Copper Induced Lesions in Estuarine Teleosts

1973 ◽  
Vol 30 (3) ◽  
pp. 363-368 ◽  
Author(s):  
George R. Gardner ◽  
Gilles LaRoche
Keyword(s):  
Lateral Line ◽  
Fundulus Heteroclitus ◽  
Atlantic Silverside ◽  
Olfactory Systems ◽  
High Concentrations ◽  
Olfactory Organs ◽  
Time Required ◽  
External Exposures ◽  
The Brain ◽  
Copper Poisoning

Cellular changes attributable to copper were observed in the mechanoreceptors of the lateral line canals in the head of adult mummichog (Fundulus heteroclitus) and Atlantic silverside (Menidia menidid). The epithelium of these canals was also altered in F. heteroclitus. In both species, lesions were observed in the olfactory organs, which included the chemoreceptive sites. These manifestations of copper poisoning were evident at all studied concentrations (0.5, 1.0, and 5.0 mg/liter) of the metal. In M. menidia dilation of blood vessels was apparent, and in five cases hemorrhage had occurred in the brain and in periorbital connective tissues.Renal lesions in F. heteroclitus exposed to 1.0 and 5.0 mg/liter of copper were apparent; these changes could not be identified in M. menidia. Hepatic changes were not detectable by light microscopy in either species following external exposures to copper. High concentrations of copper administered intraperitoneally to F. heteroclitus did induce liver damage.Fry of F. heteroclitus were more sensitive to copper than were the adults or their zygotes. The emergence of larval forms from the zygote, the time required for emergence, and their survival was impaired by the metal. Lesions were not evident in developing sensory areas of the lateral line or the olfactory systems in these immature forms.

Time consumption and quality of an automated fusion tool for SPECT and MRI images of the brain

2003 ◽  
Vol 42 (05) ◽  
pp. 215-219
Author(s):  
G. Platsch ◽  
A. Schwarz ◽  
K. Schmiedehausen ◽  
B. Tomandl ◽  
W. Huk ◽  
...  
Keyword(s):  
Data Sets ◽  
3D Mri ◽  
Clinical Routine ◽  
Fusion Procedure ◽  
3D Data ◽  
Mri Scans ◽  
2D Data ◽  
Time Required ◽  
The Brain ◽  
Manual Correction

Summary: Aim: Although the fusion of images from different modalities may improve diagnostic accuracy, it is rarely used in clinical routine work due to logistic problems. Therefore we evaluated performance and time needed for fusing MRI and SPECT images using a semiautomated dedicated software. Patients, material and Method: In 32 patients regional cerebral blood flow was measured using 99mTc ethylcystein dimer (ECD) and the three-headed SPECT camera MultiSPECT 3. MRI scans of the brain were performed using either a 0,2 T Open or a 1,5 T Sonata. Twelve of the MRI data sets were acquired using a 3D-T1w MPRAGE sequence, 20 with a 2D acquisition technique and different echo sequences. Image fusion was performed on a Syngo workstation using an entropy minimizing algorithm by an experienced user of the software. The fusion results were classified. We measured the time needed for the automated fusion procedure and in case of need that for manual realignment after automated, but insufficient fusion. Results: The mean time of the automated fusion procedure was 123 s. It was for the 2D significantly shorter than for the 3D MRI datasets. For four of the 2D data sets and two of the 3D data sets an optimal fit was reached using the automated approach. The remaining 26 data sets required manual correction. The sum of the time required for automated fusion and that needed for manual correction averaged 320 s (50-886 s). Conclusion: The fusion of 3D MRI data sets lasted significantly longer than that of the 2D MRI data. The automated fusion tool delivered in 20% an optimal fit, in 80% manual correction was necessary. Nevertheless, each of the 32 SPECT data sets could be merged in less than 15 min with the corresponding MRI data, which seems acceptable for clinical routine use.

