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Acidosis
Acidosis is a biological process producing hydrogen ions and increasing their concentration in blood or body fluids. pH is the negative log of hydrogen ion concentration and so it is decreased by a process of acidosis. Acidemia The term acidemia describes the state of low blood pH, when arterial pH falls below 7.35 (except in the fetus – see below) while ''acidosis'' is used to describe the processes leading to these states. The use of acidosis for a low pH creates an ambiguity in its meaning. The difference is important where a patient has factors causing both acidosis and alkalosis, wherein the relative severity of both determines whether the result is a high, low, or normal pH. Alkalemia occurs at a pH over 7.45. Arterial blood gas analysis and other tests are required to separate the main causes. In certain situations the main cause is clear. For instance, a diabetic with ketoacidosis is a recognizable case where the main cause of acidemia is essentially obvious. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diabetic Ketoacidosis
Diabetic ketoacidosis (DKA) is a potentially life-threatening acute complication of diabetes mellitus. Signs and symptoms may include vomiting, abdominal pain, deep gasping breathing, increased urination, weakness, confusion and occasionally loss of consciousness. A person's breath may develop a specific "fruity" or acetone smell. The onset of symptoms is usually rapid. People without a previous diagnosis of diabetes may develop DKA as the first obvious symptom. DKA happens most often in those with type 1 diabetes but can also occur in those with other types of diabetes under certain circumstances. Triggers may include infection, not taking insulin correctly, stroke and certain medications such as steroids. DKA results from a shortage of insulin; in response, the body switches to burning fatty acids, which produces acidic ketone bodies. DKA is typically diagnosed when testing finds high blood sugar, low blood pH and keto acids in either the blood or urine. The primary tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lactic Acidosis
Lactic acidosis refers to the process leading to the production of lactate by anaerobic metabolism. It increases hydrogen ion concentration tending to the state of acidemia or low pH. The result can be detected with high levels of lactate and low levels of bicarbonate. This is usually considered the result of illness but also results from strenuous exercise. The effect on pH is moderated by the presence of respiratory compensation. Lactic acidosis is usually the result of tissue hypoxia which is not the same as arterial hypoxia. Adequate circulation of blood and perfusion of metabolizing tissue to meet demand is necessary to prevent tissue hypoxia. Lactic acidosis can also be the result of illnesses, medications, poisonings or inborn errors of metabolism that interfere directly with oxygen utilization by cells. The symptoms are generally attributable to the underlying cause, but may include nausea, vomiting, shortness of breath, and generalised weakness. The diagnosis is made ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Renal Tubular Acidosis
Renal tubular acidosis (RTA) is a medical condition that involves an accumulation of acid in the body due to a failure of the kidneys to appropriately acidify the urine. In renal physiology, when blood is filtered by the kidney, the filtrate passes through the tubules of the nephron, allowing for exchange of salts, acid equivalents, and other solutes before it drains into the bladder as urine. The metabolic acidosis that results from RTA may be caused either by insufficient secretion of hydrogen ions (which are acidic) into the latter portions of the nephron (the distal tubule) or by failure to reabsorb sufficient bicarbonate ions (which are alkaline) from the filtrate in the early portion of the nephron (the proximal tubule). Although a metabolic acidosis also occurs in those with chronic kidney disease, the term RTA is reserved for individuals with poor urinary acidification in otherwise well-functioning kidneys. Several different types of RTA exist, which all have di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ketosis
Ketosis is a metabolic state characterized by elevated levels of ketone bodies in the blood or urine. Physiological ketosis is a normal response to low glucose availability. In physiological ketosis, ketones in the blood are elevated above baseline levels, but the body's acid–base homeostasis is maintained. This contrasts with ketoacidosis, an uncontrolled production of ketones that occurs in pathologic states and causes a metabolic acidosis, which is a medical emergency. Ketoacidosis is most commonly the result of complete insulin deficiency in type 1 diabetes or late-stage type 2 diabetes. Ketone levels can be measured in blood, urine or breath and are generally between 0.5 and 3.0 millimolar (mM) in physiological ketosis, while ketoacidosis may cause blood concentrations greater than 10 mM. Trace levels of ketones are always present in the blood and increase when blood glucose reserves are low and the liver shifts from primarily metabolizing carbohydrates to metabolizi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arterial Blood Gas
An arterial blood gas (ABG) test, or arterial blood gas analysis (ABGA) measures the amounts of arterial gases, such as oxygen and carbon dioxide. An ABG test requires that a small volume of blood be drawn from the radial artery with a syringe and a thin needle, but sometimes the femoral artery in the groin or another site is used. The blood can also be drawn from an arterial catheter. An ABG test measures the blood gas tension values of the arterial partial pressure of oxygen (PaO2), and the arterial partial pressure of carbon dioxide (PaCO2), and the blood's pH. In addition, the arterial oxygen saturation (SaO2) can be determined. Such information is vital when caring for patients with critical illnesses or respiratory disease. Therefore, the ABG test is one of the most common tests performed on patients in intensive-care units. In other levels of care, pulse oximetry plus transcutaneous carbon-dioxide measurement is a less invasive, alternative method of obtaining simila ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkalosis
