Electron density and temperature profile diagnostics for C-2 field reversed configuration plasmas

The 9-point Thomson scattering diagnostic system for the C-2 field reversed configuration plasmas is improved and the measured electron temperature profiles are consistent with theoretical expectations. Rayleigh scattering revealed a finite line width of the ruby laser emission, which complicates density calibration. Taking advantage of the plasma wobble motion, density profile reconstruction accuracy from the 6-chord two-color CO(2)∕HeNe interferometer data is improved.

Phase I, randomized, double-blind, placebo-controlled, single-dose escalation study of the recombinant factor VIIa variant BAY 86-6150 in hemophilia

BACKGROUND

BAY 86-6150 is a new human recombinant factor VIIa variant developed for high procoagulant activity and longer action in people with hemophilia with inhibitors.

OBJECTIVES

To investigate the safety, tolerability, pharmacodynamics, pharmacokinetics and immunogenicity of BAY 86-6150 in non-bleeding hemophilia subjects.

METHODS

The study included non-bleeding men (18-65 years of age) with moderate or severe hemophilia A or B with or without inhibitors. Sixteen subjects were randomized 3 : 1 to four cohorts of escalating doses of BAY 86-6150 (6.5, 20, 50 or 90 μg kg(-1) [n = 3 per cohort]) or placebo (n = 1 per cohort); an independent data-monitoring committee reviewed previous cohort data before the next dose escalation. Blood sampling was performed predose and postdose; subjects were monitored for 50 days postdose.

RESULTS

At the tested doses, BAY 86-6150 was not associated with clinically significant adverse events or dose-limiting toxicities. BAY 86-6150 pharmacokinetics exhibited a linear dose response, with a half-life of 5-7 h. Subjects demonstrated consistent, dose-dependent thrombin generation ex vivo in platelet-poor plasma (PPP) (mean peak effect, 26-237 nm thrombin from 6.5 to 90 μg kg(-1)). Peak thrombin levels over time paralleled BAY 86-6150, with thrombin kinetics appearing to be slightly shorter; thus, circulating BAY 86-6150 retained activity. There were corresponding decreases in activated partial thromboplastin and prothrombin times. No subject developed de novo anti-BAY 86-6150 neutralizing antibodies during the 50-day follow-up.

CONCLUSIONS

In this first-in-human, multicenter, randomized, double-blind, placebo-controlled, single-dose escalation study, BAY 86-6150 was tolerated at the highest dose (90 μg kg(-1)), with no safety concerns. Safety and efficacy will be further evaluated in phase II/III studies.

Association of vitamin D and antimicrobial peptide production during late-phase allergic responses in the lung

BACKGROUND

Vitamin D may play important roles in regulating immune responses and in defence against infectious diseases by effects on both innate and adaptive immune responses. Little is known regarding activation of vitamin D within airway tissues and its relationship to inflammation and antimicrobial responses.

OBJECTIVE

The objective of this study was to investigate the activation of vitamin D within the airways and to define relationships between vitamin D metabolites and measures of inflammatory and antimicrobial responses assessed by bronchoalveolar lavage (BAL) during late-phase responses following allergen challenge of allergic subjects.

METHODS

Segmental allergen challenge was performed with saline and allergen in 16 adult allergic subjects. BAL was performed in both saline and allergen-challenged sites 20-24 h. after challenge. Following extraction from BAL fluids, levels of 25-hydroxy-vitamin D (25(OH)D) and 1,25-dihydroxy-vitamin D (1,25(OH)(2)D) were assayed by specific radioimmunoassays. The cleavage product of cathelicidin, LL-37, was assayed by ELISA. Cellular constituents and albumin were measured.

