Certain gut bacteria reside in colorectal tumors, but the species differ depending on a patient’s age, offering hope that our gut tenants could serve as early warning signs of cancer in young people.
Category: biotech/medical – Page 405
Musk said that the first human patient implanted with a Neuralink chip last month “is able to… move the mouse around the screen just by thinking.”
Nucleases present a formidable barrier to the application of nucleic acids in biology, significantly reducing the lifetime of nucleic acid-based drugs. Here, we develop a novel methodology to protect DNA and RNA from nucleases by reconfiguring their supramolecular structure through the addition of a nucleobase mimic, cyanuric acid. In the presence of cyanuric acid, polyadenine strands assemble into triple helical fibers known as the polyA/CA motif. We report that this motif is exceptionally resistant to nucleases, with the constituent strands surviving for up to 1 month in the presence of serum. The conferred stability extends to adjacent non-polyA sequences, albeit with diminishing returns relative to their polyA sections due to hypothesized steric clashes. We introduce a strategy to regenerate stability through the introduction of free polyA strands or positively charged amino side chains, enhancing the stability of sequences of varied lengths. The proposed protection mechanism involves enzyme failure to recognize the unnatural polyA/CA motif, coupled with the motif’s propensity to form long, bundling supramolecular fibers. The methodology provides a fundamentally new mechanism to protect nucleic acids from degradation using a supramolecular approach and increases lifetime in serum to days, weeks, or months.
Recently approved gene therapies offer patients one-time, potentially curative treatments for genetic diseases such as sickle cell anemia and beta thalassemia. But “one-time” miracle solutions can often be multi-month affairs, require millions of dollars, and cause painful side effects. What if that doesn’t have to be the case?
In utero gene editing, or prenatal somatic cell genome editing, envisions treating a fetus diagnosed with a genetic disease before birth, thereby preventing that entire protocol and the onset of symptoms in the first place. It would also challenge the need for the ethically fraught enterprise of embryo editing, as the treatment would only make edits in the DNA of the individual fetus — edits which would not be passed on in a heritable way.
Watch this video to learn more about in utero gene editing, how it works, and why scientists believe it might be an advantageous approach to treating certain genetic diseases.
Gene editing technology could revolutionize the treatment of genetic diseases, including those that affect the mitochondria—cell structures that generate the energy required for the proper functioning of living cells in all individuals. Abnormalities in the mitochondrial DNA (mtDNA) could lead to mitochondrial genetic diseases.
Targeted base editing of mammalian mtDNA is a powerful technology for modeling mitochondrial genetic diseases and developing potential therapies. Programmable deaminases, which consist of a custom DNA-binding protein and a nucleobase deaminase, enable precise mtDNA editing.
There are two types of programmable deaminases for genome editing: cytosine base editors and adenine base editors, such as DddA-derived cytosine base editors (DdCBEs) and transcription activator-like effector (TALE)-linked deaminases (TALEDs). These editors bind to specific DNA sites in the mitochondrial genome and convert bases, resulting in targeted cytosine-to-thymine (C-to-T) or adenine-to-guanine (A-to-G) conversions during DNA replication or repair. However, the current gene editing approaches have many limitations, including thousands of off-target A-to-G edits while using TALEDs.
For more information on the Somatic Cell Genome Editing program, visit our website at: https://commonfund.nih.gov/editing Follow this link to for a version of the video that does not include audio descriptions: • NIH Common Fund Somatic Cell Genome E… Thousands of human diseases are caused by changes, or mutations, to the body’s DNA. What if we could treat all these diseases by diving into our living cells to correct the mistakes? The Somatic Cell Genome Editing program aims to make that happen. Recently, researchers have made great progress in correcting DNA mutations using a technique called genome editing, and the first tests of genome editing for human diseases are starting. However, there are still some challenges to achieve safe and effective genome editing in patient cells. The Somatic Cell Genome Editing, or SCGE, program was launched by the NIH Common Fund to develop quality tools to perform safe and effective genome editing in human patients. The SCGE program will make more genome editing tools available to researchers to develop better packages to deliver the tools to the right cells, design new tests for the safety and efficacy of genome editing, and make all of the information available to the scientific community to drive future discoveries and cures for patients.
