Ant venoms. Medical search

Ant Venoms: Venoms from the superfamily Formicoidea, Ants. They may contain protein factors and toxins, histamine, enzymes, and alkaloids and are often allergenic or immunogenic.Ants: Insects of the family Formicidae, very common and widespread, probably the most successful of all the insect groups. All ants are social insects, and most colonies contain three castes, queens, males, and workers. Their habits are often very elaborate and a great many studies have been made of ant behavior. Ants produce a number of secretions that function in offense, defense, and communication. (From Borror, et al., An Introduction to the Study of Insects, 4th ed, p676)Encyclopedias as Topic: Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)Predatory Behavior: Instinctual behavior pattern in which food is obtained by killing and consuming other species.Crotalid Venoms: Venoms from snakes of the subfamily Crotalinae or pit vipers, found mostly in the Americas. They include the rattlesnake, cottonmouth, fer-de-lance, bushmaster, and American copperhead. Their venoms contain nontoxic proteins, cardio-, hemo-, cyto-, and neurotoxins, and many enzymes, especially phospholipases A. Many of the toxins have been characterized.Bee Venoms: Venoms obtained from Apis mellifera (honey bee) and related species. They contain various enzymes, polypeptide toxins, and other substances, some of which are allergenic or immunogenic or both. These venoms were formerly used in rheumatism to stimulate the pituitary-adrenal system.Venoms: Poisonous animal secretions forming fluid mixtures of many different enzymes, toxins, and other substances. These substances are produced in specialized glands and secreted through specialized delivery systems (nematocysts, spines, fangs, etc.) for disabling prey or predator.Helicobacter pylori: A spiral bacterium active as a human gastric pathogen. It is a gram-negative, urease-positive, curved or slightly spiral organism initially isolated in 1982 from patients with lesions of gastritis or peptic ulcers in Western Australia. Helicobacter pylori was originally classified in the genus CAMPYLOBACTER, but RNA sequencing, cellular fatty acid profiles, growth patterns, and other taxonomic characteristics indicate that the micro-organism should be included in the genus HELICOBACTER. It has been officially transferred to Helicobacter gen. nov. (see Int J Syst Bacteriol 1989 Oct;39(4):297-405).Stomach Ulcer: Ulceration of the GASTRIC MUCOSA due to contact with GASTRIC JUICE. It is often associated with HELICOBACTER PYLORI infection or consumption of nonsteroidal anti-inflammatory drugs (NSAIDS).Gastric Mucosa: Lining of the STOMACH, consisting of an inner EPITHELIUM, a middle LAMINA PROPRIA, and an outer MUSCULARIS MUCOSAE. The surface cells produce MUCUS that protects the stomach from attack by digestive acid and enzymes. When the epithelium invaginates into the LAMINA PROPRIA at various region of the stomach (CARDIA; GASTRIC FUNDUS; and PYLORUS), different tubular gastric glands are formed. These glands consist of cells that secrete mucus, enzymes, HYDROCHLORIC ACID, or hormones.Helicobacter Infections: Infections with organisms of the genus HELICOBACTER, particularly, in humans, HELICOBACTER PYLORI. The clinical manifestations are focused in the stomach, usually the gastric mucosa and antrum, and the upper duodenum. This infection plays a major role in the pathogenesis of type B gastritis and peptic ulcer disease.Peru Anti-Bacterial Agents: Substances that reduce the growth or reproduction of BACTERIA.Gastritis: Inflammation of the GASTRIC MUCOSA, a lesion observed in a number of unrelated disorders.Wounds, Gunshot: Disruption of structural continuity of the body as a result of the discharge of firearms.Forensic Ballistics: The science of studying projectiles in motion, ballistics, being applied to law. Ballistics on firearm projectiles, such as bullets, include the study of what happens inside the weapon, during the flight of the projectile, and when the projectile strikes the target, such as body tissue.Crotoxin: A specific complex of toxic proteins from the venom of Crotalus durissus terrificus (South American rattlesnake). It can be separated into a phospholipase A and crotapotin fragment; the latter consists of three different amino acid chains, potentiates the enzyme, and is specifically neurotoxic.Bites and Stings Insect Bites and Stings: Bites and stings inflicted by insects.Diptera: An order of the class Insecta. Wings, when present, number two and distinguish Diptera from other so-called flies, while the halteres, or reduced hindwings, separate Diptera from other insects with one pair of wings. The order includes the families Calliphoridae, Oestridae, Phoridae, SARCOPHAGIDAE, Scatophagidae, Sciaridae, SIMULIIDAE, Tabanidae, Therevidae, Trypetidae, CERATOPOGONIDAE; CHIRONOMIDAE; CULICIDAE; DROSOPHILIDAE; GLOSSINIDAE; MUSCIDAE; TEPHRITIDAE; and PSYCHODIDAE. The larval form of Diptera species are called maggots (see LARVA).Arthropod Antennae: Paired sense organs connected to the anterior segments of ARTHROPODS that help them navigate through the environment.Biological Control Agents: Organisms, biological agents, or biologically-derived agents used strategically for their positive or adverse effect on the physiology and/or reproductive health of other organisms.Fires Pheromones: Chemical substances, excreted by an organism into the environment, that elicit behavioral or physiological responses from other organisms of the same species. Perception of these chemical signals may be olfactory or by contact.Vincamine: A major alkaloid of Vinca minor L., Apocynaceae. It