Impaired motor cortex inhibition in patients with amyotrophic lateral sclerosis. Evidence from paired transcranial magnetic stimulation

We investigated 14 patients with amyotrophic lateral sclerosis (ALS) by paired conditioning-test transcranial magnetic stimulation to test the hypothesis that the motor cortex is hyperexcitable in ALS. Intracortical (corticocortical) inhibition was significantly less in the ALS group than in an age-matched healthy control group (85.3 +/- 27.0% versus 45.2 +/- 15.5%, respectively; p < 0.0001). In contrast, intracortical facilitation, motor threshold, and cortical silent period duration in the ALS patients were not different from the control group. We suggest that the selective abnormality of intracortical inhibition is best compatible with an impaired function of inhibitory interneuronal circuits in the motor cortex that in turn renders the corticomotoneuron hyperexcitable.     

Laparoscopic cholecystectomy and gallbladder cancer: a diagnostic and therapeutic dilemma

The correct treatment strategy of patients with unsuspected gallbladder cancer undergoing laparoscopy, and the prevention of delayed diagnosis are current issues. We report a case of late diagnosis with umbilical metastasis and poor survival. A policy of careful inspection of the gallbladder and a cautious strategy in the case of gross alteration of its external morphology seems advisable during laparoscopic cholecystectomy. Although no agreement exists concerning the best treatment in the event of delayed diagnosis, the adopted strategy is contingent on patient status, disease stage and the possibility of performing appropriate follow-up.     

Monitoring the planning quality of health promotion projects in Flanders

The levels of bacterial blood endotoxin, antiendotoxin antibodies and the overall immunity were studied in 48 females with inflammatory genital diseases complicated by pelvioperitonitis. The severest pelvioperitonitis-complicated abnormality was shown to characterized by high concentrations of endotoxin and low levels of antibodies. Endotoxinemia was found to be of diagnostic and prognostic value.     

Lens antennas for mobile broadband systems in the millimetre-waverange

An improved antenna for a wireless mobile broadband system (e.g. as realised by Bosch as a demonstrator) is proposed. By means of a shaped dielectric lens the radiation pattern of a primary antenna (e.g. a short helical structure) can be shaped to optimise the power distribution across an indoor cell. The calculated performance of lenses designed for the 30 and 60 GHz bands by using geometric optics shows good agreement with measured results     

Usefulness of gastric intramucosal pH for monitoring hemodynamic complications in critically ill children

OBJECTIVE: To assess the efficacy of gastric intramucosal pH for the evaluation of tissue perfusion and prediction of hemodynamic complications in critically ill children. DESIGN: Open prospective study without controls. SETTING: Pediatric intensive care unit (ICU) of a tertiary care university pediatric hospital. PATIENTS: Thirty critically ill children (16 boys and 14 girls), age range: 3 months-12 years. MEASUREMENTS AND RESULTS: A tonometry catheter was placed in the stomach of all patients on admission to the pediatric ICU. Simultaneous tonometry and arterial gas measurements were made on admittance and every 6-12 h throughout the study; a total of 202 measurements were made. The catheter was removed after extubation and/or when the patient was hemodynamically stable. Intramucosal pH was calculated using the Henderson-Hasselbalch equation based on the pCO2 of the tonometer and arterial bicarbonate. Intramucosal pH values between 7.30 and 7.45 were considered to be normal. The patient's condition was analyzed using the Pediatric Risk Mortality Score (PRISM). The relations between intramucosal pH and the presence of major hemodynamic complications (cardiopulmonary arrest, shock), minor hemodynamic complications (hypotension, hypovolemia or arrhythmia), death, PRISM score and the duration of the stay in the pediatric ICU were analyzed. Intramucosal pH on admission was 7.48 +/- 0.15 on average (range 7.04-7.68). Five patients (16%) had an intramucosal pH lower than 7.30 on admission; these patients did not have a higher incidence of hemodynamic complications. The 16 patients (53%) who had an intramucosal pH of less than 7.30 at some time during the course of their disease had more hemodynamic complications than the patients who did not have pH lower than 7.30 (p < 0.0001). Every case of cardiopulmonary arrest and shock was related to intramucosal pH of less than 7.30. Patients with major complications (cardiopulmonary arrest and shock) had lower intramucosal pHs than those with minor hemodynamic complications (p = 0.03); similarly, they had low intramucosal pH readings more often than those with minor complications (p = 0.0032). Intramucosal pH values less than 7.30 had a sensitivity of 90% and a specificity of 98% as a predictor of hemodynamic complications. There was no relation between intramucosal pH lower than 7.30 and either PRISM or the duration of the stay in the pediatric ICU. Patients with intramucosal pH less than 7.20 had a higher PRISM than the patients who did not have pH lower than 7.20 (p < 0.05). A patient who died during the study due to cardiopulmonary arrest had prior intramucosal pH measurements of 7.23 and 7.10, and three patients died of late complications after the end of the study. Hemodynamic complications were not detected with arterial pH. Gap pH (arterial pH-intramucosal pH) and standard pH measurements yielded the same results as gastric intramucosal pH. CONCLUSION: Intramucosal pH could provide a useful early indication of hemodynamic complications in critically ill children.     

