Latest news with #WeiGao
The Star
23-05-2025
- Health
- The Star
3D printing directly inside the human body
The idea is to be able to print complex, functional structures inside the body, such as medical devices or repair cells, which can be used for regeneration treatments or to replace damaged tissue. — AFP Relaxnews For the first time, researchers in the US have succeeded in printing solid hydrogel structures directly inside the human body. This revolutionary new technique paves the way for new applications in medicine, such as the creation of artificial tissue or organs, or the treatment of diseases or injuries, directly inside the body. This feat was achieved by a team of researchers led by Professor Wei Gao of the California Institute of Technology (Caltech). It is a fascinating advance in 3D printing, applied to biological processes through the use of sound waves. The method, called deep tissue in vivo sound printing (DISP), uses liposomes, tiny vesicles composed of lipids and containing an active substance. In this case, low-temperature-sensitive liposomes loaded with cross-linking agents are injected into the body with a prepolymer solution. The application of ultrasound results in local heating of the targeted area by around five degrees Celsius, causing the liposomes to release their contents, initiating the printing of the polymer structure in a precise location. In theory, this technique makes it possible to create customised solid hydrogel structures inside the body. The idea is to be able to print complex, functional structures inside the body, such as medical devices or repair cells, which can be used for regeneration treatments or to replace damaged tissue. Ultimately, the technique could be used for biological monitoring of internal vital signs, and even help in the treatment of cancer. The next, even more ambitious step will be to use artificial intelligence to improve the precision of printing in moving organs, such as a beating heart. The research is published in the Science journal. – AFP Relaxnews
Yahoo
18-05-2025
- Health
- Yahoo
Scientists '3D Print' Material Deep Inside The Body Using Ultrasound
Scientists in the US have created a way to 3D print materials inside the body using ultrasound. Tests in mice and rabbits suggest the technique could deliver cancer drugs directly to organs and repair injured tissue. Dubbed deep tissue in vivo sound printing (DISP), the method involves injecting a specialized bioink. Ingredients can vary depending on their intended function in the body, but the non-negotiables are polymer chains and crosslinking agents to assemble them into a hydrogel structure. To keep the hydrogel from forming instantly, the crosslinking agents are locked inside lipid-based particles called liposomes, with outer shells designed to leak when heated to 41.7 °C (107.1 °F) – a few degrees above body temperature. The team, led by scientists from the California Institute of Technology (Caltech), used a beam of focused ultrasound to heat and create holes in the liposomes, releasing the crosslinking agents, and forming a hydrogel right there in the body. While previous studies have used infrared light to 3D print hydrogels in the body, ultrasound was chosen as the trigger mechanism this time because it can activate bioinks injected deeper, down to muscles and organs. "Infrared penetration is very limited. It only reaches right below the skin," says Wei Gao, a biomedical engineer at Caltech. "Our new technique reaches the deep tissue and can print a variety of materials for a broad range of applications, all while maintaining excellent biocompatibility." By precisely controlling the ultrasound beam, the team was able to 3D print complex shapes, like stars and teardrops. DISP isn't just a fun new body mod tool, though – animal tests using different versions of the hydrogel showed it could help replace or repair damaged tissue, deliver drugs, or monitor electrical signals for tests like electrocardiography. The researchers used tiny gas vesicles as an imaging contrast agent, allowing them to see when the system was working. These vesicles change their contrast when exposed to chemical reactions from the polymer crosslinking. Ultrasound picks these signals up and confirms that the reaction has worked. In rabbits, the researchers printed pieces of artificial tissue at depths of up to 4 centimeters (about 1.6 inches) below the skin. This could help speed up healing of wounds and injuries – especially if cells are incorporated into the bioink first. In tests on 3D cell cultures of bladder cancer, the team administered a version of the bioink loaded with the chemotherapy drug doxorubicin. Using the DISP method to harden it into hydrogel, the drug was released slowly over a few days. That led to significantly more cancer cell death than regular injection of the drug. Adding other ingredients to the bioink can give DISP even more uses. The researchers also made conductive bioinks using carbon nanotubes and silver nanowires, which could be used for implantable sensors for temperature or electrical signals from the heart or muscles. Importantly, no toxicity from the hydrogel was detected, and leftover liquid bioink is naturally flushed from the body within seven days, the team says. Of course, the researchers still need to cross the chasm between tests in animals and tests in humans, but 3D printing biomedical devices right there in the body is an intriguing idea. "Our next stage is to try to print in a larger animal model, and hopefully, in the near future, we can evaluate this in humans," says Gao. "In the future, with the help of AI, we would like to be able to autonomously trigger high-precision printing within a moving organ such as a beating heart." The research was published in the journal Science. The Secret to Happiness Seems to Depend Upon You, Study Finds Drinking Alcohol Before Hitting The Sauna Could Be a Deadly Combo The Roots of Dementia Trace Back All The Way to Childhood, Experts Say
Reuters
09-05-2025
- Health
- Reuters
Health Rounds: Ultrasound triggers experimental 3D drug-delivery implants
May 9 (Reuters) - (To receive the full newsletter in your inbox for free sign up here) Ultrasound waves can penetrate through thick tissues and print medical implants inside a body, experiments in animals suggest. Researchers created 3D implants using focused ultrasound and ultrasound-responsive bioinks delivered via injection or catheter. The carefully guided ultrasound waves trigger localized heating, slightly above body temperature, that transforms the ink into a gel that can be printed into desired shapes and tailored for functions such as drug delivery and tissue replacement, according to a report published on Thursday in Science, opens new tab. Furthermore, the ultrasound imaging allows for real-time monitoring and customized pattern creation, the researchers said. In one experiment, the researchers printed drug-loaded biomaterials that delivered a chemotherapy drug to cancerous sites in a mouse bladder. They found substantially more tumor cell death for several days compared to animals that received the drug through direct injection. "We have already shown in a small animal that we can print drug-loaded hydrogels for tumor treatment," study leader Wei Gao of Caltech said in a statement. "Our next stage is to try to print in a larger animal model, and hopefully, in the near future, we can evaluate this in humans." A commentary, opens new tab published with the paper notes that refinements are still needed. 'Printing on organs that expand and contract, such as the lungs, heart, and stomach, presents additional challenges,' the commentary authors note. Healthcare workers who wash their scrubs at home may be unknowingly contributing to the spread of antibiotic-resistant infections in hospitals, researchers warned in a report published in PLoS One, opens new tab. To evaluate whether home washing machines successfully decontaminated healthcare worker uniforms, they washed contaminated fabric swatches in six different consumer-grade washing machines in hot water, using rapid and normal cycles. Half of the machines did not disinfect the clothing during a rapid cycle, while one third failed to clean sufficiently during the standard cycle. After each washing, DNA sequencing of biofilm samples from inside the machines revealed the presence of potentially pathogenic bacteria and antibiotic resistance genes. 'Our research shows that domestic washing machines often fail to disinfect textiles, allowing antibiotic-resistant bacteria to survive,' the report's authors said in a statement. Researchers also found that bacteria can develop resistance to domestic detergents, which also increased their resistance to certain antibiotics. They propose that the laundering guidelines given to healthcare workers should be revised to ensure that home washing machines are cleaning effectively. 'If we're serious about transmission of infectious disease via textiles and tackling antimicrobial resistance, we must rethink how we launder what our healthcare workers wear,' the researchers said. (This is an excerpt of the Health Rounds newsletter, where we present latest medical studies on Tuesdays and Thursdays. To receive the full newsletter in your inbox for free sign up here.)
