Successful Implementation of Unmanned Aircraft Use for Delivery of a Human Organ for Transplantation.

OBJECTIVE: To understand and overcome the challenges associated with moving life-urgent payloads using unmanned aircraft. BACKGROUND DATA: Organ transportation has not been substantially innovated in the last 60 years. Unmanned aircraft systems (UAS; ie, drones) have the potential to reduce system inefficiencies and improve access to transplantation. We sought to determine if UASs could successfully be integrated into the current system of organ delivery. METHODS: A multi-disciplinary team was convened to design and build an unmanned aircraft to autonomously carry a human organ. A kidney transplant recipient was enrolled to receive a drone-shipped kidney. RESULTS: A uniquely designed organ drone was built. The aircraft was flown 44 times (total of 7.38 hours). Three experimental missions were then flown in Baltimore City over 2.8 miles. For mission #1, no payload was carried. In mission #2, a payload of ice, saline, and blood tubes (3.8 kg, 8.4 lbs) was flown. In mission #3, a human kidney for transplant (4.4 kg, 9.7 lbs) was successfully flown by a UAS. The organ was transplanted into a 44-year-old female with a history of hypertensive nephrosclerosis and anuria on dialysis for 8 years. Between postoperative days (POD) 1 and 4, urine increased from 1.0 L to 3.6 L. Creatinine decreased starting on POD 3, to an inpatient nadir of 6.9 mg/dL. The patient was discharged on POD 4. CONCLUSIONS: Here, we completed the first successful delivery of a human organ using unmanned aircraft. This study brought together multidisciplinary resources to develop, build, and test the first organ drone system, through which we performed the first transplant of a drone transported kidney. These innovations could inform not just transplantation, but other areas of medicine requiring life-saving payload delivery as well.

Biomechanical and functional variation in rat sciatic nerve following cuff electrode implantation.

BACKGROUND: Nerve cuff electrodes are commonly and successfully used for stimulating peripheral nerves. On the other hand, they occasionally induce functional and morphological changes following chronic implantation, for reasons not always clear. We hypothesize that restriction of nerve mobility due to cuff implantation may alter nerve conduction. METHODS: We quantified acute changes in nerve-muscle electrophysiology, using electromyography, and nerve kinematics in anesthetized Sprague Dawley rat sciatic nerves during controlled hindlimb joint movement. We compared electrophysiological and biomechanical response in uncuffed nerves and those secured within a cuff electrode using analysis of variance (ANOVA) and regression analysis. RESULTS: Tethering resulting from cuff implantation resulted in altered nerve strain and a complex biomechanical environment during joint movement. Coincident with biomechanical changes, electromyography revealed significantly increased variability in the response of conduction latency and amplitude in cuffed, but not free, nerves following joint movement. CONCLUSION: Our findings emphasize the importance of the mechanical interface between peripheral nerves and their devices on neurophysiological performance. This work has implications for nerve device design, implantation, and prediction of long-term efficacy.

Minimally invasive therapeutic ultrasound: Ultrasound-guided ultrasound ablation in neuro-oncology.

INTRODUCTION: To improve patient outcomes (eg, reducing blood loss and infection), practitioners have gravitated toward noninvasive and minimally invasive surgeries (MIS), which demand specialized toolkits. Focused ultrasound, for example, facilitates thermal ablation from a distance, thereby reducing injury to surrounding tissue. Focused ultrasound can often be performed noninvasively; however, it is more difficult to carry out in neuro-oncological tumors, as ultrasound is dramatically attenuated while propagating through the skull. This shortcoming has prompted exploration of MIS options for intracranial placement of focused ultrasound probes, such as within the BrainPath™ (NICO Corporation, Indianapolis, IN). Herein, we present the design, development, and in vitro testing of an image-guided, focused ultrasound prototype designed for use in MIS procedures. This probe can ablate neuro-oncological lesions despite its small size. MATERIALS & METHODS: Preliminary prototypes were iteratively designed, built, and tested. The final prototype consisted of three 8-mm-diameter therapeutic elements guided by an imaging probe. Probe functionality was validated on a series of tissue-mimicking phantoms. RESULTS: Lesions were created in tissue-mimicking phantoms with average dimensions of 2.5 × 1.2 × 6.5 mm and 3.4 × 3.25 × 9.36 mm after 10- and 30-second sonification, respectively. 30 s sonification with 118 W power at 50% duty cycle generated a peak temperature of 68 °C. Each ablation was visualized in real time by the built-in imaging probe. CONCLUSION: We developed and validated an ultrasound-guided focused ultrasound probe for use in MIS procedures. The dimensional constraints of the prototype were designed to reflect those of BrainPath trocars, which are MIS tools used to create atraumatic access to deep-seated brain pathologies.

A critical review of flexible and porous SERS sensors for analytical chemistry at the point-of-sample.

