query: where does urea come from in the body

pos: Urea Urea Urea, also known as carbamide, is an organic compound with chemical formula CO(NH). This amide has two –NH groups joined by a carbonyl (C=O) functional group. Urea serves an important role in the metabolism of nitrogen-containing compounds by animals and is the main nitrogen-containing substance in the urine of mammals. It is a colorless, odorless solid, highly soluble in water, and practically non-toxic ( is 15 g/kg for rats). Dissolved in water, it is neither acidic nor alkaline. The body uses it in many processes, most notably nitrogen excretion. The liver forms it by combining two ammonia molecules (NH)

pos: Urea from ingested food that are not used for the synthesis of proteins and other biological substances — or produced from catabolism of muscle protein — are oxidized by the body as an alternative source of energy, yielding urea and carbon dioxide. The oxidation pathway starts with the removal of the amino group by a transaminase; the amino group is then fed into the urea cycle. The first step in the conversion of amino acids from protein into metabolic waste in the liver is removal of the alpha-amino nitrogen, which results in ammonia. Because ammonia is toxic, it is excreted immediately

pos: Protein (nutrient) process to individual amino acids, which are then absorbed. When amino acids are in excess of needs, the liver takes up the amino acids and deaminates them, a process converting the nitrogen from the amino acids into ammonia, further processed in the liver into urea via the urea cycle. Excretion of urea occurs via the kidneys. Other parts of the amino acid molecules can be converted into glucose and used for fuel. When food protein intake is periodically high or low, the body tries to keep protein levels at an equilibrium by using the "labile protein reserve" to compensate for

pos: Urea Urea Urea, also known as carbamide, is an organic compound with chemical formula CO(NH). This amide has two –NH groups joined by a carbonyl (C=O) functional group. Urea serves an important role in the metabolism of nitrogen-containing compounds by animals and is the main nitrogen-containing substance in the urine of mammals. It is a colorless, odorless solid, highly soluble in water, and practically non-toxic ( is 15 g/kg for rats). Dissolved in water, it is neither acidic nor alkaline. The body uses it in many processes, most notably nitrogen excretion. The liver forms it by combining two ammonia molecules (NH)

pos: Urea cycle aquatic organisms, or ammonotelic organisms, excrete ammonia without converting it. Ammonia is toxic, but upon excretion from aquatic species, it is diluted by the water outside the organism. Organisms that cannot easily and safely remove nitrogen as ammonia convert it to a less toxic substance such as urea or uric acid. The urea cycle mainly occurs in the liver. The urea produced by the liver is then released into the bloodstream where it travels to the kidneys and is ultimately excreted in urine. In species including birds and most insects, the ammonia is converted into uric acid or its urate

pos: Argininosuccinic aciduria cycle is a sequence of reactions in the cells of the liver. It processes excess nitrogen, generated when protein is used by the body, to make a compound called urea that is excreted by the kidneys. In argininosuccinic aciduria, the enzyme argininosuccinate lyase, involved in the conversion of arginino succinate to arginine within the urea cycle, is damaged or missing. The urea cycle cannot proceed normally, and nitrogen accumulates in the bloodstream in the form of ammonia. Ammonia is especially damaging to the nervous system, so argininosuccinic aciduria causes neurological problems as well as eventual damage to the liver. This

pos: Citrullinemia Citrullinemia Citrullinemia is an autosomal recessive urea cycle disorder that causes ammonia and other toxic substances to accumulate in the blood. Since the substances also accumulate in the urine, the disorder can also be called citrullinuria. Two forms of citrullinemia have been described, both having different signs and symptoms, and are caused by mutations in different genes. Citrullinemia belongs to a class of genetic diseases called urea cycle disorders. The urea cycle is a sequence of chemical reactions taking place in the liver. These reactions process excess nitrogen, generated when protein is used for energy by the body, to make

pos: Glutamic acid processes such as glycolysis, gluconeogenesis, and the citric acid cycle. Glutamate also plays an important role in the body's disposal of excess or waste nitrogen. Glutamate undergoes deamination, an oxidative reaction catalysed by glutamate dehydrogenase, as follows: Ammonia (as ammonium) is then excreted predominantly as urea, synthesised in the liver. Transamination can thus be linked to deamination, effectively allowing nitrogen from the amine groups of amino acids to be removed, via glutamate as an intermediate, and finally excreted from the body in the form of urea. Glutamate is also a neurotransmitter (see below), which makes it one of the most

pos: BUN-to-creatinine ratio infection, and by antianabolic drugs such as tetracyclines (except doxycycline) or glucocorticoids. It is decreased by low-protein diet, malnutrition or starvation, and by impaired metabolic activity in the liver due to parenchymal liver disease or, rarely, to congenital deficiency of urea cycle enzymes. The normal subject on a 70 g protein diet produces about 12 g of urea each day. This newly synthesized urea distributes throughout total body water. Some of it is recycled through the enterohepatic circulation. Usually, a small amount (less than 0.5 g/day) is lost through the gastrointestinal tract, lungs, and skin; during exercise, a substantial fraction

neg: Kt/V in mL or L. So the ratio of "K" × "t" / "V" is a so-called "dimensionless ratio" and can be thought of as a multiple of the volume of plasma cleared of urea divided by the distribution volume of urea. When Kt/V = 1.0, a volume of blood equal to the distribution volume of urea has been completely cleared of urea. The relationship between "Kt"/"V" and the concentration of urea "C" at the end of dialysis can be derived from the first-order differential equation that describes exponential decay and models the clearance of any substance from the body where

neg: Golding Bird thus played a large part in any treatment. The epitome of this kind of thinking was the concept of the vital force, which was supposed to govern the chemical processes within the body. This theory held that organic compounds could only be formed within living organisms, where the vital force could come into play. This belief had been known to be false ever since Friedrich Wöhler succeeded in synthesising urea from inorganic precursors in 1828. Nevertheless, the vital force continued to be invoked to explain organic chemistry in Bird's time. Sometime in the middle of the 19th century, a new

neg: Urea by fish, converted into uric acid by birds, and converted into urea by mammals. Ammonia (NH) is a common byproduct of the metabolism of nitrogenous compounds. Ammonia is smaller, more volatile and more mobile than urea. If allowed to accumulate, ammonia would raise the pH in cells to toxic levels. Therefore, many organisms convert ammonia to urea, even though this synthesis has a net energy cost. Being practically neutral and highly soluble in water, urea is a safe vehicle for the body to transport and excrete excess nitrogen. Urea is synthesized in the body of many organisms as part of

neg: Urine urea nitrogen Urine urea nitrogen Urine urea nitrogen (UUN) refers to a test that measures the urine urea to assess nitrogen balance. Urea nitrogen is the end product of breakdown of proteins in the body. In individuals with normal kidney and liver functions, urea is excreted via urine. By testing for UUN, clinicians can assess one's nitrogen balance. Calculating nitrogen balance is a useful tool in assessing adequacy of protein provision in clinical setting in: UUN is determined from 24-hour urine collection. Along with UUN, values for BUN, protein content of diet, enteral or parenteral nutrition, and notable outputs other than urine

neg: Standardized Kt/V concentration normalized by the mass generation per unit volume of body water. Equation "7" can be written in the following way: If one takes the inverse of Equation "8" it can be observed that the "inverse of std Kt/V" is proportional to the "concentration of urea" (in the body) divided by the "production of urea per time" per "unit volume of body water". Kt/V and "standardized Kt/V" are not the same. Kt/V is a ratio of the pre- and post-dialysis urea concentrations. Standardized Kt/V is an equivalent clearance defined by the initial urea concentration (compare equation "8" and equation "10").

