Toxin Sentence Examples
The serum of the animal is tested from time to time against a known amount of toxin, i.e.
By growing this bacillus in broth a toxin is formed which remains in solution and can be separated from the bacilli themselves by filtration.
Then we have the property of adaptation, in which the negative reaction may be changed into a positive; a given toxin may at first repel the cell, but by a gradual process the cell becomes accustomed to such a toxin and will move towards it.
Of such are tetanus and diphtheria, now known to be due to the establishment from without of a local microbic infection, from which focus a toxin is diffused to the nervous matter.
Though an enormous of amount of work has been done on the subject, no important bacterial toxin has as yet been obtained in a pure condition, and, though many of them are probably of proteid nature, even this cannot be asserted with absolute certainty.
In the earlier experiments on smaller animals the potency of the toxin was modified for the first injections, but in preparing antitoxin for therapeutical purposes the toxin is used in its unaltered condition, the horse being the animal usually employed.
The unit of antitoxin in Ehrlich's new standard is the amount requisite to antagonize i oo times the minimum lethal dose of a particular toxin to a guinea-pig of 250 grm.
The secretion of trypsin by the pancreas may therefore be looked upon as the formation of a toxin.
By immunity is meant non-susceptibility to a given disease, or to experimental inoculation with a given bacterium or toxin.
The antitoxic property is developed in a susceptible animal by successive and gradually increasing doses of the toxin.
AdvertisementThe origin of antitoxin is of course merely a part of the general question regarding the production of anti-substances in general, as these all combine in the same way with their homo logous substances and have the same character of g toxin.
In such a case it has been shown that, without the introduction of fresh toxin, new antitoxin appears, and therefore must be produced by the living tissues.
By the introduction of fresh toxin the process is repeated and the regeneration of side-chains is increased.
In other words the substances, which when forming part of the cells fix the toxin to the cells, constitute antitoxin molecules when free in the serum.
Wassermann and Takaki in the case of tetanus, that there do exist in the nervous system molecules with combining affinity for the tetanus toxin.
AdvertisementIf, for example, the brain and spinal cord removed from an animal be bruised and brought into contact with tetanus toxin, a certain amount of the toxicity disappears, as shown by injecting the mixture into another animal.
As a rule it has no action on the corresponding toxin, i.e.
Natural immunity against toxins must be taken into account, and, if Ehrlich's view with regard to toxic action be correct, this may depend upon either the absence of chemical affinity of the living molecules of the tissues for the toxic molecule, or upon insensitiveness to the action of the toxophorous group. It has been shown with regard to the former, for example, that the nervous system of the fowl, which possesses immunity against tetanus toxin, has little combining affinity for it.
Wharfinger states that in chlorosis the specific action of iron is only obtained by administering those inorganic preparations which give a reaction with the ordinary reagents; the iron ions in a state of dissociation act as a catalytic agent, destroying the hypothetical toxin which is the cause of chlorosis.
With regard to the bacillary type, at first both organisms were considered to be identical, and the name bacillus dysenteriae was given to them; but later it was shown that these bacilli are different, both in regard to their cultural characteristics and also in that one (Shiga) gives out a soluble toxin, whilst the other has so far resisted all efforts to discover it.
AdvertisementThe effects of many of these toxins bear a close resemblance to the action of certain wellknown drugs, as in the case of tetanus toxin and strychnine, and are studied by the same methods of observation and research.
In specific germ diseases a similar antitoxin forms, and in cases which recover it counteracts the toxin, while the germs are destroyed by the tissues.
The potatoes were genetically modified to include a toxin - GNA lectin - found in snowdrops to make them resistant to potato aphids.
For example, genes from the bacterium bacillus thuringiensis produce a toxin that kills certain insects.
They now think she could have become intoxicated by a natural toxin found in algae blooms.
AdvertisementThe fusion toxin was active against two insect pests of rice, leaf folder and yellow stem borer.
These bacteria produce a toxin in food which causes a severe illness called botulism which can be fatal.
Welcome to Herbal Fusion - Botox is made from ' botulinum toxin ', a poison produced by the bacterium clostridium botulinum.
Product Overview TransMID TM is a modified diphtheria toxin conjugated to transferrin.
Ama is the most common type of toxin, and is the waste product of incomplete digestion.
The toxin is sometimes present in the milk of cattle which have been given feed containing henbane.
The toxin is released in root exudates from a number of maize hybrids expressing three different transformation events [22] .
The first was developed by chemical modification of a toxin from a marine invertebrate.
Research has shown that rice leafhoppers are controlled by GM rice with Cry1Ab toxin.
