Euscorpius scorpions are relatively harmless with poison that has effects similar to a mosquito bite.
and discomfort but for those with a bee venom allergy the consequences can be devastating:
In a paper to be published online Oct 24 in Immunity the researchers show that mice injected with a small dose of bee venom were later resistant to a potentially lethal dose of the same venom.
The study is the first experimental evidence that the same immune response involved in allergies may have evolved to serve a protective role against toxins.
The study builds on earlier work by the researchers characterizing the innate immune response to snake venom and honeybee venom.
Innate immune responses occur in subjects exposed to a foreign substance such as a pathogen or a toxic material like venom for the first time.
when a pathogen or toxin intrudes. In a previous study the researchers found that mast cells produce enzymes that can detoxify components of snake venom
and that mast cells can also enhance innate resistance to honeybee venom. Such innate immune responses do not require prior immunization or the development of specific antibodies.
By contrast during an adaptive immune response the immune system generates antibodies that recognize the invading pathogen or toxin;
this process makes it possible to vaccinate against infectious diseases. Adaptive immunity is usually a faster more specific and more effective form of defense than innate immunity.
This idea known as the toxin hypothesis of allergy was proposed first by Margie Profet in 1991
To find out whether adaptive immune responses could help mice resist bee venom Marichal and Starkl first injected mice with a low dose of venom equivalent to one or two stings.
The mice developed more venom-specific immune cells and higher levels of Ige antibodies against the venom than control mice injected with a salt solution.
Three weeks later they injected both groups of mice with a potentially lethal dose of venom similar to five bee stings.
The immunized mice had less hypothermia and were three times more likely to survive than the control mice.
Moreover they did not develop the anaphylactic reactions characteristic of severe allergies. To determine whether Ige antibodies were required for this protection the team tested mice with three types of mutations:
In all three groups of mutant mice pre-immunization with a low dose of bee venom did not confer protection against a lethal dose suggesting that the protection depends on Ige signaling and mast cell activation.
Pre-immunization with a low dose of venom from the Russell's viper also protected mice from a higher dose of venom from this snake which is one of the big four species responsible for most snakebite
So the researchers believe the response could be generalized to different types of toxic venoms. Our findings support the hypothesis that this kind of venom-specific Ige-associated adaptive immune response developed at least in evolutionary terms to protect the host against potentially toxic amounts of venom such as would happen
if the animal encountered a whole nest of bees or in the event of a snakebite said Stephen Galli MD professor and chair of pathology and the co-senior author of the study.
or reptile venom but it would be unthinkable to test lethal doses of venom in humans.
Reptile and arthropod venoms are complex chemical cocktails. Some venom components have evolved to mimic chemicals made by the human body such as endothelin-1
which causes blood vessels to constrict during bacterial infections. At the same time mammals have evolved immune responses to venom which in some cases escalate into maladaptive allergic reactions.
We experience allergies in a much cleaner world where we don't have the same threats of venomous creatures
This is the first evidence that we know of indicating that Ige-associated'allergic-type'immune responses can actually reduce the toxicity of naturally occurring venoms.
They may range further than the females picking up more toxins as they go. Or the females might transfer some of the contaminants to their offspring during nursing as previous research suggests.
#Foods toxins that can cause cervical, liver cancermexican scientists identified and quantified the amount of aflatoxins (carcinogenic) in food such as corn tortilla rice chili pepper processed sauces chicken breast
and eggs and revealed its relationship with cervical and liver cancer in humans. The research won the National Award in Food Science
It explains that both types of cancer can be originated by the ingestion of food contaminated with aflatoxins produced by the fungi Aspergilus flavus and A. parasiticus.
Magda Carvajal Moreno from the Biology Institute at UNAM (National Autonomous University of Mexico) and head of the research explained that this is the first time both conditions are related with the presence of aflatoxins the most frequent carcinogenic we ate daily she said.
and found that aflatoxins are present in chicken breast gizzard liver and eggs-white and yolk.
and cervical cancer in humans therefore aflatoxins are a very important factor in triggering this diseases.
This research is the first in the world to report that cervical cancer can also be caused by ingesting aflatoxin contaminated food.
The specialist clarified that Human Papillomavirus is more carcinogenic and prone to trigger cervical cancer than aflatoxins.