neg: BUN-to-creatinine ratio are freely filtered by the glomerulus; however, urea reabsorbed by the tubules can be regulated (increased or decreased) whereas creatinine reabsorption remains the same (minimal reabsorption). Urea and creatinine are nitrogenous end products of metabolism. Urea is the primary metabolite derived from dietary protein and tissue protein turnover. Creatinine is the product of muscle creatine catabolism. Both are relatively small molecules (60 and 113 daltons, respectively) that distribute throughout total body water. In Europe, the whole urea molecule is assayed, whereas in the United States only the nitrogen component of urea (the blood or serum urea nitrogen, i.e., BUN or

neg: Carbamoyl phosphate synthetase I CPSI is genetics-based. Sometimes the body does not produce enough CPSI due to a mutation in the genetic code, resulting in poor metabolism of proteins and nitrogen, as well as high levels of ammonia in the body. This is dangerous because ammonia is highly toxic to the body, especially the nervous system, and can result in retardation and seizures. Carbamoyl phosphate synthetase I Carbamoyl phosphate synthetase I is a ligase enzyme located in the mitochondria involved in the production of urea. Carbamoyl phosphate synthetase I (CPS1 or CPSI) transfers an ammonia molecule from glutamine or glutamate to a molecule of

neg: Argininemia Argininemia Argininemia, also called arginase deficiency, is an autosomal recessive urea cycle disorder where a deficiency of the enzyme arginase causes a buildup of arginine and ammonia in the blood. Ammonia, which is formed when proteins are broken down in the body, is toxic if levels become too high; the nervous system is especially sensitive to the effects of excess ammonia. The presentation of argininemia, in those that are affected, is consistent with the following: Mutations in the "ARG1" gene cause argininemia, which belongs to a class of genetic diseases called urea cycle disorders. The urea cycle is a sequence

neg: Urea reduction ratio URR is closely related to Kt/V, and the two quantities can be derived from another with more or less precision, depending on the amount of additional information available about a given dialysis session. Kt/V is one of the reference methods by which the amount of dialysis given is measured. Kt/V, like the URR, focuses on urea as the target solute, and is based on the assumption that removal of urea is from a single space – "urea distribution volume", or formula_2 similar in capacity to the total body water. The urea distribution volume formula_2, although traditionally thought of as 60%

neg: Golding Bird him to be on the radical side of the debate, and he completely avoided whole-body arguments. Snow had found that the proportion of urea in the urine of his patients was low and concluded from this that urea was accumulating in the blood, and therefore proposed bloodletting to counter this. Bird disputed that increased urea in the blood was the cause of kidney disease and doubted the effectiveness of this treatment, citing the results of François Magendie, who had injected urea into the blood, apparently with no ill effects. It is not clear whether Bird accepted Snow's reasoning that urea

neg: Shark function to excrete large amounts of urea. When a shark dies, the urea is broken down to ammonia by bacteria, causing the dead body to gradually smell strongly of ammonia. Digestion can take a long time. The food moves from the mouth to a J-shaped stomach, where it is stored and initial digestion occurs. Unwanted items may never get past the stomach, and instead the shark either vomits or turns its stomachs inside out and ejects unwanted items from its mouth. One of the biggest differences between the digestive systems of sharks and mammals is that sharks have much shorter

neg: Urea reduction ratio A more accurate relationship between "URR" and "Kt/V" can be derived by single-pool, variable volume urea kinetic modeling. A simplified estimating equation also can be used. This gives results that are quite similar to formal urea modeling as long as dialysis treatments of 2–6 hours in duration are given, and Kt/V is between 0.7 and 2.0. formula_18 The formula_19 term is a function of the dialysis session duration (t), and adjusts for the amount of urea generated during the dialysis session. The second term, formula_20 adjusts for the additional urea that is cleared from the body through volume contraction. Because

neg: Renal urea handling Renal urea handling Renal urea handling is the part of renal physiology that deals with the reabsorption and secretion of urea. Movement of large amounts of urea across cell membranes is made possible by urea transporter proteins. Urea allows the kidneys to create hyperosmotic urine (urine that has more ions in it - is "more concentrated" - than that same person's blood plasma). Preventing the loss of water in this manner is important if the person's body must save water in order to maintain a suitable blood pressure or (more likely) in order to maintain a suitable concentration of sodium

neg: Nonvolatile acid Lactic acid is usually completely metabolized by the body, and is thus not excreted from the body. The following reactions result in nonvolatile acids: e.g. methionine or cysteine → Urea + CO + HSO → 2H + SO e.g. lysine or arginine →Urea + CO + HO + H HA → H + A Nonvolatile acid A nonvolatile acid (also known as a fixed acid or metabolic acid) is an acid produced in the body from sources other than carbon dioxide, and is not excreted by the lungs. They are produced from e.g. an incomplete metabolism of carbohydrates, fats, and

neg: Uremia these compounds can be toxic to the body. Uremic toxins are any biologically active compounds that are retained due to kidney impairment. Many uremic salts can also be uremic toxins. Urea was one of the first metabolites identified. Its removal is directly related to patient survival but its effect on the body is not yet clear. Still, it is not certain that the symptoms currently associated with uremia are actually caused by excess urea, as one study showed that uremic symptoms were relieved by initiation of dialysis, even when urea was added to the dialysate to maintain the blood urea

neg: Argininemia of reactions that occurs in liver cells(hepatocytes). This cycle processes excess nitrogen, generated when protein is used by the body, making urea that is excreted via the kidneys. The "ARG1" gene provides instructions for making an enzyme called arginase, this enzyme controls the last steps of the urea cycle, which produces urea by extracting nitrogen from arginine. In people with arginase deficiency, arginase is missing, and arginine is not broken down properly. consequently, urea cannot be produced and excess nitrogen accumulates in the blood in the form of ammonia. Ammonia and arginine are thought to cause neurological problems and other

neg: Urine urea nitrogen (gastric residual, fistula output, drainages) are needed to calculate nitrogen balance. Nitrogen Balance = Protein intake/6.25- (UUN/0.8+2.5 for every L output) * For average loss via sweat. As UUN test is based on 24-hour urine, in individuals with kidney disease with less than 1000 ml urine out/day or on dialysis, this test cannot be applied. Urine urea nitrogen Urine urea nitrogen (UUN) refers to a test that measures the urine urea to assess nitrogen balance. Urea nitrogen is the end product of breakdown of proteins in the body. In individuals with normal kidney and liver functions, urea is excreted via

