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Biology subjects

Wolters, A.

Publications and source records attributed to Wolters, A..

3 recordsLinked to original sources

Remote magnetomechanical neuromodulation uncovers a novel therapeutic mechanism for alleviating Parkinsonian symptoms in freely moving mice

To overcome the limitations of invasive neuromodulation systems, we introduce a wireless magnetomechanical approach for remote, minimally invasive deep brain stimulation (DBS) without chronically implanted electrodes. This method leverages biocompatible nanoscale magnetite nanodiscs (MNDs) with ground vortex magnetisation, which undergo in-plane transitions under low-frequency alternating magnetic fields, thereby generating localised piconewton-scale torques. These torques engage endogenous mechanosensory pathways to modulate neural activity, enabling reversible stimulation without the need for genetic modifications. Calcium imaging validated the rapid neuromodulatory effects of MNDs in vitro and ex vivo, which motivated the subsequent application of magnetomechanical DBS to the subthalamic nucleus in mice. We demonstrated the remote control of motor behaviour in wild-type mice and significant restoration of motor function in a severe hemiparkinsonian model. This study established the first wireless therapeutic magnetomechanical neuromodulation platform that leverages biocompatible nanomaterials and endogenous mechanosensory ion channels, representing a promising step toward untethered, clinically translatable neurotechnology.

neuroscience↗

Biocompatible PVDF Nanofibers with Embedded Magnetite Nanodiscs Enable Wireless Magnetoelectric Neuromodulation

Wireless neuromodulation technologies aim to eliminate the need for invasive hardware and enhance tissue compatibility. Magnetoelectric (ME) materials enable magnetic field-induced electrical stimulation, offering a minimally invasive neural activation. However, conventional ME systems use rigid ceramic components with limited biocompatibility. Here, we report a flexible, predominantly organic ME platform composed of polyvinylidene fluoride (PVDF) nanofibers embedded with anisotropic magnetite nanodiscs (MNDs). These MNDs were selected for their unique ability to exert magnetic torque due to vortex magnetization, and their intrinsic magnetostrictive behaviour. The resulting ME fibers preserve the piezoelectric {beta}-phase of PVDF and exhibit magnetoelectric voltage coefficient of 1.26 Vcm-{superscript 1}Oe-{superscript 1}. We compare two magnetic activation strategies; torque-based and high-frequency magnetostriction, finding that magnetostriction more effectively triggers neuronal responses. In vitro calcium imaging reveals robust activation in primary cortical neurons cultured on ME fibers. Biocompatibility post-stimulation was confirmed on ex vivo human brain tissue, with no increased cell death. Implanted into the premotor cortex of freely moving mice, the fibers enabled wireless modulation of motor behaviour under an alternating magnetic field. This work presents the first demonstration of wireless magnetoelectric neuromodulation using soft, biocompatible fiber composites, paving the way for future bioelectronic interfaces free from rigid components and tethered systems. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=182 SRC="FIGDIR/small/660052v1_ufig1.gif" ALT="Figure 1"> View larger version (41K): org.highwire.dtl.DTLVardef@7868e7org.highwire.dtl.DTLVardef@12f32a7org.highwire.dtl.DTLVardef@1a6a7e4org.highwire.dtl.DTLVardef@5876e4_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗

Predictors of emergency department attendance following NHS 111 calls for children and young people: analysis of linked data

ObjectivesTo assess whether clinical input during calls to the NHS 111 telephone-based advice service is associated with lower rates of subsequent emergency department attendance and hospital admission.\n\nDesignAlthough NHS 111 largely employs non-clinical call handling staff to triage calls using computerised clinical decision support software, some support is available from clinical supervisors, and additionally some calls are referred to out-of-hours General Practitioners (GP). We used linked data sets to examine GP and secondary care activity following calls to NHS 111, adjusting for the patient characteristics, signs and symptoms recorded during the NHS 111 call.\n\nSettingOut-of-hours care in three areas of North West London that have an integrated approach to delivering NHS 111 and out-of-hours GP care.\n\nParticipantsNHS 111 calls for children and young people aged 15 years or under. We excluded calls that were diverted to the emergency ( 999) service or where patients were advised to go to an emergency department. This left callers who were either referred to a GP or advised to manage their health needs at home.\n\nPrimary and secondary outcome measuresThe percentage of callers attending any emergency departments, major emergency department, or minor injury unit within ten hours of the NHS 111 call, and the percentage admitted to hospital following visits to emergency departments.\n\nResultsOf the 10,356 callers, 2,898 (28.0%) were advised by NHS 111 to manage their health needs at home, with an appointment with an out-of-hours GP made for the remaining 7,458 (72.0%). 14.9% (432/2,898) of the callers who were advised by NHS 111 to manage their health needs at home attended an emergency department with ten hours, compared with 16% (1,207/7,458) of callers who had an out-of-hours appointment with an out-of-hours GP. After adjusting for patient characteristics, GP out-of-hours appointment was associated with lower rates of emergency department attendance (adjusted odds ratio, 0.86, 95% CI, 0.75-0.99),). When we subset emergency department types, a GP out-of-hours appointment was associated with lower rates of minor injury unit attendance (adjusted odds ratio, 0.32, 95% CI, 0.23 - 0.44) but not major emergency department attendance (adjusted odds ratio 1.06, 95% CI 0.90-1.24). There was no association with hospital admission. Review by an NHS 111 clinical supervisor was associated with fewer emergency department attendances (adjusted OR 0.77, 95% CI, 0.62-0.97).\n\nConclusionsClinical input during or following out-of-hours calls to NHS 111 was associated with lower rates of emergency department utilisation for children and young people, though the reduction may be concentrated in lower intensity care settings. Thus, there may be potential to reduce the use of emergency care by providing access to clinical advice or out-of-hour services in other settings through the NHS 111 telephone service.

epidemiology↗