Conformational changes in the A3 domain of von Willebrand factor modulate the interaction of the A1 domain with platelet glycoprotein Ib. (1/687)Bitiscetin has recently been shown to induce von Willebrand factor (vWF)-dependent aggregation of fixed platelets (Hamako J, et al, Biochem Biophys Res Commun 226:273, 1996). We have purified bitiscetin from Bitis arietans venom and investigated the mechanism whereby it promotes a form of vWF that is reactive with platelets. In the presence of bitiscetin, vWF binds to platelets in a dose-dependent and saturable manner. The binding of vWF to platelets involves glycoprotein (GP) Ib because it was totally blocked by monoclonal antibody (MoAb) 6D1 directed towards the vWF-binding site of GPIb. The binding also involves the GPIb-binding site of vWF located on the A1 domain because it was inhibited by MoAb to vWF whose epitopes are within this domain and that block binding of vWF to platelets induced by ristocetin or botrocetin. However, in contrast to ristocetin or botrocetin, the binding site of bitiscetin does not reside within the A1 domain but within the A3 domain of vWF. Thus, among a series of vWF fragments, 125I-bitiscetin only binds to those that overlap the A3 domain, ie, SpIII (amino acid [aa] 1-1365), SpI (aa 911-1365), and rvWF-A3 domain (aa 920-1111). It does not bind to SpII corresponding to the C-terminal part of vWF subunit (aa 1366-2050) nor to the 39/34/kD dispase species (aa 480-718) or T116 (aa 449-728) overlapping the A1 domain. In addition, bitiscetin that does not bind to DeltaA3-rvWF (deleted between aa 910-1113) has no binding site ouside the A3 domain. The localization of the binding site of bitiscetin within the A3 domain was further supported by showing that MoAb to vWF, which are specific for this domain and block the interaction between vWF and collagen, are potent inhibitors of the binding of bitiscetin to vWF and consequently of the bitiscetin-induced binding of vWF to platelets. Thus, our data support the hypothesis that an interaction between the A1 and A3 domains exists that may play a role in the function of vWF by regulating the ability of the A1 domain to bind to platelet GPIb. (+info)
Waglerin-1 selectively blocks the epsilon form of the muscle nicotinic acetylcholine receptor. (2/687)Neonatal mice resist the lethal effect of Waglerin-1. Because Waglerin-1 blocks the nicotinic acetylcholine receptor of mature end-plates, the appearance of lethality may result from the epsilon- for gamma-subunit substitution. In support of this hypothesis, adult knockout (KO) mice lacking the gene coding for the epsilon-subunit resist the lethal effect of Waglerin-1. In contrast, heterozygous litter mates respond to Waglerin-1 like adult wild-type mice. In vitro application of 1 microM Waglerin-1 inhibited spontaneous miniature end-plate potentials and evoked end-plate potentials of adult wild-type and heterozygous KO mice. Both miniature end-plate potentials and end-plate potentials of neonatal wild-type and adult homozygous KO mice resisted Waglerin-1. Waglerin-1 decreased the end-plate response of adult wild-type mice to iontophoretically applied acetylcholine (ACh) with an IC50 value of 50 nM; 1 microM Waglerin-1 decreased the ACh response to 4 +/- 1% of control for adult heterozygous KO mice. In contrast, 1 microM Waglerin-1 decreased the ACh response to 73 +/- 2% of control for wild-type mice less than 11 days old and had no effect on the ACh response of adult homozygous KO mice. Between 11 and 12 days after birth, the suppressant effect of Waglerin-1 on wild-type end-plate responses to ACh dramatically increased. Waglerin-1 reduced binding of alpha-bungarotoxin to end-plates of adult but not neonatal wild-type mice. These data demonstrate that Waglerin-1 selectively blocks the mouse muscle nicotinic acetylcholine receptor containing the epsilon-subunit. (+info)
Identification and characterization of endothelial glycoprotein Ib using viper venom proteins modulating cell adhesion. (3/687)The expression and function of a glycoprotein Ib (GPIb) complex on human umbilical vein endothelial cells (HUVECs) is still a matter of controversy. We characterized HUVEC GPIb using viper venom proteins: alboaggregins A and B, echicetin, botrocetin, and echistatin. Echicetin is an antagonist, and alboaggregins act as agonists of the platelet GPIb complex. Botrocetin is a venom protein that alters von Willebrand factor (vWF) conformation and increases its binding affinity for the GPIb complex. Echistatin is a disintegrin that blocks alphavbeta3. Echistatin, but not echicetin, inhibited the adhesion to vWF of Chinese