Identification and analysis of genes from Streptomyces pristinaespiralis encoding enzymes involved in the biosynthesis of the 4-dimethylamino-L-phenylalanine precursor of pristinamycin I

Dextran has been used as a carrier molecule for the synthesis of monofunctional peptide-dextran conjugates. The immunodetection of such carrier immobilized peptides on ELISA plates was compared to that of peptides adsorbed directly to immunoplates. The main features observed with peptide-dextran conjugates were as follows: only small amounts of peptide (1-2 mg) were necessary for coupling via alpha- or epsilon-amino groups to NaIO4-activated dextran (4 mg); the coupling yield was up to 68%; an amino acid analysis of the conjugate enabled the amount of carrier immobilized peptide to be calculated; an estimated 15-17 peptides were bound per dextran molecule (MW 73,500); using a carbohydrate as carrier reduces the possibility of non-specific interactions because no hydrophobic or ionic sites and no protein-like epitopes exist on the carrier apart from the peptide ligand. It can be assumed that some peptide ligands provide the forces for an interaction with the plate surface whereas other remain free for the interaction with the antibody. Thus, the detection with monoclonal anti-peptide antibodies allowed peptide-dextran conjugates to be used at coating concentrations of 1-3 nM peptide, corresponding to 0.6-2.6 ng peptide-dextran per well. In contrast, concentrations of 150-500 nM were required for coating with peptides. The applicability of monofunctional peptide-dextran conjugates was demonstrated by investigating the titer and specificity of a polyclonal anti-peptide serum developed against human gastrointestinal glutathione peroxidase. The introduction of biotin as a second ligand of the dextran conjugate permitted its capture on streptavidin coated plates. This synthesis of bifunctional peptide-biotin-dextran conjugates opens up additional possibilities for applications.     

Measurements of interdiffusion coefficients in metallic melts at high temperature under horizontal static magnetic field

Application of a uniform magnetic field is expected to be a promising substitute for utilization of the microgravity environment from the view point of damping of convection in electrically conductive fluid. Measurements of interdiffusion coefficients in In₈₀Sn₂₀, Sn₉₅Pb₅, and Ge_97.5Si_2.5 melts were performed in a wide temperature range up to 1473 K under a uniform and horizontal static magnetic field of 1 T by utilizing the magnetohydrodynamics effect in these melts.     

High-current-density subnanosecond electron beams formed in a gas-filled diode at low pressures

The formation of electron beams in a gas diode filled with various gases at low and medium pressures under the action of nanosecond voltage pulses has been studied. It is shown that subnanosecond pulses of the beam current in helium, hydrogen, neon, nitrogen, argon, methane, sulfur hexafluoride, krypton, and xenon can be obtained both at atmospheric pressure and at a pressure of several units or dozens of Torr. In particular, a beam current density above 2 kA/cm² behind the foil at a pulse duration (FWHM) of 250 ps has been obtained in helium-filled diode. On the passage from the regime of ultrashort avalanche electron beam formation to the vacuum diode regime, the beam current pulse amplitude decreases, while both the beam pulse duration (FWHM) and the pulse front width increase.