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Millepora Tenera
''Millepora tenera'' is a species of fire coral in the family Milleporidae. It is native to the Red Sea and the western Indo-Pacific region and is a zooxanthellate species with a calcareous skeleton. It was first described in 1949 by the Dutch zoologist Hilbrand Boschma. Distribution and habitat ''Millepora tenera'' is native to the western Indo-Pacific. Its range extends from the Red Sea and the eastern coast of Africa to Japan, Australia, American Samoa and the Mariana Islands. It is found at depths down to about , often in turbid locations where it is tolerant of some degree of siltation. Toxicity Like other fire corals, ''Millepora tenera'' can cause painful rashes when touched by bare skin. Extracts of this coral contain neurotoxins, and can cause convulsions, respiratory failure and death in mice. The extract causes hemolysis, contains a dermonecrotic factor and has antigenic properties. Rabbits immunised with the extract developed neutralising antibodies that were protec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hilbrand Boschma
Hilbrand Boschma (22 April 1893 – 22 July 1976) was a Dutch zoologist and director of the Rijksmuseum of Natural History in Leiden. Boschma studied botany and zoology at the University of Amsterdam. He went to the former Dutch East Indies, where he studied embryology, functional morphology in reptiles and amphibians, and stony corals. He joined a Danish expedition to the Kai Islands in 1922 as an associate of the Danish zoologist Dr. Th. Mortensen and sampled and studied corals. He is taxon author of (among other invertebrate organisms) several different species of fire corals. Thereafter Boschma went back to The Netherlands to take up the post of chief assistant at the Zoological Laboratory of the State University at Leiden. In 1925 he started giving lectures in general zoology for medical students, and in 1931 he became professor of general zoology. In 1934 Boschma became director of the Rijksmuseum of Natural History in Leiden. He was the first director who was speciali ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cytotoxic Necrotising Factor Family
In molecular biology, the cytotoxic necrotising factor family of proteins includes bacterial cytotoxic necrotising factor proteins and the related dermonecrotic toxin (DNT) from ''Bordetella'' species. Cytotoxic necrotizing factor 1 (CNF1) is a toxin whose structure from ''Escherichia coli'' revealed a 4-layer alpha/beta/beta/alpha structure containing mixed beta-sheets. CNF1 is expressed in strains of ''E. coli'' causing uropathogenic and neonatal meningitis. CNF1 alters host cell actin cytoskeleton and promotes bacterial invasion of the blood–brain barrier endothelial cells. CNF1 belongs to a unique group of large cytotoxins that cause constitutive activation of Rho guanosine triphosphatases (GTPases), which are key regulators of the actin cytoskeleton . ''Bordetella'' dermonecrotic toxin (DNT) stimulates the assembly of actin stress fibres and focal adhesions by deamidating or polyaminating Gln63 of the small GTPase Rho. DNT is an A-B toxin composed of an N-terminal recepto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Least-concern Species
A least-concern species is a species that has been categorized by the International Union for Conservation of Nature (IUCN) as evaluated as not being a focus of species conservation because the specific species is still plentiful in the wild. They do not qualify as threatened, near threatened, or (before 2001) conservation dependent. Species cannot be assigned the "Least Concern" category unless they have had their population status evaluated. That is, adequate information is needed to make a direct, or indirect, assessment of its risk of extinction based on its distribution or population status. Evaluation Since 2001 the category has had the abbreviation "LC", following the IUCN 2001 Categories & Criteria (version 3.1). Before 2001 "least concern" was a subcategory of the "Lower Risk" category and assigned the code "LR/lc" or lc. Around 20% of least concern taxa (3261 of 15636) in the IUCN database still use the code "LR/lc", which indicates they have not been re-evaluate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Union For Conservation Of Nature
The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natural resources. It is involved in data gathering and analysis, research, field projects, advocacy, and education. IUCN's mission is to "influence, encourage and assist societies throughout the world to conserve nature and to ensure that any use of natural resources is equitable and ecologically sustainable". Over the past decades, IUCN has widened its focus beyond conservation ecology and now incorporates issues related to sustainable development in its projects. IUCN does not itself aim to mobilize the public in support of nature conservation. It tries to influence the actions of governments, business and other stakeholders by providing information and advice and through building partnerships. The organization is best known to the wider pu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coral Bleaching
Coral bleaching is the process when corals become white due to various stressors, such as changes in temperature, light, or nutrients. Bleaching occurs when coral polyps expel the zooxanthellae (dinoflagellates that are commonly referred to as algae) that live inside their tissue, causing the coral to turn white. The zooxanthellae are photosynthetic, and as the water temperature rises, they begin to produce reactive oxygen species. This is toxic to the coral, so the coral expels the zooxanthellae. Since the zooxanthellae produce the majority of coral colouration, the coral tissue becomes transparent, revealing the coral skeleton made of calcium carbonate. Most bleached corals appear bright white, but some are blue, yellow, or pink due to pigment proteins in the coral. The leading cause of coral bleaching is rising ocean temperature due to climate change. A temperature about 1 °C (or 2 °F) above average can cause bleaching. According to the United Nations Environment Pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Millepora Alcicornis
