A new system that could lead to diagnosing Alzheimer’s disease through a blood test was created by a group of researchers from the National University of Singapore (NUS). The system, called APEX (Amplified Plasmonic EXosome), is structured so that it can identify an early molecular marker of Alzheimer’s disease, the aggregated beta-amyloid (Aβ).
It is a technology that according to the researchers is “highly sensitive” and can provide an “accurate diagnosis, comparable to the PET image of the brain.” The latter is the standard for diagnosing Alzheimer’s disease. The difference lies in the fact that a test carried out with the APEX system, according to the researchers, would cost only $30, less than 1% of the cost that must be faced with PET imaging.
The system sees a direct analysis of the blood plasma sample and would also be very simple to use. The results of the two-year study that led to the creation of this method were published in Nature Communications.
However, one of the main features of this system is not in the cost or in the ease of use but in the fact that it allows, according to the researchers, very early diagnosis compared to the classical methods. Precisely the untimely diagnosis of Alzheimer’s disease is one of the main causes of the failure of therapies that need early intervention. A solution can arrive with the PET imaging system or with the cerebrospinal fluid test, but these are too expensive tests that are therefore not widely adopted.
The new test “captures” effectively, and measures the quantities, only the most significant amyloid-beta molecules in the blood sample and at the same time the more “early” ones, in order to analyze the first aggregated forms of this protein to allow detection of the Alzheimer’s even before the classic clinical symptoms appear.
A group of Australian researchers reveals that they have identified the fast cosmic waves related to an explosion that occurred in a distant galaxy 3.6 billion light-years away. This is a discovery that could be of fundamental importance to really understand the mysterious fast radio flashes.
The identification was carried out thanks to the observations of the Australian Square Kilometer Array Pathfinder (ASKAP) radio telescope of the Commonwealth Scientific and Industrial Research Organization (CSIRO), located in the region of Western Australia. This is a result that had long been expected in the astronomical community, a result that then resulted in a study published in Science.
Fast radio flashes are energy emissions caused by a cosmic explosion and are very difficult to intercept because they are emitted on long waves at the end of the electromagnetic spectrum. They are also very powerful so that they can develop in the same millisecond the same amount of energy that the Sun radiates in 10,000 years.
The first FRB was detected in 2007 and since then 85 have been identified, a number which however has not proved sufficient for a total understanding of the phenomenon. The researchers this time used a new method based on new software capable of calculating a billion measurements per second, which made it possible to “capture” these very fast flashes.
The new fast radio flash has been called FRB 180924 and is the first for which the position has been identified in a relatively precise manner. The lightning started from the galaxy Des J214425.25−405400.81. This galaxy was then photographed with the Very Large Telescope of the Southern European Observatory and its distance was measured with the Keck telescope of Hawaii.
Various hypotheses have been made regarding the explosion that these fast flashes generate and one of them sees the formation of a magnetar, a neutron star with a very pronounced magnetic field that is formed by the death of a very massive star. However, this discovery also reinforces the idea that there are two types of FRB, some repeated and others not, which may have completely different origins.
Those that are not repeated are much more difficult to identify but in this case, the researchers were able to identify with extreme precision the position of FRB 180924 locating it at 4000 parsecs (each parsec corresponds to about 3.26 light-years) from the galactic center of a galaxy distant from us 3.6 billion years ago.
A group of scientists has discovered that dimethyltryptamine (DMT), a molecule that is an active ingredient that is present in some hallucinogenic plants, is produced by two enzymes of neurons in the mammalian brain.
Dimethyltryptamine is historically used by various cultures during rituals that include hallucinogenic states, first of all those made by different indigenous peoples of the Americas for their religious or sacred ceremonies. It was then synthesized in the laboratory only in 1931.
One of the authors of the study, Jimo Borjigin, a researcher at the University of Michigan’s department of molecular and integrative physiology, turned to the work of another researcher, Rick Strassman. In the mid-1990s the latter conducted several experiments on humans subjected to DMT by intravenous injection, experiments that convinced him that the pineal gland in our body could naturally produce and secrete this substance. Borjigin resumed this work thinking that it would be relatively easy to locate the substance in this gland using a fluorescence detector. He therefore performed experiments on rats by collecting pineal gland samples from rodents and analyzing them in the laboratory. The analysis confirmed the presence of DMT, and this was already in 2013.
However, the researcher was not satisfied: he wanted to understand in what area of the body the substance was synthesized. He then worked with his student Jon Dean, lead author of a further study just published in Scientific Reports, performing experiments using a process called in situ hybridization that involves analyzing DNA strands to localize specific RNA sequences in a tissue.
They discovered that it is the enzymes of certain brain neurons that synthesize DMT. They also discovered that this substance did not end up only in the pineal gland but is also found in other parts of the brain, such as the neocortex and the hippocampus.
Finally, they discovered that the levels of this substance increase in rats subjected to cardiac arrest, which would justify the near-death experiences that in some ways can be considered similar to the hallucinogenic experiences that the substance produces when it is taken through plants.