Alpha-1 antichymotrypsin is involved in astrocyte injury in concert with arginine-vasopressin during the development of acute hepatic encephalopathy.

Background And Aims: We developed a bio-artificial liver (BAL) using a radial-flow bioreactor and rescued mini-pig models with lethal acute liver failure (ALF). The point of the rescue is the recovery from hepatic encephalopathy (HE). HE on ALF has sometimes resulted in brain death following brain edema with astrocyte swelling.

Decreases in brain reward function reflect nicotine- and methamphetamine-withdrawal aversion in rats.

The purpose of the present study was to investigate whether brain reward function decreases during withdrawal from nicotine and methamphetamine, and whether decreased reward function is related to aversion during withdrawal from these drugs. For that purpose, male Sprague-Dawley rats were chronically infused subcutaneously with 9 mg/kg per day nicotine, or with 6 mg/kg per day methamphetamine using osmotic minipumps. In an intracranial self-stimulation (ICSS) paradigm, chronic infusion of nicotine and methamphetamine decreased the thresholds for lateral hypothalamic ICSS, whereas their antagonists, mecamylamine and haloperidol increased the ICSS thresholds in the rats treated with nicotine and methamphetamine, respectively.

Preliminary investigation of the clinical usefulness of super-high-resolution LCDs with 9 and 15 mega-sub-pixels: observation studies with phantoms.

Our purpose in this study was to evaluate the preliminary clinical efficacy of soft-copy reading of digital mammography, for a 15-mega-sub-pixel (MsP) and a 9-MsP super-high-resolution liquid-crystal display (SHR-LCD) by use of an independent sub-pixel driving technology. We performed three kinds of phantom observation studies by six radiological technologists. Detectability of a contrast-detail phantom and simulated small objects (SSOs) resembling microcalcifications (MCLs), and shape discrimination ability of SSOs with round and square shapes, were examined and compared with a 5-MP conventional LCD (5-MP LCD).

Fictive lung ventilation in the isolated brainstem preparation of the aquatic frog, Xenopus laevis.

Aquatic pipid frogs, unlike other anurans, never show sole buccal ventilation cycle, and exhale air from the lung before aspirating air into the buccal cavity. To study the mechanism that pipid frogs lack the buccal cycle, respiratory motor activities were recorded from the isolated brainstem-spinal cord preparation of Xenopus laevis. Brainstem preparations of Xenopus exhibited the intermittent burst complex (lung bursts) similar to the lung ventilation cycle in vivo.

Spatiotemporal organization of frog respiratory neurons visualized on the ventral medullary surface.

We visualized the spatiotemporal activity of respiratory-related neurons in the frog using the isolated brainstem spinal cord preparation. We recorded optical signals from the ventral surface of the medulla using a voltage-sensitive dye, and calculated cross-correlations with the integrated respiratory activity of the trigeminal nerve. Lung burst-related depolarizing optical signals were observed bilaterally as longitudinal columns in the ventrolateral medulla between the levels of trigeminal and hypoglossal rootlets, mostly caudal to the vagal rootlet.

Chemosensitive neuronal network organization in the ventral medulla analyzed by dynamic voltage-imaging.

Central chemosensitivity is critically important to maintain homeostasis. e have successfully applied a voltage-imaging technique to medullary slice and isolated brainstem-spinal cord preparations and analyzed chemosensitive neuronal network organization in the rat ventral medulla. Our results indicate that neurons in the superficial ventral medullary chemosensitive regions and deeply located medullary respiratory neuronal network are interconnected.

Extracorporeal bioartificial liver using the radial-flow bioreactor in treatment of fatal experimental hepatic encephalopathy.

An extracorporeal bioartificial liver (BAL) that could prevent death from hepatic encephalopathy in acute hepatic insufficiency was aimed to develop. A functional human hepatocellular carcinoma cell line (FLC-4) was cultured in a radial-flow bioreactor. The function of the BAL was tested in mini-pigs with acute hepatic failure induced by alpha-amanitin and lipopolysaccharide.

Lung and buccal ventilation in the frog: uncoupling coupled oscillators.

The frog, with two distinct ventilatory acts, provides a useful model to investigate the prospective interaction of two oscillators in generating the respiratory rhythm. Building on evidence supporting the existence of separate oscillators generating buccal and lung ventilation, we have attempted to uncouple the two rhythms in the isolated brain stem preparation. Opioid preferentially inhibits the lung rhythm, suggesting an uncoupling of the lung from the buccal oscillator.

Ancient gill and lung oscillators may generate the respiratory rhythm of frogs and rats.

Though the mechanics of breathing differ fundamentally between amniotes and "lower" vertebrates, homologous rhythm generators may drive air breathing in all lunged vertebrates. In both frogs and rats, two coupled oscillators, one active during the inspiratory (I) phase and the other active during the preinspiratory (PreI) phase, have been hypothesized to generate the respiratory rhythm. We used opioids to uncouple these oscillators.