scholarly journals Prevalence and Photobiology of Photosynthetic Dinoflagellate Endosymbionts in the Nudibranch Berghia stephanieae

Animals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 2200
Author(s):  
Ruben X. G. Silva ◽  
Paulo Cartaxana ◽  
Ricardo Calado
Keyword(s):  
Food Deprivation ◽  
Photosynthetic Efficiency ◽  
Rapid Decrease ◽  
Complete Loss ◽  
Symbiotic Association ◽  
Non Invasive ◽  
Sea Slugs ◽  
Non Destructive ◽  
Over Time

Berghia stephanieae is a stenophagous sea slug that preys upon glass anemones, such as Exaiptasia diaphana. Glass anemones host photosynthetic dinoflagellate endosymbionts that sea slugs ingest when consuming E. diaphana. However, the prevalence of these photosynthetic dinoflagellate endosymbionts in sea slugs appears to be short-lived, particularly if B.stephanieae is deprived of prey that host these microalgae (e.g., during bleaching events impacting glass anemones). In the present study, we investigated this scenario, along with food deprivation, and validated the use of a non-invasive and non-destructive approach employing chlorophyll fluorescence as a proxy to monitor the persistence of the association between sea slugs and endosymbiotic photosynthetic dinoflagellates acquired through the consumption of glass anemones. Berghia stephanieae deprived of a trophic source hosting photosynthetic dinoflagellate endosymbionts (e.g., through food deprivation or by feeding on bleached E. diaphana) showed a rapid decrease in minimum fluorescence (Fo) and photosynthetic efficiency (Fv/Fm) when compared to sea slugs fed with symbiotic anemones. A complete loss of endosymbionts was observed within 8 days, confirming that no true symbiotic association was established. The present work opens a new window of opportunity to rapidly monitor in vivo and over time the prevalence of associations between sea slugs and photosynthetic dinoflagellate endosymbionts, particularly during bleaching events that prevent sea slugs from incorporating new microalgae through trophic interactions.

scholarly journals Evaluation of spectral photon counting computed tomography K-edge imaging for determination of gold nanoparticle biodistribution in vivo

Nanoscale ◽  
2017 ◽  
Vol 9 (46) ◽  
pp. 18246-18257 ◽  
Author(s):  
Salim Si-Mohamed ◽  
David P. Cormode ◽  
Daniel Bar-Ness ◽  
Monica Sigovan ◽  
Pratap C. Naha ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Quantitative Determination ◽  
Gold Nanoparticle ◽  
Photon Counting ◽  
Non Invasive ◽  
Over Time

A new spectral photon-counting CT prototype has the potential for non-invasive quantitative determination of gold nanoparticle biodistribution in vivo over time.

scholarly journals Assembly and turnover of detyrosinated tubulin in vivo.

1987 ◽  
Vol 105 (1) ◽  
pp. 265-276 ◽  
Author(s):  
D R Webster ◽  
G G Gundersen ◽  
J C Bulinski ◽  
G G Borisy
Keyword(s):  
Dynamic Instability ◽  
Human Fibroblasts ◽  
Chinese Hamster ◽  
Living Cells ◽  
Complete Loss ◽  
Almost All ◽  
Turn Over ◽  
Fixed Times ◽  
Over Time

Detyrosinated (Glu) tubulin was prepared from porcine brain and microinjected into human fibroblasts and Chinese hamster ovary (CHO) cells. Glu tubulin assembled onto the ends of preexisting microtubules and directly from the centrosome within minutes of its microinjection. Incorporation into the cytoskeleton continued until almost all of the microtubules were copolymers of Glu and tyrosinated (Tyr) tubulin. However, further incubation resulted in the progressive and ultimately complete loss of Glu-staining microtubules. Glu tubulin injected into nocodazole-treated cells was converted to Tyr tubulin by a putative tubulin/tyrosine ligase activity. The observed decrease in staining with the Glu antibody over time was used to analyze microtubule turnover in microinjected cells. The mode of Glu disappearance was analyzed quantitatively by tabulating the number of Glu-Tyr copolymers and Tyr-only microtubules at fixed times after injection. The proportion of Glu-Tyr copolymers decreased progressively over time and no segmentally labeled microtubules were observed, indicating that microtubules turn over rapidly and individually. Our results are consistent with a closely regulated tyrosination-detyrosination cycle in living cells and suggest that microtubule turnover is mediated by dynamic instability.