Alkalosis is the result of a process reducing hydrogen ion concentration of arterial blood plasma (alkalemia). In contrast to acidemia (serum pH 7.35 or lower), alkalemia occurs when the serum pH is higher than normal (7.45 or higher). Alkalosis is usually divided into the categories of respiratory alkalosis and metabolic alkalosis or a combined respiratory/metabolic alkalosis. Signs and symptoms Metabolic alkalosis is usually accompanied by low blood potassium concentration, causing, e.g., muscular weakness, muscle pain, and muscle cramps (from disturbed function of the skeletal muscles), and muscle spasms (from disturbed function of smooth muscles). It may also cause low blood calcium concentration. As the blood pH increases, blood transport proteins, such as albumin, become more ionized into anions. This causes the free calcium present in blood to bind more strongly with albumin. If severe, it may cause tetany. Causes Respiratory alkalosis is caused by hyperventilati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Starvation
Starvation is a severe deficiency in caloric energy intake, below the level needed to maintain an organism's life. It is the most extreme form of malnutrition. In humans, prolonged starvation can cause permanent organ damage and eventually, death. The term ''inanition'' refers to the symptoms and effects of starvation. Starvation by outside forces is a crime according to international criminal law and may also be used as a means of torture or execution. According to the World Health Organization (WHO), hunger is the single gravest threat to the world's public health. The WHO also states that malnutrition is by far the biggest contributor to child mortality, present in half of all cases. Undernutrition is a contributory factor in the death of 3.1 million children under five every year. The results also demonstrates that as global hunger levels have stabilized, however, despite some progress in specific areas such as stunting and exclusive breastfeeding, an alarming number of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anaerobic Glycolysis
Anaerobic glycolysis is the transformation of glucose to lactate when limited amounts of oxygen (O2) are available. This occurs in health as in exercising and in disease as in sepsis and hemorrhagic shock. providing energy for a period ranging from 10 seconds to 2 minutes. During this time it can augment the energy produced by aerobic metabolism but is limited by the buildup of lactate. Rest eventually becomes necessary. The anaerobic glycolysis (lactic acid) system is dominant from about 10–30 seconds during a maximal effort. It produces 2 ATP molecules per glucose molecule, or about 5% of glucose's energy potential (38 ATP molecules). The speed at which ATP is produced is about 100 times that of oxidative phosphorylation. Anaerobic glycolysis is thought to have been the primary means of energy production in earlier organisms before oxygen was at high concentration in the atmosphere and thus would represent a more ancient form of energy production in cells. In mammals, lac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bicarbonate
In inorganic chemistry, bicarbonate (IUPAC-recommended nomenclature: hydrogencarbonate) is an intermediate form in the deprotonation of carbonic acid. It is a polyatomic anion with the chemical formula . Bicarbonate serves a crucial biochemical role in the physiological pH buffering system. The term "bicarbonate" was coined in 1814 by the English chemist William Hyde Wollaston. The name lives on as a trivial name. Chemical properties The bicarbonate ion (hydrogencarbonate ion) is an anion with the empirical formula and a molecular mass of 61.01 daltons; it consists of one central carbon atom surrounded by three oxygen atoms in a trigonal planar arrangement, with a hydrogen atom attached to one of the oxygens. It is isoelectronic with nitric acid (). The bicarbonate ion carries a negative one formal charge and is an amphiprotic species which has both acidic and basic properties. It is both the conjugate base of carbonic acid (); and the conjugate acid of , t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methanol
Methanol (also called methyl alcohol and wood spirit, amongst other names) is an organic chemical compound and the simplest aliphatic Alcohol (chemistry), alcohol, with the chemical formula (a methyl group linked to a hydroxyl group, often abbreviated as MeOH). It is a light, Volatility (chemistry), volatile, colorless and flammable liquid with a distinctive alcoholic odor similar to that of ethanol (potable alcohol), but is more acutely toxic than the latter. Methanol acquired the name wood alcohol because it was once produced through destructive distillation of wood. Today, methanol is mainly produced industrially by hydrogenation of carbon monoxide. Methanol consists of a methyl group linked to a polar hydroxyl group. With more than 20 million tons produced annually, it is used as a Precursor (chemistry), precursor to other commodity chemicals, including formaldehyde, acetic acid, methyl tert-butyl ether, methyl ''tert''-butyl ether, methyl benzoate, anisole, peroxyacids, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron
Iron is a chemical element; it has symbol Fe () and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, forming much of Earth's outer and inner core. It is the fourth most abundant element in the Earth's crust, being mainly deposited by meteorites in its metallic state. Extracting usable metal from iron ores requires kilns or furnaces capable of reaching , about 500 °C (900 °F) higher than that required to smelt copper. Humans started to master that process in Eurasia during the 2nd millennium BC and the use of iron tools and weapons began to displace copper alloys – in some regions, only around 1200 BC. That event is considered the transition from the Bronze Age to the Iron Age. In the modern world, iron alloys, such as steel, stainless steel, cast iron and special steels, are by far the most common industrial metals, due to their mechan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycolysis
Glycolysis is the metabolic pathway that converts glucose () into pyruvic acid, pyruvate and, in most organisms, occurs in the liquid part of cells (the cytosol). The Thermodynamic free energy, free energy released in this process is used to form the high-energy molecules adenosine triphosphate (ATP) and NADH, reduced nicotinamide adenine dinucleotide (NADH). Glycolysis is a sequence of ten reactions catalyzed by enzymes. The wide occurrence of glycolysis in other species indicates that it is an ancient metabolic pathway. Indeed, the reactions that make up glycolysis and its parallel pathway, the pentose phosphate pathway, can occur in the Great Oxygenation Event, oxygen-free conditions of the Archean oceans, also in the absence of enzymes, catalyzed by metal ions, meaning this is a plausible prebiotic pathway for abiogenesis. The most common type of glycolysis is the ''Embden–Meyerhof–Parnas (EMP) pathway'', which was discovered by Gustav Embden, Otto Meyerhof, and Jakub Kar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
