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Published: 10 December 2022
Last updated: 28 January 2023

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1

Wright, P. A., G. K. Iwama, and C. M. Wood. "AMMONIA AND UREA EXCRETION IN LAHONTAN CUTTHROAT TROUT (ONCORHYNCHUS CLARKI HENSHAWI) ADAPTED TO THE HIGHLY ALKALINE PYRAMID LAKE (pH 9.4)." Journal of Experimental Biology 175, no. 1 (February 1, 1993): 153–72. http://dx.doi.org/10.1242/jeb.175.1.153.

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Earlier studies have reported that acute exposure to alkaline pH strongly inhibits ammonia excretion in freshwater rainbow trout, but the Lahontan cutthroat trout thrives in Pyramid Lake, Nevada, at pH 9.4. We investigated the rates and mechanisms of ammonia and urea excretion in this species in Pyramid Lake water to determine whether special strategies are employed to excrete nitrogenous wastes in an environment unfavourable for ammonia excretion. The majority of nitrogen wastes (N-wastes) were excreted as ammonia (56 % through the gills, 10 % through the kidney), while urea excretion accounted for 34 % (32 % gills, 2 % kidney). Ammonia excretion was dependent on the NH3 partial pressure gradient (deltaPNH3) across the gills and independent of Na+ influx and acidification of the gill water boundary layer. Acute exposure to more alkaline water (pH 10) decreased ammonia excretion by 52 %, while exposure to neutral water (pH 7.6) increased ammonia excretion by 200 %. When fish were held in a ‘closed system’ for 8 h, ammonia excretion decreased as water ammonia levels increased over the first 6 h. However, after 6 h a marked increase in ammonia excretion occurred which may have been associated with an increase in the PNH3 gradient and/or activation of a carrier-mediated transporter. We conclude that Lahontan cutthroat trout, adapted to pH 9.4 water, maintain N-waste excretion by modifying mechanisms common to other teleosts. These modifications include lower rates of ammonia excretion, a higher ratio of urea excretion to ammonia excretion, a higher rate of renal ammonia excretion, greater plasma pH and greater total ammonia level (increased plasma PNH3), which facilitate the diffusive excretion of NH3 across the gills, and a lack of dependence of ammonia excretion on Na+ influx.
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2

Kühnel, Christian, Falk Gühne, Philipp Seifert, Robert Freudenberg, Martin Freesmeyer, and Robert Drescher. "Transarterial Radioembolization Planning and Treatment with Microspheres Containing Holmium-166: Determination of Renal and Intestinal Radionuclide Elimination, Effective Half-Life, and Regulatory Aspects." Cancers 15, no. 1 (December 22, 2022): 68. http://dx.doi.org/10.3390/cancers15010068.

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After transarterial radioembolization (TARE) with microspheres loaded with holmium-166, radioactivity is excreted from the body. The aim of this study was to evaluate radioactive renal and intestinal excretions after TARE planning and treatment procedures with holmium-166-loaded microspheres and to correlate the findings with the intratherapeutic effective half-life. Urinary and intestinal excretions of patients who underwent TARE procedures were collected during postinterventional intervals of 24 h (TARE planning) and 48 h (TARE treatment). Whole-body effective half-life measurements were performed. Calibrations of the 166Ho measuring system showed evidence of long-living nuclides. For excretion determination, 22 TARE planning procedures and 29 TARE treatment procedures were evaluated. Mean/maximum total excretion proportions of the injected 166Ho were 0.0038%/0.0096% for TARE planning procedures and 0.0061%/0.0184% for TARE treatment procedures. The mean renal fractions of all measured excretions were 97.1% and 98.1%, respectively. Weak correlations were apparent between the injected and excreted activities (R2 planning/treatment: 0.11/0.32). Mean effective 166Ho half-lives of 24.03 h (planning) and 25.62 h (treatment) confirmed low excretions. Radioactive waste disposal regulations of selected jurisdictions can be met but must be reviewed before implementing this method into clinical practice. Inherent long-living nuclide impurities should be considered.
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3

Wood, C., T. Hopkins, C. Hogstrand, and P. Walsh. "Pulsatile urea excretion in the ureagenic toadfish Opsanus beta: an analysis of rates and routes." Journal of Experimental Biology 198, no. 8 (January 1, 1995): 1729–41. http://dx.doi.org/10.1242/jeb.198.8.1729.

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This study focused on the rates and routes of urea-N and ammonia-N excretion in the ureagenic toadfish and on the possibility that urea-N excretion occurs in pulses. Experimental approaches included the following: confinement in small individual containers with automated hourly sampling of water to follow temporal excretion patterns; divided chambers to separate excretion from the anterior and posterior parts of the fish; collection of urine and rectal fluid via chronic indwelling catheters; and gavage with [14C]-labelled polyethylene glycol 4000 to detect regurgitation of gastrointestinal fluids. When a standardized 'crowding' pre-treatment was employed to induce ureotelic behaviour, the fish exhibited significant elevations in the activity of glutamine synthetase in liver, kidney and gills, elevated plasma and bile urea-N levels, but unchanged ammonia-N and urea-N levels in most other body fluids. Unencumbered ureotelic fish confined in small containers excreted 82 % of their waste-N as urea-N and 18 % as ammonia-N; almost all (94 %) of this urea-N excretion occurred in a single pulse of less than 3 h duration about once every 24 h. This daily pulse did not occur by regurgitation of gut fluids, by excretion through prominent pores behind the pectoral fins or by discharge of rectal fluid or urine. Intestinal and urinary excretion accounted for less than 10 % of whole-body urea-N excretion and a negligible fraction of ammonia-N excretion. Pulsatile urea-N excretion occurred at the head end across the gills and/or body surface. Ammonia-N excretion, which was not pulsatile, also occurred largely through the head end. However, once the toadfish had been placed in divided chambers, urea-N excretion became continuous rather than pulsatile, and ammonia-N excretion increased greatly. A severe stress response was indicated by high levels of plasma cortisol, and the skin, which lacks scales, became a significant route of both ammonia-N and urea-N excretion. We speculate that the normal adaptive significance is that ureotelism facilitates cryptic behaviour, allowing the toadfish to virtually eliminate N-waste excretion during long periods while it remains sheltered in burrows. However, during severe stress, the effects of extremely high cortisol levels overwhelm the ammonia and urea retention mechanisms, and both substances leak across the general body surface.
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4

Legiawan, Mohamad Kany, and Dina Agustina. "Application of Augmented Reality Technology for Human Excretion System as Android-Based Learning Media." Media Jurnal Informatika 13, no. 1 (June 30, 2021): 17. http://dx.doi.org/10.35194/mji.v13i1.1488.

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The excretion system is a process of removing metabolic waste that is no longer used by the body. These remnants of metabolism in the form of compounds that are toxic (poison) so that if not removed can cause disruption of the function of organs in the body. Organs that play a role in the excretion system are the kidneys, lungs, skin and liver. Kidney is the main component making up the human excretion system, namely urine. The lungs produce residual respiratory processes in the form of gas CO2 (carbon dioxide) and H2O (water vapor). The skin is able to produce residual substances in the form of sweat. The liver produces waste products in the form of bile sap from an overhaul of red blood cells that have been damaged and destroyed in the spleen. Augmented Reality Human Excretion System is an application that can facilitate teachers and class XI MA Tanwiriyyah students in learning about the human excretion system. This application is made based on Android by applying augmented reality technology in its implementation. In this application the teacher and students can see 3D objects and know the process of removing residual substances in the excretory system organs. The design of this application uses the MDLC method and also uses UML diagrams, navigation structures and application interface design.
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5

Brauer, V. F. H., H. Below, A. Kramer, D. Führer, and R. Paschke. "The role of thiocyanate in the etiology of goiter in an industrial metropolitan area." European Journal of Endocrinology 154, no. 2 (February 2006): 229–35. http://dx.doi.org/10.1530/eje.1.02076.

