1 July 1992

Greg Fitz – 1 July 1992 – In rat hepatocytes, basolateral Na+‐H+ exchange and Na+‐HCO3− cotransport function as acid extruders. To assess mechanisms of acid loading, intracellular pH (pHi) recovery from an alkaline load was analyzed in short‐term cultured rat hepatocyte monolayers using the pH‐sensitive dye BCECF. Electrophysiological techniques were also used to assess the role of the membrane potential (Vm). Cells were alkaline loaded by suddenly reducing external CO2 and HCO3− (from 10% and 50 mM, respectively, to 5% and 25 mM) at constant pH.

Maria Cascales, Paloma Martin‐Sanz, Alberto Alvarez, Miguel Sanchez‐Pérez, Carmen Diez Fernández, Lisardo Boscá – 1 July 1992 – Hepatocytes isolated from the liver of rats after a necrotizing dose of thioacetamide (6.6 mmol/kg) were used to study the postnecrotic process of liver regeneration. Flow cytometry analysis revealed populations of dedifferentiated hepatocytes exhibiting physical properties (size and fluorescence emission at 530 nm) similar to those found in fetal (22 days old) liver cells.

Elliott Larson – 1 July 1992

Professor Giulio Marchesini, Elisabetta Bugianesi, Giampaolo Bianchi, Andrea Fabbri, Elisabetta Marchi, Marco Zoli, Emilio Pisi – 1 July 1992 – A block in the transsulfuration pathway has previously been suggested in cirrhosis on the basis of increased fasting methionine concentrations, decreased methionine elimination and low levels of methionine end products. To date, methionine elimination has never been studied under controlled steady‐state conditions, and the relation of the severity of liver disease to impaired methionine metabolism has not been clarified.

Giuseppe Torgano, Maurizio Vecchi, Eliana Arosio, Daniela Santambrogio, Guido Ronchi, Giorgio Annoni, Maurizio Tomasini, Ettore Contessini, Roberto De Franchis – 1 July 1992 – Little is known about the distribution of IgG‐bearing cell subpopulations in normal liver and their possible changes in disease conditions. We developed an immunohistochemical method that proved suitable and accurate for the identification and characterization of IgG‐bearing cells and their subpopulations in liver specimens. The method uses specific monoclonal antibodies on serial mirror liver sections.

Alastair J. Strain – 1 July 1992 – Incubation of fetal rat hepatocytes (FRH) with transforming growth factor β1 (TGF‐β1) resulted in growth arrest and a biphasic effect on epidermal growth factor (EGF) receptor. After 2 h of exposure, EGF receptor (EGFR) was reduced by 43%. From 6 to 24 h, TGF‐β1 exposure resulted in progressive increase in EGFR up to 74% over control. The increased binding was due to increase in high affinity EGF binding sites. FRH grown in medium containing EGF exhibited down‐regulated EGFR with loss of high affinity EGF binding sites.

Yasuaki Ito, Hideyuki Hiraishi, Mahnaz Razandi, Akira Terano, Takashi Harada, Kevin J. Ivey – 1 July 1992 – Reactive oxygen metabolites have been reported to be important in the pathogenesis of ischemia/reperfusion‐induced and alcohol‐and druginduced liver injuries. We investigated the role of superoxide dismutase, cellular and extracellular, in preventing reactive oxygen metabolite–induced cytotoxicity in cultured rat hepatocytes. Cells were exposed to reactive oxygen metabolites enzymatically generated by hypoxanthine‐xanthine oxidase.

Masakatsu Uchihara, Namiki Izumi, Chifumi Sato, Fumiaki Marumo – 1 July 1992 – Endothelin is a newly discovered potent vasoconstrictor peptide. To explain the clinical significance of endothelin in patients with chronic liver diseases, we measured the plasma concentration of endothelin in patients with chronic hepatitis (n = 15), cirrhosis with ascites (n = 8) and cirrhosis without ascites (n = 12), and we compared the findings with the plasma concentration of endothelin in normal controls (n = 14).

Andrew Mason, Boris Yoffe, Christine Noonan, Mary Mearns, Carolyn Campbell, Amanda Kelley, Robert P. Perrillo – 1 July 1992 – In this study, peripheral‐blood mononuclear cells from patients with chronic hepatitis B and spontaneous or therapy‐induced disappearance of HBsAg were examined for HBV DNA. Samples were evaluated by in situ hybridization and polymerase chain reaction both before and after clearance of HBsAg.