A promising microscopic technique for detecting Schistosoma mansoni eggs.

Schistosomiasis is one of the most devastating neglected tropical diseases, affecting over 250 million people worldwide and contributing to approximately 280,000 deaths annually. Microscopic detection of Schistosoma mansoni eggs in fecal samples using the Kato-Katz method remains the diagnostic standard. However, its speed and detection efficiency are limited.

A guide to transport-of-intensity equation (TIE) imaging for biologists.

The measurement of dry cell mass (often referred to as "protein") under the microscope can be accomplished using a quantitative phase imaging technique known as Transport of Intensity Equation (TIE) microscopy. This method requires no specialized equipment, relying instead on two slightly defocused brightfield images acquired with a standard optical microscope. The images are processed by the TIE equation to convert the gradient of intensity into phase shifts and ultimately a distribution of protein mass.

Label-Free Quantification of Protein Density in Living Cells.

Intracellular water content, W, and protein concentration, P, are essential characteristics of living cells. Healthy cells maintain them within a narrow range, but often become dehydrated under severe stress; moreover, persistent loss of water (an increase in P) can lead to apoptotic death. It is very likely that protein concentration affects cellular metabolism and signaling through macromolecular crowding (MC) effects, to which P is directly related, but much remains unknown in this area.

Delayed vacuolation in mammalian cells caused by hypotonicity and ion loss.

Prolonged exposure of mammalian cells to hypotonic environments stimulates the development of sometimes large and numerous vacuoles of unknown origin. Here, we investigate the nature and formation of these vacuoles, which we term LateVacs. Vacuolation starts after osmotic cell swelling has subsided and continues for many hours thereafter.

Measurement of protein concentration in bacteria and small organelles under a light transmission microscope.

Protein concentration (PC) is an essential characteristic of cells and organelles; it determines the extent of macromolecular crowding effects and serves as a sensitive indicator of cellular health. A simple and direct way to quantify PC is provided by brightfield-based transport-of-intensity equation (TIE) imaging combined with volume measurements. However, since TIE is based on geometric optics, its applicability to micrometer-sized particles is not clear.