RESULTS

Levels of vitamin D metabolites were increased in concentrated BAL fluids after allergen compared to saline challenge. Levels of 1,25(OH)(2)D increased from largely undetectable to 2.5 pm (median; range: 1-29.5; P = 0.005) while 25(OH)D increased from 3.2 (0.8-6.2) to 6.2 (1.5-184.9) nm (P = 0.0006). Levels of LL-37 increased from 2.1 (1.4-4.1) to 14.5 (2.2-106.7) ng/mL BAL (P = 0.0005). Levels of LL-37, 1,25(OH)(2)D, and 25(OH)D following allergen challenge were correlated with each other (P < 0.0001), cellular changes, and levels of albumin (P < 0.001).

CONCLUSIONS AND CLINICAL RELEVANCE

Levels of vitamin D metabolites, particularly 1,25(OH)(2)D, were low within the airways and increased after allergen challenge. The increases correlated with the magnitude of inflammation and increases in cathelicidin. Normalization to albumin suggested plasma exudation as a mechanism for the increases. The findings support a role for vitamin D in allergic and innate immune responses in the lung.

Two-color CO2/HeNe laser interferometer for C-2 experiment

A six-channel two-color interferometer has been developed for plasma electron density measurements in the C-2 field reversed configuration experiment. A CO(2) laser is utilized as the main probe beams, while copropagating visible HeNe laser beams are mainly sensitive to vibration. Density measurements in C-2 plasmas have shown that this is a reliable turn-key system. The maximum residual phase noise after vibration compensation is less than ±5°, corresponding to a line integral density of 3×10(18) m(-2). The time resolution for routine operation is 2 μs.

Development of a nine spatial point, multipulse Thomson scattering diagnostic

A Thomson scattering diagnostic has been developed for the C-2 field-reversed configuration device. Based on a multipulse ruby laser, the system measures the electron temperature at nine spatial points. These points are chosen from 22 selectable positions covering r≈1-41 cm. Twin collection lenses couple the scattered photons to nine optical fiber pairs. Extra fiber lengths delay the signals from different spatial points relative to each other, allowing up to three points to be analyzed by a single polychromator. The polychromator, using compact photomultipliers as detectors, has six spectral channels covering the range of 685-725 nm and is able to estimate electron temperatures of ≈10-200 eV. The photomultiplier output signals are recorded by digital storage oscilloscopes integrated with the main MDSplus database, with temperature and error estimates generated automatically at the conclusion of each plasma discharge.

Doppler spectroscopy and D-alpha emission diagnostics for the C-2 FRC plasma

Two Doppler spectroscopy diagnostics with complementary capabilities are developed to measure the ion temperatures and velocities of FRC plasmas in the C-2 device. First, the multichord ion doppler diagnostic can simultaneously measure 15 chords of the plasma using an image intensified camera. Second, a single-chord fast-response ion Doppler diagnostic provides much higher faster time response by using a 16-channel photo-multiplier tube array. To study the neutral density of deuterium under different wall and plasma conditions, a highly sensitive eight-channel D-alpha diagnostic has been developed and calibrated for absolute radiance measurements. These spectroscopic diagnostics capabilities, combined with other plasma diagnostics, are helping to understand and improve the field reversed configuration plasmas in the C-2 device.

Phenotypic analysis of Arabidopsis mutants: heavy metal stress

INTRODUCTIONArsenic (As) is a major environmental contaminant, arising from both industrial and agricultural use, and is one of the metals given top priority for remediation by the U.S. Department of Energy on the basis of its toxicity and widespread contamination. However, many of the molecular and genetic mechanisms contributing to arsenic toxicity and detoxification remain unknown in plants. The toxicity of arsenic depends on the arsenic oxidation state. The main arsenic oxidation states are As(III) and As(V), both of which are highly toxic to plants and animals. In plants, As(III) disrupts the sulfhydryl groups of proteins and induces the production of hydrogen peroxide, which leads to membrane damage, whereas As(V) uncouples phosphorylation in mitochondria and at high levels can inhibit seed germination. As described in this protocol, resistance or sensitivity to arsenic can be easily scored by measuring germination and root bending in exposed seedlings.