neg: Polyurethane urea elastomer However, as of 2018, the PUU is still under development in the testing phase. Polyurethane urea elastomer The polyurethane urea elastomer (PUU), or poly(urethane urea) elastomer, is a flexible polymeric material that is composed of linkages made out of polyurethane and polyurea compounds. Due to its hyperelastic properties, it is capable of bouncing back high-speed ballistic projectiles as if the material had “hardened” upon impact. PUUs were developed by researchers from the U.S. Army Research Laboratory (ARL) and the Army’s Institute for Soldier Nanotechnology at the Massachusetts Institute of Technology (MIT) to potentially replace polyethylene materials in body armor and

neg: Polyurethane urea elastomer Polyurethane urea elastomer The polyurethane urea elastomer (PUU), or poly(urethane urea) elastomer, is a flexible polymeric material that is composed of linkages made out of polyurethane and polyurea compounds. Due to its hyperelastic properties, it is capable of bouncing back high-speed ballistic projectiles as if the material had “hardened” upon impact. PUUs were developed by researchers from the U.S. Army Research Laboratory (ARL) and the Army’s Institute for Soldier Nanotechnology at the Massachusetts Institute of Technology (MIT) to potentially replace polyethylene materials in body armor and other protective gear, such as combat helmets, face shields, and ballistic vests. In general,

neg: Ornithine nitrogen is added from aspartate, producing the denitrogenated fumarate, and the resulting arginine (a guanidinium compound) is hydrolysed back to ornithine, producing urea. The nitrogens of urea come from the ammonia and aspartate, and the nitrogen in ornithine remains intact. Ornithine is not an amino acid coded for by DNA, that is, not proteinogenic. However, in mammalian non-hepatic tissues, the main use of the urea cycle is in arginine biosynthesis, so, as an intermediate in metabolic processes, ornithine is quite important. Ornithine, via the action of ornithine decarboxylase (E.C. 4.1.1.17), is the starting point for the synthesis of polyamines such

neg: Kidney increase in urine concentration. The two factors work together to return the plasma osmolality to its normal levels. ADH binds to principal cells in the collecting duct that translocate aquaporins to the membrane, allowing water to leave the normally impermeable membrane and be reabsorbed into the body by the vasa recta, thus increasing the plasma volume of the body. There are two systems that create a hyperosmotic medulla and thus increase the body plasma volume: Urea recycling and the 'single effect.' Urea is usually excreted as a waste product from the kidneys. However, when plasma blood volume is low and

neg: Uremia of salt is impaired when salt intake is low or the vascular volume is inadequate. Acid excretion and nitrogenous metabolite excretion are impaired with the loss of kidney function. Urea was crystallized and identified between 1797 and 1808. Urea was hypothesized to be the source of urinary ammonia during this time and was confirmed in 1817. It was hypothesized that excess urea may lead to specific disorders. Later in 1821, it was confirmed that the body did produce urea and that it was excreted by the kidneys. In 1827, urea was first synthesized in the lab, confirming the composition of

neg: Urea reduction ratio of body weight, may actually be closer to 50% of the body weight in women and 55% in men with stage V (GFR < 15 ml/min) chronic kidney disease. The clearance of urea during the dialysis session formula_4 can be expressed in either formula_5 or formula_6. Time or formula_7 is the duration of the dialysis session, measured either in minutes or hours. So formula_8 is also a volume, either formula_9, or formula_10, and represents the volume of blood (in ml or L) cleared of urea during the dialysis session. Because formula_2 is also a volume, the ratio of formula_12 has

neg: Homocitrulline group longer than citrulline, but similar in structure. The metabolite is generated from a lysine residue after lysine reacts with cyanate. Cyanate is present in the human body in equilibrium with urea. Under physiological conditions the urea concentration may be too low to allow extensive carbamylation. However, the conversion process leading to the formation of homocitrulline from lysine in proteins is known to occur in vivo. During renal failure conditions, the urea concentration increases and carbamylation of many proteins can occur, which can be detected. It is believed that most carbamylation takes place during inflammation when the enzyme myeloperoxidase is

neg: Hyperolius nitidulus folds. During this period, since there is no food or water intake, the juvenile frog does not urinate or defecate. The body stores all nitrogenous waste as urea in body fluids and purines. As the hot weather increases the dorsal skin of the frog becomes white due to the presence iridophores that can reflect light like a mirror since they are filled with purines crystals. Juveniles are the only ones that survive a dry season because most adults cannot adapt to the changes in living condition and die. Juveniles born in the first 2/3 of the wet season have enough

neg: Wudu mark which other people will not have. You would come to me with a white blaze on your foreheads and white marks on your feet because of the traces of ablution." Abu Hurayra said, "I have heard prophet (may peace be upon him) say. In a believer adornment would reach the places where ablution reaches." Uthman ibn Affan stated that Muhammad, said, "He who performed ablution well, his sins would come out from his body, even coming out from under his nails." 'Umar ibn al-Khattab reported that Muhammad said, "No one among you does wuḍūʾ and does wuḍūʾ thoroughly –

neg: Kidd antigen system red blood cells approach the renal medulla (where there is a high concentration of urea), the urea transporter allows for rapid uptake of urea and prevents cell shrinkage in the hypertonic environment of the medulla. As the red cell leaves the medulla, the urea is transported back out of the cell, preventing cellular swelling and preventing the urea from being carried away from the kidney. HUT11 was detected on endothelial cells of the vasa recta (vascular supply of the renal medulla) but it is not present in renal tubules. Due to absence of the urea transporter, Jk(a-b-) cells are not

neg: Dakin oxidation Dakin oxidation. MTO forms a complex with hydrogen peroxide that increases the rate of addition of hydrogen peroxide to the carbonyl carbon. MTO does not, however, change the relative yields of phenol and phenyl carboxylic acid products. Mixing urea and hydrogen peroxide yields urea-hydrogen peroxide complex (UHC). Adding dry UHC to solventless phenyl aldehyde or ketone also accelerates Dakin oxidation. Like MTO, UHP increases the rate of nucleophilic addition of hydrogen peroxide. But unlike the MTO-catalyzed variant, the urea-catalyzed variant does not produce potentially toxic heavy metal waste; it has also been applied to the synthesis of amine oxides such

neg: Citrullinemia is the most common form of the disorder, affecting about one in 57,000 births worldwide. Mutations in the "ASS" gene cause type I citrullinemia. The enzyme made by this gene, argininosuccinate synthetase (), is responsible for one step of the urea cycle. Mutations in the "ASS" gene reduce the activity of the enzyme, which disrupts the urea cycle and prevents the body from processing nitrogen effectively. Excess nitrogen, in the form of ammonia, and other byproducts of the urea cycle, accumulate in the bloodstream, leading to the characteristic features of type I citrullinemia. The symptoms of type II citrullinemia (

neg: Fish physiology generally isotonic to their marine environments because of the high concentration of urea and trimethylamine N-oxide (TMAO), allowing them to be in osmotic balance with the seawater. This adaptation prevents most sharks from surviving in freshwater, and they are therefore confined to marine environments. A few exceptions exist, such as the bull shark, which has developed a way to change its kidney function to excrete large amounts of urea. When a shark dies, the urea is broken down to ammonia by bacteria, causing the dead body to gradually smell strongly of ammonia. Sharks have adopted a different, efficient mechanism to