Native Ubiquitin Structural Changes Resulting from Complexation with β-methylamino-L-alanine (BMAA)

2020 ◽  
Author(s):  
Katie Mae Wilson ◽  
Aurora Burkus-Matesevac ◽  
Samuel Maddox ◽  
Christopher Chouinard
Keyword(s):  
Structural Changes ◽  
Noncovalent Complex ◽  
Unfolded Protein ◽  
Protein Size ◽  
High Concentrations ◽  
The Unfolded Protein Response ◽  
Critical Binding ◽  
Protein Response ◽  
The Brain ◽  
Lateral Sclerosis

β-methylamino-L-alanine (BMAA) has been linked to the development of neurodegenerative (ND) symptoms following chronic environmental exposure through water and dietary sources. The brains of those affected by this condition, often referred to as amyotrophic lateral sclerosis-parkinsonism-dementia complex (ALS-PDC), have exhibited the presence of plaques and neurofibrillary tangles (NFTs) from protein aggregation. Although numerous studies have sought to better understand the correlation between BMAA exposure and onset of ND symptoms, no definitive link has been identified. One prevailing hypothesis is that BMAA acts a small molecule ligand, complexing with critical proteins in the brain and reducing their function. The objective of this research was to investigate the effects of BMAA exposure on the native structure of ubiquitin. We hypothesized that formation of a Ubiquitin+BMAA noncovalent complex would alter the protein’s structure and folding and ultimately affect the ubiquitinproteasome system (UPS) and the unfolded protein response (UPR). Ion mobility-mass spectrometry revealed that at sufficiently high concentrations BMAA did in fact form a noncovalent complex with ubiquitin, however similar complexes were identified for a range of additional amino acids. Collision induced unfolding (CIU) was used to interrogate the unfolding dynamics of native ubiquitin and these Ubq-amino acid complexes and it was determined that complexation with BMAA led to a significant alteration in native protein size and conformation, and this complex required considerably more energy to unfold. This indicates that the complex remains more stable under native conditions and this may indicate that BMAA has attached to a critical binding location.

Native Ubiquitin Structural Changes Resulting from Complexation with β-methylamino-L-alanine (BMAA)

2020 ◽  
Author(s):  
Katie Mae Wilson ◽  
Aurora Burkus-Matesevac ◽  
Samuel Maddox ◽  
Christopher Chouinard
Keyword(s):  
Structural Changes ◽  
Noncovalent Complex ◽  
Unfolded Protein ◽  
Protein Size ◽  
High Concentrations ◽  
The Unfolded Protein Response ◽  
Critical Binding ◽  
Protein Response ◽  
The Brain ◽  
Lateral Sclerosis

β-methylamino-L-alanine (BMAA) has been linked to the development of neurodegenerative (ND) symptoms following chronic environmental exposure through water and dietary sources. The brains of those affected by this condition, often referred to as amyotrophic lateral sclerosis-parkinsonism-dementia complex (ALS-PDC), have exhibited the presence of plaques and neurofibrillary tangles (NFTs) from protein aggregation. Although numerous studies have sought to better understand the correlation between BMAA exposure and onset of ND symptoms, no definitive link has been identified. One prevailing hypothesis is that BMAA acts a small molecule ligand, complexing with critical proteins in the brain and reducing their function. The objective of this research was to investigate the effects of BMAA exposure on the native structure of ubiquitin. We hypothesized that formation of a Ubiquitin+BMAA noncovalent complex would alter the protein’s structure and folding and ultimately affect the ubiquitinproteasome system (UPS) and the unfolded protein response (UPR). Ion mobility-mass spectrometry revealed that at sufficiently high concentrations BMAA did in fact form a noncovalent complex with ubiquitin, however similar complexes were identified for a range of additional amino acids. Collision induced unfolding (CIU) was used to interrogate the unfolding dynamics of native ubiquitin and these Ubq-amino acid complexes and it was determined that complexation with BMAA led to a significant alteration in native protein size and conformation, and this complex required considerably more energy to unfold. This indicates that the complex remains more stable under native conditions and this may indicate that BMAA has attached to a critical binding location.