scholarly journals Mechanics of ultrasound elastography

2017 ◽  
Vol 473 (2199) ◽  
pp. 20160841 ◽  
Author(s):  
Guo-Yang Li ◽  
Yanping Cao
Keyword(s):  
Soft Tissues ◽  
Soft Materials ◽  
Ultrasound Elastography ◽  
Practical Applications ◽  
Linear Elastic ◽  
Non Invasive ◽  
Anisotropic Elastic ◽  
Non Destructive

Ultrasound elastography enables in vivo measurement of the mechanical properties of living soft tissues in a non-destructive and non-invasive manner and has attracted considerable interest for clinical use in recent years. Continuum mechanics plays an essential role in understanding and improving ultrasound-based elastography methods and is the main focus of this review. In particular, the mechanics theories involved in both static and dynamic elastography methods are surveyed. They may help understand the challenges in and opportunities for the practical applications of various ultrasound elastography methods to characterize the linear elastic, viscoelastic, anisotropic elastic and hyperelastic properties of both bulk and thin-walled soft materials, especially the in vivo characterization of biological soft tissues.

Abstract 15015: Multimodal in vivo Computed Tomography and Optical Imaging for Simultaneous Functional, Metabolic and Molecular Myocardial Analysis

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Elza D van Deel ◽  
Yanto Ridwan ◽  
Sasha Belenkov ◽  
Jeroen Essers
Keyword(s):  
Myocardial Infarction ◽  
Computed Tomography ◽  
Near Infrared ◽  
Left Ventricular ◽  
Ct Imaging ◽  
Diagnostic Methods ◽  
Left Ventricular Ejection ◽  
Non Invasive ◽  
Over Time

Introduction and Hypothesis: The prevalence of myocardial infarction increases with the average age of the population and is currently the leading cause of death worldwide. In order to define anatomical changes and biomarkers related to cardiac infarction, we tested the use of combined computed tomography (CT) and near infrared fluorescent (NIRF) probes to facilitate non-invasive imaging of processes concerned with tissue degeneration/regeneration. This development of new non-invasive diagnostic methods will lead to better treatment options in the future. Methods: Mice were subjected to left anterior descending artery (LAD) ligation inducing an acute myocardial infarction and subsequently imaged in vivo using fast and low dose microCT scanning (QuantumFX, Perkin Elmer) and near infrared (NIRF) probes to monitor MMP activity (MMPsense680). Immediate contrast enhanced CT imaging using eXIA160 during its blood-pool phase allowed registration of changes in ventricular anatomy and function of important global parameters, like end-diastolic volume (EDV), end-systolic volume (ESV). These were used to calculate stroke volume (SV), and left ventricular ejection fraction (LVEF). Delayed eXIA160 contrast uptake during its myocardial phase, subsequently allowed analysis of the infarct size and infarct healing. In addition, in vivo molecular MMPsense localization was combined with micro-CT imaging for accurate 3D co-registration. Results: Changes in ventricular anatomy and myocardial viability were assessed 3 hours and 2 months post LAD occlusion in the same animal, demonstrating the feasibility of monitoring myocard viability over time. The decreased uptake of eXIA160 in the myocardium was subsequently quantitated. A concomitant increase in MMP activity, as determined by fluorescence mediated tomography using MMPsense680, could be localized to the infarcted site. Conclusions: Non-invasive imaging, using NIRF probes, enables longitudinal imaging of processes concerned with myocard infarction. Consequently, disease progression can be monitored over time and the effect of (new) pharmacotherapy can be studied.