neg: Dimethylol ethylene urea pressure applied to the fabric. This problem regarding the loss of tensile strength is common amongst cotton treatments. Currently, DMEU is used along with other formaldehyde urea derivatives for cotton fabrics of varying tear strength, color, softness, and ease of care. DMEU is a formaldehyde derivative and thus has been known to cause irritation of the skin and allergic reactions from those who are exposed to the resin for extended periods of time. DMEU is a mild irritant and if consumed in moderate quantities may have adverse effects on the body. Dimethylol ethylene urea Dimethylol ethyleneurea is an organic compound

neg: Ornithine translocase deficiency occurs in liver cells. This cycle processes excess nitrogen, generated when protein is used by the body, to make a compound called urea that is excreted by the kidneys. The "SLC25A15" gene provides instructions for making a protein called a mitochondrial ornithine transporter. This protein is needed to move a molecule called ornithine within the mitochondria (the energy-producing centers in cells). Specifically, this protein transports ornithine across the inner membrane of mitochondria to the region called the mitochondrial matrix, where it participates in the urea cycle. Mutations in the "SLC25A15" gene result in a mitochondrial ornithine transporter that is unstable

neg: Kt/V URR = 1 -"C"/"C". So 1-URR = "C"/"C". So by algebra, substituting into equation (4) above, since ln "C"/"C" = – ln "C"/"C", we get: Patient has a mass of 70 kg (154 lb) and gets a hemodialysis treatment that lasts 4 hours where the urea clearance is 215 mL/min. Therefore: This means that if you dialyze a patient to a Kt/V of 1.23, and measure the postdialysis and predialysis urea nitrogen levels in the blood, then calculate the URR, then -ln (1-URR) should be about 1.23. The math does not quite work out, and more complicated relationships have been

neg: Ornithine Ornithine Ornithine is a non-proteinogenic amino acid that plays a role in the urea cycle. Ornithine is abnormally accumulated in the body in ornithine transcarbamylase deficiency. The radical is ornithyl. -Ornithine is one of the products of the action of the enzyme arginase on -arginine, creating urea. Therefore, ornithine is a central part of the urea cycle, which allows for the disposal of excess nitrogen. Ornithine is recycled and, in a manner, is a catalyst. First, ammonia is converted into carbamoyl phosphate (). Ornithine is converted into a urea derivative at the δ (terminal) nitrogen by carbamoyl phosphate synthetase. Another

neg: Inorganic compound including organisms, which means that describing a chemical as inorganic does not obligately mean that it does not occur within living things. Friedrich Wöhler's conversion of ammonium cyanate into urea in 1828 is considered the starting point of modern organic chemistry. The Wöhler synthesis is of great historical significance because for the first time an organic compound (urea) was produced from inorganic precursors (the salt ammonium cyanate). This finding contradicted the then-mainstream theory vitalism, which stated that organic matter possessed a special force or "vital force" inherent to all things living. Prior to Wöhler's experiment, a sharp boundary was thought

neg: Arginase Arginase Arginase (, "arginine amidinase", "canavanase", "L-arginase", "arginine transamidinase") is a manganese-containing enzyme. The reaction catalyzed by this enzyme is: arginine + HO → ornithine + urea. It is the final enzyme of the urea cycle. It is ubiquitous to all domains of life. Arginase belong to the ureohydrolase family of enzymes. Arginase catalyzes the fifth and final step in the urea cycle, a series of biochemical reactions in mammals during which the body disposes of harmful ammonia. Specifically, arginase converts L-arginine into L-ornithine and urea. Mammalian arginase is active as a trimer, but some bacterial arginases are hexameric. The

neg: Osmoconformer isoosmotic with seawater, but their high osmolarity is maintained by making the concentration of organic solutes unnaturally high. Sharks concentrate urea in their body, and since urea denatures proteins at high concentrations, they also accumulate trimethylamine N-oxide (TMAO) to counter the effect. Sharks adjust their internal osmolarity according to the osmolarity of the sea water surrounding them. Rather than ingesting sea water in order to change their internal salinity, sharks are able to absorb sea water directly. This is due to the high concentration of urea kept inside their bodies. This high concentration of urea creates a diffusion gradient which

neg: Kt/V worked-out to account for the fluid removal (ultrafiltration) during dialysis as well as urea generation(see urea reduction ratio). Nevertheless, the URR and Kt/V are so closely related mathematically, that their predictive power has been shown to be no different in terms of prediction of patient outcomes in observational studies. The above analysis assumes that urea is removed from a single compartment during dialysis. In fact, this Kt/V is usually called the "single-pool" Kt/V. Due to the multiple compartments in the human body, a significant concentration rebound occurs following hemodialysis. Usually rebound lowers the Kt/V by about 15%. The amount of

neg: Aminoacylase or catabolized energy. Aminoacylase is involved in the regulation of the urea cycle. N-acetyl-L-glutamate is an allosteric activator of carbamoyl phosphate synthetase, a crucial enzyme that commits NH molecules to the urea cycle. The urea cycle gets rid of excess ammonia (NH) in the body, a process that must be up-regulated during times of increased protein catabolism, as amino acid breakdown produces large amounts of NH. When amino acid catabolism increases, N-Acetylglutamate synthase is up-regulated, producing more N-acetyl-L-glutamate, which up-regulates carbamoyl phosphate synthetase and allows it to dispose of the excess NH from catabolism. Aminoacylase is up-regulated during times of

neg: Ureas are readily alkylated by aldehydes. The products are α-hydroxyalkylureas. Formaldehyde gives the bis(hydroxymethyl)urea, an intermediate in the formation of urea-formaldehyde resins. Cyclic ureas result from glyoxal ((CHO)): Two equivalents of urea condense with isobutyraldehyde giving the alkylidene derivative: This derivative, isobutylidenediurea, is used as a slow-release fertilizer because in the soil it slowly hydrolyzes, reverting back to urea, an excellent source of fixed nitrogen. Ureas In chemistry, ureas are a class of organic compounds with the formula (RN)CO where R = H, alkyl, aryl, etc. Thus, in addition to describing a specific chemical compound (HN)CO), urea is the name of

neg: Urea-containing cream available over the counter. In the United Kingdom 100 g of 10% cream costs the NHS about 4.37 pounds. Urea cream is indicated for debridement and promotion of normal healing of skin areas with hyperkeratosis, particularly where healing is inhibited by local skin infection, skin necrosis, fibrinous or itching debris or eschar. Specific condition with hyperkeratosis where urea cream is useful include: Common side effects of urea cream are: In severe cases, there can be an allergic reaction with symptoms such as skin rash, urticaria, difficulty breathing and swelling of the mouth, face, lips, or tongue. Urea dissolves the intercellular

neg: Daharki Great SaintSACHO SATRAM is one of the biggest Temple in Pakistan, located in Raharki just 5 km away from Daharki Devotes from All over the Pakistan & other countries come here to visit throughout the year.Fair is also held once in a year. A gurdwara for Sikhs located at a little distance from Imam Bargah Daharki. Engro Fertilizer Plant is situated 2 kilometers in south region of Daharki city. Engro produces Engro Urea, Engro DAP, Engro NP, Engro Zarkhez, Zingro, Zorawar and Engro Envy. Engro Fertilizers is the largest urea producer in Pakistan. Daharki Daharki () is a city of

