scholarly journals The “amphi”-brains of amphipods: New insights from the neuroanatomy ofParhyale hawaiensis(Dana, 1853)

2019 ◽  
Author(s):  
Christin Wittfoth ◽  
Steffen Harzsch ◽  
Carsten Wolff ◽  
Andy Sombke
Keyword(s):  
Laser Scanning ◽  
Sensory Modality ◽  
Projection Neuron ◽  
The Body ◽  
Laser Scanning Microscopy ◽  
Central Complex ◽  
Recent Analysis ◽  
Marine Animal ◽  
Developmental Studies ◽  
The Brain

ABSTRACTBackgroundOver the last years, the amphipod crustaceanParhyale hawaiensishas developed into an attractive marine animal model for evolutionary developmental studies that offers several advantages over existing experimental organisms. It is easy to rear in laboratory conditions with embryos available year-round and amenable to numerous kinds of embryological and functional genetic manipulations. However, beyond these developmental and genetic analyses, research on the architecture of its nervous system is fragmentary. In order to provide a first neuroanatomical atlas of the brain, we investigatedP. hawaiensisusing immunohistochemical labelings combined with laser-scanning microscopy, X-ray microcomputed tomography, histological sectioning and 3D reconstructions.ResultsAs in most amphipod crustaceans, the brain is dorsally bent out of the body axis with downward oriented lateral hemispheres of the protocerebrum. It comprises almost all prominent neuropils that are part of the suggested ground pattern of malacostracan crustaceans (except the lobula plate and projection neuron tract neuropil). Beyond a general uniformity of these neuropils, the brain ofP. hawaiensisis characterized by a modified lamina (first order visual neuropil) and, compared to other Amphipoda, an elaborated central complex. The lamina displays a chambered appearance that, in the light of a recent analysis on photoreceptor projections inP. hawaiensis, corresponds to specialized photoreceptor terminals. The presence of a poorly differentiated hemiellipsoid body is indicated and critically discussed.ConclusionsAlthough amphipod brains show a general uniformity, when compared with each other, there is also a certain degree of variability in architecture and size of different neuropils. In contrast to other amphipods, the brain ofP. hawaiensisdoes not display any striking modifications or bias towards one particular sensory modality. Thus, we conclude that its brain may represent a common type of an amphipod brain.

P10.02 Combined methods of a micropump system and a chronic cranial window allows tumor observation with multi photon laser scanning microscopy under continuous treatment

2021 ◽  
Vol 23 (Supplement_2) ◽  
pp. ii28-ii28
Author(s):  
S Weil ◽  
E Jung ◽  
D Domínguez Azorín ◽  
J Higgins ◽  
J Reckless ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Tumor Cells ◽  
Blood Brain Barrier ◽  
Laser Scanning ◽  
Laser Scanning Microscopy ◽  
New Drugs ◽  
Brain Barrier ◽  
Cranial Window ◽  
Blood Brain ◽  
The Brain

Abstract BACKGROUND Glioblastomas are notoriously therapy resistant tumors. As opposed to other tumor entities, no major advances in therapeutic success have been made in the past decades. This has been calling for a deeper biological understanding of the tumor, its growth and resistance patterns. We have been using a xenograft glioma model, where human glioblastoma cells are implanted under chronic cranial windows and studied longitudinally over many weeks and months using multi photon laser scanning microscopy (MPLSM). To test the effect of (new) drugs, a stable and direct delivery system avoiding the blood-brain-barrier has come into our interest. MATERIAL AND METHODS We implanted cranial windows and fluorescently labeled human glioblastoma stem-like cells into NMRI nude mice to follow up on the tumor development in our MPLSM model. After tumor establishment, an Alzet® micropump was implanted to directly deliver agents via a catheter system continuously over 28 days directly under the cranial window onto the brain surface. Using the MPLSM technique, the continuous delivery and infusion of drugs onto the brain and into the tumor was measured over many weeks in detail using MPLSM. RESULTS The establishment of the combined methods allowed reliable concurrent drug delivery over 28 days bypassing the blood-brain-barrier. Individual regions and tumor cells could be measured and followed up before, and after the beginning of the treatment, as well as after the end of the pump activity. Fluorescently labelled drugs were detectable in the MPLSM and its distribution into the brain parenchyma could be quantified. After the end of the micropump activity, further MPLSM measurements offer the possibility to observe long term effects of the applied drug on the tumor. CONCLUSION The combination of tumor observation in the MPSLM and concurrent continuous drug delivery is a feasible and reliable method for the investigation of (novel) anti-tumor agents, especially drugs that are not blood-brain-barrier penetrant. Morphological or even functional changes of individual tumor cells can be measured under and after treatment. These techniques can be used to test new drugs targeting the tumor, its tumor microtubes and tumor cells networks, and measure the effects longitudinally.

