METABOLISM OF [4-14C]LYNESTRENOL IN MAN

1968 ◽  
Vol 42 (2) ◽  
pp. 337-343 ◽  
Author(s):  
SORAYA KAMYAB ◽  
K. FOTHERBY ◽  
A. I. KLOPPER
Keyword(s):  
Phenolic Compounds ◽  
Enzymatic Hydrolysis ◽  
Half Life ◽  
Human Subjects ◽  
Free Fraction ◽  
Urinary Metabolites ◽  
Polar Compounds ◽  
Mean Value ◽  
Biological Half Life ◽  
Chromatographic Evidence

SUMMARY After the administration of [4-14C]lynestrenol (17α-ethynyl-19-nor-androst-4-en-17β-ol) to 7 human subjects 31·–57·6% of the dose, whether administered orally or i.v., was excreted in the urine within 5 days. The biological half-life of radioactivity was 26·5 hr. After acid and enzymatic hydrolysis, 58·7 and 45·6% respectively of the urinary radioactivity was extractable. About 10% of the urinary metabolites were excreted as sulphate conjugates. A mean value of 1·75% of the administered dose was converted to phenolic compounds. The metabolites in the free fraction and enzymehydrolysed extract of urine were almost entirely polar compounds, whereas 70% of the metabolites in the sulphate fraction were much less polar. The chromatographic evidence showed that hydroxylation of lynestrenol must have occurred at two points in the molecule. Plasma radioactivity decreased more rapidly than after administration of norethisterone.

METABOLISM OF [4-14C]NORETHISTERONE IN WOMEN

1968 ◽  
Vol 41 (2) ◽  
pp. 263-272 ◽  
Author(s):  
SORAYA KAMYAB ◽  
K. FOTHERBY ◽  
A. I. KLOPPER
Keyword(s):  
Phenolic Compounds ◽  
Enzymatic Hydrolysis ◽  
Paper Chromatography ◽  
Human Subjects ◽  
Extraction Procedure ◽  
Urinary Metabolites ◽  
Ethynyl Group ◽  
Simple Reduction

SUMMARY After the administration of norethisterone to seven human subjects 37·4% to 80·6% of the dose was excreted in the urine within 5 days. About half of the urinary radioactivity was extractable after acid or enzymatic hydrolysis and about 80% was extracted by using a serial hydrolytic and extraction procedure. About 15% of the urinary radioactivity was present as sulphate conjugates. About 5% of the urinary radioactivity was present in acidic or phenolic compounds. No metabolism of the ethynyl group seemed to occur and the Girard reaction showed that about half of the urinary metabolites were ketonic. The metabolites in the glucuronide fraction of urine were predominantly more polar on paper chromatography than tetrahydronorethisterone, whereas in the sulphate fraction most of the metabolites had a polarity similar to the simple reduction products of norethisterone. Two days after injection the plasma still contained about 5% of the administered dose.

A CHROMATOGRAPHIC STUDY OF SOME CONVERSION PRODUCTS OF ESTRONE-16-C14IN THE URINE AND FECES OF THE LAYING HEN

1962 ◽  
Vol 40 (1) ◽  
pp. 123-135 ◽  
Author(s):  
L. Ainsworth ◽  
A. L. Carter ◽  
R. H. Common
Keyword(s):  
Enzymatic Hydrolysis ◽  
Urinary Metabolites ◽  
Laying Hen ◽  
Chromatographic Study ◽  
Borohydride Reduction ◽  
Acidic Hydrolysis ◽  
Sodium Borohydride Reduction ◽  
A Minor ◽  
Chromatographic Evidence ◽  
Unidentified Metabolite

Estrone-16-C14was administered intravenously to a laying hen. The urine excreted during the succeeding 24 hours contained, on the basis of chromatographic evidence, the following radioactive conversion products of estrone: estriol, 16-epiestriol, 17-epiestriol, 16-oxoestradiol-17 β, estradiol-17 β, and 16-oxoestrone. Three other minor conversion products were not identified. 16-Oxoestradiol and 16-oxoestrone were characterized more fully by chromatographic examination of their sodium borohydride reduction products.In a second experiment, urine and feces excreted during the first two 24-hour periods after administration of estrone-16-C14were examined separately for radioactive conversion products. Of the radioactivity injected, 24.5% was recovered in the estrogen-containing extracts of the excreta. The urinary extracts contained 69% of the recovered radioactivity and the fecal extracts contained 31%.In a third experiment, recoveries of urinary metabolites after enzymatic and after acidic hydrolysis were compared. The recovery after acidic hydrolysis was approximately two-thirds of that recovered after enzymatic hydrolysis. Most of this loss could be accounted for by destruction of 16-oxoestrone and a minor unidentified metabolite during acidic hydrolysis. The distribution of the conversion products on the urinary chromatogram confirmed the results of the previous experiments.None of the experiments gave any evidence for the presence of 2-methoxyestrone, estradiol-170α, equilin, or equilenin.

