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In an attempt to clarify a mechanism of polymorphonuclear cell and/or macrophage infiltration in alcoholic liver disease, we investigated a novel chemotactic and activating factor generated by rat hepatocytes isolated from the chronically ethanol-fed rats. Hepatocytes and hepatic macrophages were isolated from rat liver by perfusion and digestion with collagenase and subsequently by differential centrifugation on a metrizamide gradient. Rat polymorphonuclear cells were prepared from blood by the dextran sedimentation and Hypaque-Ficoll technique. Chemotactic activity was measured as migration of polymorphonuclear cells or hepatic macrophages using a chemotactic chamber. When hepatocytes isolated from the ethanol-fed rats were cultured in vitro, chemotactic activity for rat polymorphonuclear cells and hepatic macrophages was demonstrated in the culture supernatant. Inhibitors of transcription and protein synthesis reduced generation of chemotactic factor from these hepatocytes. Chemotactic activity of the conditioned medium was reduced after trypsin (0.25%, 37 degrees C, 30 min) or heat (56 degrees C, 30 min) treatment. The chemotactic activity was eluted at molecular weights of 20-25 kDa and 40-45 kDa following Sephadex G-150 chromatography. Superoxide anion production by polymorphonuclear cells and hepatic macrophages under the stimulation of phorbolmyristate acetate was enhanced in the presence of this chemotactic factor. This chemotactic factor may contribute to the pathogenesis of alcoholic liver disease.

In an attempt to clarify a mechanism of macrophage infiltration in galactosamine-induced hepatic injury, we investigated chemotactic factor(s) generated by murine hepatocytes exposed to galactosamine. Hepatocytes, isolated from murine liver by perfusion and digestion with collagenase, were incubated with galactosamine. Conditioned medium was collected 24 h later and chemotaxis of murine spleen cells was measured by stimulation of the conditioned medium using a modified Boyden chamber. Chemotactic activity was demonstrated in the conditioned medium of hepatocytes exposed to more than 3 mM galactosamine. Chemotactic activity of the conditioned medium was not reduced after freeze-thawing, and found to be dialyzable (molecular weight < 12,000). Trypsin (0.25%, 37 degrees C, 30 min) or heat (56 degrees C, 30 min) treatment reduced chemotactic activity of the conditioned medium. Furthermore, chemotaxis of spleen cells was decreased in the presence of lipoxygenase inhibitors (azelastine, ketotifen). These results suggest that accumulation of macrophages in the liver could be mediated by chemotactic factor produced by the galactosamine-treated hepatocytes, and that this mechanism may contribute to the pathogenesis of hepatic injury induced by galactosamine.

Plasma alpha-atrial natriuretic peptide (alpha-ANP) concentrations were measured during mechanical ventilation in nine patients with acute respiratory failure (ARF) associated with sepsis. The relationships between alpha-ANP and pulmonary hemodynamic variables were examined. A total of 22 measurements of alpha-ANP and other variables were obtained. The mean plasma alpha-ANP concentration of 22 measurements was 120.1 +/- 79.8 pg/ml (normal 31.7 +/- 12.0, mean +/- SD). Plasma alpha-ANP concentrations correlated with mean pulmonary artery pressure (MPAP) (r = .703, p less than .01) and pulmonary vascular resistance (PVR) (r = .606, p less than .01), but not with other variables. These findings suggest that alpha-ANP elevation may be related to the increases in MPAP and PVR in ARF associated with sepsis.

Messenger activity of synthetic tri- and polynucleotide analogs was studied by binding of 14C-labeled aminoacyl-tRNAs to ribosomes in the presence of the analogs. Synthetic messengers used were: poly(A) analogs in which adenosine was replaced by tubercidine (I), 3-deazaadenosine (II), 1-deazaadenosine (III) and 2-methyladenosine (IV); copolymers of adenosine and aristeromycin (V); cyclic triadenylate (VI); the heptanucleotide of 6,2'-O-cyclouridine (VII); the pentanucleotide of 8,2'-S-cycloadenosine (VIIIa); A-U-G analogs in which adenosine was replaced by 8,2'-O- and S-cycloadenosine (VIII), 8,5'-O- and S-cycloadenosine (IX); 8-oxyadenosine (x); 8-bromoadenosine (XI) and formycine (XII). Among these oligo- and polynucleotides, analogs which contained nucleotides of anti conformation having appropriate bases for Watson-Crick type hydrogen bonding stimulated the binding of corresponding tRNAs to ribosomes.

The effects of intermittent positive-pressure ventilation (IPPV) with 0, 10, and 15 cm H2O of PEEP on inferior vena cava (IVC), right and left ventricular length and septal-lateral dimensions, and cardiac output were examined in 19 patients with respiratory failure using two-dimensional echocardiography. In five patients, cardiac output was also obtained by the thermodilution technique. As PEEP was increased, IVC dimensions increased during both inspiration and expiration, and the IVC collapsibility index decreased. This indicated an increase in venous stasis and decrease in venous return to the right atrium. Increasing PEEP was associated with progressive decreases in cardiac output, and length and septal-lateral dimensions of both ventricles. The decreased cardiac output during IPPV with 10 and 15 cm H2O PEEP may be due to the decreased venous return and ventricular filling. Cardiac output determined by echocardiography was correlated closely to that by the thermodilution technique.

Five AUG analogs having 8,2'-S-cycloadenosine (I), 8,5'-S-cycloadenosine (II), 8-bromoadenosine (III), 8-oxyadenosine (IV) and formycin (V) in the first position of ApUpG W were synthesized. 3'-Phosphates of I, II and V were synthesized by phosphorylation using cyanoethylphosphate and DCC. In the case of II, 2', 3'-cyclic phosphate was directly obtained. 3'-Phosphates, thus obtained, were properly protected on the 2'-OH and/or the N6-amino group and condensed with U(OBz)pGiBu(iBu)2 using DCC to give ApUpG analogs. Some properties on paper chromatography and electrophoresis, and the UV and CD spectra of these trinucleoside diphosphates are reported.

A series of 3',5'-diesters of a 2,2'-anhydro-1-(beta-D-arabinofuranosyl)cytosine salt bearing functional substituents on the ester side chains (4--16) have been synthesized. The synthesis of these diesters involved the reaction between cytidine and the corresponding acid anhydride or acid chloride in the presence of boron trifluoride etherate. Similar reaction of bis(cytidine 5'-)suberate (21) with pivaloyl chloride gave bis[2,2'-anhydro-1-(3'-O-pivaloyl-beta-D-arabinofuranosyl)cytosine 5'-]suberate dihydrochloride (22). The reaction could also be extended to a one-step synthesis of 3'-esters of 2,2'-anhydro-1-(beta-D-arabinofuranosyl)cytosine 5'-phosphate (24) from 5'-cytidylic acid. These compounds have been examined for antitumor activity against L1210 leukemia in BDF1 mice. The diesters with a long-chain carboxylic acid (4c, 7c, 12, and 24d) showed high activity when administered intraperitoneally. The compound 24d exhibited moderate activity when administered orally.