has been used therapeutically as a vasodilator and antihypertensive agent, particularly in cerebrovascular disorders.Harringtonines: Tetracyclic spiro-BENZAZEPINES isolated from the seeds of CEPHALOTAXUS. They are esters of the alkaloid cephalotaxine and may be effective as antineoplastic agents.Alkaloids: Organic nitrogenous bases. Many alkaloids of medical importance occur in the animal and vegetable kingdoms, and some have been synthesized. (Grant & Hackh's Chemical Dictionary, 5th ed)Bromine: A halogen with the atomic symbol Br, atomic number 36, and atomic weight 79.904. It is a volatile reddish-brown liquid that gives off suffocating vapors, is corrosive to the skin, and may cause severe gastroenteritis if ingested.Ergot Alkaloids: Alkaloids originally isolated from the ergot fungus Claviceps purpurea (Hypocreaceae). They include compounds that are structurally related to ergoline (ERGOLINES) and ergotamine (ERGOTAMINES). Many of the ergot alkaloids act as alpha-adrenergic antagonists.Vinca Alkaloids: A group of indole-indoline dimers which are ALKALOIDS obtained from the VINCA genus of plants. They inhibit polymerization of TUBULIN into MICROTUBULES thus blocking spindle formation and arresting cells in METAPHASE. They are some of the most useful ANTINEOPLASTIC AGENTS.Morphine: The principal alkaloid in opium and the prototype opiate analgesic and narcotic. Morphine has widespread effects in the central nervous system and on smooth muscle.Organoplatinum Compounds: Organic compounds which contain platinum as an integral part of the molecule.Peripheral Nervous System Diseases: Diseases of the peripheral nerves external to the brain and spinal cord, which includes diseases of the nerve roots, ganglia, plexi, autonomic nerves, sensory nerves, and motor nerves.Acupuncture Therapy: Treatment of disease by inserting needles along specific pathways or meridians. The placement varies with the disease being treated. It is sometimes used in conjunction with heat, moxibustion, acupressure, or electric stimulation.Hyperalgesia: An increased sensation of pain or discomfort produced by mimimally noxious stimuli due to damage to soft tissue containing NOCICEPTORS or injury to a peripheral nerve.Bees: Insect members of the superfamily Apoidea, found almost everywhere, particularly on flowers. About 3500 species occur in North America. They differ from most WASPS in that their young are fed honey and pollen rather than animal food.Anaphylaxis: An acute hypersensitivity reaction due to exposure to a previously encountered ANTIGEN. The reaction may include rapidly progressing URTICARIA, respiratory distress, vascular collapse, systemic SHOCK, and death.Food Hypersensitivity: Gastrointestinal disturbances, skin eruptions, or shock due to allergic reactions to allergens in food.Nuts: Botanically, a type of single-seeded fruit in which the pericarp enclosing the seed is a hard woody shell. In common usage the term is used loosely for any hard, oil-rich kernel. Of those commonly eaten, only hazel, filbert, and chestnut are strictly nuts. Walnuts, pecans, almonds, and coconuts are really drupes. Brazil nuts, pistachios, macadamias, and cashews are really seeds with a hard shell derived from the testa rather than the pericarp.Emergencies: Situations or conditions requiring immediate intervention to avoid serious adverse results.Desensitization, Immunologic: Immunosuppression by the administration of increasing doses of antigen. Though the exact mechanism is not clear, the therapy results in an increase in serum levels of allergen-specific IMMUNOGLOBULIN G, suppression of specific IgE, and an increase in suppressor T-cell activity.Indigo Carmine: Indolesulfonic acid used as a dye in renal function testing for the detection of nitrates and chlorates, and in the testing of milk.Books Saudi ArabiaBook SelectionBook Reviews as Topic: Critical analyses of books or other monographic works.Anatomic Landmarks: Reference points located by visual inspection, palpation, or computer assistance, that are useful in localizing structures on or within the human body.Rare Books Software: Sequential operating programs and data which instruct the functioning of a digital computer.Internet: A loose confederation of computer communication networks around the world. The networks that make up the Internet are connected through several backbone networks. The Internet grew out of the US Government ARPAnet project and was designed to facilitate information exchange.Algorithms: A procedure consisting of a sequence of algebraic formulas and/or logical steps to calculate or determine a given task.User-Computer Interface: The portion of an interactive computer program that issues messages to and receives commands from a user.Pseudohypoparathyroidism: A hereditary syndrome clinically similar to HYPOPARATHYROIDISM. It is characterized by HYPOCALCEMIA; HYPERPHOSPHATEMIA; and associated skeletal development impairment and caused by failure of response to PARATHYROID HORMONE rather than deficiencies. A severe form with resistance to multiple hormones is referred to as Type 1a and is associated with maternal mutant allele of the ALPHA CHAIN OF STIMULATORY G PROTEIN.Skin: The outer covering of the body that protects it from the environment. It is composed of the DERMIS and the EPIDERMIS.Computational Biology: A field of biology concerned with the development of techniques for the collection and manipulation of biological data, and the use of such data to make biological discoveries or predictions. This field encompasses all computational methods and theories for solving biological problems including manipulation of models and datasets.

