Left untreated, malaria can progress from being mild to severe -- and potentially fatal -- in 24 hours. So researchers at the University of British Columbia developed a method to quickly and sensitively assess the progression of the mosquito-borne infectious disease, which remains a leading killer in low-income countries.
One way malaria wreaks havoc on the body is by causing excessive amounts of toxic heme, the non-protein component of hemoglobin, to accumulate in the bloodstream. Among other things, this free heme induces oxidative stress in red blood cells (RBCs), leading to their rigidification, destruction and subsequent removal from circulation -- a condition known as hemolytic anemia.
In their study, which appeared in Integrative Biology, the UBC investigators found that RBCs become increasingly rigid in direct correlation with the concentration of oxidized heme, or hemin, in the blood. Since hemin is difficult to measure directly -- it tends to insert itself into cell membranes -- monitoring changes in RBC deformability can therefore serve as a reliable alternative marker of hemin-induced oxidative stress and malaria progression.
"Because this method is mechanical, it's well suited for use in resource-poor countries, where the vast majority of malaria transmission takes place," says Kerryn Matthews, a postdoctoral fellow at UBC and the study's lead author. "Other methods of analyzing malaria severity require training or expensive equipment or chemicals that are not readily available in developing nations."
To measure RBC deformability quickly and sensitively, the UBC investigators developed the "multiplex fluidic plunger": a simple microfluidic device consisting of a parallel array of 34 funnel-shaped, micro-sized channels across which uniform, carefully controlled pressures can be simultaneously applied.
By loading the plunger with whole blood, docking an RBC at each channel and applying progressively higher pressures until the RBCs are squeezed through -- or not, if an RBC is too stiff -- one is able to determine the rigidity, or cortical tensions, of many cells at once and build an RBC deformability profile in minutes.
"The device can be easily integrated with a conventional microscope coupled with a digital camera," says Matthews. "And the accompanying software, which does all the analysis and records the pressures, is simple to use."
In addition to indicating the status of a malaria infection, RBC deformability information would be valuable in the development of antimalarial drugs, as well as in illuminating the mechanism by which RBCs are sequestered from circulation and destroyed.
Healthy RBCs are extremely flexible, capable of squeezing through spaces -- the tiniest blood vessels, for example, or the channels between cells -- that are just fractions of their original size. By rendering them less deformable, malaria parasites impair blood flow and ultimately cause organ failure and possibly death.
According to the World Health Organization, malaria killed an estimated 429,000 people and caused approximately 212 million clinical episodes in 2015. It primarily affects children and pregnant women in poor tropical and subtropical countries.
Thomas Horacek | EurekAlert!
Tuberculosis: New drug substance BTZ-043 is being tested on patients for the first time
11.12.2019 | Klinikum der Universität München
Lighting up cardiovascular problems using nanoparticles
10.12.2019 | University of Southern California
In a joint experimental and theoretical work performed at the Heidelberg Max Planck Institute for Nuclear Physics, an international team of physicists detected for the first time an orbital crossing in the highly charged ion Pr⁹⁺. Optical spectra were recorded employing an electron beam ion trap and analysed with the aid of atomic structure calculations. A proposed nHz-wide transition has been identified and its energy was determined with high precision. Theory predicts a very high sensitivity to new physics and extremely low susceptibility to external perturbations for this “clock line” making it a unique candidate for proposed precision studies.
Laser spectroscopy of neutral atoms and singly charged ions has reached astonishing precision by merit of a chain of technological advances during the past...
The ability to investigate the dynamics of single particle at the nano-scale and femtosecond level remained an unfathomed dream for years. It was not until the dawn of the 21st century that nanotechnology and femtoscience gradually merged together and the first ultrafast microscopy of individual quantum dots (QDs) and molecules was accomplished.
Ultrafast microscopy studies entirely rely on detecting nanoparticles or single molecules with luminescence techniques, which require efficient emitters to...
Graphene, a two-dimensional structure made of carbon, is a material with excellent mechanical, electronic and optical properties. However, it did not seem suitable for magnetic applications. Together with international partners, Empa researchers have now succeeded in synthesizing a unique nanographene predicted in the 1970s, which conclusively demonstrates that carbon in very specific forms has magnetic properties that could permit future spintronic applications. The results have just been published in the renowned journal Nature Nanotechnology.
Depending on the shape and orientation of their edges, graphene nanostructures (also known as nanographenes) can have very different properties – for example,...
Using a clever technique that causes unruly crystals of iron selenide to snap into alignment, Rice University physicists have drawn a detailed map that reveals...
University of Texas and MIT researchers create virtual UAVs that can predict vehicle health, enable autonomous decision-making
In the not too distant future, we can expect to see our skies filled with unmanned aerial vehicles (UAVs) delivering packages, maybe even people, from location...
03.12.2019 | Event News
15.11.2019 | Event News
15.11.2019 | Event News
11.12.2019 | Materials Sciences
11.12.2019 | Information Technology
11.12.2019 | Life Sciences