Triadic body representations in the human cerebral cortex and peripheral nerves

2021 ◽  
pp. 133-151 ◽  
Author(s):  
Noriaki Kanayama ◽  
Kentaro Hiromitsu
Keyword(s):  
Peripheral Nerves ◽  
Sensory Modality ◽  
Body Schema ◽  
Body Representation ◽  
Neural System ◽  
The Body ◽  
Neural Representation ◽  
Structural Description ◽  
Research Fields ◽  
The Brain

Is the body reducible to neural representation in the brain? There is some evidence that the brain contributes to the functioning of the body from neuroimaging, neurophysiological, and lesion studies. Well-known dyadic taxonomy of the body schema and the body image (hereafter BSBI) is based primarily on the evidence in brain-damaged patients. Although there is a growing consensus that the BSBI exists, there is little agreement on the dyadic taxonomy because it is not a concrete and common concept across various research fields. This chapter tries to investigate the body representation in the cortex and nervous system in terms of sensory modality and psychological function using two different approaches. The first approach is to review the neurological evidence and cortical area which is related to body representation, regardless of the BSBI, and then to reconsider how we postulate the BSBI in our brain. It can be considered that our body representation could be constructed by the whole of the neural system, including the cortex and peripheral nerves. The second approach is to revisit the BSBI conception from the viewpoint of recent neuropsychology and propose three types of body representation: body schema, body structural description, and body semantics. This triadic taxonomy is considered consistent with the cortical networks based on the evidence of bodily disorders due to brain lesions. These two approaches allow to reconsider the BSBI more carefully and deeply and to give us the possibility that the body representation could be underpinned with the network in the brain.

scholarly journals Hand size underestimation grows during childhood

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Lucilla Cardinali ◽  
Andrea Serino ◽  
Monica Gori
Keyword(s):  
Motor Behavior ◽  
Sensory Modality ◽  
The Body ◽  
Typically Developing ◽  
Cognitive Representations ◽  
Hand Size ◽  
Infancy And Childhood ◽  
Sensory Modalities ◽  
Sensory Maps ◽  
The Brain

Abstract Cortical body size representations are distorted in the adult, from low-level motor and sensory maps to higher levels multisensory and cognitive representations. Little is known about how such representations are built and evolve during infancy and childhood. Here we investigated how hand size is represented in typically developing children aged 6 to 10. Participants were asked to estimate their hand size using two different sensory modalities (visual or haptic). We found a distortion (underestimation) already present in the youngest children. Crucially, such distortion increases with age and regardless of the sensory modality used to access the representation. Finally, underestimation is specific for the body as no bias was found for object estimation. This study suggests that the brain does not keep up with the natural body growth. However, since motor behavior nor perception were impaired, the distortion seems functional and/or compensated for, for proper interaction with the external environment.

scholarly journals Two-Photon Microscopy as a Tool to Study Blood Flow and Neurovascular Coupling in the Rodent Brain

2012 ◽  
Vol 32 (7) ◽  
pp. 1277-1309 ◽  
Author(s):  
Andy Y Shih ◽  
Jonathan D Driscoll ◽  
Patrick J Drew ◽  
Nozomi Nishimura ◽  
Chris B Schaffer ◽  
...  
Keyword(s):  
Blood Flow ◽  
Laser Scanning ◽  
Vascular System ◽  
Neurovascular Coupling ◽  
Laser Scanning Microscopy ◽  
Small Scale ◽  
Two Photon Microscopy ◽  
Two Photon ◽  
Rats And Mice ◽  
The Brain

