Application of the method of two-frequency biompedancemetry for the estimation of living tissue viability degree in real time

2003 ◽  
Author(s):  
A.L. Testov ◽  
D.A. Shkatov
Keyword(s):  
Real Time ◽  
Living Tissue ◽  
Tissue Viability

Per-unit-living tissue normalization of real-time RT-PCR data in ischemic rat hearts

2012 ◽  
Vol 44 (12) ◽  
pp. 651-656 ◽  
Author(s):  
S. Ellefsen ◽  
M. Bliksøen ◽  
A. Rutkovskiy ◽  
I. B. Johansen ◽  
M.-L. Kaljusto ◽  
...  
Keyword(s):  
Infarct Size ◽  
Real Time ◽  
Reference Genes ◽  
Stable Expression ◽  
Unit Weight ◽  
Living Tissue ◽  
Rt Pcr ◽  
Internal Reference ◽  
Total Rna ◽  
Rat Hearts

In studies of gene expression in acute ischemic heart tissue, internal reference genes need to show stable expression per-unit-living tissue to hinder dead cells from biasing real-time RT-PCR data. Until now, this important issue has not been appropriately investigated. We hypothesized that the expression of seven internal reference genes would show stable per-unit-living tissue expression in Langendorff-perfused rat hearts subjected to ischemia-reperfusion. This was found for cyclophilin A, GAPDH, RPL-32, and PolR2A mRNA, with GAPDH showing the highest degree of stability ( R = 0.11), suggesting unchanged rates of mRNA transcription in live cells and complete degradation of mRNA from dead cells. The infarct size-dependent degradation of GAPDH was further supported by a close correlation between changes in GAPDH mRNA and changes in RNA quality measured as RNA integrity number (R = 0.90, P < 0.05). In contrast, β-actin and 18S rRNA showed stable expression per-unit-weight tissue and a positive correlation with infarct size (R = 0.61 and R = 0.77, P < 0.05 for both analyses). The amount of total RNA extracted per-unit-weight tissue did not differ between groups despite wide variation in infarct size (7.1–50.1%). When β-actin expression was assessed using four different normalization strategies, GAPDH and geNorm provided appropriate per-unit-living expression, while 18S and total RNA resulted in marked underestimations. In studies of ischemic tissues, we recommend using geometric averaging of carefully selected reference genes for normalization of real-time RT-PCR data. A marked shift in the mRNA/rRNA ratio renders rRNA as useless for normalization purposes.

Development and validation of a real-time microelectrochemical sensor for clinical monitoring of tissue oxygenation/perfusion

2020 ◽  
Vol 12 (19) ◽  
pp. 2453-2459
Author(s):  
Gama Theophile Gnahoré ◽  
Jack L. Kelly ◽  
Saidhbhe L. O'Riordan ◽  
Fiachra B. Bolger ◽  
Michelle M. Doran ◽  
...  
Keyword(s):  
Reperfusion Injury ◽  
Real Time ◽  
Tissue Oxygenation ◽  
Clinical Monitoring ◽  
Tissue Viability ◽  
Increasing Demand ◽  
Development And Validation

Oxygen is critically important to tissue viability and there is increasing demand for its reliable real-time clinical monitoring in order to prevent, diagnose and treat several pathological disorders, including hypoxia, stroke and reperfusion injury.

scholarly journals Novel Sensor-EnabledEx VivoBioreactor: A New Approach towards Physiological Parameters and Porcine Artery Viability

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Raghavendra Mundargi ◽  
Divya Venkataraman ◽  
Saranya Kumar ◽  
Vishal Mogal ◽  
Raphael Ortiz ◽  
...  
Keyword(s):  
Real Time ◽  
Vascular Tissue ◽  
Ex Vivo ◽  
Low Oxygen ◽  
Tissue Viability ◽  
The Real ◽  
Porcine Tissue ◽  
Physiological Conditions ◽  
Bioreactor System

