scholarly journals Morphometrics in Developmental Neurobiology: Quantitative Analysis of Growth Cone Motility in Vivo

2017 ◽  
Author(s):  
Anokh Sohal ◽  
James Ha ◽  
Manuel Zhu ◽  
Fayha Lakhani ◽  
Kavitha Thiagaragan ◽  
...  
Keyword(s):  
Quantitative Analysis ◽  
Growth Cone ◽  
Developmental Neurobiology

Solving the mechanisms responsible for organelle behavior in vivo by same-cell correlative light and electron microscopy

1992 ◽  
Vol 50 (1) ◽  
pp. 14-15
Author(s):  
Conly L. Rieder
Keyword(s):  
Electron Microscopy ◽  
Quantitative Analysis ◽  
Light Microscopy ◽  
Living Cell ◽  
Light And Electron Microscopy ◽  
Time Behavior ◽  
Dynamic Interactions ◽  
Positive Identification ◽  
Cellular Components

The behavior of many cellular components, and their dynamic interactions, can be characterized in the living cell with considerable spatial and temporal resolution by video-enhanced light microscopy (video-LM). Indeed, under the appropriate conditions video-LM can be used to determine the real-time behavior of organelles ≤ 25-nm in diameter (e.g., individual microtubules—see). However, when pushed to its limit the structures and components observed within the cell by video-LM cannot be resolved nor necessarily even identified, only detected. Positive identification and a quantitative analysis often requires the corresponding electron microcopy (EM).

The metalloproteinase ADAM10 is required for retinal ganglion cell axon guidance in the developing visual systems

2007 ◽  
Vol 30 (4) ◽  
pp. 77
Author(s):  
Y. Y. Chen ◽  
C. L. Hehr ◽  
K. Atkinson-Leadbeater ◽  
J. C. Hocking ◽  
S. McFarlane
Keyword(s):  
Ganglion Cell ◽  
Axon Guidance ◽  
Retinal Ganglion Cell ◽  
Growth Cone ◽  
Expression Patterns ◽  
Optic Tract ◽  
Axon Growth ◽  
Proteolytic Processing ◽  
Retinal Ganglion

Background: The growth cone interprets cues in its environment in order to reach its target. We want to identify molecules that regulate growth cone behaviour in the developing embryo. We investigated the role of A disintegrin and metalloproteinase 10 (ADAM10) in axon guidance in the developing visual system of African frog, Xenopus laevis. Methods: We first examined the expression patterns of adam10 mRNA by in situ hybridization. We then exposed the developing optic tract to an ADAM10 inhibitor, GI254023X, in vivo. Lastly, we inhibited ADAM10 function in diencephalic neuroepithelial cells (through which retinal ganglion cell (RGC) axons extend) or RGCs by electroporating or transfecting an ADAM10 dominant negative (dn-adam10). Results: We show that adam10 mRNA is expressed in the dorsal neuroepithelium over the time RGC axons extend towards their target, the optic tectum. Second, pharmacological inhibition of ADAM10 in an in vivo exposed brain preparation causes the failure of RGC axons to recognize their target at low concentrations (0.5, 1 μM), and the failure of the axons to make a caudal turn in the mid-diencephalon at higher concentration (5 μM). Thus, ADAM10 function is required for RGC axon guidance at two key guidance decisions. Finally, molecular inhibition of ADAM10 function by electroporating dn-adam10 in the brain neuroepithelium causes defects in RGC axon target recognition (57%) and/or defects in caudal turn (12%), as seen with the pharmacological inhibitor. In contrast, molecular inhibition of ADAM10 within the RGC axons has no effect. Conclusions: These data argue strongly that ADAM10 acts cell non-autonomously within the neuroepithelium to regulate the guidance of RGC axons. This study shows for the first time that a metalloproteinase acts in a cell non-autonomous fashion to direct vertebrate axon growth. It will provide important insights into candidate molecules that could be used to reform nerve connections if destroyed because of injury or disease. References Hattori M, Osterfield M, Flanagan JG. Regulated cleavage of a contact-mediated axon repellent. Science 2000; 289(5483):1360-5. Janes PW, Saha N, Barton WA, Kolev MV, Wimmer-Kleikamp SH, Nievergall E, Blobel CP, Himanen JP, Lackmann M, Nikolov DB. Adam meets Eph: an ADAM substrate recognition module acts as a molecular switch for ephrin cleavage in trans. Cell 2005; 123(2):291-304. Pan D, Rubin GM. Kuzbanian controls proteolytic processing of Notch and mediates lateral inhibition during Drosophila and vertebrate neurogenesis. Cell 1997; 90(2):271-80.