Analysis of ectatomin action on cell membranes. (1/17)

Ectatomin (m = 7928 Da) is a toxic component from the Ectatomma tuberculatum ant venom containing two homologous polypeptide chains (37 and 34 residues) linked to each other by a disulfide bond. In aqueous solution it forms a four alpha-helix bundle. At concentrations of 0.05-0.1 microm, ectatomin forms channels in cellular and artificial bilayer membranes. Immunochemical analysis of the intracellular distribution of ectatomin showed that the toxin gets efficiently inserted into the plasma membrane at a concentration of 5 x 10-7 m and does not penetrate inside the cell. The effect of ectatomin on cardiac L-type calcium current was studied. Calcium currents (ICa) in isolated rat cardiac ventricular myocytes were measured using the whole-cell perforated patch-clamp technique. It was shown that ectatomin at concentrations of 0.01-10 nm inhibited ICa after a latency of few seconds. ICa was decreased twofold by 10 nm ectatomin. However, the most prominent effect of ectatomin was observed after stimulation of ICa by isoproterenol, an agonist of beta-adrenoreceptors, or forskolin, a stimulator of adenylate cyclase. At a concentration of 1 nm, ectatomin abolished the isoproterenol- and forskolin-sensitive components of ICa. The inhibitory effect of ectatomin was partially reversed by subsequent application of 2 microm of forskolin, whereas subsequent isoproterenol application did not produce the same effect. (+info)

Ponericins, new antibacterial and insecticidal peptides from the venom of the ant Pachycondyla goeldii. (2/17)