neg: Trinny & Susannah Undress the Nation are the 12 live manikins, standing by a list of the rules for their body shape. To end their body shape campaign, Trinny, Susannah and 100 women go to the hillside chalk carving, the Long Man of Wilmington, where Trinny parades a made over woman from each shape category. Meanwhile in the distance, Susannah organizes the others into changing the shape of the Long Man into a more feminine one by lying down in white boiler suits to give the symbol pigtails, hips and breasts. The event does not come without protest, where Pagans gather in an attempt to stop

neg: Sipitang of Indian company, Ballarpur Industries Limited. Generally, these activities does not directly benefit the locals. Most of the locals are involved in subsistence farming and fishing. The town is set to become one of Sabah's oil and gas industry centre following the state government's decision to build an oil and gas industrial park in Sipitang and the national oil company - Petronas's decision to build Sabah ammonia and urea plant in this town. The urea plant is planned to double Petronas's current total production capacity of urea to 2.6 million tonnes per annum (mtpa), while the ammonia plant will produce

neg: Argininosuccinate lyase Argininosuccinate lyase ASL (argininosuccinate lyase, also known as argininosuccinase) is an enzyme that catalyzes the reversible breakdown of argininosuccinate (ASA) producing the amino acid arginine and dicarboxylic acid fumarate. Located in liver cytosol, ASL is the fourth enzyme of the urea cycle and involved in the biosynthesis of arginine in all species and the production of urea in ureotelic species. Mutations in ASL, resulting low activity of the enzyme, increase levels of urea in the body and result in various side effects. The ASL gene is located on chromosome 7 between the centromere (junction of the long and short arm)

neg: Phenylacetylglutamine Phenylacetylglutamine Phenylacetylglutamine is a product formed by the conjugation of phenylacetate and glutamine. It is a common metabolite that is naturally occurring in human urine. The highly-nitrogenous compound most commonly encountered in the human subjects with urea cycle disorders, associated with uremic conditions in the body. These conditions, such as uremia or hyperammonemia, tend to cause high levels of nitrogen in the form of ammonia in the blood. Uremic conditions are a result of defects in enzymes that convert ammonia to urea, the primary nitrogenous waste metabolite in the urea cycle. Phenylacetylglutamine is the primary metabolite of the degradation of

neg: Ornithine acids to stimulate GH release by athletes is not recommended." -Ornithine -aspartate (LOLA), a stable salt of ornithine and aspartic acid, has been used in the treatment of cirrhosis. Ornithine Ornithine is a non-proteinogenic amino acid that plays a role in the urea cycle. Ornithine is abnormally accumulated in the body in ornithine transcarbamylase deficiency. The radical is ornithyl. -Ornithine is one of the products of the action of the enzyme arginase on -arginine, creating urea. Therefore, ornithine is a central part of the urea cycle, which allows for the disposal of excess nitrogen. Ornithine is recycled and, in a

neg: Urease use of urea is thought to promote eutrophication, despite the observation that urea is rapidly transformed by microbial ureases, and thus usually does not persist. Environmental urease activity is often measured as an indicator of the health of microbial communities. In the absence of plants, urease activity in soil is generally attributed to heterotrophic microorganisms, although it has been demonstrated that some chemoautotrophic ammonium oxidizing bacteria are capable of growth on urea as a sole source of carbon, nitrogen, and energy. By promoting the formation of calcium carbonate, ureases are potentially useful for biomineralization-inspired processes. Notably, micro-biologically induced formation of

neg: Urea of the loop of Henle, which makes the water reabsorb. By action of the urea transporter 2, some of this reabsorbed urea eventually flows back into the thin descending limb of the tubule, through the collecting ducts, and into the excreted urine. The body uses this mechanism, which is controlled by the antidiuretic hormone, to create hyperosmotic urine—i.e., urine with a higher concentration of dissolved substances than the blood plasma. This mechanism is important to prevent the loss of water, maintain blood pressure, and maintain a suitable concentration of sodium ions in the blood plasma. The equivalent nitrogen content (in

neg: Urease in mammals and humans which is considered to be very harmful to the mammals due to production of the toxic ammonia product in the mammalian cells. However, mammalian cells does not produce urease in fact, the source is the various bacterias in the body, specifically the intestine. European hare (Lepus europaeus),a class of Mammalia, was discovered to have high urease activity in their large intestine, a part of gastrointestinal tract. Previously, other mammals i.e. rats, pigs and rabbits, with postgastric fermentation were detected with lower urease activity compared to European Hare. In human kidneys, urea is present in order for

neg: Edmund Alexander Parkes Exercise on the Elimination of Nitrogen". He confirmed independently the observations of Adolf Eugen Fick and Johannes Wislicenus, against Justus Liebig's theory that muscular work implies the destruction of muscular tissue by oxidation. Parkes suggested that the elimination of urea is not dependent on the amount of muscular exercise, but on the consumption of nitrogenous food; and that muscular tissue does not consume itself as a fuel doing work. His experiments on the effects of alcohol on the human body (in which he was assisted by Cyprian Wollowicz) were in three papers (in 1870, 1872, and 1874), on the "Effects

neg: Aureoumbra lagunensis and benthic invertebrates. "A. lagunensis" thrives in low-light conditions, where it can maintain high growth rates at 150 umol photons m s, thus an increase in light attenuation causes a positive feedback which further perpetuates blooms. "A. lagunensis" nutrient uptake is unlike other common microalgae. It uptakes inorganic nitrogen in the form of ammonium (NH) and nitrite (NO) and organic nitrogen in the form of urea, but does not utilize nitrate (NO). It uses environment dissolved organic phosphorus as the sole source to regenerate phosphate for growth. The name "Aureoumbra lagunensis" is Latin derived, where ""Aureo"" comes from the word

neg: Glutaminase Glutaminase Glutaminase (, "glutaminase I", "L-glutaminase", "glutamine aminohydrolase") is an amidohydrolase enzyme that generates glutamate from glutamine. Glutaminase has tissue-specific isoenzymes. Glutaminase has an important role in glial cells. Glutaminase catalyzes the following reaction: Glutamine + HO → glutamate + NH Glutaminase is expressed and active in periportal hepatocytes, where it generates NH (ammonia) for urea synthesis, as does glutamate dehydrogenase. Glutaminase is also expressed in the epithelial cells of the renal tubules, where the produced ammonia is excreted as ammonium ions. This excretion of ammonium ions is an important mechanism of renal acid-base regulation. During chronic acidosis, glutaminase is

neg: N-Acetylglutamic acid N-Acetylglutamic acid N"-Acetylglutamic acid (also referred to as N"-Acetylglutamate, abbreviated NAG, chemical formula CHNO) is biosynthesized from glutamate and acetylornithine by ornithine acetyltransferase, and from glutamic acid and acetyl-CoA by the enzyme "N"-acetylglutamate synthase. The reverse reaction, hydrolysis of the acetyl group, is catalyzed by a specific hydrolase. It is the first intermediate involved in the biosynthesis of arginine in prokaryotes and simple eukaryotes and a regulator in the process known as the urea cycle that converts toxic ammonia to urea for excretion from the body in vertebrates. N-Acetylglutamic acid is an extracellular metabolite isolated from the prokaryote Rhizobium trifolii

