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New Glue Could Fix that Wounded Heart!

Ever watched the TV show Star Trek, where Captain Jean-Luc Picard is stabbed in the heart but yet survives due to a device that stitches wounds in the heart? Now, researchers have found an adhesive of similar function where rather than using stitches or staples, this glue repairs heart wounds which are as strong as the alternatives while avoiding complicated procedures.

A new glue could be used to seal tears in heart tissue or blood vessels.

Inventors, Jeffrey M. Karp, an associate professor of medicine at Harvard Medical School, andDr. Pedro del Nido, a cardiac surgeon at Boston Children’s Hospital explains how staples and stitches can cause problems. Each pass of a suture (stich) needle, the tissue needs to be realigned and staples can damage the tissue and moreover, it requires the process of removal. In order to solve these problems, the researchers aimed to design a water-repellent glue that could harden quickly and create a seal that could withstand the stress in a beating heart.

The liquid glue is applied either on a patch and then placed on to the hole in the tissue (shown below) or directly to the tear of the blood vessel or the intestinal wall until the glue is hardened.

The glue is used with a patch to repair a wound in the heart tissue.

The surgeon then shines ultraviolet light onto the glue which results in a rubbery substance that merges with the heart’s collagen due to the glue molecules binding with the collagen fibres creating strong chains.

This adhesive has been tested on rats and pigs and have successfully shown that it helps seal the wound quicker than other adhesives that exist. In addition, “some of those adhesives require that the tissue be dried for the adhesive to stick, while others aren’t compatible with certain types of tissue,” Karp says.

Human trials are still necessary in order for use in the clinic but the researchers are optimistic that they will be able to utilize this in Europe by the end of 2015.

– Yuri Tomura

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Catch-and-Release rather than Catch-and-Kill!

The research team angles Tiger Shark up to the boat to begin samples.

It is obvious that any kind of living animal would respond to stress through catch-and-release fishing. Scientists at the University of Miami (UM) Abess Center for Ecosystem Science and Policy and the Rosenstiel School of Marine and Atmospheric Science investigated how several species of coastal sharks respond to these stresses as a result.

The five shark species being experimented on through catch-and-release fishing were the hammerhead, blacktip, bull, lemon and tiger sharks. This was taken place in South Florida and Bahamian waters. Researchers took blood samples to examine stress, including pH, carbon dioxide and lactate levels, conducted reflex tests, as well as used satellite tags to look at their post-release survival.

The blood lactate levels of sharks were hugely affected due to them resisting to be caught, which is similar to what happens to humans during intense or exhaustive physical exercise. This is linked to mortality in many species of fish. The study showed that the hammerhead exhibited the highest levels of lactic acid build out of all five species, followed by the blacktip, bull, lemon and tiger sharks. The study even showed that after release, hammerheads were prone to delayed mortality. Hence, the hammerhead sharks are more sensitive than the other sharks whereas tiger sharks can withstand or recover from even the minimal catch and release fishing a lot better.

This study not only shows the different effects on catch-and-release fishing on the different types of sharks but also conveys that it is not guaranteed that all of these species would survive from the encounter even if it swims away from the area. This has serious conservation implications because those fragile species might need to be managed separately, especially if we are striving for sustainability in catch and release fishing.

Many of the shark populations worldwide are declining due to overfishing. In order to conserve this population, the process of catch and killing is now slowly being switched to catch and releasing. Therefore this study helps fisherman make informed decisions on which sharks make good candidates for catch and release fishing, and which do not, such as the hammerheads.

 

Yuri Tomura

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