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Notes: The operation of the electron cyclotron resonance (ECR) ion source Alice is described, with attention to the improved ion analysis and the new diagnostic equipment. Ion current peaks as small as tens of nA can be measured; resolving power is about 100. Routine operation is still restricted to gases, but prototypes of ovens have passed the first tests. Since currents are still rather limited (about 400 nA for 132Xe18+), a new removable plasma chamber with increased inner diameter (63 mm), made in aluminum, is under construction. Preliminary analysis of charge state distribution of xenon isotopes shows good fits with an approximately thermodynamical distribution; a sort of effective chemical potential μc is defined from fit parameters; in the particular case shown here μc≅390 eV. A decision to install a high voltage insulation transformer to allow platform operation up to Vp=350 kV was made, and an adequate location is being found, with proper wall feedthroughs in design. © 1998 American Institute of Physics.

Notes: Recent work on the hydrodynamic theory of vortex liquids in high-Tc superconductors is reviewed. Weak microscopic pinning centers are described within the flux-flow model of Bardeen and Stephen, while strong macroscopic pins set the boundary conditions for the flow. Entanglement and intervortex interactions can yield an exceptionally large intrinsic viscosity for the vortex liquid. This large viscosity allows the effect of a few strong pins to propagate over large distances and choke off the flow. As a new and experimentally relevant example of spatially inhomogeneous pinning on macroscopic scales, we consider the response of the flux liquid to an alternating current within a simple model that incorporates viscoelastic properties of the vortex liquid.

Notes: It is a known fact that in electron cyclotron resonance ion sources, plasma impurities play a role in the formation of the ion charge state distribution (CSD). Writing the balance equations for the ion densities in a matrix form allows us to calculate CSD easily for plasmas containing an arbitrary number of elements, taking into account electron ionization, radiative recombination, charge exchange between ions, and ion flowing out of the magnetic trap. Moreover, by defining two global quantities—S0 and Sc—representative of charge exchange, the stationary case can be reduced to the resolution of only one nonlinear equation for S0 and Sc. Therefore plasma equilibria even with several species of impurity ions (carbon, oxygen, hydrogen, etc.) can be easily described and solved in this model. The application to the special case of no ion flow is discussed, to study a case similar to thermodynamic equilibrium. An additional factor exp{μ˜ i4/3}, where i is the charge state, is shown to be necessary to fit the CSD. The relationship between the ionization temperature as it appears from the CSD and the electron temperature is given. © 1998 American Institute of Physics.

Notes: 1. The aim of the present study was to investigate the role of dopamine (DA) in the hypotensive and renal effects of l-arginine during extracellular fluid volume expansion (10% bodyweight).2. Animals were randomized to non-expanded and expanded groups. Both groups received different treatments: l-arginine (250 mg/kg, i.v.), NG-nitro-l-arginine methyl ester (l-NAME; 1 mg/kg, i.v.), haloperidol (3 mg/kg, i.p.) and l-arginine + haloperidol (n = 8). Mean arterial pressure (MAP), diuresis, natriuresis, kaliuresis, glomerular filtration rate, renal plasma flow (RPF) and nitrite and nitrate (NOx) excretion were determined.3. The increase in MAP induced by l-NAME was greater in expanded than in non-expanded rats (42 ± 3 vs 32 ± 3 mmHg, respectively; P 〈 0.01). Administration of haloperidol did not modify the l-arginine hypotensive effect.4. Blockade of nitric oxide synthase diminished urine flow in non-expanded (4.15 ± 0.56 vs 0.55 ± 0.11 µL/min per 100 g; P 〈 0.01) and expanded animals (24.42 ± 3.67 vs 17.85 ± 2.16 µL/min per 100 g; P 〈 0.01). Diuresis induced by l-arginine was reduced by DA blockade in both non-expanded (17.15 ± 2.11 vs 6.82 ± 0.61 µL/min per 100 g; P 〈 0.01) and expanded animals (44.26 ± 8.45 vs 25.43 ± 5.12 µL/min per 100 g; P 〈 0.01).5. Sodium excretion decreased with l-NAME treatment in non-expanded (0.22 ± 0.03 vs 0.06 ± 0.01 µEq/min per 100 g; P 〈 0.01) and expanded animals (3.72 ± 0.70 vs 1.89 ± 0.23 µEq/min per 100 g; P 〈 0.01). Natriuresis induced by l-arginine was diminished by haloperidol both in non-expanded (0.94 ± 0.13 vs 0.43 ± 0.04 µEq/min per 100 g; P 〈 0.01) and expanded rats (12.77 ± 0.05 vs 3.53 ± 0.75 µEq/min per 100 g; P 〈 0.01). Changes in kaliuresis changes seen following treatment with l-arginine, l-NAME and l-arginine + haloperidol followed a pattern similar to that observed for sodium excretion in both groups of rats.6. l-Arginine enhanced RPF in non-expanded animals (11.96 ± 0.81 vs 14.52 ± 1.05 mL/min per 100 g; P 〈 0.01). Glomerular filtration rate was increased by extracellular volume expansion (3.08 ± 0.28 vs 5.42 ± 0.46 mL/min per 100 g; P 〈 0.01).7. The increase in NOx induced by acute volume expansion (0.18 ± 0.03 vs 0.52 ± 0.08 nmol/min per 100 g; P 〈 0.01) was diminished following the administration of haloperidol (0.52 ± 0.08 vs 0.26 ± 0.06 nmol/min per 100 g; P 〈 0.01).8. Although DA does not participate in the actions of nitric oxide on vascular tone, both systems would play an important role in renal function adaptation during extracellular fluid volume expansion.

