Toxicology Final (copy)

what would you give for immediate treatment of snake bite pt?

NSAIDs + analgesia

alpha-bungarotoxin (banded krait)

nicotinic acetylcholine receptor antagonist

tetrodotoxin (puffer fish)

Na+ channel blocker

dendrotoxin (black mamba)

K+ channel blocker

W-conotoxin (coneshell snail)

Ca2+ channel blocker

list the 3 primary metabolic disorders associated w/ cell necrosis in response to toxicants

- ATP depletion

- sustained rise in intracellular Ca2+

- overproduction of ROS/RNS

Give an example of a toxicant that depletes ATP by impairment of the electron chain for ATP production

- cyanide

- rotenone

- paraquat

primary changes in ATP levels can result in secondary increases in intracellular Ca2+ levels, but primary changes in intracellular Ca2+ have no interaction w/ producing changes in ATP levels

False

what are the key characteristics of the target molecule in the model for mechanisms of toxicity?

- accessibility

- critical function

what characteristic of proteins makes them targets for many toxins?

their 3-D shape (tertiary structure) which determines function

what are the 2 major classes of genes that can be involved in carcinogenesis according to the current models?

- proto-oncogenes

- tumor suppressor genes

at what points in the carcinogenesis model can non-genotoxic carcinogens exert and effect?

- DNA replication

- clonal expansion

what is the toxic agent associated w/ corn lily (Veratrum californicum)?

cyclopamine

what are the 4 general types of neurotoxicity?

- neuropathies

- axonpathies

- myelinopathies

- functional (neurotransmission-associated)

A client calls your emergency clinic at 1P because he came home from church services on Easter Sunday to find his chocolate lab (MN, 75 lbs) had developed a taste for chocolate and eaten most of a bag full of Hershey kisses and chocolate bunnies. What should be your first response?

Ask the client if the dog is showing any clinical signs

Which toxicant produces the condition known as "shake and bake" in dogs in reference to the clinical signs of hyperthermia and seizures?

metaldehyde

Why does lead have a long biological half life in animals?

Lead has a similar valence to Calcium and binds to high Calcium compartments like bone

What is the mechanism by which excess blood ammonia causes toxicity?

NH3 in mitochondria forms reactive oxygen species

Salt toxicity has 2 mechanisms for its occurrence, direct salt toxicity is due to ________

dehydration (reduced water intake)

Salt toxicity has 2 mechanisms for its occurrence, indirect salt toxicity is due to ________

excess salt in diet

what sources can contain botulism as a source?

- water contaminated by decaying fish

- improperly stored grains

- improperly stored home canned foods

what attributes of toxicity are similar between botulism and tetanus?

- both are produced by spore forming rods of the bacterium, Clostridium

- both act at vesicle proteins to prevent neurotransmitter release

locoweed (oxytropis)

swainsonine (inhibits mannidosase enzymes)

swainsonine of locoweed (oxytropis)

inhibits mannidosase enzymes

larkspur (Delphinium)

diterpene alkaloid (methyl-lycanotine -nicotinic receptor antagonist)

diterpene alkaloid of larkspur (Delphinium)

methyl-lycanotine -nicotinic receptor antagonist

monkshood (aconitum)

diterpene alkaloid aconitine (sodium channel blocker)

diterpene alkaloid aconitine of monkshood (aconitum)

sodium channel blocker

mum (Chrysanthamum)

pyrethrin (sodium channel blocker)

pyrethrin of mum (Chrysanthamum)

sodium channel blocker

Cyanobacteria (anabaena, microcystis)

anatoxin (acetylcholinestease inhibitor)

anatoxin of Cyanobacteria (anabaena, microcystis)

acetylcholinesterase inhibitor

If you apply a low dose atropine test to a dog with suspected organophosphate poisoning and the signs of salivation, miosis, urination, and bradycardio persist, what would be the next course of action?