The toxins-the researcher said-are in the water soil and airborne the fungi that produce them are an olive green mold that can be found in refrigerators besides they are very resistant to high temperatures.
or milligrams of aflatoxin that accumulate over the years in DNA decreased resistance in people
which would control the production of the toxin. Also vary the foods one ingests and preferably consume wheat tortilla and fish as well as antioxidants.
if there is an association with aflatoxins. These initiatives are promoted by the PNCTA (National Award in Food Science and Technology.
Earlier sequencing of the Calas bacteria genome showed that there were no toxins or enzymes that would destroy plant cell walls
Perfect#Except when insect populations develop resistance to the toxin! To date management strategies implemented to delay the evolution of resistance have been successful.
Notwithstanding the success of these strategies IRD scientists and their South african partners have revealed now that a major pest of maize the moth Busseola fusca has developed an unusual defense mechanism against Bt toxin in South africa.
Both the leaves and stems of Bt maize produce this toxin which destroys the gut of any moth larvae eating the plant.
the aim being to maintain pockets of insects that remain susceptible to the toxin. In line with other known cases of Bt-resistance resistance in Busseola fusca was expected to involve modification of the cells in the gut wall
which prevents the toxin from binding. Crucially this type of adaptation is inherited recessively: both parents must be resistant to produce fully resistant offspring.
Implicationsin South africa most farmers are still cultivating single-toxin Bt maize. In many cases they need to apply at least one pesticide spray which makes planting of Bt varieties less attractive.
In the medium term single-toxin Bt maize is being replaced progressively by a stacked variety producing two different toxins
but in a worst case scenario one cannot exclude that Busseola fusca could also quickly adapt to varieties expressing more than one toxin.
Such perspectives could include a more diverse array of toxins for the control of pest populations possibly supplemented with a biological component such as pathogenic fungi or parasitic wasps.
Supernatants (washings) from bacterial cultures had similar effects suggesting that the bacteria were secreting biomolecules that poisoned nonfarmers preventing them from eating the farmers'crops.
#Australian tarantula venom contains novel insecticide against agricultural pestsspider venoms are usually toxic when injected into prey
but a new protein discovered in the venom of Australian tarantulas can also kill prey insects that consume the venom orally.
Isolated peptides from the venom of spiders or other venomous insectivorous animals such as centipedes and scorpions may have the potential to serve as bioinsecticides.
King elaborates The breakthrough discovery that spider toxins can have oral activity has implications not only for their use as bioinsecticides
but also for spider-venom peptides that are being considered for therapeutic use. Story Source: The above story is provided based on materials by Public library of Science.
But it also creates a vulnerability to environmental toxins giving bedbugs an unusually large surface area where pesticides can enter their bodies.
In case insecticides slip past the armor other genes kick in to prevent the toxins from attacking the nervous system.
The large heavy and poisonous seeds surrounded by a fleshy and nontoxic fruit-like layer seem well adapted to being swallowed occasionally whole en masse by megafauna
#Bee venom: Biophysicists zoom in on pore-forming toxina new study by Rice university biophysicists offers the most comprehensive picture yet of the molecular-level action of melittin the principal toxin in bee venom.
The research could aid in the development of new drugs that use a similar mechanism as melittin's to attack cancer and bacteria.
of which use venoms to sting their prey but instead are scavengers like those that pick up crumbs off kitchen floors
which they could not assign to any known species. As it turned out it was indeed a hitherto undescribed species of poison dart frog
Mosquitoes don't die from the toxin per se. They die from sodium overdose. With the door jammed wide open their cells gulp down sodium which overexcites their nervous system and eventually leads to paralysis and death.
and increase the activity of genes involved in breaking down toxins most likely to cope with the insecticide.
and not letting a cell get poisoned by badly folded or aggregated proteins he said.
and not letting a cell get poisoned by badly folded or aggregated proteins he said.
#Illegal marijuana grows threaten fishers in the southern Sierra Nevadarat poison used on illegal marijuana grows is killing fishers in the southern Sierra nevada according to a recent study conducted by a team of scientists from the U s. Forest Service's Pacific
The authors speculated that the most likely source of the poisons was the illegal marijuana grows found throughout the Sierra nevada.
