Chemical Factors
Michael J. Kennish in Ecology of Estuaries Physical and Chemical Aspects, 2019
The three primary dissolved inorganic forms of nitrogen in estuaries are ammonia (NH3), nitrite (NO2−), and nitrate (NO3−), although dissolved organic and particulate forms also comprise useful and significant nitrogen sources. The principal dissolved inorganic form of phosphorus is the phosphate anion (PO43−), but dissolved organic and particulate forms are present and of considerable importance. Dissolved silicon occurs mainly as silicic acid (H4SiO4). The particulate forms of silicon are mainly detrital quartz and clay minerals (alumino silicates). A rather complex cycling of nitrogen, phosphorus, and silicon takes place in the estuarine environment and, because the cycling processes are not completely understood, they remain the subject of continuing research.
Nutritional Strategies for the Patient with Diabetic Nephropathy
Jeffrey I. Mechanick, Elise M. Brett in Nutritional Strategies for the Diabetic & Prediabetic Patient, 2006
An important part of secondary hyperparathyroidism is dietary phosphate restriction. Dairy products, cereals, grains, and colored-sodas are rich sources of dietary phosphate. Most of the drug therapies that treat hyperphosphatemia and secondary hyperparathyroidism act independently. Phosphate binders include calcium carbonate, calcium acetate, lanthanum carbonate, and sevelamer, whereas vitamin D and its analogs include calcitriol, paricalcitol, and doxercalciferol. Calcitriol may induce hypercalcemia and increase the calcium-phosphate cross-product. Moreover, hyperphosphatemia blunts the effects of vitamin D and its analogs. Cinacalcet offers the advantage of both reducing phosphate and PTH [103]. This calcimimetic agent mimics the effect of calcium on the receptor in the parathyroid cell to limit secretion and gene transcription of PTH. In stage-5 CKD patients, hyperphosphatemia often occurs despite adequate dialysis dose delivery [102]. Therefore, since protein intake necessarily includes phosphorus intake, coordinating the intake of these dietary constituents is essential.
Laboratory evaluation of parathyroid gland function
Pallavi Iyer, Herbert Chen in Thyroid and Parathyroid Disorders in Children, 2020
Phosphate is second to calcium in abundance; this anion is present in DNA and RNA nucleotides, essential for the generation of energy as adenosine triphosphate (ATP), and a component of cell membranes, signal transduction pathways, and the bone mineral—hydroxyapatite. It is absorbed by the intestinal duodenum and jejunum, filtered through the renal glomerulus to be reabsorbed by the proximal renal tubule or excreted in urine, and deposited into bone linked to calcium as hydroxyapatite from which site it may be reabsorbed by PTH and calcitriol. Under usual circumstances, the serum concentrations of calcium and phosphate are reciprocally related, and the calcium × phosphate product approximates 30. Serum concentrations of phosphate decrease with age: between 0 and 5 days serum phosphate levels range between 4.8 and 8.2 mg/dL; 1–3 years: 3.8–6.5 mg/dL; 4–11 years: 3.7–5.6 mg/dL; 12–15 years: 2.9–5.4 mg/dL; 16–19 years: 2.7–4.7 mg/dL; adult: 2.5–4.5 mg/dL.
Combined Administration of l -Carnitine and Ascorbic Acid Ameliorates Cisplatin-Induced Nephrotoxicity in Rats
Published in Journal of the American College of Nutrition, 2018
Quadri Kunle Alabi, Rufus Ojo Akomolafe, Olaoluwa Sesan Olukiran, Aliyat Olajumoke Nafiu, Modinat Adebukola Adefisayo, Olurotimi Isaac Owotomo, Joseph Gbenga Omole, Kehinde Peace Olamilosoye
The following electrolytes were measured in the plasma and urine: Na+, Cl−, K+, Ca2+, Mg2+, and PO43−. Na+ and K+ were measured by flame photometry using PFP7 (Jenway, Staffordshire, UK) flame photometer. Cl− was assayed according to the method of Skeggs and Hochstrasser (24), by using Teco laboratory kit (Anaheim, CA, USA). Ca2+ was measured using the cresolphthalein complexone method according to Burtis and Ashwood (25). Mg2+ was determined using a colorimetric assay kit according to the manufacturer's protocol (Sigma-Aldrich, St. Louis, MO, USA). PO43− was estimated by spectrophotometry method of complexing inorganic phosphate with ammonium molybdate at low pH.
Effect of curcumin nanoparticles on the cisplatin-induced neurotoxicity in rat
Published in Drug and Chemical Toxicology, 2019
Yasser A. Khadrawy, Mayada M. El-Gizawy, Safwa M. Sorour, Hussein G. Sawie, Eman N. Hosny
Total ATPase activity was assayed by adding 50 μl of the brain tissue homogenate to 2.5 ml of incubation medium consisting of 50 mM Tris-HCl (pH 7.4), 120 mM NaCl, 20 mM KCl, 4 mM MgCl2, 240 mM sucrose, 1 mM ethylenediamine tetraacetic acid, and 3 mM disodium ATP (substrate). After an incubation period of 10 min at 37 °C, the reaction was stopped by the addition of 50 μl ice cold trichloroacetic acid (30%). Then the mixture was centrifuged at 3000 rpm for 15 min. About 1 ml of the supernatant was added to 500 μl of 10% trichloroacetic acid, 250 μl ammonium molybdate (1%), and 250 μl ascorbic acid (20%) and used for the determination of the liberated inorganic phosphate (Pi). After 20 min at room temperature, the developed color was read at 640 nm against blank which contained 1500 μl of 10% trichloroacetic acid, 250 μl ammonium molybdate (1%), and 250 μl ascorbic acid (20%). The amount of liberated inorganic phosphate was quantified using KH2PO4 as a reference standard. The previous steps were repeated in the presence of 1 mM of ouabain (specific Na+/K+-ATPase inhibitor) in the incubation medium.
An update on phosphate binders for the treatment of hyperphosphatemia in chronic kidney disease patients on dialysis: a review of safety profiles
Published in Expert Opinion on Drug Safety, 2022
Hiroaki Ogata, Akiko Takeshima, Hidetoshi Ito
Hyperphosphatemia is an inevitable complication among patients with advanced chronic kidney disease (CKD) because impaired kidneys cannot excrete urinary phosphate commensurate to the dietary load [1,2]. Hyperphosphatemia is associated with various complications; therefore, nephrologists manage serum phosphate concentrations using restriction of dietary phosphorus intake, phosphate removal by dialysis, and drug therapy to ensure they stay within the optimal range. There is little evidence based on large-scale prospective cohorts or randomized control trials to know whether dietary intervention can improve clinical outcomes in CKD patients [3]. Strict restriction of dietary phosphate intake should not always be applied to all hyperphosphatemic patients [4]. Most foods inevitably contain phosphate; particularly, high-protein foods are rich in phosphate. Interestingly, the bioavailability of phosphate varies widely depending on foods [5]. In general, phosphate derived from meat, fish, and dairy products is likely to be absorbed in the gastrointestinal tract as compared with that from plants. Inorganic phosphate derived from food additives is thought to be absorbed almost completely. Therefore, in contrast to simply restricting the intake of phosphate or protein, the type of food might be more important in CKD patients with hyperphosphatemia.
Related Knowledge Centers
- Chemistry
- Ester
- Functional Group
- Phosphoric Acid
- Trisodium Phosphate
- Ion
- Salt
- Phosphoric Acids & Phosphates
- Ammonium Dihydrogen Phosphate
- Dihydrogen Phosphate