scholarly journals New spectral imaging method for the in-vivo detection and grading of epithelial dysplasias and malignancies based on the quantitative assessment of acetic acid-tissue interaction

2002 ◽  
Author(s):  
Γεώργιος Θεμελής
Keyword(s):  
Acetic Acid ◽  
Intracellular Ph ◽  
Diagnostic Performance ◽  
Imaging Spectroscopy ◽  
Epithelial Tissue ◽  
Tissue Interaction ◽  
In Vivo Detection ◽  
Spectroscopy System ◽  
Kinetics Of

Cervical cancer is the commonest form of cancer in females under 35 years of age and the second most common in females of all ages. Limitations of the existing diagnostic methods have led to the development of new diagnostic approaches. Acetic acid is a marker used for more than 70 years in gynecology for the detection of abnormal lesions. Local application of acetic acid causes a temporal whiting to abnormal areas (acetowhite) while normal areas are not affected. Extensive clinical trials have shown that the visual assessment of acetowhitening exhibits similar diagnostic performance to other methods such as Test Pap. The diagnostic method proposed in this project is based on the quantitative and objective assessment of the acetic acid-tissue interaction by means of an Imaging Spectroscopy System. For the purpose of this study a new Imaging Spectroscopy system has been designed and developed. The method was used for the in vivo detection of dysplasias in the cervix and the results, from measurements of 181 women, indicated that there is a strong correlation between the histological condition of the tissue and the kinetics of the acetowhitening development. The best fit of the time course measurements of acetowhitening was achieved by the triple exponential function. Statistical analysis of several parameters that characterize the acetowhitening kinetics, have indicated that the combined evaluation of the parameters that express the duration (t5) and the intensity of acetowhitening (EDRmax) differentiates sufficiently all the examined histological conditions. Estimation of the sensitivity and the specificity of this method indicates that its diagnostic performance is comparable or better than that of the existing methods. In order to explain the experimental results, a model for the acetic acid-tissue interaction is proposed. According to this model the tissue-pH alterations induced by the application of acetic acid can be simulated with a 3-compartment model (the intracellular, the extracellular and the blood sink compartments). The solution of the model has shown that, after the application of acetic acid, the intracellular pH exhibits the same kinetics with the acetowhitening. The alterations of the intracellular pH cause increment in the relative refractive index of the nuclear proteins, and consequently increase the light scattering by the nuclei. Furthermore, this model correlates qualitatively the kinetics of the acetowhitening with some structural, compositional and functional features of the epithelial tissue and successfully interprets the experimental results. In particular, epithelial tissue features such as the nuclear size and inhomogeneity, the epithelium thickness, the cellular energy reserves (e.g. glycogen), the density of cell-packing, the cellular metabolism, and the efficiency of the vascularity determine the acetowhitening kinetics.

In vivo detection and staging of epithelial dysplasias and malignancies based on the quantitative assessment of acetic acid–tissue interaction kinetics

1999 ◽  
Vol 53 (1-3) ◽  
pp. 153-157 ◽  
Author(s):  
Costas J Balas ◽  
George C Themelis ◽  
Emmanuel P Prokopakis ◽  
Irene Orfanudaki ◽  
Eugenios Koumantakis ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Quantitative Assessment ◽  
Tissue Interaction ◽  
In Vivo Detection ◽  
Interaction Kinetics

Shifted excitation resonance Raman difference spectroscopy system suitable for the quantitative in vivo detection of carotenoids in human skin

2018 ◽  
Vol 15 (11) ◽  
pp. 115601 ◽  
Author(s):  
Marcel Braune ◽  
Martin Maiwald ◽  
Maxim E Darvin ◽  
Bernd Eppich ◽  
Bernd Sumpf ◽  
...  
Keyword(s):  
Human Skin ◽  
Resonance Raman ◽  
Difference Spectroscopy ◽  
In Vivo Detection ◽  
Spectroscopy System

scholarly journals Activity of indolyl-3-acetic acid oxidase and peroxidase in roots of carrot infested with Meloidogyne hapla Chiuu.

2015 ◽  
Vol 29 (1) ◽  
pp. 107-117
Author(s):  
Krystyna M. Janas
Keyword(s):  
Acetic Acid ◽  
Peroxidase Activity ◽  
Acid Oxidase ◽  
Healthy Controls ◽  
Meloidogyne Hapla ◽  
Secondary Phloem ◽  
Iaa Oxidase ◽  
Kinetics Of

IAA-oxidase and peroxidase activity was measured in storage and side roots of healthy and <i>M. hapla</i> infested carrots of two sultivars. Cultivar 'Perfekcja' is sensitive whereas cv. 'Slendero' is tolerant to the northern root-knot ne-matode. 3-, 4-, and 5-month-old plants were subjected to analyses. In <i>M. hapla</i> infested plants of both cultivars IAA-oxidase inhibitors accumulated. Kinetics of IAA oxidation <i>in vivo</i> were the same in healthy and infested plants. IAA-oxidase activity <i>in vitro</i> was inhibited in crude extracts of the infested tissues, the inhibition being prevented by PVP. Peroxidase activity increased in secondary phloem and decreased in galled side roots of both cultivars when compared with healthy controls. In galled side roots of the youngest 3-month-old plants peroxidase activity was not decreased. IAA-oxidase inhibitors accumulated in the infested roots.It is concluded that <i>M. hapla</i> has no direct effect on IAA-oxidase. Degree of tolerance to nematodes is correlated with the ratio of IAA-oxidase inhibitors to IAA-oxidase rather than with the absolute activity of IAA-oxidase.