The researchers deduced that illegal marijuana grows are a likely source of the poison because the fishers in this study were radio-tracked and many were observed not venturing into rural urban
and variety of poisons found at the illegal marijuana plots is a new threat. According to co-author PSW wildlife biologist Dr. Kathryn Purcell exposure of wildlife to pesticides has been documented widely
either directly consuming flavored rodenticides or by consuming prey that had ingested recently the poisons exposure may also predispose animals to dying from other causes.
Exposure to lower doses--or to combinations--of the poisons results in slower reflexes reduced ability to heal from injuries and neurological impairment.
In this study scientists reported on the amount of poisons found at over 300 illegal plots
which may also be exposed to the poisons say the scientists. The full report can be found at http://treesearch. fs. fed. us/pubs/43761headquartered in Albany Calif. the Pacific Southwest Research Station develops
#Illegal marijuana grows threaten fishers in the southern Sierra Nevadarat poison used on illegal marijuana grows is killing fishers in the southern Sierra nevada according to a recent study conducted by a team of scientists from the U s. Forest Service's Pacific
The authors speculated that the most likely source of the poisons was the illegal marijuana grows found throughout the Sierra nevada.
The researchers deduced that illegal marijuana grows are a likely source of the poison because the fishers in this study were radio-tracked and many were observed not venturing into rural urban
and variety of poisons found at the illegal marijuana plots is a new threat. According to co-author PSW wildlife biologist Dr. Kathryn Purcell exposure of wildlife to pesticides has been documented widely
either directly consuming flavored rodenticides or by consuming prey that had ingested recently the poisons exposure may also predispose animals to dying from other causes.
Exposure to lower doses--or to combinations--of the poisons results in slower reflexes reduced ability to heal from injuries and neurological impairment.
In this study scientists reported on the amount of poisons found at over 300 illegal plots
which may also be exposed to the poisons say the scientists. The full report can be found at http://treesearch. fs. fed. us/pubs/43761headquartered in Albany Calif. the Pacific Southwest Research Station develops
when one plant restricts the growth of another by releasing toxins. They set out to determine
I.).Yield losses the use of insecticides and corn hybrids engineered to express rootworm-killing toxins in their tissues cost U s. growers at least $1 billion a year.
Lambert said that another theory is that excess fat in the diet interferes with the body's ability to keep a bacterial component called endotoxin from entering the bloodstream through gaps between cells in the digestive system--gut barrier function
Refuges consist of standard non-Bt plants that pests can eat without ingesting Bt toxins. Computer models showed that refuges should be especially good for delaying resistance
In addition to mechanical defenses such as thorns and spines plants also produce compounds that keep insects and other herbivores at bay by acting as repellents or toxins.
On the flip side outcomes were not favorable for our ancestors who ate poisonous mushrooms for example he said.
and amphibians and setting poisoned bait for rodents. The California Leafy Green Hander agreement is transparent flexible
Arsenic is classified as a poison by the National institutes of health and is considered a carcinogen by the National Toxicology Program.
and pollen and are exposed potentially to thousands of different types of phytochemicals yet they only have one-third to one-half the inventory of enzymes that break down these toxins compared to other species Berenbaum said.
and with that food so are potential toxins Berenbaum said. Her team showed that p-coumaric acid turns on not only P450 genes but representatives of every other type of detoxification gene in the genome.
In a new study at UC San francisco researchers measuring chemicals in the blood and urine concluded that hookah smoke contains a different--but still harmful--mix of toxins.
Toxins Unique to Hookah Smoking The UCSF study included eight men and five women all of whom had previous experience smoking cigarettes
The differences in the slew of toxins that ended up in the bodies of volunteers were due largely to the fact that the smokers were smoking two different materials according to Benowitz.
In general exposures for various known toxins differed for the two modes of smoking the researchers found.
but mistakenly used only one-tenth the amount of the toxin he had intended. The results were so unbelievable that he repeated the experiment.
Therefore the insects are exposed to toxins before they even sense the presence of metals. Although many metals are required by living organisms in small amounts they can be toxic to both plants
#Multi-toxin biotech crops not silver bullets, scientists warnthe popular new strategy of planting genetically engineered crops that make two
or more toxins to fend off insect pests rests on assumptions that don't always apply UA researchers have discovered.
