Vaccine | Definition, Types, History, & Facts

Why Are Treatments That Were Developed For Malaria Now Used For Lupus?

Most physicians with experience in lupus agree that antimalarial treatments such as hydroxychloroquine (Plaquenil), chloroquine (Aralen) or quinicrine (Atabrine) should be used long-term, year-after-year, in all lupus patients who can tolerate them. Why?  

The answer is that these drugs have a range of effects on people, so what they do for malaria is not necessarily the same as what they do for lupus. And yet, there are similarities.

How chloroquine treats malaria

Malaria is caused by a parasite, usually found in tropical regions, that infects humans after they have been bitten by a mosquito. This parasite is transmitted directly from the saliva of the mosquito into the bloodstream of a person who has been bitten. Under the microscope a malaria parasite can actually be seen literally crawling inside of people's red blood cells.

In order to survive, the malaria parasite has to break down a part of the red blood cell called hemoglobin, but this results in toxic by-products which need to be processed and contained by the malaria parasite. The malaria parasite has a little digestive pouch inside it, rather like a primitive stomach, that turns the toxic products into crystals. This provides a way to contain them and keep them from harming the parasite. Chloroquine stops this from happening and even binds directly to the toxic product to disrupt and break up the malaria invader.

All cells, whether parasitic or human, must break down and recycle substances that come in from the blood stream in order to survive. Just like a malaria parasite, the specialized proteins that work for human cells are stored in little acid filled protective pouches inside the cell called lysosomes. Antimalarials go directly into these lysosomes and decrease the acid levels in there that the digestive proteins require in order to work best. In doing so, antimalarials can really gum up some critical activities of hyperactive immune cells.

How chloroquine inhibits overactive immune cells

Our DNA is the blueprint for every protein in the body. Thymine is one of the building blocks of DNA and is needed to replenish new cells all over the body and to build the armies of immune cells we need to fight disease (which are the same cells that we wish would calm down a little in lupus). Chloroquine inhibits the ability of cells to take in and process thymine. This may keep immune cells from regenerating out of control.

As you can see, when you put any substance into a cell it has complicated chemical processes in place to break it down, use some of it for nutrition, recycle parts of it, and dispose of the waste. This is true whether the cell is a parasite trying to survive by eating human red blood cells, or a human cell. Human cells have a big job to do because we humans are complicated beings. We must deal with hostile invaders (bacteria, viruses, parasites), as well as the good (or bad) things that we put into our bodies on purpose, in the form of food and medicine.  

What is hydroxychloroquine?

Some of the breakdown products of medicines also are useful as treatments, even without giving the "parent" drug initially. Hydroxychloroquine (Plaquenil) is a breakdown product of chloroquine, and is, in fact, the most common antimalarial given to treat lupus.

How hydroxychloroquine works to fight lupus

Hydroxychloroquine has a number of effects on the immune system. Recently, hydroxychloroquine has been found to interfere in the internal communications of an immune cell, by inhibiting important proteins that recognize danger signals (either from infectious invaders or from byproducts of lupus inflammation). These proteins, which hydroxychloroquine inhibits, are called Toll-Like Receptors. When they are stimulated, the body makes a lot of a protein called type one interferon. Interferon can be very helpful if you are trying to fight off a virus, but it can cause a great deal of trouble in lupus by stimulating a vicious, self-perpetuating circle of inflammation.  By inhibiting the production of interferon just enough (but not too much) a proper balance might be found between protecting the body from lupus flares and protecting the body from viruses.

Hydroxychloroquine is probably only a weak inhibitor of Toll-Like Receptors. Some potentially stronger biologic drugs, which target the specific Toll-Like Receptors that are acting up in lupus, are currently in the early stages of being studied.

Disease Diagnosis May Be Revolutionized By IPod-sized Microscope

A pocket-sized microscope that may prove useful for diagnosing diseases like malaria in the developing world has been developed by researchers at the California Institute of Technology in Pasadena.

They say that the new powerful microscope, dubbed an optofluidic microscope, can be built onto a single image-sensing chip, and that it does not need any lenses. "Because the image processing that's needed is trivial in computing terms, we could build the microscope into an iPod-sized device with an LCD display," New Scientist magazine quoted Changhuei Yang, who led the team behind this breakthrough, as saying.

"The 10dollar chip would be a disposable, like an inkjet cartridge, and the whole thing would fit into a clinicians' back pocket," he said, adding that a disposable sensor would reduce the risk of contamination between samples.

