An electrochemical biosensor capable of detecting low levels of cancer biomarkers is reusable over 200 regeneration cycles without compromising device sensitivity and accuracy.
In the world of nanotechnology, the development of dynamic systems that respond to molecular signals is becoming increasingly important. The DNA origami technique, whereby DNA is programmed so as to produce functional nanostructures, plays a key role in these endeavors. Teams led by LMU chemist Philip Tinnefeld have now published two studies showing how DNA origami and fluorescent probes can be used to release molecular cargo in a targeted manner.
In the journal Angewandte Chemie (“DNA Origami Vesicle Sensors with Triggered Single-Molecule Cargo Transfer”), the researchers report on their development of a novel DNA-origami-based sensor that can detect lipid vesicles and deliver molecular cargo to them with precision.
The sensor works using single-molecule Fluorescence Resonance Energy Transfer (smFRET), which involves measuring the distance between two fluorescent molecules. The system consists of a DNA origami structure, out of which a single-stranded DNA protrudes, which has been labeled with fluorescent dye at its tip. If the DNA comes into contact with vesicles, its conformation changes. This alters the fluorescent signal, because the distance between the fluorescent label and a second fluorescent molecule on the origami structure changes. This method allows vesicles to be detected.
The accumulation of mutations in DNA is often mentioned as an explanation for the aging process, but it remains just one hypothesis among many. A team from the University of Geneva (UNIGE), in collaboration with the Inselspital, University Hospital of Bern and the University of Bern (UNIBE), has identified a mechanism that explains why certain organs, such as the liver, age more rapidly than others.
The mechanism reveals that damages to non-coding DNA, which are often hidden, accumulate more in slowly proliferating tissues, such as those of the liver or kidneys. Unlike in organs that regenerate frequently, these damages remain undetected for a long time and prevent cell division. These results, published in the journal Cell, open new avenues for understanding cellular aging and potentially slowing it down.
Our organs and tissues do not all age at the same rate. Aging, marked by an increase in senescent cells —cells that are unable to divide and have lost their functions—affects the liver or kidneys more rapidly than the skin or intestine.
Understanding how light travels through various materials is essential for many fields, from medical imaging to manufacturing. However, due to their structure, materials often show directional differences in how they scatter light, known as anisotropy. This complexity has traditionally made it difficult to accurately measure and model their optical properties. Recently, researchers have developed a new technique that could transform how we study these materials.
Getting tips from the design of the human body.
Scientists create bone-inspired cement, over five times stronger than concrete.
Continue reading “Human bone-inspired cement is 5 times tougher than standard concrete” »
Results from a large clinical trial show that treatment with an immunotherapy drug may nearly double the length of time people with high-risk, muscle-invasive bladder cancer are cancer-free following surgical removal of the bladder. Researchers found that postsurgical treatment with pembrolizumab (Keytruda), which is approved by the Food and Drug…
For billions of years, life has used long molecules of deoxyribonucleic acid, or DNA, to store information and solve problems.
Today engineers are putting their own spin on DNA computing, to both record data and serve as biological computers, yet until now they’ve struggled to design a synthetic system that can store and perform tasks at the same time.
New research has now demonstrated it’s possible to package and present DNA so it can manage both, providing a full suite of computing functions out of strings of nucleic acids. Specifically, we’re talking about storing, reading, erasing, moving, and rewriting data, and handling these functions in programmable and repeatable ways, similar to how a conventional computer would operate.
Mesmerizing microscopic footage showing “waves” inside a developing fly embryo has won the 14th annual Nikon Small World in Motion competition.
These “mitotic waves” occur during cell division as tissue forms and moves in the embryo of a fruit fly (Drosophila melanogaster). Understanding this biological process in flies could help reveal the forces that build embryos across the animal kingdom. Many of these fundamental processes can go awry in humans, leading to neurological disorders, congenital defects and cancer.
Back in August 2021, LA-based Portl launched a 7-ft-tall hologram projection box for life-like remote communications. Now renamed Proto, the company has revealed that its Epic technology is allowing cancer patients to consult life-size virtual specialists.
Proto was founded in 2018 by David Nussbaum, who took his experience working on huge holograms for arena gigs, movie premieres and fashion shows to produce a hologram in a box called the Epic. The idea is to plonk the machine in a venue, university, boardroom, medical facility and so on, and allow folks to chat with a life-like 3D hologram of a person who might be thousands of miles away.
Continue reading “Dr. Hologram will see you now: Virtual specialists visit cancer patients” »
However, more recent research suggests there are likely countless other possibilities for how life might emerge through potential chemical combinations. As the British chemist Lee Cronin, the American theoretical physicist Sara Walker and others have recently argued, seeking near-miraculous coincidences of chemistry can narrow our ability to find other processes meaningful to life. In fact, most chemical reactions, whether they take place on Earth or elsewhere in the Universe, are not connected to life. Chemistry alone is not enough to identify whether something is alive, which is why researchers seeking the origin of life must use other methods to make accurate judgments.
Today, ‘adaptive function’ is the primary criterion for identifying the right kinds of biotic chemistry that give rise to life, as the theoretical biologist Michael Lachmann (our colleague at the Santa Fe Institute) likes to point out. In the sciences, adaptive function refers to an organism’s capacity to biologically change, evolve or, put another way, solve problems. ‘Problem-solving’ may seem more closely related to the domains of society, culture and technology than to the domain of biology. We might think of the problem of migrating to new islands, which was solved when humans learned to navigate ocean currents, or the problem of plotting trajectories, which our species solved by learning to calculate angles, or even the problem of shelter, which we solved by building homes. But genetic evolution also involves problem-solving. Insect wings solve the ‘problem’ of flight. Optical lenses that focus light solve the ‘problem’ of vision. And the kidneys solve the ‘problem’ of filtering blood. This kind of biological problem-solving – an outcome of natural selection and genetic drift – is conventionally called ‘adaptation’. Though it is crucial to the evolution of life, new research suggests it may also be crucial to the origins of life.
This problem-solving perspective is radically altering our knowledge of the Universe. Life is starting to look a lot less like an outcome of chemistry and physics, and more like a computational process.
In the world of nanotechnology, the development of dynamic systems that respond to molecular signals is becoming increasingly important. The DNA origami technique, whereby DNA is programmed so as to produce functional nanostructures, plays a key role in these endeavors. Teams led by LMU chemist Philip Tinnefeld have now published two studies showing how DNA origami and fluorescent probes can be used to release molecular cargo in a targeted manner.