In vivo detection of human papilloma virus-induced lesions of anogenital area after application of acetic acid: a novel and accurate approach to a trivial method

2001 ◽  
Vol 65 (2-3) ◽  
pp. 115-121 ◽  
Author(s):  
Irene M Stefanaki ◽  
Androniki D Tosca ◽  
George C Themelis ◽  
Eleftheria M Vazgiouraki ◽  
Despina N Dokianakis ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Human Papilloma Virus ◽  
Papilloma Virus ◽  
In Vivo Detection ◽  
Anogenital Area

Effect of pH and inhibitors on beta-amyloid fibril assembly

1996 ◽  
Vol 54 ◽  
pp. 752-753
Author(s):  
Beverly E. Maleeff ◽  
Timothy K. Hart ◽  
Stephen J. Wood ◽  
Ronald Wetzel
Keyword(s):  
Amyloid Fibril ◽  
Peptide Fragment ◽  
Hydrophobic Peptides ◽  
Amyloid Fibril Formation ◽  
Effects Of Ph ◽  
Severity Of The Disease ◽  
Kinetics Of ◽  
The Brain

Alzheimer's disease is characterized post-mortem in part by abnormal extracellular neuritic plaques found in brain tissue. There appears to be a correlation between the severity of Alzheimer's dementia in vivo and the number of plaques found in particular areas of the brain. These plaques are known to be the deposition sites of fibrils of the protein β-amyloid. It is thought that if the assembly of these plaques could be inhibited, the severity of the disease would be decreased. The peptide fragment Aβ, a precursor of the p-amyloid protein, has a 40 amino acid sequence, and has been shown to be toxic to neuronal cells in culture after an aging process of several days. This toxicity corresponds to the kinetics of in vitro amyloid fibril formation. In this study, we report the biochemical and ultrastructural effects of pH and the inhibitory agent hexadecyl-N-methylpiperidinium (HMP) bromide, one of a class of ionic micellar detergents known to be capable of solubilizing hydrophobic peptides, on the in vitro assembly of the peptide fragment Aβ.

Kinetics of Various 99mTc-Sn-Pyrophosphate Compounds in the Rat

1977 ◽  
Vol 16 (04) ◽  
pp. 157-162 ◽  
Author(s):  
C. Schümichen ◽  
B. Mackenbrock ◽  
G. Hoffmann
Keyword(s):  
Normal Saline ◽  
Half Life ◽  
Compound A ◽  
Short Half Life ◽  
Low Concentrations ◽  
The Stability ◽  
Kinetics Of ◽  
In Vitro Stability

SummaryThe bone-seeking 99mTc-Sn-pyrophosphate compound (compound A) was diluted both in vitro and in vivo and proved to be unstable both in vitro and in vivo. However, stability was much better in vivo than in vitro and thus the in vitro stability of compound A after dilution in various mediums could be followed up by a consecutive evaluation of the in vivo distribution in the rat. After dilution in neutral normal saline compound A is metastable and after a short half-life it is transformed into the other 99mTc-Sn-pyrophosphate compound A is metastable and after a short half-life in bone but in the kidneys. After dilution in normal saline of low pH and in buffering solutions the stability of compound A is increased. In human plasma compound A is relatively stable but not in plasma water. When compound B is formed in a buffering solution, uptake in the kidneys and excretion in urine is lowered and blood concentration increased.It is assumed that the association of protons to compound A will increase its stability at low concentrations while that to compound B will lead to a strong protein bond in plasma. It is concluded that compound A will not be stable in vivo because of a lack of stability in the extravascular space, and that the protein bond in plasma will be a measure of its in vivo stability.

Hepatobiliary Kinetics of 113mIn-Phenolphthalexon

1981 ◽  
Vol 20 (02) ◽  
pp. 90-93
Author(s):  
P.B. Parab ◽  
U.R. Raikar ◽  
R.D. Ganatra ◽  
M. C. Patel
Keyword(s):  
Biliary Excretion ◽  
Iminodiacetic Acid ◽  
Organ Distribution ◽  
Liver Uptake ◽  
On Line ◽  
Rapid Clearance ◽  
Chemical Purity ◽  
Kinetics Of ◽  
High Liver

Phenolphthalexon, a compound with iminodiacetic acid as a functional group, has been labelled with 113mIn to high chemical purity and its usefulness in studies of biliary excretion patency has been studied. Organ distribution of 113mIn-phenolphthalexon in mice was characterized by high liver uptake (50.8% of the administered dose after 5 min) and rapid clearance through the gall bladder. An animal model for studying obstruction of biliary excretion has been developed. Data on the kinetics of the radiopharmaceutical were obtained by collecting in-vivo data through an on-line computer.

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