Quantitative Three-Dimensional Reconstructions of Excitatory Synaptic Boutons in Layer 5 of the Adult Human Temporal Lobe Neocortex: A Fine-Scale Electron Microscopic Analysis

2018 ◽  
Vol 29 (7) ◽  
pp. 2797-2814 ◽  
Author(s):  
Rachida Yakoubi ◽  
Astrid Rollenhagen ◽  
Marec von Lehe ◽  
Yachao Shao ◽  
Kurt Sätzler ◽  
...  
Keyword(s):  
Temporal Lobe ◽  
Three Dimensional ◽  
Microscopic Analysis ◽  
Synaptic Cleft ◽  
Brain Regions ◽  
Fine Scale ◽  
Electron Microscopic ◽  
Readily Releasable Pool ◽  
Synaptic Boutons ◽  
Human Temporal Lobe

Abstract Studies of synapses are available for different brain regions of several animal species including non-human primates, but comparatively little is known about their quantitative morphology in humans. Here, synaptic boutons in Layer 5 (L5) of the human temporal lobe (TL) neocortex were investigated in biopsy tissue, using fine-scale electron microscopy, and quantitative three-dimensional reconstructions. The size and organization of the presynaptic active zones (PreAZs), postsynaptic densities (PSDs), and that of the 3 distinct pools of synaptic vesicles (SVs) were particularly analyzed. L5 synaptic boutons were medium-sized (~6 μm2) with a single but relatively large PreAZ (~0.3 μm2). They contained a total of ~1500 SVs/bouton, ~20 constituting the putative readily releasable pool (RRP), ~180 the recycling pool (RP), and the remainder, the resting pool. The PreAZs, PSDs, and vesicle pools are ~3-fold larger than those of CNS synapses in other species. Astrocytic processes reached the synaptic cleft and may regulate the glutamate concentration. Profound differences exist between synapses in human TL neocortex and those described in various species, particularly in the size and geometry of PreAZs and PSDs, the large RRP/RP, and the astrocytic ensheathment suggesting high synaptic efficacy, strength, and modulation of synaptic transmission at human synapses.

Quantitative Three-Dimensional Reconstructions of Excitatory Synaptic Boutons in the “Barrel Field” of the Adult “Reeler” Mouse Somatosensory Neocortex: A Comparative Fine-Scale Electron Microscopic Analysis with the Wild Type Mouse

2019 ◽  
Vol 30 (5) ◽  
pp. 3209-3227
Author(s):  
Miriam Prume ◽  
Astrid Rollenhagen ◽  
Rachida Yakoubi ◽  
Kurt Sätzler ◽  
Joachim Hr Lübke
Keyword(s):  
Structural Parameters ◽  
Three Dimensional ◽  
Wild Type Mouse ◽  
Fine Scale ◽  
Synaptic Organization ◽  
Wild Type ◽  
Structural Determinants ◽  
Electron Microscopic ◽  
Synaptic Boutons ◽  
Active Zones

Abstract Synapses are key structural determinants for information processing and computations in the normal and pathologically altered brain. Here, the quantitative morphology of excitatory synaptic boutons in the “reeler” mutant, a model system for various neurological disorders, was investigated and compared with wild-type (WT) mice using high-resolution, fine-scale electron microscopy (EM) and quantitative three-dimensional (3D) models of synaptic boutons. Beside their overall geometry, the shape and size of presynaptic active zones (PreAZs) and postsynaptic densities (PSDs) forming the active zones and the three pools of synaptic vesicles (SVs), namely the readily releasable pool (RRP), the recycling pool (RP), and the resting pool, were quantified. Although the reeler mouse neocortex is severely disturbed, no significant differences were found in most of the structural parameters investigated: the size of boutons (~3 μm2), size of the PreAZs and PSDs (~0.17 μm2), total number of SVs, and SVs within a perimeter (p) of 10 nm and p20 nm RRP; the p60 nm, p100 nm, and p60–p200 nm RP; and the resting pool, except the synaptic cleft width. Taken together, the synaptic organization and structural composition of synaptic boutons in the reeler neocortex remain comparably “normal” and may thus contribute to a “correct” wiring of neurons within the reeler cortical network.

scholarly journals Cubic membranes: a structure-based design for DNA uptake

2008 ◽  
Vol 5 (26) ◽  
pp. 1023-1029 ◽  
Author(s):  
Zakaria Almsherqi ◽  
Stephen Hyde ◽  
Malarmathy Ramachandran ◽  
Yuru Deng
Keyword(s):  
Mammalian Cells ◽  
Gene Transfection ◽  
Three Dimensional ◽  
Microscopic Analysis ◽  
Cell Types ◽  
Dna Uptake ◽  
Cell Organelles ◽  
Electron Microscopic ◽  
Culture Cells ◽  
Cubic Membrane