neg: Pacific sleeper shark in frigid depths, the sleeper shark's liver oil does not contain squalene, which would solidify into a dense, nonbuoyant mass. Instead, the low-density compounds in the sharks' liver are diacylglyceryl ethers and triacylglycerol, which maintain their fluidity even at the lowest temperatures. Also, they store very little urea in their skin (like many deep sea sharks), but like other elasmobranchs, have high concentrations of urea and trimethylamine oxide (nitrogenous waste products) in their tissues as osmoprotectants and to increase their buoyancy. Trimethylamine oxide also serves to counteract the protein-destabilizing tendencies of urea and pressure. Its presence in the tissues of

neg: Papillary duct body at any given time. These processes are mediated by hormones (aldosterone, vasopressin) and the osmolarity (concentration of electrically charged chemicals) of the surrounding medulla. Hormones regulate how permeable the papillary duct is to water and electrolytes. In the medullary collecting duct specifically, vasopressin upregulates urea transporter A1. This increases the concentration of urea in the surrounding interstitium and increases the osmolarity. Osmolarity influences the strength of the force that pulls (reabsorbs) water from the papillary duct into the medullary interstitium. This is especially important in the papillary ducts. Osmolarity increases from the base of the renal pyramid to the

neg: Ornithine translocase deficiency Ornithine translocase deficiency Ornithine translocase deficiency, also called hyperornithinemia-hyperammonemia-homocitrullinuria (HHH) syndrome, is a rare autosomal recessive urea cycle disorder affecting the enzyme ornithine translocase, which causes ammonia to accumulate in the blood, a condition called hyperammonemia. Ammonia, which is formed when proteins are broken down in the body, is toxic if the levels become too high. The nervous system is especially sensitive to the effects of excess ammonia. Mutations in "SLC25A15" cause ornithine translocase deficiency. Ornithine translocase deficiency belongs to a class of metabolic disorders referred to as urea cycle disorders. The urea cycle is a sequence of reactions that

neg: Osmotherapy such as cerebral edema and ICP elevations upon withdrawal. Commonly used osmotic agents are urea, glycerol, mannitol and Hypertonic Saline. Dosage of osmotic agent administration is referred to as grams per person's body mass (g/ kg). Urea with σ=.59 was introduced in 1956 due to low molecular weight and slow penetration of BBB. However, it can cause rebound effects and side effects such as intravascular hemolysis and phlebitis. When Urea is administered, the dosage is 1.5 g/kg or 0.5 g/kg (for elderly). Glycerol with σ=.48 was introduced in 1964, but it has a likelihood of exhibiting rebound effects and causing

neg: Coated urea Another disadvantage has to do with the relatively large particle size of sulfur-coated urea fertilizers, which makes their use on closely mown surfaces like putting greens impractical. However, more recently, materials with smaller particle sizes have been developed, permitting the use of sulfur-coated ureas on putting greens. Polymer-coated urea, also called plastic-coated urea, or PCU, fertilizers can permit a more precise rate of nitrogen release than sulfur-coated urea products. It's possible to produce polymer-coated products where the nitrogen release can be delayed for 10 months after application. The primary disadvantage of polymer-coated urea products is their relatively high cost compared

neg: Azotemia and increase blood pressure, and the treatment of the condition that caused the azotemia. Azotemia Azotemia ("azot", "nitrogen" + "-emia", "blood condition") is a medical condition characterized by abnormally high levels of nitrogen-containing compounds (such as urea, creatinine, various body waste compounds, and other nitrogen-rich compounds) in the blood. It is largely related to insufficient or dysfunctional filtering of blood by the kidneys. It can lead to uremia and acute kidney injury (kidney failure) if not controlled. A urinalysis will typically show a decreased urine sodium level, a high urine creatinine-to-serum creatinine ratio, a high urine urea-to-serum urea ratio, and

neg: Azotemia Azotemia Azotemia ("azot", "nitrogen" + "-emia", "blood condition") is a medical condition characterized by abnormally high levels of nitrogen-containing compounds (such as urea, creatinine, various body waste compounds, and other nitrogen-rich compounds) in the blood. It is largely related to insufficient or dysfunctional filtering of blood by the kidneys. It can lead to uremia and acute kidney injury (kidney failure) if not controlled. A urinalysis will typically show a decreased urine sodium level, a high urine creatinine-to-serum creatinine ratio, a high urine urea-to-serum urea ratio, and concentrated urine (determined by osmolality and specific gravity). None of these is particularly useful

neg: Urea even spread. The application equipment must be correctly calibrated and properly used. Drilling must not occur on contact with or close to seed, due to the risk of germination damage. Urea dissolves in water for application as a spray or through irrigation systems. In grain and cotton crops, urea is often applied at the time of the last cultivation before planting. In high rainfall areas and on sandy soils (where nitrogen can be lost through leaching) and where good in-season rainfall is expected, urea can be side- or top-dressed during the growing season. Top-dressing is also popular on pasture and

neg: Urea as a byproduct from hydrocarbons (predominantly natural gas, less often petroleum derivatives), or occasionally from coal, urea production plants are almost always located adjacent to the site where the ammonia is manufactured. Although natural gas is both the most economical and the most widely available ammonia plant feedstock, plants using it do not produce quite as much carbon dioxide from the process as is needed to convert their entire ammonia output into urea. In recent years new technologies such as the KM-CDR process have been developed to recover supplementary carbon dioxide from the combustion exhaust gases produced in the fired

neg: Citrullinemia type I period. "ASS1" is the gene mutated in citrullinemia type I. Mutations in this gene have an autosomal recessive mode of inheritance. Arginosuccinate synthetase is an enzyme in the urea cycle, which removes excess ammonia from the body. When it is deficient, either fully or partially, ammonia can build up and cause the signs and symptoms of CTLN1. As one of the urea cycle disorders, citrullinemia type I needs to be distinguished from the others: carbamoyl phosphate synthetase deficiency, argininosuccinic acid lyase deficiency, ornithine transcarbamylase deficiency, arginase deficiency, and N-Acetylglutamate synthase deficiency. Other diseases that may appear similar to CTLN1 include

neg: Argininosuccinic aciduria or unusual body movements, or go into a coma. Complications from argininosuccinic aciduria may include developmental delay and mental retardation. Progressive liver damage, skin lesions, and brittle hair may also be seen. Immediate treatment and lifelong management (following a strict diet and using appropriate supplements) may prevent many of these complications. Occasionally, an individual may inherit a mild form of the disorder in which ammonia accumulates in the bloodstream only during periods of illness or other stress. Mutations in the ASL gene cause argininosuccinic aciduria. Argininosuccinic aciduria belongs to a class of genetic diseases called urea cycle disorders. The urea

neg: Great Basin spadefoot where it spends long periods during cold and dry weather. The toad is able to absorb water from the surrounding soil; even as the soil becomes increasingly dry in spring and early summer months, increased concentrations of urea in the toad's body allow it to continue to suck water out of the soil through osmosis. When the summer rains arrive the Great Basin spadefoot emerges from its burrow. Morphs and adult Great Basin spadefoots normally venture from their burrows at night, when it is rainy or the night air is humid enough for dew to collect. Captive spadefoots have been

