Sliced graphene foam films for dual-functional wearable strain sensors and switches.

The demand for wearable sensors is growing in many emerging fields, such as health monitoring, human-machine interfaces, robotics and personalized medicine. Here, we report the integration of skin-mountable, flexible, stretchable, dual-functional sensors and switches together with silicon-based electronics to create a novel healthcare system. We employ a facile approach to design highly stretchable graphene foam (GF)/PDMS composite films with tunable sensitivities and switching capabilities by simply controlling the thickness of GF. The GF/PDMS composite films deliver a high gauge factor of 24 at a 10% strain, tunable stretchability up to 70% and an excellent on/off switching ratio on the order of 1000. The highly reversible switching capability of the composite films is realized by identifying abnormal resistance changes at strains beyond a threshold value. To bridge the gap between signal transmission, wireless communication and post-processing in wearable devices, the sensors are combined with electronics, allowing data transmission to a smartphone using a custom-developed application consisting of a user-friendly interface. The novel approaches reported here offer a wide range of practical applications, including medical diagnosis, health monitoring and patient healthcare.

Lipopolysaccharide binding protein in cirrhotic patients with severe sepsis.

BACKGROUND: Lipopolysaccharide binding protein (LBP) is an acute-phase protein produced by the liver. It has been shown that LBP plays an important role in the inflammatory response to sepsis. LBP has also been shown to protect animals from endotoxin challenge by facilitating the removal of endotoxin from the blood circulation. Cirrhotic patients are susceptible to bacterial infection. It is unknown whether pre-existing liver dysfunction impacts the LBP levels and thus the prognosis in severe sepsis. METHODS: We evaluated the serum LBP, inflammatory cytokines, and the relationship between LBP concentrations, functional liver reserve and outcomes in 58 critically ill cirrhotic patients with severe sepsis. RESULTS: The serum LBP levels were significantly higher in 28-day survivors, while the interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) levels were significantly higher in non-survivors. We analyzed the receiver operating characteristic (ROC) curve to determine the cut-off point for LBP to predict 28-day mortality. The cumulative rates at 28 days were 58.3% versus 16.7% for the high LBP group (>46 ng/mL) and low LBP group (<46 ng/mL) (p < 0.001). The high-LBP group had significantly lower INR, Child-Pugh, Model for End-stage Liver Disease (MELD) scores and TNF-α level. Meanwhile, the LBP levels were inversely correlated with INR, and Child-Pugh, MELD and sequential organ failure assessment (SOFA) scores. CONCLUSION: The concentration of LBP is associated inversely with disease severity scores and outcomes in critically ill cirrhotic patients with severe sepsis.