scholarly journals Hydroxocobalamin

Blood ◽  
1966 ◽  
Vol 27 (2) ◽  
pp. 227-233 ◽  
Author(s):  
GEORGE B. JERZY GLASS ◽  
DUK HO LEE
Keyword(s):  
Intravenous Injection ◽  
Half Life ◽  
Intramuscular Injection ◽  
Human Subjects ◽  
Biological Half Life ◽  
Double Label ◽  
Normal Human ◽  
The Mean

Abstract The mean hepatic biological half-life of Co57-hydroxocobalamin injected to 5 normal human subjects was similar to that of Co60-cyanocobalamin, as shown by double-label hepatic surface counting during the first 30 weeks after intramuscular or intravenous injection of cobalamins. In 2 cases in whom the counting was extended over a year’s period, the clearance of hepatic radioactivity following the intramuscular injection of hydroxocobalamin has slowed down as compared to that of cyanocobalamin, between the 30th and 52nd week after injection.

A CHROMATOGRAPHIC STUDY OF SOME CONVERSION PRODUCTS OF ESTRONE-16-C14IN THE URINE AND FECES OF THE LAYING HEN

1962 ◽  
Vol 40 (1) ◽  
pp. 123-135 ◽  
Author(s):  
L. Ainsworth ◽  
A. L. Carter ◽  
R. H. Common
Keyword(s):  
Enzymatic Hydrolysis ◽  
Urinary Metabolites ◽  
Laying Hen ◽  
Chromatographic Study ◽  
Borohydride Reduction ◽  
Acidic Hydrolysis ◽  
Sodium Borohydride Reduction ◽  
A Minor ◽  
Chromatographic Evidence ◽  
Unidentified Metabolite

Estrone-16-C14was administered intravenously to a laying hen. The urine excreted during the succeeding 24 hours contained, on the basis of chromatographic evidence, the following radioactive conversion products of estrone: estriol, 16-epiestriol, 17-epiestriol, 16-oxoestradiol-17 β, estradiol-17 β, and 16-oxoestrone. Three other minor conversion products were not identified. 16-Oxoestradiol and 16-oxoestrone were characterized more fully by chromatographic examination of their sodium borohydride reduction products.In a second experiment, urine and feces excreted during the first two 24-hour periods after administration of estrone-16-C14were examined separately for radioactive conversion products. Of the radioactivity injected, 24.5% was recovered in the estrogen-containing extracts of the excreta. The urinary extracts contained 69% of the recovered radioactivity and the fecal extracts contained 31%.In a third experiment, recoveries of urinary metabolites after enzymatic and after acidic hydrolysis were compared. The recovery after acidic hydrolysis was approximately two-thirds of that recovered after enzymatic hydrolysis. Most of this loss could be accounted for by destruction of 16-oxoestrone and a minor unidentified metabolite during acidic hydrolysis. The distribution of the conversion products on the urinary chromatogram confirmed the results of the previous experiments.None of the experiments gave any evidence for the presence of 2-methoxyestrone, estradiol-170α, equilin, or equilenin.

Detection of Soluble Fibrin Monomer Complexes in Blood by Means of Protamine Sulphate Test

1968 ◽  
Vol 20 (01/02) ◽  
pp. 044-049 ◽  
Author(s):  
B Lipiński ◽  
K Worowski
Keyword(s):  
Human Subjects ◽  
Coronary Thrombosis ◽  
Mean Value ◽  
Healthy Human ◽  
Protamine Sulphate ◽  
Soluble Fibrin ◽  
Fibrin Monomer ◽  
Dog Plasma ◽  
The Mean ◽  
Precipitable Protein

SummaryIn the present paper described is a simple test for detecting soluble fibrin monomer complexes (SFMC) in blood. The test consists in mixing 1% protamine sulphate with diluted oxalated plasma or serum and reading the optical density at 6190 Å. In experiments with dog plasma, enriched with soluble fibrin complexes, it was shown that OD read in PS test is proportional to the amount of fibrin recovered from the precipitate. It was found that SFMC level in plasma increases in rabbits infused intravenously with thrombin and decreases after injection of plasmin with streptokinase. In both cases PS precipitable protein in serum is elevated indicating enhanced fibrinolysis. In healthy human subjects the mean value of OD readings in plasma and sera were found to be 0.30 and 0.11, while in patients with coronary thrombosis they are 0.64 and 0.05 respectively. The origin of SFMC in circulation under physiological and pathological conditions is discussed.