The aim of the present work is to design and construct anex vivobioreactor system to assess the real time viability of vascular tissue. Porcine carotid artery as a model tissue was used in theex vivobioreactor setup to monitor its viability under physiological conditions such as oxygen, pressure, temperature, and flow. The real time tissue viability was evaluated by monitoring tissue metabolism through a fluorescent indicator “resorufin.” Ourex vivobioreactor allows real time monitoring of tissue responses along with physiological conditions. Theseex vivoparameters were vital in determining the tissue viability in sensor-enabled bioreactor and our initial investigations suggest that, porcine tissue viability is considerably affected by high shear forces and low oxygen levels. Histological evaluations with hematoxylin and eosin and Masson’s trichrome staining show intact endothelium with fresh porcine tissue whereas tissues after incubation inex vivobioreactor studies indicate denuded endothelium supporting the viability results from real time measurements. Hence, this novel viability sensor-enabledex vivobioreactor acts as model to mimicin vivosystem and record vascular responses to biopharmaceutical molecules and biomedical devices.

scholarly journals Confocal Endomicroscopy of Colorectal Polyps

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Vivian M. Ussui ◽  
Michael B. Wallace
Keyword(s):  
Real Time ◽  
Disease Surveillance ◽  
Colorectal Polyps ◽  
Confocal Laser Endomicroscopy ◽  
Confocal Laser ◽  
Disruptive Technology ◽  
Living Tissue ◽  
Potential Applications ◽  
Resolution Imaging ◽  
Capillary Circulation

Confocal laser endomicroscopy (CLE) is one of several novel methods that provide real-time, high-resolution imaging at a micron scale via endoscopes. CLE has the potential to be a disruptive technology in that it can change the current algorithms that depend on biopsy to perform surveillance of high-risk conditions. Furthermore, it allows on-table decision making that has the potential to guide therapy in real time and reduce the need for repeated procedures. CLE and related technologies are often termed “virtual biopsy” as they simulate the images seen in traditional histology. However, the imaging of living tissue allows more than just pragmatic convenience; it also allows imaging of living tissue such as active capillary circulation, cellular death, and vascular and endothelial translocation, thus extending beyond what is capable in traditional biopsy. Immediate potential applications of CLE are to guide biopsy sampling in Barrett's esophagus and inflammatory bowel disease surveillance, evaluation of colorectal polyps, and intraductal imaging of the pancreas and bile duct. Data on these applications is rapidly emerging, and more is needed to clearly demonstrate the optimal applications of CLE. In this paper, we will focus on the role of CLE as applied to colorectal polyps detected during colonoscopy.

Importance of Real-Time Tissue Oximetry: Relationship to Muscle Oxygenation and Tissue Viability

2011 ◽  
Vol 169 (1) ◽  
pp. 156-161 ◽  
Author(s):  
Dirk Troitzsch ◽  
Rainer Moosdorf ◽  
Sebastian Vogt
Keyword(s):  
Real Time ◽  
Muscle Oxygenation ◽  
Tissue Viability ◽  
Tissue Oximetry

Some Recent Results in Quiescent Prominence Spectrometry

1979 ◽  
Vol 44 ◽  
pp. 41-47
Author(s):  
Donald A. Landman
Keyword(s):  
Real Time ◽  
Computer System ◽  
Spectral Response ◽  
Absolute Intensity ◽  
Solar Observatory ◽  
Target Size ◽  
Small Target ◽  
Signal Averaging ◽  
Quiescent Prominence

This paper describes some recent results of our quiescent prominence spectrometry program at the Mees Solar Observatory on Haleakala. The observations were made with the 25 cm coronagraph/coudé spectrograph system using a silicon vidicon detector. This detector consists of 500 contiguous channels covering approximately 6 or 80 Å, depending on the grating used. The instrument is interfaced to the Observatory’s PDP 11/45 computer system, and has the important advantages of wide spectral response, linearity and signal-averaging with real-time display. Its principal drawback is the relatively small target size. For the present work, the aperture was about 3″ × 5″. Absolute intensity calibrations were made by measuring quiet regions near sun center.

