Blood plasma levels and urinary excretion of ascorbic acid before and after a test dose in children with severe thalassemia

1961 ◽  
Vol 59 (3) ◽  
pp. 361-369 ◽  
Author(s):  
C. Choremis ◽  
Cleopatra Economou-Mavrou ◽  
M. Gregoriou
Keyword(s):  
Ascorbic Acid ◽  
Urinary Excretion ◽  
Blood Plasma ◽  
Plasma Levels ◽  
Test Dose ◽  
Before And After

Effects of fasting on blood plasma levels, metabolism and metabolic effects of epinephrine and norepinephrine in steers

1988 ◽  
Vol 118 (2) ◽  
pp. 254-259 ◽  
Author(s):  
Daniel Fröhli ◽  
Jürg W. Blum
Keyword(s):  
Fatty Acids ◽  
Blood Plasma ◽  
Plasma Levels ◽  
Food Restriction ◽  
Metabolic Effects ◽  
Immunoreactive Insulin ◽  
Metabolic Clearance ◽  
Clearance Rates ◽  
Nonesterified Fatty Acids ◽  
Before And After

Abstract. Experiments were designed to study effects of 3 days of fasting on blood plasma levels, metabolic clearance rates (MCR) and effects of norepinephrine (NE) and epinephrine (E) on levels of glucose, nonesterified fatty acids (NEFA) and immunoreactive insulin (IRI) in 12 steers. During fasting, levels of E, NE and protein did not change, whereas IRI, T3 and glucose decreased and NEFA, acetoacetate and β-hydroxybutyrate increased. Before and at the end of fasting, NE or E were iv infused for 120 min. NE and E were elevated after 15 min and to the end of the infusion. The increase in E, but not in NE, was significantly greater after 3 days of fasting than before fasting (P < 0.05). MCR for E was lower after fasting (299 ± 17 vs 204 ± 10 ml·kg−0.75·min−1; P < 0.001), whereas MCR for NE was not significantly different (455 ± 37 vs 400 ±27 ml·kg−0.75·min−1). MCR was higher for NE than for E, both before and after fasting (P < 0.05). After the infusions, E and NE decreased within minutes to pre-infusion concentrations. During E infusions, NEFA increased significantly more, whereas glucose increased less in fasted than in fed animals. During NE infusions, NEFA increased in fasted, but not in fed animals, and glucose increased less at the end than before fasting. IRI decreased during E infusions only in fed animals, and transiently increased after the infusion, except after NE infusion in fasted steers. Changes in plasma levels, clearance rates and sensitivity to effects of NE and E, together with alterations of insulin and T3 concentrations, may contribute to shifts in energy metabolism during food restriction.

A Study on the Relation and Adjustment of Blood Plasma Level and Urinary Excretion of Ascorbic Acid to Intake

1950 ◽  
Vol 40 (2) ◽  
pp. 255-263 ◽  
Author(s):  
Mary L. Dodds ◽  
Echo L. Price ◽  
Florence L. MacLeod
Keyword(s):  
Ascorbic Acid ◽  
Plasma Level ◽  
Urinary Excretion ◽  
Blood Plasma

scholarly journals Absorption of Cobalt60-Labeled Vitamin B12 After Subtotal Gastrectomy

Blood ◽  
1958 ◽  
Vol 13 (4) ◽  
pp. 339-347 ◽  
Author(s):  
FRITZ LOEWENSTEIN
Keyword(s):  
Urinary Excretion ◽  
Vitamin B12 ◽  
Proximal Gastrectomy ◽  
Intrinsic Factor ◽  
Subtotal Gastrectomy ◽  
Test Dose ◽  
Distal Portion ◽  
Normal Vitamin ◽  
Before And After ◽  
Vitamin B12 Absorption

Abstract Vitamin B12 absorption has been studied in patients with subtotal gastrectomy by means of the Co60 B12 urinary excretion test. Five patients tested before and after a conventional subtotal gastrectomy showed no significant change in absorption. Of 22 patients who were tested at various intervals after a conventional (distal) subtotal gastrectomy, 19 had normal vitiamin B12 absorption and three had low absorption that was corrected to normal by giving gastric juice with the test dose. Three patients who had had a proximal gastrectomy showed normal vitamin B12 absorption, indicating that intrinsic factor was being produced by the remaining distal portion of the stomach.

