Beneficial effects of acetazolamide on paroxysmal attacks of girdle sensation in multiple sclerosis

A 56-year-old woman with a 40-year history of multiple sclerosis (MS) developed paroxysmal attacks of girdle sensation in the Th5-6 dermatomes. The attacks lasted 20-60 minutes and occured up to three times per week. T2-weighted MR imaging of the spinal cord showed high intensity area from Th5 to Th8. Electrocardiography, echocardiography and laboratory findings did not indicate ischemic heart disease; therefore, the paroxysms were attributed to the spinal cord lesions. Attacks were successfully suppressed by acetazolamide 250 mg/day. Although carbamazepine is frequently used to treat paroxysmal attacks in MS, we would like to suggest that acetazolamide may also be beneficial in some patients with paroxysmal symptoms.     

Hepatorenal reflex plays an important role in natriuresis after high-NaCl food intake in conscious dogs

Responses of renal nerve activity and urinary Na+ and Cl- excretion were examined in chronically instrumented conscious dogs through feedings of boiled rice with or without NaCl. The boiled rice (20 g/kg body wt) without NaCl did not influence plasma Na+ and Cl- concentrations, renal nerve activity, or urinary Na+ excretion but decreased urinary Cl- excretion. On the other hand, boiled rice containing NaCl (0.4 g/kg body wt) increased plasma Na+ (+3.8 +/- 0.7 meq/l) and Cl- (+3.0 +/- 1.5 meq/l) concentrations, then decreased renal nerve activity by 61 +/- 4%, and increased urinary Na+ and Cl- excretions. In dogs with hepatic denervation, a decrease in renal nerve activity, which was observed in intact dogs in response to the high-NaCl food intake, was completely abolished along with significant attenuation of postprandial natriuresis. That is, only 9 +/- 5% of the loaded Na+ and 7 +/- 3% of the loaded Cl- were excreted during 4 consecutive hours in hepatic-denervated dogs, whereas 36 +/- 5% of the loaded Na+ and 36 +/- 4% of the loaded Cl- were excreted in intact dogs. In dogs with renal denervation, postprandial natriuresis was also attenuated. These results indicate that the high-NaCl food intake elicits a decrease in renal nerve activity, the decrease is predominantly mediated by the hepatic nerves, and the decrease in renal nerve activity plays an important role in augmentation of urinary Na+ and Cl- excretion. Thus, the hepatorenal reflex may play an important role in controlling extracellular fluid homeostasis during food intake.     

Local expression of C-type natriuretic peptide markedly suppresses neointimal formation in rat injured arteries through an autocrine/paracrine loop

BACKGROUND: In vivo gene transfer into injured arteries may provide a new means to facilitate molecular understanding of and to treat the intractable fibroproliferative arterial diseases. Selection of an optimal molecule to be transferred will be a key to successful gene therapy in the future. We tested the hypothesis that a secreted multifactorial molecule should act more efficiently through an autocrine/paracrine loop to suppress neointimal formation elicited in injured arteries than a simple growth-inhibiting molecule that might be expressed inside cells. METHODS AND RESULTS: We constructed an adenoviral vector (AdCACNP) expressing C-type natriuretic peptide (CNP), a secreted stimulator of membrane-bound guanyl cyclase. AdCACNP directs cells to secrete large quantities of biologically active CNP. Serum-stimulated DNA synthesis and cell proliferation were only moderately suppressed in arterial smooth muscle cells infected with AdCACNP in vitro. However, when AdCACNP was applied to balloon-injured rat carotid arteries in vivo, neointimal formation was markedly reduced (90% reduction) in an infection-site-specific manner without an increase in plasma CNP level. CONCLUSIONS: Our results showed that CNP, a secreted multifactorial molecule, was indeed effective in suppressing fibroproliferative response in injured arteries and suggest that the potent antiproliferation effect may not be the most critical factor for the effective suppression of neointimal formation. An adenovirus-mediated expression of CNP could be an effective and site-specific form of molecular intervention in proliferative arterial diseases.     

Bloch wave-based calculation of imaging properties of high-resolution scanning confocal electron microscopy

An efficient, Bloch wave-based method is presented for simulation of high-resolution scanning confocal electron microscopy (SCEM) images. The latter are predicted to have coherent nature, i.e. to exhibit atomic contrast reversals depending on the lens defocus settings and sample thickness. The optimal defocus settings are suggested and the 3D imaging capabilities of SCEM are analyzed in detail. In particular, by monitoring average image intensity as a function of the probe focus depth, it should be possible to accurately measure the depth of a heavy-atom layer embedded in a light-element matrix.     

