scholarly journals Selective vulnerability of different types of commissural neurons for amyloid  -protein-induced neurodegeneration in APP23 mice correlates with dendritic tree morphology

Brain ◽  
2006 ◽  
Vol 129 (11) ◽  
pp. 2992-3005 ◽  
Author(s):  
E. Capetillo-Zarate ◽  
M. Staufenbiel ◽  
D. Abramowski ◽  
C. Haass ◽  
A. Escher ◽  
...  
Keyword(s):  
Dendritic Tree ◽  
Selective Vulnerability ◽  
Amyloid Protein ◽  
Commissural Neurons ◽  
Tree Morphology ◽  
Different Types

Selective vulnerability and dominant language transfer in the acquisition of the Chinese cleft construction by heritage speakers

2017 ◽  
Vol 9 (2) ◽  
pp. 202-227
Author(s):  
Ziyin Mai ◽  
Xiangjun Deng
Keyword(s):  
Second Language ◽  
Language Learners ◽  
Word Order ◽  
Second Language Learners ◽  
Native Speakers ◽  
Selective Vulnerability ◽  
Language Transfer ◽  
Heritage Speakers ◽  
Dominant Language ◽  
Different Types

Abstract This study investigates effects of selective vulnerability and dominant language transfer in heritage grammar. Mandarin Chinese has a shì…de cleft construction, which, despite its superficial similarities with the it-cleft in English, is subject to additional conditions. Four experimental tasks elicited eighteen adult heritage speakers’ implicit knowledge of the word order and the temporal, telicity and discourse conditions associated with the Chinese cleft. The heritage speakers demonstrated target-like representation of the conditions. Meanwhile, their sensitivity to the telicity and discourse conditions is weaker than that of native speakers in Beijing, suggesting selective vulnerability in the heritage grammar. By comparing the heritage speakers with adult second language learners of Chinese, we concluded that the vulnerability of the heritage grammar in the discourse domain did not result from cross-linguistic influence from English. In different types of Chinese-English bilinguals, the dominant language affects the weaker language in different ways.

scholarly journals Dendrites of Neocortical Pyramidal Neurons: The Key to Understand Intellectual Disability

2021 ◽  
Author(s):  
Alberto Granato ◽  
Adalberto Merighi
Keyword(s):  
Intellectual Disability ◽  
Mental Disorders ◽  
Cognitive Deficits ◽  
Pyramidal Neurons ◽  
Dendritic Tree ◽  
Different Types ◽  
Different Parts ◽  
Neocortical Pyramidal Neurons

AbstractPyramidal neurons (PNs) are the most abundant cells of the neocortex and display a vast dendritic tree, divided into basal and apical compartments. Morphological and functional anomalies of PN dendrites are at the basis of virtually all neurological and mental disorders, including intellectual disability. Here, we provide evidence that the cognitive deficits observed in different types of intellectual disability might be sustained by different parts of the PN dendritic tree, or by a dysregulation of their interaction.

Distribution of bipolar input to midget and parasol ganglion cells in marmoset retina

2008 ◽  
Vol 25 (1) ◽  
pp. 67-76 ◽  
Author(s):  
BAHAR ERIKÖZ ◽  
PATRICIA R. JUSUF ◽  
KUMIKO A. PERCIVAL ◽  
ULRIKE GRÜNERT
Keyword(s):  
Ampa Receptor ◽  
Synaptic Input ◽  
New World ◽  
Ganglion Cells ◽  
World Monkey ◽  
Dendritic Tree ◽  
Retinal Ganglion ◽  
Response Characteristics ◽  
Different Types ◽  
Synaptic Markers