hamster ovary (CHO) cells transfected with alphavbeta3. We found the following: (1) Binding of monoclonal antibodies against GPIbalpha to HUVECs was moderately increased after stimulation with cytokines and phorbol ester. Echicetin demonstrated an inhibitory effect. (2) Both echicetin and echistatin, an alphavbeta3 antagonist, inhibited the adhesion of HUVECs to immobilized vWF in a dose-dependent manner. The inhibitory effect was additive when both proteins were used together. (3) Botrocetin potentiated the adhesion of HUVECs to vWF, and this effect was completely abolished by echicetin, but not by echistatin. (4) CHO cells expressing GPIbalphabeta/IX adhered to vWF (in the presence of botrocetin) and to alboaggregins; GPIbalpha was required for this reaction. Echicetin, but not echistatin, inhibited the adhesion of cells transfected with GPIbalphabeta/IX to immobilized vWF. (5) HUVECs adhered strongly to immobilized vWF and alboaggregins with extensive spreading, which was inhibited by LJ1b1, a monoclonal antibody against GPIb. The purified alphavbeta3 receptor did not interact with the alboaggregins, thereby excluding the contribution of alphavbeta3 in inducing HUVEC spreading on alboaggregins. In conclusion, our data confirm the presence of a functional GPIb complex expressed on HUVECs in low density. This complex may mediate HUVEC adhesion and spreading on immobilized vWF and alboaggregins. (+info)
Cloning, expression and biochemical characterization of a basic-acidic hybrid phospholipase A2-II from Agkistrodon halys pallas. (4/687)A cDNA encoding a basic-acidic hybrid phospholipase A2-II from Agkistrodon halys Pallas with an N-terminus highly homologous to that of BPLA2 and a C-terminus sequence almost the same as that of APLA2 was inserted into a bacterial expression vector and effectively expressed in Escherichia coli RR1. The protein was produced as insoluble inclusion bodies. After partial purification by washing, the inclusion bodies with Triton X-100, denaturing and refolding, the renatured recombinant protein was purified by FPLC column superose 12. The purified recombinant enzyme with an isoelectric point of pH 6.8 could cross-react with antiserum prepared against acidic phospholipase A2. The enzymatic activity of the expressed basic-acidic hybrid phospholipase A2-II is close to that of denatured-refolded native basic phospholipase A2, and has the same inhibiting effect on platelet aggregation as denatured-refolded acidic phospholipase A2, but lacks the hemolytic activity of denatured-refolded basic phospholipase A2. To study the structural relationships among basic phospholipase A2, acidic phospholipase A2 and basic-acidic hybrid phospholipase A2-II, molecular modeling of basic-acidic hybrid phospholipase A2-II was done. The roles of various amino acid residues in the enzymatic activity and pharmacological activities of phospholipase A2 are discussed. (+info)
Phosphatidylinositol 3'-kinase and tyrosine-phosphatase activation positively modulate Convulxin-induced platelet activation. Comparison with collagen. (5/687)In this report we have studied the role of phosphatidylinositol 3'-kinase (PI3-K) and tyrosine phosphatase activation on platelet activation by Convulxin (Cvx). Wortmannin, a specific PI3-K inhibitor, and phenylarsine oxide (PAO), a sulfhydryl reagent that inhibits tyrosine phosphatase (PTPase), block Cvx-induced platelet aggregation, granule secretion, inositol phosphate production, and increase in [Ca2+]i. However, PAO does not inhibit Cvx-induced tyrosine phosphorylation of platelet proteins, including Syk and PLCgamma2, but blocked collagen-induced platelet aggregation as well as tyrosine phosphorylation of PLCgamma2. In contrast, Cvx-induced PLCgamma2 tyrosyl phosphorylation was partially inhibited by wortmannin. We conclude that (i) although Cvx and collagen activate platelets by a similar mechanism, different regulatory processes are specific to each agonist; (ii) mechanisms other than tyrosine phosphorylation regulate PLCgamma2 activity; and (iii) besides protein tyrosine kinases, PI3-K (and PTPase) positively modulate platelet activation by both Cvx and collagen, and this enzyme is required for effective transmission of GPVI-Fc receptor gamma chain signal to result in full activation and tyrosine phosphorylation of PLCgamma2 in Cvx-stimulated platelets. (+info)
