Category: Applied Sciences

A new test for urinary tract infections that is much more practical and faster, so much so that results could be obtained in as little as 25 minutes, was developed by a group of biological engineers at the University of Bath. According to the researchers, the new test can analyze urine and identify the presence of pathogenic bacteria, such as Escherichia coli, in just 25 minutes, a time that is faster than any other test, of the same level of accuracy, ever created.

Such a test could be very useful especially in developing countries and in remote regions where other types of tests are not possible and where the only method is to send the urine sample to distant structures, with a lengthening of time. The test was created mainly to verify the presence of Escherichia coli in urine, a bacterium that can lead to urinary tract infections and is usually treated with antibiotics.

The study, published in Biosensors and Bioelectronics, describes how the test uses antibodies to identify bacterial cells. The test involves placing a small urine sample on a plastic strip that contains an immobilizing antibody to recognize the cells of Escherichia coli bacteria. Thanks to a special enzyme added to the strip, a colour change takes place which can be detected by a smartphone camera.

This is a faster method than the microbiological ones that are currently used. The device that allows you to perform the test is also very small, and therefore almost portable, something that could allow rapid diagnosis of urinary tract infections, in turn something that would be very important and that would allow prescriptions much more proven than antibiotics.

We have always heard that polystyrene, one of the world’s most widely used plastics, has not been decomposed for thousands of years and may, therefore, be a major pollutant.

However, a new study published in the journal Environmental Science & Technology Letters shows that if polystyrene is exposed to sunlight, it can “confuse” it in shorter time frames, from decades to centuries.

Polystyrene or polystyrene is now used in many areas, in expanded forms, especially in packaging, but also in non-foam form for the construction of many facilities, from disposable razors to CD cases.

It cannot be degraded by any microbe and, above all, this aspect has forced scientists to evaluate, if not conservatively, its duration over millennia. It seems that a new study by Colin Ward and his colleagues at the Woods Hole Oceanographic Institution has reduced this limit.

The researchers conducted an experiment by placing five samples of polystyrene in water, which is widely available on the market. They then subjected these parts of the modeling of sunlight three times brighter than the same sunlight that beats at the equator to speed up the simulation time.

The researchers found that this simulated light partially oxidized all the samples, turning some of them into organic carbon. According to researchers, the same process could take decades in the natural environment and at latitudes ranging from 0° to 50°N (mainly from the equator to the upper boundary of the United States).

Therefore, scientists are estimating a period of time that will take centuries, not millennia, for complete degradation.

Researchers believe that this limit can be further reduced by playing with the amount and quality of additives commonly found in polystyrene. With new technologies, these additives can be easily controlled in the future.

According to a new study, consumer-quality 3D printers emit particles into the atmosphere that can adversely affect air quality. This is mainly due to indoor pollution, such as in offices.

The study, published in the journal Environmental Science & Technology, was based on the results of several tests conducted using 3D printers to measure the effects on the respiratory system of humans. As one of the authors of the study, Professor Rodney Weber of Earth School of Technology, Georgia State Institute of Technology, notes, the tests “have shown that there is a toxic reaction to particles of different types of fibers used by these 3D printers.”

The researchers analyzed the chemical composition of these particles, as well as their toxic potential. These emissions are due to the peculiarities of 3D-printers. These devices apply and melt layers on layers to create an object, and it is the heating of plastic that causes the emission of ultrafine particles into the air around the printer.

The warmer the temperature used by the printer to melt the fibers, the higher the emission level. The largest source of radiation is acrylonitrile butadiene styrene (ABS), which requires a higher melting point to be reached. Polymalic lactic acid (PLA), which requires a lower temperature, produces the least emissions.

Tests for toxicity have shown that PLA particles are more toxic than ABS particles. However, more ABS particles were emitted by printers during the tests, so Weber himself explains that these emissions are ultimately of greater concern.

There are also concerns about the “additives” added to fibers by manufacturers to achieve certain characteristics that are largely hidden. According to Weber, these additives can affect the amount of emissions for ABS. This means that ABS yarns purchased from one manufacturer can produce more harmful emissions than one from another.

Links:

https://www.news.gatech.edu/2019/10/07/particles-emitted-consumer-3d-printers-could-hurt-indoor-air-quality

https://pubs.acs.org/doi/10.1021/acs.est.9b04168

As proof that intestinal microbiomes are becoming increasingly important in the scientific and biomedical fields, a team of researchers at the Lincoln Laboratory of the Massachusetts Institute of Technology is implementing a new project to create what the press release calls the “ideal artificial intestine.”

Today, in fact, many studies of the intestine, and especially the trillion bacteria in it, cannot be done because it is impossible to test on a model that looks like a real analogue. Artificial platforms, which today imitate the human intestines, are not actually accurate and are not cheap at all. This means that many laboratories cannot afford it.

MIT researchers are trying a new way: they will try to mimic, at least in part, the great complexity of the human intestines, including all those conditions that must be present to survive and test bacterial samples. Growing a microbiomal sample and keeping it alive in a laboratory is a feat that no one has yet been able to accomplish, reminds David Walsh of the Group of Biological and Chemical Technologies, one of the scientists who led this group.

They have already built a platform of permeable silicone rubber with various parts made of other plastics, including polystyrene, all relatively inexpensive and easily manufactured.
The platform is based on oxygen and other slime control components, another important element that allows bacteria to reproduce in the intestine.

“The final system will allow us to face real-world problems,” says Walsh himself, who suggests that this new system will allow us to take new steps forward and to understand the strong connection between the intestine itself and the brain.

Links:

http://news.mit.edu/2019/artificial-gut-aims-to-expose-human-microbiome-1003