Could Sound Replace Pacemakers and Insulin Pumps?

Imagine a future in which crippling epileptic seizures, faltering hearts and diabetes could all be treated not with scalpels, stitches and syringes, but with sound. Though it may seem the stuff of science fiction, a new study shows that this has solid real-world potential.

Sonogenetics – the use of ultrasound to non-invasively manipulate neurons and other cells – is a nascent field of study that remains obscure amongst non-specialists, but if it proves successful it could herald a new era in medicine.

In the new study published in Nature Communications, researchers from the Salk Institute for Biological Studies in California, US, describe a significant leap forward for the field, documenting their success in engineering mammalian cells to be activated using ultrasound. The team say their method, which they used to activate human cells in a dish and brain cells inside living mice, paves the way toward non-invasive versions of deep brain stimulation, pacemakers and insulin pumps.

Going wireless is the future for just about everything,” says senior author Dr Sreekanth Chalasani, an associate professor in Salk’s Molecular Neurobiology Laboratory. “We already know that ultrasound is safe, and that it can go through bone, muscle and other tissues, making it the ultimate tool for manipulating cells deep in the body.

Chalasani is the mastermind who first established the field of sonogenetics a decade ago. He discovered that ultrasound sound waves beyond the range of human hearing — can be harnessed to control cells. Since sound is a form of mechanical energy, he surmised that if brain cells could be made mechanically sensitive, then they could be modified with ultrasound.

In 2015 his research group provided the first successful demonstration of the theory, adding a protein to cells of a roundworm, Caenorhabditis elegans, that made them sensitive to low-frequency ultrasound and thus enabled them to be activated at the behest of researchers.

Chalasani and his colleagues set out to search for a new protein that would work in mammals. Although a few proteins were already known to be ultrasound sensitive, no existing candidates were sensitive at the clinically safe frequency of 7MHz – so this was where the team set their sights. To test whether TRPA1 protein could activate cell types of clinical interest in response to ultrasound, the team used a gene therapy approach to add the genes for human TRPA1 to a specific group of neurons in the brains of living mice. When they then administered ultrasound to the mice, only the neurons with the TRPA1 genes were activated.

Clinicians treating conditions including Parkinson’s disease and epilepsy currently use deep brain stimulation, which involves surgically implanting electrodes in the brain, to activate certain subsets of neurons. Chalasani says that sonogenetics could one day replace this approach—the next step would be developing a gene therapy delivery method that can cross the blood-brain barrier, something that is already being studied. Perhaps sooner, he says, sonogenetics could be used to activate cells in the heart, as a kind of pacemaker that requires no implantation.

Source: https://www.salk.edu/
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https://cosmosmagazine.com/

Synthetic Tooth Enamel is Stronger than Actual Human Teeth

An international team of researchers developed the synthetic enamel to outperform the real thing, according to a paper of their findings published in the journal Science. If all goes well, the findings could finally provide a compelling solution to decaying teeth.

To develop it, the team needed to replicate the interconnected nanowires of calcium in natural teeth, according to a press release from the American Association for the Advancement of Science. They were able to create a nanocomposite system that effectively imitated the toughness of actual enamel while maintaining its viscoelasticity.

They then tested the material by coating it to different shaped objects including human teeth. The team found it “exhibited high stiffness, hardness, strength, viscoelasticity, and toughness, exceeding the properties of enamel and previously manufactured bulk enamel-inspired materials,” according to the study.

It’s still a ways away from becoming commercially viable yet, but the team now plans to test the synthetic enamel to ensure it can, you know, survive in our disgusting mouths for an extended period of time. If things go well, the material could even be used on things other than teeth, such as pacemakers or damaged bones.

It’s undoubtedly an interesting and exciting bit of news considering that replicating enamel has been a longtime goal of dental researchers. Let’s just hope it can come out soon so those of us with sensitive teeth can finally stop suffering every time we eat an ice cream cone.

https://futurism.com/

How to Generate Electric Currents Within The Human Body

A new nanotechnology development by an international research team led by Tel Aviv University researchers will make it possible to generate electric currents and voltage within the human body through the activation of various organs (mechanical force). The researchers explain that the development involves a new and very strong biological material, similar to collagen, which is non-toxic and causes no harm to the body’s tissues. The researchers believe that this new nanotechnology has many potential applications in medicine, including harvesting clean energy to operate devices implanted in the body (such as pacemakers) through the body’s natural movements, eliminating the need for batteries.

The study was led by Prof. Ehud Gazit of the Shmunis School of Biomedicine and Cancer Research at the Wise Faculty of Life Sciences, the Department of Materials Science and Engineering at the Fleischman Faculty of Engineering and the Center for Nanoscience and Nanotechnology, along with his lab team, Dr. Santu Bera and Dr. Wei Ji.

Also taking part in the study were researchers from the Weizmann Institute and a number of research institutes in Ireland, China and Australia

Prof. Gazit, who is also Founding Director of the Blavatnik Center for Drug Discovery, explains: “Collagen is the most prevalent protein in the , constituting about 30% of all of the proteins in our body. It is a with a helical structure and a variety of important physical properties, such as mechanical strength and flexibility, which are useful in many applications. However, because the collagen molecule itself is large and complex, researchers have long been looking for a minimalistic, short and simple molecule that is based on collagen and exhibits similar properties. About a year and a half ago, in the journal Nature Materials, our group published a study in which we used nanotechnological means to engineer a new biological material that meets these requirements. It is a tripeptide—a very short molecule called Hyp-Phe-Phe consisting of only three amino acids—capable of a simple process of self-assembly of forming a collagen-like helical structure that is flexible and boasts a strength similar to that of the metal titanium. In the present study, we sought to examine whether the new material we developed bears another feature that characterizes collagen—piezoelectricity. Piezoelectricity is the ability of a material to generate electric currents and voltage as a result of the application of mechanical force, or vice versa, to create a mechanical force as the result of exposure to an electric field.”

In the study, the researchers created nanometric structures of the engineered material, and with the help of advanced nanotechnology tools, applied mechanical pressure on them. The experiment revealed that the material does indeed produce electric currents and voltage as a result of the pressure. Moreover, tiny structures of only hundreds of nanometers demonstrated one of the highest levels of piezoelectric ability ever discovered, comparable or superior to that of the piezoelectric materials commonly found in today’s market (most of which contain lead and are therefore not suitable for medical applications).

According to the researchers, the discovery of piezoelectricity of this magnitude in a nanometric material is of great significance, as it demonstrates the ability of the engineered material to serve as a kind of tiny motor for very small devices. Next, the researchers plan to apply crystallography and computational quantum mechanical methods (density functional theory) in order to gain an in-depth understanding of the material’s piezoelectric behavior and thereby enable the accurate engineering of crystals for the building of biomedical devices.

Prof. Gazit adds: “Most of the piezoelectric materials that we know of today are toxic lead-based materials, or polymers, meaning they are not environmentally and human body-friendly. Our new material, however, is completely biological, and therefore suitable for uses within the body. For example, a device made from this material may replace a battery that supplies energy to implants like pacemakers, though it should be replaced from time to time. Body movements—like heartbeats, jaw movements, bowel movements, or any other movement that occurs in the body on a regular basis—will charge the device with electricity, which will continuously activate the implant.”

The research was published in the prestigious journal Nature Communications.

Source: https://phys.org/