The antimicrobial, insecticidal, and hemolytic properties of peptides isolated from the venom of the predatory ant Pachycondyla goeldii, a member of the subfamily Ponerinae, were investigated. Fifteen novel peptides, named ponericins, exhibiting antibacterial and insecticidal properties were purified, and their amino acid sequences were characterized. According to their primary structure similarities, they can be classified into three families: ponericin G, W, and L. Ponericins share high sequence similarities with known peptides: ponericins G with cecropin-like peptides, ponericins W with gaegurins and melittin, and ponericins L with dermaseptins. Ten peptides were synthesized for further analysis. Their antimicrobial activities against Gram-positive and Gram-negative bacteria strains were analyzed together with their insecticidal activities against cricket larvae and their hemolytic activities. Interestingly, within each of the three families, several peptides present differences in their biological activities. The comparison of the structural features of ponericins with those of well-studied peptides suggests that the ponericins may adopt an amphipathic alpha-helical structure in polar environments, such as cell membranes. In the venom, the estimated peptide concentrations appear to be compatible with an antibacterial activity in vivo. This suggests that in the ant colony, the peptides exhibit a defensive role against microbial pathogens arising from prey introduction and/or ingestion. (+info)

A case of anaphylaxis by ant (Ectomomyrmex spp.) venom and measurements of specific IgE and IgG subclasses. (3/17)

Hypersensitivity to the stings of the Hymenoptera has been described since antiquity. The hypersensitive reactions to insect stings vary from minor skin reactions to severe and sometimes fatal anaphylaxis. Concerns about sting hypersensitivity have been increasing because of many incidents of allergic reactions of patients to the fire ant in the southern area of the United States as well as the harvester ant in some areas. We experienced one unique case with severe allergic reactions by ant of the Ectomomyrmex spp. of the subfamily Ponerinae, which is not a harvester ant. For three years the patient had been suffering from generalized allergic reactions such as anaphylaxis after the ant stings four-five attacks in a year. We determined that her reactions were due to specific IgE mediated type I hypersensitivity by the detection of a high level of specific IgE to the ant venom in her serum. The high level of specific IgG4 to the ant venom was also noted in her serum, however, the role of ant venom IgG4 was not clearly determined. (+info)

Poneratoxin, a neurotoxin from ant venom. Structure and expression in insect cells and construction of a bio-insecticide. (4/17)

Poneratoxin is a small neuropeptide found in the venom of the ant Paraponera clavata. It is stored in the venom reservoir as an inactive 25-residue peptide. Here we describe both chemically synthesized poneratoxin and poneratoxin obtained by expression in insect cells. When expressed in insect cells, poneratoxin was observed attached to cell membranes. Both synthetic and recombinant ponerotoxins were soluble below pH 4.5. The structure of synthetic poneratoxin was characterized by circular dichroism and solved by nuclear magnetic resonance. In an environment imitating a lipid bilayer, at pH within the range of insect hemolymph, synthetic poneratoxin has a V shape, with two alpha-helices connected by a beta-turn. Insect larvae were paralyzed by injection of either of the purified toxins, with the recombinant one acting faster. The recombinant toxin-producing baculovirus reduced the average survival time of the insect host by 25 h compared with unmodified virus. Mass spectrometry analysis showed that the recombinant toxin has an N-terminal 21-residue extension, possibly improving its stability and/or stabilizing the membrane-bound state. The potential use of poneratoxin for the construction of biological insecticide is discussed. (+info)

Description of an injury in a human caused by a false tocandira (Dinoponera gigantea, Perty, 1833) with a revision on folkloric, pharmacological and clinical aspects of the giant ants of the genera Paraponera and Dinoponera (sub-family Ponerinae). (5/17)