scholarly journals In-vivo measurement of strontium incorporation and retention in human bone using an x-ray fluorescence system

2021 ◽  
Author(s):  
Helen Moise
Keyword(s):  
Bone Mineral Density ◽  
Therapeutic Action ◽  
Mineral Density ◽  
X Ray ◽  
In Vivo Measurement ◽  
Non Invasive ◽  
Strontium Incorporation ◽  
Photon Source ◽  
Over Time

Stronthium (Sr), found in nature and human skeleton [sic], exerts beneficial or detrimental effects, depending on levels. Previous strontium studies in humans and animals showed bone mineral density and bone strength increases. However, its exact mechanism of therapeutic action is not fully understood. The purpose of this study was to investigate strontium incorporation and retention over time, in healthy and osteoporotic/osteopenic individuals, using the non-invasive, in-vivo X-Ray Fluorescence (IVXRF) system developed and optimized by Pejovic-Milic 2004 and Zamburlini 2008. Nine individuals, self-supplementing with strontium, were recruited and measured at their finger and ankle, representing cortical and trabecular bone. Using ¹²⁵I brachytherapy seeds as the radiation photon source, each measurement lasted thirty minutes. All individuals showed an initial rapid uptake of strontium within 2-5 months followed by slower increases, suggesting that strontium incorporation and retention is a result of two different mechanisms and is dependent on the bone remodeling cycle.

scholarly journals In-vivo measurement of strontium incorporation and retention in human bone using an x-ray fluorescence system

2021 ◽  
Author(s):  
Helen Moise
Keyword(s):  
Bone Mineral Density ◽  
Therapeutic Action ◽  
Mineral Density ◽  
X Ray ◽  
In Vivo Measurement ◽  
Non Invasive ◽  
Strontium Incorporation ◽  
Photon Source ◽  
Over Time

Stronthium (Sr), found in nature and human skeleton [sic], exerts beneficial or detrimental effects, depending on levels. Previous strontium studies in humans and animals showed bone mineral density and bone strength increases. However, its exact mechanism of therapeutic action is not fully understood. The purpose of this study was to investigate strontium incorporation and retention over time, in healthy and osteoporotic/osteopenic individuals, using the non-invasive, in-vivo X-Ray Fluorescence (IVXRF) system developed and optimized by Pejovic-Milic 2004 and Zamburlini 2008. Nine individuals, self-supplementing with strontium, were recruited and measured at their finger and ankle, representing cortical and trabecular bone. Using ¹²⁵I brachytherapy seeds as the radiation photon source, each measurement lasted thirty minutes. All individuals showed an initial rapid uptake of strontium within 2-5 months followed by slower increases, suggesting that strontium incorporation and retention is a result of two different mechanisms and is dependent on the bone remodeling cycle.

In Vivo Magnetic Resonance Spectroscopy: Applications in Psychiatry

1995 ◽  
Vol 167 (3) ◽  
pp. 299-306 ◽  
Author(s):  
Michael Maier
Keyword(s):  
Magnetic Resonance ◽  
Magnetic Resonance Spectroscopy ◽  
Brain Morphology ◽  
Resonance Spectroscopy ◽  
Disease Monitoring ◽  
Non Invasive ◽  
And Function ◽  
First Time ◽  
Non Destructive

BackgroundNuclear magnetic resonance is a non-destructive and non-invasive technology that is highly suited for research in psychiatry. It is establishing itself as a versatile means of studying brain morphology, chemistry and function and is finding a place in the diagnosis of disease, monitoring of treatment and the study of basic brain processes.MethodA literature review was undertaken.ResultsMagnetic resonance spectroscopy has been shown to distinguish between psychiatric disorders, and has provided evidence of their pathophysiological mechanisms.ConclusionsSpectroscopy in particular opens a window, for the first time, on the study of in vivo brain chemistry.

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