scholarly journals On the Acoustic Response of Ultrasonically - stimulated microbubbles and Enhanced Intracellular Uptake of a Fluorescent Molecule

2021 ◽  
Author(s):  
Shadab Momin
Keyword(s):  
Intracellular Uptake ◽  
Acoustic Response ◽  
Fluorescent Marker ◽  
Fluorescent Molecule ◽  
Inertial Cavitation ◽  
Negative Pressures

Effectiveness of ultrasound-and-microbubble mediated therapy depends on the acoustic response of microbubbles. In this study, the acoustic response of microbubbles in the absence and presence of cells is measured using integrated cavitation dose (ICD) over harmonics/ultraharmonics/broadband, and correlated with intracellular uptake of a fluorescent marker for varying peak-negative-pressures (PNPs). The ICD was independent of presence of cells. A PNP-threshold of 0.64 MPa was observed for microbubble’s inertial cavitation; stable cavitation (PNPs<0.64MPa) and inertial cavitation (PNPs≥0.64MPa) regimes were identified. Within inertial cavitation regime, a stronger correlation (R2>0.9) was observed between the ICD and FITC-positive cells, whereas, a weaker correlation, ranging from R2=0.59 at 3rd ultra-harmonic to R2 = 0.85 at 2nd ultra-harmonic, was observed under stable cavitation regime. The intracellular uptake, ICD and their correlation is dependent on microbubbles cavitation regime, indicating that ICD shows potential to predict bio-effects induced not only by inertial cavitation but also by stable cavitation of MBs.

scholarly journals On the Acoustic Response of Ultrasonically - stimulated microbubbles and Enhanced Intracellular Uptake of a Fluorescent Molecule

2021 ◽  
Author(s):  
Shadab Momin
Keyword(s):  
Intracellular Uptake ◽  
Acoustic Response ◽  
Fluorescent Marker ◽  
Fluorescent Molecule ◽  
Inertial Cavitation ◽  
Negative Pressures

Effectiveness of ultrasound-and-microbubble mediated therapy depends on the acoustic response of microbubbles. In this study, the acoustic response of microbubbles in the absence and presence of cells is measured using integrated cavitation dose (ICD) over harmonics/ultraharmonics/broadband, and correlated with intracellular uptake of a fluorescent marker for varying peak-negative-pressures (PNPs). The ICD was independent of presence of cells. A PNP-threshold of 0.64 MPa was observed for microbubble’s inertial cavitation; stable cavitation (PNPs<0.64MPa) and inertial cavitation (PNPs≥0.64MPa) regimes were identified. Within inertial cavitation regime, a stronger correlation (R2>0.9) was observed between the ICD and FITC-positive cells, whereas, a weaker correlation, ranging from R2=0.59 at 3rd ultra-harmonic to R2 = 0.85 at 2nd ultra-harmonic, was observed under stable cavitation regime. The intracellular uptake, ICD and their correlation is dependent on microbubbles cavitation regime, indicating that ICD shows potential to predict bio-effects induced not only by inertial cavitation but also by stable cavitation of MBs.

scholarly journals On the acoustic response of ultrasound and induced cell death

2021 ◽  
Author(s):  
Fatimah Alsaiari
Keyword(s):  
Breast Cancer ◽  
Breast Cancer Cells ◽  
Cell Membrane Permeability ◽  
Repetition Period ◽  
Acoustic Response ◽  
Inertial Cavitation ◽  
Viable Cells ◽  
Passive Cavitation Detection ◽  
Negative Pressures ◽  
Cavitation Detection

Ultrasonically-stimulated microbubbles can enhance cell membrane permeability and decrease cell viability where the underlying acoustic mechanism has been associated with both non-inertial and inertial cavitation. In this study, breast cancer cells (MDA-MB-231) were exposed to 0.5MHz ultrasound pulses of 16μs duration at varying peak negative pressures (PNP: 218kPa, 335kPa and 908kPa) and pulse repetition period (PRP 10ms and 100ms) in the presence of Definity microbubbles (3.3% v/v). The acoustic response of microbubbles was measured using passive cavitation detection with 2.25MHz transducer, and characterized by their frequency a cavitation dose (CD). Results show that the number of non-viable cells and integrated cavitation dose (ICD) significantly increases with PNP, whereas no significant differences were found between 10ms and 100ms PRPs. In this study, no correlation was found between (ICD) and cell non-viability.