Reduction in lipopolysaccharide-induced thrombocytopenia by triflavin in a rat model of septicemia. (6/687)BACKGROUND: Thrombocytopenia frequently occurs early in the course of Gram-negative bacterial infections. Triflavin, an Arg-Gly-Asp-containing disintegrin, has been suggested to interfere with the interaction of fibrinogen with the glycoprotein IIb/IIIa complex. The present study was undertaken to determine whether triflavin could prevent thrombocytopenia in lipopolysaccharide (LPS)-treated rats. METHODS AND RESULTS: In this study, 51Cr-labeled platelets were used to assess blood and tissue platelet accumulation after LPS challenge. The administration of LPS (4 mg/kg IV bolus) for 4 hours induced a reduction in radiolabeled platelets in blood and an obvious accumulation of platelets in liver. Triflavin (500 microg/kg) but not GRGDS (20 mg/kg) significantly prevented the alteration of radiolabeled platelet distribution in blood and liver when induced by LPS. Furthermore, triflavin but not GRGDS markedly suppressed the elevation in plasma thromboxane B2 concentration within the 4-hour period of LPS administration. In LPS-treated rats, the 5-hydroxytryptamine level was lower in the blood and higher in the liver compared with levels in normal saline-treated rats. Pretreatment with triflavin (500 microg/kg) significantly reversed the 5-hydroxytryptamine concentration in blood and liver of LPS-treated rats. In histological examinations and platelet adhesion assay, triflavin markedly inhibited the adhesion of platelets to subendothelial matrixes in vivo and in vitro. CONCLUSIONS: The results indicate that triflavin effectively prevents thrombocytopenia, possibly through the following 2 mechanisms: (1) Triflavin markedly inhibits platelet aggregation, resulting in decreased thromboxane A2 formation. (2) It inhibits the adhesion of platelets to subendothelial matrixes, thereby leading to a reversal in the distribution of platelets in blood and liver in LPS-treated rats. (+info)
Nucleotide sequence of a cDNA encoding a common precursor of disintegrin flavostatin and hemorrhagic factor HR2a from the venom of Trimeresurus flavoviridis. (7/687)The venom of Trimeresurus flavoviridis has three disintegrins that act as platelet aggregation inhibitors by binding to integrin alphaIIb beta3 on platelets through its Arg-Gly-Asp sequence. We isolated the cDNA encoding the flavostatin precursor that is one of the disintegrins in T. flavoviridis venom. The open reading frame consisted of four regions, a pre-peptide region, a metalloprotease region, a spacer region and a disintegrin region, indicating that the flavostatin precursor belongs to the metalloprotease/disintegrin family. Surprisingly, the deduced amino acid sequence of the metalloprotease region was completely consistent with that of hemorrhagic metalloprotease HR2a, which indicated that this metalloprotease released from the flavostatin precursor functions as a hemorrhagic factor. These observations indicated that a disintegrin and a hemorrhagic metalloprotease were synthesized as a common precursor. Thus, our results support the hypothesis that a disintegrin is synthesized as a metalloprotease/disintegrin precursor and matures by cleavage from the precursor molecule. (+info)
Crystallization and preliminary X-ray diffraction analysis of a myotoxic phospholipase A(2) homologue from Bothrops neuwiedi pauloensis venom. (8/687)Crystals of a myotoxic phospholipase A(2) from Bothrops neuwiedi pauloensis have been obtained. They diffracted at 2.5 A resolution using a synchrotron radiation source and belong to space group P3(1)21. Preliminary analysis shows that there are two molecules in the asymmetric unit. (+info)
Crotalid venoms are the toxic secretions produced by snakes of the family Viperidae, particularly those in the subfamily Crotalinae, which includes rattlesnakes, copperheads, and cottonmouths. These venoms are composed of a complex mixture of proteins, enzymes, and other molecules that can cause a range of physiological effects in humans and other animals. The effects of crotalid venom can vary depending on the species of snake, the size of the snake, and the amount of venom injected. Common symptoms of crotalid envenomation include pain, swelling, redness, and necrosis (tissue death) at the site of the bite. In severe cases, crotalid venom can cause systemic effects such as coagulopathy (disruption of the blood clotting process), cardiovascular collapse, and respiratory failure. Treatment for crotalid envenomation typically involves the administration of antivenom, which is a serum containing antibodies that neutralize the venom's toxic effects. In some cases, supportive care such as pain management, fluid replacement, and wound care may also be necessary. It is important to seek medical attention immediately if you suspect that you or someone else has been bitten by a venomous snake.