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Objective: Thiocyanate (SCN−) has concentration dependent antithyroid properties and a role in the etiology of goiter has been suggested in several studies. In 1991 an epidemiological survey conducted in the region of Halle/Leipzig (Saxony), an area with significant air pollution, suggested an inverse relationship between urinary iodine (I−)/SCN− excretion and goiter prevalence. 10 years later, we reinvestigated the same industrial area to clarify if the situation has changed after the elimination of most industrial waste products and moreover, if SCN− excretion levels alone or in combination with air pollution or smoking as a SCN− source are critical for thyroid function. Design and methods: We investigated a cohort of 708 probands for I−, SCN− and creatinine excretion in spot urine samples and determined the prevalence of goiter and thyroid nodules by high resolution ultrasonography. Results: Probands with goiter (n = 79, 11%) had significantly higher urinary SCN− excretions than probands without (3.9 ± 2.8 vs 3.1 ± 3.4 mg SCN−/g creatinine) and significantly lower urinary I−/SCN− ratios than patients without thyroid disorders (41 ± 38 vs 61 ± 71 μg I−/mg SCN−/l). Mean urinary I− excretions were not different between probands with or without goiter. Smokers showed significantly elevated urinary SCN−/creatinine ratios in comparison to non-smokers (4.3 ± 4.3 vs 2.4 ± 2.1 mg SCN−/g creatinine). ANOVA revealed a prediction of thyroid volume through age (P < 0.001), gender (P < 0.001), body weight (P < 0.05) and smoking (P < 0.05). Conclusions: In our investigation, age, gender and smoking (raising SCN− levels by CN− inhalation) were predictive for thyroid volume and the urinary I−/SCN− ratios were able to detect probands with an increased risk of developing goiter in contrast to urinary I− excretion levels alone. These data suggest, that in an era and area of decreased cyanide pollution, SCN− may remain a cofactor in the multifactorial aetiology of goiter.
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6

Varley, D., and P. Greenaway. "NITROGENOUS EXCRETION IN THE TERRESTRIAL CARNIVOROUS CRAB GEOGRAPSUS GRAYI: SITE AND MECHANISM OF EXCRETION." Journal of Experimental Biology 190, no. 1 (May 1, 1994): 179–93. http://dx.doi.org/10.1242/jeb.190.1.179.

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The rate and mechanism of nitrogen excretion were examined in Geograpsus grayi. This species excretes waste nitrogen as gaseous NH3 in periodic bursts. The mean concentration of total ammonia ([NH3]+[NH4+]) in the primary urine during bursts of excretion (1.72 mmol l-1) was similar to that of haemolymph (2.07 mmol l-1) but was significantly lower (P&lt;0.005) than that of branchial fluid (80.6 mmol l-1). The effects of ion exchange inhibitors on the apical membrane of the gill epithelium in Geograpsus grayi were examined. The presence of an amiloride-sensitive Na+/NH4+ exchanger was confirmed and a SITS-sensitive Cl- influx suggested Cl-/HCO3- exchange. Thus, the site of nitrogenous excretion in this species is the branchial chamber, which is also the site of reprocessing of urine for ion regulation in other terrestrial crabs. Gaseous ammonia excretion is achieved by volatilisation of NH3 from the branchial fluid. High partial pressures of ammonia in the branchial fluid are produced by apical Na+/NH4+ exchange and elevation of the pH.
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7

Brusilow, Saul W. "Phenylacetylglutamine May Replace Urea as a Vehicle for Waste Nitrogen Excretion." Pediatric Research 29, no. 2 (February 1991): 147–50. http://dx.doi.org/10.1203/00006450-199102000-00009.

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8

Samson, Jaypee S. "Oral Administration of Pulverized Wood Charcoal on Growth, Feed Utilization, Survival and Waste Excretion of Red Tilapia Oreochromis Sp." International Journal of Trend in Scientific Research and Development Volume-3, Issue-4 (June 30, 2019): 417–21. http://dx.doi.org/10.31142/ijtsrd23724.

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9

WOOD, CHRIS M., R. G. BOUTILIER, and D. J. RANDALL. "The Physiology of Dehydration Stress in the Land Crab, Cardisoma Carnifex: Respiration, Ionoregulation, Acid-Base Balance and Nitrogenous Waste Excretion." Journal of Experimental Biology 126, no. 1 (November 1, 1986): 271–96. http://dx.doi.org/10.1242/jeb.126.1.271.

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Air-breathing Cardisoma carnifex, collected in Moorea, French Polynesia, were held in fresh water similar in chemical composition to that in their burrows. Under control conditions, which allowed branchial chamber flushing but not ventilation of the medium, crabs demonstrated net Na+ and Cl− uptake, and ammonia, urea and base excretion (= acidic equivalent uptake). Throughout 192 h of water deprivation, crabs dehydrated slowly at a rate of 0.55 g H2O kg−1 h−1, eventually reaching a near lethal 18% loss of total body water. Increases in haemolymph osmolytes were quite variable (0–29%); electrolyte excretion was negligible. MOO2 and MCOCO2 both decreased by approximately 55%, maintaining an unusually low gas exchange ratio (R = 0.53), and suggesting general metabolic depression. There was no evidence of internal hypoxia as haemolymph lactate remained at hydrated levels and PaOO2 actually increased. The dominant acid-base response was a progressive metabolic alkalosis accompanied by a partially compensating rise in PaCOCO2. Alkalosis was probably caused by blockage of the normal aquatic excretion of base produced by the metabolism of this herbivore. Other possible causes were eliminated: i.e. alkalaemia due to contraction of the ECFV; entrainment via strong ion shifts; CaCO3 mobilization; and ammonia accumulation in the haemolymph. In the absence of water, net ammonia production and excretion both appeared to cease, and alternate end products (urea, uric acid) did not generally accumulate. Within 2h of rehydration, crabs regained more than half the lost water, MOO2 and MCOCO2 increased above control levels, and ammonia excretion and haemolymph concentration both exhibited a prolonged (56 h) 4- to 6-fold rise. At the same time, metabolic alkalosis was reversed in association with elevated net base excretion into the water; the latter was correlated with an increase in the strong ion difference (SID) flux ([Na+ + K+ + Ca2+ + Mg2+ - Cl−]). Note:
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10

Gitelman, Hillel J. "Aluminum exposure and excretion." Science of The Total Environment 163, no. 1-3 (February 1995): 129–35. http://dx.doi.org/10.1016/0048-9697(95)04483-h.

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11

Wood, C., T. Hopkins, and P. Walsh. "Pulsatile urea excretion in the toadfish (Opsanus beta) is due to a pulsatile excretion mechanism, not a pulsatile production mechanism." Journal of Experimental Biology 200, no. 6 (March 1, 1997): 1039–46. http://dx.doi.org/10.1242/jeb.200.6.1039.

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When subjected to a crowding/confinement protocol in the laboratory, toadfish become facultatively ureotelic, excreting approximately 90 % of their nitrogenous waste as urea-nitrogen (urea-N). The great majority of this excretion occurs via large, irregular pulses from the head region which occur on average once per day, with a duration of 3 h or less. Pulses measured chemically by the appearance of urea-N in the external water were identical to those measured by assaying [14C]urea appearance in the water from the blood plasma. Individual toadfish maintained plasma urea concentrations over widely differing ranges (6600&shy;39 890 &micro;mol-N l-1). However, independent of absolute levels, both [14C]urea and total urea were distributed at ratios close to unity between the blood plasma and the water compartments of liver and white muscle. At times of pulsatile excretion, plasma urea concentration fell sharply. These decreases, distributed throughout the tissues of the whole body, closely matched the sizes of the measured excretion pulses. Between pulses, plasma urea concentration increased steadily at a much slower rate; the rate of rise, when distributed throughout the tissues of the whole body, corresponded to the time-averaged excretion rate over the whole day. Infusion of a typical pulse amount of urea immediately after the end of a natural pulse event raised plasma urea concentration slightly above the pre-pulse level, but did not induce another pulse event. Plasma cortisol levels declined by approximately 60 % over the 4 h period prior to a natural pulse event and then rose quickly again once the pulse had occurred. These results indicate that urea pulses are due to activation of an excretion mechanism that rapidly clears urea from the blood plasma, thereby lowering stores throughout the whole body. Metabolic production of urea is continuous and is not responsible for pulsatile excretion. The pulse event is not triggered by a specific plasma urea threshold, but may involve the hypothalamo&shy;interrenal axis.
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12

Sinclair, Martha, Felicity Roddick, Stephen Grist, Thang Nguyen, Joanne O'Toole, and Karin Leder. "Variability in 24 hour excretion of cyanuric acid: implications for water exposure assessment." Journal of Water and Health 14, no. 2 (October 30, 2015): 192–98. http://dx.doi.org/10.2166/wh.2015.230.