“The timing of our study couldn’t be more critical, and its implications are profound,” said Dr. Yaguang Wei.
What impact can severe air pollution have on the health of senior citizens? This is what a recent study published in BMJ hopes to address as a team of researchers led by Harvard University investigated how over-exposure to fine particulate matter (PM2.5) for senior citizens could lead to hospitalizations for seven major cardiovascular disease (CVD) subtypes, including heart failure, ischemic heart disease, arrhythmia, cerebrovascular disease, cardiomyopathy, abdominal aortic aneurysms, and thoracic aortic aneurysms. This study holds the potential to help scientists, medical professionals, and the public better understand the long-term health risks for severe air pollution, especially with climate change effects continuing to increase worldwide.
For the study, the researchers analyzed 59,761,494 Medicare fee-for-service recipients 65 years of age and older between 2000 and 2016 and compared them to air pollution data during that same period. Each of the recipients were tracked every year until their first hospitalization for one of the seven major CVD subtypes, and the researchers produced a map based on the recipients’ ZIP codes. In the end, the researchers discovered the average exposure time from air pollution to a recipients’ first hospitalization was three years, in addition to determining their exposure to PM2.5 was above the acceptable threshold outlined by the World Health Organization (WHO).
Researchers at the Technion – Israel Institute of Technology have discovered a way to potentially predict the success of immunotherapy treatment in cancer patients.
Immunotherapy involves encouraging the body’s immune system to attack the cancer cells. This can be complicated by the cancer cells “hiding” within the body or the immune system itself being reluctant to attack the cancer cells due to the threat to healthy surrounding cells.
And, while it has been proven to be a successful treatment against cancer, immunotherapy is only effective in around 40 percent of patients.
Dr. David Cohen comments on 10-year results from a trial of transcatheter vs. surgical aortic valve replacement:
Over the past decade, transcatheter aortic valve replacement (TAVR) has evolved from a niche procedure to treat severe aortic stenosis in high-risk patients to a mainstream procedure that is also performed in intermediate-and low-risk patients. With this evolution in practice, the large number of younger patients with life expectancies 10 years now receiving TAVR has raised concerns about its durability and patients’ long-term outcomes. Now, 10-year results are available from the NOTION trial of TAVR versus surgical aortic valve replacement (SAVR) that was conducted between 2009 and 2013 (NEJM JW Cardiol May 29 2015 and J Am Coll Cardiol 2015; 65:2184).
Two hundred eighty patients aged 70 years (mean age, 79 years; mean predicted risk of surgical mortality, 3%) were randomized to SAVR using any commercially available bioprosthesis or TAVR using the first-generation self-expanding CoreValve device. At 10-year follow-up, there was no significant between-group difference in the composite of death, stroke, or myocardial infarction (66% for both groups) or any of the individual components. Rates of bioprosthetic valve failure and repeat valve intervention were also similar. However, the rate of bioprosthetic valve dysfunction was lower with TAVR, largely reflecting lower rates of patient–prosthesis mismatch. The rate of structural valve deterioration was lower with TAVR as well, driven mainly by lower transvalvular gradients with TAVR that emerged early and persisted throughout follow-up.
Although limited by its modest sample size, the NOTION trial provides the longest available follow-up of any TAVR-versus-SAVR randomized trial to date. Overall, the results provide reassurance that there are no important differences in major clinical outcomes between the two strategies, and the echocardiographic data suggest sustained differences in hemodynamic performance in favor of TAVR. Nonetheless, given the advanced age of the patients at the time of enrollment, we should be cautious in extrapolating these findings to younger patients with severe aortic stenosis or to patients with bicuspid aortic valve disease (who were excluded from NOTION). These findings emphasize the tension between ongoing innovation and the desire for long-term outcomes data for our cardiac devices.
Imagine being able to build an entire dialysis machine using nothing more than a 3D printer.
This could not only reduce costs and eliminate manufacturing waste, but since this machine could be produced outside a factory, people with limited resources or those who live in remote areas may be able to access this medical device more easily.
While multiple hurdles must be overcome to develop electronic devices that are entirely 3D printed, a team at MIT has taken an important step in this direction by demonstrating fully 3D-printed, three-dimensional solenoids.