Antivenins are a type of medication used to treat venomous bites or stings from animals such as snakes, spiders, scorpions, and others. These medications are made from the venom of the same or similar animals that caused the bite or sting, but they have been purified and weakened so that they are no longer harmful to humans. Antivenins work by neutralizing the toxins in the venom, which can help to prevent or reduce the severity of symptoms such as pain, swelling, nausea, vomiting, and in severe cases, respiratory failure or cardiac arrest. They are typically administered through injection and may be given in a single dose or in a series of doses over several days, depending on the severity of the venomous bite or sting and the individual's response to treatment. It is important to note that antivenins are not effective against all venomous animals and that the specific type of antivenin needed will depend on the type of animal that caused the bite or sting. In some cases, other treatments such as supportive care, pain management, and wound care may also be necessary.
In the medical field, "Crotalus" refers to a genus of venomous snakes that are commonly known as rattlesnakes. There are several species of rattlesnakes, including the eastern diamondback rattlesnake, the western diamondback rattlesnake, and the Mojave rattlesnake, among others. These snakes are found in various parts of the world, including North and South America, and are known for their distinctive rattle at the end of their tails. Rattlesnakes are venomous and can cause serious harm or death if their venom is injected into a person or animal. Treatment for rattlesnake bites typically involves antivenom, which is designed to neutralize the venom and prevent its harmful effects.
Bee venoms are the toxic secretions produced by honeybees, bumblebees, and other types of bees. These venoms contain a complex mixture of proteins, enzymes, and other substances that can cause a range of physiological effects in humans and other animals. In the medical field, bee venom therapy (BVT) is a form of alternative medicine that involves the use of bee venom to treat various conditions. BVT is believed to work by stimulating the body's immune system and promoting the production of natural painkillers called endorphins. BVT has been used to treat a variety of conditions, including arthritis, multiple sclerosis, chronic pain, and allergies. However, the effectiveness of BVT is not well-established, and it can cause serious side effects, including allergic reactions, skin irritation, and even anaphylaxis in some cases. Therefore, the use of bee venom therapy should only be considered under the guidance of a qualified healthcare professional, and patients should be carefully monitored for any adverse reactions.
In the medical field, venoms are toxic substances produced by certain animals, such as snakes, spiders, scorpions, and some fish, that are injected into their prey or predators through specialized structures called venom glands. These venoms contain a complex mixture of proteins, enzymes, and other molecules that can cause a range of physiological effects in the victim, including pain, swelling, paralysis, and even death. Venoms are often used as a defense mechanism by animals to protect themselves from predators or to subdue their prey. In some cases, venoms are also used for hunting or as a means of communication between animals. In medicine, venoms are studied for their potential therapeutic uses, such as in the development of new drugs for pain relief, anti-inflammatory, and anti-cancer treatments. However, venoms can also be dangerous and can cause serious harm or death if not treated properly. Therefore, medical professionals must be trained in the proper handling and treatment of venomous animals and their bites or stings.
Cobra venoms are toxic substances produced by cobras, a group of venomous snakes found in various parts of the world. These venoms contain a complex mixture of proteins, enzymes, and other molecules that can cause a range of physiological effects in humans and other animals. The effects of cobra venom can vary depending on the species of cobra, the dose of venom injected, and the individual's health status. Some common effects of cobra venom include pain, swelling, and muscle spasms at the site of the bite, as well as more systemic effects such as nausea, vomiting, dizziness, and difficulty breathing. In the medical field, cobra venom is studied for its potential therapeutic uses, such as in the development of new drugs for pain management, anti-inflammatory treatments, and cancer therapies. However, cobra venom is also a significant health hazard, and bites from venomous cobras can be life-threatening if not treated promptly and appropriately. Treatment typically involves antivenom therapy, which is designed to neutralize the venom and prevent its harmful effects on the body.
Viper venoms are the toxic secretions produced by venomous snakes of the Viperidae family, including rattlesnakes, copperheads, mambas, and cobras. These venoms contain a complex mixture of proteins, enzymes, and other molecules that can cause a range of physiological effects in humans and other animals. The effects of viper venom can vary depending on the species of snake, the amount of venom injected, and the location of the bite. Some common symptoms of viper venom poisoning include pain, swelling, redness, and blistering at the site of the bite, as well as nausea, vomiting, dizziness, weakness, and difficulty breathing. In severe cases, viper venom can cause systemic effects such as kidney failure, respiratory failure, and even death. Treatment for viper venom poisoning typically involves antivenom, which is a serum containing antibodies that can neutralize the venom and prevent its harmful effects. Other treatments may include supportive care, such as pain management, fluid replacement, and oxygen therapy.
