Wednesday, February 24, 2016

How Venoms Kill Depends Upon What Venomous Animal Is Injecting


Summary: How venoms kill depends upon the venomous animals doing the injecting since venoms make life difficult or impossible by deadly bites, spines or stings.


Two specimens of the world’s deadliest animal species, box jellyfish, are held by Jamie Seymour, James Cook University researcher and associate professor for the Queensland Tropical Health Alliance at Cairns Campus’s School of Public Health and Tropical Medicine: The Nature of Science @thenatureofscience via Instagram post of Nov. 13, 2015

Not all venoms act the same, according to the YouTube video “How Venoms Kill – Venom 101” posted Feb. 14, 2016, from the same-named entry Feb. 16, 2016, at The Nature of Science blog.
Toxins become classified as poisons when they can be eaten or ingested and as venoms when they can be injected through a bite, spine or sting. Jamie Seymour, professor and toxinologist at James Cook University in Cairns, Far North Queensland, Australia, covers three scenarios for death by venom through four venomous encounters. He describes what happens when jellyfish, snakes and stonefish turn interactions with beach-walking, grass-playing, water-loving adults and children into trauma at best and death at worst. He explains one scary sensory reaction and three scary physical changes that one snake’s fangs, one stonefish’s spines and two jellyfishes’ stings produce in their prey.
Venoms function to “destroy living cells. They can cause intense pain. They can be fast-acting. They can make blood clot” in the bodies of envenomed prey.
Professor Seymour gives examples of how venoms kill when Indian Ocean, Pacific Ocean and Tampa Bay stonefish (Synanceia spp) spines inject sticky venom into human feet. He has microscope images that show some thin, 2- to 3-millimeter- (0.08- to 0.12-inch-) long human heart cells “scrunching right up into” 0.01-inch (0.25-millimeter) “tiny balls.” Cells “squidging up” indicate that “stonefish venom is different from a lot of the other venoms in what they’re actually doing is attacking the membrane cells.”
Amputated limbs join dying cells if “big weeping ulcers” and “big holes in the bottom” of feet develop from the venom not being cleaned out timely.
Irukandji jellyfish of Australia and Philippines keep their prey in excruciating pain since “Your body tenses up. Your muscles tense up. You vomit. You throw up.” Whether of the genus Carukia or Malo, their venom possibly leads to an adrenalin production that holds raised levels far longer than 5 to 15 seconds.
Professor Seymour makes the box jellyfish (Chironex fleckeri) of Australia, New Guinea, Philippines and Vietnam examples of how venoms kill by stopping “your heart from beating.” Box jellyfish venom needs just seconds to open calcium ion channels, to prevent the heart from relaxing and to stop blood from pumping to the body.
The experiment offers a “neurologically dead” toad whose heart pumps at 60 or 70 beats a minute until turned “completely white and completely rigid” by venom.
The unconscious toad’s death by venom prompts Professor Seymour’s observation “So it’s absolutely no wonder why boxfish jellyfish are the most venomous animals on the planet.”
Brown snakes (Pseudonaja textilis) of Australia, Indonesia and Papua New Guinea qualify as similarly scary examples of how venom kills by making blood clot in prey. A blood sample taken from Professor Seymour reacts scarily to injected venom from the brown snake, second most venomous serpent after the inland taipan (Oxyuranus microlepidotus).
One reaction summarizes all: “Can you imagine that clot running through your body and getting stuck in something like your lungs, your heart or your brain?”
Cinematographer Jarrod Boord, writer Sheree Marris and Professor Seymour turn out videos on their Nature of Science blog “to showcase science and nature like never before.”

World's second most venomous snake, eastern, or common, brown snake (Pseudonaja textilis), emerges from hole and waits before re-chasing a mouse; Dunns Swamp, Wollemi National Park, New South Wales, southeastern Australia, Jan. 6, 2009: John Tann from Sydney, Australia, CC BY 2.0, via Wikimedia Commons

Acknowledgment
My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:
Jamie Seymour with box jellyfish: The Nature of Science @thenatureofscience via Instagram post of Nov. 13, 2015, @ https://www.instagram.com/p/-BKv7tGitq/?taken-by=thenatureofscience
World's second most venomous snake, eastern, or common, brown snake (Pseudonaja textilis), emerges from hole and waits before re-chasing a mouse; Dunns Swamp, Wollemi National Park, New South Wales, southeastern Australia, Jan. 6, 2009: John Tann from Sydney, Australia, CC BY 2.0, via Wikimedia Commons @ https://commons.wikimedia.org/wiki/File:Who%27s_looking_at_who%3F_(3211351150).jpg
For further information:
The Nature of Science.
Available @ http://www.thenatureofscience.com.au
The Nature of Science. 14 February 2016. “How Venom Kills – Venom 101.” YouTube.
Available @ https://www.youtube.com/watch?v=sf5fPb0YRhg
Philippe Cousteau @pcousteau. 24 February 2016. "Fascinating clip about venom from my old friend Jamie Seymour, terrific scientist and communicator and great guy." Twitter.
Available @ https://twitter.com/pcousteau/status/702555472524677120


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