Rabbit aortic medial thickness under relaxed and specified simulated in vivo conditions

1983 ◽  
Vol 245 (4) ◽  
pp. H623-H627
Author(s):  
G. Schneiderman ◽  
W. F. Pritchard ◽  
C. A. Ramirez ◽  
C. K. Colton ◽  
K. A. Smith ◽  
...  
Keyword(s):  
Quantitative Analysis ◽  
Mean Arterial Pressure ◽  
Aortic Wall ◽  
Macromolecular Transport ◽  
Liquid Silicone ◽  
Normal Mean ◽  
Longitudinal Extension ◽  
Media Layer

A method is presented for measuring the thickness of the intima-media layer of the normal rabbit descending thoracic aortic wall under both relaxed (excised) and specified simulated in vivo conditions. The in vivo conditions were simulated by maintaining the aorta in situ at its normal longitudinal extension while perfusing its lumen at the normal mean arterial pressure with a mixture of liquid silicone polymer and a catalyst, thus providing physiological radial distension. After the rubber cured, both relaxed and extended-distended tissue segments were obtained from adjacent sites on the same aorta. These tissue segments were fixed and further processed for measurement of their medial thicknesses by light microscopy. This data was used to estimate the ratio of the medial thickness of the relaxed, excised aorta to that under in vivo conditions, 1.72 +/- 0.15. This information is required for quantitative analysis of data obtained from previous studies of in vivo macromolecular transport across the rabbit thoracic aortic wall.

scholarly journals Standardization of a method to study angiogenesis in a mouse model

2013 ◽  
Vol 85 (4) ◽  
pp. 1483-1487
Author(s):  
DAVID FEDER ◽  
FABIO F. PERRAZO ◽  
EDIMAR C. PEREIRA ◽  
SILVANA FORSAIT ◽  
CECILIA K.R. FEDER ◽  
...  
Keyword(s):  
Quantitative Analysis ◽  
Animal Models ◽  
The Other ◽  
In Vivo Studies ◽  
Specific Method ◽  
Test Results ◽  
Hemoglobin Content ◽  
Physiological Conditions ◽  
Adult Organism

In the adult organism, angiogenesis is restricted to a few physiological conditions. On the other hand, uncontrolled angiogenesis have often been associated to angiogenesis-dependent pathologies. A variety of animal models have been described to provide more quantitative analysis of in vivo angiogenesis and to characterize pro- and antiangiogenic molecules. However, it is still necessary to establish a quantitative, reproducible and specific method for studies of angiogenesis factors and inhibitors. This work aimed to standardize a method for the study of angiogenesis and to investigate the effects of thalidomide on angiogenesis. Sponges of 0.5 x 0.5 x 0.5 cm were implanted in the back of mice groups, control and experimental (thalidomide 200 mg/K/day by gavage). After seven days, the sponges were removed. The dosage of hemoglobin in sponge and in circulation was performed and the ratio between the values was tested using nonparametric Mann-Whitney test. Results have shown that sponge-induced angiogenesis quantitated by ratio between hemoglobin content in serum and in sponge is a helpful model for in vivo studies on angiogenesis. Moreover, it was observed that sponge-induced angiogenesis can be suppressed by thalidomide, corroborating to the validity of the standardized method.

scholarly journals A Deep Learning Enhanced Novel Software Tool for Laryngeal Dynamics Analysis

2021 ◽  
pp. 1-15
Author(s):  
Andreas M. Kist ◽  
Pablo Gómez ◽  
Denis Dubrovskiy ◽  
Patrick Schlegel ◽  
Melda Kunduk ◽  
...  
Keyword(s):  
Neural Networks ◽  
Quantitative Analysis ◽  
High Speed ◽  
Voice Disorders ◽  
Vocal Folds ◽  
Video Data ◽  
Audio Data ◽  
Fully Automatic ◽  
Video And Audio

Purpose High-speed videoendoscopy (HSV) is an emerging, but barely used, endoscopy technique in the clinic to assess and diagnose voice disorders because of the lack of dedicated software to analyze the data. HSV allows to quantify the vocal fold oscillations by segmenting the glottal area. This challenging task has been tackled by various studies; however, the proposed approaches are mostly limited and not suitable for daily clinical routine. Method We developed a user-friendly software in C# that allows the editing, motion correction, segmentation, and quantitative analysis of HSV data. We further provide pretrained deep neural networks for fully automatic glottis segmentation. Results We freely provide our software Glottis Analysis Tools (GAT). Using GAT, we provide a general threshold-based region growing platform that enables the user to analyze data from various sources, such as in vivo recordings, ex vivo recordings, and high-speed footage of artificial vocal folds. Additionally, especially for in vivo recordings, we provide three robust neural networks at various speed and quality settings to allow a fully automatic glottis segmentation needed for application by untrained personnel. GAT further evaluates video and audio data in parallel and is able to extract various features from the video data, among others the glottal area waveform, that is, the changing glottal area over time. In total, GAT provides 79 unique quantitative analysis parameters for video- and audio-based signals. Many of these parameters have already been shown to reflect voice disorders, highlighting the clinical importance and usefulness of the GAT software. Conclusion GAT is a unique tool to process HSV and audio data to determine quantitative, clinically relevant parameters for research, diagnosis, and treatment of laryngeal disorders. Supplemental Material https://doi.org/10.23641/asha.14575533

scholarly journals On the in vivo action of erythropoietin: a quantitative analysis

1972 ◽  
Vol 51 (5) ◽  
pp. 1179-1185 ◽  
Author(s):  
Thalia Papayannopoulou ◽  
Clement A. Finch
Keyword(s):  
Quantitative Analysis

scholarly journals Isolevuglandins covalently modify phosphatidylethanolamines in vivo: Detection and quantitative analysis of hydroxylactam adducts

2009 ◽  
Vol 47 (11) ◽  
pp. 1539-1552 ◽  
Author(s):  
Wei Li ◽  
James M. Laird ◽  
Liang Lu ◽  
Sanjoy Roychowdhury ◽  
Laura E. Nagy ◽  
...  
Keyword(s):  
Quantitative Analysis ◽  
In Vivo Detection
Sign in / Sign up

Export Citation Format

Share Document