Cancer detected in 10 minutes by a universal test? – Futura-Sciences


Stir the blood with a pink liquid and you'll know immediately if you have cancer or not. This is the revolutionary promise of Australian researchers, who believe they have found a widely accessible and affordable way to detect the disease.

Most cancer screening tests are now performed by biopsy: a tissue sample or tufts of cells. A tumor can be benign or malignant. "Data-url =" / health / definitions / tumor-medicine-2540 / "data-more =" Read the definition ">cancer it is taken to determine whether or not it contains tumor cells, more often by analyzing the structure of DNA
DNA is a very long molecule, composed of a succession of nucleotides hooked up by the phosphodiester bonds. There are four … "data-image =" "data-url = "/ health / definitions / medecine-adn-87 /" data-more = "More information">DNA or qPCR (quantitative PCR). An invasive and expensive technique that scientists from the University of Queensland, Australia, believe have found an alternative. The latter presented on December 5 in the newspaper Communications of nature a fast e cheap to detect traces of the disease.

A liquid that changes color in 10 minutes

The test is based on the presence or absence of a methyl group on the DNA of a cell, a process called methylation. These sequences are fixed on some specific sites called CpG islands and alter the activity of certain genes. In normal cells, these methyl groups are regularly distributed within the cell. But in a cancerous cell, DNA is largely denuded and methyl groups grouped on some CpG islands. The researchers found that these narrow clusters form a particular nanostructure that adheres to solid surfaces. The DNA of the cancer cells attacks like this nanoparticles of gold. Researchers have created a test based on water and nanoparticles that make the water pink. In the presence of abnormal methyl groups, the liquid you're pink. If it turns blue, it means that the cell is healthy.

This approach has been tested on over 100 human samples, with 72 patients with different tumors and 31 healthy individuals. The test showed a sensitivity of 90%, ie it detects 90% of cases with 10% of false positives.

Like most blood tests, the markers are researched here in theCirculating DNA, what the cancer cells release into the blood when they die. This circulating DNA is much higher in the advanced stage of cancer than in the preliminary phase, which means that the test is probably less effective in detecting cancer very soon. Furthermore, it is not able to determine what kind of cancer it is. " Our test will be used to make a first selection to conduct further tests Says Laura Carrascosa, a researcher at the University of Queensland.

Blood analysis, the Grail of cancer research

This is not the first time blood screening test cancer is announced. In January 2018, the researchers had already submitted a test called SEEK cancer, able to identify eight types of cancer by analyzing the circulating DNA. The American startup Grail also promises a blood test based on automatic DNA sequencing Street the automatic learning. But these approaches require very expensive and highly specialized equipment. If you use a precious metal, the method of gold nanoparticles, in small quantities in the liquid, would be paradoxically much cheaper.

It is known to detect the presence of a tumor from a blood test by detecting the majority of proteins or peptides (protein fragments) that are specifically recognized by antibodies and also by some … "data-url =" / health / definitions / medecine-antigen-95 / "data-more =" More information ">antigens Features. But the method is long and delicate. It is necessary to centrifuge the blood to separate the cells (structure of the red blood cells
A red blood cell is a biconcave discoidal cell with no nucleus, mitochondria and … "data-image =" / 4 /7e41a2edcc_50034233_globule-red-dr-07.jpg "data-url =" / health / definitions / medicine-globule-red-715 / "data-more =" More information ">Red blood cells, white, etc.) of plasma in biology
Liquid part of the blood which represents about 55% of its volume. Plasma is composed of water and contains lipids (fats), hormones, factors of … "data-image =" midioriginal / 5 / 1/9 / 519c1b8d6a_50034460_plasma-02.jpg "data-url =" / health / definitions / medecine-plasma-2871 / "data-more =" More information ">plasmawhich must therefore undergo a complex chemical analysis. The work lasts several days and can only be done in a specialized laboratory. Moreover, the accuracy is average and the antigen must be present in sufficient quantity to be highlighted, otherwise it could remain an ambiguity.

What to remember

  • Cancer research is usually performed by biopsy, an invasive and expensive method.
    Researchers developed a test to detect methylation of circulating DNA in less than 10 minutes.
    Much research is aimed at detecting cancer Street a simple blood sample for a previous treatment.

