scholarly journals I. QUANTITATIVE DETERMINATION OF THE AMOUNT OF DNA PER NUCLEUS BY INTERFERENCE MICROSCOPY

1969 ◽  
Vol 42 (2) ◽  
pp. 444-451 ◽  
Author(s):  
Cecilia Bibbiani ◽  
Roberto Tongiani ◽  
Maria Pia Viola-Magni
Keyword(s):  
Quantitative Determination ◽  
Dry Mass ◽  
Interference Microscopy ◽  
Isolated Nuclei ◽  
Adult Rat ◽  
Dnase Treatment ◽  
Dna Values ◽  
Before And After ◽  
Dna Complex

A method for the determination of the DNA content of isolated nuclei of different ploidy has been developed. It is based on measurement of the nuclear dry mass, with an integrating microinterferometer, before and after DNase treatment. The values found are slightly low, because, as indicated by biochemical determinations, consistently 5% to 8% of DNA is not extracted by DNase under these conditions. The average DNA values thus obtained for diploid and tetraploid nuclei of adult rat liver are 7.7 and 15.6 pg (10-12 g), respectively. Definite advantages of this procedure are: i) comparisons with biochemical determinations to give DNA values for each class of ploidy, ii) comparisons with histophotometry of the Feulgen dye-DNA complex to give absolute values instead of arbitrary units.

Quantitative Determination and Confirmation of Low Levels of Diethylstilbestrol in Feeds

1972 ◽  
Vol 55 (6) ◽  
pp. 1345-1353
Author(s):  
Marshall T Jeffus ◽  
Charles T Kenner
Keyword(s):  
Thin Layer ◽  
Quantitative Determination ◽  
Official Method ◽  
Trans Isomers ◽  
Cis And Trans Isomers ◽  
Before And After ◽  
Chromatographic Procedure ◽  
Low Levels ◽  
Cis And Trans

Abstract A method for the determination of diethylstibestrol in feeds, which is based on official first action method 38.048–38.051, is proposed. Interfering feed extractives are removed by using a tripotassium phosphate-Celite column prior to measurement at 415 nm before and after irradiation. Recoveries of equilibrated standards added to Soxhlet extracts of several samples averaged 94.3% compared to 86.3% by the official method. The background absorbance at 415 nm obtained by using the proposed method was approximately 6% of the background by the official method for solutions containing equivalent amounts of sample. A thin layer chromatographic method is also included for the confirmation and identification of the cis and trans isomers of the drug. The proposed method has been found satisfactory for the quantitative determination of 0.55–44 ppm diethylstilbestrol and the thin layer chromatographic procedure can detect as little as 0.07 ppm.

scholarly journals Sorption of medical preparations by chitosan

2020 ◽  
Vol 164 ◽  
pp. 06025
Author(s):  
Anna Beliaeva ◽  
Galina Nianikova
Keyword(s):  
Quantitative Determination ◽  
Sorption Capacity ◽  
Maximum Degree ◽  
Sorption Isotherms ◽  
Sorption Process ◽  
Sorption Properties ◽  
Before And After ◽  
Static Conditions ◽  
Degree Of Sorption

The article provides information about sorption properties of crab chitosan in relation to Analgin, Aspirin, Quamatel, Mydocalm, Paracetamol, Tsifran and Phtalazol. Quantitative determination of medicines’ amount before and after sorption was performed by HPLC-MS method with the preliminary plotting of calibration curves. The sorption capacity of chitosan taken in different concentrations was determined. Sorption isotherms and kinetic curves of medications’ sorption by chitosan were plotted. It has been shown that the maximum degree of sorption in static conditions for all studied medicines was achieved within an hour after the beginning of the sorption process.

scholarly journals New Improved Circular -Radial Method for Correction of Misrepresentation in Endoscope Medical Images

2019 ◽  
Vol 8 (11) ◽  
pp. 1299-1302
Keyword(s):  
Quantitative Determination ◽  
Medical Images ◽  
Regions Of Interest ◽  
Correction Algorithm ◽  
Desktop Computer ◽  
Correction Formula ◽  
Quantitative Test ◽  
Before And After ◽  
Standard Calibration

Endoscope Medical Images are distress from a spatial misrepresentation due to the wide-angle nature of the endoscope's neutral lens. This change in the size of objects with position prevents numerical measurement of the area of the objects, which is important in endoscopy for accurately measuring sore and wound sizes over time. A method for correcting the misrepresentation characteristic of endoscope images is presented. Circular –Radial correction formula was developed for the endoscope lens and validated by comparing quantitative test areas before and after the misrepresentation correction. The misrepresentation correction has been incorporated into a computer program that could readily be applied to electronic images obtained at endoscopy using a desktop computer. The research presented here is a key step towards the quantitative determination of the area of regions of interest in endoscopy. In this paper, a model for correction of misrepresentation in endoscope image is proposed. The definition of optical misrepresentation is described briefly and the theory of correction of misrepresentation using Circular Radial consisting of solid circles is presented. Three steps are used for correction, including pre-processing of grid image, correction of spatial misrepresentation and reconstruction of gray level. Finally, the corrected results are given to demonstrate the performance and validity of correction algorithm with standard calibration grid.  Circular –Radial correction formula was developed for the endoscope lens and validated by comparing quantitative test areas before and after the misrepresentation correction.  The research presented here is a key step towards the quantitative determination of the area of regions of interest in endoscopy.  Finally, the corrected results are given to demonstrate the performance and validity of correction algorithm with standard calibration grid.