apply a high dose of atropine as treatment for organophosphate toxicity

An 8 yr old Bernese mix breed (FS, 55 lbs) has gone missing from her owner for ~24 hrs. When she returned home, her fur was matted and filled with plant matter and other materials. Shortly after she got home, she started showing signs of weakness, ataxia, and lethargy. She has been brought to your clinic. Initial examination finds nothing of marked change other than the presenting clinical signs. While you are waiting for her to stabilize you have the techs give her a good bath and grooming before she is placed in a recovery cage. Several hours later she is bright and alert with minimal signs of weakness or ataxia. After an overnite stay, she presents as reatlvely healthy and normal. What is your suspected diagnosis?

possible tick paralysis that resolved with the bath and removal of the ticks, although none were reported by the techs

What is the mechanism of action of methylxanthines?

inhibit phosphodiesterase and increase cAMP

Which toxicant is an inhibitor of the neurotransmitter glycine and produces muscle tetany and death?

strychnine

which plants are known to carry cardiac glycosides among their chemical toxicants?

- milkweed

- foxglove

- lilly of the valley

toxicity associated w/ _____ is characterized by clinical signs of respiratory distress and chocolate brown blood.

nitrite

toxicity associated w/ nitrites is characterized by clinical signs of respiratory distress and chocolate brown blood. a common source of this toxicant in horses is ____

red maple

which plants are known to carry hyoscyamine and scopolamine among their chemical toxicants?

- Jimsonweed

- deadly nightshade

toxicity associated w/ _______ is characterized by clinical signs of respiratory distress and cherry red blood.

cyanide

toxicity associated w/ cyanide is characterized by clinical signs of respiratory distress and cherry red blood. this toxicant is typically ingested as a precursor compound called ____ that is metabolized to form the toxicant

amygdalin OR prunsain (prussic acid)

which plant has a toxicant that inhibits GABA receptors and therefore has clinical signs similar to strychnine?

water hemlock (Cicuta spp)

the treatment for cyanide toxicity is to administer

sodium nitrite

the treatment for cyanide toxicity is to administer sodium nitrite to create the condition of _____ that binds the cyanide

methemoglobinemia

which gasses are of concern in areas of manure pits?

- methane

- hydrogen sulfide

what is the mechanism of ionphore toxicity?

ECG disturbance and arrhythmia

in the hepatic acinus model, which zone has the lowest oxygen tension and is where most xenobiotic metabolism occurs?

zone 3 (centrilobular)

pyrrolizidine alkaloids are found in 2 major genuses of plants

- senecio

- crotalaria

pyrrolizidine alkaloids are found in 2 major genuses of plants, Senecio and Crotalaria. these are toxicants of which organ?

liver

what is the most common type of mycotoxin, produced by Aspergillus, that can be found as a low level contaminant of grains and processed pet foods?

alfatoxin

Fescue toxicity is associated with the compound

ergovaline

Fescue toxicity is associated with the compound ergovaline that is produced by a(n) _____ known as Neotyphodium

endophyte

what is a unique clinical feature of death cap mushrooms (Amanita spp) that you must be aware of if treating suspected mushroom ingestion in a dog?

initial clinical signs of GI distress will resolve, but organ failure may occur 1-3 days later

what is the reason for the presence of Heinz bodies in toxicity associated w/ Allium plants?

sulfur binding hemoglobin

what is the source of ergopeptides in ergot poisoning?

grain infected w/ claviceps purpurea

Which neuroreceptors can ergopeptides from Claviceps act agonistically in an animal’s body?

Epinephrine alpha adrenergic receptor
Serotonergic receptor

Dopamingergic receptor

what plant is a source of molecules such as dicoumarol from which warfarin is derived?

sweet clover

the rodenticide cholecalfiferol is also known as ____

vitamin D

the rodenticide cholecalciferol is also known as vitamin D and its toxicity produces a condition known as

(dystrophic) mineralization

which toxic plant contains the compounds ptaquiloside and thiaminase?

bracken fern

The toxicant responsible for the condition known as slobbers is produced by _______ during period of drought stress on pastures

Rhizoctonia leguminicola fungus

The toxicant responsible for the condition known as slobbers produced by red clover fungus during period of drought stress on pastures

Slaframine

which popular house plant can produce renal toxicity in cats as a result of ingestion the pollen?