Wasp venoms are the toxic secretions produced by wasps, including hornets, yellow jackets, and paper wasps. These venoms contain a complex mixture of proteins, enzymes, and other molecules that can cause a range of physiological effects in humans and other animals. The effects of wasp venom can vary depending on the species of wasp, the amount of venom injected, and the individual's sensitivity to the venom. Common symptoms of wasp venom allergy include hives, swelling, itching, difficulty breathing, and anaphylaxis, a life-threatening allergic reaction that can cause shock and death. In the medical field, wasp venom is studied for its potential therapeutic uses, such as in the treatment of cancer and other diseases. Some of the active components of wasp venom, such as melittin and apamin, have been shown to have anti-inflammatory and anti-cancer properties. However, the use of wasp venom in medicine is still in the experimental stage, and more research is needed to fully understand its potential benefits and risks.
Elapid venoms are the toxic secretions produced by snakes belonging to the family Elapidae, which includes species such as cobras, mambas, and coral snakes. These venoms are highly potent and can cause a range of symptoms, including pain, swelling, paralysis, and even death, depending on the dose and the species of snake involved. Elapid venoms primarily affect the nervous system, causing symptoms such as muscle weakness, difficulty breathing, and loss of consciousness. They can also cause bleeding disorders by affecting the blood's ability to clot, leading to internal and external bleeding. In the medical field, elapid venom is studied for its potential therapeutic uses, such as in the development of new drugs for pain management and the treatment of certain neurological disorders. However, it is also a significant health hazard, and snake bites from elapid snakes are a major cause of morbidity and mortality in many parts of the world. Treatment for elapid snake bites typically involves antivenom therapy, which is designed to neutralize the venom and prevent its harmful effects on the body.
Spider venoms are toxic substances produced by spiders that are used for defense and hunting. These venoms contain a complex mixture of proteins, peptides, and other molecules that can have a wide range of effects on the nervous system, muscles, and other tissues of their prey or predators. In the medical field, spider venoms have been studied for their potential therapeutic applications. Some of the components of spider venom have been found to have analgesic, anti-inflammatory, and anti-cancer properties, and are being investigated as potential treatments for a variety of medical conditions. Spider venoms have also been used in the development of new drugs and therapies. For example, some spider venom toxins have been used to develop drugs that can block pain receptors in the nervous system, while others have been used to develop drugs that can treat conditions such as hypertension and diabetes. However, it is important to note that spider venoms can also be dangerous to humans, and can cause serious health problems if they come into contact with the skin or are injected into the body. In some cases, spider bites can be life-threatening, and medical treatment is necessary to prevent complications.
Scorpion venoms are the toxic secretions produced by scorpions, which are arachnids that have a venomous stinger at the end of their tail. These venoms contain a complex mixture of proteins, peptides, and other molecules that can cause a range of physiological effects in humans and other animals. Scorpion venom can cause a variety of symptoms, depending on the species of scorpion and the amount of venom injected. Some of the most common symptoms include pain, numbness, tingling, muscle spasms, and difficulty breathing. In severe cases, scorpion venom can cause respiratory failure, cardiac arrest, and even death. Scorpion venom has been studied extensively in the medical field, and some of its components have been isolated and characterized. These components have been found to have a range of potential therapeutic applications, including pain relief, anti-inflammatory effects, and the treatment of certain types of cancer. However, scorpion venom is also a significant health hazard, and exposure to it can be dangerous or even deadly. As a result, medical professionals must take appropriate precautions when working with scorpion venom, and individuals who are at risk of exposure should take steps to protect themselves.
Arthropod venoms are toxic substances produced by arthropods, such as insects, spiders, scorpions, and crustaceans, that are injected into their prey or predators during an attack. These venoms contain a complex mixture of proteins, peptides, enzymes, and other molecules that can cause a range of physiological effects in the victim, including pain, inflammation, paralysis, and even death. In the medical field, arthropod venoms are studied for their potential therapeutic and pharmacological properties. Some of the components of arthropod venoms have been found to have anti-inflammatory, analgesic, and anti-cancer effects, and are being investigated as potential treatments for various diseases and conditions. Additionally, arthropod venoms are also used in the development of new drugs and vaccines for the prevention and treatment of arthropod-borne diseases, such as snake bites, spider bites, and insect stings.
