Furosemide stimulation of parathormone in humans: role of the calcium-sensing receptor and the renin-angiotensin system.

Interactions between sodium and calcium regulating systems are poorly characterized but clinically important. Parathyroid hormone (PTH) levels are increased shortly after furosemide treatment by an unknown mechanism, and this effect is blunted by the previous administration of a calcimimetic in animal studies. Here, we explored further the possible underlying mechanisms of this observation in a randomized crossover placebo-controlled study performed in 18 human males. Volunteers took either cinacalcet (60 mg) or placebo and received a 20 mg furosemide injection 3 h later. Plasma samples were collected at 15-min intervals and analyzed for intact PTH, calcium, sodium, potassium, magnesium, phosphate, plasma renin activity (PRA), and aldosterone up to 6 h after furosemide injection. Urinary electrolyte excretion was also monitored. Subjects under placebo presented a sharp increase in PTH levels after furosemide injection. In the presence of cinacalcet, PTH levels were suppressed and marginal increase of PTH was observed. No significant changes in electrolytes and urinary excretion were identified that could explain the furosemide-induced increase in PTH levels. PRA and aldosterone were stimulated by furosemide injection but were not affected by previous cinacalcet ingestion. Expression of NKCC1, but not NKCC2, was found in parathyroid tissue. In conclusion, our results indicate that furosemide acutely stimulates PTH secretion in the absence of any detectable electrolyte changes in healthy adults. A possible direct effect of furosemide on parathyroid gland needs further studies

Effects of Commercial Harvest on Shovelnose Sturgeon Populations in the Upper Mississippi River

Shovelnose sturgeon Scaphirhynchus platorynchus have become an increasingly important commercial species in the upper Mississippi River (UMR) because of the collapse of foreign sturgeon (family Acipenseridae) populations and bans on imported caviar. In response to concerns about the sustainability of the commercial shovelnose sturgeon fishery in the UMR, we undertook this study to describe the demographics of the shovelnose sturgeon population and evaluate the influence of commercial harvest on shovelnose sturgeon populations in the UMR. A total of 1,682 shovelnose sturgeon were collected from eight study pools in 2006 and 2007 (Pools 4, 7, 9, 11, 13, 14, 16, and 18). Shovelnose sturgeon from upstream pools generally had greater lengths, weights, and ages than those from downstream pools. Additionally, mortality estimates were lower in upstream pools (Pools 4, 7, 9, and 11) than in downstream pools (Pools 13, 14, 16, and 18). Linear regression suggested that the slower growth of shovelnose sturgeon is a consequence of commercial harvest in the UMR. Modeling of potential management scenarios suggested that a 685-mm minimum length limit is necessary to prevent growth and recruitment overfishing of shovelnose sturgeon in the UMR

Clinical benefits of an adherence monitoring program in the management of secondary hyperparathyroidism with cinacalcet: results of a prospective randomized controlled study.

BACKGROUND/AIMS: One of the causes of uncontrolled secondary hyperparathyroidism (sHPT) is patient's poor drug adherence. We evaluated the clinical benefits of an integrated care approach on the control of sHPT by cinacalcet. METHODS: Prospective, randomized, controlled, multicenter, open-label study. Fifty hemodialysis patients on a stable dose of cinacalcet were randomized to an integrated care approach (IC) or usual care approach (UC). In the IC group, cinacalcet adherence was monitored using an electronic system. Results were discussed with the patients in motivational interviews, and drug prescription adapted accordingly. In the UC group, drug adherence was monitored, but results were not available. RESULTS: At six months, 84% of patients in the IC group achieved recommended iPTH targets versus 55% in the UC group (P = 0.04). The mean cinacalcet taking adherence improved by 10.8% in the IC group and declined by 5.3% in the UC group (P = 0.02). Concomitantly, the mean dose of cinacalcet was reduced by 7.2 mg/day in the IC group and increased by 6.4 mg/day in the UC group (P = 0.03). CONCLUSIONS: The use of a drug adherence monitoring program in the management of sHPT in hemodialysis patients receiving cinacalcet improves drug adherence and iPTH control and allows a reduction in the dose of cinacalcet

A medium size NEMP radiation system used in a shielded room

A bounded wave transmission line ENP simulator which achieves a very good confinement of the field inside its volume is described. Results of field mapping in free space and inside a shielded room are presented. These measurements have shown that the field decays very rapidly outside the structure, making it possible to use the antenna without disturbing its environment. It was also shown that when the simulator is used inside a Faraday cage, the reflections from the walls of the room do not produce significant field distortions within the working volum

Indoor radiated emission associated with power line communication systems

Experimental data characterizing indoor electric and magnetic fields radiated by power line communication (PLC) systems and used for the calculation of a local transfer function (coupling factor) are presented. It is shown that the indirect determination of electric field using magnetic field measurements and assuming a plane wave approximation may result in an underestimation of the electric field. Additionally, it is shown that the radiated field magnitudes vary significantly as a function of the position of the observation point and of the network load. A first evaluation of the indoor electromagnetic field radiated by PLC systems using NEC2 is presented and compared with experimental data

SEMIRAMIS: an asymmetrical bounded wave EMP simulator with a good confinement inside the transmission line

A transmission-line type of EMP simulator, consisting of two conductors with a central parallel plate region has been designed, fabricated and tested. It has been named SEMIRAMIS-I, which stands for Simulateur Electromagnetique a Impulsion Raide pour des Mesures Industrielles et Scientifiques. This simulator can be energized by either a CW or a transient pulse source. Testing was performed with ELGAL's EM-103 pulser (20 kV-100 kV, 7-9 ns risetime, 150 ns FWHM). The desired working volume is about 3 m long×1 m wide×1 m high. The initial design has been experimentally optimized. Measurements have been made of the simulated electromagnetic environmen

In situ control of HV cables during commissioning test operation or preventive maintenance using partial discharge reflectometry

In order to achieve control of HV cables after repair or preventive maintenance measurements should be performed on the installed cables. The authors present numerical studies on the wave reflection in the cable using the EM transients program. They show the present promises and limits of the method of partial discharge reflectometr