scholarly journals On the acoustic response of ultrasound and induced cell death

2021 ◽  
Author(s):  
Fatimah Alsaiari
Keyword(s):  
Breast Cancer ◽  
Breast Cancer Cells ◽  
Cell Membrane Permeability ◽  
Repetition Period ◽  
Acoustic Response ◽  
Inertial Cavitation ◽  
Viable Cells ◽  
Passive Cavitation Detection ◽  
Negative Pressures ◽  
Cavitation Detection

Ultrasonically-stimulated microbubbles can enhance cell membrane permeability and decrease cell viability where the underlying acoustic mechanism has been associated with both non-inertial and inertial cavitation. In this study, breast cancer cells (MDA-MB-231) were exposed to 0.5MHz ultrasound pulses of 16μs duration at varying peak negative pressures (PNP: 218kPa, 335kPa and 908kPa) and pulse repetition period (PRP 10ms and 100ms) in the presence of Definity microbubbles (3.3% v/v). The acoustic response of microbubbles was measured using passive cavitation detection with 2.25MHz transducer, and characterized by their frequency a cavitation dose (CD). Results show that the number of non-viable cells and integrated cavitation dose (ICD) significantly increases with PNP, whereas no significant differences were found between 10ms and 100ms PRPs. In this study, no correlation was found between (ICD) and cell non-viability.

Limit Superheating of Solutions in the Region of Negative Pressures

2004 ◽  
Vol 35 (1-2) ◽  
pp. 1-9
Author(s):  
V. E. Vinogradov ◽  
P. A. Pavlov
Keyword(s):  
Negative Pressures

A Fused Thiophene-S,S-Dioxide-Based Super-Photostable Fluorescent Marker for Lipid Droplets

2020 ◽  
Author(s):  
Masayasu Taki ◽  
Keiji Kajiwara ◽  
Eriko Yamaguchi ◽  
Yoshikatsu Sato ◽  
Shigehiro Yamaguchi
Keyword(s):  
Small Molecules ◽  
Lipid Droplets ◽  
Trajectory Analysis ◽  
Super Resolution ◽  
Fluorescent Marker ◽  
Selective Staining ◽  
Fluorescent Markers ◽  
Biological Studies ◽  
Particle Level

Lipid droplets (LDs) are essential organelle in most eukaryotes, and tracking intracellular LDs dynamics using synthetic small molecules is crucial for biological studies. However, only a limited number of fluorescent markers that satisfy all requirements, such as the selective staining of LDs, high photostability, and sufficient biocompatibility, have been developed. Herein, we report a series of donor-p-acceptor dyes based on the thiophene-containing fused polycyclic scaffold [1]benzothieno[3,2-<i>b</i>][1]benzothiophene (BTBT), in which either or both thiophene rings are oxidized into thiophene-<i>S</i>,<i>S</i>-dioxide to form an electron-accepting building block. Among these dyes, LAQ1 satisfied all the aforementioned requirements, and allowed us capturing ultra-small LDs on the endoplasmic reticulum (ER) membrane by stimulation emission depletion (STED) microscopy with a super-resolution below the diffraction limit of light. Moreover, the extremely high photostability of LAQ1 enabled recording the lipolysis of LDs and the concomitant lipogenesis as well as long-term trajectory analysis of micro LDs at the single particle level in living cells.

APPLICATION OF UNCONVENTIONAL METHODS FOR FREQUENCY ANALYSIS IN ACOUSTICS

Akustika ◽  
2020 ◽  
Vol 36 (36) ◽  
pp. 25-32
Author(s):  
Jaroslav Smutný ◽  
Dušan Janoštík ◽  
Viktor Nohál
Keyword(s):  
Fourier Transform ◽  
Discrete Fourier Transform ◽  
Frequency Analysis ◽  
Mathematical Analysis ◽  
Measured Data ◽  
Application Area ◽  
Acoustic Response ◽  
Recommendations For Practice ◽  
Unconventional Methods ◽  
Frequency Area

The goal of this study is to familiarize a wider professional public with not fully known procedures suitable for processing measured data in the frequency area. Described is the use of the so-called Multi-taper method to analyze the acoustic response. This transformation belongs to a group of nonparametric methods outgoing from discrete Fourier transform, and this study includes its mathematical analysis and description. In addition, the use of respective method in a specific application area and recommendations for practice are described.