Metabolic Studies of Vitamin K1-14C and Menadione-14C in the Normal and Hepatectomized Rats

1968 ◽  
Vol 19 (03/04) ◽  
pp. 383-388 ◽  
Author(s):  
R Losito ◽  
C. A Owen ◽  
E. V Flock ◽  
Keyword(s):  
Enzymatic Hydrolysis ◽  
Oral Anticoagulants ◽  
Urinary Metabolites ◽  
The Other ◽  
Vitamin K1 ◽  
Vitamin K3 ◽  
Metabolic Studies ◽  
Intact Rats

SummaryThe metabolism of vitamin K1- 14C and menadione-14C (vitamin K3-14C) was studied in normal and hepateetomized rats. After the administration of menadione, about 70% of the 14C was excreted in the urine in 24 hrs in both types of rats. Two urinary metabolites were identified by enzymatic hydrolysis: one a glucuronide and the other a sulfate of reduced menadione. Thus, the liver is not necessary for the metabolism of menadione. In the vitamin K1 studies, the intact rats excreted only 10% of the 14C and the hepatectomized rats excreted less than 0.5%. The retention of vitamin K1 may explain its superiority over menadione as an antidote for overdosages of oral anticoagulants.

Gastroretentive System of Fluvastatin Sodium by Using Natural Mucilage and Synthetic Polymer

2014 ◽  
Vol 4 (2) ◽  
Author(s):  
Umamaheswara G. ◽  
Anudeep D.
Keyword(s):  
Half Life ◽  
Release Kinetics ◽  
Kinetic Studies ◽  
Diffusion Path ◽  
Synthetic Polymer ◽  
In Vitro Dissolution ◽  
Direct Compression ◽  
Drug Content ◽  
Biological Half Life

Fluvastatin sodium is a novel compound used as cholesterol lowering agent which acts through the inhibition of 3- hydroxyl-3- methyl glutaryl- coenzyme A (HMG-Co A) reductase. It has short biological half life (1-3h) in humans required a dosing frequency of 20 to 40mg twice a day. Due to its short variable biological half life it has been developed to a sustained gastroretentive system with a natural and synthetic polymer and to study how far the natural mucilage improves the sustained activity. Floating tablets were prepared by direct compression method using in combination of natural mucilage and synthetic polymer. Prior to the preparation of tablets the physical mixtures were subjected to FT IR studies and pre compression parameters. After preparation of tablets they were subjected to various tests like swollen index, drug content, In vitro dissolution and release kinetics with pcp disso software etc. The tablets prepared by direct compression shown good in thickness, hardness and uniformity in drug content, the prepared tablets floated more than 12h except FS1 and FS2 shows 9 and 11h. Swollen index studies shows with increase in concentration of polymer the swelling increases the diffusion path length by which the drug molecule may have to travel and cause lag time. In vitro results shows that on increasing the amount of hibiscus polymer the sustain activity is increased because of its integrity and forms a thick swollen mass and reduces the erosion property of the HypromelloseK100M, kinetic studies shows that FS 1, FS2, FS3 followed the Korsmeyer peppas model and the rest FS 4, FS 5, FS6 follows the zero order respectively. Based on n value indicating that the drug release followed super case II transport mechanism due to the erosion of the polymer.

Development and Characterization of LBG-PVA Interpenetrating Networks Incorporating Gliclazide for Sustained Release

2020 ◽  
Vol 15 ◽  
Author(s):  
Ashish Katoch ◽  
Manju Nagpal ◽  
Malkiet Kaur ◽  
Manjinder Singh ◽  
Geeta Aggarwal ◽  
...  
Keyword(s):  
Solid State ◽  
Sustained Release ◽  
Half Life ◽  
Solid State Nmr ◽  
Oral Dosage ◽  
Cross Linking ◽  
Interpenetrating Networks ◽  
Dsc Studies ◽  
Biological Half Life ◽  
Percentage Yield

Background: Controlled oral dosage forms have always been preferred for drugs with variable absorption, and short biological half life and frequent dosing. The prime goal with sustained release systems is to maintain uniform therapeutic blood levels for longer periods of time. Interpenetrating networks (IPNs) have been evidenced as uniform sustained release systems. In current study, polyvinyl alcohol (PVA) and locust bean gum (LBG) based IPNs were developed for the oral sustained release drug delivery of gliclazide (shows variable absorption). Method: The IPNs were synthesized by emulsion cross-linking method using glutaraldehyde (GA) as a cross linking agent. Gliclazide is a potential second generation, short-acting sulfonylurea oral hypoglycemic agent is having a short biological half-life (2-4 h), variable absorption and poor oral bioavailability. Various batches of IPNs were formulated by varying LBG: PVA ratio and evaluated for percentage yield, drug entrapment efficiency (DEE), swelling properties and in vitro drug release studies. Further characterizations were done by Fourier Transform Infrared Spectroscopy (FTIR), C13 Solid state NMR, X-Ray diffraction study (XRD), Scanning electron microscopy (SEM), and Differential scanning microscopy (DSC) studies. Results: The percentage yield, drug entrapment and equilibrium swelling was observed to be dependent on PVA-LBG ratio and GA amount. Sustained release of drug was observed in all IPN formulations (approx 59 - 86% in 8 h in various batches) with variable release kinetics. SEM studies revealed the regular structures of IPNs. FTIR, XRD, C13 Solid state NMR and DSC studies proposed that drug was successfully incorporated into the formed IPNs. Conclusion: IPNs of LBG and PVA can be used as a promising carrier with uniform sustained release characteristics.

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