Bothrops is a genus of venomous snakes that are found in Central and South America. They are commonly known as pit vipers or lanceheads due to the distinctive shape of their heads and the presence of heat-sensing pits on either side of their nostrils. There are several species of Bothrops, including Bothrops asper, Bothrops atrox, and Bothrops jararaca, which are known to cause significant morbidity and mortality in humans. The venom of Bothrops snakes contains a variety of toxins, including hemotoxic, neurotoxic, and myotoxic components, which can cause a range of symptoms such as pain, swelling, bleeding, muscle weakness, and respiratory failure. In the medical field, Bothrops envenomation is treated with antivenom, which is produced from the venom of other animals, such as horses or sheep, that have been immunized against the venom. Other treatments may include supportive care, such as pain management, fluid replacement, and wound care, depending on the severity of the envenomation.
Fish venoms are toxic substances produced by certain species of fish that can cause harm to humans and other animals. These venoms are typically found in the spines, fins, or teeth of the fish and are used for defense or hunting. Fish venoms can cause a range of symptoms, depending on the species of fish and the amount of venom injected. Some common symptoms include pain, swelling, redness, and numbness at the site of the bite, as well as more serious symptoms such as respiratory distress, cardiac arrhythmias, and even death in severe cases. In the medical field, fish venoms are studied for their potential therapeutic uses, such as in the development of new pain medications or as a source of bioactive compounds for use in drug discovery. However, they are also a significant health concern for people who work with or consume fish, and efforts are made to educate the public about the risks associated with fish bites and stings.
Ant venoms are toxic secretions produced by ants that are used for defense against predators. In the medical field, ant venoms have been studied for their potential therapeutic properties, particularly in the treatment of pain and inflammation. Some ant venoms contain compounds that can block pain receptors in the nervous system, making them useful in the development of new pain medications. Other ant venoms contain compounds that have anti-inflammatory properties, which could be useful in the treatment of conditions such as arthritis and inflammatory bowel disease. Ant venoms have also been studied for their potential use in the treatment of cancer. Some ant venom compounds have been shown to selectively target and kill cancer cells, while leaving healthy cells unharmed. However, it is important to note that ant venoms can also be dangerous and can cause serious harm if not handled properly. As such, the use of ant venoms in medicine is typically restricted to controlled laboratory settings and requires specialized training and equipment.
Mollusk venoms are toxic substances produced by mollusks, such as snails, clams, octopuses, and squids. These venoms can cause a range of symptoms in humans, including pain, swelling, and in severe cases, respiratory failure, paralysis, and death. Mollusk venoms are composed of a complex mixture of proteins, peptides, and other molecules that can interact with various receptors and ion channels in the body, leading to the observed effects. In the medical field, mollusk venoms are studied for their potential therapeutic applications, such as in the development of new drugs for pain management, cancer treatment, and other conditions. However, they are also a significant source of poisoning for humans and animals, particularly in areas where mollusks are commonly consumed as food.
Agkistrodon is a genus of venomous snakes that are commonly known as copperheads. They are found in North and Central America, and are known for their distinctive copper-colored heads. Copperheads are pit vipers and are capable of delivering a venomous bite. The venom from a copperhead bite can cause a range of symptoms, including pain, swelling, and muscle weakness. In severe cases, it can lead to more serious complications such as respiratory failure or kidney failure. Treatment for a copperhead bite typically involves antivenom and supportive care in a hospital setting.
Amphibian venoms are toxic substances produced by certain species of amphibians, such as frogs, toads, and salamanders. These venoms are typically secreted from specialized glands in the skin or from the salivary glands of the amphibian, and they can be used for a variety of purposes, including defense against predators, capturing prey, and as a means of communication with other members of the same species. Amphibian venoms can contain a wide range of toxic compounds, including peptides, proteins, and other molecules. These toxins can have a variety of effects on the body, including pain, paralysis, and even death in some cases. In the medical field, amphibian venoms are being studied for their potential therapeutic applications, such as the development of new pain medications or as a source of compounds with anti-inflammatory or anti-cancer properties. However, it is important to note that many amphibian venoms are also highly toxic and can be dangerous to humans, so they must be handled with caution and under the supervision of a trained professional.