Establishment of 20 Sorghum Hybrids Fingerprints Using SSR Fluorescent Marker

2015 ◽  
Vol 41 (4) ◽  
pp. 658
Author(s):  
Rui WANG ◽  
Fu-Yao ZHANG ◽  
Qing-Jun CHENG ◽  
Cheng-Hua TIAN ◽  
Liang LING
Keyword(s):  
Fluorescent Marker

scholarly journals Swirl–nozzle interaction experiment: quasi-steady model-based analysis

2021 ◽  
Vol 62 (8) ◽  
Author(s):  
Lionel Hirschberg ◽  
Friedrich Bake ◽  
Karsten Knobloch ◽  
Angelo Rudolphi ◽  
Sebastian Kruck ◽  
...  
Keyword(s):  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Acoustic Pressure ◽  
Quantitative Information ◽  
Acoustic Response ◽  
Flow Measurements ◽  
Flow Rate Change ◽  
Interaction Experiment ◽  
Swirl Stabilized Combustion

AbstractMeasurements of sound due to swirl–nozzle interaction are presented. In the experiment a swirl structure was generated by means of unsteady tangential injection into a steady swirl-free flow upstream from a choked convergent–divergent nozzle. Ingestion of swirl by the choked nozzle caused a mass-flow rate change, which resulted in a downstream-measured acoustic response. The downstream acoustic pressure was found to remain negative as long as the swirl is maintained and reflections from the open downstream pipe termination do not interfere. The amplitude of this initial acoustic response was found to be proportional to the square of the tangential mass-flow rate used to generate swirl. When the tangential injection valve was closed, the mass-flow rate through the nozzle increased, resulting in an increase of the downstream acoustic pressure. This increase in signal was compared to the prediction of an empirical quasi-steady model, constructed from steady-state flow measurements. As the opening time of the valve was varied, the signal due to swirl evacuation showed an initial overshoot with respect to quasi-steady behavior, after which it gradually decayed to quasi-steady behavior for tangential injection times long compared to the convection time in the pipe upstream of the nozzle. This demonstrates that the acoustic signal can be used to obtain quantitative information concerning the time dependence of the swirl in the system. This could be useful for understanding the dynamics of flow in engines with swirl-stabilized combustion. Graphic abstract

Mitochondria-targeting fluorescent sensor for on-off-on response to Cu2+ and ATP in cells and zebrafish

The Analyst ◽  
2021 ◽  
Author(s):  
Wan Sun ◽  
Guofeng Liu ◽  
Mingqiong Tong ◽  
Haozhan Wang ◽  
Shuhan Liu
Keyword(s):  
Adenosine Triphosphate ◽  
Fluorescent Sensor ◽  
Biological Processes ◽  
Fluorescent Molecule ◽  
Cupric Ion ◽  
Mitochondria Targeting ◽  
In Cells

Cupric ion (Cu2+) and adenosine triphosphate (ATP) are functionally important in mitochondria and play essential roles in many important biological processes. In this work, a mitochondria-targeting fluorescent molecule Mito-A was...

scholarly journals Removal of Aerosolized Contaminants from Working Canines via a Field Wipe-Down Procedure

Animals ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 120
Author(s):  
Erin B. Perry ◽  
Dakota R. Discepolo ◽  
Stephen Y. Liang ◽  
Eileen K. Jenkins
Keyword(s):  
Povidone Iodine ◽  
Chlorhexidine Gluconate ◽  
Evidence Based ◽  
Contaminant Removal ◽  
Cross Contamination ◽  
Fourth Quadrant ◽  
Prior Work ◽  
Chemical Contaminants ◽  
Fluorescent Marker ◽  
Labrador Retrievers

Evidence-based canine decontamination protocols are underrepresented in the veterinary literature. Aerosolized microbiological and chemical contaminants can pose a risk in deployment environments highlighting the need for improved canine field decontamination strategies. Prior work has established the efficacy of traditional, water-intensive methods on contaminant removal from the coat of the working canine; however, it is not known if similar reductions can be achieved with simple field expedient methods when resources are limited. The objective of this study was to measure the reduction of aerosolized contamination via a practical “wipe-down” procedure performed on working canine coats contaminated with a fluorescent, non-toxic, water-based aerosol. Disposable, lint-free towels were saturated with one of three treatments: water, 2% chlorhexidine gluconate scrub (CHX), or 7.5% povidone-iodine scrub (PVD). Both CHX and PVD were diluted at a 1:4 ratio. Treatments were randomly assigned to one of three quadrants established across the shoulders and back of commonly utilized working dog breeds (Labrador retrievers, n = 16; German shepherds, n = 16). The fourth quadrant remained unwiped, thus serving as a control. Reduction in fluorescent marker contamination was measured and compared across all quadrants. PVD demonstrated greater marker reduction compared to CHX or water in both breeds (p < 0.0001). Reduction was similar between CHX or water in Labradors (p = 0.86) and shepherds (p = 0.06). Effective wipe-down strategies using common veterinary cleansers should be further investigated and incorporated into decontamination practices to safeguard working canine health and prevent cross-contamination of human personnel working with these animals.

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