Effects of calyculin A and FK506 on the O2- generation of rat peritoneal macrophages

To investigate the role of phosphatase in O2- generation, the effects of the potent phosphoprotein phosphatase inhibitors, Calyculin A and FK506, were analyzed during phagocytosis using rat peritoneal macrophages. O2- generation was continuously measured after addition of opsonized zymosan (op. ZY) or IgG-coated zymosan (IgG-ZY). The rate of O2- generation was directly proportional to the number of macrophages, up to 1-2 x 10(6) cells/ml. It was found that the rate and duration of O2- generation were markedly inhibited by Calyculin A. The addition of 100 nM of Calyculin A reduced O2- generation to about one-tenth of the control value. In contrast, FK506 did not inhibit O2- generation, suggesting that calcium calmodulin phosphatase is not involved in the activation of NADPH oxidase. This result indicates that the process of dephosphorylation might involve activation of NADPH oxidase as a control mechanism in phagocytosis by rat peritoneal macrophages. Furthermore, since Calyculin A is an inhibitor of phosphatase 1 and 2A, it is suggested that dephosphorylation may be evoked by these phosphatases.

[Endobronchial treatments made possible by extracorporeal lung assist in a patient in status asthmaticus refractory to mechanical ventilation]

A 19-year-old endotracheally intubated women was admitted to our hospital in severe status asthmaticus that was not relieved by inhalation of beta 2-agonists or by epinephrine, aminophylline, or corticosteroids. A chest radiography revealed pneumomediastinum and subcutaneous emphysema. Pressure-limited mechanical ventilation at a peak airway pressure of 20--30 cmH2O failed to ventilate the lungs, and caused a left pneumothorax and atelectasis. Extracorporeal lung assist (ECLA) was begun and enabled repeated suctioning through a fiberoptic bronchoscope for more than a minute with no serious complications. During ECLA aerosol therapy with a large dose of a beta 2-agonist (procatherol 0.15 mg) increased the tidal volume with no adverse effects. Atelectatic areas of the lungs re-expanded, pulmonary function improved, and ECLA was stopped 86 hours after it had been started. We suggest that, although it is highly invasive, ECLA can be useful in patients with status asthmaticus refractory to mechanical ventilation, and can allow endobronchial suctioning to be done safely.

Effects of competitive blood flow on arterial graft patency and diameter. Medium-term postoperative follow-up

To identify predictors of arterial graft patency, we followed up 30 internal thoracic arterial grafts and 23 right gastroepiploic arterial grafts in situ with patency documented during postoperative angiography. After 24 months of follow-up on average, repeat angiography detected that one internal thoracic artery and two gastroepiploic arteries were anatomically occluded and that the other three gastroepiploic arteries were nonfunctioning. The logistic regression model identified a relationship between graft patency and competitive flow, which was detected as stenosis in the recipient coronary arteries (coefficients, p < 0.05; model, Hosmer-Lemeshow chi2 statistic 3.59, p = 0.89). The linear regression model demonstrated that changes in graft luminal diameter correlated with competitive flow (p < 0.01), smoking history (p < 0.05), and type of arterial grafts (p < 0.001) (R2 = 0.40, adjusted R2 = 0.36). The findings suggest a temporal relationship between competitive flow and prognosis of arterial graft.

Effects of hyaluronan on cell proliferation and proteoglycan synthesis in rabbit ligamental cells

The effect of hyaluronan (HA) on cell proliferation and synthesis of proteoglycan (PG) in rabbit ligamental cells was examined in vitro. HA promoted the incorporation of 35S-sulfate in a concentration-dependent manner, significantly at 100 micrograms/ml and upward, without effect on cell proliferation. The chromatographic profile of the 35S-labelled materials extracted with 4 M guanidine hydrochloride by Sepharose CL-2B was different in the HA-treated cells as compared with untreated cells. Although the radioactivities of the low-molecular fraction peaked at Kav 0.71 did not change, those of the high-molecular fraction (Kav 0.30-0.50) increased with treatment of HA. Ligamental cells expressed the mRNA of the PG family's versican and aggrecan (large-molecular weight PGs), biglycan and decorin (small-molecular weight PGs) in dot blot analysis. Although the mRNA expression of aggrecan, biglycan and decorin did not change, that of versican increased upon treatment with HA. These findings suggest that HA is involved in promoting production of the large-molecular-weight PG versican, and in facilitating extracellular matrix formation.