PLASMA LEVELS OF ESTRONE SULFATE, ESTRONE AND ESTRADIOL-17β IN THE COW AROUND PARTURITION

1975 ◽  
Vol 55 (4) ◽  
pp. 509-512 ◽  
Author(s):  
C. P. W. TSANG ◽  
A. J. HACKETT ◽  
E. M. TURNER Jr.
Keyword(s):  
Blood Plasma ◽  
Plasma Levels ◽  
Late Pregnancy ◽  
Blood Collection ◽  
Estrone Sulfate ◽  
Individual Variations ◽  
Before And After ◽  
The Mean ◽  
Estradiol 17Β ◽  
In Blood Plasma

Estrone sulfate, estrone, and estradiol-17β have been assayed in blood plasma taken from the mammary vein of five pregnant cows before and after parturition. While there were considerable individual variations, the mean plasma levels of estrone sulfate (13.4 ng/ml), estrone (1 ng/ml) and estradiol-17β (1 ng/ml) remained fairly constant over the period of blood collection prior to parturition (−88 h to −2 h). The levels of all three estrogens dropped rapidly within 8 h postpartum. It is concluded that estrone sulfate, rather than estrone, is the predominant plasma estrogen in late pregnancy in the cow.

Sorbitol enhances the physicochemical stability of B12 vitamers

2020 ◽  
Vol 90 (5-6) ◽  
pp. 439-447 ◽  
Author(s):  
Andrew Hadinata Lie ◽  
Maria V Chandra-Hioe ◽  
Jayashree Arcot
Keyword(s):  
Ascorbic Acid ◽  
Uv Light ◽  
Heat Exposure ◽  
Water Soluble ◽  
Uv Exposure ◽  
Physicochemical Stability ◽  
Before And After ◽  
The Stability

Abstract. The stability of B12 vitamers is affected by interaction with other water-soluble vitamins, UV light, heat, and pH. This study compared the degradation losses in cyanocobalamin, hydroxocobalamin and methylcobalamin due to the physicochemical exposure before and after the addition of sorbitol. The degradation losses of cyanocobalamin in the presence of increasing concentrations of thiamin and niacin ranged between 6%-13% and added sorbitol significantly prevented the loss of cyanocobalamin (p<0.05). Hydroxocobalamin and methylcobalamin exhibited degradation losses ranging from 24%–26% and 48%–76%, respectively; added sorbitol significantly minimised the loss to 10% and 20%, respectively (p < 0.05). Methylcobalamin was the most susceptible to degradation when co-existing with ascorbic acid, followed by hydroxocobalamin and cyanocobalamin. The presence of ascorbic acid caused the greatest degradation loss in methylcobalamin (70%-76%), which was minimised to 16% with added sorbitol (p < 0.05). Heat exposure (100 °C, 60 minutes) caused a greater loss of cyanocobalamin (38%) than UV exposure (4%). However, degradation losses in hydroxocobalamin and methylcobalamin due to UV and heat exposures were comparable (>30%). At pH 3, methylcobalamin was the most unstable showing 79% degradation loss, which was down to 12% after sorbitol was added (p < 0.05). The losses of cyanocobalamin at pH 3 and pH 9 (~15%) were prevented by adding sorbitol. Addition of sorbitol to hydroxocobalamin at pH 3 and pH 9 reduced the loss by only 6%. The results showed that cyanocobalamin was the most stable, followed by hydroxocobalamin and methylcobalamin. Added sorbitol was sufficient to significantly enhance the stability of cobalamins against degradative agents and conditions.