This is because kidney beans contain a natural toxin (called lectin) that can cause stomach aches and vomiting.
A detox is a regime designed to reduce the toxin levels in our bodies.
They accidentally produced the toxin MPTP, and this caused the drug users to develop parkinsonism almost overnight.
The toxin released into the soil affected the enzymes of soil microbes, increasing soil acid phosphatase and decreasing soil urease [10] .
Carbon dioxide stimulates production of the toxin in vitro (outside the body ).
Researchers have developed a plant-based vaccine against bacterial Shiga toxin, and show that it is highly protective in mice.
They were alleged to have been involved in a plot to spread ricin, a deadly toxin.
Senate Majority Leader Bill Frist announced progress in decontamination efforts at the Dirksen Senate office building, where the toxin ricin was found Monday.
Baghdad has mobile facilities for producing bacterial toxin BW agents; these facilities can evade detection and are highly survivable.
Investigation of the neuronal aggregate generating seizures in the rat tetanus toxin model of epilepsy.
The duration before onset of symptoms depends on the time taken for ingested toxin to reach the target site.
Protection of frontline workers The release of a Botulinum toxin aerosol will create an exposed zone that presents a high risk of inhaling toxin.
This natural pathogen produces an insecticidal toxin which leaves humans and beneficial insects unaffected.
At a secret meeting in Miami, they furnished him with tiny gelatine capsules filled with botulinum toxin.
The ubiquity of such crops has also allowed the Bt toxin class to become the most widely used in the world.
Once inside a cell the diphtheria toxin interferes with protein synthesis which ultimately kills the cancer cell.
Using the tetanus toxin model we have identified some aspects of the seizures.
We will also use the well-characterised outer leaflet raft marker cholera toxin B subunit in similar studies.
Prior to the research, no proven vaccine existed for the deadly botulism toxin.
Tetanus has been reported to induce lesions in the vagal nuclei, while locally applied toxin may lead to excessive vagal nuclei, while locally applied toxin may lead to excessive vagal activity.
They occupy and destroy the red corpuscles, converting the haemoglobin into melanin; they multiply in the blood by sporulation, and produce accessions of fever by the liberation of a toxin at the time of sporulation (Ross).
Lastly it may be mentioned that when a toxin has some action which can be demonstrated in a test-tube experiment, for example, a dissolving action on red corpuscles, this action may be annulled by previously adding the antitoxin to toxin; in such a case the intervention of the living tissues is excluded.
In all cases the important action is the binding of complement to the bacterium by means of the corresponding immune body; whether or not death of the bacterium occurs, will depend upon its susceptibility to the action of the particular complement, the latter acting like a toxin or digestive ferment.
The development of all antagonistic substances which confer the special character on antimicrobic sera, as well as antitoxins, may be expressed as the formation of bodies with specific combining affinity for the organic substance introduced into the system - toxin, bacterium, red corpuscle, &c., as the case may be.
A mild toxin secreted into the saliva in the mouth helps to stun the prey.
The study focussed on baculovirus containing scorpion toxin because that construction has been most widely studied.
The secreting subpopulation of bacteria would need to be resistant to this toxin in order to survive.
The vaccine encodes a strong immune alert signal from Fragment C from tetanus toxin.
Scientists have now isolated and modified the toxin ricin to eliminate severe side effects without compromising its power to kill tumor cells.
Tetanus has been reported to induce lesions in the vagal nuclei, while locally applied toxin may lead to excessive vagal activity.
It is " likely zucchini grown from saved seed will therefore be more vulnerable to toxin build-up " (LSN 2003).
Although some homeowners may be concerned that the cleaning and disinfect power of their cleaning products would be diminished, green cleaning products are often just as good as their toxin laden counterparts.
The HydroSecure system was developed after the terrorist attacks on September 11, 2001 to help protect water systems from toxin terrorist attacks and is now available for home use.
However, you should remove any eyes or green spots because these portions contain a naturally-occurring toxin called solanine that can cause irregular heartbeats, vomiting and diarrhea in your pet.
Not all organic baby clothing is toxin free.
Squash bugs are a serious problem in the Western Hemisphere and can be found from coast to coast in the U.S. They suck the vital juices from plants and can inject a toxin that causes otherwise healthy plants to wilt, discolor and die.
A tingling sensation may be felt and is often the result of metabolic problems, toxin explosion, infection or traumatic injury.
You will be asked to help investigate and find a way to reduce this toxin from the land.
Tetanus, sometimes called lockjaw, is a disease caused by the toxin of Clostridium tetani.
Botulinum toxin type A (Botox, Dysport) or type B (Myobloc) is injected locally into the affected muscle group to relax the muscles.
