Worldwide, a stroke occurs to approximately 15 million people annually and more than 80% survive. For many people those that survive a stroke, the result can be a significant type of long-term disability. Therefore, it is key to attempt to prevent a stroke. This is not easily able to be done, as there are certain risk factors that cannot be modified. These include age, sex, and race. Fortunately, there are factors that a person can control, which may prevent stroke. An example of a controllable risk factor is obesity. Even with this information, many individuals experience challenges following strict guidelines especially when it impacts lifestyle habits. National organizations such as the American Heart Association suggest to "monitor" symptoms. This recommendation is not only vague but unobtainable, especially if there are many stroke risk factors to monitor at once. We hypothesize that: 1) there will be a change in the metabolism of microbiome, 2) the developed sensor will be able to detecting gait disturbances and cardiac rhythm disturbances, in older adults, 3) stroke survivors will describe some reservation with giving a gut sample but would be interested in both project goals if it is proven to be a biomarker for stroke.
We examined the gut microbiome metabolism and microbial virulence factor cargo of membrane vesicular nano particle to determine if this can be a potential biomarker for the early stage of stroke. Second, we develop a body area sensor for continuous monitoring of gait and cardiac rhythm disturbances, also as a way to detect early stroke, and 3) we complete qualitative interviews to learn more from stroke survivors and their views on both aforementioned aims. Regarding the topic (1), because the presence of microbiome producing trimethylamine (TMA) increases the risk for cardiovascular disease (CVD), we used Klebsiella pneumoniae as a model bacterium to produce TMA for sensor development. For the electrochemical sensor, microbial metabolism generates reductive energy, and we have found that some redox active molecules are able to shuttle electron between microbial reductive energy pool and electrode surface. We also confirmed the concentration of TMA and Choline, respectively, to prove the concept of our novel electrochemical biosensor. For (2), The tiny human pulse vibration leads to the deformation of the conformally attached ultrathin MEG and causes a magnetic field distortion, which induces an electromotive force and generates the electric signal. In this way, abnormal or irregular heartbeats can be continuously recorded. For (3), to conduct a qualitative observation with stroke patients to understand their gait characteristics, some interview were conducted.