The Physiology Of Excretion In A Blood-Sucking Insect, Rhodnius Prolixus (Hemiptera, Reduviidae)

1931 ◽  
Vol 8 (4) ◽  
pp. 443-451 ◽  
Author(s):  
V. B. WIGGLESWORTH
Keyword(s):  
Uric Acid ◽  
Neutral Red ◽  
Alkaline Ph ◽  
Lower Segment ◽  
Uric Acid Excretion ◽  
Malpighian Tube ◽  
Blood Sucking ◽  
Rectal Glands ◽  
Relative Solubility ◽  
Different Levels

A theory of uric acid excretion is put forward according to which potassium or sodium acid urate is secreted in solution in the upper part of the Malpighian tube, and water and base reabsorbed from the lower part of the tube, leading to a precipitation of free uric acid; so that the same water and base are circulated and used repeatedly. The evidence for this theory is presented under four heads: (i) General evidence from the histology of the Malpighian tube and the relative solubility of uric acid and urates. (ii) Experiments with vital dyes. Thus, neutral red is taken up from the blood by the upper segment of the Malpighian tube, and from the lumen of the tube in the lower segment. It is suggested that water follows the same route. (iii) The application of ligatures to the tubes at different levels shows that uric acid is not secreted by the lower segment. (iv) Experiments with indicators show that the contents of the tube are faintly alkaline (pH 7.2) in the upper segment, and acid (pH 6.6) in the lower segment. Uric acid in solution has a pH about6.5. It is suggested that the terminal ampullae of the Malpighian tubes, and possibly the rectal glands, also play a part in the reabsorption of water

scholarly journals The Physiology Of Excretion In A Blood-Sucking Insect, Rhodnius Prolixus (Hemiptera, Reduviidae)

1931 ◽  
Vol 8 (4) ◽  
pp. 411-427
Author(s):  
V. B. WIGGLESWORTH
Keyword(s):  
Uric Acid ◽  
Alkaline Ph ◽  
Clear Fluid ◽  
Sodium Potassium ◽  
Blood Sucking ◽  
Calcium Magnesium ◽  
Single Meal ◽  
Semi Solid ◽  
Almost All ◽  
Sodium And Potassium

An adult Rhodnius will ingest from two to three times its weight of blood at a single meal, and about three-quarters of the water in this blood is excreted as a clear fluid during the next three or four hours. This fluid is alkaline (pH 7.8), more or less isotonic with the blood (sp. gr. 1.007; Δ = 0.62-0.68), and serves for the elimination of most of the sodium and potassium chlorides in the meal. It also contains urea, bicarbonate, sulphate and uric acid. After the first day, the urine gradually becomes acid (pH 6.0-6.5 and much more concentrated, and contains a yellow pigment. Uratic spheres appear and increase in number until the urine is semi-solid. The urine now contains only traces of sodium, potassium, chloride and urea. There are small amounts of calcium, magnesium, phosphate, sulphate, creatine and probably amino acids. There is never any ammonia. Almost all the nitrogen is excreted as uric acid. This is in the form of minute spheres with radial striation, in which about 80 to 90 per cent, of the uric acid is free; the rest, presumably, as sodium and potassium acid urate.

Effect of urine flow rate on uric acid excretion in man

1972 ◽  
Vol 15 (4) ◽  
pp. 338-346 ◽  
Author(s):  
Herbert S. Diamond ◽  
Robert Lazarus ◽  
David Kaplan ◽  
David Halberstam
Keyword(s):  
Uric Acid ◽  
Flow Rate ◽  
Urine Flow ◽  
Urine Flow Rate ◽  
Acid Excretion ◽  
Uric Acid Excretion

scholarly journals Effect of pentose ingestion on uric acid excretion

1929 ◽  
Vol 23 (6) ◽  
pp. 1175-1177
Author(s):  
Kate Madders ◽  
Robert Alexander McCance
Keyword(s):  
Uric Acid ◽  
Acid Excretion ◽  
Uric Acid Excretion

scholarly journals POS1144 SERUM URIC ACID TO CREATININE RATIO IS ASSOCIATED WITH URINARY URIC ACID EXCRETION IN PATIENTS WITH GOUT

2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 851.2-851
Author(s):  
Z. Zhong ◽  
Y. Huang ◽  
X. Huang ◽  
Q. Huang ◽  
Y. Liu ◽  
...  
Keyword(s):  
Uric Acid ◽  
Serum Uric Acid ◽  
Acid Output ◽  
Area Under The Curve ◽  
Roc Curves ◽  
Binary Logistic Regression Analysis ◽  
Creatinine Ratio ◽  
Acid Excretion ◽  
Complete Collection ◽  
Uric Acid Excretion