The effect of hypophysectomy on physiological color change in Fundulus heteroclitus

1971 ◽  
Vol 49 (1) ◽  
pp. 129-131 ◽  
Author(s):  
F. S. Abbott ◽  
M. B. Favreau
Keyword(s):  
Histological Examination ◽  
Fundulus Heteroclitus ◽  
Color Change ◽  
The Third ◽  
The Brain

Thirty-eight Fundulus heteroclitus were tested for ability to adapt to white and black backgrounds. They were then hypophysectomized and distributed individually to white and black containers. Their ability to adapt to background was determined for periods up to 2 weeks. Sixteen operated fish retained their preoperative ability to adapt; 8 became dark temporarily; 14 became persistently dark. Histological examination confirmed the result of the operation. In the third group of fish the persistent darkness was not associated with damage to specific areas of the brain although damage was more widespread in this group. It is concluded that hypophysectomy does not interfere with physiological color change in F. heteroclitus. The location of the central relays in the melanophore system could not be determined.

scholarly journals Use of 19F NMR Spectroscopy for Measurement of Cerebral Blood Flow: A Comparative Study Using Microspheres

1989 ◽  
Vol 9 (6) ◽  
pp. 886-891 ◽  
Author(s):  
David Barranco ◽  
Leslie N. Sutton ◽  
Sandra Florin ◽  
Joel Greenberg ◽  
Teresa Sinnwell ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Arterial Blood ◽  
Radioactive Microsphere ◽  
Low Concentrations ◽  
Cat Brain ◽  
Nmr Techniques ◽  
High Concentrations ◽  
Washout Curves ◽  
The Brain

19F NMR was used to determine washout curves of an inert, diffusible gas (CHF3) from the cat brain. The cerebral blood flow was estimated from a bi- or tri-phasic fit to the deconvoluted wash-out curve, using the Kety-Schmidt approach. Cerebral blood flow values determined by 19F NMR show the expected responsiveness to alterations in Paco2, but are approximately 28% lower than cerebral blood flow values determined simultaneously by radioactive microsphere techniques. High concentrations of CHF3 have little effect on intracranial pressure, mean arterial blood pressure or Paco2, but cause small changes in the blood flow to certain regions of the brain. We conclude that 19F NMR techniques utilizing low concentrations of CHF3 have potential for the noninvasive measurement of cerebral blood flow.

scholarly journals Brain-wide mapping of water flow perception in zebrafish

2020 ◽  
Author(s):  
Gilles Vanwalleghem ◽  
Kevin Schuster ◽  
Michael A. Taylor ◽  
Itia A. Favre-Bulle ◽  
Ethan K. Scott
Keyword(s):  
Water Flow ◽  
Lateral Line ◽  
Reverse Flow ◽  
Forward Direction ◽  
Brain Regions ◽  
Reverse Direction ◽  
Departure Point ◽  
Forward Flow ◽  
Larval Zebrafish ◽  
The Brain

AbstractInformation about water flow, detected by lateral line organs, is critical to the behavior and survival of fish and amphibians. While certain specific aspects of water flow processing have been revealed through electrophysiology, we lack a comprehensive description of the neurons that respond to water flow and the network that they form. Here, we use brain-wide calcium imaging in combination with microfluidic stimulation to map out, at cellular resolution, all neurons involved in perceiving and processing water flow information in larval zebrafish. We find a diverse array of neurons responding to forward flow, reverse flow, or both. Early in this pathway, in the lateral line ganglia, these are almost exclusively neurons responding to the simple presence of forward or reverse flow, but later processing includes neurons responding specifically to flow onset, representing the accumulated volume of flow during a stimulus, or encoding the speed of the flow. The neurons reporting on these more nuanced details are located across numerous brain regions, including some not previously implicated in water flow processing. A graph theory-based analysis of the brain-wide water flow network shows that a majority of this processing is dedicated to forward flow detection, and this is reinforced by our finding that details like flow velocity and the total volume of accumulated flow are only encoded for the simulated forward direction. The results represent the first brain-wide description of processing for this important modality, and provide a departure point for more detailed studies of the flow of information through this network.Significance statementIn aquatic animals, the lateral line is important for detecting water flow stimuli, but the brain networks that interpret this information remain mysterious. Here, we have imaged the activity of individual neurons across the entire brains of larval zebrafish, revealing all response types and their brain locations as water flow processing occurs. We find some neurons that respond to the simple presence of water flow, and others that are attuned to the flow’s direction, speed, duration, or the accumulated volume of water that has passed during the stimulus. With this information, we modeled the underlying network, describing a system that is nuanced in its processing of water flow simulating forward motion but rudimentary in processing flow in the reverse direction.