The authors observed an injury caused by the sting of a false tocandira ant in the hand of an amateur fisherman and they describe the clinical findings and the evolution of the envenoming, which presented an acute and violent pain, cold sweating, nausea, a vomiting episode, malaise, tachycardia and left axillary's lymphadenopathy. About three hours after the accident, still feeling intense pain in the place of the sting, he presented an episode of great amount of blood in the feces with no history of digestive, hematological or vascular problems. The intense pain decreased after eight hours, but the place stayed moderately painful for about 24 hours. In that moment, he presented small grade of local edema and erythema. The authors still present the folkloric, pharmacological and clinical aspects related to the tocandiras stings, a very interesting family of ants, which presents the largest and more venomous ants of the world. (+info)

Insect venom hypersensitivity: experience in a clinical immunology/allergy service in Singapore. (6/17)

INTRODUCTION: To study the profile of patients with allergy to the venom of insect stings. METHODS: 31 consecutive cases referred to our clinical immunology/allergy outpatient service from June 1, 1998 to June 30, 2002 were reviewed. RESULTS: These patients comprised 3.5 percent of 889 cases referred during the study period. Their mean age was 28.8 +/- 10.5 (range 19-57) years and the majority were males (90.3 percent). Of these, 20 (64.5 percent) were Chinese, four (12.9 percent) were Malays and seven (22.6 percent) were of other races. 19 patients (61.3 percent) were men from the uniformed services including 12 (63.2 percent) full-time National Servicemen. 71 percent (22 patients) were stung for the first time. Urticaria (22 cases, 71.0 percent), dyspnoea (13, 41.9 percent), angioedema (12, 38.7 percent) and syncope (ten, 32.3 percent) were the most common manifestations of insect allergy. Anaphylaxis occurred in 22 (71.0 percent) cases, constituting 30.1 percent of all cases of anaphylaxis referred to our service during the study period. Although the causative insect was identified as honeybee (12, 38.7 percent), ant (four, 12.9 percent), wasp (three, 9.7 percent), and fire ant (two, 6.5 percent) by the majority of patients, ten (32.2 percent) patients were unable to identify the causative insect. The two patients stung by fire ants were Americans working in Singapore who had been stung while in the United States. Among those with anaphylaxis, honeybee, wasp and fire ant venom, for which specific immunotherapy is available, were identified as the cause in 40.9 percent, 4.5 percent, and 4.5 percent, respectively. CONCLUSION: Insect venom hypersensitivity made up 3.5 percent of allergy/immunology referrals and 32.8 percent of cases of anaphylaxis referred to our institution. The majority were military servicemen who developed allergic reactions during the course of duty. The inability to identify the causative insect in 50 percent with sting anaphylaxis limits the role of specific immunotherapy in our patients. (+info)

Anaphylaxis caused by imported red fire ant stings in Malaga, Spain. (7/17)

A 27-year-old woman suffered from anaphylaxis after being stung by Solenopsis invicta ants while she was handling wood from South America. The patient reported no previous adverse reactions to stings by other hymenopteran species. Intradermal skin tests with hymenoptera venom (Vespula vulgaris, Polistes species, Apis melifera) were negative. Serum specific immunoglobulin (Ig) E yielded positive results for S invicta (5.28 kU/L) and negative results for A melifera, Ves v 5 and Pol a 5. Immunodetection assays showed the presence of serum IgE against the Sol i 2 allergen. The patient had probably been stung previously although inadvertently by red fire ants while she handled infested wood from South America, and precautionary measures are thus advisable when this material is to be handled. To our knowledge this is the first case of anaphylaxis from red fire ant stings reported in Europe. (+info)

My journey to the ants. (8/17)

In this paper, I review the strange, unplanned and unexpected journey I have had with Solenopsis invicta, the imported fire ant. Through serendipity, good fortune and repeated invenomation, I have come to count as collaborators a number of entomologists, toxicologists, allergists and immunologists who have guided me on this journey to the ants. We now understand the mechanisms for the cutaneous reactions experienced by 50% of the exposed population stung per year, as well as the immunologic and toxicologic properties of the ants unique venom. Allergen immunotherapy to fire ant extracts has been demonstrated to protect patients from repeat anaphylaxis. Methods have been developed to prevent and treat massive sting attacks on frail elders, including those in residential and medical facilities. The potential beneficial effects of venom components are under investigation. And yes, the journey and the stings continue. (+info)