Methamphetamine-induced behavioral alterations following repeated administration of methamphetamine

Repeated administration of a large dose of methamphetamine (MA) (25 mg/kg, i.p. twice daily for 4 days) to mice enhanced locomotor activity and decreased stereotyped behavior following a subsequent injection of MA. Simultaneous determinations of catecholamines revealed a depletion of brain dopamine. The moderate doses of haloperidol significantly enhanced MA-induced locomotor activity in mice. A significant enhancement of MA-induced locomotor activity was observed in the rats pretreated with 6-hydroxydopamine into the striatum, and this effect correlated negatively with the striatal dopamine level. These results suggest that hypofunction of striatal dopaminergic neuron systems induced by repeated administration of MA may be one of possible mechanisms of the enhancement of MA-induced locomotor activity due to the decrease of stereotyped behavior.     

Effect of external high-frequency oscillation on severe cardiogenic pulmonary edema

Effective gas exchange can be maintained in animals without endotracheal intubation using external high-frequency oscillation (EHFO). The aim of this study was to evaluate the effect of EHFO in patients with respiratory failure due to severe cardiogenic pulmonary edema. Seven patients were ventilated with EHFO for 2h at 60 oscillations·min⁻¹, with a cuiras pressure of 36 cmH₂O (−26 to +10) and an inspiratory to expiratory ratio of 1:1, with EHFO. Blood gas values and hemodynamic parameters were measured. Significant increases were noted in cardiac index (2.3±0.5 to 2.5±0.5 l·m⁻²;P<0.05), stroke volume index (24±7 to 28±8 ml·m⁻²;P<0.05), and arterial O₂ pressure (Pao₂) (70±4 to 95±23 mmHg;P<0.01) without a change in pulmonary artery wedge pressure at 1 h after EHFO. The respiratory rate decreased from 28±3 to 22 ±3 breaths·min⁻¹ at 5 min after the termination of EHFO (P <0.01). Arterial CO₂ pressure (Paco₂) did not, however, decrease. Increased stroke volume without a change in pulmonary artery wedge pressure (preload) suggests either improved inotropic function of the left ventricle or reduced left ventricular afterload with EHFO. The use of EHFO may be effective not only for gas exchange but also for left ventricular function in patients with severe cardiogenic pulmonary edema.     

Treatment of 46 patients with Turner's syndrome with recombinant human growth hormone (YM-17798) for three years: a multicentre study.

A total of 46 patients with Turner's syndrome were treated for three years with recombinant hGH. Nineteen patients received hGH at a weekly dosage of 0.5 IU.kg-1.week-1, while 27 received 1.0 IU.kg-1.week-1 by daily sc injection. Both treatment groups showed a statistically significant growth increase during treatment. The increase in height over three years' treatment, as expressed by SD score (SDS) for chronological age, did not differ significantly between patients treated with 0.5 IU and those with 1.0 IU hGH. Seventeen of 22 patients over the age of 14 had exceeded their expected adult height. Plasma IGF-1 levels were elevated and no remarkable advances in bone age were observed during the treatment in either treatment group. There were no other significant changes in physical or laboratory examinations. No glucose intolerance was observed. These results indicate that hGH treatment is useful for accelerating growth velocity in patients with Turner's syndrome. However, further study will be required to find the best treatment dosage.     

Interaction of flufenamic acid on ethanol metabolism in rat.

Flufenamic acid (FA) is a widely used non-steroidal anti-inflammatory drug. It is also known to be an uncoupling agent of oxidative phosphorylation in mitochondria. The interaction of FA and ethanol has been of concern in the occupational health field, since alcohol consumption is a common habit among members of the working population. Thus, we investigated the effects of FA on ethanol metabolism in the rat. In the first experiment, FA and ethanol were administered intragastrically to male Wistar rats. Ethanol and acetaldehyde were measured in blood samples collected from the tail vein by head-space gas chromatography. In the second experiment, the interaction of FA and ethanol was observed in the perfused rat liver. The following items were monitored in perfused livers from both fed and fastd rats: uptake rate of ethanol, production rate of acetaldehyde, level of reduced pyridine nucleotides, and oxygen consumption rate. In the first experiment, the rats with FA showed significantly higher concentrations of both ethanol and acetaldehyde in blood after ethanol intake than the rats without FA. In the perfused liver, FA suppressed ethanol uptake, and increased acetaldehyde concentration in the effluent. FA decreased the level of intracellular reduced pyridine nucleotides which had been elevated by ethanol. FA caused an increase in the oxygen consumption rate, which was not altered by the coexistence of ethanol. It was concluded that FA suppressed ethanol metabolism due to suppression of acetaldehyde oxidation in the liver, despite its uncoupling effect on oxidative phosphorylation in mitochondria.     

Horseshoe anomaly of the pancreas.

A 72-year-old man with recurrent pancreatitis and a horseshoe-shaped anomaly of the pancreas is described. The diagnosis was made by endoscopic retrograde cholangiopancreatography (ERCP) and computed tomography scan; laparotomy was confirmatory. The abnormal duct branched to the lower left from an enlarged Santorini's duct; a thin Wirsung's duct was joined at its distal portion to the junction of the abnormal duct. The anomaly was associated with a cystic dilatation of the common bile duct with stone and cholecystolithiasis. This anomaly is considered to be a variation of the dominant dorsal duct syndrome.     

Development of a new wound dressing with antimicrobial delivery capability

A bilaminar wound dressing composed of an outer membrane and an inner three-dimensional matrix of a fabric or a sponge may be considered to constitute an ideal structure that promotes wound healing: the outer membrane prevents body fluid loss, controls water evaporation, and protects the wound surface from bacterial invasion, and the inner matrix encourages adherence by tissue growth into the matrix. Using this concept, we developed a biosynthetic wound dressing with a drug delivery capability. This medicated wound dressing is composed of a spongy sheet of a chitosane derivative and collagen mixture that is laminated to an antimicrobial-impregnated polyurethane membrane. In this study, a gentamycin sulfate-impregnated wound dressing was prepared and evaluated. The antimicrobial efficacy of this wound dressing was examined on an agar plate seeded with Pseudomonas aeruginosa. Also, the cytotoxicity of an antimicrobial released from this wound dressing was examined in an in vitro system with cultured skin substitutes. Both in vitro tests have shown that this wound dressing is capable of suppressing bacterial growth and minimizing cellular damage. In addition, in the treatment of wounds inflicted on rats and rabbits, this wound dressing was shown to be efficacious in covering full-thickness and split-thickness skin defects. Finally, the efficacy of this wound dressing was evaluated in a nonrandomized open-label study of 31 clinical cases. In 31 cases treated with this wound dressing, good or excellent wound healing was achieved.     

Intercellular transport through a partially denuded arterial endothelial monolayer. Effect of platelets and PGI2.

Fluorescein Dextran (FD) was shown to be transported at increased rates through partially denuded endothelial monolayer. Platelet binding to the partially denuded monolayer lowered transport rates to those comparable with intact endothelium. Inhibition of transport by platelet binding was not affected by the addition of isocarbacyclin (a stable derivative of PGI2). This result suggests that adherent platelets at the partial denudation site are sufficient to suppress transport of FD.