STUDIES ON THYROIDAL COLLOID PINOCYTOSIS USING A DOUBLE ISOTOPE TECHNIQUE

1972 ◽  
Vol 70 (1) ◽  
pp. 48-55 ◽  
Author(s):  
Mario A. Pisarev ◽  
Noe Altschuler ◽  
Leslie J. DeGroot
Keyword(s):  
Acid Phosphatase ◽  
Thyroid Hormone ◽  
Trichloroacetic Acid ◽  
Specific Activity ◽  
Acid Precipitation ◽  
Solvent System ◽  
Blood Stream ◽  
Radioactive Materials ◽  
Isotope Technique ◽  
Double Isotope

ABSTRACT The process of secretion of the thyroid hormone involves several steps: pinocytosis of thyroglobulin, fusion of the colloid droplets with the lysosomes, digestion of thyroglobulin by a cathepsin, dehalogenation of tyrosines and release of thyronines into the blood stream. The present paper describes a double isotope technique for studying the first two steps. Thyrotrophin (TSH) administration to rats increased the radioactivity present in all fractions, specially in the 15 000 × g pellet. When the subcellular distribution of acid phosphatase was determined, the highest specific activity was found in this fraction, thus indicating the presence of lysosomes. The content of radioactive materials in the 15 000 × g pellet was analyzed by trichloroacetic acid precipitation and by ascending paper chromatography using n-butanol:ethanol:ammonium hydroxide (5:1:2;v/v) as solvent system. The results obtained showed that 90% of the radioactivity was protein bound and strongly suggest that this material is thyroglobulin.

An alternative method for assaying cerebrospinal fluid protein in the presence of methotrexate.

1988 ◽  
Vol 34 (10) ◽  
pp. 2091-2092 ◽  
Author(s):  
L M Kasper ◽  
W R Moorehead ◽  
T O Oei ◽  
M Markanich
Keyword(s):  
Cerebrospinal Fluid ◽  
Hydrochloric Acid ◽  
Trichloroacetic Acid ◽  
Dilute Hydrochloric Acid ◽  
Constant Amount ◽  
Manual Method ◽  
Turbidimetric Method ◽  
Methotrexate Concentration ◽  
Cerebrospinal Fluid Protein ◽  
Positive Interference

Abstract Therapeutic concentrations of methotrexate can cause significant positive interference in cerebrospinal fluid (CSF) protein values when assayed in the Du Pont aca. Conversely, our modified turbidimetric method, in which trichloroacetic acid (TCA) plus a sample blank containing dilute hydrochloric acid is used in place of TCA, exhibits little or no interference from methotrexate. This was verified by assaying solutions that contained a constant amount of protein (approximately 430 mg/L) and various amounts of methotrexate (0.0-2.3 x 10(-4) mol/L) by both the Du Pont aca and the manual turbidimetric method. As expected, the aca results showed increasing protein values with increasing methotrexate, whereas the manual method gave results approximating the expected protein value irrespective of the methotrexate concentration.

Synthesis and Molecular Structure of Disulfane

1991 ◽  
Vol 46 (10) ◽  
pp. 1338-1342 ◽  
Author(s):  
Josef Hahn ◽  
Petra Schmidt ◽  
Klaus Reinartz ◽  
Jörg Behrend ◽  
Gisbert Winnewisser ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Dihedral Angle ◽  
Trichloroacetic Acid ◽  
Microwave Spectroscopy ◽  
Stabilizing Agent ◽  
Rotary Evaporator ◽  
First Time

The synthesis and structure of disulfane are presented. Pure disulfane, H2S2, has been obtained by the cracking distillation of raw sulfane mixtures in a rotary evaporator, thus substituting the classical cracking column for the rotating flask of the evaporator. Pure, gaseous dideuterodisulfane could be generated by the solvolysis of bis(methyldiphenylsilyl)disulfane, (MePh2Si)2S2, with D2O in the presence of trichloroacetic acid as stabilizing agent. Partially deuterated disulfane has been prepared by H,D exchange between pure H2S2 and DCl. For the first time the molecular structure of HSSH has been determined based solely on microwave spectroscopy with the following parameters: r(SS) = 2.0564 A, r(SH) = 1.3421 A, dihedral angle γ = 90.34°, and <(SSH) = 97.88°.

Simultaneous Deep-Plane Face Lift and Trichloroacetic Acid Peel

1994 ◽  
Vol 93 (1) ◽  
pp. 86-93 ◽  
Author(s):  
David L. Dingman ◽  
Jeffrey Hartog ◽  
Maria Siemionow
Keyword(s):  
Trichloroacetic Acid ◽  
Face Lift ◽  
Plane Face
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