|
Hemoglobinopathy
Hemoglobinopathy is the medical term for a group of inherited blood disorders involving the hemoglobin, the major protein of red blood cells. They are generally single-gene disorders and, in most cases, they are inherited as Autosome, autosomal Recessive disorders, recessive traits. There are two main groups: abnormal structural hemoglobin variants caused by mutations in the hemoglobin genes, and the thalassemias, which are caused by an underproduction of otherwise normal hemoglobin molecules. The main structural hemoglobin variants are HbS, HbE and HbC. The main types of thalassemia are alpha-thalassemia and beta thalassemia. Hemoglobin functions Hemoglobin is a protein containing ferrous, iron that facilitates the transportation of oxygen in Red blood cell, red blood cells. Hemoglobin in the blood carries oxygen from the Lung, lungs to the other tissues of the body, where it releases the oxygen to enable aerobic respiration which powers the metabolism. Normal levels of hemoglob ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blood Disorders
Hematologic diseases are disorders which primarily affect the blood and Blood formation, blood-forming organs. Hematologic diseases include rare genetic disorders, anemia, HIV, sickle cell disease and complications from chemotherapy or transfusions. Myeloid * Hemoglobinopathy, Hemoglobinopathies (congenital abnormality of the hemoglobin molecule or of the rate of hemoglobin synthesis) ** Sickle cell disease ** Thalassemia ** Methemoglobinemia * Anemias (lack of red blood cells or hemoglobin) ** Iron-deficiency anemia ** Megaloblastic anemia *** Vitamin B12, Vitamin B12 deficiency **** Pernicious anemia *** Folate deficiency ** Hemolytic anemias (destruction of red blood cells) *** Genetic disorders of RBC membrane **** Hereditary spherocytosis **** Hereditary elliptocytosis **** Congenital dyserythropoietic anemia *** Genetic disorders of RBC metabolism **** Glucose-6-phosphate dehydrogenase deficiency (G6PD) **** Pyruvate kinase deficiency *** Immune mediated hemolytic anemia (Co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thalassemia
Thalassemias are a group of Genetic disorder, inherited blood disorders that manifest as the production of reduced hemoglobin. Symptoms depend on the type of thalassemia and can vary from none to severe, including death. Often there is mild to severe anemia (low red blood cells or hemoglobin) as thalassemia can affect the production of red blood cells and also affect how long the red blood cells live. Symptoms include fatigue (medical), tiredness, pallor, bone problems, an splenomegaly, enlarged spleen, jaundice, pulmonary hypertension, and dark urine. A child's growth and development may be slower than normal. Thalassemias are genetic disorders. Alpha thalassemia is caused by deficient production of the Hemoglobin subunit alpha, alpha globin component of hemoglobin, while beta thalassemia is a deficiency in the Hemoglobin subunit beta, beta globin component. The severity of alpha and beta thalassemia depends on how many of the four genes for alpha globin or two genes for beta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpha-thalassemia
Alpha-thalassemia (α-thalassemia, α-thalassaemia) is an inherited blood disorder and a form of thalassemia. Thalassemias are a group of inherited blood conditions which result in the impaired production of hemoglobin, the molecule that carries oxygen in the blood. Symptoms depend on the extent to which hemoglobin is deficient, and include anemia, pallor, tiredness, enlargement of the spleen, iron overload, abnormal bone structure, jaundice, and gallstones. In severe cases death ensues, often in infancy, or death of the unborn fetus. The disease is characterised by reduced production of the alpha-globin component of hemoglobin, caused by inherited mutations affecting the genes ''HBA1'' and ''HBA2.'' This causes reduced levels of hemoglobin leading to anemia, while the accumulation of surplus beta-globin, the other structural component of hemoglobin, damages red blood cells and shortens their life. Diagnosis is by checking the medical history of near relatives, microscopi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beta Thalassemia