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Cyanuric acid (CYA) excretion in urine has been used to estimate the volume of water ingested during swimming and other recreational activities in outdoor pools containing this chemical. These estimates of water ingestion are based on the assumption of 100% excretion within 24 hours, but the supporting evidence for this is scant. While adapting this methodology to investigate other water ingestion scenarios, we observed a high degree of variability in cyanuric acid excretion among experimental subjects, with over 25% of individuals excreting less than 80% of an ingested dose. Use of cyanuric acid to measure inadvertent water ingestion may be a valuable tool to generate data for health risk assessment of non-potable water sources, but our observations indicate that this technique carries an inherent degree of underestimation that should be taken into account when calculating water exposure.
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13

Kaloyianni, Martha, and Maria Lazaridou-Dimitriadou. "Nitrogen excretion and the uricolytic enzymatic system in the nephridia and hepatopancreas of the snail Xeropicta arenosa." Canadian Journal of Zoology 67, no. 10 (October 1, 1989): 2473–77. http://dx.doi.org/10.1139/z89-349.

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The quantitative and qualitative examination of the uricolytic system in the nephridia and hepatopancreas of the terrestrial snail Xeropicta arenosa showed the presence of all the metabolites of uric acid catabolism, and examination of the metabolites of the uricolytic system in the snails waste products revealed that uric acid was the main nitrogenous waste product excreted. Correlation of excretion capability with the age of the snails revealed that (i) uric acid concentration was nine times higher in the waste products of the juveniles than in those of the old snails, (ii) urea was detectable only in waste products of old snails, (iii) traces of ammonia were detected in the waste products of snails of both ages, and (iv) the amount of allantoin present in the old snails' nephridia and heart was significantly higher than in those of the juveniles. On the other hand, all snails, regardless of age, stored most uric in the nephridia. Uric acid nitrogen represented 1% of the total nitrogen in the nephridia. Data from chemical analysis were confirmed by radiochemical analysis and showed the existence of the complete sequence of uricolytic catabolites in the snails' waste products and nephridia.
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14

Zhu, Songming, Brooks Saucier, James Durfey, Shulin Chen, and Bill Dewey. "Waste excretion characteristics of Manila clams (Tapes philippinarum) under different temperature conditions." Aquacultural Engineering 20, no. 4 (September 1999): 231–44. http://dx.doi.org/10.1016/s0144-8609(99)00015-1.

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15

Lam, Su Shiung, Mohd Azmi Ambak, Ahmad Jusoh, and Ah Theem Law. "Waste excretion of marble goby (Oxyeleotris marmorata Bleeker) fed with different diets." Aquaculture 274, no. 1 (January 2008): 49–56. http://dx.doi.org/10.1016/j.aquaculture.2007.11.023.

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16

Chipiga, L. A., A. V. Vodovatov, I. A. Zvonova, A. A. Stanzhevsky, A. V. Petryakova, E. E. Anokina, K. S. Velichkina, and S. A. Ryzhov. "Management of biological waste of patients after radionuclide therapy." Radiatsionnaya Gygiena = Radiation Hygiene 15, no. 2 (June 25, 2022): 19–30. http://dx.doi.org/10.21514/1998-426x-2022-15-2-19-30.

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Radioactive waste management is a modern-day issue in terms of radiation safety due to the development of radionuclide therapy, the emergence of new radiopharmaceuticals, radionuclides, and treatment methods, which allow for radionuclide therapy in a day hospital. According to the current domestic regulatory and methodological support biological wastes generated during the patient’s metabolic activity after injection of the radiopharmaceuticals for the therapy refer to the liquid radioactive waste. These wastes must be collected and kept for decay in hospitals to the safe levels before being spilled into the municipal sewerage. It requires additional expenses to the hospital for making the special sewerage. To increase the availability of radionuclide therapy, it is necessary to update the requirements of the liquid radioactive waste management in nuclear medicine departments, considering the volume activities of different diagnostic and therapeutic radionuclides in wastes generated after the injection of radiopharmaceuticals to the patients. On the basis of findings, it is possible to evaluate the feasibility of the binding requirement for the availability of special sewerage in the departments of the radionuclide therapy. In this work, excretion of the radiopharmaceuticals used in therapy: 89Sr-dichloride, 223Ra-dichloride, 131I-MIBG, 177Lu-PSMA, and 225Ac-PSMA was studied based on published data to determine the activity levels of radionuclides in waste of patients. As a results of preliminary computations, some nuclear medicine procedure will not lead to generation of liquid radioactive waste from biological waste of patients in sewerage system in usual operating condition and special sewerage is not strictly necessary. For example, estimations of radionuclide activity in wastes showed the volume of current sewerage system in a small hospital with a limitation of 50 beds can be enough to reduce the level of specific activity of radionuclides in wastewater from one patient a day after radionuclide therapy with 89Sr-chloride and 223Ra-dichloride. In order to revision of requirements to special sewerage in each department of radionuclide therapy and to development of differentiated approach to the management of biological waste of patient in nuclear medicine departments, which ensure environment protection and radiation safety of people, it is necessary to continue the research including development and modeling of realistic scenario of staff and patient radiation exposure confirmed experimental results.
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17

Wright, P. A. "Nitrogen excretion: three end products, many physiological roles." Journal of Experimental Biology 198, no. 2 (February 1, 1995): 273–81. http://dx.doi.org/10.1242/jeb.198.2.273.

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There are diverse physiological functions of nitrogen end products in different animal groups, including excretion, acid-base regulation, osmoregulation and buoyancy. Animals excrete a variety of nitrogen waste products, but ammonia, urea and uric acid predominate. A major factor in determining the mode of nitrogen excretion is the availability of water in the environment. Generally, aquatic animals excrete mostly ammonia, whereas terrestrial animals excrete either urea or uric acid. Ammonia, urea and uric acid are transported across cell membranes by different mechanisms corresponding to their different chemical properties in solution. Ammonia metabolism and excretion are linked to acid-base regulation in the kidney, but the role of urea and uric acid is less clear. Both invertebrates and vertebrates use nitrogen-containing organic compounds as intracellular osmolytes. In some marine invertebrates, NH4+ is sequestered in specific compartments to increase buoyancy.
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18

Walsh, P., and C. Milligan. "Effects of feeding and confinement on nitrogen metabolism and excretion in the gulf toadfish Opsanus beta." Journal of Experimental Biology 198, no. 7 (July 1, 1995): 1559–66. http://dx.doi.org/10.1242/jeb.198.7.1559.

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In order to elucidate further the cues for, and the biochemical mechanisms of, the transition to ureogenesis in the gulf toadfish Opsanus beta, experiments on the effects of feeding (i.e. nitrogen loading) were carried out. Baseline nitrogen excretion rates were first measured on solitary toadfish in large water volumes (i.e. unconfined conditions). These nitrogen excretion rates were higher, and had a higher proportion as ammonia (61 %), than previously published 'control' measurements. Feeding of unconfined toadfish elevated total nitrogen excretion approximately threefold, with little change in the proportion of urea versus ammonia. During the first 24 h of confinement of unfed toadfish, absolute levels of urea excretion remained constant while ammonia excretion rates fell to near zero, so that toadfish became 90 % ureotelic. When fed prior to confinement, urea excretion rates remained constant for the first 24 h, and the bulk of the nitrogen was excreted as ammonia (80 %); excretion of the excess dietary nitrogen took up to 48 h to complete. If pre-adapted to confinement and then fed, toadfish excreted only about 55 % of their nitrogenous waste as ammonia, and excretion of excess dietary nitrogen was completed by 24 h. Elevations of hepatic glutamine synthetase (GNS) activities accompanied confinement and were shown to be almost exclusively in the cytosolic compartment and to be correlated with a decrease in the ratio of hepatic levels of glutamate:glutamine. These GNS activity increases also appear to account in part for the decrease in the percentage of ammoniotely in toadfish under conditions of nitrogen loading after confinement. However, additional means of regulating total nitrogen excretion (e.g. changes in protein turnover rates) and the degree of ureogenesis versus ammoniogenesis (e.g. N-acetylglutamate stimulation of carbamoylphosphate synthetase) must be postulated to account fully for changes in nitrogen excretion rates and activation of ureogenesis under some circumstances.
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19

Milián-Sorribes, Maria Consolación, Ana Tomás-Vidal, David S. Peñaranda, Laura Carpintero, Juan S. Mesa, Javier Dupuy, Andrés Donadeu, Judit Macías-Vidal, and Silvia Martínez-Llorens. "Estimation of Phosphorus and Nitrogen Waste in Rainbow Trout (Oncorhynchus mykiss, Walbaum, 1792) Diets Including Different Inorganic Phosphorus Sources." Animals 11, no. 6 (June 7, 2021): 1700. http://dx.doi.org/10.3390/ani11061700.

