tox unit 4

Batrachotoxin:

mechanism:

what it does:

animal example:

Batrachotoxin:

mechanism:

what it does:

animal example:

mechanism: irreversibly binds to all Na channels

what it does: neuro and cardio tox, one of most POTENT toxins

animal example: poison dart frogs

Tetrodotoxin (TTX)

mechanism:

what it does:

animal example:

mechanism: block neuronal and skeletal Na channel with high affinity

what it does: diaphragm paralysis

animal example: pufferfish, pumpkin toad

Saxitoxin and Brevetoxin

mechanism:

animal example:

mechanism: blocks Na channel

animal example: red tide algae

Milkweed

mechanism:

what it does:

animal example:

mechanism: cardiac glycoside

what it does: initiates cardiac arrhythmias

animal example: butterfly

Bufotoxin- Steroidal glycoside

mechanism:

what it does:

animal example:

mechanism: inhibits Na/K/ATPase in the heart

what it does:

animal example: cane toad

Bufotoxin- Tryptamine related substance (5Me-O-DMT)

mechanism:

what it does:

animal example:

mechanism: act on seratonin receptor

what it does: increase HR

animal example: colorado river toad

what toxins do millipedes have

benzoquinones and HCN

Venom components: proteolytic enzymes

what they do:

examples:

Venom components:

what they do: break down tissue proteins

examples: collagenase for pre digestion. hyaluronidase to lower viscosity of interstitial fluid and increase tissue permeability.

Venom components: enz that interfere with coag

what they do:

examples:

Venom components:

what they do: increase thrombin activity

examples: serine protease, metalloproteinases, anticoag

Venom components: degredative enzymes

what they do:

examples:

Venom components:

what they do: duh

examples: PLA2 hydrolyzes phospholipids. Melittin in bee venom, stim PLA2.

Venom components: neuro and cardiotoxins

what they do:

examples:

Venom components:

what they do: respiratory paralysis

examples: alpha bungarotoxin and fasciculin

name the ion channel venom

scorpion:

snails:

snake:

bees:

scorpion: margatoxin and charybdtoxin

snails: conotoxin

snake: dendrotoxin

bees: apamin

what scorpion uses charbdtoxin

death stalker

what scorpion has unique cardiac involvement and uses what blocker

P. transvaalicus, t type blocker

what scorpion is most venemous

arizona bark

australian funnel web/grass spider uses what toxins

atracotoxins: Na activators

agatoxins: VDCC blockers

(only hobo spider causes necrotic lesions)

what toxin does black window use

latrotoxins- inc Ca in nerve terminals

what toxin does brown recluse use

sphingomyelinase D catalyses hydrolysis of sphingomyelin and causes hemolysis

what toxin do tarantulas use

ion channels

what venoms do killer bees use

apamin, melittin, PLA2

what jellyfish is the biggest

Lion’s Mane

what jellyfish is the most venemous + describe mechanism

box jelly

C. fleckeri toxin 2. hemolytic and disrupts ion conc

what jelly is the most frightening

Irukandji/Doom jelly

what jelly is the most useful

A. victoria. GFP

Difference between vipers and elapids?

vipers; hollow hinged fangs, found in Americas, Africa, Eurasia

elapids: hollow fixed fangs, found in tropical regions

what does Russel’s viper venom do

contains RVV, converts prothrombin to thrombin. causes coagulation

how is Russell’s viper venom a diagnostic tool

lupus creates antibodies against PL

venom converts in presence of PL

Lupus apatients will have prolonged dRVVT time due to low phospholipid levels

describe dif between black and green mambas

black: most venemous, cardiotox and neurotoxins

green: not aggressive, less potent venom

what is the most venomous land snake and what does its venom do

Australian Taipan. targets CV system.

Death Adder venom contains acanthins, which effects?

coagulation

what are most snake fatalities due to

diamondbacks

what is the only venomous snake in VT

Timber Rattlesnaeks

what are the most amount of snake bites due to

copperheads

how do you tell a coral snake?

red touch yellow, kill a fellow

describe how brazilian pit viper can be used as tool

Teprotide is isolated, decreases conv of ang1 to ang2. decreases blood pressure. ACE captopril is prototype.

how does food help alc absorp

food decreases rate of gastric emptying, slowing absorption in intestine

carbs>fat>protein

elimination rate of alc is what order

0th

Forward extrapolation uses what equation

Widmark (watson improves widmark)

what is the gold standard for determining ACUTE alcohol intox

BAC

list from fewest to most amt of time, window of detection for samples

fluid/blood hours to days

urine days to weeks

hair weeks to months

EtG is a

direct metabolite of ethanol present in hair and urine

FAEE enters hair by

diffusion

describe the steps of hair tissue collection

1. collection from back of head

2. decontamination

3. extraction

4. separation using gas chromatography then tandem MS

dif between sensitivity and selectivity

sensitivity: detect if analyte is there

selectivity: ability to NOT detect if analyte is NOT there

what assay is the standard test for good lower limit for Et

GC-MS

describe the gap period and the solution to this

day 4 and week 6 where EtG isnt detected in blood urine saliva or hair

solution is phosphatidyl ethanol (PEth) blood test

normally PLD acts on PC to produce PA

in the presence of ethanol, PLD produces PEth through transphosphatidylation

pros and cons of PEth tissue sample

Dried blood spots

adv: suitable for field

limit: have to compare to venous conc and normalize to hematocrit

what form of PEth are we assaying for

16:0/18:1

what assay is the gold standard for PEth

LC-MS

Describe direct, indirect, and the most direct indicator

direct: FAEE, EtG, PEth form ONLY in presence of Et. timing of drinking affects indicators (longer sip time= less direct indicators formed)

indirect: liver enzymes (transferases) prone to false postive

most direct: ethanol through BAC. 5% of alcohol is elim through lungs

BAC inferred based on

henrys law

describe VT using Datamaster

uses beer lambart law to measure Et

measuring absorption at multiple wavelengths of light to yield a “fingerprint” for ethanol

important to get deep breath

what is the gold standard for alc tests

blood: high sensitivity

what test detects alc in sweat

SCRAM

what do you test for in methanol cases

how does it work

what is the antidote

formic acid

inhibits cyt c oxidase

fomepizole

name the 3 types of phytocannabinoids

delta THC (psychoactive)

hydroxy THC (psychoactive)

carboxy THC (inactive)

describe urine testing for cannabis

CONFIRMATORY TEST

normalize values to creatinine

then do immunoassay
competitive: drug strips
non comp: ELISA

why is it possible for someone to be high but have no delta THC

it has been converted to hydroxy THC

describe cannabis breath test

need to use two time points to determine ½ life of delta THC and anther. promising bc had no false positives.