Vascular smooth muscle relaxation by alpha-adrenoceptor blocking action of dobutamine in isolated rabbit aorta

We investigated the mechanism of vascular relaxation produced by dobutamine, a positive inotropic agent with beta 1-adrenergic action. Dobutamine concentration-dependently (10 nM-10 microM) relaxed ring segments of rabbit aorta partially precontracted with 1 microM phenylephrine (PE) but did not relax those precontracted with 40 mM K+ or 5 microM prostaglandin F2 alpha (PGF2 alpha). The relaxation was not completely inhibited by pretreatment with 10 microM propranolol. Dobutamine did not significantly increase tissue cyclic AMP levels concomitantly with relaxation as does isoproterenol (ISO) in rabbit aorta. Dobutamine produced a parallel rightward shift in concentration-response curves to PE. The Schild plot analysis resulted in a linear regression of a slope of 1.077 +/- 0.077, which was not significantly different from unity. The pA2 value of dobutamine as compared with PE in rabbit aorta was 6.81 +/- 0.03. Dobutamine causes arterial dilatation mediated not only through a beta-adrenergic action but also through an alpha-adrenergic blocking action in rabbit aorta.

Biochemical profile of YM992, a novel selective serotonin reuptake inhibitor with 5-HT2A receptor antagonistic activity

YM992, (S)-2-[[(7-fluoro-4-indanyl)oxy]methyl]morpholine monohydrochloride, exhibited the biochemical profile of a selective serotonin (5-HT) reuptake inhibitor (SSRI) with 5-HT2A receptor antagonistic activity. YM922 showed the same high affinity as fluoxetine against the 5-HT reuptake site (Ki = 21 nM) and a similar affinity to that of crazodone against the 5-HT2A receptor (Ki = 86 nM). In other receptor binding studies, an affinity for the adrenergic alpha 1 receptor (Ki = 200 nM) and 5-HT2C receptor (Ki = 680 nM) was observed. In a monoamine uptake study, YM992 showed a selective 5-HT uptake inhibition (IC50 = 0.15 microM), but only very weakly inhibited both noradrenaline (NA) and dopamine (DA) uptake (IC50 = 3.1 microM (NA), > 10 microM (DA)). YM992 was also found to potently inhibit the aggregation of human platelets (IC50 = 1.9 microM), revealing antagonistic activity for the 5-HT2A receptor in vitro. Enhanced serotonergic neurotransmission, in particular that mediated by the 5-HT1A receptor, has recently been reported to be important in the long-term treatment of depressive disorders with antidepressants. In addition, some 5-HT1A receptor-mediated responses are known to be potentiated by co-administration of 5-HT2A receptor antagonists. Thus, YM992, having both selective 5-HT reuptake inhibition and 5-HT2A antagonistic activity, might show potent therapeutic activity as a novel antidepressant in comparison with conventional SSRIs.

[Depression of cellular immunity after aortic arch replacement]

Multiple organ failure due to infection is now one of the most serious postoperative complications following aortic arch replacement. We therefore evaluated the postoperative changes of cellular immunity using four parameters, 1) peripheral lymphocyte subsets 2) mitogen responsiveness 3) the activity of natural killer (NK) cells 4) interleukin-2 (IL-2) production. Patients were divided into two groups: group A (n = 5) with aortic arch replacement and group B (n = 10) with coronary artery bypass grafting. All variables were measured the day before, the day after, 3 days after, 7 days after, and 14 days after surgery. CD3 positive cells in group A were significantly lower than in group B throughout the postoperative course. CD4 positive cells in group A were significantly lower than in group B on the day after 3 days after the operation. IL-2 production in group A was markedly depressed the day after (all patients 0.8 U) and 3 days after (1.5 +/- 1.6 U) as compared to the preoperative level (7.7 +/- 4.4 U) and the levels on the same days in group B. The activity of NK cells in group A was significantly impaired the day after (10.6 +/- 6.7%) and 3 days after (10.0 +/- 6.7%) as compared to the preoperative level (28.6 +/- 16.7%) and the levels on the same days in group B. IL-2 production in group A was significantly correlated to CD3 and CD4 positive lymphocyte levels. These results clearly showed that patients who underwent aortic arch surgery suffered functional depression of cellular immunity, in particular IL-2 production and the activity of NK cells. These depressions may be a result of massive blood transfusion, tissue trauma under hypothermic cardiopulmonary bypass.