Easter lily (lilium spp.)

Post mortem finding of peri-renal edema and degeneration of proximal and distal tubules would be considered diagnostic for which toxicant source

Redroot pigweed (Amaranthus)

Ingestion of oxalate containing plants, if in sufficient quantity to have oxalates exposed systemically, can produce toxicosis similar to that of _______ glycol antifreeze

ethylene

There are two possible therapies for ethylene glycol toxicity, one is

- _____ which is low cost but has side effects

ethanol (alcohol)

There are two possible therapies for ethylene glycol toxicity, one is

- _____ which is expensive but very effective

fomepizole

A dog presenting to your emergency clinic for acute onset of vomiting, ataxia, general depression and seizures may be suffering from a number of possible toxicities or organic diseases. Once you get a blood chemistry back and you find hypoglycemia and hypokalemia, what would be your suspected diagnosis?

xylitol

Based on nomenclature and presumably clinical data, which NSAIDs would be the most cycloxygenase 2 selective?

- deracoxib

- robenacoxib

-firocoxib

Where are you most likely to see photosensitive dermatitis localized?

dorsum w/ light colored skin/fur

in secondary photosensitization, what is the typical source for the sensitizer molecule?

chlorophyll metabolites not filtered by the liver due to hepatotoxicity

Sheep presenting with sloughing hooves, fur/ wool loss, and blind staggers most likely have _____ toxicity

selenium

Sheep presenting with sloughing hooves and blind staggers most likely have selenium toxicity associated with what source

- locoweeds

- milk vetches

(Astragalus genus)

Genestein is considered one of the parent glycosides for what class of toxicants?

phytoestrogens

The parent glycosides for most clinically relevant isoflavones in clover are genestein ,______, and _____

formononetin
biochanin A

Clovers contain phytoestrogens classified as 

isoflavones

The occurence of pre-pubertal vulva swelling and mammary development in gilts is commonly associated with the mycotoxin

zearalenone

The occurence of pre-pubertal vulva swelling and mammary development in gilts is commonly associated with the mycotoxin zearalenone which is produced by the fungus

Fusarium

Which low growing plant with yellow flowers that bloom in May-June produce a potent irritant to mucous membranes and may induce colic in horses?

buttercup (ranunculus)

Which plant contains the most potent chemical toxin known, yet has a number of commercial uses as well?

castor bean (ricinus)

Which toxicant that has multiple organ toxicities (renal, hepatic, cardiac) is also associated with the disruption of normal spermatogenesis?

gossypol

Which class of antibiotics is associated with chondrocyte impairment in fast-growing, large breed dogs?

flouroquinolones

Which plants, discussed in lecture, are associated with primary photosensitization by the route of ingestion?

Buckwheat (Fagopyrum)
St. John’s Wort (Hypericum)

Where would the more common spot(s) be on an animal where they might receive a venomous snake bite?

- nose/muzzle

- lower limbs

2 primary venomous arachnids present in the US

- brown recluse

- black widow

Of the multiple steps in treatement of a toxicity, what is the first and most important step?

stabilization

In any case of an ingested poison that is taken to an emergency clinic within the first hour of ingestion, it is always appropriate to induce emesis.

False

What compound is commonly used to decontaminate the gastrointestinal tract following an ingested poison.

activated charcoal

Of the multiple steps in treatment of a toxicity, what is unique to cases of poison exposure?

Decontamination

genus of copperhead

agkistrodon

genus of water moccasin

agkistrodon

genus of eastern diamondback rattlesnake

crotalus

genus of pygmy rattlesnake

sistrurus

genus of coral snake

micrurus

genus of timber rattlesnake

Crotalus

The highest risk to your patient if you induce emesis will be

Aspiration

what would be contraindications to inducing emesis in response to an ingested toxin

- do not induce emesis in a patient that has vomited multiple times

- do not induced emesis if the patient is seizuring

What is the latest dopamine agonist that has been released to the market as an emetic for dogs?

ropinirole

What would be a possible method of decontamination in large animals when heavy metal toxicity is suspected?

chelator