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Cardiovascular disease continues to be one of the dominant causes of global mortality. One effective treatment is to utilize cardiovascular implantable devices (cIMDs) with multi-functional cell sensing and monitoring features that have the potential to manipulate cardiovascular hyperplasia disorders as well as provide therapy. However, batteries with a fixed capacity entail high-risk surgeries for battery-replacement, which causes health hazards and imposes significant costs to patients. This review accesses comprehensive power solutions for cIMDs, from conventional batteries to state-of-the-art energy harvesters and wireless power transfer (WPT) schemes. In particular, WPT has great potential to eliminate the percutaneous wires and overcome frequent battery removal. Here, the fundamentals, power transfer efficiency, antenna design and miniaturization, and operating frequencies in various WPT schemes are presented. Moreover, the power loss attenuation and bio-safety standard (specific absorption rate) for implants are also considered in WPT design envelope. In addition, wireless data transmission of implantable devices from external to internal milieu (and vice versa) along with different modulation and demodulation techniques are investigated. The last advanced power solutions for cIMDs in in-vivo and in vitro research are illustrated throughout. Finally, specifications and future potential of WPT systems in cIMDs are highlighted.

Cardiovascular diseases (CVDs) remain the dominant cause of mortality globally and are of an increasing trend. Generally, coronary stent placement is a pervasive treatment to combat CVDs. However, the cardiovascular stent employed as the passive expanded support in the blocked artery frequently introduce a postoperative complication called in-stent restenosis. The innovative self-reported stents integrated with biosensors can offer effective diagnosis and treatment of in-stent restenosis. In addition, the use of biotelemetry is essential in the interaction with physiological signals in the vessel's lumen, ensuring continuous monitoring of internal conditions within a vessel. This paper presents two compact dual-band microstrip antennas with encapsulation and without encapsulation that can implement power and data transmission. In particular, the 1.4 GHz Wireless Medical Telemetry Service (WMTS) band and 2.45 GHz Industrial Scientific and Medical (ISM) band have been allocated for wireless power transfer and biotelemetry, respectively. The proposed stent antennas employ meander slots on the radiating patch, which can achieve an ultra-small volume of 5 × 5 × 0.64 mm 3 . Moreover, the antenna configurations, reflection coefficient values, and surface current distribution plots are compared between the encapsulated and unencapsulated antennas.

This paper presents proof-of-principle of a miniatured low noise, low power, and high-sensitive malaria detection method based on the magnetoresistance (MR) sensor with a CMOS analog front-end (AFE) readout circuit for the detection of paramagnetic hemozoin particles. COMSOL Multiphysics® is employed for the finite-element (FEM) simulation of hemozoin particles to prove that the magnetic field generated from a multi-hemozoin particles system is within the sensing range of MR sensors. A CMOS AFE circuit is designed to convert the tiny current (approximately 60 µA) from MR sensors into a strong voltage signal able to be sampled and suppress high frequency and large amplitude noises stemming from the shift of the resultant magnetic field during the malaria diagnostic process. This CMOS AFE circuit is composed of a transimpedance amplifier (TIA) and a pair of Butterworth filters. This TIA can achieve a 98.5 dB dc gain and a 2.823 MHz bandwidth with low power consumption (375.65 µW) at a 3.3 V voltage supply and low input-referred noise (21.3857 nA/√Hz at 100 Hz). Butterworth filters can significantly reduce the high frequency and large amplitude noises caused by the unexpected shift of the magnetic field. The experimental results prove that the system provides an immediate response to samples with hemozoin particles and has the potential to achieve malaria parasite detection.

Cardiovascular diseases remain a significant global burden with 1‐in‐3 of all deaths attributable to the consequences of the disease. The main cause is blocked arteries which often remain undetected. Implantable medical devices (IMDs) such as stents and grafts are often used to reopen vessels but over time these too will re‐block. A vascular biosensor is developed that can report on cellularity and is amenable to being mounted on a stent or graft for remote reporting. Moreover, the device is designed to also receive currents that can induce a controlled form of cell death, apoptosis. A combined diagnostic and therapeutic biosensor would be transformational for the treatment of vascular diseases such as atherosclerosis and central line access. In this work, a cell sensing and cell apoptosing system based on the same interdigitated electrodes (IDEs) is developed. It is shown that the device is scalable and that by miniaturizing the IDEs, the detection sensitivity is increased. Apoptosis of vascular smooth muscle cells is monitored using continuous impedance measurements at a frequency of 10 kHz and rates of cell death are tracked using fluorescent dyes and live cell imaging.