Batroxobin is a medication that is used to treat bleeding disorders. It is a type of blood clotting factor that is derived from the venom of the Bothrops atrox snake. Batroxobin works by activating the blood clotting cascade, which helps to stop bleeding. It is typically administered as an injection and is used to treat conditions such as hemophilia, von Willebrand disease, and other bleeding disorders. Batroxobin is also sometimes used to treat bleeding associated with surgery or other medical procedures.
Snake venoms are complex mixtures of proteins and other molecules that are produced by venom glands in snakes. These venoms are used by snakes as a means of defense against predators or as a tool for capturing prey. The effects of snake venom can vary widely depending on the species of snake and the specific components of the venom. Some snake venoms are primarily hemotoxic, meaning they cause damage to blood vessels and can lead to internal bleeding or organ failure. Other snake venoms are neurotoxic, meaning they affect the nervous system and can cause paralysis or respiratory failure. Still, other snake venoms are myotoxic, meaning they cause damage to muscle tissue. In the medical field, snake venoms are studied for their potential therapeutic uses. Some components of snake venom have been found to have anti-inflammatory, anti-cancer, or anti-viral properties. Additionally, some snake venom components have been used to develop new drugs for the treatment of conditions such as heart disease, stroke, and diabetes. However, it is important to note that snake venom can also be dangerous and can cause serious harm or death if not treated properly.
Snake bites refer to the act of being bitten by a venomous snake. Venomous snakes have specialized teeth that inject venom into their prey or potential predators. The venom can cause a range of symptoms, including pain, swelling, redness, and tissue damage. In severe cases, snake bites can lead to systemic effects such as respiratory failure, cardiovascular collapse, and even death. Treatment for snake bites typically involves antivenom, which neutralizes the venom and can prevent or mitigate the symptoms of the bite. It is important to seek medical attention immediately if you suspect you have been bitten by a venomous snake.
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- The venom of the Midget Faded Rattlesnake is neurotoxic and is considered one of the most potent among Crotalid venoms. (wikipedia.org)
- Neurotoxic venom interrupts brain function and nervous system it produces paralysis or deficiency of muscle control. (ukessays.com)
- The snake venoms that exist are categorized into several types such as hemotoxic venoms, neurotoxic venoms, cytotoxic venoms and myotoxic venoms. (ukessays.com)
- Their venoms act on the blood (hemotoxic) as compared to the venom of elapids which act on the nervous system (neurotoxic). (online-medical-dictionary.org)
- When human is bitten with hemotoxic venom by a snake, the venom decrease blood pressure and increase blood clotting. (ukessays.com)
- red on black, venom lack" is commonly used to distinguish coral snakes from nonvenomous species, but there are many exceptions. (medscape.com)
- Snake venom is adapted saliva that is formed by distinct glands of only certain species of snakes. (ukessays.com)
- Here, by investigating the original transcriptomes from 19 species distributed in eight genera from the Pseudoboini tribe (Dipsadidae: Xenodontinae) and screening among seven additional tribes of Dipsadidae and three additional families of advanced snakes, we discovered that a novel type of venom PLA2, resembling a PLA2-IIE, has been recruited to the venom of some species of the Pseudoboini tribe, where it is a major component. (bvsalud.org)
- Snake venom is a mixture of different enzymes and proteins which many of it not harmless to humans, but some are very toxic. (ukessays.com)
- Snake venom hinders cholinesterase causes loss of muscle control. (ukessays.com)
- Such as Prothrombin Activators which are the best considered snake venom hemostatins. (ukessays.com)
- Thrombin-like enzymes (SVTLE) snake venom is used for fibrinogen breakdown assay and for the fibrinogen dysfunction detection. (ukessays.com)
- As mentioned, snake venom is modified saliva which contains a variety of proteins and enzymes. (ukessays.com)
- Not all snake venoms are dangerous to humans as they contain phosphodiesterase, cholinesterase, hyalurinodase, ATPase. (ukessays.com)
- Snake venoms harbor a wide and diverse array of enzymatic and nonenzymatic toxic components, allowing them to exert myriad effects on their prey. (bvsalud.org)
- Our results demonstrate how relevant phenotypic traits are convergently recruited by different means and from homologous and nonhomologous genes in phylogenetically and ecologically divergent snake groups, possibly optimizing venom composition to overcome diverse adaptative landscapes. (bvsalud.org)