A strategy widely used to prevent pests from quickly adapting to crop-protecting toxins may fail in some cases
Compared with typical insecticide sprays the Bt toxins produced by genetically engineered crops are much safer for people
Bt crops were grown first widely in 1996 and several pests have already become resistant to plants that produce a single Bt toxin.
each plant produces two or more toxins that kill the same pest. As reported in the study the pyramid strategy has been adopted extensively with two-toxin Bt cotton completely replacing one-toxin Bt cotton
since 2011 in the U s. Most scientists agree that two-toxin plants will be more durable than one-toxin plants.
The extent of the advantage of the pyramid strategy however rests on assumptions that are met not always the study reports.
Redundant killing can be achieved by plants producing two toxins that act in different ways to kill the same pest he said so
if an individual pest has resistance to one toxin the other toxin will kill it.
For their experiments the group collected cotton bollworm--also known as corn earworm or Helicoverpa zea-a species of moth that is a major agricultural pest and selected it for resistance against one of the Bt toxins Cry1ac.
As expected the resistant caterpillars survived after munching on cotton plants producing only that toxin. The surprise came
If the assumption of redundant killing is correct caterpillars resistant to the first toxin should survive on one-toxin plants
but not on two-toxin plants because the second toxin should kill them Carriã re explained.
But on the two-toxin plants the caterpillars selected for resistance to one toxin survived significantly better than caterpillars from a susceptible strain.
These findings show that the crucial assumption of redundant killing does not apply in this case
and may also explain the reports indicating some field populations of cotton bollworm rapidly evolved resistance to both toxins.
and Cry2 toxins occurred in 19 of 21 experiments. Contradicting the concept of redundant killing cross-resistance means that selection with one toxin increases resistance to the other toxin.
According to the study's authors even low levels of cross-resistance can reduce redundant killing
and some other pests that are not highly susceptible to Bt toxins to begin with. The team found violations of other assumptions required for optimal success of the pyramid strategy.
In particular inheritance of resistance to plants producing only Bt toxin Cry1ac was dominant which is expected to reduce the ability of refuges to delay resistance.
Refuges consist of standard plants that do not make Bt toxins and thus allow survival of susceptible pests Under ideal conditions inheritance of resistance is not dominant
According to Tabashnik overly optimistic assumptions have led the EPA to greatly reduce requirements for planting refuges to slow evolution of pest resistance to two-toxin Bt crops.
#Cancer biologists find DNA-damaging toxins in common plant-based foodsin a laboratory study pairing food chemistry
Despite those engaging in the relighting practice smoking fewer cigarettes there is no estimated reduction in their exposure to toxins says Steinberg.
#Masked mold toxins in food should be included in safety regulationsgovernment limits on mold toxins present naturally in grain crops should be expanded to include so-called masked mycotoxins that change from harmless to potentially harmful forms in the body a new
and other plants produce toxic substances termed mycotoxins. Some health experts regard mycotoxins as the most serious chronic dietary risk factor greater than the potential health threats from pesticides and insecticides.
Government regulations thus limit levels of mycotoxins that are permissible in food and animal feed.
Plants protect themselves by binding or conjugating glucose sulfur or other substances to the mycotoxin producing conjugated mycotoxins that are not harmful.
Dall'Asta explains that these masked mycotoxins are included not in current safety regulations because of uncertainty about
what happens when people and animals eat them. The new study focused on two of the most widespread mycotoxin contaminants of grain crops--deoxynivalenol (DON) and zearalenone (ZEN.
The authors say their results show for the first time that bacteria present in the large intestine in people deconjugate
For this reason masked mycotoxins should be considered when evaluating population exposure the study concludes. Story Source:
#Benefits of Bt corn go beyond rootworm resistanceengineered to produce the bacterial toxin Bt Bt corn resists attack by corn rootworm a pest that feeds on roots
or serve as a poison to herbivores. These chemicals are effective in deterring the feeding of most general insect herbivores.
A well-studied practice by some specialist insects is their predilection to consume these plant poisons sequester those poisons into parts of their body then exploit the poisons for their own protection.
#Vultures foraging far and wide face a poisonous futurea first ever study of the range and habits of white-backed vultures across southern Africa shows that they often shun national parks preferring to forage further afield on private farmland.