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This study was conducted to evaluate the apparent availability and P and N excretion in rainbow trout (Oncorhynchus mykiss) using different inorganic phosphorus sources. With this goal, fish (153 ± 14.1 g) fed four inorganic P sources were assayed: monoammonium phosphate (MAP, NH4H2PO4), monosodium/monocalcium phosphate (SCP-2%, AQphos+, NaH2PO4/Ca(H2PO4)2·H2O in proportion 12/88), monosodium/monocalcium phosphate (SCP-5%, NaH2PO4/Ca(H2PO4)2·H2O in proportion 30/70) and monocalcium phosphate (MCP, Ca(H2PO4)2·H2O). Phosphorus (P) digestibility, in diets that included MAP and SCP-2% as inorganic phosphorus sources, were significantly higher than for SCP-5% and MCP sources. In relation to the P excretion pattern, independent of the diet, a peak at 6 h after feeding was registered, but at different levels depending on inorganic P sources. Fish fed an MAP diet excreted a higher amount of dissolved P in comparison with the rest of the inorganic P sources, although the total P losses were lower in MAP and SCP-2% (33.02% and 28.13, respectively) than in SCP-5% and MCP sources (43.35% and 47.83, respectively). Nitrogen (N) excretion was also studied, and the fish fed an SCP-5% diet provided lower values (15.8%) than MAP (28.0%). When N total wastes were calculated, SCP-2% and SCP-5% showed the lowest values (31.54 and 28.25%, respectively). In conclusion, based on P and N digestibility and excretion, the SCP-2% diet showed the best results from a nutritional and environmental point of view.
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20

Hamzah, Zainab, Sarojini Jeyaraman, Othman Hashim, and Kamarudin Hussin. "Waste to Wealth for the Edible Bird Nest Industry." Applied Mechanics and Materials 754-755 (April 2015): 990–97. http://dx.doi.org/10.4028/www.scientific.net/amm.754-755.990.

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Edible bird nest (EBN) is a product obtained from the salivary excretion of different species of swiftlets during the breeding season. It is an expensive health food product. The raw EBN needs intensive cleaning before it can be consumed. Currently, EBN is increasingly used in cosmetic products. The cleaning procedure generally produced about 30 % (w/w) of waste. To date, there is no work conducted to study the composition of the waste recovered from the cleaning process and converting the waste into useful downstream products. Therefore, the aim of this study is to determine the composition of the EBN wastes and to formulate a value added facial cream product from the EBN waste. EBN waste (residues) was collected from the cleaning water of EBN samples from the swiftlet species Aerodramusfuciphagus using the centrifugation method. The chemical composition of the EBN waste (residues) was analyzed qualitatively using the FTIR technique. Similarly, the different grades of processed EBN samples (2A, 3A, 4A, 5A and biscuit white) from the swiftlet species Aerodramusfuciphagus were quantitatively analyzed using the elemental analyzer. The residual EBN showed high protein content (47.33±3.09 %) and carbohydrate content of 2.4±0.37 %. Interestingly, nitrite, nitrate and lead were not present in the EBN waste. Thus, EBN waste is considered safe to formulate a facial cream. The collagen content in EBN is good as an anti-aging beauty cream. Since the EBN is a very expensive product, the residual EBN waste has good potential to formulate a value added product without any loss in its nutritional health benefits to achieve a similar effect as EBN. The high protein content retained in EBN waste makes the wash off water from EBN washings a suitable nutrient – rich component for the formulation of health and beauty products.
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Wood, C. M., P. Pärt, and P. A. Wright. "Ammonia and urea metabolism in relation to gill function and acid-base balance in a marine elasmobranch, the spiny dogfish (Squalus acanthias)." Journal of Experimental Biology 198, no. 7 (July 1, 1995): 1545–58. http://dx.doi.org/10.1242/jeb.198.7.1545.

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Nitrogenous waste excretion in resting dogfish occurred largely (&gt;90 %) as urea-nitrogen (urea-N) efflux across the gills, with a very small urea efflux via the kidney. Ammonia excretion, almost entirely at the gills, accounted for less than 3 % of total nitrogen excretion. Given the extremely high blood urea levels (approximately 640 mmol-N l-1) 'retained' for osmoregulation, and blood ammonia levels (approximately 80 &micro;mol-N l-1) comparable to those of teleosts, the gills of resting dogfish were exceptionally impermeable to both urea and ammonia. Experiments investigated the origins of these low permeabilities and the responses of urea-N and ammonia-N excretion and acid&shy;base status to 6 h infusions with iso-osmotic solutions of NaCl (control), NH4Cl, NaHCO3, urea and its analogues thiourea and acetamide. NaCl had no effects, whereas NH4Cl loading caused intense acidosis and marked elevation of acidic equivalent, ammonia-N and urea-N excretion rates, the latter despite unchanged blood levels of urea-N. Apparent branchial ammonia permeability increased greatly. Acidosis resulted from both stimulated urea production and branchial NH3 loss, the former making the larger contribution. NaHCO3 loading caused intense alkalosis, a marked elevation of basic equivalent excretion and a moderate stimulation of urea-N excretion. Blood urea-N levels were again unchanged. Infusion of urea itself raised blood urea-N levels, but initially reduced branchial urea-N excretion. Acetamide and thiourea infusions both moderately elevated branchial urea-N excretion. We suggest that the low ammonia permeability may arise metabolically from an ammonia scavenging system in the gills, that a 'back-transport' mechanism in the gills may contribute to the low urea permeability, and that the dissociation between blood urea-N levels and excretion rates may reflect urea production at extrahepatic sites. These studies demonstrate that urea synthesis in the dogfish is linked more to nitrogen availability than to acid&shy;base status.
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Morando, Michael B., Lea R. Medeiros, and M. Danielle McDonald. "Fluoxetine treatment affects nitrogen waste excretion and osmoregulation in a marine teleost fish." Aquatic Toxicology 93, no. 4 (July 2009): 253–60. http://dx.doi.org/10.1016/j.aquatox.2009.03.011.

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Morando, Michael B., Lea R. Medeiros, and M. Danielle McDonald. "Fluoxetine treatment affects nitrogen waste excretion and osmoregulation in a marine teleost fish." Aquatic Toxicology 95, no. 2 (November 2009): 164–71. http://dx.doi.org/10.1016/j.aquatox.2009.10.015.

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Moraes, G., and V. L. P. Polez. "Ureotelism is inducible in the neotropical freshwater Hoplias malabaricus (Teleostei, Erythrinidae)." Brazilian Journal of Biology 64, no. 2 (May 2004): 265–71. http://dx.doi.org/10.1590/s1519-69842004000200012.

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Increased environmental pH decreases ammonia transport through the gills, impairing nitrogenous waste. The consequent toxicity is usually drastic to most fishes. A few species are able to synthesize urea as a way to detoxify plasma ammonia. We studied three teleosts of the family Erythrinidae living in distinct environments, and assumed the biochemical behaviors would be different in spite of their being closely related species. Adult fish collected in the wild were submitted to alkaline water and the urea excretion rate was determined. The specific activity of urea cycle enzymes was determined in liver samples of fish from neutral waters. The studied species Hoplias lacerdae, Hoplerithrynus unitaeniatus, and Hoplias malabaricus are ureogenic. Urea synthesis is not a metabolic way to detoxify ammonia in H. lacerdae and Hoplerithrynus unitaeniatus exposed to an alkaline environment. The plasma ammonia profile of both species showed two distinct biochemical responses. Urea excretion of H. malabaricus was high in alkaline water, and the transition to ureotelism is proposed. The nitrogen excretion rate of H. malabaricus was among the highest values reported and the high urea excretion leads us to include this species as ureotelic in alkaline water.
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Pelster, Bernd, Chris M. Wood, Susana Braz-Mota, and Adalberto L. Val. "Gills and air-breathing organ in O2 uptake, CO2 excretion, N-waste excretion, and ionoregulation in small and large pirarucu (Arapaima gigas)." Journal of Comparative Physiology B 190, no. 5 (June 11, 2020): 569–83. http://dx.doi.org/10.1007/s00360-020-01286-1.

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Gottier Nwafor, Janine, Marta Nowik, Naohiko Anzai, Hitoshi Endou, and Carsten A. Wagner. "Metabolic Acidosis Alters Expression of Slc22 Transporters in Mouse Kidney." Kidney and Blood Pressure Research 45, no. 2 (2020): 263–74. http://dx.doi.org/10.1159/000506052.