Botulinum toxin is made by the bacteria that cause botulism.
However, the amount of botulinum toxin injected to treat spasticity is so small that it would not cause botulism poisoning.
Short-term medications such as lidocaine, a local anesthetic, can be used to assess the potential benefit of botulinum toxin or alcohol and phenol injections.
In 2004, the U.S. Food and Drug Administration approved the use of botulinum toxin (Botox) for treatment of axillary (underarm) hyperhidrosis that resists treatment with topical drugs.
The strain of streptococcus that causes scarlet fever, unlike the one that causes most strep throats, produces an erythrogenic toxin, which causes the skin to flush.
Botulinum toxin (Botox), a highly effective treatment, is injected directly into the affected muscles.
One theory suggests that the bacteria produce some kind of poisonous chemical (toxin).
This toxin is sent into circulation throughout the bloodstream, thus affecting other systems of the body.
Tetanus-A potentially fatal infection caused by a toxin produced by the bacterium Clostridium tetani.
The bacteria usually enter the body through a wound and the toxin they produce affects the central nervous system causing painful and often violent muscular contractions.
These bacteria multiply in areas where there is little oxygen present and produce a toxin that affects the nervous system.
The toxin spreads along the nerves of the body, causing the nerves to fire (react).
The third aspect of treatment involves killing the bacteria producing the toxin using antimicrobial drugs given as an injection.
Fourth, the toxin already circulating in the blood must be neutralized so that it causes no further damage to the nervous system.
After initial exposure to a substance such as wasp sting toxin, the allergic child's immune system becomes sensitized to that allergen.
Shigella also produce a number of toxins (Shiga toxin and others) that increase the amount of fluid secretion by the intestinal tract.
Each type of bacteria has a different incubation period and duration, and all except the botulinum toxin cause inflammation of the intestines and diarrhea.
The severity of symptoms depends on the type of bacteria, the amount consumed, and the individual's general health and sensitivity to the toxin.
Exposure to the botulinum toxin usually occurs while eating contaminated food stored in an airless environment, as in home-canned or commercially canned or vacuum-packed food.
Also, botulinum toxin is a neurotoxin that blocks the ability of motor nerves to release acetylcholine, the neurotransmitter that relays nerve signals to muscles.
Heating canned food to boiling for ten minutes can render the toxin harmless.
However, consuming even a very small amount of the toxin can result in serious illness or death because of lethal neurological complications.
In some cases, the suspected bacteria, virus, or toxin can be identified in the actual food source.
Stopping the diarrhea actually maintains toxin levels in the body for longer periods and may prolong the infection.
Infants, however, cannot receive this antitoxin and are usually treated instead with injections of human botulism immune globulin (BIG), an antiserum that neutralizes the botulinum toxin.
The toxin associated with tetanus, for example, is attacked by IgG1 and IgG3 antibodies; reduced percentages of either immunoglobulin subclass on a child's cells will leave the child unprotected against that specific toxin.
In an experimental procedure, botulinum toxin (Botox) may be injected into the larynx.
This technique appears to be successful but may require repeated injections as the toxin wears off.
Botulism is an acute, progressive condition caused by botulinum toxin, a natural poison produced by the spore-forming bacteria Clostridium botulinum.
The toxin's origin and identity remained vague until Emile van Ermengem (1851-1932), a Belgian professor, isolated Clostridium botulinum in 1895 and identified it as the source of food poisoning.
Although domestic food poisoning is a problem worldwide, concern is growing regarding the use of botulism toxin in biological warfare.
Other members of the Clostridium genus can produce botulinum toxin, namely C. argentinense, C. butyricum, and C. baratii, but these are minor sources.
The spores then germinate, and the growing bacteria produce the deadly botulism toxin.
Domesticated animals such as dogs, cattle, and mink are affected by botulism C toxin, which also affects birds and has caused massive die-offs in domestic bird flocks and wild waterfowl.
Botulism D toxin can cause illness in cattle, and horses succumb to botulism A, B, and C toxin.
There have been no confirmed cases of human or animal botulism linked to the G toxin.
In humans, botulinum toxin latches onto specific proteins in nerve endings and irreversibly destroys them.
Ironically, this action of the botulinum toxin has given it a beneficial niche in the world of medicine.
Medical researchers have discovered that injecting a strictly controlled dose of botulinum toxin into affected muscles inhibits excessive muscle contractions.
Human botulism (caused by botulism toxins A, B, and E) may stem from contaminated food, wound contamination, or the intestinal botulism toxin found in infants.