Different types of retinal ganglion cell show differences in their response properties. Here we investigated the question of whether these differences are related to the distribution of the synaptic input to the dendritic tree. We measured the distribution and density of synaptic input to the dendrites of midget and parasol ganglion cells in the retina of a New World monkey, the marmoset,Callithrix jacchus. Ganglion cells were retrogradely labeled by dye injection into parvocellular or magnocellular regions of the lateral geniculate nucleus and subsequently photo-filled. Presumed bipolar cell synapses were identified immunocytochemically using antibodies against the ribbon protein CtBP2 or the GluR4 subunit of the AMPA receptor. For all cells, colocalized immunoreactive puncta were distributed across the entire dendritic tree. The density of the presumed bipolar input to midget ganglion cells was comparable for both synaptic markers, suggesting that the AMPA receptor GluR4 subunit is expressed at all synapses between midget bipolar and midget ganglion cells. Midget ganglion cells had an average of nine colocalized immunoreactive puncta per 100 μm2dendritic surface, and parasol cells had an average of seven colocalized immunoreactive puncta per 100 μm2dendritic surface. The densities were comparable in different regions of the dendritic tree and were not influenced by the location of the cells with respect to the fovea. Our findings suggest that the differences in the response characteristics of midget and parasol cells are not due to differences in the density of synaptic input to their dendritic tree.

Monosynaptic excitatory amino acid transmission from the posterior rhombencephalic reticular nucleus to spinal neurons involved in the control of locomotion in lamprey

1989 ◽  
Vol 62 (5) ◽  
pp. 1079-1089 ◽  
Author(s):  
Y. Ohta ◽  
S. Grillner
Keyword(s):  
Amino Acid ◽  
Laser Scanning ◽  
Excitatory Amino Acid ◽  
Dendritic Tree ◽  
Chemical Component ◽  
Reticular Nucleus ◽  
Confocal Laser ◽  
Target Cells ◽  
Spinal Neurons ◽  
Different Types

1. The reticulospinal neurons in the lamprey posterior rhombencephalic reticular nucleus (PRRN) and their projections to different types of spinal neurons have been investigated by the use of simultaneous paired intracellular recordings from one pre- and one postsynaptic cell. PRRN is of particular importance for the initiation of locomotion. 2. Intracellular stimulation of single PRRN neurons produced monosynaptic excitatory postsynaptic potentials (EPSPs) in simultaneously recorded motoneurons and spinal premotor interneurons of both the excitatory and inhibitory type. Individual PRRN neurons produced EPSPs in several different types of target cells, as revealed by signal averaging. Each single PRRN neuron had extensive monosynaptic connections to approximately 73% of the motoneuronal population. Conversely, several PRRN neurons converge on individual spinal neurons. The average amplitude of the EPSPs was 0.43 +/- 0.40 (SD) mV. The EPSPs varied in time course (time to peak = 7.5 +/- 2.8 ms; duration at one-half peak amplitude = 21.9 +/- 18.1 ms). 3. The EPSPs produced by reticulospinal cells were composed of either exclusively chemical, exclusively electrical, or mixed chemical and electrical components. The electrical EPSPs remained when the ordinary physiological solution was substituted for one without Ca2+ but with Mn2+. The chemical component of the EPSPs was always depressed when a broad-spectrum excitatory amino acid (EAA) antagonist, such as kynurenic acid, was applied, suggesting that the chemical component was because of EAA transmission. The chemical EPSP could have two components, one late, suppressed by N-methyl-D-aspartate (NMDA) antagonists, and one early because of activation of kainate/quisqualate receptors. 4. Three-dimensional reconstructions of Lucifer yellow-filled PRRN neurons were performed with a confocal laser scanning microscope. PRRN neurons producing monosynaptic excitatory amino acid EPSPs were found to have a fusiform cell body located near the surface of the fourth ventricle and an extensive fanlike dendritic tree extending to the ventral and lateral margin of the brain stem within the basal plate. The axons descend in the lateral funiculi of the spinal cord. 5. PRRN neurons utilizing EAA transmission are active during fictive locomotion. They presumably initiate and reinforce ongoing spinal locomotor activity by monosynaptically increasing the general excitability of the spinal premotor interneurons of the spinal locomotor networks by means of their extensive divergent and convergent monosynaptic connections.