Pharmacodynamics of [D-Ser (t-Bu), Des-Gly]GnRH ethylamide (Buserelin®) in 6 normal volunteers.

1987 ◽  
Vol 115 (2) ◽  
pp. 235-242 ◽  
Author(s):  
Y. Reznik ◽  
B. P. Winiger ◽  
M. L. Aubert ◽  
P. C. Sizonenko
Keyword(s):  
Urinary Excretion ◽  
Precocious Puberty ◽  
Plasma Levels ◽  
Intranasal Administration ◽  
Cross Reaction ◽  
Disappearance Rate ◽  
Gnrh Analog ◽  
Male Adolescents ◽  
Normal Volunteers ◽  
The Mean

Abstract. The disappearance rate of [D-Ser(t-bu)6,des-Gly10]GnRH ethylamide (Buserelin®, HOE 766) was studied in plasma and urine after intranasal (300 μg) or sc (10 μg/kg) administration. A radioimmunoassay for HOE 766 was developed using 125I[D-Trp6,Des-Gly10]GnRH ethylamide as tracer and an antiserum raised against HOE 766. Cross-reaction with native GnRH was only 1.7%. Sensitivity was 1 pg/tube. In 6 male adolescents, the mean plasma HOE 766 concentration (± sem) was 0.46 ± 0.08, 0.50 ± 0.10, 0.28 ± 0.04, 0.24 ± 0.04, 0.13 ± 0.03, and 0.08 ± 0.02 μg/l 30, 60, 90, 120 and 180 min after the intranasal administration, respectively. Concomitant urinary excretion of HOE 766-like material was 9.43 ± 1.96 μg/4 h. There was a good correlation between integrated plasma levels and urinary excretion (r = 0.92). In the same 6 volunteers, the plasma HOE 766 levels were 21.2 ± 3.0, 25.9 ± 0.8, 21.2 ± 0.9, 17.1 ± 0.7, 12.8 ± 1.1, 8.9 ± 0.4, and 5.9 ± 0.8 μg/l 20, 40, 60, 90, 120, 180 and 240 min after sc injection, respectively. The mean urinary excretion was 543 ± 61 μg/4 h. In two girls with precocious puberty treated during 12 to 15 months with intranasal administration of HOE 766, urinary excretion of HOE 766-like material was shown to correlate well with the degree of inhibition of plasma 17β-E2and of plasma LH and FSH responses to a GnRH challenge. Thus, monitoring of HOE 766 in urine appears to be helpful for evaluating of intranasal therapy with a GnRH analog in precocious puberty.

Assessment of Color Stability of Treated Leathers with Silicone Oil and Polyethylene Glycol

2014 ◽  
Vol 1 (1) ◽  
pp. 24-34
Author(s):  
Alireza K. ◽  
Hossein Ahmadi ◽  
Mohsen Mohammadi
Keyword(s):  
Ascorbic Acid ◽  
Polyethylene Glycol ◽  
Treatment Process ◽  
Color Change ◽  
Silicone Oil ◽  
Accelerated Aging ◽  
Color Stability ◽  
Antioxidant Additive ◽  
Before And After ◽  
Aesthetic Values

Lubricants and leather dressings are the most common treatments of dry and water logged historical leathers. Color change has a great importance during the time and treatment process, due to visual and aesthetic values of historic leather relics. Polyethylene glycol (PEG) and silicone oil (SiO) are frequently used leather dressings in the conservation procedures. Therefore, color stability of treated leathers with PEG and SiO were investigated before and after heat accelerated aging. Moreover, application of ascorbic acid was evaluated as an antioxidant additive for PEG (PEG+AA).Color change after treatment and aging were studied by colorimetry technique in the CIE *L*a*b system. Results indicated to severe color alteration in PEG treated and aged leathers with or without ascorbic acid. Whereas, SiO treated samples showed better stability and minimum color shift after aging. Silicone oil was characterized as the best dressing for historical leathers with compared to PEG and PEG+AA, due to its high stability and aesthetical properties.

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