- Annually, snake venom poisoning has 2.5 million victims and 100 000 deaths worldwide. (who.int)
- This shift is similar to what has been observed in other rattlesnake species, although no corresponding shift in venom composition was noted. (wikipedia.org)
- Nevertheless, the latter appears to be restricted to vipers and elapids, as it has never been reported as a major venom component in rear-fanged species. (bvsalud.org)
- Nevertheless, Micrurus species produce a low quantity of venom, which makes it difficult to produce anticoral antivenoms. (bvsalud.org)
- The anti-His-rMdumPLA2 antibodies produced in rabbits recognized native PLA2, the complete venom of M. dumerilii, and a phospholipase from another species of the Micrurus genus. (bvsalud.org)
- which means it's the venom which attacks the central nervous system and brain. (ukessays.com)
- Many cytotoxic types of venom also extent through the body increasing permeability of muscle cells. (ukessays.com)
- In this study, we conducted a proteomic analysis of T. gracilis venom using high-performance liquid chromatography-tandem mass spectrometry and identified 155 toxin proteoforms that belong to 13 viperid venom toxin families. (bvsalud.org)
- During predatory and defensive contexts, Crotalus concolor has been found to inject similar amounts of venom into both mice and lizards, despite the mass of envenomated mice being four times greater than that of the lizards. (wikipedia.org)
- Evolutionary Clues for generating a pan-specific antivenom against crotalid type II venoms [corrected]. (nih.gov)
- 2. The inoculation schedule used in horses to obtain antivenom serum consisted of sc injections of a 7.5 mg venom starting dose in 5.0 ml sterile saline emulsified with an equal volume of Freund's complete adjuvant. (unboundmedicine.com)
- 8. Chemical and functional homology of myotoxin a from prairie rattlesnake venom and crotamine from South American rattlesnake venom. (nih.gov)
- 14. Crotamine and crotalicidin, membrane active peptides from Crotalus durissus terrificus rattlesnake venom, and their structurally-minimized fragments for applications in medicine and biotechnology. (nih.gov)
- Immunization of horses with Crotalus durissus terrificus (South American rattlesnake) venom. (unboundmedicine.com)
- Three Brazilian polyspecific Bothrops antivenoms were compared using standard W.H.O. rodent in vivo and in vitro assays of their ability to neutralize the principal venom activities of pooled whole Bothrops jararaca venom. (ox.ac.uk)
- 3. Comparison of the protective effect of a commercially available western diamondback rattlesnake toxoid vaccine for dogs against envenomation of mice with western diamondback rattlesnake (Crotalus atrox), northern Pacific rattlesnake (Crotalus oreganus oreganus), and southern Pacific rattlesnake (Crotalus oreganus helleri) venom. (nih.gov)
- CROFAB is a sheep-derived antivenin indicated for the management of adult and pediatric patients with North American crotalid envenomation. (nih.gov)
- 5. Quantification of crotamine, a small basic myotoxin, in South American rattlesnake (Crotalus durissus terrificus) venom by enzyme-linked immunosorbent assay with parallel-lines analysis. (nih.gov)
- 1. A comparative study was carried out on horses immunized with Crotalus durissus terrificus venom using four different inoculation procedures, which included the use of Freund's adjuvant, A1(OH)3 and liposomes as adjuvants. (unboundmedicine.com)
- When antigen was emulsified with liposome, the immune serum was ineffective against the lethal effects of C. d. terrificus venom. (unboundmedicine.com)
- The first natural library of venom fractions for Drug Discovery and High Throughput Screening (HTS). (kitoxan.com)
- During predatory and defensive contexts, Crotalus concolor has been found to inject similar amounts of venom into both mice and lizards, despite the mass of envenomated mice being four times greater than that of the lizards. (wikipedia.org)
- 4. Intraspecific venom variation in the medically significant Southern Pacific Rattlesnake (Crotalus oreganus helleri): biodiscovery, clinical and evolutionary implications. (nih.gov)
- 9. Venom variation in hemostasis of the southern Pacific rattlesnake (Crotalus oreganus helleri): isolation of hellerase. (nih.gov)
- On a volume basis, the antivenoms were equally effective in neutralizing lethal activity in mice, and there were only minor differences in their ability to neutralize venom-induced haemorrhage, necrosis and procoagulant activity. (ox.ac.uk)
- Sub-Aim #1: To apply new methods and approaches to the production of recombinant toxins for rare and low-abundance components of crotalid venom. (nih.gov)
- Sub-Aim #2: To develop novel cell-based assays that can be used for the conventional and high-throughput testing of anti-venoms and toxin inhibitory molecules. (nih.gov)