Cubic membranes are soft three-dimensional crystals found within cell organelles in a variety of living systems, despite the aphorism of Fedorov: ‘crystallization is death’. They consist of multi-bilayer lipid–protein stacks, folded onto anticlastic surfaces that resemble triply periodic minimal surfaces, forming highly swollen crystalline sponges. Although cubic membranes have been observed in numerous cell types and under different pathophysiological conditions, knowledge about the formation and potential function(s) of non-lamellar, cubic structures in biological systems is scarce. We report that mitochondria with this cubic membrane organization isolated from starved amoeba Chaos carolinense interact sufficiently with short segments of phosphorothioate oligonucleotides (PS-ODNs) to give significant ODNs uptake. ODNs condensed within the convoluted channels of cubic membrane by an unknown passive targeting mechanism. Moreover, the interaction between ODNs and cubic membrane is sufficient to retard electrophoretic mobility of the ODN component in the gel matrix. These ODN–cubic membrane complexes are readily internalized within the cytoplasm of cultured mammalian cells. Transmission electron microscopic analysis confirms ODNs uptake by cubic membranes and internalization of ODN–cubic membrane complexes into the culture cells. Cubic membranes thus may offer a new, potentially benign medium for gene transfection.

scholarly journals The xograph®: an investigation of parallax panoramagrams and earlier autostereoscopic methods

2021 ◽  
Author(s):  
Vanessa Dumais
Keyword(s):  
Mass Media ◽  
Physical Properties ◽  
Production Process ◽  
Three Dimensional ◽  
Microscopic Analysis ◽  
Detailed Account ◽  
Electron Microscopic ◽  
History Of ◽  
1960S And 1970S ◽  
The 1960S

Introduced by Cowles Communications and Visual Panographics in 1964, the xograph® or parallax panoramagram, was the first lenticular, autostereoscopic, photomechanical object created for the mass media. Publications such as LOOK magazine and Venture: A Traveler’s Guide frequently distributed xographs® during the 1960s and 1970s, after which time, the xograph® began to disappear from mass publications. The thesis provides a detailed account of the history of three-dimensional photographic techniques and places the xograph® within this history. It addresses the contributions and collaboration of Arthur Rothstein, Marvin Whatmore, Visual Panographics and Cowles Communications in the creation, production and dissemination of xographs®. The thesis then describes xograph® production process and the results of an electron microscopic analysis of an xograph® made to determine its physical properties . The conclusion offers suggestions for preservation guidelines for these fascinating objects.

Development of PLA-HAp-CS-based biocompatible functional prototype: A case study

2018 ◽  
Vol 33 (3) ◽  
pp. 305-323 ◽  
Author(s):  
Nishant Ranjan ◽  
Rupinder Singh ◽  
IPS Ahuja
Keyword(s):  
3D Printing ◽  
Three Dimensional ◽  
Microscopic Analysis ◽  
Fused Deposition Modelling ◽  
Electron Microscopic ◽  
Dead Weight ◽  
Fused Deposition ◽  
Twin Screw ◽  
Functional Prototype

In this article, detailed procedure for the development of polylactic acid (PLA), hydroxyapatite (HAp) and chitosan (CS)-based biocompatible functional prototype has been outlined by using three-dimensional (3D) printing as a case study. The biocompatible composite-based feedstock filament (comprising of PLA-HAp-CS) has been prepared through twin-screw extruder (TSE) for open-source fused deposition modelling (FDM)-based 3D printer. This case study provides two-stage multifactor optimization: (a) for preparation of feedstock filament on TSE and (b) 3D printing on FDM based upon tensile and flexural samples. The results of study suggest that the best settings of input parameters for TSE are barrel temperature of 190°C, screw speed of 140 r/min and dead weight of 12 kg. Further, the optimized settings for FDM are layer thickness of 0.2 mm, deposition angle of 30/45° and infill density of 100%. The results have been supported by scanning electron microscopic analysis.

