonic cultures, dye tracers and in situ hybridization to examine the origin of a new subset of CN neurons from the mesencephalon during early cerebellar development. Our results show that a subset of CN neurons, which are immunopositive for α-synuclein (SNCA) and Otx2, originate from the mesencephalon and cross the isthmus toward the rostral end of the nuclear transitory zone. Double immunostaining of the SNCA with Otx2 or p75 neurotrophin receptor (p75ntr) indicates that these cells are derived from neural crest cells. We also showed that this population of neurons with nerve fibers terminates at the subpial surface of putative lobules VI/VII. The SNCA+/Otx2+/p75+ cells, which divide the cerebellar primordium into rosterodorsal and caudoventral compartments, show increased cleaved caspase-3 activation, which suggests temporary presence of these cells due to apoptosis. These results strongly suggest that early CN neurons originate from the mesencephalic neural crest population and cross the isthmus to contribute as a subset of the CN. Their temporary presence in the nuclear transitory zone suggests that these neurons/fibers play a regulatory role as a signaling center to attract early afferent pioneer axons and provide neuronal migratory pathway during early cerebellar development.Significance StatementDuring cerebellar development two germinal zones are involved in cerebellar neurogenesis: the rhombic lip and the ventricular zone, which are located in the developing cerebellum itself. Our findings indicate that a subset of cerebellar nuclei neurons have an external origin, the mesencephalon, and they are the earliest born neurons that enter to the developing cerebellum. In this study, we focused on the origin of these cells and traced their migratory pathway from the mesencephalon while crossing the isthmus, followed them when they entered to the developing cerebellum. We also demonstrated their potential role on later born cells during cerebellar development.

scholarly journals An infant burial from Arma Veirana in northwestern Italy provides insights into funerary practices and female personhood in early Mesolithic Europe

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jamie Hodgkins ◽  
Caley M. Orr ◽  
Claudine Gravel-Miguel ◽  
Julien Riel-Salvatore ◽  
Christopher E. Miller ◽  
...  
Keyword(s):  
Young Infant ◽  
Ice Age ◽  
Mortuary Practices ◽  
Cultural Significance ◽  
Biological Profile ◽  
Evolution And Development ◽  
Last Ice Age ◽  
Gender Based ◽  
Funerary Treatment ◽  
Insight Into

AbstractThe evolution and development of human mortuary behaviors is of enormous cultural significance. Here we report a richly-decorated young infant burial (AVH-1) from Arma Veirana (Liguria, northwestern Italy) that is directly dated to 10,211–9910 cal BP (95.4% probability), placing it within the early Holocene and therefore attributable to the early Mesolithic, a cultural period from which well-documented burials are exceedingly rare. Virtual dental histology, proteomics, and aDNA indicate that the infant was a 40–50 days old female. Associated artifacts indicate significant material and emotional investment in the child’s interment. The detailed biological profile of AVH-1 establishes the child as the earliest European near-neonate documented to be female. The Arma Veirana burial thus provides insight into sex/gender-based social status, funerary treatment, and the attribution of personhood to the youngest individuals among prehistoric hunter-gatherer groups and adds substantially to the scant data on mortuary practices from an important period in prehistory shortly following the end of the last Ice Age.

scholarly journals Genetic deletion of genes in the cerebellar rhombic lip lineage can stimulate compensation through adaptive reprogramming of ventricular zone-derived progenitors

2019 ◽  
Vol 14 (1) ◽  
Author(s):  
Alexandre Wojcinski ◽  
Morgane Morabito ◽  
Andrew K. Lawton ◽  
Daniel N. Stephen ◽  
Alexandra L. Joyner
Keyword(s):  
Ventricular Zone ◽  
Genetic Deletion ◽  
Rhombic Lip

Effects of red nucleus inactivation on burst discharge in turtle cerebellum in vitro: evidence for positive feedback

1996 ◽  
Vol 76 (4) ◽  
pp. 2200-2210 ◽  
Author(s):  
J. Keifer
Keyword(s):  
Cerebellar Cortex ◽  
Positive Feedback ◽  
Red Nucleus ◽  
Cerebellar Nuclei ◽  
Cerebellar Nucleus ◽  
Normal Brain ◽  
Deep Cerebellar Nuclei ◽  
Burst Discharge ◽  
Sustained Discharge