The cerebral vascular system services the constant demand for energy during neuronal activity in the brain. Attempts to delineate the logic of neurovascular coupling have been greatly aided by the advent of two-photon laser scanning microscopy to image both blood flow and the activity of individual cells below the surface of the brain. Here we provide a technical guide to imaging cerebral blood flow in rodents. We describe in detail the surgical procedures required to generate cranial windows for optical access to the cortex of both rats and mice and the use of two-photon microscopy to accurately measure blood flow in individual cortical vessels concurrent with local cellular activity. We further provide examples on how these techniques can be applied to the study of local blood flow regulation and vascular pathologies such as small-scale stroke.

scholarly journals Morphological and morphometric study of pre-ovigerous and post-ovigerous adults of Tanaisia (Paratanaisia) bragai (Santos, 1934) (Digenea, Eucotylidae)

2017 ◽  
Vol 18 (2) ◽  
Author(s):  
Sthefane D'ávila ◽  
Pedro Paulo de Abreu Manso ◽  
Elizabeth Cristina de Almeida Bessa ◽  
Maria de Lurdes de Azevedo Rodrigues
Keyword(s):  
Light Microscopy ◽  
Confocal Laser Scanning Microscopy ◽  
Body Length ◽  
Laser Scanning ◽  
The Body ◽  
Laser Scanning Microscopy ◽  
Confocal Laser Scanning ◽  
Scanning Microscopy ◽  
Confocal Laser ◽  
Morphometric Study

The aim of this study was to obtain data on the morphology and morphometry of pre-ovigerous and post-ovigerous adults of the species Tanaisia (Paratanaisia) bragai, using confocal laser scanning microscopy to obtain tomographic images of the suckers and tegument. For morphometric analysis, 45 specimens (30 pre-ovigerous adults and 15 post-ovigerous adults) were measured with the aid of an ocular micrometer coupled to the objective of a photonic microscope. Pre-ovigerous and post-ovigerous adult individuals, stained with Mair carmalumen and mounted in permanent preparations, were analyzed by means of confocal laser scanning microscopy. Positive correlation was detected between the body length and ovary length of post-ovigerous adults (rs: 0.774; p<0.01), as well as between the body length and testes (rs: 0.604 and 0.659; p< 0.05), the body length and the length of uterus (rs: 0.839; p< 0,01) and between the ovary width and egg length (rs: 0.777; p<0.01). Morphological study of the pre-ovigerous adults demonstrated that the ovary and testes develop simultaneously before the development of the uterus and vitelline glands. The acetabulum was detected in pre-ovigerous adults stained with hematoxilin and observed using light microscopy. In these specimens, the acetabulum measured 36.7 ± 6.9 µm (25-50 µm) in width and 39.91 ± 6.8 µm (25-55 µm) in length. The acetabulum was not detected in post-ovigerous adults observed with light microscopy. However, this structure was detected using confocal miscrocopy. In the post-ovigerous specimens, the acetabulum presented a reduced size compared to the pre-ovigerous adults. This may imply that this structure has more functional significance in the larval and pre-ovigerous stages.

scholarly journals Genetic transformation of structural and functional circuitry rewires the Drosophila brain

eLife ◽  
2014 ◽  
Vol 3 ◽  
Author(s):  
Sonia Sen ◽  
Deshou Cao ◽  
Ramveer Choudhary ◽  
Silvia Biagini ◽  
Jing W Wang ◽  
...  
Keyword(s):  
Large Scale ◽  
Neural Circuits ◽  
Projection Neuron ◽  
Central Complex ◽  
Neuronal Progenitor ◽  
Drosophila Brain ◽  
Circuit Formation ◽  
Functional Circuitry ◽  
The Brain

