|Year : 2017 | Volume
| Issue : 2 | Page : 162-163
|Date of Web Publication||18-May-2017|
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
. Medical news
. Curr Med Issues 2017;15:162-3
Medical News – Innovations and discoveries in Medicine
Low-cost Malaria diagnosis with a children's toy
A centrifuge is a vital component of laboratory testing for malaria. The centrifugal force of the machine separates the red cells and other blood components from the clear plasma so that they can be examined for malarial parasites.
There is however, a problem – a centrifuge machine costs anywhere between 65,000 to 3 lakh rupees, an amount that many developing countries cannot afford – to buy or to maintain. This was what Manu Prakash, a biomedical engineer at Stanford discovered during a visit to Uganda. The machines also require electiricity, and frequent interruptions of the electrical supply did not help matters. He wondered if it would be possible to use a cheaper alternative that does not use electricity to perform the same function. Other researchers had used egg-beaters and salad spinners to address this issue but these instruments could not achieve rotation speeds greater than 1200 rpm, which was far slower than the >10,000 rpm of a centrifuge machine. Prakash and his team wanted something faster and drew inspiration from a childhood toy – the whirligig. This toy typically has a central disc that spins when a person pulls on strings that pass through the center. On filming the rotating disc with a high-speed camera, the team was astounded to see that the disc achieved speeds of over 10,000 rpm, comparable with a commercial centrifuge. The team used computer simulation software to study the physics of the toy and used the principles of supercoiling DNA strands to understand how hand-forces move from the coiling strings to power the spinning disc. They succeeded in creating a prototype which achieved rotational speeds of up to 125,000 rpm. “To the best of my knowledge, it's the fastest spinning object driven by human power,” said Manu Prakash.
The device made of paper and string, costing less than a US dollar (around 20 cents), was tested in the field and they found that it could be used to separate blood components similar to a centrifuge, using just human power. This was achieved by spinning the sample in a capillary coated with acridine orange dye. By examining the capillary under a microscope, the glowing malarial parasites could be easily identified. The whole process took about 15 minutes, used no electricity and was very inexpensive. The findings of the team describing the instrument were published in the journal 'Nature Biomedical Engineering' in the January 2017 issue. The team called the gadget a 'Paperfuge' and are currently conducting a field validation trial for malaria diagnostics with PIVOT and Institut Pasteur, community-health collaborators based in Madagascar.
Newby K. Inspired by a whirligig toy, Stanford bioengineers develop a 20-cent, hand-powered blood centrifuge. Stanford News. Jan 10, 2017. Available at http://news.stanford.edu/2017/01/10/whirligig-toy-bioengineers-develop-20-cent-hand-powered-blood-centrifuge/ [Last accessed on 20th April 2017
Bhamla MS, Benson B, Chai C, Katsikis G, Johri A, Prakash M. Hand-powered ultralow-cost paper centrifuge. Nature Biomedical Engineering. 2017;1:09.
Medical News – Innovations and discoveries in Medicine
2016 Nobel Prize in Medicine - Autophagy
The Nobel prize in Physiology or Medicine for the year 2016 was awarded to a Japanese cell biologist, Yoshinori Ohsumi for his work on autophagy, the body's internal recycling system.
The following is an excerpt from the press release of the Nobel Committee.
This year's Nobel Laureate discovered and elucidated mechanisms underlying autophagy, a fundamental process for degrading and recycling cellular components. The word autophagy originates from the Greek words auto-, meaning “self”, and phagein, meaning “to eat”. Thus, autophagy denotes “self eating”. This concept emerged during the 1960's, when researchers first observed that the cell could destroy its own contents by enclosing it in membranes, forming sack-like vesicles that were transported to a recycling compartment, called the lysosome, for degradation. Difficulties in studying the phenomenon meant that little was known until, in a series of brilliant experiments in the early 1990's, Yoshinori Ohsumi used baker's yeast to identify genes essential for autophagy.
Autophagy – an essential mechanism in our cells
After the identification of the machinery for autophagy in yeast, a key question remained. Was there a corresponding mechanism to control this process in other organisms? Soon it became clear that virtually identical mechanisms operate in our own cells. The research tools required to investigate the importance of autophagy in humans were now available. Thanks to Ohsumi and others following in his footsteps, we now know that autophagy controls important physiological functions where cellular components need to be degraded and recycled.
Juleen Zierath, a member of the Nobel committee explained the day-to-day importance of autophagy in maintaining healthy cells in the body: “Every day we need to replace about 200-300g of protein in our bodies. Every two to three months, every protein in our body turns over. Because of autophagy, these 200-300g of proteins are made. We are eating proteins every day, about 70g, but that's not enough to take care of the requirement to make new proteins. Because of this machinery, we're able to rely on some of our own proteins, maybe the damaged proteins or the long-lived proteins, and they are recycled with this sophisticated machinery so that we can sustain and we survive.”
Autophagy can rapidly provide fuel for energy and building blocks for renewal of cellular components, and is therefore essential for the cellular response to starvation and other types of stress. After infection, autophagy can eliminate invading intracellular bacteria and viruses. Autophagy contributes to embryo development and cell differentiation. Cells also use autophagy to eliminate damaged proteins and organelles, a quality control mechanism that is critical for counteracting the negative consequences of aging.
Disrupted autophagy has been linked to Parkinson's disease, type 2 diabetes and other disorders that appear in the elderly. Mutations in autophagy genes can cause genetic disease. Disturbances in the autophagic machinery have also been linked to cancer. Intense research is now ongoing to develop drugs that can target autophagy in various diseases. Autophagy has been known for over 50 years but its fundamental importance in physiology and medicine was only recognized after Yoshinori Ohsumi's paradigm-shifting research in the 1990's. For his discoveries, he is awarded this year's Nobel Prize in physiology or medicine.
Source: The Nobel Assembly at Karolinska Institutet press release. Available at https://www.nobelprize.org/nobel_prizes/medicine/laureates/2016/press.html
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