For decades surface enhanced Raman spectroscopy (SERS) has been intensely investigated as a possible solution for performing analytical chemistry at the point of sample origin. Unfortunately, due to cost and usability constraints, conventional rigid SERS sensors and microfluidic SERS sensors have yet to make a significant impact outside of the realm of academics. However, the recently introduced flexible and porous paper-based SERS sensors are proving to be widely adaptable to realistic usage cases in the field. In contrast to rigid and microfluidic SERS sensors, paper SERS sensors feature (i) the potential for roll-to-roll manufacturing methods that enable low sensor cost, (ii) simple sample collection directly onto the sensor via swabbing or dipping, and (iii) equipment-free separations for sample cleanup. In this review we argue that movement to paper-based SERS sensors will finally enable point-of-sample analytical chemistry applications. In addition, we present and compare the numerous fabrication techniques for paper SERS sensors and we describe various sample collection and sample clean-up capabilities of paper SERS sensors, with a focus on how these features enable practical applications in the field. Finally, we present our expectations for the future, including emerging ideas inspired by paper SERS.

An Initial Investigation of Unmanned Aircraft Systems (UAS) and Real-Time Organ Status Measurement for Transporting Human Organs.

Organ transportation has yet to be substantially innovated. If organs could be moved by drone, instead of ill-timed commercial aircraft or expensive charter flights, lifesaving organs could be transplanted more quickly. A modified, six-rotor UAS was used to model situations relevant to organ transportation. To monitor the organ, we developed novel technologies that provided the real-time organ status using a wireless biosensor combined with an organ global positioning system. Fourteen drone organ missions were performed. Temperatures remained stable and low (2.5 °C). Pressure changes (0.37-0.86 kPa) correlated with increased altitude. Drone travel was associated with less vibration (<0.5 G) than was observed with fixed-wing flight (>2.0 G). Peak velocity was 67.6 km/h (42 m/h). Biopsies of the kidney taken prior to and after organ shipment revealed no damage resulting from drone travel. The longest flight was 3.0 miles, modeling an organ flight between two inner city hospitals. Organ transportation may be an ideal use-case for drones. With the development of faster, larger drones, long-distance drone organ shipment may result in substantially reduced cold ischemia times, subsequently improved organ quality, and thousands of lives saved.

Inkjet-Printed Paper Fluidic Devices for Onsite Detection of Antibiotics Using Surface-Enhanced Raman Spectroscopy.

Surface enhanced Raman spectroscopy (SERS) provides rapid and sensitive identification of small molecule analytes. Traditionally, fabrication of SERS devices is an expensive process that involves the use of micro- and nano-fabrication procedures. Further, acquisition of diverse sample types requires complex preparation procedures that limits SERS to lab-based applications. Recent innovations using plasmonic nanoparticles embedded in flexible paper substrates has allowed the expansion of SERS techniques to portable analytical procedures. Recently inkjet-printing has been identified as a low cost, rapid, and highly customizable method for producing paper based SERS sensors with robust performance. This chapter details the materials and procedures by which inkjet printed SERS sensors can be fabricated and applied to relevant applications. In particular, methods for utilizing the sensors for detection of antibiotics are presented.

Vertical-flow paper SERS system for therapeutic drug monitoring of flucytosine in serum.

A number of life-saving drugs require therapeutic drug monitoring (TDM) for safe and effective use. Currently, however, TDM is performed using sophisticated analytical techniques relegated to central labs, increasing the cost per test and time to answer. Here, using a novel vertical flow membrane system with inkjet-printed surface enhanced Raman sensors, along with a portable spectrometer, we demonstrate a low cost and easy to use device to quantify levels of flucytosine, an antifungal that requires TDM for effective patient care, from undiluted human serum. To our knowledge, this work represents the first report of a passive vertical flow sample cleanup method with surface enhanced Raman detection. We first investigated and optimized the parameters of the vertical flow system for the detection of flucytosine in spiked serum samples. Then, using an optimized vertical-flow system utilizing nitrocellulose membranes and a paper SERS sensor, we achieved detection of down to 10 µg mL-1 flucytosine in undiluted serum, with quantitative detection across the entire therapeutic range. This system reduces the assay time to about 15 min, far quicker than the current gold standards. We anticipate that this novel system will enable near-patient therapeutic drug monitoring, leading to the safe and effective administration of a number of life-saving drugs. Furthermore, it will spawn the development of SERS detection systems capable of separating target analytes from real-world biological matrices.

Sexual harassment in middle and high school children and effects on physical and mental health.

Sexual harassment can be physical interaction and touching, as well as, psychological, environmental, or via Internet and text messaging. An online survey in an urban clinic asked children, aged 12 to 18 years the following: demographic data, height and weight, chronic medical conditions, healthcare use, questions concerning sexual harassment-witnessed and exposure, and finally questions from the Pediatric Symptom Checklist (PSC-35). Overall, 124 of 210 (59%) of the 12- to 18-year-olds surveyed had experienced sexual harassment, with the predominance being female 69% (80/116) versus 48% (49/92) male. Participants who had experienced sexual harassment were significantly more likely to score positive for psychological impairment than those who had not experienced sexual harassment (chi-square test P < .001; odds ratio: 4.7 (95% confidence interval, 1.9-11.8). There was a borderline significant association between elevated body mass index and having experienced sexual harassment (2-sample t test P = .08). Sexual harassment has a direct correlation to psychological impairment in adolescents, especially females.