The spores germinate in the large intestine and, once colonized, toxin is produced and absorbed into the infant's body from the entire intestinal tract.
Wound botulism occurs when Clostridia colonize an infected wound and produce botulinum toxin.
Whether parents are aware of a possible source of the botulism toxin, the suggestive symptoms should not be ignored.
Laboratory tests look for the presence of botulinum toxin or Clostridia in suspected foods and/or the child's blood serum, feces, or other specimens for traces of botulinum toxin or Clostridia.
The antitoxin (effective against toxin types A, B, and E) inactivates only the botulinum toxin that is unattached to nerve endings.
In fact, antibiotic use is discouraged for infants because bacteria could potentially release more toxin into a baby's system as they are killed.
Surgery may be necessary to clean an infected wound (debridement) and remove the source of the bacteria producing the toxin.
It is important to avoid products that contain magnesium, since magnesium enhances the effect of the toxin.
Recovery depends on the nerve endings building new proteins to replace those destroyed by botulinum toxin.
Botox (Botulinum toxin) injections can temporarily control the eye movements, but because of side effects such as double vision and ptosis or drooping of the eyelid, and because it is not a permanent solution, Botox is not used often.
Lice infestations are characterized by intense itching caused by an allergic reaction to a toxin in lice saliva.
In fact, toxin production is related to infections of the bacillus itself with a particular bacteria virus called a phage (from bacteriophage, a virus that infects bacteria).
The bacteria produce a characteristic toxin.
In large enough quantities, the toxin can enter the bloodstream, causing a potentially fatal reaction.
In addition to its metabolism-boosting and fat-burning properties, some brands of these supplements also contain toxin releasing properties, acting as a sort of detox for the body, and may even help with constipation.
The bacteria releases a toxin that causes the skin to break out in a rash.
Botulinum toxin (Botox) is a protein produced from bacteria.
Botox is the brand name for the botulinum toxin, the poison involved in botulism.
In very small doses, however, botulinum toxin can be a useful medicine.
However, botulinum toxin can be very dangerous if not properly prepared.
Its serum in course of time is found to contain something (antitoxin) which has the power of neutralizing the toxin secreted by the organism when parasitical upon the body.
Toxins may thus become so closely keyed into their corresponding atom groups, as for instance in tetanus, that they are no longer free to combine with the antitoxin; or, again, an antitoxin injected before a toxin may anticipate it and, preventing its mischievous adhesion, dismiss it for excretion.
A " dry toxin " is thus obtained, though still in an impure condition.
With regard to toxin formation the following general statements may be made.
Thus, to mention examples, diphtheria toxin produces inflammatory oedema which may be followed by necrosis; dead tubercle bacilli give rise to a tubercle-like nodule, &c. Furthermore, a bacillus may give rise to more than one toxic body, either as stages in one process of change or as distinct products.
Thus paralysis following diphtheria is in all probability due to a different toxin from that which causes the acute symptoms of poisoning or possibly to a modification of it sometimes formed in specially large amount.
These facts show the great difficulty of the problem, which is probably insoluble by present methods of analysis; the only test, in fact, for the existence of a toxin is its physiological effect.
It is also to be noted that, as in the case of poisons of known constitution, each toxin has a minimum lethal dose which is proportionate to the weight of the animal and which can be ascertained with a fair degree of accuracy.
It consists in all probability of disturbance, by means of the chemical affinities of the toxin, of the highly complicated molecules of living cells.
In other cases such changes cannot be detected, and the only evidence of their occurrence may be the associated symptoms. The very important work of Ehrlich on diphtheria toxin shows that in the molecule of toxin there are at least two chief atom groups - one, the " haptophorous," by which the toxin molecule is attached to the cell protoplasm; and the other the " toxophorous," which has a ferment-like action on the living molecule, producing a disturbance which results in the toxic symptoms. On this theory, susceptibility to a toxin will imply both a chemical affinity of certain tissues for the toxin molecule and also sensitiveness to its actions, and, furthermore, non-susceptibility may result from the absence of either of these two properties.
It is to be noted that there is no fixed relation between toxin production and bacterial multiplication in the body, some of the organisms most active as toxin producers having comparatively little power of invading the tissues.
Again, in certain cases the toxin has a special affinity for certain tissues.
A third method is by injections of the separated toxins of a bacterium, the resulting immunity being not only against the toxin, but, so far as present knowledge shows, also against the living organism.
In the development of toxin-immunity the doses, small at first, are gradually increased in successive inoculations; or, as in the case of very active toxins, the initial injections are made with toxin modified by heat or by the addition of various chemical substances.
In order that the immunity may reach a high degree, either the bacterium in a very virulent state or a large dose of toxin must ultimately be used in the injections.