Acquisition of distinct neuronal identities during development is critical for the assembly of diverse functional neural circuits in the brain. In both vertebrates and invertebrates, intrinsic determinants are thought to act in neural progenitors to specify their identity and the identity of their neuronal progeny. However, the extent to which individual factors can contribute to this is poorly understood. We investigate the role of orthodenticle in the specification of an identified neuroblast (neuronal progenitor) lineage in the Drosophila brain. Loss of orthodenticle from this neuroblast affects molecular properties, neuroanatomical features, and functional inputs of progeny neurons, such that an entire central complex lineage transforms into a functional olfactory projection neuron lineage. This ability to change functional macrocircuitry of the brain through changes in gene expression in a single neuroblast reveals a surprising capacity for novel circuit formation in the brain and provides a paradigm for large-scale evolutionary modification of circuitry.

scholarly journals Stress-induced microglial activation occurs through β-adrenergic receptor: noradrenaline as a key neurotransmitter in microglial activation

2019 ◽  
Vol 16 (1) ◽  
Author(s):  
Shuei Sugama ◽  
Takato Takenouchi ◽  
Makoto Hashimoto ◽  
Hisayuki Ohata ◽  
Yasuhiro Takenaka ◽  
...  
Keyword(s):  
Laser Scanning ◽  
Microglial Activation ◽  
Acute Stress ◽  
Underlying Mechanism ◽  
Brain Regions ◽  
Laser Scanning Microscopy ◽  
Double Knockout ◽  
Whole Brain ◽  
Β Blocker ◽  
The Brain

Abstract Background The involvement of microglia in neuroinflammatory responses has been extensively demonstrated. Recent animal studies have shown that exposure to either acute or chronic stress induces robust microglial activation in the brain. In the present study, we investigated the underlying mechanism of brain microglial activation by acute stress. Methods We first looked at the spatial distribution of the noradrenaline (NA)-synthesizing enzyme, DBH (dopamine β-hydroxylase), in comparison with NA receptors—β1, β2, and β3 adrenergic receptors (β1-AR, β2-AR, and β3-AR)—after which we examined the effects of the β-blocker propranolol and α-blockers prazosin and yohimbine on stress-induced microglial activation. Finally, we compared stress-induced microglial activation between wild-type (WT) mice and double-knockout (DKO) mice lacking β1-AR and β2-AR. Results The results demonstrated that (1) microglial activation occurred in most studied brain regions, including the hippocampus (HC), thalamus (TM), and hypothalamus (HT); (2) within these three brain regions, the NA-synthesizing enzyme DBH was densely stained in the neuronal fibers; (3) β1-AR and β2-AR, but not β3-AR, are detected in the whole brain, and β1-AR and β2-AR are co-localized with microglial cells, as observed by laser scanning microscopy; (4) β-blocker treatment inhibited microglial activation in terms of morphology and count through the whole brain; α-blockers did not show such effect; (5) unlike WT mice, DKO mice exhibited substantial inhibition of stress-induced microglial activation in the brain. Conclusions We demonstrate that neurons/microglia may interact with NA via β1-AR and β2-AR.

Three-Dimensional Reconstruction of the Rat Brain Cortical Microcirculation in vivo

1991 ◽  
Vol 11 (3) ◽  
pp. 353-360 ◽  
Author(s):  
Ulrich Dirnagl ◽  
Arno Villringer ◽  
Roland Gebhardt ◽  
Roman L. Haberl ◽  
Peter Schmiedek ◽  
...  
Keyword(s):  
Rat Brain ◽  
Laser Scanning ◽  
Brain Cortex ◽  
Three Dimensional ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Depth Of Penetration ◽  
Cranial Window ◽  
The Brain

We used confocal laser scanning microscopy (CLSM) to investigate the morphology and three-dimensional relationships of the microcirculation of the superficial layers of the rat brain cortex in vivo. In anesthetized rats equipped with a closed cranial window (dura mater removed), after i.v. injection of 3 mg/100 g of body weight of fluorescein in 0.5 ml of saline, serial optical sections of the brain cortex intraparenchymal microcirculation were taken. Excitation was at a wavelength of 488 nm (argon laser), and emission was collected above 515 nm. CLSM provided images of brain vessels with sufficient signal-to-noise ratio for three-dimensional reconstructions down to a depth of 250 μm beneath the surface of the brain. Compared to conventional fluorescence microscopy, CLSM has a much higher axial resolution and higher depth of penetration. Laser light-induced intravascular aggregates, irregularities of erythrocyte flow, or microvascular occlusions (“light and dye injury”) were not apparent in the current experimental paradigm. CLSM is a promising new tool for in vivo visualization of the cerebral microcirculation. Future studies have to characterize the potential damage to the tissue caused by the cranial window preparation and light and dye mechanisms.