neg: De Dana Dan kidnappers, but after all her customers decide to go on a strike, she agrees to pay the ransom. As Nitin does not want to go back to Kuljeet, they come up with a plan – they decide to get a dead body from Maamu and throw it onto the railway tracks, along with his driving licence, and then spread the news that the kidnappers have killed Nitin. Harbans' and Oberoi's families come to Pan Pacific Hotel, where the wedding is going to take place. Harbans and Oberoi click a photo to celebrate their families uniting. To give the advance money

neg: Amino acid encoded by stop codon and SECIS element. When taken up into the human body from the diet, the 20 standard amino acids either are used to synthesize proteins and other biomolecules or are oxidized to urea and carbon dioxide as a source of energy. The oxidation pathway starts with the removal of the amino group by a transaminase; the amino group is then fed into the urea cycle. The other product of transamidation is a keto acid that enters the citric acid cycle. Glucogenic amino acids can also be converted into glucose, through gluconeogenesis. Of the 20 standard amino acids,

neg: Somniosidae from fishing ships where the sharks were trapped in the fishing nets. The shark carcass is traditionally fermented in a shallow pit, with stones placed on top of the shark, allowing poisonous internal fluids, like urea and trimethylamine oxide, to be pressed and drained out of the body. The meat is then cured for several months, rendering it safe for human consumption. Somniosidae The Somniosidae are a family of sharks in the order Squaliformes, commonly known as sleeper sharks. The common name ""sleeper shark"" comes from their slow swimming, low activity level, and perceived non-aggressive nature. The Somniosidae can be

neg: Polyurea incomplete conversion to the amine-terminated polymer resins. The resin blend may also contain additives or non-primary components. These additives may contain hydroxyls, such as pre-dispersed pigments in a polyol carrier. Normally, the resin blend does not contain a catalyst(s). The word polyurea is derived from the Greek words πολυ- - poly- meaning "many"; and ουρίας - oûron meaning "to urinate" (referring to the substance urea, found in urine). Urea or carbamide is an organic compound with the chemical formula (NH)CO. The molecule has two amine groups (–NH) joined by a carbonyl functional group (C=O). In a polyurea, alternating monomer units

neg: Buddhism and euthanasia belief in compassion for all living things. A vegetative state can be considered a varied form of meditation where the sentience of someone acts in a way not ordinary to what is regularly observed. Another form of consciousness where the body does not react is that of "formless" rebirths. Due to these meditative states, it is often difficult to determine in a physical manner a state of consciousness. The state of consciousness, at the time, may be experiencing a demonstration of going through the processes of death in ultimate preparation so that once death does come, it can receive the

neg: Acute liver failure of urea, blood urea does not represent the degree of kidney impairment. About 60% of all ALF patients fulfil the criteria for systemic inflammatory syndrome irrespective of presence or absence of infection. This often contributes towards multi organ failure. Impaired host defence mechanism, due to impaired opsonization, chemotaxis and intracellular killing, substantially increases risk of sepsis. Bacterial sepsis mostly due to gram positive organisms and fungal sepsis are observed in up to 80% and 30% patients, respectively. Hyponatraemia is an almost universal finding due to water retention and a shift in intracellular sodium transport from inhibition of Na/K ATPase. Hypoglycaemia

neg: Winter service vehicle from salt mines, a non-renewable source. As a result, some road maintenance agencies have networks of ice prediction stations, to prevent unnecessary gritting which not only wastes salt, but can damage the environment and disrupt traffic. The US state of Oregon uses magnesium chloride, a relatively cheap chemical similar in snow-melting effects to sodium chloride, but less reactive, while New Zealand uses calcium magnesium acetate, which avoids the environmentally harmful chloride ion altogether. Urea is sometimes used to grit suspension bridges, as it does not corrode iron or steel at all, but urea is less effective than salt, and can

neg: Prashna Upanishad as life, as Agni (fire), as sun, as air, as space, as wind, as that which has form and as that which does not have form. The third Prashna of the Upanishad asks six questions: (1) Whence is life born? (2) when born, how does it come into the body? (3) when it has entered the body, how does it abide? (4) how does it go out of the body? (5) how does life interface its relation with nature and senses? (6) how does life interface with Self? Sage Pippalada states that these questions are difficult, and given the student's

neg: Urine Urine Urine is a liquid by-product of metabolism in humans and in many animals. Urine flows from the kidneys through the ureters to the urinary bladder. Urination results in urine being excreted from the body through the urethra. The cellular metabolism generates many by-products which are rich in nitrogen and must be cleared from the bloodstream, such as urea, uric acid, and creatinine. These by-products are expelled from the body during urination, which is the primary method for excreting water-soluble chemicals from the body. A urinalysis can detect nitrogenous wastes of the mammalian body. Urine has a role in the

neg: Blood urea nitrogen high orotic acid levels. BUN (urea-N) is mg/dL in the United States, Mexico, Italy, Austria, and Germany. Elsewhere, the concentration of urea is reported as mmol/L, generally depending on the lab. BUN (urea-N) SI unit is mmol/L BUN [mmol/L] = BUN [mg/dL] * 0.3571 To convert from mg/dL of blood urea nitrogen to mmol/L of urea, multiply by 0.357 (each molecule of urea having two nitrogens, each of molar mass 14g/mol) (BUN is the mass of nitrogen within urea/volume, not the mass of urea) convert BUN to urea in mg/dL by using following formula: factor = 1 for conversions in

neg: Alkali soil (HCl, HSO, etc.) can also be used to reduce the excess NaCO in the soil/water. Where urea is made available cheaply to farmers, it is also used to reduce the soil alkalinity / salinity primarily. The NH (Ammonium) present in urea which is a weak cation releases the strong cation Na from the soil structure into water. Thus alkali soils absorb / consume more urea compared to other soils. To reclaim the soils completely one needs prohibitively high doses of amendments. Most efforts are therefore directed to improving the top layer only (say the first 10 cm of the soils),

neg: Fauji Fertilizer Company of the Government of Pakistan. This acquisition at Rs. 8,151 million represents one of the largest industrial sector transactions in Pakistan. FFC now has three plants with a combined capacity of 5770 MTPD of prilled urea. Fauji Fertilizer Bin Qasim Limited (FFBL) is another company where FFC has controlling shares – it produces 1670 MTPD of granular urea plus 2250 MTPD DAP after revamping (1350 MTPD before revamp) DAP. Ammonia and urea plants capacity factors right from the plants start-up have been 100% or more. Today, FFC is also involved manpower training and turnaround services provider, especially within Pakistan and

neg: Gastrointestinal bleeding lower GI bleeds. Gastric aspiration and or lavage, where a tube is inserted into the stomach via the nose in an attempt to determine if there is blood in the stomach, if negative does not rule out an upper GI bleed but if positive is useful for ruling one in. Clots in the stool indicate a lower GI source while melana stools an upper one. Recommended laboratory blood testing includes: cross-matching blood, hemoglobin, hematocrit, platelets, coagulation time, and electrolytes. If the ratio of blood urea nitrogen to creatinine is greater than 30 the source is more likely from the upper

