To reduce false positive results from the initial study, the researchers first used a blood test to identify high-risk individuals. They added a dementia-specific biomarker, tau protein, for participants shown to have Alzheimer’s in the first step. The second analysis was carried out in cerebrospinal fluid extracted from the spinal cord — an invasive procedure that the team is working to eliminate from the next phase of research. If both biomarkers were positive, it was determined that the presence of Alzheimer’s disease was highly likely.
According to Gerwert: “Through the combination of both analyses, 87 of 100 Alzheimer’s patients were correctly identified in our study. And we reduced the number of false positive diagnoses in healthy subjects to 3 of 100. Now, new clinical studies with test participants in very early stages of the disease can be launched. Recently, two major promising studies have failed, especially Crenezumab and Aducanumab – not least because it had probably already been too late by the time therapy was taken up. The new test opens up a new therapy window.”
Researcher Andreas Nabers added: “Once amyloid plaques have formed, it seems that the disease can no longer be treated. We are now conducting in-depth research to detect the second biomarker, namely tau protein, in the blood, in order to supply a solely blood-based test in future.”
Buganim and colleagues discovered a combination of five genes that, when inserted into skin cells, reprogram the cells into the three early embryonic cell types–iPS cells which create fetuses, placental stem cells, and stem cells that develop into other extra-embryonic tissues. The transformations take about one month.
To uncover the molecular mechanisms that are activated during the formation of these cell types, the researchers analyzed changes to the genome structure and function inside the cells when the five genes are introduced. They discovered that during the first stage, skin cells lose their cellular identity and then slowly acquire a new identity of one of the three early embryonic cell types, and that this process is governed by the levels of two of the five genes.
This discovery may enable creation of entire human embryos out of human skin cells, without the need for sperm or eggs. It will also impact the modeling of embryonic defects and the understanding of placental dysfunctions. It could address fertility problems by creating human embryos in a petri dish.
The goal is a communication method for those with disease and paralysis.
According to Chang: “For the first time, this study demonstrates that we can generate entire spoken sentences based on an individual’s brain activity.”
Berkeley’s Bob Knight has developed related technology, using HFB activity to decode imagined speech to develop a BCI for treatment of disabling language deficits. He described this work at the 2018 ApplySci conference at Stanford.
PTSD is typically determined by bias-prone clinical interviews or self-reports.
The team recorded standard diagnostic interviews of 53 Iraq and Afghanistan veterans with military-service-related PTSD, as well as 78 veterans without the disease. The recordings were then fed into voice software to yield 40,526 speech-based features captured in short spurts of talk, which were then sifted for patterns.
The program linked less clear speech and a lifeless metallic tone with PTSD., While the study did not explore disease mechanisms behind PTSD, the team believes that traumatic events change brain circuits that process emotion and muscle tone, affecting a person’s voice.
A biopsy of fatty tissue was taken from patients. Cellular and a-cellular materials were separated. While the cells were reprogrammed to become pluripotent stem cells, the extracellular matrix were processed into a personalized hydrogel that served as printing “ink.” After being mixed with the hydrogel, the cells were efficiently differentiated to cardiac or endothelial cells to create patient-specific, immune-compatible cardiac patches with blood vessels and, subsequently, an entire heart.
Dvir believes that this “3D-printed thick, vascularized and perfusable cardiac tissues that completely match the immunological, cellular, biochemical and anatomical properties of the patient” reduces the risk of implant rejection.
The team now plans on culturing the printed hearts and “teaching them to behave” like hearts, then transplanting them in animal models.
To create their intracellular calcium sensors, the researchers used manganese as a contrast agent, bound to an organic compound that can penetrate cell membranes, containint a calcium-binding chelator.
Once inside the cell, if calcium levels are low, the calcium chelator binds weakly to the manganese atom, shielding the manganese from MRI detection. When calcium flows into the cell, the chelator binds to the calcium and releases the manganese, which makes the contrast agent appear brighter in an MRI.
The technique could also be used to image calcium as it performs in facilitating the activation of immune cells, or in diagnostic brain or heart imaging.
The technology consists of an ultra-thin and miniaturized optical chip that, coupled with a standard CMOS camera and powered by image analysis. It is based on metasurfaces. At a certain frequency, these elements are able to squeeze light into extremely small volumes, creating ultrasensitive optical ‘hotspots’.
When light shines on the metasurface and hits a molecule at one of these hotspots, the molecule is detected immediately, changing the wavelength of the light that hits it. By using different colored lights on the metasurface and taking a photo with a CMOS camera, the researchers cn count the number of molecules in a sample, and learn exactly what is happening on the sensor chip. First author Filiz Yesilkoy said: “We then use smart data science tools to analyze the millions of CMOS pixels obtained through this process and identify trends. We’ve demonstrated that we can detect and image not just individual biomolecules at the hotspots, but even a single graphene sheet that’s only one atom thick.”
The team also developed a second, simpler, but less precise, version of the system, where the metasurfaces are programmed to resonate at different wavelengths in different regions.
According to Altug: “Light possesses many attributes – such as intensity, phase and polarization – and is capable of traversing space. This means that optical sensors could play a major role in addressing future challenges – particularly in personalized medicine.”
Like normal stem cells, cancer stem cells have the ability to rebuild a tumor, even after most of it has been removed, leading to cancer relapse and metastasis.
According to Parada: “The pharmaceutical industry has traditionally used established cancer cell lines to screen for new drugs, but these cell lines don’t always reflect how cancer behaves in the body. The therapies that are currently in use were designed to target cells that are rapidly dividing. But what we’ve concluded in our studies is that glioblastoma stem cells divide relatively slowly within tumors, leaving them unaffected by these treatments.”
Even if most of the tumor is destroyed, the stem cells allow it to regrow.
The team discovered a drug, which they called Gboxin, that effectively treated glioblastoma in mice, and killed human glioblastoma cells. They then discovered that Gboxin killed cancer stem cells by starving them of energy – . by preventing cells from making ATP through oxidative phosphorylation in mitochondria. When Gboxin accumulates within cancer stem cells, it essentially strangles the mitochondria and shuts energy production down.
The next step is to determine that Gboxin will be able to cross the blood-brain barrier, and potential side effects of the drug.
Xia Huimin and Guangzhou Women and Children’s Medical Center researchers used AI to read 1.36 million pediatric health records, and diagnosed disease as accurately as doctors, according to a recent study.
Common childhood diseases were detected after processing symptoms, medical history and other clinical data from this massive sample. The goal is the diagnosis of complex or rare diseases by providing more diagnostic predictions, and to assist triage patients.