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Introduction: The kidneys play a central role in eliminating metabolic waste products and drugs through transporter-mediated excretion along the proximal tubule. This task is mostly achieved through a variety of transporters from the solute carrier family 22 (SLC22) family of organic cation and anion transporters. Metabolic acidosis modulates metabolic and renal functions and also affects the clearance of metabolites and drugs from the body. We had previously shown that induction of metabolic acidosis in mice alters a large set of transcripts, among them also many transporters including transporters from the Slc22 family. Objective: Here we further investigated the impact of acidosis on Slc22 family members. Methods: Metabolic acidosis was induced for 2 or 7 days with NH4Cl, some animals also received the uricase inhibitor oxonic acid for comparison. Expression of transporters was studied by qPCR and immunoblotting. Results: NH4Cl induced no significant changes in plasma or urine uric acid levels but caused downregulation of Slc22a1 (Oct1), Slc22a6 (Oat1), Slc22a19 (Oat5), and ­Slc22a12 (Urat1) at mRNA level. In contrast, Slc22a4 mRNA (Octn1) was upregulated. On protein level, NH4Cl increased Octn1 (after 7 days) and Urat1 (after 2 days) abundance and decreased Oat1 (after 2 days) and Urat1 (after 7 days). Oxonic acid had no impact on protein abundance of any of the transporters tested. Conclusion: In summary, metabolic acidosis alters expression of several transporters involved in renal excretion of metabolic waste products and drugs. This may have implications for drug kinetics and clearance of waste metabolites.
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Duarte, Marcos Elias E., and Sung Woo Kim. "243 Nutritional Intervention for Reduced Nitrogen Excretion and Better Intestinal Health." Journal of Animal Science 100, Supplement_3 (September 21, 2022): 123–24. http://dx.doi.org/10.1093/jas/skac247.236.

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Abstract Increased awareness on public welfare has augmented the demand for more sustainable swine production. Nutritional interventions have been done to improve the dietary nitrogen utilization in order to reduce nitrogen excretion and enhance the intestinal health of pigs. Highly digestible protein supplements have been used as a strategy to enhance intestinal health and nitrogen utilization. Taking advantage of crystalline amino acids, low CP formulation with adequate amino acid supplementation has been used to reduce feed cost and improve intestinal health by decreasing protein fermentation. It has been estimated that reducing 1% protein in the diet reduces 9% nitrogen excretion and, consequently, environmental pollution. Feeding functional feed additives is another strategy to enhance intestinal health and nutrient digestion. Selected feed enzymes can reduce nitrogen excretion and improve intestinal health by directly increasing the digestibility of protein or by reducing antinutritional compounds such as allergenic proteins, phytate, and NSP that can impair protein digestion. Selected organic acids have antimicrobial properties and used in animal feeds to modulate intestinal microbiota, to enhance intestinal epithelial barrier function, and to improve protein digestibility. Selected prebiotics, probiotics, and postbiotics can reduce nitrogen excretion by changing the intestinal environment, enhancing the intestinal morphology, immune status, and the microbiota composition. Enhanced intestinal health with increased beneficial microbiota would increase the efficiency of nitrogen utilization consequently reducing nitrogen excretion. In summary, different nutritional strategies can be adopted to improve growth efficiency related to enhanced intestinal health and nutrient utilization, consequently reducing nitrogen excretion. Finally, improved feed efficiency and reduced nutrient waste would assure sustainable swine production, economic incentives to producers, and public welfare.
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Zandonà, Eugenia, Priscila Oliveira-Cunha, and Beatriz Moreira-Ferreira. "PAPEL DOS PEIXES NA RECICLAGEM DE NUTRIENTES EM RIACHOS TROPICAIS." Oecologia Australis 25, no. 02 (June 16, 2021): 449–63. http://dx.doi.org/10.4257/oeco.2021.2502.14.

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Fish can contribute directly and indirectly to nutrient recycling in aquatic environments, affecting community structure and ecosystem processes. Through the excretion of metabolic waste, fish make inorganic nutrients available in the environment that can be used by algae and bacteria. Nitrogen and phosphorus are often limiting nutrients in streams, so fish can be a relevant source of these nutrients. Many factors can influence excretion rates, including diet, body nutrient demand (for reproduction and growth), ontogeny, body size, temperature and other abiotic factors. Currently, two theories propose to explain which factors control excretion rates: 1) The Theory of Ecological Stoichiometry is based on mass balance models and uses the amount of nutrients in the diet and the fish nutrient demand as predictors of excretion rates; and 2) the Metabolic Theory of Ecology that uses body size and temperature as factors that regulate an organism metabolic rates and, thus, its excretion rates. The relative importance of fish as nutrient recyclers in streams varies depending on species intrinsic characteristics and environmental factors. This includes the magnitude of excretion rates from the entire fish community, the nutrient concentration and nutrient input into the stream, the stream nutrient demand and the period of activity and behavior of the fish. For example, species that are abundant in oligotrophic streams have the potential to represent an important source of nutrients. But other peculiarities, such as diet, specific nutrient demands, or migratory behaviors, can make them important sources or sinks of nutrients in a stream. This article reviews studies that address the role of fish as nutrient recyclers and explains the most common techniques used in this type of studies.
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T. C. Bridges, L. W. Turner, G. L. Cromwell, and J. L. Pierce. "Modeling the Effects of Diet Formulation on Nitrogen and Phosphorus Excretion in Swine Waste." Applied Engineering in Agriculture 11, no. 5 (1995): 731–39. http://dx.doi.org/10.13031/2013.25797.

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30

Simell, Olli, Ilkka Sipilä, Jukka Rajantie, David L. Valle, and Saul W. Brusilow. "Waste Nitrogen Excretion Via Amino Acid Acylation: Benzoate and Phenylacetate in Lysinuric Protein Intolerance." Pediatric Research 20, no. 11 (November 1986): 1117–21. http://dx.doi.org/10.1203/00006450-198611000-00011.

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31

BUCKING, CAROL, CHRISTOPHE M. R. LEMOINE, and PATRICK J. WALSH. "Waste Nitrogen Metabolism and Excretion in Zebrafish Embryos: Effects of Light, Ammonia, and Nicotinamide." Journal of Experimental Zoology Part A: Ecological Genetics and Physiology 319, no. 7 (June 10, 2013): 391–403. http://dx.doi.org/10.1002/jez.1802.

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32

Wilkie, M. P., Y. Wang, P. J. Walsh, and J. H. Youson. "Nitrogenous waste excretion by the larvae of a phylogenetically ancient vertebrate: the sea lamprey (Petromyzon marinus)." Canadian Journal of Zoology 77, no. 5 (October 1, 1999): 707–15. http://dx.doi.org/10.1139/z99-038.

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Larval sea lampreys (Petromyzon marinus) (ammocoetes) excreted significant quantities of urea, which composed 15-20% of the total nitrogenous waste excreted. Compared with teleosts of similar size, ammonia and urea excretion rates (JAmm and JUrea, respectively) in ammocoetes were relatively low, reflecting the low metabolic rate of these burrow-dwelling suspension feeders. Analyses of liver enzymes indicated that ammocoetes had all the enzymes necessary to produce urea via uricolysis, but not those of the ornithine-urea cycle (OUC). Further, exposure to 2 mmol·L-1 total ammonia for 5 d was accompanied by a 3-fold elevation of JUrea, but did not lead to greater OUC activity. Internal ammonia levels increased markedly, however, exceeding 2000 µmol·L-1 in plasma and 5000 µmol·L-1 in muscle after the 5-d exposure period. This high resistance to internal ammonia accumulation was related to the very high glutamine synthetase activities measured in ammocoete brains. The excretion and production of urea by ammocoetes demonstrates for the first time that agnathans are capable of producing physiologically relevant amounts of urea. Given the ancient origins and conserved evolution of lampreys, these observations also suggest that at least some of the early jawless vertebrates were able to produce and excrete urea.
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EKEHORN, GÖSTA. "V. Excretion of urinary waste-products under abnormal conditions, with special regard to tubular functions." Acta Medica Scandinavica 122, no. 2 (April 24, 2009): 134–69. http://dx.doi.org/10.1111/j.0954-6820.1945.tb04494.x.

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34

Wissel, Heiko, Thekla Wallbaum, Philipp Genseke, Dennis Kupitz, Jens Ricke, Juri Ruf, Holger Amthauer, and Oliver Stephan Großer. "Extraction of 223Radium by haemodialysis after treatment of metastatic castration-resistant prostate cancer." Nuklearmedizin 56, no. 03 (2017): 69–72. http://dx.doi.org/10.3413/nukmed-0874-16-12.