Yang has revealed that he relied on CCD technology, which is commonly used in digital cameras, and a computer program to develop the miniaturised microscope.

So far, the new approach has allowed his team to image sub-micrometre features of algae, nematodes, and pollen.

Yang is upbeat that his device can succeed on the commercial market, suggests a research article in the journal PNAS.

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"The whole thing is truly compact--it could be put in a cell phone--and it can use just sunlight for illumination, which makes it very appealing for Third-World applications," he said.

Yang is currently in discussion with biotech companies to mass-produce the chip.

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He says that the platform into which the chip is integrated can vary depending upon the needs of the user - like health workers in rural areas could carry cheap, compact models to test individuals for malaria, and disposable versions could be carried into the battlefield.

"We could build hundreds or thousands of optofluidic microscopes onto a single chip, which would allow many organisms to be imaged and analysed at once," says Xiquan Cui, a graduate student associated with the project.

Yang envisions the incorporation of the microscope chips into devices that are implanted into the human body in the future.

"An implantable microscope analysis system can autonomously screen for and isolate rogue cancer cells in blood circulation, thus, providing important diagnostic information and helping arrest the spread of cancer," he said.

Source-ANIRAS/L

A Paper Microscope That Costs Only 50 Cents Can Detect Malaria From Just A Drop Of Blood - And It Could Revolutionize Medicine

TED Conference/Flickr

Manu Prakash with the Foldscope, a microscope made almost entirely of paper.

For a whole lot of people, especially those in developing countries, science - and with it, medicine - isn't readily available to the majority of citizens. But Manu Prakash wants to change that.

Prakash, an assistant professor of bioengineering at Stanford, is the proprietor of "frugal science," a term he coined to explain the movement toward building cheap versions of high tech tools. His endeavor aims to make medical devices both affordable and available to the masses.

The way Prakash sees it, labs don't need the most expensive equipment out there in order to reach profound breakthroughs. "Today people look at these extraordinary labs and forget that in the 1800s they could still do the exact same science," he told The New York Times.

So in 2014 he created a paper microscope, aptly named the Foldscope, that costs only 50 cents to produce.

Though microscopes might seem like a mundane piece of equipment, they remain an integral part of detecting disease and analyzing blood samples. Yet despite their necessity, they're expensive. A quality microscope can cost hundreds of dollars, plus even more to keep it maintained.

For labs in developing countries, these costs often lie outside their meager budgets. Even for labs that can afford the luxury of a high-powered microscope, properly trained technicians come at a steep price as well.

TED

The Foldscope is color-coded for easy assembly.

Prakash's Foldscope is made almost entirely of paper. It's color-coded and perforated to guide users in construction, but features no written instructions, making it universally understandable. All of the microscope's non-paper parts, such as its lens and battery, are built in to the sheet, keeping assembly as simple as possible.

The higher resolution version of the microscope magnifies up to 2,100 times and costs around $1, while the lower resolution costs around 50 cents. The entire microscope is small enough to fit in a pocket, nearly weightless, and incredibly sturdy - it can be dropped, stomped on, or doused in water and will still work.

Practically, the Foldscope can help doctors correctly diagnose deadly diseases such as malaria, schistosomiasis, and African sleeping sickness. In a TED Talk, Prakash explains that identifying these infections is as simple as adding dye to a single drop of blood. With cheap, easy-to-use microscopes, any lab technician can learn to detect malaria, potentially revolutionizing healthcare in areas where these diseases run rampant.

While the generic Foldscope serves as a one-size-fits-all microscope, Prakash and his team have also developed specialized versions, such as a malaria-centric one, that make identifying diseases even easier.

TED

The completed Foldscope fits any standard microscrope slide.

Prakash's vision of "frugal science" didn't stop at the microscope, however. He built a $5 microfluidic chemistry lab that is able to test and analyze substances, like soil or snake venom, using a hand crank in place of electricity.

Recently, Prakash also developed a computer than runs on water droplets. The droplets are suspended in a magnetic field and move certain distances as the field rotates, effectively serving as a computer clock, an essential piece of any working computer.

More than just helping combat disease, Prakash also hopes his "frugal science" movement will make science education and research accessible across the globe.

Prakash keeps an unusual map in his room to remind him of his mission. On it, Africa is almost nonexistent, India is tiny, and China's only a little larger. The map bases the size of each country on the amount of scientific research it produces, The New York Times reported. It serves as a daily reminder to Prakash of the inequality many countries face when it comes to resources and technology.

And with that kind of motivation and ingenuity, there's no telling how far Prakash and frugal science can reach.

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