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Hemolysis
Hemolysis or haemolysis (), also known by several other names, is the rupturing (lysis) of red blood cells (erythrocytes) and the release of their contents (cytoplasm) into surrounding fluid (e.g. blood plasma). Hemolysis may occur in vivo or in vitro. One cause of hemolysis is the action of hemolysins, toxins that are produced by certain pathogenic bacteria or fungi. Another cause is intense physical exercise. Hemolysins damage the red blood cell's cytoplasmic membrane, causing lysis and eventually cell death. Etymology From hemo- + -lysis, from , "blood") + , "loosening"). Inside the body Hemolysis inside the body can be caused by a large number of medical conditions, including some parasites (''e.g.'', ''Plasmodium''), some autoimmune disorders (''e.g.'', autoimmune haemolytic anaemia, drug-induced hemolytic anemia, atypical hemolytic uremic syndrome (aHUS)), some genetic disorders (''e.g.'', Sickle-cell disease or G6PD deficiency), or blood with too low a solute conc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemolytic Anemia
Hemolytic anemia or haemolytic anaemia is a form of anemia due to hemolysis, the abnormal breakdown of red blood cells (RBCs), either in the blood vessels (intravascular hemolysis) or elsewhere in the human body (extravascular). This most commonly occurs within the spleen, but also can occur in the reticuloendothelial system or mechanically (prosthetic valve damage). Hemolytic anemia accounts for 5% of all existing anemias. It has numerous possible consequences, ranging from general symptoms to life-threatening systemic effects. The general classification of hemolytic anemia is either intrinsic or extrinsic. Treatment depends on the type and cause of the hemolytic anemia. Symptoms of hemolytic anemia are similar to other forms of anemia ( fatigue and shortness of breath), but in addition, the breakdown of red cells leads to jaundice and increases the risk of particular long-term complications, such as gallstones and pulmonary hypertension. Signs and symptoms Symptoms of hemolytic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HELLP Syndrome
HELLP syndrome is a complication of pregnancy; the acronym stands for hemolysis, elevated liver enzymes, and low platelet count. It usually begins during the last three months of pregnancy or shortly after childbirth. Symptoms may include feeling tired, retaining fluid, headache, nausea, upper right abdominal pain, blurry vision, nosebleeds, and seizures. Complications may include disseminated intravascular coagulation, placental abruption, and kidney failure. The cause is unknown. The condition occurs in association with pre-eclampsia or eclampsia. Other risk factors include previously having the syndrome and a mother older than 25 years. The underlying mechanism may involve abnormal placental development. Diagnosis is generally based on blood tests finding signs of red blood cell breakdown (lactate dehydrogenase greater than 600 U/L), an aspartate transaminase greater than 70 U/L, and platelets less than 100×109/l. If not all the criteria are present, the condition is incompl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
G6PD Deficiency
Glucose-6-phosphate dehydrogenase deficiency (G6PDD), which is the most common enzyme deficiency worldwide, is an inborn error of metabolism that predisposes to red blood cell breakdown. Most of the time, those who are affected have no symptoms. Following a specific trigger, symptoms such as yellowish skin, dark urine, shortness of breath, and feeling tired may develop. Complications can include anemia and newborn jaundice. Some people never have symptoms. It is an X-linked recessive disorder that results in defective glucose-6-phosphate dehydrogenase enzyme. Glucose-6-phosphate dehydrogenase is an enzyme which protects red blood cells, which carry oxygen from the lungs to tissues throughout the body. A defect of the enzyme results in the premature breakdown of red blood cells. This destruction of red blood cells is called hemolysis. Red blood cell breakdown may be triggered by infections, certain medication, stress, or foods such as fava beans. Depending on the specific mutatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemolysin
Hemolysins or haemolysins are lipids and proteins that cause lysis of red blood cells by disrupting the cell membrane. Although the lytic activity of some microbe-derived hemolysins on red blood cells may be of great importance for nutrient acquisition, many hemolysins produced by pathogens do not cause significant destruction of red blood cells during infection. However, hemolysins are often capable of lysing red blood cells ''in vitro''. While most hemolysins are protein compounds, some are lipid biosurfactants. Properties Many bacteria produce hemolysins that can be detected in the laboratory. It is now believed that many clinically relevant fungi also produce hemolysins. Hemolysins can be identified by their ability to lyse red blood cells ''in vitro''. Not only are the erythrocytes affected by hemolysins, but there are also some effects among other blood cells, such as leucocytes (white blood cells). ''Escherichia coli'' hemolysin is potentially cytotoxic to monocytes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemolysin
Hemolysins or haemolysins are lipids and proteins that cause lysis of red blood cells by disrupting the cell membrane. Although the lytic activity of some microbe-derived hemolysins on red blood cells may be of great importance for nutrient acquisition, many hemolysins produced by pathogens do not cause significant destruction of red blood cells during infection. However, hemolysins are often capable of lysing red blood cells ''in vitro''. While most hemolysins are protein compounds, some are lipid biosurfactants. Properties Many bacteria produce hemolysins that can be detected in the laboratory. It is now believed that many clinically relevant fungi also produce hemolysins. Hemolysins can be identified by their ability to lyse red blood cells ''in vitro''. Not only are the erythrocytes affected by hemolysins, but there are also some effects among other blood cells, such as leucocytes (white blood cells). ''Escherichia coli'' hemolysin is potentially cytotoxic to monocytes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemoglobinemia
Hemoglobinemia (or haemoglobinaemia) is a medical condition in which there is an excess of hemoglobin in the blood plasma. This is an effect of intravascular hemolysis, in which hemoglobin separates from red blood cells, a form of anemia. Hemoglobinemia can be caused by intrinsic or extrinsic factors. When hemoglobinemia is internally caused, it is a result of recessive genetic defects that cause the red blood cells to lyse, letting the hemoglobin spill out of the cell into the blood plasma. In intravascular hemolysis, hemoglobin is released and binds with haptoglobin. This causes haptoglobin levels to decrease. Once haptoglobin is saturated, free hemoglobin readily distributes to tissues where it might be exposed to oxidative conditions. In such conditions, heme can be released from ferric hemoglobin. The free heme can then accelerate tissue damage by promoting peroxidative reactions and activation of inflammatory cascades. Hemopexin (Hx) is another plasma glycoprotein able to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pre-eclampsia
Pre-eclampsia is a disorder of pregnancy characterized by the onset of high blood pressure and often a significant amount of protein in the urine. When it arises, the condition begins after 20 weeks of pregnancy. In severe cases of the disease there may be red blood cell breakdown, a low blood platelet count, impaired liver function, kidney dysfunction, swelling, shortness of breath due to fluid in the lungs, or visual disturbances. Pre-eclampsia increases the risk of undesirable outcomes for both the mother and the fetus. If left untreated, it may result in seizures at which point it is known as eclampsia. Risk factors for pre-eclampsia include obesity, prior hypertension, older age, and diabetes mellitus. It is also more frequent in a woman's first pregnancy and if she is carrying twins. The underlying mechanism involves abnormal formation of blood vessels in the placenta amongst other factors. Most cases are diagnosed before delivery. Commonly, pre-eclampsia continues i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemoglobin
Hemoglobin (haemoglobin BrE) (from the Greek word αἷμα, ''haîma'' 'blood' + Latin ''globus'' 'ball, sphere' + ''-in'') (), abbreviated Hb or Hgb, is the iron-containing oxygen-transport metalloprotein present in red blood cells (erythrocytes) of almost all vertebrates (the exception being the fish family Channichthyidae) as well as the tissues of some invertebrates. Hemoglobin in blood carries oxygen from the respiratory organs (''e.g.'' lungs or gills) to the rest of the body (''i.e.'' tissues). There it releases the oxygen to permit aerobic respiration to provide energy to power functions of an organism in the process called metabolism. A healthy individual human has 12to 20grams of hemoglobin in every 100mL of blood. In mammals, the chromoprotein makes up about 96% of the red blood cells' dry content (by weight), and around 35% of the total content (including water). Hemoglobin has an oxygen-binding capacity of 1.34mL O2 per gram, which increases the total blood oxygen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atypical Hemolytic Uremic Syndrome