Release of spectrin-containing vesicles from human erythrocyte ghosts by dimyristoylphosphatidylcholine

Membrane vesicles, which were released from human erythrocyte ghosts by dimyristoylphosphatidylcholine (DMPC), showed a protein composition similar to that of the erythrocyte membrane, despite a reduction of in spectrin content. The spectrin content of vesicles decreased with increasing hemoglobin concentration within ghost membranes, but increased upon exposure of hemoglobin-free ghosts to a pressure of 100 MPa. The ESR spectra of spin-labeled membrane proteins showed that membrane proteins in ghosts became unfolded at high pressure. Furthermore, spectrin-poor and protein 4.1-rich vesicles were released by DMPC from diamide-treated ghosts in which spectrin was cross-linked and stabilized. Taking into account that the spectrin tetramer is stabilized by hemoglobin [Liu and Palek (1984) J. Biol. Chem. 259, 11556-11562], these results suggest that the spectrin content of DMPC-induced vesicles from erythrocyte ghosts increases with increasing instability of the cytoskeletal network in parent cells.

[Selenium concentration in blood and Duchenne-type progressive muscular dystrophy]

The concentration of selenium (Se) and the activity of glutathione peroxidase (GSH-Px) in plasma and erythrocytes were measured in healthy men and in patients with Duchenne-type progressive muscular dystrophy (DMD). In healthy men, the Se concentration in erythrocytes showed a steep rise with aging and ascended gradually in plasma. The GSH-Px activity in both plasma and erythrocytes clearly increased with aging. The relationship between the Se concentration and the GSH-Px activity in healthy men showed a parallel rise with aging, but the coefficients of correlation were not very high (r = 0.44 and 0.56 in plasma and erythrocytes, respectively. In DMD patients, on the other hand, the Se concentration in erythrocytes decreased steeply with aging, and it decreased gradually in plasma. The GSH-Px activity in both plasma and erythrocytes apparently increased as in healthy men with aging, but the level was about 80% of that of healthy men. When selenite (Se+4) is added to the whole blood in vitro at 25 degrees C, it is rapidly taken up by erythrocytes (within several minutes) and is then released into plasma (a period of 30 min), then subsequent reuptake by erythrocytes is proceeded slowly. Our attention was attracted to the pattern of selenite release from erythrocytes of DMD patients.

Renal cell carcinoma in a patient with Beckwith-Wiedemann syndrome

We report the case of a patient with Beckwith-Wiedemann syndrome (BWS) who developed renal cell carcinoma (RCC). At birth, this patient presented with macroglossia, diastasis recti, mild gigantism, hepatomegaly and hypoglycemia, and the diagnosis of BWS was made. At 22 months, an intrapelvic rhabdomyosarcoma was detected and resected. At 37 months, computed tomography (CT) demonstrated a small mass with high attenuation in the right kidney, which was surgically confirmed to be RCC.

Multiple primary cancers with microsatellite instability: report of a case

We report here a patient who developed a variety of tumors both synchronously and metachronously over a 2-year period. The involved organs were the uterus, ureter, and small and large intestines. The patient underwent open surgery 3 times and polypectomies 6 times. Postoperative histopathologic analysis showed 2 adenomas and 8 carcinomas. Genetic analysis revealed microsatellite instabilities at the tested loci in all 10 tumors, indicating that replication errors played an essential role in the tumorigenesis. Early identification of microsatellite instability could be useful for predicting development of additional primary cancers.