Unique Amyloid Protein Subunit common to Different Types of Amyloid Fibril

Nature ◽  
1973 ◽  
Vol 244 (5415) ◽  
pp. 362-364 ◽  
Author(s):  
G. HUSBY ◽  
J. B. NATVIG ◽  
T. E. MICHAELSEN ◽  
K. SLETTEN ◽  
H. HÖST
Keyword(s):  
Amyloid Fibril ◽  
Amyloid Protein ◽  
Protein Subunit ◽  
Different Types

scholarly journals Dendrites of Neocortical Pyramidal Neurons: The Key to Understand Intellectual Disability

2021 ◽  
Author(s):  
Alberto Granato ◽  
Adalberto Merighi
Keyword(s):  
Intellectual Disability ◽  
Mental Disorders ◽  
Cognitive Deficits ◽  
Pyramidal Neurons ◽  
Dendritic Tree ◽  
Different Types ◽  
Different Parts ◽  
Neocortical Pyramidal Neurons

Abstract Pyramidal neurons (PNs) are the most abundant cells of the neocortex and display a vast dendritic tree, divided into basal and apical compartments. Morphological and functional anomalies of PN dendrites are at the basis of virtually all neurological and mental disorders, including intellectual disability. Here we provide evidence that the cognitive deficits observed in different types of intellectual disability might be sustained by different parts of the PN dendritic tree, or by a dysregulation of their interaction.

The extinction time of a general birth and death process with catastrophes

1986 ◽  
Vol 23 (04) ◽  
pp. 851-858 ◽  
Author(s):  
P. J. Brockwell
Keyword(s):  
Laplace Transform ◽  
Size Distribution ◽  
Sufficient Conditions ◽  
Necessary And Sufficient Conditions ◽  
Death Process ◽  
Extinction Time ◽  
Birth And Death Process ◽  
Different Types ◽  
The Laplace Transform ◽  
Necessary And Sufficient

The Laplace transform of the extinction time is determined for a general birth and death process with arbitrary catastrophe rate and catastrophe size distribution. It is assumed only that the birth rates satisfyλ0= 0,λj> 0 for eachj> 0, and. Necessary and sufficient conditions for certain extinction of the population are derived. The results are applied to the linear birth and death process (λj=jλ, µj=jμ) with catastrophes of several different types.

Differentiating between different forms of moral obligations

2020 ◽  
Vol 43 ◽  
Author(s):  
Rajen A. Anderson ◽  
Benjamin C. Ruisch ◽  
David A. Pizarro
Keyword(s):  
Moral Character ◽  
Moral Obligations ◽  
Different Types

Abstract We argue that Tomasello's account overlooks important psychological distinctions between how humans judge different types of moral obligations, such as prescriptive obligations (i.e., what one should do) and proscriptive obligations (i.e., what one should not do). Specifically, evaluating these different types of obligations rests on different psychological inputs and has distinct downstream consequences for judgments of moral character.

Ultrastructural Investigations of the Contractile Filaments of Amoebae

1974 ◽  
Vol 32 ◽  
pp. 188-189
Author(s):  
P.L. Moore
Keyword(s):  
Cytoplasmic Streaming ◽  
Three Dimensional ◽  
Freeze Fracture ◽  
Amoeboid Movement ◽  
Different Types ◽  
Chemical Conditions ◽  
Complete Interpretation

Previous freeze fracture results on the intact giant, amoeba Chaos carolinensis indicated the presence of a fibrillar arrangement of filaments within the cytoplasm. A complete interpretation of the three dimensional ultrastructure of these structures, and their possible role in amoeboid movement was not possible, since comparable results could not be obtained with conventional fixation of intact amoebae. Progress in interpreting the freeze fracture images of amoebae required a more thorough understanding of the different types of filaments present in amoebae, and of the ways in which they could be organized while remaining functional.The recent development of a calcium sensitive, demembranated, amoeboid model of Chaos carolinensis has made it possible to achieve a better understanding of such functional arrangements of amoeboid filaments. In these models the motility of demembranated cytoplasm can be controlled in vitro, and the chemical conditions necessary for contractility, and cytoplasmic streaming can be investigated. It is clear from these studies that “fibrils” exist in amoeboid models, and that they are capable of contracting along their length under conditions similar to those which cause contraction in vertebrate muscles.

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