scholarly journals CHANGES IN THE DNA CONTENT OF ADRENAL MEDULLA NUCLEI OF RATS INTERMITTENTLY EXPOSED TO COLD

1965 ◽  
Vol 25 (3) ◽  
pp. 415-433 ◽  
Author(s):  
Maria Pia Viola-Magni
Keyword(s):  
Aqueous Solutions ◽  
Adrenal Medulla ◽  
Dna Content ◽  
Functional Activity ◽  
Normal Values ◽  
Dry Mass ◽  
Considerable Decrease ◽  
Adult Rat ◽  
Before And After

In the adrenal medulla of rats exposed intermittently to cold (+4°C) for 100 and 300 hours, a considerable decrease (24 to 40 per cent) of the DNA content per nucleus was observed, followed by restoration to normal or above normal values within 10 days after the withdrawal of the stimulus. The findings were obtained with a scanning integrating histophotometer, and confirmed by microinterferometric investigations (on the basis of the measurement of total dry mass of nuclei isolated in aqueous medium before and after treatment with DNase) and by microchemical determinations, combined with the count of the nuclei in the homogenates. The observed decrease of DNA content cannot be attributed to errors of the methods used, nor to consequences of cellular degeneration. The available evidence seems to indicate a real decrease rather than a change in the state of a part of DNA in the nucleus in vivo whereby it becomes extractable by aqueous solutions. The restoration cannot be due to mitotic processes, which were actually never detected even with the use of colchicine, since the adrenal medulla cells in the adult rat are known to be irreversible, postmitotic cells. A correlation between the functional activity of the adrenal medulla cells and the content or state of DNA in their nuclei is demonstrated.

The Action of Juvenile Hormone on the Follicle Cells of Rhodnius Prolixus: the Importance of Volume Changes

1977 ◽  
Vol 69 (1) ◽  
pp. 33-44 ◽  
Author(s):  
RANDA ABU-HAKIMA ◽  
K. G. DAVEY
Keyword(s):  
National Research Council ◽  
Dry Mass ◽  
Rhodnius Prolixus ◽  
Interference Microscopy ◽  
Follicle Cells ◽  
Volume Changes ◽  
Cross Sectional ◽  
Original Volume ◽  
Before And After

1. The onset of vitellogenesis in Rhodnius prolixus is marked by a reduction in the height of the follicle cells. This decrease is not observed in follicle cells from allatectomized females. Estimates of the changes in cross-sectional area of the cells suggest that the cells shrink to about 50% of their original volume as the result of JH action. 2. Determination by interference microscopy of the volume of isolated living follicle cells before and after exposure to JH also suggest that the volume is reduced to 50 % of the original volume as a result of JH action. There was no decrease in volume of follicle cells from allatectomized females following exposure to JH. 3. During mid to late vitellogenesis in vivo, an increase in cell volume was measured, an increase that possibly reflects an increase in cellular dry mass. 4. It is concluded that follicle cells normally respond to JH by pumping out fluid, thus reducing their volume, and leading to the development of spaces between the cells. Note: This work is supported by the National Research Council of Canada

scholarly journals ACCELERATED AGING OF Piptadenia moniliformis (BENTH.) SEEDS

2018 ◽  
Vol 31 (3) ◽  
pp. 681-686
Author(s):  
GUTIERRES SILVA MEDEIROS AQUINO ◽  
CLARISSE PEREIRA BENEDITO ◽  
KLEANE TARGINO OLIVEIRA PEREIRA ◽  
PAULO CÉSAR DA SILVA SANTOS ◽  
JÉSSICA CHRISTIE DANTAS DE OLIVEIRA
Keyword(s):  
Seedling Emergence ◽  
Accelerated Aging ◽  
Dry Mass ◽  
Accelerated Aging Test ◽  
Aging Test ◽  
Before And After ◽  
Physiological Quality ◽  
Suitable Combination ◽  
Different Levels

ABSTRACT The accelerated aging test consists of evaluating the vigor of the seeds under conditions of high temperature and humidity, with the purpose of identifying the physiological quality of lots with similar germination. The objective of this study was to evaluate the efficiency of the accelerated aging test for classifying seed lots of P. moniliformis at different levels of vigor. Initially, the seed lots were assessed by means of seedling emergence, life velocity index, shoot length and root length, total dry mass of seedlings and determination of water content, before and after each period of aging. The experimental design for the whole world was based on a 3 × 4 factorial scheme (three seed lots and four periods of 24, 48, 72 and 96 h duration), with separate evaluations at temperatures of 38 °C and 41 °C. The accelerated aging test conducted at a temperature of 41 °C for 24 h was a more suitable combination for separating batches of P. moniliformis according to different levels of vigour, and made it possible to obtain results similar to the classification of lots in relation to the initial quality.

Quantitative determination of longitudinal and transverse cross-relaxation rates

1999 ◽  
Vol 96 (9/10) ◽  
pp. 1608-1615
Author(s):  
T. E. Malliavin ◽  
H. Desvaux ◽  
M. A. Delsuc
Keyword(s):  
Quantitative Determination ◽  
Cross Relaxation ◽  
Relaxation Rates
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