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Refeeding Syndrome
Refeeding syndrome is a metabolic disturbance that occurs as a result of reinstitution of nutrition in people and animals who are starved, severely malnourished, or metabolically stressed because of severe illness. When too much food or liquid nutrition supplement is eaten during the initial four to seven days following a malnutrition event, the production of glycogen, fat and protein in cells may cause low serum concentrations of potassium, magnesium and phosphate. Cardiac, pulmonary and neurological symptoms can be signs of refeeding syndrome. The low serum minerals, if severe enough, can be fatal. Cause Any individual who has had a negligible nutrient intake for many consecutive days and/or is metabolically stressed from a critical illness or major surgery is at risk of refeeding syndrome. Refeeding syndrome usually occurs within four days of starting to re-feed. Patients can develop fluid and electrolyte imbalance, especially hypophosphatemia, along with neurologic, pulmonary, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gastroenterology
Gastroenterology (from the Greek gastḗr- “belly”, -énteron “intestine”, and -logía "study of") is the branch of medicine focused on the digestive system and its disorders. The digestive system consists of the gastrointestinal tract, sometimes referred to as the ''GI tract,'' which includes the esophagus, stomach, small intestine and large intestine as well as the accessory organs of digestion which includes the pancreas, gallbladder, and liver. The digestive system functions to move material through the GI tract via peristalsis, break down that material via digestion, absorb nutrients for use throughout the body, and remove waste from the body via defecation. Physicians who specialize in the medical specialty of gastroenterology are called gastroenterologists or sometimes ''GI doctors''. Some of the most common conditions managed by gastroenterologists include gastroesophageal reflux disease, gastrointestinal bleeding, irritable bowel syndrome, irritable bowel dise ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypophosphatemia
Hypophosphatemia is an electrolyte disorder in which there is a low level of phosphate in the blood. Symptoms may include weakness, trouble breathing, and loss of appetite. Complications may include seizures, coma, rhabdomyolysis, or softening of the bones. Causes include alcohol use disorder, refeeding in those with malnutrition, recovery from diabetic ketoacidosis, burns, hyperventilation, and certain medications. It may also occur in the setting of hyperparathyroidism, hypothyroidism, and Cushing syndrome. It is diagnosed based on a blood phosphate concentration of less than 0.81 mmol/L (2.5 mg/dL). When levels are below 0.32 mmol/L (1.0 mg/dL) it is deemed to be severe. Treatment depends on the underlying cause. Phosphate may be given by mouth or by injection into a vein. Hypophosphatemia occurs in about 2% of people within hospital and 70% of people in the intensive care unit (ICU). Signs and symptoms * Muscle dysfunction and weakness – This occurs in major muscles ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2,3-diphosphoglycerate
2,3-Bisphosphoglyceric acid (conjugate acid, conjugate base 2,3-bisphosphoglycerate) (2,3-BPG), also known as 2,3-diphosphoglyceric acid (conjugate base 2,3-diphosphoglycerate) (2,3-DPG), is a three-carbon isomer of the glycolytic intermediate 1,3-Bisphosphoglyceric acid, 1,3-bisphosphoglyceric acid (1,3-BPG). -2,3-BPG is present in human red blood cells (RBC; erythrocyte) at approximately 5 mmol/L. It binds with greater affinity to deoxygenated hemoglobin (e.g., when the red blood cell is near respiring tissue) than it does to oxygenated hemoglobin (e.g., in the lungs) due to conformational differences: 2,3-BPG (with an estimated size of about 9 Ångström, Å) fits in the deoxygenated hemoglobin conformation (with an 11-Angstrom pocket), but not as well in the oxygenated conformation (5 Angstroms). It interacts with deoxygenated hemoglobin beta subunits and decreases the affinity for oxygen and allosterically promotes the release of the remaining oxygen molecules bound to th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adenosine Triphosphate
Adenosine triphosphate (ATP) is an organic compound that provides energy to drive many processes in living cells, such as muscle contraction, nerve impulse propagation, condensate dissolution, and chemical synthesis. Found in all known forms of life, ATP is often referred to as the "molecular unit of currency" of intracellular energy transfer. When consumed in metabolic processes, it converts either to adenosine diphosphate (ADP) or to adenosine monophosphate (AMP). Other processes regenerate ATP. The human body recycles its own body weight equivalent in ATP each day. It is also a precursor to DNA and RNA, and is used as a coenzyme. From the perspective of biochemistry, ATP is classified as a nucleoside triphosphate, which indicates that it consists of three components: a nitrogenous base (adenine), the sugar ribose, and the Polyphosphate, triphosphate. Structure ATP consists of an adenine attached by the 9-nitrogen atom to the 1′ carbon atom of a sugar (ribose), which i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basal Metabolic Rate
Basal metabolic rate (BMR) is the rate of food energy, energy expenditure per unit time by endotherm, endothermic animals at rest. It is reported in energy units per unit time ranging from watt (joule/second) to ml O2/min or joule per hour per kg body mass J/(h·kg). Proper measurement requires a strict set of criteria to be met. These criteria include being in a physically and psychologically undisturbed state and being in a Thermal neutral zone, thermally neutral environment while in the post-absorptive state (i.e., not actively digesting food). In Bradymetabolism, bradymetabolic animals, such as fish and reptiles, the equivalent term standard metabolic rate (SMR) applies. It follows the same criteria as BMR, but requires the documentation of the temperature at which the metabolic rate was measured. This makes BMR a variant of standard metabolic rate measurement that excludes the temperature data, a practice that has led to problems in defining "standard" rates of metabolism for ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blood Sugar
