Abstract: A brush for non-invasive biopsy may include a distal tip forming a cavity, where an opening of the cavity faces proximally. A shaft may be included, where the shaft is movable relative to the distal tip, where a distal end of the shaft is located within the cavity when the brush is in a first state, and where at least a portion of the distal end of the shaft is located outside the cavity when the brush is in a second state. A set of bristles may be located at the distal end of the shaft, where the bristles at least partially move from within the cavity of the distal tip to outside the cavity of the distal tip when the brush moves from the first state to the second state.

Abstract: A brush for non-invasive biopsy may include a distal tip forming a cavity, where an opening of the cavity faces proximally. A shaft may be included, where the shaft is movable relative to the distal tip, where a distal end of the shaft is located within the cavity when the brush is in a first state, and where at least a portion of the distal end of the shaft is located outside the cavity when the brush is in a second state. A set of bristles may be located at the distal end of the shaft, where the bristles at least partially move from within the cavity of the distal tip to outside the cavity of the distal tip when the brush moves from the first state to the second state.

Abstract: A brush for non-invasive biopsy may include a distal tip forming a cavity, where an opening of the cavity faces proximally. A shaft may be included, where the shaft is movable relative to the distal tip, where a distal end of the shaft is located within the cavity when the brush is in a first state, and where at least a portion of the distal end of the shaft is located outside the cavity when the brush is in a second state. A set of bristles may be located at the distal end of the shaft, where the bristles at least partially move from within the cavity of the distal tip to outside the cavity of the distal tip when the brush moves from the first state to the second state.

Abstract: The invention provides a diagnostic test for gastrointestinal disorders by providing a safe, convenient, reliable method for measuring gastric emptying. In this test, a tracer amount of 13C-glutamine or 13C-glutamic acid is added to a liquid meal, or 13C-glutamic acid added to a solid meal. After digestion in the stomach, the meal is emptied into the small bowel, where the labeled 13C-tracer is immediately taken up and metabolized by the cells lining the small bowel. The released 13CO2 is detected in the breath. The measurement of rise in the level of 13CO2 as a function of time is correlated to the rate of gastric emptying.