Video real-time imaging of artificial membranes during freeze-drying by cryo-electron microscopy

1988 ◽  
Vol 46 ◽  
pp. 16-17
Author(s):  
Alan S. Rudolph ◽  
Ronald R. Price
Keyword(s):  
Real Time ◽  
Self Assembly ◽  
Freeze Drying ◽  
Video Capture ◽  
Drying Process ◽  
Artificial Membranes ◽  
The Past ◽  
Cryo Electron Microscopy ◽  
Spherical Structures ◽  
Capture Techniques

We have employed cryoelectron microscopy to visualize events that occur during the freeze-drying of artificial membranes by employing real time video capture techniques. Artificial membranes or liposomes which are spherical structures within internal aqueous space are stabilized by water which provides the driving force for spontaneous self-assembly of these structures. Previous assays of damage to these structures which are induced by freeze drying reveal that the two principal deleterious events that occur are 1) fusion of liposomes and 2) leakage of contents trapped within the liposome [1]. In the past the only way to access these events was to examine the liposomes following the dehydration event. This technique allows the event to be monitored in real time as the liposomes destabilize and as water is sublimed at cryo temperatures in the vacuum of the microscope. The method by which liposomes are compromised by freeze-drying are largely unknown. This technique has shown that cryo-protectants such as glycerol and carbohydrates are able to maintain liposomal structure throughout the drying process.

An Interactive Minicomputer Program for the Indexing and Simulation of Electron Diffraction Patterns

1976 ◽  
Vol 34 ◽  
pp. 542-543
Author(s):  
R.P. Goehner ◽  
W.T. Hatfield ◽  
Prakash Rao
Keyword(s):  
Electron Diffraction ◽  
Real Time ◽  
Pattern Analysis ◽  
Flow Diagram ◽  
Hard Copy ◽  
Time Analysis ◽  
Real Time Analysis ◽  
Transmission Electron ◽  
One Step ◽  
Diffraction Patterns

Computer programs are now available in various laboratories for the indexing and simulation of transmission electron diffraction patterns. Although these programs address themselves to the solution of various aspects of the indexing and simulation process, the ultimate goal is to perform real time diffraction pattern analysis directly off of the imaging screen of the transmission electron microscope. The program to be described in this paper represents one step prior to real time analysis. It involves the combination of two programs, described in an earlier paper(l), into a single program for use on an interactive basis with a minicomputer. In our case, the minicomputer is an INTERDATA 70 equipped with a Tektronix 4010-1 graphical display terminal and hard copy unit.A simplified flow diagram of the combined program, written in Fortran IV, is shown in Figure 1. It consists of two programs INDEX and TEDP which index and simulate electron diffraction patterns respectively. The user has the option of choosing either the indexing or simulating aspects of the combined program.

Microstructural investigation of surface roughness in MBE-grown AlAs

1995 ◽  
Vol 53 ◽  
pp. 454-455
Author(s):  
R. Rajesh ◽  
R. Droopad ◽  
C. H. Kuo ◽  
R. W. Carpenter ◽  
G. N. Maracas
Keyword(s):  
Thin Film ◽  
Real Time ◽  
Growth Control ◽  
Native Oxide ◽  
Effusion Cell ◽  
Surface Oxide Layer ◽  
Microstructural Investigation ◽  
Mbe Growth ◽  
Film Substrate ◽  
And Control

Knowledge of material pseudodielectric functions at MBE growth temperatures is essential for achieving in-situ, real time growth control. This allows us to accurately monitor and control thicknesses of the layers during growth. Undesired effusion cell temperature fluctuations during growth can thus be compensated for in real-time by spectroscopic ellipsometry. The accuracy in determining pseudodielectric functions is increased if one does not require applying a structure model to correct for the presence of an unknown surface layer such as a native oxide. Performing these measurements in an MBE reactor on as-grown material gives us this advantage. Thus, a simple three phase model (vacuum/thin film/substrate) can be used to obtain thin film data without uncertainties arising from a surface oxide layer of unknown composition and temperature dependence.In this study, we obtain the pseudodielectric functions of MBE-grown AlAs from growth temperature (650°C) to room temperature (30°C). The profile of the wavelength-dependent function from the ellipsometry data indicated a rough surface after growth of 0.5 μm of AlAs at a substrate temperature of 600°C, which is typical for MBE-growth of GaAs.

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