scholarly journals The representation of colored objects in macaque color patches

2017 ◽  
Author(s):  
Le Chang ◽  
Pinglei Bao ◽  
Doris Y. Tsao
Keyword(s):  
Object Recognition ◽  
Color Vision ◽  
The Other ◽  
Color Patch ◽  
Shape Information ◽  
Object Shape ◽  
Shape Invariant ◽  
High Concentrations ◽  
The Brain

AbstractAn important question about color vision is: how does the brain represent the color of an object? The recent discovery of “color patches” in macaque inferotemporal (IT) cortex, the part of brain responsible for object recognition, makes this problem experimentally tractable. Here we record neurons in three color patches, middle color patch CLC (central lateral color patch), and two anterior color patches ALC (anterior lateral color patch) and AMC (anterior medial color patch), while presenting images of objects systematically varied in hue. We found that all three patches contain high concentrations of hue-selective cells, and the three patches use distinct computational strategies to represent colored objects: while all three patches multiplex hue and shape information, shape-invariant hue information is much stronger in anterior color patches ALC/AMC than CLC; furthermore, hue and object shape specifically for primate faces/bodies are over-represented in AMC but not in the other two patches.

Behavioral and Neurophysiological Demonstration of a Lateralis Skin Photosensitivity in Larval Sea Lampreys

1991 ◽  
Vol 161 (1) ◽  
pp. 97-117 ◽  
Author(s):  
MARK RONAN ◽  
DAVID BODZNICK
Keyword(s):  
Spontaneous Activity ◽  
Lateral Line ◽  
Lateral Line Nerve ◽  
Medial Nucleus ◽  
Posterior Lateral Line ◽  
Behavioral Studies ◽  
Sea Lampreys ◽  
Response Thresholds ◽  
The Brain ◽  
Skin Photosensitivity

Larval lampreys respond to skin illumination with a delayed burst of swimming in an attempt to escape the light. The photoresponse, which is independent of the lateral eyes and pineal organs, is most readily elicited by light shone on the tail. Behavioral studies in larval lampreys demonstrate that photosensory afferents innervating the tail are carried by a trunk lateral line nerve supplying regions caudal to the head. The present results confirm that bilateral transection of this nerve in larval sea lampreys markedly diminishes the photoresponse. The trunk lateral line nerve consists of the recurrent ramus of the anterior lateral line nerve and a ramus of the posterior lateral line nerve. Bilateral transection of the recurrent ramus does not affect the photoresponse, indicating that lateralis photosensory afferents enter the brain via the posterior lateral line nerve and terminate in the medial octavolateralis nucleus. Photosensory units were subsequently recorded in the trunk lateral line nerve, posterior lateral line nerve and the lateral line area of the medulla. Medullary photosensory units were localized to the medial nucleus, previously regarded as the primary mechanosensory nucleus. Photosensory units in lateral line nerves and the brain exhibited low, irregular spontaneous activity and, after latencies of 17–4 s, responded to tail illumination with repeated impulse bursts. Response thresholds were 0.1-0.9 mWcm−2. Responses to sustained illumination were slowly adapting. A skin photosense is thus an additional lateralis modality in lampreys.