This behaviour and their tendency to scavenge in groups means that vultures risk encountering dead cattle that have been administered veterinary drugs that are poisonous to them
or even poisoned carcasses intended to control other carnivores such as jackals. The research using Global Positioning System (GPS) satellite transmitters to track the movements of adolescent vultures is published in the journal PLOS ONE.
which poison the fishers must also be considered when evaluating the population. We hope that we can continue to monitor the fisher
so that airborne toxins are exposed to the epithelial layer of the tissue just as it would occur in the lungs.
and can be filled with toxins--a natural defence mechanism in most trees and plants--so the monkeys are forced actually to spend more time seeking out the right foliage to eat such as new shoots
They even release toxins to make it less likely native plants will germinate near them. Why then are recent popular science articles recommending a recalibration of the traditional no-tolerance attitude toward nonnative species suggesting that we've been unfair to invasives
It has developed resistance to against more than 50 insecticides including DDT Bt toxins among others making the use of chemicals as a control measurement become ineffective.
Graphene oxide's large surface area defines its capacity to adsorb toxins Kalmykov said. So the high retention properties are not surprising to us he said.
Graphene oxide introduced to simulated wastes coagulated within minutes quickly clumping the worst toxins Kalmykov said.
and lower toxin levels the sample size and duration of treatment did not allow statistical significance.
and bacteria that damage the plant itself or bacteria like the Shiga-toxin producing E coli O104:
Grasses and crops such as maize attach sugars to chemical defenses called benzoxazinoids to protect themselves from being poisoned by their own protective agents.
Then when an insect starts feeding a plant enzyme removes the sugar to deploy the active toxin.
When the researchers examined the frass of these pests â pests that cause enormous crop damage â they found the toxin with sugar still attached.
In contrast to the original plant compound the new substance can no longer be cleaved by the plant enzyme to generate the toxin.
which explains the success of Spodoptera species. Plants usually defend themselves against insect feeding by producing toxins or deterrents.
and can feed on plant tissues containing toxins or deterrents without the expected negative effects. Insects overcome plant defenses by the rapid excretion sequestration
The elegance of such a mechanism comes from its simplicity yet it saves the insects from being poisoned said Felipe Wouters who performed the experiments for his doctoral thesis at the institute summarizing the results.
Is the methane contamination observed in drinking water a precursor to other toxins--arsenic various salts radioactive radium
Parthenium is poisonous. People who come into contact with it can suffer from skin irritations bronchial asthma and fever.
which fights off toxins that can cause DNA and cell damage. Vanessa Er from the School of Social and Community Medicine at the University of Bristol and Bristol Nutrition BRU led the research.
Kendall believes that by eating crickets infected with eyeworms quail were actually swallowing a poisoned pill.
Since nothing is burned ECIG vapor does not contain many of the toxins present in tobacco smoke.
Adding them to affected cells in other words cells treated with the environmental poison Paraquat or with a down-regulated DJ-1 decreased the toxic effect of the herbicide restored the activity of the mitochondria
and military troops exposed to poisonous chemicals--particularly those in pesticides and chemical weapons. An article in the current issue of the journal Chembiochem outlines the advancement in detoxifying organophosphates
(which hosts a fungus called epichloã festucae that produces the toxin ergovaline) results in slower fungus growth and less toxicity.
which over time has resulted in fewer toxins within their preferred area. We know that animals can remember
juniper toxins are found inside juniper needles. Most mammals are herbivores. Some face serious challenges:
Plant toxins determine which plants a herbivore can eat says Kohl. Liver enzymes help animals detoxify such poisons.
Researchers previously isolated toxin-degrading microbes from herbivores but Kohl and Dearing say that until now scientists have lacked strong evidence for
what has been conventional wisdom: Gut microbes also help some herbivores eat toxic plants. The study involved desert woodrats (Neotoma lepida)--grayish rodents native to western North american deserts.
Woodrats somehow acquired novel toxin-degrading gut microbes to adapt to climate and vegetation changes that began 17000 years ago.
Transfer of toxin-degrading microbes from one organism to the other is much more rapid Dearing says.
Mammals are adapted to the plant toxins they eat Kohl says. The guts of creosote-fed woodrats were teeming with microbes that may degrade creosote
when woodrats didn't get transplants of creosote-detoxifying microbes their urine was more acidic suggesting their livers expended a lot of energy to degrade creosote toxins.
In the study the essential oil killed several strains of Shiga toxin-producing Escherichia coli (E coli) known to the U s. Centers for Disease Control and Prevention as non-O157 STEC.
because they are deadly poisonous Bohs says. The Solanaceae family including the Genus solanum is known as the nightshade family
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