Molecular dynamics simulation of cis-1,4-polybutadiene. 2. Chain motion and origin of the fast process

Molecular dynamics (MD) simulations of cis-1,4-polybutadiene in bulk amorphous state were performed to elucidate the origin of a fast relaxation process observed by quasielastic neutron scattering (QENS) measurements. The details of the torsional motion for each dihedral angle were investigated with the torsional auto- and cross-correlation functions for several temperatures in this study. Temperature dependence of the correlation between the torsional autocorrelation and cross-correlation functions is also evaluated. The origin of the fast process of cis-1,4-polybutadiene is found to be mainly the cooperative conformational transitions of two dihedral angles located at both sides of the CH₂-CH₂ bond when the bond is in the trans conformation. The cooperative conformational transitions exhibit even below the glass transition temperature of cis-1,4-polybutadiene. The cooperative motion appears at about 50 K below the glass transition temperature, corresponding to the Vogel-Fulcher temperature.     

Accelerated degradation testing of gas diffusion electrodes for the chlor-alkali process

The chlor-alkali industry consumes large amounts of energy. The gas diffusion cathode has been investigated for energy saving modifications. To commercialize the process, an electrode of high durability is required. Electrolytic operating factors causing electrode deterioration were examined. Under the condition of low oxygen concentration operation, the degradation of the electrode was significantly accelerated. The life of the electrode was also estimated by an acceleration test. The relationship between the logarithm of the life and the operating overvoltage was linear. Using this relation, the life of a possible mass production electrode was assumed to be five years or more.     

Interaction of hydrogen with carbon coils at low temperature

Hydrogen was adsorbed on carbon coils under 10 MPa hydrogen gas at liquid nitrogen temperature. The equilibrium pressure of hydrogen desorbed from the as-grown carbon coils with an amorphous structure was three to four times greater than those of multiwall carbon nanotubes (MWNT) and active carbons (AC). The heat treatment of the carbon coils at 850 °C contributed to an increase in hydrogen adsorption by 20% compared to the as-grown carbon coils. On the other hand, the adsorption of hydrogen gas on the carbon coils decreased significantly after heat treatment at a temperature higher than 1000 °C due to formation of capsule-like carbon composed of 10-20 layers on the surface of the carbon coils.     

Friction characteristics of inorganic or organic thin coatings on solid surfaces under water lubrication

Water has been considered as an alternative working fluid for hydraulic power systems in order to minimize the consumption of fossil fuels and mineral oils. In spite of the many advantages to this use of water, difficult technical problems remain. The key technology for establishing a water hydraulic system is tribology, because water has a lack of lubricity, and thus some coating is needed to protect the metal surfaces from corrosion and frictional wear when using water as a lubricant. It has already been demonstrated that some Si-containing materials have good lubricity in a water environment. Recently, it has been shown that diamond-like carbon (DLC) coatings also have good lubricity with water. In order to clarify the mechanism by which such materials are lubricated with water, and to develop surface coatings that have good lubricity with water, the friction characteristic of several coated metals were investigated in this study. Coatings of CrN, CrSiN, and two types of DLC were applied on an SUS630 stainless steel flat disk substrate. Additive-free distilled water was used as a lubricating fluid. The friction characteristics of these coatings at different sliding speeds were evaluated using a tribometer with two contact configurations in which stainless steel balls and a flat ring without coatings were used as mating specimens.In addition, the lubrication characteristics of organic hydro-gels such as alginic acid or its metal salt were studied by immobilizing them on the surface, and their effects on the lubrication with water were discussed.     

Application of transmission electron microscopes to nanometre-sized fabrication by means of electron beam-induced deposition

Electron beam‐induced deposition was carried out using a scanning transmission electron microscope with a field emission gun to fabricate nanometre‐sized structures. A small amount of a metal–organic gas was introduced near the substrate in the microscope chamber, and focused electron beams were irradiated. Two‐ and three‐dimensional structures were fabricated by scanning the beam position. The minimum line width of the freestanding structures was 8 nm at a constant gas flux used. This line width of 8 nm is considered to be achieved by employing a high accelerating voltage, which leads to a small probe size, and the optimum scanning speed.