Taurine reduces experimental liver injury after cold ischemic preservation and a period of rewarming prior to reperfusion

Livers of male Wistar rats (250-300 g) were isolated and flushed with 10 ml of Ringer's solution and 10 ml of UW preservation solution. Then the organs were stored for 24 h at 4 degrees C in UW solution. Livers of Group 1 were rinsed with 10 ml of Ringer's solution and reperfused after hypothermic storage with oxygenated Krebs-Henseleit solution (95% O2; 5% CO2) in a nonrecirculating system at constant pressure (10 mmHg) and 37 degrees C. Livers of Group 2 were incubated for 30 min at 37 degrees C prior to reperfusion, in order to simulate rewarming of the organ upon surgical implantation. Livers of Group 3 were treated like Group 2, but taurine was admixed to the UW solution (1 mM). Livers of Group 1 showed little signs of a preservation/reperfusion injury, with low enzyme activities of the parenchymal ALT and endothelial purine nucleoside phosphorylase (PNP) in the postischemic rinse solution (ALT: 19.9 +/- 12.4; PNP: 3.3 +/- 0.4 U/liter), adequate portal flow values about 3 ml/g/min and high O2 uptake at the end of the experiment (VO2: 3.2 +/- 0.4 ml/100g/min). Livers of Group 2 exhibited nearly tenfold higher enzyme activities in the rinse solution (ALT: 247.0 +/- 94.7*; PNP: 29.5 +/- 17.0* U/l) and disturbed tissue perfusion with significantly reduced flow values of about 2 ml/g/min during the first 10 min of reperfusion. As a result, the recovery of O2 uptake was only 2.2 +/- 0.3 ml/100 g/min*. Addition of taurine (Group 3) resulted in a significant reduction of the enzyme loss (ALT: 96.2 +/- 50.0#; PNP:12.4 +/- 7.0# U/liter) and improved portal flow values and O2 uptake at the end of reperfusion (2.7 +/- 0.3 ml/100 g/min#). The results give evidence for the importance of the rewarming period after hypothermic storage, which is inevitable during implantation of the organ in vivo. Taurine seems to exert a protective effect, affecting both the vascular endothelium and parenchymal tissue (*p < 0.05 vs Group 1; # p < 0.05 vs Group 2).

DNA polymerase betas from liver and testes of cherry salmon, Oncorhynchus masou: purification and characterization of DNA polymerase betas with acidic isoelectric points

DNA polymerase betas from cherry salmon, Oncorhynchus masou, liver and testes were purified to near homogeneity, and no substantial differences between the enzymes were observed. The molecular weight of both enzymes, determined by SDS-polyacrylamide gel electrophoresis, was 39,000. The amino acid sequences of the N-terminus of the liver and testes enzymes were determined and compared with that of the rat enzyme. Of the N-terminal 30 amino acid residues of salmon liver DNA polymerase beta, 21 (70%) were identical to those of the rat enzyme sequence. However, unlike most eukaryotic DNA polymerase betas, the isoelectric points (pIs) of the DNA polymerase betas from salmon liver and testes were both estimated to be 6.2, which is significantly different from the alkaline isoelectric points (pI = 8.5-9.5) established for other highly purified vertebrate DNA polymerase betas. The cherry salmon DNA polymerase betas were still active at below 10 degrees C, compared with the rat enzyme.

[Chest wall reconstruction, relation between reconstruction method and infection]

We have operated 52 cases of chest wall resection in these 20 years. Twenty five cases in it were reconstructed by unabsorbable artificial materials such as Marlex mesh, Gore-Tex sheet and some others (Group 1). Eleven cases were covered with the net knitted by absorbable threads or muscle flaps (Group 2). Resting 16 cases have not received any definitive renovations (Group 3). Group 1 has suffered from such severe postoperative complications as acute empyema (8%) and chronic empyema (8%). Few cases in Group 2 has had infectious complication and ventilatory disturbance. Rate of postoperative vital capacity in Group 3 was the lowest value among three groups, though they had the smallest chest wall defects. We obtained following conclusions from this study. Every chest wall defect should be repaired by some way even if the defect were small. Chest wall defect in compromised host should be repaired by absorbable artificial material and muscle flap. Unabsorbable artificial materials are now indispensable for the reconstruction of large chest wall defect, however we must fully take care of postoperative infections in cases of its use.