Activation of nociceptor sensory neurons by noxious stimuli both triggers pain and increases capillary permeability and blood flow to produce neurogenic inflammation 1 , 2 , but whether nociceptors also interact with the immune system remains poorly understood. Here we report a neurotechnology for selective epineural optogenetic neuromodulation of nociceptors and demonstrate that nociceptor activation drives both protective pain behavior and inflammation. The wireless optoelectronic system consists of sub-millimeter-scale light-emitting diodes embedded in a soft, circumneural sciatic nerve implant, powered and driven by a miniaturized head-mounted control unit. Photostimulation of axons in freely moving mice that express channelrhodopsin only in nociceptors resulted in behaviors characteristic of pain, reflecting orthodromic input to the spinal cord. It also led to immune reactions in the skin in the absence of inflammation and potentiation of established inflammation, a consequence of the antidromic activation of nociceptor peripheral terminals. These results reveal a link between nociceptors and immune cells, which may have implications for the treatment of inflammation.

No abstract

No abstract

Schlüsselwörter: Schrittmacher, Stimulationselektroden, Telemetrie, intrakardiales EKG Rückschlüsse auf ischämische Veränderungen im Myokard lassen sich durch Formanalyse des telemetrisch übertragenen intrakardialen EKG nicht ziehen, da nur die Aktionspotentiale des Myokards in unmittelbarer Umgebung des Elektrodenkopfes registriert werden. Durch Amplitudenvergleich und spektrale Analyse ist es jedoch möglich, neue Elektrodenmaterialien und deren Detektionsverhalten in-vivo über einen langen Zeitraum zu überprüfen. Ebenso läßt sich eine rhythmologische Beurteilung des Patienten und die Überprüfung der Elektroden auf potentielle Defekte durchführen. Eine Einschränkung der Schrittmacherlebenszeit ist wegen des geringen Energiebedarfs auch bei täglichen Übertragungsperioden mit dem passiven induktiven Verfahren nicht gegeben. Conclusions äs to whether there are any ischemic changes in the myocardium cannot be drawn on the basic of signal analysis of the telemetrically transmitted intracardiac ECG, because only the electrical potentials of the myocardium in the immediate vicinity of the electrode are detected. A comparison of amplitudes, and spectral analysis, however, permit us to examine new electrode materials and their sensing behavior in vivo over a long period of time. The rhythmologic followup of patients and the checking of the electrodes for potential defects, can also be effected. Owing to the negligible energy consumption -even with daily transmission -there is no reduction of pacemaker life time when using the passive inductive telemetry System. Brought to you by |

This report describes an emergent balloon aortic valvuloplasty (BAV) procedure performed under cardiopulmonary resuscitation in a 79-year-old man with severe symptomatic aortic stenosis (mean gradient 78 mm Hg, valve area 0.71 cm2, and left ventricular ejection fraction 40%) awaiting surgery and who was admitted for heart failure rapidly evolving to cardiogenic shock and multiorgan failure. Decision was made to perform emergent BAV. After crossing the valve with a 6 French catheter, the patient developed an electromechanical dissociation confirmed at transesophageal echocardiography and cardiac arrest. Manual chest compressions were initiated along with the application of high doses of intravenous adrenaline, and BAV was performed under ongoing resuscitation. Despite BAV, transoesophageal echocardiography demonstrated no cardiac activity. At this point, it was decided to advance a pigtail catheter over the wire already in place in the left ventricle and to inject intracardiac adrenaline (1 mg, followed by 5 mg). Left ventricular contraction progressively resumed and, in the absence of aortic regurgitation, an intraaortic balloon pump was inserted. The patient could be weaned from intraaortic balloon pump and vasopressors on day 1, extubated on day 6, and recovered from multiorgan failure. In the absence of neurologic deficits, he underwent uneventful transcatheter aortic valve implantation on day 12 and was discharged to a cardiac rehabilitation program on day 30. At 3-month follow-up, he reported dyspnea NYHA class II as the only symptom.This case shows that severe aortic stenosis leading to electromechanical dissociation may be treated by emergent BAV and intracardiac administration of high-dose adrenaline. Intracardiac adrenaline may be considered in case of refractory electromechanical dissociation occurring in the cardiac catheterization laboratory.