Beta-thalassemia (β-thalassemia) is an genetic disorder, inherited hemoglobinopathy, blood disorder, a form of thalassemia resulting in variable outcomes ranging from clinically asymptomatic to severe anemia individuals. It is caused by reduced or absent synthesis of the HBB, beta chains of hemoglobin, the molecule that carries oxygen in the blood. Symptoms depend on the extent to which hemoglobin is deficient, and include anemia, pallor, Fatigue, tiredness, Splenomegaly, enlargement of the spleen, jaundice, and Gallstone, gallstones. In severe cases death ensues. Beta thalassemia occurs due to a mutation of the HBB gene leading to deficient production of the hemoglobin subunit Hemoglobin subunit beta, beta-globin; the severity of the disease depends on the nature of the mutation, and whether or not the mutation is Zygosity, homozygous. The body's inability to construct beta-globin leads to reduced or zero production of Hemoglobin A, adult hemoglobin thus causing anemia. The ot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemoglobin
Hemoglobin (haemoglobin, Hb or Hgb) is a protein containing iron that facilitates the transportation of oxygen in red blood cells. Almost all vertebrates contain hemoglobin, with the sole exception of the fish family Channichthyidae. Hemoglobin in the blood carries oxygen from the respiratory organs (lungs or gills) to the other tissues of the body, where it releases the oxygen to enable aerobic respiration which powers an animal's metabolism. A healthy human has 12to 20grams of hemoglobin in every 100mL of blood. Hemoglobin is a metalloprotein, a chromoprotein, and a globulin. In mammals, hemoglobin makes up about 96% of a red blood cell's dry matter, dry weight (excluding water), and around 35% of the total weight (including water). Hemoglobin has an oxygen-binding capacity of 1.34mL of O2 per gram, which increases the total blood oxygen capacity seventy-fold compared to dissolved oxygen in blood plasma alone. The mammalian hemoglobin molecule can bind and transport up to four ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adult Hemoglobin
Hemoglobin A (HbA), also known as adult hemoglobin, hemoglobin A1 or α2β2, is the most common human hemoglobin tetramer, accounting for over 97% of the total red blood cell hemoglobin. Hemoglobin is an oxygen-binding protein, found in erythrocytes, which transports oxygen from the lungs to the tissues. Hemoglobin A is the most common adult form of hemoglobin and exists as a tetramer containing two alpha subunits and two beta subunits (α2β2). Hemoglobin A2 (HbA2) is a less common adult form of hemoglobin and is composed of two alpha and two delta-globin subunits. This hemoglobin makes up 1-3% of hemoglobin in adults. Structure and function Hemoglobin A (HbA) is the most common adult form of hemoglobin and exists as a tetramer containing two alpha subunits and two beta subunits (α2β2). Each subunit contains a heme group that diatomic oxygen (O2) molecules can bind to. In addition to oxygen, subunit assembly and quaternary structure are known to play important roles in Hb a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fetal Hemoglobin
Fetal hemoglobin, or foetal haemoglobin (also hemoglobin F, HbF, or α2γ2) is the main oxygen carrier protein in the human fetus. HemoglobinF is found in fetal red blood cells, and is involved in transporting oxygen from the mother's bloodstream to organs and tissues in the fetus. It is produced at around 6weeks of pregnancy and the levels remain high after birth until the baby is roughly 2–4months old. HemoglobinF has a different composition than adult forms of hemoglobin, allowing it to bind (or attach to) oxygen more strongly; this in turn enables the developing fetus to retrieve oxygen from the mother's bloodstream, which occurs through the placenta found in the mother's uterus. In the newborn, levels of hemoglobin F gradually decrease and reach adult levels (less than 1% of total hemoglobin) usually within the first year, as adult forms of hemoglobin begin to be produced. Diseases such as beta thalassemias, which affect components of the adult hemoglobin, can delay this ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Embryogenesis
An embryo ( ) is the initial stage of development for a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male sperm cell. The resulting fusion of these two cells produces a single-celled zygote that undergoes many cell divisions that produce cells known as blastomeres. The blastomeres (4-cell stage) are arranged as a solid ball that when reaching a certain size, called a morula, (16-cell stage) takes in fluid to create a cavity called a blastocoel. The structure is then termed a blastula, or a blastocyst in mammals. The mammalian blastocyst hatches before implantating into the endometrial lining of the womb. Once implanted the embryo will continue its development through the next stages of gastrulation, neurulation, and organogenesis. Gastrulation is the formation of the three germ layers that will form all of the different parts o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hb A2