1. In behaving animals the red nucleus produces sustained action potential discharge during movements of the limbs. These bursts are thought to encode parameters of movement and thereby represent motor commands. Similar bursts can be recorded in the in vitro brain stem-cerebellum from the turtle. In this preparation, sustained discharge of red nucleus neurons was postulated to be generated by N-methyl-D-aspartate-mediated cellular mechanisms acting in combination with positive feedback in a recurrent cerebellorubral network. The present study was designed to test this positive feedback hypothesis. During recording of sustained discharge in the deep cerebellar nuclei and cortex, the red nucleus was reversibly inactivated by microinjection. The positive feedback hypothesis would be supported if activity in the cerebellum was attenuated by inactivation of the red nucleus. A nonrecurrent source of excitation would have to be postulated if cerebellar activity was unaffected. 2. Extracellular single-unit recordings were made from neurons in the deep cerebellar nuclei, cerebellar cortex, and vestibular nuclei. Burst discharges were evoked by brief electrical stimuli applied to the spinal cord that activated sensory structures. During inactivation of the red nucleus, sensory projections to the cerebellum that may evoke burst discharge were unaffected. Pressure microinjections of cobalt, lidocaine, gamma-aminobutyric acid (GABA), or 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) were used to reversibly inactivate the red nucleus. Saline injections were also tested. 3. Sustained discharge of all neurons recorded in the lateral cerebellar nucleus was greatly attenuated or blocked completely by injection of the pharmacological agents into the red nucleus. These effects were reversible. Of the recordings in the cerebellar cortex, 63% of these were blocked. All four compounds tested were effective blockers of the bursts, although the effects of GABA were less potent than the others. Saline injections into the red nucleus showed no effect. Burst discharges of single units recorded in either the medial cerebellar nucleus or the vestibular complex, which do not receive input from the red nucleus, showed no effect of red nucleus inactivation. 4. The results showed that sustained discharge in the cerebellum was significantly attenuated by inactivation of the red nucleus even though sensory input that may trigger the bursts was intact. These data support the hypothesis that sustained discharge in the cerebellorubral circuit is generated by a distributed neuronal network that uses positive feedback. The results have implications for mechanisms underlying normal brain function and some motor disorders.

Von den Grenzen einer frühneuzeitlichen Biographie: Melchior Adams Vita Helii Eobani Hessi und ihre Quellen

Daphnis ◽  
2018 ◽  
Vol 46 (3) ◽  
pp. 345-426
Author(s):  
Klaus-Dieter Beims
Keyword(s):  
Intellectual History ◽  
German Speaking ◽  
History Of ◽  
Cultural World ◽  
Different Sources ◽  
Insight Into

Melchior Adam’s collection of biographies offers a unique insight into the intellectual history of the German-speaking cultural world from the late 15th century onwards. Using the Vita Helii Eobani Hessi as an example, this article examines the different sources available to Adam. Furthermore, the article analyses the selection and literary transformation of these sources in Adam’s biography. The image of Hessus in Adam’s main source already shows all the evidence of being just a construction; the essay examines if Adam is checking the construction in a critical manner or if he just accepts it. By comparing the sources that Adam used, the limits of the biography’s historical content are revealed.

Intentional reasoning: A developmental study of behaviorally aggressive and normal boys

1994 ◽  
Vol 6 (2) ◽  
pp. 285-304 ◽  
Author(s):  
Anne McKeough ◽  
Tim Yates ◽  
Anthony Marini
Keyword(s):  
Cognitive Complexity ◽  
Defense Mechanisms ◽  
Mental States ◽  
Developmental Study ◽  
The Social ◽  
Behaviorally Disturbed ◽  
Age Appropriate ◽  
Maladaptive Thought ◽  
Behavioral Aggression ◽  
Insight Into

AbstractThe purpose of this work was to investigate the way in which boys, ages 6, 8, and 10 years, who are behaviorally disturbed, understand motives behind human behavior, compared to normally functioning peers. Four tasks were administered that differed in surface features but that shared an underlying conceptual structure. A structural analysis of response protocols was undertaken to assess the level of cognitive complexity of their productions. Age-appropriate performance required varying degrees of intentional understanding (i.e., the reciprocal causal relations between action and mental states such as feelings and desires). The results of this analysis supported our predictions that behaviorally disturbed children use developmentally naive reasoning in the domain of conflict resolution, compared with their normal peers. Additionally, a thematic analysis of the content of responses was performed. The results of this analysis showed that the two groups' reasoning also differed qualitatively, in that the aggressive boys showed greater evidence of socially maladaptive thought, whereas the comparison group's performance was largely adaptive. We propose that early-formed primitive defense mechanisms may interfere with the aggressive group's construction of prosocial mental models of the social world. The results suggest that this line of research, which integrates developmental and psychoanalytic theory, has the potential to offer insight into the mechanisms underlying behavioral aggression.