Atypical hemolytic uremic syndrome (aHUS) is an extremely rare, life-threatening, progressive disease that frequently has a genetic component. In most cases it can be effectively controlled by interruption of the complement cascade. Particular monoclonal antibodies, discussed later in the article, have proven efficacy in many cases. AHUS is usually caused by chronic, uncontrolled activation of the complement system, a branch of the body's immune system that destroys and removes foreign particles. The disease affects both children and adults and is characterized by systemic thrombotic microangiopathy (TMA), the formation of blood clots in small blood vessels throughout the body, which can lead to stroke, heart attack, kidney failure, and death. The complement system activation may be due to mutations in the complement regulatory proteins (factor H, factor I, or membrane cofactor protein), or is occasionally due to acquired neutralizing autoantibody inhibitors of these complement ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blood Plasma
Blood plasma is a light amber-colored liquid component of blood in which blood cells are absent, but contains proteins and other constituents of whole blood in suspension. It makes up about 55% of the body's total blood volume. It is the intravascular part of extracellular fluid (all body fluid outside cells). It is mostly water (up to 95% by volume), and contains important dissolved proteins (6–8%; e.g., serum albumins, globulins, and fibrinogen), glucose, clotting factors, electrolytes (, , , , , etc.), hormones, carbon dioxide (plasma being the main medium for excretory product transportation), and oxygen. It plays a vital role in an intravascular osmotic effect that keeps electrolyte concentration balanced and protects the body from infection and other blood-related disorders. Blood plasma is separated from the blood by spinning a vessel of fresh blood containing an anticoagulant in a centrifuge until the blood cells fall to the bottom of the tube. The blood plasma is t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sickle-cell Disease
Sickle cell disease (SCD) is a group of blood disorders typically inherited from a person's parents. The most common type is known as sickle cell anaemia. It results in an abnormality in the oxygen-carrying protein haemoglobin found in red blood cells. This leads to a rigid, sickle-like shape under certain circumstances. Problems in sickle cell disease typically begin around 5 to 6 months of age. A number of health problems may develop, such as attacks of pain (known as a sickle cell crisis), anemia, swelling in the hands and feet, bacterial infections and stroke. Long-term pain may develop as people get older. The average life expectancy in the developed world is 40 to 60 years. Sickle cell disease occurs when a person inherits two abnormal copies of the β-globin gene (''HBB'') that makes haemoglobin, one from each parent. This gene occurs in chromosome 11. Several subtypes exist, depending on the exact mutation in each haemoglobin gene. An attack can be set off by temper ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lysis
Lysis ( ) is the breaking down of the membrane of a cell, often by viral, enzymic, or osmotic (that is, "lytic" ) mechanisms that compromise its integrity. A fluid containing the contents of lysed cells is called a ''lysate''. In molecular biology, biochemistry, and cell biology laboratories, cell cultures may be subjected to lysis in the process of purifying their components, as in protein purification, DNA extraction, RNA extraction, or in purifying organelles. Many species of bacteria are subject to lysis by the enzyme lysozyme, found in animal saliva, egg white, and other secretions. Phage lytic enzymes (lysins) produced during bacteriophage infection are responsible for the ability of these viruses to lyse bacterial cells. Penicillin and related β-lactam antibiotics cause the death of bacteria through enzyme-mediated lysis that occurs after the drug causes the bacterium to form a defective cell wall. If the cell wall is completely lost and the penicillin was used ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