''Millepora alcicornis'', or sea ginger, is a species of colonial fire coral with a calcareous skeleton. It is found on shallow water coral reefs in the tropical west Atlantic Ocean. It shows a variety of different morphologies depending on its location. It feeds on plankton and derives part of its energy requirements from microalgae found within its tissues. It is an important member of the reef building community and subject to the same threats as other corals. It can cause painful stings to unwary divers. Taxonomy ''Millepora alcicornis'' is not a true coral in class Anthozoa but is in class Hydrozoa, and is more closely related to jellyfish than stony corals. Because of the variability in growth habit that this coral exhibits, it has been the subject of much confusion as to its taxonomy, being described under a number of different names from different localities. In 1898, Hickson decided that the variations in morphology were due to environmental factors and that ''Millepora a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antiserum
Antiserum is a blood serum containing monoclonal or polyclonal antibodies that is used to spread passive immunity to many diseases via blood donation (plasmapheresis). For example, convalescent serum, passive antibody transfusion from a previous human survivor, used to be the only known effective treatment for ebola infection with a high success rate of 7 out of 8 patients surviving. Antisera are widely used in diagnostic virology laboratories. The most common use of antiserum in humans is as antitoxin or antivenom to treat envenomation. Serum therapy, also known as serotherapy, describes the treatment of infectious disease using the serum of animals that have been immunized against the specific organisms or their product, to which the disease is supposedly referable. History In 1890, Emil Behring and Kitasato Shibasaburō published their first paper on serum therapy. Behring had pioneered the technique, using guinea pigs to produce serum. Based on his observation that people ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antibody
An antibody (Ab), also known as an immunoglobulin (Ig), is a large, Y-shaped protein used by the immune system to identify and neutralize foreign objects such as pathogenic bacteria and viruses. The antibody recognizes a unique molecule of the pathogen, called an antigen. Each tip of the "Y" of an antibody contains a paratope (analogous to a lock) that is specific for one particular epitope (analogous to a key) on an antigen, allowing these two structures to bind together with precision. Using this binding mechanism, an antibody can ''tag'' a microbe or an infected cell for attack by other parts of the immune system, or can neutralize it directly (for example, by blocking a part of a virus that is essential for its invasion). To allow the immune system to recognize millions of different antigens, the antigen-binding sites at both tips of the antibody come in an equally wide variety. In contrast, the remainder of the antibody is relatively constant. It only occurs in a few varia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antigen
In immunology, an antigen (Ag) is a molecule or molecular structure or any foreign particulate matter or a pollen grain that can bind to a specific antibody or T-cell receptor. The presence of antigens in the body may trigger an immune response. The term ''antigen'' originally referred to a substance that is an antibody generator. Antigens can be proteins, peptides (amino acid chains), polysaccharides (chains of monosaccharides/simple sugars), lipids, or nucleic acids. Antigens are recognized by antigen receptors, including antibodies and T-cell receptors. Diverse antigen receptors are made by cells of the immune system so that each cell has a specificity for a single antigen. Upon exposure to an antigen, only the lymphocytes that recognize that antigen are activated and expanded, a process known as clonal selection. In most cases, an antibody can only react to and bind one specific antigen; in some instances, however, antibodies may cross-react and bind more than one antigen. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
Species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neurotoxin
Neurotoxins are toxins that are destructive to nerve tissue (causing neurotoxicity). Neurotoxins are an extensive class of exogenous chemical neurological insultsSpencer 2000 that can adversely affect function in both developing and mature nervous tissue.Olney 2002 The term can also be used to classify endogenous compounds, which, when abnormally contacted, can prove neurologically toxic. Though neurotoxins are often neurologically destructive, their ability to specifically target neural components is important in the study of nervous systems. Common examples of neurotoxins include lead, ethanol (drinking alcohol), glutamate,Choi 1987 nitric oxide, botulinum toxin (e.g. Botox), tetanus toxin,Simpson 1986 and tetrodotoxin. Some substances such as nitric oxide and glutamate are in fact essential for proper function of the body and only exert neurotoxic effects at excessive concentrations. Neurotoxins inhibit neuron control over ion concentrations across the cell membrane, or com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