Background:Underexcretion of uric acid is the dominant mechanism leading to hyperuricemia [1] and the 24-hour urinary uric acid excretion is an important measurement. However, it is inconvenient due to accurate timing and complete collection of the specimen.Objectives:The aim of this study was to investigate the relationship between serum uric acid to creatinine ratio (sUACR) and 24-hour urinary uric acid excretion in gout patients.Methods:A total of 110 gout patients fulfilling 2015 ACR/EULAR classification criteria from Guangdong Second Provincial General Hospital from January 2019 to January 2021 were retrospectively enrolled in this study. Patients were divided into underexcretion group (<3600 μmol/24h) and non-underexcretion group (≥3600 μmol/24h). The correlation between sUACR and 24-hour urinary uric acid excretion was analyzed by the Pearson’s correlations analysis. Receiver operation characteristic (ROC) curves were performed to assess the utility of sUACR for discriminating between underexcretion group and non-underexcretion group. Furthermore, the risk factors of uric acid underexcretion were evaluated using binary logistic regression analysis.Results:sUACR in the underexcretion group was significantly lower than the non-underexcretion group (p=0.0001). Besides, sUACR was positively correlated with 24-hour urinary uric acid excretion (r=0.4833, p<0.0001). Furthermore, ROC suggested that the area under the curve (AUC) of sUACR was 0.728, which was higher that of serum uric acid and creatinine. The optimal cutoff point of sUACR was 5.2312, with a sensitivity and specificity of 71.9% and 67.9%. Logistic analysis results revealed that decreased sUACR (<5.2312) was an independent risk factor of underexcretion of uric acid (OR =5.510, 95% CI: 1.952-15.550, P=0.001).Conclusion:sUACR is lower in gout patients with underexcretion of uric acid and may serve as a useful and convenient marker of assessing underexcretion of uric acid in gout patients.References:[1]Perez-Ruiz F, Calabozo M, Erauskin GG, Ruibal A, Herrero-Beites AM. Renal underexcretion of uric acid is present in patients with apparent high urinary uric acid output. Arthritis Rheum 2002; 47: 610–13.Figure 1.A. Comparison of serum uric acid to creatinine ratio between underexcretion group and non-underexcretion group. B. Correlation between serum uric acid to creatinine ratio and 24h uric acid excretion.Disclosure of Interests:None declared.

Uric acid excretion in normal children

1978 ◽  
Vol 92 (6) ◽  
pp. 911-914 ◽  
Author(s):  
F. Bruder Stapleton ◽  
Michael A. Linshaw ◽  
Khatab Hassanein ◽  
Alan B. Gruskin
Keyword(s):  
Uric Acid ◽  
Acid Excretion ◽  
Normal Children ◽  
Uric Acid Excretion

Uric acid excretion in infants and children

1971 ◽  
Vol 32 (3) ◽  
pp. 377-383 ◽  
Author(s):  
Helen K. Berry ◽  
Mary Granger
Keyword(s):  
Uric Acid ◽  
Infants And Children ◽  
Acid Excretion ◽  
Uric Acid Excretion ◽  
In Infants And Children

scholarly journals THE EFFECTIVENESS OF RENALOF® COMPARED TO KALKURENAL® AND PLACEBO

2012 ◽  
Vol 19 (2) ◽  
Author(s):  
Benny Kristyantoro ◽  
Sabilal Alif ◽  
Tarmono Djojodimedjo ◽  
Budiono Budiono
Keyword(s):  
Uric Acid ◽  
Surface Area ◽  
Renal Calculi ◽  
Renal Calculus ◽  
Renal Ultrasound ◽  
Acid Excretion ◽  
Stone Surface ◽  
Adjunct Therapy ◽  
Uric Acid Excretion ◽  
Plain Abdominal Film

Objective: To compare the effectiveness after administration of Renalof to Kalkurenal and placebo in patient with renal calculus. Material & Method: We analyzed 30 patient with renal calculi less than or equal to 20 mm (2 cm) between January 2011 and March 2011. Patients were divided into 3 groups. Nine patients were treated with placebo, 8 patients were treated with Kalkurenal and the last 13 patients were treated with Renalof. After 30 days, we analyzed calcium and uric acid excretion for 24 hours and measured the stone with plain abdominal film and renal ultrasound. Results: There were decreased in excretion of calcium and uric acid all of patients but not significant statistically (p > 0,05) and there were significant decreased on stone measurement in patient treated with Renalof. Conclusion: Renalof  can be given as adjunct therapy for patient with renal calculi. Keywords: Calcium and uric acid excretion in urine 24 hours, stone measurement and stone surface area.

scholarly journals Combined Supplementation with Glycine and Tryptophan Reduces Purine-Induced Serum Uric Acid Elevation by Accelerating Urinary Uric Acid Excretion: A Randomized, Single-Blind, Placebo-Controlled, Crossover Study

Nutrients ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 2562
Author(s):  
Oshima ◽  
Shiiya ◽  
Nakamura
Keyword(s):  
Uric Acid ◽  
Serum Uric Acid ◽  
Water Solubility ◽  
Elevated Serum ◽  
Acid Excretion ◽  
Japanese Adult ◽  
Urinary Ph ◽  
Uric Acid Excretion ◽  
Combined Supplementation ◽  
Single Blind

The authors previously confirmed the serum uric acid-lowering effects of the combination of glycine and tryptophan in subjects with mild hyperuricemia. This study examined whether combined supplementation with glycine and tryptophan suppressed the elevation in serum uric acid levels caused by purine ingestion and accelerated urinary uric acid excretion in subjects with lower urate excretion using a randomized, single-blind, placebo-controlled, crossover clinical trial design. Healthy Japanese adult males with lower urate excretion ingested water containing purines in addition to dextrin (placebo), tryptophan, glycine, or a glycine and tryptophan mixture. The combined supplementation with glycine and tryptophan significantly reduced the elevated serum uric acid levels after purine ingestion. Glycine alone and in combination with tryptophan significantly increased urinary uric acid excretion and urate clearance compared with the effects of the placebo. Urinary pH increased by the ingestion of the mixture. These results suggested that the improved water solubility of uric acid due to increased urinary pH contributed to the increase of urinary uric acid excretion.

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