Notes: 1. The aim of the present study was to investigate the effects of L-arginine (L-Arg) on blood pressure and water and electrolyte excretion in control and extracellular fluid volume-expanded rats (10% bodyweight with 0.9% NaCl) and to determine whether diuretic treatment with furosemide (FUR) can be optimized by the administration of L-Arg in this model.2. Both groups of animals were anaesthetized, divided into groups and treated with either 7.5 mg/kg FUR, 250 mg/kg L-Arg, 1 mg/kg NG-nitro-L-arginine methyl ester (L-NAME), FUR + L-NAME or FUR + L-Arg. Mean arterial pressure (MAP), diuresis, natriuresis and kaliuresis were determined.3. Extracellular fluid volume expansion induced no changes in MAP in control and volume-expanded rats (92±6 vs 100±8 mmHg, respectively). The hypotension induced by FUR in control and volume-expanded rats (69±7 and 76±5 mmHg, respectively) was significantly (P 〈 0.01) enhanced by the administration of L-Arg (54±3 and 64±3 mmHg, respectively).4. Injection of L-NAME increased MAP and diminished diuresis, natriuresis and kaliuresis in both groups.5. Furosemide-induced water and electrolyte excretion was blunted by the administration of L-NAME.6. The combination of L-Arg + FUR increased diuresis induced by FUR alone (control rats: 29.33±1.68 vs 12.91± 0.41 μL/min per 100 g, respectively; volume-expanded rats: 248.5±25.4 vs 112,6±8.3 μL/min per 100 g, respectively; P 〈 0.01).7. The administration of the combination of L-Arg + FUR promoted a decrease in the sodium/water excretion ratio compared with the administration of FUR alone (control rats: 0.230±0.018 vs 0.45±0.03, respectively, P 〈 0.001; volume-expanded rats: 0.091±0.010 vs 0.22±0.03, respectively, P 〈 0.01).8. The potassium/water excretion rate induced by FUR alone and in the presence of L-Arg followed a pattern similar to that seen for natriuresis (control rats: 0.35±0.05 vs 0.20±0.05 μEq/min per 100 g, respectively; volume-expanded rats: 0.045±0.008 vs 0.014±0.003 μEq/min per 100 g, respectively; P 〈 0.01).9. The decrease in the electrolyte/water excretion ratio observed with FUR + L-Arg in volume-expanded rats was greater than in control animals.10. The results of the present study show that the administration of FUR with L-Arg contributes to enhanced hypotensive and diuretic effects of FUR, thus diminishing the relative electrolyte excretion in normal conditions and in extracellular fluid volume expansion.

Notes: Background Patients suffering from allergic rhinoconjunctivitis and dyspnoea during summer may exhibit these symptoms after contact with flowers or dietary products of the elderberry tree Sambucus nigra.Objective Patients with a history of summer hayfever were tested in a routine setting for sensitization to elderberry. Nine patients having allergic symptoms due to elderberry and specific sensitization were investigated in detail. We studied the responsible allergens in extracts from elderberry pollen, flowers and berries, and investigated cross-reactivity with allergens from birch, grass and mugwort.Methods Sera from patients were tested for IgE reactivity to elderberry proteins by one-dimensional (1D) and 2D electrophoresis/immunoblotting. Inhibition studies with defined allergens and elderberry-specific antibodies were used to evaluate cross-reactivity. The main elderberry allergen was purified by gel filtration and reversed-phase HPLC, and subjected to mass spectrometry. The in-gel-digested allergen was analysed by the MS/MS sequence analysis and peptide mapping. The N-terminal sequence of the predominant allergen was analysed.Results 0.6% of 3668 randomly tested patients showed positive skin prick test and/or RAST to elderberry. IgE in patients' sera detected a predominant allergen of 33.2 kDa in extracts from elderberry pollen, flowers and berries, with an isoelectric point at pH 7.0. Pre-incubation of sera with extracts from birch, mugwort or grass pollen rendered insignificant or no inhibition of IgE binding to blotted elderberry proteins. Specific mouse antisera reacted exclusively with proteins from elderberry. N-terminal sequence analysis, as well as MS/MS spectrometry of the purified elderberry allergen, indicated homology with ribosomal inactivating proteins (RIPs).Conclusion We present evidence that the elderberry plant S. nigra harbours allergenic potency. Independent methodologies argue for a significant homology of the predominant 33.2 kDa elderberry allergen with homology to RIPs. We conclude that this protein is a candidate for a major elderberry allergen with designation Sam n 1.