Glycaemia, also known as blood sugar level, blood sugar concentration, or blood glucose level is the measure of glucose concentrated in the blood of humans or other animals. Approximately 4 grams of glucose, a simple sugar, is present in the blood of a 70 kg (154 lb) human at all times. The body tightly regulates blood glucose levels as a part of metabolic homeostasis. Glucose is stored in skeletal muscle and liver cells in the form of glycogen; in fasting individuals, blood glucose is maintained at a constant level at the expense of glycogen stores in the liver and skeletal muscle. In humans, a blood glucose level of 4 grams, or about a teaspoon, is critical for normal function in a number of tissues, and the human brain consumes approximately 60% of blood glucose in fasting, sedentary individuals. A persistent elevation in blood glucose leads to glucose toxicity, which contributes to cell dysfunction and the pathology grouped together as complications of diabetes. Gl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glucagon
Glucagon is a peptide hormone, produced by alpha cells of the pancreas. It raises concentration of glucose and fatty acids in the bloodstream, and is considered to be the main catabolic hormone of the body. It is also used as a Glucagon (medication), medication to treat a number of health conditions. Its effect is opposite to that of insulin, which lowers extracellular glucose. It is produced from proglucagon, encoded by the ''GCG'' gene. The pancreas releases glucagon when the amount of glucose in the bloodstream is too low. Glucagon causes the liver to engage in glycogenolysis: converting stored glycogen into glucose, which is released into the bloodstream. High blood-glucose levels, on the other hand, stimulate the release of insulin. Insulin allows glucose to be taken up and used by insulin-dependent tissues. Thus, glucagon and insulin are part of a feedback system that keeps blood glucose levels stable. Glucagon increases energy expenditure and is elevated under conditions of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Insulin
Insulin (, from Latin ''insula'', 'island') is a peptide hormone produced by beta cells of the pancreatic islets encoded in humans by the ''INS'' gene. It is considered to be the main anabolic hormone of the body. It regulates the metabolism of carbohydrates, fats and protein by promoting the absorption of glucose from the blood into liver, fat and skeletal muscle cells. In these tissues the absorbed glucose is converted into either glycogen via glycogenesis or fats (triglycerides) via lipogenesis, or, in the case of the liver, into both. Glucose production and secretion by the liver is strongly inhibited by high concentrations of insulin in the blood. Circulating insulin also affects the synthesis of proteins in a wide variety of tissues. It is therefore an anabolic hormone, promoting the conversion of small molecules in the blood into large molecules inside the cells. Low insulin levels in the blood have the opposite effect by promoting widespread catabolism, especially o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Red Blood Cell
Red blood cells (RBCs), also referred to as red cells, red blood corpuscles (in humans or other animals not having nucleus in red blood cells), haematids, erythroid cells or erythrocytes (from Greek ''erythros'' for "red" and ''kytos'' for "hollow vessel", with ''-cyte'' translated as "cell" in modern usage), are the most common type of blood cell and the vertebrate's principal means of delivering oxygen (O2) to the body tissues—via blood flow through the circulatory system. RBCs take up oxygen in the lungs, or in fish the gills, and release it into tissues while squeezing through the body's capillaries. The cytoplasm of a red blood cell is rich in hemoglobin, an iron-containing biomolecule that can bind oxygen and is responsible for the red color of the cells and the blood. Each human red blood cell contains approximately 270 million hemoglobin molecules. The cell membrane is composed of proteins and lipids, and this structure provides properties essential for physiolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amino Acids
Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha amino acids appear in the genetic code. Amino acids can be classified according to the locations of the core structural functional groups, as Alpha and beta carbon, alpha- , beta- , gamma- or delta- amino acids; other categories relate to Chemical polarity, polarity, ionization, and side chain group type (aliphatic, Open-chain compound, acyclic, aromatic, containing hydroxyl or sulfur, etc.). In the form of proteins, amino acid '' residues'' form the second-largest component (water being the largest) of human muscles and other tissues. Beyond their role as residues in proteins, amino acids participate in a number of processes such as neurotransmitter transport and biosynthesis. It is thought that they played a key role in enabling lif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fatty Acids
In chemistry, particularly in biochemistry, a fatty acid is a carboxylic acid with an aliphatic chain, which is either saturated or unsaturated. Most naturally occurring fatty acids have an unbranched chain of an even number of carbon atoms, from 4 to 28. Fatty acids are a major component of the lipids (up to 70% by weight) in some species such as microalgae but in some other organisms are not found in their standalone form, but instead exist as three main classes of esters: triglycerides, phospholipids, and cholesteryl esters. In any of these forms, fatty acids are both important dietary sources of fuel for animals and important structural components for cells. History The concept of fatty acid (''acide gras'') was introduced in 1813 by Michel Eugène Chevreul, though he initially used some variant terms: ''graisse acide'' and ''acide huileux'' ("acid fat" and "oily acid"). Types of fatty acids Fatty acids are classified in many ways: by length, by saturation vs unsatura ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fasting
Fasting is the abstention from eating and sometimes drinking. From a purely physiological context, "fasting" may refer to the metabolic status of a person who has not eaten overnight (see " Breakfast"), or to the metabolic state achieved after complete digestion and absorption of a meal. Metabolic changes in the fasting state begin after absorption of a meal (typically 3–5 hours after eating). A diagnostic fast refers to prolonged fasting from 1 to 100 hours (depending on age) conducted under observation to facilitate the investigation of a health complication, usually hypoglycemia. Many people may also fast as part of a medical procedure or a check-up, such as preceding a colonoscopy or surgery, or before certain medical tests. Intermittent fasting is a technique sometimes used for weight loss that incorporates regular fasting into a person's dietary schedule. Fasting may also be part of a religious ritual, often associated with specifically scheduled fast days, as determ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
