Soft wearable electronics for underwater applications are of interest, but depend on the development of a waterproof, long-term sustainable power source. In this work, we report a bionic stretchable nanogenerator for underwater energy harvesting that mimics the structure of ion channels on the cytomembrane of electrocyte in an electric eel. Combining the effects of triboelectrification caused by flowing liquid and principles of electrostatic induction, the bionic stretchable nanogenerator can harvest mechanical energy from human motion underwater and output an open-circuit voltage over 10 V. Underwater applications of a bionic stretchable nanogenerator have also been demonstrated, such as human body multi-position motion monitoring and an undersea rescue system. The advantages of excellent flexibility, stretchability, outstanding tensile fatigue resistance (over 50,000 times) and underwater performance make the bionic stretchable nanogenerator a promising sustainable power source for the soft wearable electronics used underwater.

Changes in endocardial pressure (EP) have important clinical significance for heart failure patients with impaired cardiac function. As a vital parameter for evaluating cardiac function, EP is commonly monitored by invasive and expensive cardiac catheterization, which is not feasible for long-term and continuous data collection. In this work, a miniaturized, flexible, and selfpowered endocardial pressure sensor (SEPS) based on triboelectric nanogenerator (TENG), which is integrated with a surgical catheter for minimally invasive implantation, is reported. In a porcine model, SEPS is implanted into the left ventricle and the left atrium. The SEPS has a good response both in low-and high-pressure environments. The SEPS achieves the ultrasensitivity, real-time monitoring, and mechanical stability in vivo. An excellent linearity (R 2 = 0.997) with a sensitivity of 1.195 mV mmHg −1 is obtained. Furthermore, cardiac arrhythmias such as ventricular fibrillation and ventricular premature contraction can also be detected by SEPS. The device may promote the development of miniature implantable medical sensors for monitoring and diagnosis of cardiovascular diseases.

Implantable energy harvesters (IEHs) are the crucial component for self-powered devices. By harvesting energy from organisms such as heartbeat, respiration, and chemical energy from the redox reaction of glucose, IEHs are utilized as the power source of implantable medical electronics. In this review, we summarize the IEHs and self-powered implantable medical electronics (SIMEs). The typical IEHs are nanogenerators, biofuel cells, electromagnetic generators, and transcutaneous energy harvesting devices that are based on ultrasonic or optical energy. A benefit from these technologies of energy harvesting in vivo, SIMEs emerged, including cardiac pacemakers, nerve/muscle stimulators, and physiological sensors. We provide perspectives on the challenges and potential solutions associated with IEHs and SIMEs. Beyond the energy issue, we highlight the implanted devices that show the therapeutic function in vivo.

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Highlights• Patient perceptions of the quality of their interactions with their physicians have a significant association with total diabetes-related distress. Diabetes-related distress and patient-physician interactions have a significant independent association with insulin adherence and HbA1c level.• This study delineates specific aspects of the patient-physician interaction that are linked to diabetes-related distress, insulin adherence behavior, and glycemic control. Perceived physician inattention and lack of engagement (and diabetes-related distress) directly affect insulin adherence and glycemic control.

Time to diagnosis was long in CD. Physician-related delay in diagnosing CD was associated with increased overall complications and intestinal strictures (See Video Abstract, Supplemental Digital Content 1, http://links.lww.com/IBD/B646).

The human body has an abundance of available energy from the mechanical movements of walking, jumping, and running. Many devices such as electromagnetic, piezoelectric, and triboelectric energy harvesting devices have been demonstrated to convert body mechanical energy into electricity, which can be used to power various wearable and implantable electronics. However, the complicated structure, high cost of production/maintenance, and limitation of wearing and implantation sites restrict the development and commercialization of the body energy harvesters. Here, we present a body-integrated self-powered system (BISS) that is a succinct, highly efficient, and costeffective method to scavenge energy from human motions. The biomechanical energy of the moving human body can be harvested through a piece of electrode attached to skin. The basic principle of the BISS is inspired by the comprehensive effect of triboelectrification between soles and floor and electrification of the human body. We have proven the feasibility of powering electronics using the BISS in vitro and in vivo. Our investigation of the BISS exhibits an extraordinarily simple, economical, and applicable strategy to harvest energy from human body movements, which has great potential for practical applications of self-powered wearable and implantable electronics in the future.

In this work, a nanogenerator-controlled drug delivery system (DDS) for use in cancer therapy is successfully established. A new magnet triboelectric nanogenerator (MTENG) is fabricated that can guarantee the contact and detach cycle between the two friction layers and effectively increase the TENG output, up to 70 V after implantation. Using a special structural design, without the commonly used spacer, this contacting-mode MTENG can ensure a high and consistent electricity output after encapsulation and implantation. Doxorubicin-(DOX-) loaded red blood cells (RBCs) are employed as the anti-tumor DDS in this study. After DOX loading, the RBC membranes are stable and the self-release is very slow. However, upon electric stimulation from the MTENG, the release of DOX is remarkably increased, and falls back to normal again after the stimulation. Thus a controllable DDS is established. The MTENG-controllable DDS achieves an outstanding killing of carcinomatous cells both in vitro and in vivo at a low DOX dosage. These results demonstrate a prominent therapeutic effect of the MTENGcontrolled DDS for cancer therapy, which is highly promising for application in the clinic.