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Summary Aim: 223Radium-dichloride (223Ra) administration is an upcoming therapeutic option in patients with castration-resistant metastatic prostate cancer (mCRPC), whose renal and faecal excretion of 223Ra has been primarily estimated from data of a phase-I clinical trial in patients with normal renal function. In the rare case of concomitant renal insufficiency requiring haemodialysis (HD), an estimation of the contamination of dialysate would be beneficial. Methods: The excretion of 223Ra and its concentration in the dialysate in a patient with mCRPC and end-stage renal disease was examined for six consecutive treatment cycles. Dialysate samples were measured using a commercial system with NaI-scintillation detector. Results: HD showed a residual activity level in the remaining dialysate. The excreted activity was a median of 46.1 kBq (range = 42.0 83.4 kBq) and 11.2 kBq (range = 8.419.9 kBq) for the first (24 h post injection p.i.) and second HD (96 h p.i.), respectively. The activity concentration decreased significantly from a median of 4.18 kBq/l (range = 2.98-5.14 kBq/l) to 0.85 kBq/l (range=0.69-1.31 kBq/l, p < 0.0001). For all consecutive time points, the activity concentration further decreased significantly (p < 0.0001). The activity concentration of dialysate from HD performed 125.4 h p.i. [95 % confidence interval = 120.5-130.4 h p.i.] reached the threshold for unrestricted waste disposal. Conclusion: The observed extraction of 223Ra by HD exceeded the data determined from the phase-I study. The activity concentration in the dialysate observed for the first HD’s p.i. was above the threshold for unrestricted disposal of radioactive waste in Germany. Therefore, the specific requirement for waste handling has to be followed to fulfil the radiation protection regulations.
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Barber, M. L., and P. J. Walsh. "INTERACTIONS OF ACID-BASE STATUS AND NITROGEN EXCRETION AND METABOLISM IN THE UREOGENIC TELEOST OPSANUS BETA." Journal of Experimental Biology 185, no. 1 (December 1, 1993): 87–105. http://dx.doi.org/10.1242/jeb.185.1.87.

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The interactions of acid-base status, waste nitrogen excretion and metabolism in the gulf toadfish Opsanus beta, a ureogenic teleost, were examined by exposing toadfish to a variety of water treatments. Our measurements show that, like other marine teleosts, toadfish rapidly regulate acid- base status by manipulating blood [HCO3-]. Several treatments affected nitrogen excretion. The initial stages of hypercapnia (1 % CO2) led to significant reductions in ureogenesis, and the later compensated stages (with elevated plasma [HCO3-]) led to significant increases in ureogenesis. Treatment of water with HCl (which lowered pH and reduced the carbonate content) substantially inhibited ureogenesis. Subsequent experiments with NH4Cl loading and several other treatments suggest that this depression is less likely to be the result of acid-base perturbations, but is probably an enhancement of the fish's ability to excrete waste nitrogen as ammonia, thereby decreasing the drive for ureogenesis. Enzyme activities and hepatocyte ureogenic potential were unaffected by various acid-base treatments, but a significant depletion of plasma amino acid levels was associated with the increase in plasma [HCO3-] induced by hypercapnia. Changes in ureogenesis associated with our treatments appear to be due primarily to changes in substrate levels, rather than to wholesale changes of the biochemical machinery. Our results are discussed in the context of the hypothesis of Atkinson and colleagues, that ureogenesis is a means for acid-base regulation via bicarbonate consumption.
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Walsh, P. J., M. Grosell, G. G. Goss, H. L. Bergman, A. N. Bergman, P. Wilson, P. Laurent, et al. "Physiological and molecular characterization of urea transport by the gills of the Lake Magadi tilapia (Alcolapia grahami)." Journal of Experimental Biology 204, no. 3 (February 1, 2001): 509–20. http://dx.doi.org/10.1242/jeb.204.3.509.

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The Lake Magadi tilapia (Alcolapia grahami) is an unusual fish, excreting all its nitrogenous waste as urea because of its highly alkaline and buffered aquatic habitat. Here, using both physiological and molecular studies, we describe the mechanism of branchial urea excretion in this species. In vivo, repeated short-interval sampling revealed that urea excretion is continuous. The computed urea permeability of A. grahami gill is 4.74×10(−)(5)+/−0.38×10(−)(5)cm s(−)(1) (mean +/− s.e.m., N=11), some 10 times higher than passive permeability through a lipid bilayer and some five times higher than that of even the most urea-permeable teleosts studied to date (e.g. the gulf toadfish). Transport of urea was bidirectional, as demonstrated by experiments in which external [urea] was elevated. Furthermore, urea transport was inhibited by classic inhibitors of mammalian and piscine urea transporters in the order thiourea&gt;N-methylurea&gt;acetamide. A 1700 base pair cDNA for a putative Magadi tilapia urea transporter (mtUT) was cloned, sequenced and found to display high homology with urea transporters from mammals, amphibians and other fishes. When cRNA transcribed from mtUT cDNA was injected into Xenopus laevis oocytes, phloretin-inhibitable urea uptake was enhanced 3.4-fold relative to water-injected controls. Northern analysis of gill, red blood cells, liver, muscle and brain using a portion of mtUT as a probe revealed that gill is the only tissue in which mtUT RNA is expressed. Magadi tilapia gill pavement cells exhibited a trafficking of dense-cored vesicles between the well-developed Golgi cisternae and the apical membrane. The absence of this trafficking and the poor development of the Golgi system in a non-ureotelic relative (Oreochromis niloticus) suggest that vesicle trafficking could be related to urea excretion in Alcolapia grahami. Taken together, the above findings suggest that the gills of this alkaline-lake-adapted species excrete urea constitutively via the specific facilitated urea transporter mtUT.
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Weihrauch, Dirk, Andreas Ziegler, Dietrich Siebers, and David W. Towle. "Active ammonia excretion across the gills of the green shore crabCarcinus maenas: participation of Na+/K+-ATPase, V-type H+-ATPase and functional microtubules." Journal of Experimental Biology 205, no. 18 (September 15, 2002): 2765–75. http://dx.doi.org/10.1242/jeb.205.18.2765.

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SUMMARYAlthough aquatic animals are generally believed to export nitrogenous waste by diffusion of NH3 or NH4+ across external epithelia, evidence for active ammonia excretion has been found in a number of species. In the euryhaline green shore crab Carcinus maenas, active excretion of ammonia across isolated gills is reduced by inhibitors of the Na+/K+-ATPase and vacuolar-type H+-ATPase. In addition, a functional dynamic microtubule network is necessary, since application of colchicine, taxol or thiabendazole leads to almost complete blockage of active and gradient-driven ammonia excretion. Actin filaments seem not to play a role in the excretory process. The NH4+-dependent short-circuit current and the conductance of the isolated cuticle were reduced in a dose-dependent manner by amiloride,a non-specific inhibitor of the Na+/H+ exchanger and Na+ channels. Combined with an analysis of gill morphology, the strong intracellular but weak apical abundance of V-type H+-ATPase and the fact that ammonia flux rates are equal under buffered and unbuffered experimental conditions, our observations suggest a hypothetical model of transepithelial ammonia movement that features active uptake across the basolateral membrane, sequestration in acidified vesicles, vesicle transport via microtubules and exocytosis at the apical membrane.
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Serrano, María Jesús, Diego García-Gonzalo, Eunate Abilleira, Janire Elorduy, Olga Mitjana, María Victoria Falceto, Alicia Laborda, et al. "Antibacterial Residue Excretion via Urine as an Indicator for Therapeutical Treatment Choice and Farm Waste Treatment." Antibiotics 10, no. 7 (June 23, 2021): 762. http://dx.doi.org/10.3390/antibiotics10070762.

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Many of the infectious diseases that affect livestock have bacteria as etiological agents. Thus, therapy is based on antimicrobials that leave the animal’s tissues mainly via urine, reaching the environment through slurry and waste water. Once there, antimicrobial residues may lead to antibacterial resistance as well as toxicity for plants, animals, or humans. Hence, the objective was to describe the rate of antimicrobial excretion in urine in order to select the most appropriate molecule while reducing harmful effects. Thus, 62 pigs were treated with sulfamethoxypyridazine, oxytetracycline, and enrofloxacin. Urine was collected through the withdrawal period and analysed via LC-MS/MS. Oxytetracycline had the slowest rate of degradation (a half-life time of 4.18 days) and the most extended elimination period in urine (over 2 months), followed by enrofloxacin (a half-life time of 1.48 days, total urine elimination in ca. 3 weeks) and sulfamethoxypyridazine (a half-life time of 0.49 days, total urine elimination in ca. 1 week). Bacterial sensitivity and recommendations for responsible use are limiting when selecting the treatment. Nevertheless, with similar effectiveness, sulfamethoxypyridazine would be the choice, as waste treatment would only need to be implemented for 1 week after treatment. Thus, more in-depth knowledge regarding antibacterial elimination would improve resource management, while protecting animals and consumers’ health.
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Apollo, Michal. "Mountaineer’s Waste: Past, Present and Future." Annals of Valahia University of Targoviste, Geographical Series 16, no. 2 (October 1, 2016): 13–32. http://dx.doi.org/10.1515/avutgs-2016-0002.

