Tag Archives: cobra

Heparin found to be effective antidote for cobra bites, say scientists

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Snake bites affect approximately 1.8 million people annually. The current standard of care is antibody-based antivenom, but it can be difficult to obtain and is generally ineffective against local tissue damage. New research suggests that heparin, a commonly used blood-clotting inhibitor, could be repurposed as an inexpensive antidote for cobra venom.

Zebra snake (Naja Nigrichinta) in Namibia. Image credit: Wolfgang Wüster.

“Our findings have the potential to significantly reduce the horrific necrotic injury caused by cobra bites, and may also slow the release of venom and improve survival rates,” Professor Greg Neely, from the University of Sydney, said.

The authors identified a way to block cobra venom using CRISPR gene editing technology and showed that heparin and related drugs could be repurposed to prevent necrosis caused by cobra bites.

“Heparin is cheap, ubiquitous and listed as an essential medicine by the World Health Organisation,” says Tian Du, a PhD student at the University of Sydney.

“If the human trials are successful, it could be used relatively quickly as a cheap, safe and effective drug to treat cobra bites.”

Using CRISPR, researchers have discovered the human gene required for cobra venom to kill flesh at the bite site.

One of the desired venom targets is an enzyme needed to make heparan and heparin, related molecules produced by many human and animal cells.

Heparan is present on cell surfaces and heparin is released during immune responses, and because of their similar structure, toxins can bind to either.

Scientists have used this knowledge to create an antidote that can stop necrosis in human cells and mice.

Unlike current cobra bite antivenoms, which are 19th century technology, heparinoids act as a “decoy” antidote.

The antidote works by injecting large amounts of “decoy” heparin sulfate or related heparinoid molecules into the bite site, which are able to bind to and neutralize the toxins in the venom that cause tissue damage.

“Our findings are intriguing because current antivenoms are largely ineffective at treating severe, localised poisoning which causes painful, progressive swelling, blistering and tissue necrosis around the bite,” said Professor Nicholas Casewell, from the Liverpool School of Tropical Medicine.

of study Published in the journal Science Translational Medicine.

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Tian Y. Du others2024. Molecular dissection of cobra venom highlights heparinoids as potential antidotes to spitting cobra venom. Science Translational Medicine 16 (756); doi: 10.1126/scitranslmed.adk4802

Source: www.sci.news

Leach Mimics Cobra with Coiling and Jumping Display

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For the first time, scientists have captured on video a leech leaping from a leaf, settling a long-standing debate about the creature’s jumping abilities.

The question of whether leeches can jump has been debated since the late 1800s when rumors of their ability first surfaced. Despite occasional sightings, conclusive evidence was lacking until now.

My Fafmi A researcher from Fordham University in New York documented this ability during fieldwork in Madagascar in 2017. While hiking, she discovered a Chtonobdella hill (Kutnobdera Falux) – A worm-sized animal that lives only in Madagascar.

“I crouched on the ground next to the leech, took out my phone and started recording,” Fahmi said. “At the time I had no idea what I was recording.” When he showed the video to his colleagues in New York, Fahmi said they all had the same reaction: “Did that leech just jump?”

Six years later, Fahmi returned to Madagascar again to attempt to record another jumping leech, and again met with immediate success: this time, he recorded two leeches interacting, one of which leapt off a leaf.

The leech prepares itself by anchoring its rear suckers to the ground (in this case a leaf) and wrapping the rest of its body around its back, then, like a cobra attacking, thrusts its body forward in one swift motion, detaching its rear suckers and launching itself into the air.

The sudden, explosive movements may be a tactic to land on or near unsuspecting prey. Although the leap is a bit awkward, “this is clearly active propulsion,” he said. Michael Tesler At Medgar Evers College in New York.

Terrestrial leeches have not been studied extensively, even though analyzing their blood meals can help conservationists track elusive animals. But finding the ability in two different individuals and locations “suggests that the behavior is more common than we thought,” Tesler says. Based on this evidence and anecdotes from other regions, he believes this is not the only jumping leech in the world.

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Source: www.newscientist.com