scholarly journals Ultrastructural heterogeneity of layer 4 excitatory synaptic boutons in the adult human temporal lobe neocortex

eLife ◽  
2019 ◽  
Vol 8 ◽  
Author(s):  
Rachida Yakoubi ◽  
Astrid Rollenhagen ◽  
Marec von Lehe ◽  
Dorothea Miller ◽  
Bernd Walkenfort ◽  
...  
Keyword(s):  
Temporal Lobe ◽  
Synaptic Vesicles ◽  
Building Blocks ◽  
Synaptic Activity ◽  
Quantitative Morphology ◽  
Layer 4 ◽  
Total Pool ◽  
Synaptic Boutons ◽  
Computational Properties ◽  
Human Temporal Lobe

Synapses are fundamental building blocks controlling and modulating the ‘behavior’ of brain networks. How their structural composition, most notably their quantitative morphology underlie their computational properties remains rather unclear, particularly in humans. Here, excitatory synaptic boutons (SBs) in layer 4 (L4) of the temporal lobe neocortex (TLN) were quantitatively investigated. Biopsies from epilepsy surgery were used for fine-scale and tomographic electron microscopy (EM) to generate 3D-reconstructions of SBs. Particularly, the size of active zones (AZs) and that of the three functionally defined pools of synaptic vesicles (SVs) were quantified. SBs were comparatively small (~2.50 μm2), with a single AZ (~0.13 µm2); preferentially established on spines. SBs had a total pool of ~1800 SVs with strikingly large readily releasable (~20), recycling (~80) and resting pools (~850). Thus, human L4 SBs may act as ‘amplifiers’ of signals from the sensory periphery, integrate, synchronize and modulate intra- and extracortical synaptic activity.

scholarly journals The xograph®: an investigation of parallax panoramagrams and earlier autostereoscopic methods

2021 ◽  
Author(s):  
Vanessa Dumais
Keyword(s):  
Mass Media ◽  
Physical Properties ◽  
Production Process ◽  
Three Dimensional ◽  
Microscopic Analysis ◽  
Detailed Account ◽  
Electron Microscopic ◽  
History Of ◽  
1960S And 1970S ◽  
The 1960S

Introduced by Cowles Communications and Visual Panographics in 1964, the xograph® or parallax panoramagram, was the first lenticular, autostereoscopic, photomechanical object created for the mass media. Publications such as LOOK magazine and Venture: A Traveler’s Guide frequently distributed xographs® during the 1960s and 1970s, after which time, the xograph® began to disappear from mass publications. The thesis provides a detailed account of the history of three-dimensional photographic techniques and places the xograph® within this history. It addresses the contributions and collaboration of Arthur Rothstein, Marvin Whatmore, Visual Panographics and Cowles Communications in the creation, production and dissemination of xographs®. The thesis then describes xograph® production process and the results of an electron microscopic analysis of an xograph® made to determine its physical properties . The conclusion offers suggestions for preservation guidelines for these fascinating objects.

scholarly journals Viroplasm matrix protein Pns9 from rice gall dwarf virus forms an octameric cylindrical structure

2011 ◽  
Vol 92 (9) ◽  
pp. 2214-2221 ◽  
Author(s):  
Fusamichi Akita ◽  
Naoyuki Miyazaki ◽  
Hiroyuki Hibino ◽  
Takumi Shimizu ◽  
Akifumi Higashiura ◽  
...  
Keyword(s):  
Electron Microscope ◽  
Matrix Protein ◽  
Three Dimensional ◽  
Microscopic Analysis ◽  
Host Cells ◽  
Size Exclusion ◽  
Dwarf Virus ◽  
Electron Microscopic ◽  
The Family ◽  
Rice Gall Dwarf Virus

The non-structural Pns9 protein of rice gall dwarf virus (RGDV) accumulates in viroplasm inclusions, which are structures that appear to play an important role in viral morphogenesis and are commonly found in host cells infected by viruses in the family Reoviridae. Immunofluorescence and immunoelectron microscopy of RGDV-infected vector cells in monolayers, using antibodies against Pns9 of RGDV and expression of Pns9 in Spodoptera frugiperda cells, demonstrated that Pns9 is the minimal viral factor necessary for formation of viroplasm inclusion during infection by RGDV. When Pns9 in solution was observed under a conventional electron microscope, it appeared as ring-like aggregates of approximately 100 Å in diameter. Cryo-electron microscopic analysis of these aggregates revealed cylinders of octameric Pns9, whose dimensions were similar to those observed under the conventional electron microscope. Octamerization of Pns9 in solution was confirmed by the results of size-exclusion chromatography. Among proteins of viruses that belong to the family Reoviridae whose three-dimensional structures are available, a matrix protein of the viroplasm of rotavirus, NSP2, forms similar octamers, an observation that suggests similar roles for Pns9 and NSP2 in morphogenesis in animal-infecting and in plant-infecting reoviruses.

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