scholarly journals Olig3 regulates early cerebellar development

eLife ◽  
2021 ◽  
Vol 10 ◽  
Author(s):  
Elijah D Lowenstein ◽  
Aleksandra Rusanova ◽  
Jonas Stelzer ◽  
Marc Hernaiz-Llorens ◽  
Adrian E Schroer ◽  
...  
Keyword(s):  
Transcription Factor ◽  
Purkinje Cell ◽  
Ventricular Zone ◽  
Cerebellar Development ◽  
Brain Functions ◽  
Key Factor ◽  
Progenitor Cell Proliferation ◽  
Molecular Machinery ◽  
Neuronal Types ◽  
Rhombic Lip

The mature cerebellum controls motor skill precision and participates in other sophisticated brain functions that include learning, cognition, and speech. Different types of GABAergic and glutamatergic cerebellar neurons originate in temporal order from two progenitor niches, the ventricular zone and rhombic lip, which express the transcription factors Ptf1a and Atoh1, respectively. However, the molecular machinery required to specify the distinct neuronal types emanating from these progenitor zones is still unclear. Here, we uncover the transcription factor Olig3 as a major determinant in generating the earliest neuronal derivatives emanating from both progenitor zones in mice. In the rhombic lip, Olig3 regulates progenitor cell proliferation. In the ventricular zone, Olig3 safeguards Purkinje cell specification by curtailing the expression of Pax2, a transcription factor that suppresses the Purkinje cell differentiation program. Our work thus defines Olig3 as a key factor in early cerebellar development.

scholarly journals A database development and analysis of selected side impact collisions in Toronto

2021 ◽  
Author(s):  
John Zaki Bou-Younes
Keyword(s):  
Traffic Accidents ◽  
Side Impact ◽  
Vehicle Speed ◽  
Software Release ◽  
Late Model ◽  
The City ◽  
Different Sources ◽  
Insight Into ◽  
Statistical Analysis Software ◽  
Selection Of

This thesis is based on the initial phase of a project that developed an in-depth collision database and performed an analysis of police reported side-impact collisions for the City of Toronto intersections between 1998 and 2000. Currently, collision data exists through several different sources in Ontario. The development of a database involving the amalgamation of collision forms, the selection of data fields, and the collection of real collision data from selected, thoroughly investigated side impact collisions involving late model vehicles (1998 and newer), is described. For analysis, Statistical Analysis Software Release 8.02 was used to investigate causation and causal factors of side impact collisions. Statistically significant collision factors determined by fault propensity included apparent driver action, driver age, front seat passenger age, maximum posted speed, approximate vehicle speed, road character, and number of lanes. For intersection collision propensity, statistically significant findings included the system used, presence of flashing signals, intersection legs, roadway volume, and intersection leg road classifications. It is anticipated that the findings from this analysis can provide insight into significant factors in side-impact collisions that will be applied with greater focus to the in-depth collision database, once developed. Traffic accidents

scholarly journals A database development and analysis of selected side impact collisions in Toronto

2021 ◽  
Author(s):  
John Zaki Bou-Younes
Keyword(s):  
Traffic Accidents ◽  
Side Impact ◽  
Vehicle Speed ◽  
Software Release ◽  
Late Model ◽  
The City ◽  
Different Sources ◽  
Insight Into ◽  
Statistical Analysis Software ◽  
Selection Of

This thesis is based on the initial phase of a project that developed an in-depth collision database and performed an analysis of police reported side-impact collisions for the City of Toronto intersections between 1998 and 2000. Currently, collision data exists through several different sources in Ontario. The development of a database involving the amalgamation of collision forms, the selection of data fields, and the collection of real collision data from selected, thoroughly investigated side impact collisions involving late model vehicles (1998 and newer), is described. For analysis, Statistical Analysis Software Release 8.02 was used to investigate causation and causal factors of side impact collisions. Statistically significant collision factors determined by fault propensity included apparent driver action, driver age, front seat passenger age, maximum posted speed, approximate vehicle speed, road character, and number of lanes. For intersection collision propensity, statistically significant findings included the system used, presence of flashing signals, intersection legs, roadway volume, and intersection leg road classifications. It is anticipated that the findings from this analysis can provide insight into significant factors in side-impact collisions that will be applied with greater focus to the in-depth collision database, once developed. Traffic accidents

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