So far as bacterial immunity is concerned, the anti-serum exerts its action either on the toxin or on the bacterium itself; that is, its action is either antitoxic or anti-bacterial.
The antitoxic serum when injected enttinoxic previously to the toxin also confers immunity (passive) against it; when injected after the toxin it has within certain limits a curative action, though in this case its dose requires to be large.
Kanthack and Cobbett, that in certain instances the toxin can be made to pass through a gelatine membrane, whereas the antitoxin cannot, its molecules being of larger size.
If, however, toxin be mixed with antitoxin for some time, it can no longer be passed through, presumably because it has become combined with the antitoxin.
In view of the fact that antitoxin has a direct action on toxin, we may say that theoretically this may take place in one of two ways.
It may produce a disintegration of the toxin molecule, or it may combine with it to produce a body whose combining affinities are satisfied.
His view as to the dual composition of the toxin molecule has already been mentioned, and it is evident that if the haptophorous or combining group has its affinity satisfied by union with antitoxin, the toxin will no longer combine with living cells, and will thus be rendered harmless.
One other important fact in support of what has been stated is that a toxin may have its toxic action diminished, and may still require the same amount of antitoxin as previously for neutralization.
There is, however,, still dispute with regard to the exact nature of the union of toxin and antitoxin.
He found, however, that if he took the largest amount of toxin which was just neutralized by a given amount of antitoxin, much more than a single dose of toxin had to be added before a single dose was left free.
This result, which is usually known now as the " Ehrlich phenomenon," was explained by him on the supposition that the " toxin " does not represent molecules which are all the same, but contains molecules of different degrees of combining affinity and of toxic action.
Arrhenius, who hold that the union of toxin and antitoxin is comparatively loose, and belongs to the classof reversible actions, being comparable in fact with the union of a weak acid and base.
If such were the condition there would always be a certain amount both of free toxin and of free antitoxin in the mixture, and in this case also considerably more than a dose of toxin would have to be added to a " neutral mixture " before the amount of free toxin was increased by a dose, that is, before the mixture became lethal.
Still another view, advocated by Bordet, is that the union of toxin and antitoxin is rather of physical than of strictly chemical nature, and represents an interaction of colloidal substances, a sort of molecular deposition by which the smaller toxin molecule becomes entangled in the larger molecule of antitoxin.
We are probably safe in saying, however, that the molecules of a toxin are not identical but vary in the degree of their combining affinities, and also in their toxic action, and that, while in some cases the combination of anti-substances has been shown to be reversible, we are far from being able to say that this is a general law.
It is by means of such side-chains that toxin molecules are attached to the protoplasm, so that the living molecules are brought under the action of the toxophorous groups of the toxins.
But the evidence in favour of the view that tapeworms normally excrete toxin into the body of their host in such amount as to occasion disease is not generally accepted as conclusive.
Little is known of its toxic action; only a weak toxin has been obtained from cultures.
The serum is then removed and its anti-toxic power tested by ascertaining the amount necessary to counteract a given amount of active toxin in a guinea-pig of a certain size, the standard weight being three hundred grammes.
In fact, a splitting appears to take place in the process of secretion somewhat resembling that which takes place in the formation of a toxin and anti-toxin.
In recent years the relations of toxin and antitoxin, still obscure, have been the subject of much study and controversy.
So that when a " toxin " is spoken of, a mixture with other organic substances is usually implied.
Or the toxin may be precipitated with other organic substances, purified to a certain extent byre-solution, re-precipitation, &c., and desiccated.
It has been found, for example, that a toxin may pass through such a filter while an antitoxin may not.
Attempts to get a pure toxin by repeated precipitation and solution have resulted in the production of a whitish amorphous powder with highly toxic properties.
The question has, however, been raised whether the toxin is really itself a proteid, or whether it is not merely carried down with the precipitate.
There is of course the possibility in this case that the toxin was a proteid, but was in so small amount that it escaped detection.
It may also be mentioned that many toxins have now been obtained by growing the particular organism in a proteid-free medium, a fact which shows that if the toxin is a proteid it may be formed synthetically by the bacterium as well as by modification of proteid already present.
According to this view, then, a part at least of the directly toxic substance is produced in the living body by enzymes present in the so-called toxin obtained from the bacterial culture.
The term " antitoxic " signifies that serum has the power of neutralizing the action of the toxin, as is shown by mixing them together outside the body and then injecting them into an animal.
It may be stated that while in certain instances the union of toxin and antitoxin may be reversible, all the facts established cannot be explained on this simple hypothesis of reversible action.