Odor Perception

2012 ◽  
pp. 44-59 ◽  
Author(s):  
Mitsuo Tonoike
Keyword(s):  
Signal Transduction ◽  
Central Nervous System ◽  
Nervous System ◽  
Information Processing ◽  
Non Invasive ◽  
Olfactory Acuity ◽  
Central Regions ◽  
Olfactory Systems ◽  
The Central Nervous System ◽  
The Brain

Though olfaction is one of the necessary senses and indispensable for the maintenance of the life of the animal, the mechanism of olfaction had not yet been understood well compared with other sensory systems such as vision and audition. However, recently, the most basic principle of “signal transduction on the reception and transmission for the odor” has been clarified. Therefore, the important next problem is how the information of odors about is processed in the Central Nervous System (CNS) and how odor is perceived in the human brain. In this chapter, the basic olfactory systems in animal and human are described and examples such as “olfactory acuity, threshold, adaptation, and olfactory disorders” are discussed. The mechanism of olfactory information processing is described under the results obtained by using a few new non-invasive measuring methods. In addition, from a few recent studies, it is shown that olfactory neurophysiological information is passing through some deep central regions of the brain before finally being processed in the orbito-frontal areas.

scholarly journals Distribution and stability of antisense phosphorothioate oligonucleotides in rodent brain following direct intraparenchymal controlled-rate infusion

1997 ◽  
Vol 3 (5) ◽  
pp. E6 ◽  
Author(s):  
William C. Broaddus ◽  
Sujit S. Prabhu ◽  
George T. Gillies ◽  
Jeffrey Neal ◽  
William S. Conrad ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Structural Changes ◽  
Tissue Concentration ◽  
Volume Of Distribution ◽  
Brain Parenchyma ◽  
Average Concentration ◽  
High Flow ◽  
Fischer 344 ◽  
High Concentrations ◽  
The Brain

High-flow microinfusion is a novel technique for delivery of compounds directly into the brain parenchyma, bypassing the blood-brain barrier. The feasibility of this technique has been demonstrated with low-molecular-weight compounds, macromolecular dyes, and proteins. Delivery of antisense oligonucleotides into the brain parenchyma represents an additional potential application of this technique not previously described. In this report, the authors examined the distribution and disposition of phosphorothioate oligodeoxynucleotide (PS-ODN) infused for this reason. An 18-mer 35S-PS-ODN (molecular weight approximately 6000) was infused over 1 hour into the caudate putamen of Fischer 344 rats. At 1, 6, 12, 24, and 48 hours after beginning the infusion, the brains were extracted and analyzed using quantitative autoradiographic techniques. Cerebrospinal fluid (CSF) was also aspirated from the cisterna magna and analyzed for radioactivity and stability of the 35S-PS-ODN. At 1 hour, the infused ODN was uniformly distributed in brain tissue, with a maximum average concentration of 4806.5 ± 210.5 nCi/g. This represents a tissue concentration of 19.2 ± 0.84 μM. Extensive spread into surrounding parenchyma was observed over the ensuing 47 hours. The 35S-PS-ODN radioactivity peaked in the CSF at the end of the 1-hour infusion, containing 10% (50 ± 20 nCi) of the infused radioactivity. Activity then decayed exponentially over 11 hours, stabilizing at a lower CSF content of 0.2% (1 ± 0.1 nCi). The volume of distribution (Vd) was 105 ± 7.9 mm3 at 1 hour, representing a ratio of Vd/Vi (volume of infusion) of 5.2. The Vd increased to 443.4 ± 62.3 mm3 at the end of 48 hours, whereas the average minimum tissue concentration decreased from 15.2 to 3.2 μM. Undegraded 18-mer was seen throughout the 48-hour period using 20% polyacrylamide/7M urea gel electrophoresis. The animals tolerated the infusion without evidence of toxicity, and minimal structural changes in tissue were observed on histological examination. Thus, PS-ODN can be safely delivered in high concentrations to wide areas of the rat brain by using high-flow microinfusion, and the concentrations remain stable even after 48 hours in situ.

Sign in / Sign up

Export Citation Format

Share Document