Traditional point-of-care malaria diagnostic platforms lack sensitivity, the devices of them are bulky and expensive. To meet the demand for malaria diagnosis in malaria-endemic countries with low-resource, a cost-effective, easy-to-use, high-sensitivity and rapid diagnostic platform is needed. Here, we report the tunnel magnetoresistance (TMR) sensor to diagnose malaria by detecting the hemozoin. The hand-held device of TMR diagnostic platform consists of a cylindrical magnet, a TMR sensor, an Analog-Front-End circuit, and a microprocessor to display the results. The test result shows that this device can detect the synthetic hemozoin in labs and have the potential to be a point-of-care diagnosis.

No abstract available.

Background: The human landing catch (HLC) is the gold standard method for sampling host-seeking malaria vectors. However, the HLC is ethically questionable because it requires exposure of humans to potentially infectious mosquito bites.\ud Methods: Two exposure-free methods for sampling host-seeking mosquitoes were evaluated using electrocuting surfaces as potential replacements for HLC: (1) a previously evaluated, commercially available electrocuting grid (CA-EG) designed for killing flies, and (2) a custom-made mosquito electrocuting trap (MET) designed to kill African\ud malaria vectors. The MET and the CA-EG were evaluated relative to the HLC in a Latin Square experiment conducted in the Kilombero Valley, Tanzania. The sampling consistency of the traps across the night and at varying mosquito densities was investigated. Estimates of the proportion of mosquitoes caught indoors (Pi), proportion of human exposure\ud occurring indoors (πi), and proportion of mosquitoes caught when most people are likely to be indoors (Pfl) were compared for all traps.\ud Results: Whereas the CA-EG performed poorly ( 50 % sampling sensitivity relative to the HLC. The CA-EG had poor sampling sensitivity outdoors and inside. With further modification, the MET could provide an efficient and safer alternative to the HLC for the surveillance of mosquito vectors outdoors

Additional file 1: Figure S1. Catches in human landing catch.

Additional file 5. Number of mosquitoes collected pooled over the collection methods (Human landing catch and mosquito electrocuting trap) and displayed by species and per village over 15 months (October 2016 to December 2017). Totals include both female and male mosquitoes.

Additional file 7: Figure S6. Visualization of the second PCR products of ZIKV on agarose gels. Expected size of positive fragments: 76 bp. ZIKV+: positive control.

Additional file 3: Figure S2. Visualization of the PCR products of S7 gene on agarose gels. All samples were positive, except 920-1.

Additional file 13. Mean predicted Plasmodium falciparum infection rate in An. gambiae s.l. collected per village from October 2016 to December 2017, pooled over the trapping location and methods, with 95% CIs.

Additional file 2: Figure S1. Relationship between observed temperature (°C) and relative humidity (%). Red dots represent individual observations per hour recorded.

Additional file 1. Assembled Mosquito Electrocuting trap used for mosquito collections, connected to the power supplier and the 12-volt batteries.

Additional file 6: Figure S5. Visualization of the first PCR products of DENV 4 on agarose gels. Expected size of positive fragments: 63 bp. DENV4+: positive control.

Additional file 10: Figure S9. Visualization of the individual PCR products of DENV1, DENV2 and DENV3. Samples from Figure S8 are shown for individual runs for each of the three DENV isotypes. Expected size for DENV1 run was 71 bp, 199 bp for the DENV2 run, and 167 bp for the DENV3 run. DENV1+, DENV2+ and DENV3+: positive controls.

Additional file 2. Subsampling strategy.

Additional file 9: Figure S8. Visualization of the second PCR products of DENV 1-3 on agarose gels. Expected size of positive fragments: 63 bp. DENV1+: positive control.

Additional file 6: Figure S5. Visualization of the first PCR products of DENV 4 on agarose gels. Expected size of positive fragments: 63 bp. DENV4+: positive control.

Additional file 6. Number of An. gambiae complex females that tested positive for the presence of P. falciparum sporozoites during dry (November 2016 to March 2017 and November to December 2017) and wet season (October 2016) with different trapping methods (HLC, MET) and at different trapping locations (indoors versus outside of houses). Numbers represent totals pooled over study villages and the collection period (October 2016 to March 2017).

Additional file 1: Figure S1. Catches in human landing catch.

Additional file 13. Mean predicted Plasmodium falciparum infection rate in An. gambiae s.l. collected per village from October 2016 to December 2017, pooled over the trapping location and methods, with 95% CIs.