Search results for "Sympathetic"

DMPP and the adrenergic nerve terminal: mechanisms of noradrenaline release from vesicular and extravesicular compartments.

1977

DMPP (1,1-dimethyl-4-phenylpiperazine) in various concentrations between 1.6×10−6 M and 6.2×10−5 M was infused into isolated rabbit hearts to study the neuronal release and uptake of noradrenaline.

Die Aufnahme von ?-Methylnoradrenalin in das isolierte Kaninchenherz und seine Freisetzung durch Reserpin und Guanethidin in vivo

1965

Die Noradrenalin-Abgabe aus dem isolierten Kaninchenherzen bei sympathischer Nervenreizung und ihre pharmakologische Beeinflussung

1962

Preparing single ultra-cold antihydrogen atoms for free-fall in GBAR

2014

We discuss an experimental approach allowing to prepare antihydrogen atoms for the GBAR experiment. We study the feasibility of all necessary experimental steps: The capture of incoming $\bar{\rm H}^{+}$ ions at keV energies in a deep linear RF trap, sympathetic cooling by laser cooled Be+ ions, transfer to a miniaturized trap and Raman sideband cooling of an ion pair to the motional ground state, and further reducing the momentum of the wavepacket by adiabatic opening of the trap. For each step, we point out the experimental challenges and discuss the efficiency and characteristic times, showing that capture and cooling are possible within a few seconds. We discuss an experimental approach…

A novel cooling scheme for antiprotons

2006

We propose a novel technique which uses laser-cooled negative osmium ions for sympathetic cooling of antiprotons. Temperatures down to the sub-millikelvin range might be achievable. These antiprotons could be used to form antihydrogen at ultra-cold temperatures, thus allowing efficient magnetic trapping of antihydrogen for high-resolution laser spectroscopy. Antihydrogen at sub-millikelvin temperatures might also enable first direct measurements of the gravitational acceleration of antimatter. Currently, no other technique exists which allows the cooling of large numbers of antiprotons to temperatures below that of the surrounding trap.

Trapping and sympathetic cooling of single thorium ions for spectroscopy

2018

Precision optical spectroscopy of exotic ions reveals accurate information about nuclear properties such as charge radii and magnetic and quadrupole moments. Thorium ions exhibit unique nuclear properties with high relevance for testing symmetries of nature. We report loading and trapping of single $^{232}$Th$^+$ ions in a linear Paul trap, embedded into and sympathetically cooled by small crystals of trapped $^{40}$Ca$^+$ ions. Trapped Th ions are identified in a non-destructive manner from the voids in the laser-induced Ca fluorescence pattern emitted by the crystal, and alternatively, by means of a time-of-flight signal when extracting ions from the Paul trap and steering them into an ex…

Laser cooling of externally produced Mg ions in a Penning trap for sympathetic cooling of highly charged ions

2012

We have performed laser cooling of Mg ions confined in a Penning trap. The externally produced ions were captured in flight, stored and laser cooled. Laser-induced fluorescence was observed perpendicular to the cooling laser axis. Optical detection down to the single ion level together with electronic detection of the ion oscillations inside the Penning trap have been used to acquire information on the ion storage time, ion number and ion temperature. Evidence for formation of ion crystals has been observed. These investigations are an important prerequisite for sympathetic cooling of simultaneously stored highly-charged ions and precision laser spectroscopy of forbidden transitions in thes…

Alternative mechanisms for tiotropium

2009

Tiotropium is commonly used in the treatment of chronic obstructive pulmonary disease. Although largely considered to be a long-acting bronchodilator, its demonstrated efficacy in reducing the frequency of exacerbations and preliminary evidence from early studies indicating that it might slow the rate of decline in lung function suggested mechanisms of action in addition to simple bronchodilation. This hypothesis was examined in the recently published UPLIFT study and, although spirometric and other clinical benefits of tiotropium treatment extended to four years, the rate of decline in lung function did not appear to be reduced by the addition of tiotropium in this study. This article summ…

The effects of the tricyclic antidepressants desipramine, doxepin and iprindole on the isolated perfused rabbit heart.

1974

1. The right sympathetic nerves of isolated perfused rabbit hearts were stimulated electrically (1 msec, supramaximal strength, 15 sec) with increasing frequencies (0.25–20 Hz) at 3 min intervals before and 20 min after starting perfusion with desipramine, doxepin or iprindole. Ventricular rate, right atrial and right ventricular tensions were recorded using the transverse method. 2. Sympathic nerve stimulation caused ventricular arrhythmias in the presence of desipramine (3.3 and 5.0 · 10−6 M) and doxepin (1.6−4.7×10−6 M) but failed to produce arrhythmias in hearts not exposed to drugs, or after iprindole, cocaine and atropine. 3. When desipramine or doxepin was added to Tyrode solution co…

Imbalance between sympathetic and sensory innervation in peritoneal endometriosis

2011

To investigate possible mechanisms of pain pathophysiology in patients with peritoneal endometriosis, a clinical study on sensory and sympathetic nerve fibre sprouting in endometriosis was performed. Peritoneal lesions (n= 40) and healthy peritoneum (n= 12) were immunostained and analysed with anti-protein gene product 9.5 (PGP 9.5), anti-substance P (SP) and anti-tyrosine hydroxylase (TH), specific markers for intact nerve fibres, sensory nerve fibres and sympathetic nerve fibres, respectively, to identify the ratio of sympathetic and sensory nerve fibres. In addition, immune cell infiltrates in peritoneal endometriotic lesions were analysed and the nerve growth factor (NGF) and interleuki…