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Abstract The growing number of mountaineers (climbers and trekkers) makes the problem of human waste amount to a considerable size (in tonnes of faeces and cubic metres of urine) of environmental degradation. Purity in the high mountains depends mainly on the mountaineers visiting them (the rule of ‘Leave No Trace’); however, if there is no assured suitable sanitation system, no mountaineer can be blamed for leaving human waste (faeces and urine), because the process of excretion cannot be stopped. The management can address the issue in three ways: complete (non–invasive), partial (superficial), and invasive. Those approaches have been elaborately explained in three case studies: Fuji–san (Japan), Yamunotri (India) and Kilimanjaro (Tanzania), respectively. Each of the places have been described based on the provided human waste disposal solutions, starting from the historical perspective and ending with the plans for future implementations, i.e. how it was, how it is, and how it will be. The results showed the improvement of understanding of the environmental pollution by human waste, at least from the management site. Decent changes have appeared in recent years–management bodies care more about human waste disposal. The authorities of mountain regions are gradually exchanging the old, leaking toilets for brand–new eco–friendly ones. Even if this process is slow–mostly because of economical limitations–management bodies appear to be noticing this threat. However, mountaineers do not always follow the implemented and recommended solution, as this study shows. The users should change their irresponsible behaviour, because even the best solutions in the case of human waste disposal in high–mountain conditions will fail if they do not follow the rules.
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SELIM, BASMA M., RANDA A. ABDELSALAM, ALAA EL-GINDY, BASMA G. EID, THIKRYAT NEAMATALLAH, AHDAB N. KHAYYAT, GHADA M. HADAD, and MAHMOUD M. ELKHOUDARY. "A green approach to the analysis of co-administered ampicillin/sulbactam and paracetamol in human urine." Acta Pharmaceutica 72, no. 2 (December 30, 2021): 259–74. http://dx.doi.org/10.2478/acph-2022-0015.

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Abstract The novelty of this work is the simultaneous analysis of sulbactam (SUL), ampicillin (AMP), and paracetamol (PARA) in human urine samples, using the environmentally benign RP-HPLC method. A C18 column was used in chromatographic separation using potassium dihydrogen phosphate (10 mmol L–1, pH 5)/ethanol (90 %, V/V) as the mobile phase; flow rate was 1.00 mL min–1. UV detection at 220 nm was used for quantification. The proposed method showed good linearity in the concentration ranges of 2.20–250.00 μg mL–1 for SUL, 2.50–250.00 μg mL–1 for PARA, and 14.50–250.00 μg mL–1 for AMP. Direct injection of urine samples with no prior extraction was performed. This method was found successful in moving towards greener studies of drugs’ urinary excretion, by decreasing hazardous solvent consumption and waste. Moreover, the method was applied to investigate the urinary excretion of the drugs and possible interaction between ampicillin and paracetamol.
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41

Gómez-Alarcón, G., M. L. Muñoz, and M. Flores. "Excretion of organic acids by fungal strains isolated from decayed sandstone." International Biodeterioration & Biodegradation 34, no. 2 (January 1994): 169–80. http://dx.doi.org/10.1016/0964-8305(94)90006-x.

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42

Eckerbom, Per, Peter Hansell, Eleanor Cox, Charlotte Buchanan, Jan Weis, Fredrik Palm, Susan Francis, and Per Liss. "Circadian variation in renal blood flow and kidney function in healthy volunteers monitored with noninvasive magnetic resonance imaging." American Journal of Physiology-Renal Physiology 319, no. 6 (December 1, 2020): F966—F978. http://dx.doi.org/10.1152/ajprenal.00311.2020.

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Circadian regulation of kidney function is involved in maintaining whole body homeostasis, and dysfunctional circadian rhythm can potentially be involved in disease development. Magnetic resonance imaging (MRI) provides reliable and reproducible repetitive estimates of kidney function noninvasively without the risk of adverse events associated with contrast agents and ionizing radiation. The purpose of this study was to estimate circadian variations in kidney function in healthy human subjects with MRI and to relate the findings to urinary excretions of electrolytes and markers of kidney function. Phase-contrast imaging, arterial spin labeling, and blood oxygen level-dependent transverse relaxation rate (R2*) mapping were used to assess total renal blood flow and regional perfusion as well as intrarenal oxygenation in eight female and eight male healthy volunteers every fourth hour during a 24-h period. Parallel with MRI scans, standard urinary and plasma parameters were quantified. Significant circadian variations of total renal blood flow were found over 24 h, with increasing flow from noon to midnight and decreasing flow during the night. In contrast, no circadian variation in intrarenal oxygenation was detected. Urinary excretions of electrolytes, osmotically active particles, creatinine, and urea all displayed circadian variations, peaking during the afternoon and evening hours. In conclusion, total renal blood flow and kidney function, as estimated from excretion of electrolytes and waste products, display profound circadian variations, whereas intrarenal oxygenation displays significantly less circadian variation.
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Takyi, Sylvia A., Niladri Basu, John Arko-Mensah, Duah Dwomoh, Afua Asabea Amoabeng Nti, Lawrencia Kwarteng, Augustine A. Acquah, Thomas G. Robins, and Julius N. Fobil. "Micronutrient Status of Electronic Waste Recyclers at Agbogbloshie, Ghana." International Journal of Environmental Research and Public Health 17, no. 24 (December 21, 2020): 9575. http://dx.doi.org/10.3390/ijerph17249575.

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Growing evidence suggests that micronutrient status is adversely impacted by toxic metals (e.g., cadmium, lead, and arsenic) exposures; however, the micronutrient status of e-waste recyclers who are amongst the highest metal-exposed groups is not known. This study, therefore, assessed the micronutrient status of e-waste recyclers using dietary information (2-day 24-h recall survey) and biomarker data (whole blood and urine) among 151 participants (100 e-waste recyclers at Agbogbloshie and 51 controls at Madina Zongo from the Accra region, Ghana) in March 2017. Biomarker levels of iron (Fe), calcium (Ca), magnesium (Mg), selenium (Se), zinc (Zn) and copper (Cu) were analyzed by the ICP-MS. Linear regression models were used to assess associations ofwork-related factors and sociodemographic characteristics with micronutrient intake, blood, and urine micronutrient levels. The results showed that apart from Fe and Zn, e-waste recyclers at Agbogbloshie did not meet the day-to-day dietary requirements for Ca, Cu, Se, and Mg intake. Except for the low levels of Mg and Fe detected in blood of e-waste recyclers, all other micronutrients measured in both blood and urine of both groups fell within their reference range. Exposure to biomass burning was associated with lower blood levels of Fe, Mg, and Zn among the e-waste recyclers. Further, among e-waste recyclers, significant relationships were found between the number of years spent recycling e-waste and urinary Ca and Cu excretion. Given that, some dietary and blood levels of micronutrients were below their reference ranges, the implementation of evidence-based nutrition strategies remains necessary among e-waste recyclers to reduce their risk of becoming malnourished.
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44

Lauff, R. F., and C. H. Wood. "Respiratory gas exchange, nitrogenous waste excretion, and fuel usage during aerobic swimming in juvenile rainbow trout." Journal Of Comparative Physiology B 166, no. 8 (December 1996): 501–9. http://dx.doi.org/10.1007/bf02338293.

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45

Lauff, R. F., and C. H. Wood. "Respiratory gas exchange, nitrogenous waste excretion, and fuel usage during aerobic swimming in juvenile rainbow trout." Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology 166, no. 8 (November 29, 1996): 501–9. http://dx.doi.org/10.1007/s003600050038.

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46

Zimmer, Alex M., and Chris M. Wood. "Physiological and molecular ontogeny of branchial and extra-branchial urea excretion in posthatch rainbow trout (Oncorhynchus mykiss)." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 310, no. 3 (February 1, 2016): R305—R312. http://dx.doi.org/10.1152/ajpregu.00403.2015.