Hemoglobin A2 (HbA2) is a normal variant of hemoglobin A that consists of two alpha and two delta chains (α2δ2) and is found at low levels in normal human blood. Hemoglobin A2 may be increased in beta thalassemia or in people who are heterozygous for the beta thalassemia gene. HbA2 exists in small amounts in all adult humans (1.5–3.1% of all hemoglobin molecules) and is approximately normal in people with sickle-cell disease Sickle cell disease (SCD), also simply called sickle cell, is a group of inherited haemoglobin-related blood disorders. The most common type is known as sickle cell anemia. Sickle cell anemia results in an abnormality in the oxygen-carrying .... Its biological importance is not yet known. HbA2 may seem physiologically minor, but it plays a very crucial role in identifying the beta-thalassemia traits, also known as BTT, and identifying other hemoglobin disorders. Human hemoglobin is made up of two different chains, this includes alpha-globin and b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heme Protein
A hemeprotein (or haemprotein; also hemoprotein or haemoprotein), or heme protein, is a protein that contains a heme prosthetic group. They are a very large class of metalloproteins. The heme group confers functionality, which can include oxygen carrying, oxygen reduction, electron transfer, and other processes. Heme is bound to the protein either covalently or noncovalently or both. The heme consists of iron cation bound at the center of the conjugate base of the porphyrin, as well as other ligands attached to the "axial sites" of the iron. The porphyrin ring is a planar dianionic, tetradentate ligand. The iron is typically Fe2+ or Fe3+. One or two ligands are attached at the axial sites. The porphyrin ring has four nitrogen atoms that bind to the iron, leaving two other coordination positions of the iron available for bonding to the histidine of the protein and a divalent atom. Hemeproteins probably evolved to incorporate the iron atom contained within the protoporphyri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Embryonic Hemoglobin
The human embryonic haemoglobins were discovered in 1961. These include Hb-Gower 1, consisting of 2 zeta chains and 2 epsilon chains, and Hb-Gower 2, which consists of 2 αlpha-chains and 2 epsilon-chains, the zeta and epsilon chains being the embryonic haemoglobin chains. Embryonic hemoglobin is a tetramer produced in the blood islands in the embryonic yolk sac during the mesoblastic stage (from 3rd week of pregnancy until 3 months). The protein is commonly referred to as hemoglobin ε. Chromosomal abnormalities can lead to a delay in switching from embryonic hemoglobin. Hemoglobin Gower 1 Hemoglobin Gower 1 (also referred to as ζ2ε2 or Hb Gower-1) is a form of hemoglobin existing only during embryonic life, and is the primary embryonic hemoglobin. It is composed of two zeta chains and two epsilon chains, and is relatively unstable, breaking down easily. Hemoglobin Gower 2 Hemoglobin Gower 2 (also referred to as α2ε2 or Hb Gower-2) is a form of hemoglobin existing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moiety (chemistry)
In organic chemistry, a moiety ( ) is a part of a molecule that is given a name because it is identified as a part of other molecules as well. Typically, the term is used to describe the larger and characteristic parts of organic molecules, and it should not be used to describe or name smaller functional groups of atoms that chemically react in similar ways in most molecules that contain them. Occasionally, a moiety may contain smaller moieties and functional groups. A moiety that acts as a branch extending from the backbone of a hydrocarbon molecule is called a substituent or side chain, which typically can be removed from the molecule and substituted with others. The term is also used in pharmacology, where an active moiety is the part of a molecule responsible for the physiological or pharmacological action of a drug. Active moiety In pharmacology, an active moiety is the part of a molecule or ion—excluding appended inactive portions—that is responsible for the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