neg: Golden spiny mouse the mountains in southern Sinai where the temperature falls well below this threshold and there is often snow in the winter. "A. russatus" is also very good at conserving the little water it gets from its diet of insects and plants. It does this by producing extremely concentrated urine with urea content up to 4800 mM and chloride concentration up to 1500 mM. This means that it could survive drinking sea water, which is very rare in mammals. "Acomys russatus" is an opportunistic breeder that reaches sexual maturity at approximately 58 days of age. There is no mating season for

neg: Peptoid where proteolysis is a major issue. Since secondary structure in peptoids does not involve hydrogen bonding, it is not typically denatured by solvent, temperature, or chemical denaturants such as urea (see details below). Notably, since the amino portion of the amino acid results from the use of any amine, thousands of commercially available amines can be used to generate unprecedented chemical diversity at each position at costs far lower than would be required for similar peptides or peptidomimetics. To date, at least 230 different amines have been used as side chains in peptoids. Peptoid oligomers are known to be conformationally

neg: Urea are often used in horticultural crops. Low-biuret grades of urea are often indicated. Urea absorbs moisture from the atmosphere and therefore is typically stored either in closed or sealed bags on pallets or, if stored in bulk, under cover with a tarpaulin. As with most solid fertilizers, storage in a cool, dry, well-ventilated area is recommended. Overdose or placing urea near seed is harmful. Urea is a raw material for the manufacture of two main classes of materials: urea-formaldehyde resins and urea-melamine-formaldehyde used in marine plywood. Urea can be used to make urea nitrate, a high explosive that is used

neg: Pitcher plant and the body of it is gradually dissolved. This may occur by bacterial action (the bacteria being washed into the pitcher by rainfall) or by enzymes secreted by the plant itself. Furthermore, some pitcher plants contain mutualistic insect larvae, which feed on trapped prey, and whose excreta the plant absorbs. Whatever the mechanism of digestion, the prey items are converted into a solution of amino acids, peptides, phosphates, ammonium and urea, from which the plant obtains its mineral nutrition (particularly nitrogen and phosphorus). Like all carnivorous plants, they all grow in locations where the soil is too poor in minerals

neg: Urea reduction ratio formula_21 can be approximated by formula_22, where UF = ultrafiltrate removed during dialysis (estimated as the weight lost during the treatment) and W = postdialysis body weight, and because dialysis sessions given 3 times per week are usually about 3.5 hours long, the above equation can be simplified to: formula_23 Instead of equations, a nomogram can be used to easily estimate Kt/V from the URR in clinical practice. To use the nomogram, one needs to know the postdialysis weight (W) as well as the amount of weight (fluid) loss during the dialysis session (UF). First, find the URR on the

neg: Urea transporter Urea transporter A urea transporter is a membrane transport protein, transporting urea. Humans and other mammals have two types of urea transport proteins, UT-A and UT-B. The UT-A proteins are important for renal urea handling and are produced by alternative splicing of the SLC14A2 gene. Urea transport in the kidney is regulated by vasopressin. The structure of a urea transport family protein from "Desulfovibrio vulgaris" was determined by x-ray crystallography. The structure has a pathway through the membrane that is similar to that of ion channel proteins, accounting for the ability of urea transport proteins to move up to one

neg: Uremia nitrogen level at approximately 90 mg per deciliter (that is, approximately 32 mmol per liter). Urea could be the precursor of more toxic molecules but it is more likely that damage done to the body is from a combination of different compounds which may act as enzyme inhibitors or dereange membrane transport. Many regulatory functions of the body are affected. Regulation of body fluids, salt retention, acid and nitrogenous metabolite excretion are all impaired and can fluctuate widely. Body fluid regulation is impaired due to a failure to excrete fluids, or due to fluid loss from vomiting or diarrhea. Regulation

neg: Urea reduction ratio Urea reduction ratio The urea reduction ratio (URR), is a dimensionless number used to quantify dialysis treatment adequacy. formula_1 Where: Whereas the URR is formally defined as the urea reduction "ratio", in practice it is informally multiplied by 100% as shown in the formula above, and expressed as a percent. The URR was first popularized by Lowrie and Lew in 1991 as a method of measuring amount of dialysis that correlated with patient outcome. This method is very useful because of its simplicity. It permits easy monitoring of the amount of dialysis therapy delivered to individual patients, as well as

neg: Thermoset polymer matrix formed by copolymerisation of amines or amides with an aldehyde. Urea-formaldehyde and melamine-formaldehyde resins, although not widely used in high performance structural composite applications, are characteristically used as the polymer matrix in molding and extrusion compounds where some use of fillers and reinforcements occurs. Urea-formaldehyde resins are widely used as the matrix binder in construction utility products such as particle board, wafer board, and plywood, which are true particulate and laminar composite structures. Melamine-formaldehyde resins are used for plastic laminating. Furan resin prepolymers made from furfuryl alcohol, or by modification of furfural with phenol, formaldehyde, urea or other extenders, are

neg: Urea is a slow process (taking days to reach equilibrium), and freshly prepared, unheated solutions had negligible carbamylation rates. Urea reacts with alcohols to form urethanes. Urea reacts with malonic esters to make barbituric acids. "Urea" is New Latin from French "urée", from Ancient Greek οὖρον "ouron", "urine". Urea Urea, also known as carbamide, is an organic compound with chemical formula CO(NH). This amide has two –NH groups joined by a carbonyl (C=O) functional group. Urea serves an important role in the metabolism of nitrogen-containing compounds by animals and is the main nitrogen-containing substance in the urine of mammals. It is

neg: Urea reduction ratio be as large. Also minimally acceptable values for URR (and Kt/V) can be reduced in patients who have substantial amounts of residual renal function. Urea reduction ratio The urea reduction ratio (URR), is a dimensionless number used to quantify dialysis treatment adequacy. formula_1 Where: Whereas the URR is formally defined as the urea reduction "ratio", in practice it is informally multiplied by 100% as shown in the formula above, and expressed as a percent. The URR was first popularized by Lowrie and Lew in 1991 as a method of measuring amount of dialysis that correlated with patient outcome. This method

neg: Urea cycle cycle ingest amino acids beyond what is necessary for the minimum daily requirements the ammonia that is produced will not be able to be converted to urea. These individuals can experience hyperammonemia or the buildup of a cycle intermediate. Most urea cycle disorders are associated with hyperammonemia, however argininemia and some forms of argininosuccinic aciduria do not present with elevated ammonia. Urea cycle The urea cycle (also known as the ornithine cycle) is a cycle of biochemical reactions that produces urea ((NH)CO) from ammonia (NH). This cycle occurs in ureotelic organisms. The urea cycle converts highly toxic ammonia to urea

neg: Urea transporter million urea molecules per second across the membrane. Urea transporters can be inhibited by the action of urea analogues like thiourea and glycosides like phloretin. Their inhibition results in diuresis due to urea induced osmosis in the collecting ducts of the kidney. In mammals, there are two urea transporter genes: UT-A (SLC14A2) and UT-B (SLC14A1). Multiple protein isoforms derived from each gene are produced by alternative splicing and alternative promotors. Urea transporter A1 transports urea across the apical membrane into the intracellular space of luminal cells in the inner medullary collecting duct of the kidneys. UT-1 is activated by ADH,