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All teleost fish produce ammonia as a metabolic waste product. In embryos, ammonia excretion is limited by the chorion, and fish must detoxify ammonia by synthesizing urea via the ornithine urea cycle (OUC). Although urea is produced by embryos and larvae, urea excretion (Jurea) is typically low until yolk sac absorption, increasing thereafter. The aim of this study was to determine the physiological and molecular characteristics of Jurea by posthatch rainbow trout ( Oncorhynchus mykiss). Following hatch, whole body urea concentration decreased over time, while Jurea increased following yolk sac absorption. From 12 to 40 days posthatch (dph), extra-branchial routes of excretion accounted for the majority of Jurea, while the gills became the dominant site for Jurea only after 55 dph. This represents the most delayed branchial ontogeny of any process studied to date. Urea transporter (UT) gene expression in the gills and skin increased over development, consistent with increases in branchial and extra-branchial Jurea. Following exposure to 25 mmol/l urea, the accumulation and subsequent elimination of exogenous urea was much greater at 55 dph than 12 dph, consistent with increased UT expression. Notably, UT gene expression in the gills of 55 dph larvae increased in response to high urea. In summary, there is a clear increase in urea transport capacity over posthatch development, despite a decrease in OUC activity.
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47

Post, Adrian, Akin Ozyilmaz, Ralf Westerhuis, Karin Ipema, Stephan Bakker, and Casper Franssen. "Complementary Biomarker Assessment of Components Absorbed from Diet and Creatinine Excretion Rate Reflecting Muscle Mass in Dialysis Patients." Nutrients 10, no. 12 (November 26, 2018): 1827. http://dx.doi.org/10.3390/nu10121827.

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To prevent protein energy malnutrition (PEM) and accumulation of waste products, dialysis patients require diet adjustments. Dietary intake assessed by self-reported intakes often provides biased information and standard 24-h urinary excretion is inapplicable in dialysis patients. We aimed to assess dietary intake via a complementary, less biased biomarker method, and to compare this to dietary diaries. Additionally, we investigated the prospective association of creatinine excretion rate (CER) reflecting muscle mass with mortality. Complete intradialytic dialysate and interdialytic urinary collections were used to calculate 24-h excretion of protein, sodium, potassium, phosphate and creatinine in 42 chronic dialysis patients and compared with protein, sodium, potassium, and phosphate intake assessed by 5-day dietary diaries. Cox regression analyses were employed to investigate associations of CER with mortality. Mean age was 64 ± 13 years and 52% were male. Complementary biomarker assessed (CBA) and dietary assessed (DA) protein intake were significantly correlated (r = 0.610; p < 0.001), but there was a constant bias, as dietary diaries overestimated protein intake in most patients. Correlations were found between CBA and DA sodium intake (r = 0.297; p = 0.056), potassium intake (r = 0.312; p = 0.047) and phosphate uptake/intake (r = 0.409; p = 0.008). However, Bland-Altman analysis showed significant proportional bias. During a median follow-up of 26.6 (25.3–31.5) months, nine dialysis patients (23%) died. CER was independently and inversely associated with survival (HR: 0.59 (0.42–0.84); p = 0.003). Excretion measurements may be a more reliable assessment of dietary intake in dialysis patients, as this method is relatively free from biases known to exist for self-reported intakes. CER seems to be a promising tool for monitoring PEM.
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48

Chadwick, T. D., and P. A. Wright. "Nitrogen excretion and expression of urea cycle enzymes in the atlantic cod (Gadus morhua l.): a comparison of early life stages with adults." Journal of Experimental Biology 202, no. 19 (October 1, 1999): 2653–62. http://dx.doi.org/10.1242/jeb.202.19.2653.

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For many years, the urea cycle was considered to be relatively unimportant in the life history of most teleost fishes. In previous studies, we were surprised to find that newly hatched freshwater rainbow trout embryos had relatively high activities of the key urea cycle enzyme, carbamoyl phosphate synthetase III (CPSase III), and other enzymes in the pathway, whereas adult trout had much lower or non-detectable activities. The present study tested the hypothesis that urea cycle enzyme expression is unique to early stages of rainbow trout. In marine Atlantic cod (Gadus morhua) embryos, CPSase III, ornithine transcarbamoylase (OTCase), glutamine synthetase (GSase) and arginase activities were all expressed prior to hatching. Urea excretion was detected shortly after fertilization and rates were high relative to those of ammonia excretion (50–100 % of total nitrogen excreted as urea nitrogen; total=ammonia+urea). Urea concentration was relatively constant in embryos, but ammonia concentration increased by about fourfold during embryogenesis. Two populations of cod embryos were studied (from Newfoundland and New Brunswick), and significant differences in enzyme activities and excretion rates were detected between the two populations. In adult cod, CPSase III was not detectable in liver, white muscle, intestine and kidney tissues, but OTCase, GSase and arginase were present. Adult cod excreted about 17 % of nitrogenous waste as urea. Taken together, these data indicate that early urea cycle enzyme expression is not unique to rainbow trout but is also a feature of Atlantic cod development, and possibly other teleosts. The relatively high urea excretion rates underline the importance of urea as the primary nitrogen excretory product in Atlantic cod during early embryogenesis.
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49

Wood, Chris M., Bernd Pelster, Susana Braz-Mota, and Adalberto L. Val. "Gills versus kidney for ionoregulation in the obligate air-breathing Arapaima gigas, a fish with a kidney in its air-breathing organ." Journal of Experimental Biology 223, no. 20 (September 6, 2020): jeb232694. http://dx.doi.org/10.1242/jeb.232694.

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ABSTRACTIn Arapaima gigas, an obligate air-breather endemic to ion-poor Amazonian waters, a large complex kidney runs through the air-breathing organ (ABO). Previous indirect evidence suggested that the kidney, relative to the small gills, may be exceptionally important in ionoregulation and nitrogen (N) waste excretion, with support of kidney function by direct O2 supply from the airspace. We tested these ideas by continuous urine collection and gill flux measurements in ∼700 g fish. ATPase activities were many-fold greater in kidney than gills. In normoxia, gill Na+ influx and efflux were in balance, with net losses of Cl− and K+. Urine flow rate (UFR, ∼11 ml kg−1 h−1) and urinary ions (< 0.2 mmol l−1) were exceptional, with [urine]:[plasma] ratios of 0.02–0.002 for K+, Na+, and Cl−, indicating strong reabsorption with negligible urinary ion losses. Urinary [ammonia] was very high (10 mmol l−1, [urine]:[plasma] ∼17) indicating strong secretion. The kidney accounted for 21–24% of N excretion, with ammonia dominating (95%) over urea-N through both routes. High urinary [ammonia] was coupled to high urinary [HCO3−]. Aerial hypoxia (15.3 kPa) and aerial hyperoxia (>40.9 kPa) had no effects on UFR, but both inhibited branchial Na+ influx, revealing novel aspects of the osmorespiratory compromise. Aquatic hypoxia (4.1 kPa), but not aquatic hyperoxia (>40.9 kPa), inhibited gill Na+ influx, UFR and branchial and urinary ammonia excretion. We conclude that the kidney is more important than gills in ionoregulation, and is significant in N excretion. Although not definitive, our results do not indicate direct O2 supply from the ABO for kidney function.
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50

Neitzel, Richard L., Stephanie K. Sayler, Aubrey L. Arain, and Kowit Nambunmee. "Metal Levels, Genetic Instability, and Renal Markers in Electronic Waste Workers in Thailand." International Journal of Occupational and Environmental Medicine 11, no. 2 (March 31, 2020): 72–84. http://dx.doi.org/10.34172/ijoem.2020.1826.

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Background: Informal electronic waste (e-waste) recycling is an increasingly important industry worldwide. However, few studies have studied the health risks in this group of workers. Objective: To assess the associations between occupational exposures to metals and genetic instability and renal markers among e-waste recycling workers. Methods: We recruited informal e-waste recycling workers from a community in northeastern Thailand. Participants completed a questionnaire, several health measurements, and provided urine and blood samples, which we then analyzed for a number of metals including lead (Pb), cadmium (Cd), and manganese (Mn). Samples were analyzed for a marker of RNA and DNA damage (ie, oxidative stress), 8-hydroxy-2'-deoxyguanosine (8-OHdG). Glomerular filtration rate (GFR) and fractional excretion of calcium (FECa%) were measured as markers of renal function. Correlations and regression models were used to assess associations between these various factors. Results: We found significantly higher levels of Cd and Pb in blood of men compared with those in women. Men who worked >48 hours/week had significantly higher levels of 8-OHdG compared with men who worked ≤48 hours/week. Smoking was significantly associated with higher blood Pb and Cd concentrations among men. Conclusion: Our results suggest gender differences in both blood concentrations of metals associated with e-waste recycling and smoking and highlight potentially elevated oxidative stress associated with longer work hours. Health promotion efforts are needed among informal e-waste recyclers to reduce possible risks of renal damage and cancer
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