Detects cancer within minutes with nanotechnology

Article by Jean-Luc Goudet published 12/15/2009

A team from Yale University has developed a simple, accurate and fast blood test technique that can identify the biomarkers of … "data-image =" https: //fr.cdn. "data-url =" / health / definitions / medecine-cancer-sein-9270 / "data-more =" Read more ">breast cancer or the function of the prostate
The prostate is a gland that contributes, through the secretion of the prostatic fluid, to the production of sperm. The prostatic fluid (which corresponds to 20% of the semen volume) is colorless, isotonic, containing … "data-image =" midioriginal / f / 7 / f7003f2fb3_50035154_prostate-dr.jpg "data-url =" / health / definitions / biology-prostate-6144 / "data-more =" More information ">prostate. The method, which uses a microchip and nanowires, could be applied to other tumors or even to cardiovascular diseases
Cardiovascular diseases are favored by:

smoke, obesity, an ugly … "data-image =" "data-url = "/ health / definitions / heart-disease-cardiovascular-15398 /" data-more = "More information">cardiovascular diseases.

For several years, Mark Reed and Tarek Fahmy, of Yale University, keep it going electronic sensors can detect some The so-called simple covalent bond … "data-image =" "data-url =" / sciences / definitions / chemistry-molecule-783 / "data-more =" More information ">molecules in a liquid solution and applied to diagnosis doctor. In this laboratory on a chip (or lab-on-a-chip, LOC), the solution flows into a miniaturized device, using the microfluidics, this science of the circulation of a fluid in a volume: cubic meter and liter
In the international system, the volume unit is … "data-image =" . jpg "data-url =" / sciences / definitions / physical-volume-15919 / "data-more =" More information ">volume very small.

In the spatial domain, a star sensor is an optoelectronic device for the orientation of satellites. "Data-image =" 6/3/4 / 6349c4ee96_50036247_capteurrecopesca-image-node-full.jpg "data-url =" / tech / definitions / sensor-technology-8460 / "data-more =" Read the definition ">sensors the most classical, the desired substance interacts with botany
In horticulture, support or base on which plants can grow. It can be sediment, mud, rocks … as well as granules specific to a pond … "data-image =" / midioriginal / d / d / c / ddc09ec4e8_50034245_plante-terre-dr-01.jpg "data-url =" / sciences / definitions / chemistry-substrate-816 / "data-more =" More information ">background and solve in certain places. It can then be detected by a marker, for example a fluorescent marker, which binds specifically to it. The Yale University team is studying purely electronic nanosensors for faster analysis. The idea is not new. IBM, for example, recently introduced the prototype of a " DNA chips ", Able to sequencing a DNA chain.

A portable diagnostic system

Today, a group gathered around these two researchers publishes the details of a first concrete realization in the magazine Nature Nanotechnology. The performances are quite spectacular. This small chip detects the presence of antigens characteristic of breast cancer and prostate cancer in less than twenty minutes: survival and risk factors
The 5-year survival is estimated at 84%; is 70 … "data-image =" .jpg "data-url =" / health / definition / cancer-cancer-prostate-15990 / "data-more =" More information ">prostate cancer in a sample of 10 microliters of blood obtained without any preparation.

The secret, the authors explain, lies in the circulation of the liquid. Within the sensor, the purification and analysis steps are separate. The blood, with all its components, is first filtered in a first compartment. After a washing step, the remaining purified liquid enters the analysis area. This is composed of general nanowires
Symbol: SiOnatomic number: 14Electrons per energy level: 2, 8, 4Maxic atom: 28.0855 Most stable UIsotopes: 28Si stable with 14 … "data-image =" https: //en.cdn.v5. "data-url =" / sciences / definitions / silicon-chemistry-14517 / "data-more = "Further information">silicon on which the substance to be detected is fixed " This two-step separation isolates the detector from the complex blood environment "The researchers specify.

The result is a very high sensitivity, which allows to detect very low concentrations of markers. This sensor would be able to detect a grain of salt diluted in a pool, say the authors. The speed of analysis and the fact that it can be performed on a fresh blood sample without preparation completely changes the way to conduct this type of test. It could be practiced quickly, in hospital or even by a doctor. Furthermore, this chip could be used on a wide variety of tumors and even to detect cardiovascular disease.

Interested in what you just read?

Subscribe to the newsletter The newspaper : our latest news of the day.

It will interest you too



Please enter your comment!
Please enter your name here

This site uses Akismet to reduce spam. Learn how your comment data is processed.