scholarly journals Quantum Dot-Loaded Liposomes to Evaluate the Behavior of Drug Carriers after Oral Administration

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Kohei Tahara ◽  
Shiho Fujimoto ◽  
Fumihiko Fujii ◽  
Yuichi Tozuka ◽  
Takashi Jin ◽  
...  
Keyword(s):  
Quantum Dot ◽  
Oral Administration ◽  
Laser Scanning ◽  
Lipid Membrane ◽  
Drug Carriers ◽  
The Body ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Peptide Drug

We have developed submicron-sized liposomes modified with a mucoadhesive polymer to enhance peptide drug absorption after oral administration. Liposomal behavior in the gastrointestinal tract is a critical factor for effective peptide drug delivery. The purpose of this study was to prepare quantum dot- (QD-) loaded submicron-sized liposomes and examine liposomal behavior in the body after oral administration using in vivo fluorescence imaging. Two types of CdSe/CdZnS QDs with different surface properties were used: hydrophobic (unmodified) QDs and hydrophilic QDs with glutathione (GSH) surface modifications. QD- and GSH-QD-loaded liposomes were prepared by a thin film hydration method. Transmission electron microscopy revealed that QDs were embedded in the liposomal lipid bilayer. Conversely, GSH-QDs were present in the inner aqueous phase. Some of the GSH-QDs were electrostatically associated with the lipid membrane of stearylamine-bearing cationic liposomes. QD-loaded liposomes were detected in Caco-2 cells after exposure to the liposomes, and these liposomes were not toxic to the Caco-2 cells. Furthermore, we evaluated the in vivo bioadhesion and intestinal penetration of orally administered QD-loaded liposomes by observing the intestinal segment using confocal laser scanning microscopy.

scholarly journals New Insights into the Life Cycle of the Wheat Powdery Mildew: Direct Observation of Ascosporic Infection in Blumeria graminis f. sp. tritici

2015 ◽  
Vol 105 (6) ◽  
pp. 797-804 ◽  
Author(s):  
Tünde Jankovics ◽  
Judit Komáromi ◽  
Attila Fábián ◽  
Katalin Jäger ◽  
Gyula Vida ◽  
...  
Keyword(s):  
Life Cycle ◽  
Direct Observation ◽  
Laser Scanning ◽  
Genetic Recombination ◽  
Blumeria Graminis ◽  
Laser Scanning Microscopy ◽  
Recent Analysis ◽  
Confocal Laser ◽  
Powdery Mildews

Although Blumeria graminis is an intensively studied pathogen, an important part of its life cycle (namely, the way ascospores initiate primary infections on cereal leaves) has not yet been explored in detail. This study reports, for the first time, the direct observation of this process in B. graminis f. sp. tritici using light and confocal laser-scanning microscopy. All the germinated ascospores produced a single germ tube type both in vitro and on host plant surfaces; therefore, the ascosporic and conidial germination patterns are markedly different in this fungus, in contrast to other powdery mildews. Germinated ascospores penetrated the epidermal cells of wheat leaves and produced haustoria as known in the case of conidial infections. This work confirmed earlier studies reporting that B. graminis chasmothecia collected from the field do not contain mature ascospores, only asci filled with protoplasm; ascospore development is induced by moist conditions and is a fast process compared with other powdery mildews. Although ascosporic infections are frequent in B. graminis f. sp. tritici in the field, as shown by this study and other works as well, a recent analysis of the genomes of four isolates revealed the signs of clonal or near-clonal reproduction. Therefore, chasmothecia and ascospores are probably more important as oversummering structures than genetic recombination factors in the life cycle of this pathogen.

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