Wakahiko Kishimoto

The Potential Role of Postoperative Hepatic Artery Chemotherapy in Patients with High-risk Hepatomas

The relationship between operative findings of hepatoma and the postoperative prognosis was studied to clarify indications for adjuvant hepatic arterial chemotherapy after hepatectomy. The results of adjuvant hepatic arterial chemotherapy using 0.4 mg/kg of doxorubicin and 0.12 mg/kg of mitomycin C and infusion of 5-fluorouracil were reported. One hundred sixty patients who had undergone hepatectomy for hepatoma were studied. In the operative findings of hepatoma, with a surgical margin of less than 10 mm, intrahepatic metastasis, tumor embolus in the second or more proximal branch of the portal vein, or lack of capsule formation related to the prognosis were the risk factors for recurrence. In 132 patients with these risk factors the survival rate of 19 patients with adjuvant arterial chemotherapy was significantly higher than for the 113 patients without it. Adjuvant hepatic arterial chemotherapy thus may be an effective therapy and should be studied prospectively in patients undergoing hepatectomy for high-risk hepatoma.

Detection of O2− generation and neutrophil accumulation in rat lungs after acute necrotizing pancreatitis

BACKGROUND Polymorphonuclear neutrophils (PMNs) and PMN-derived superoxide anions (O2-) have been found to mediate acute respiratory distress syndrome (ARDS). But the evidence has been obtained only indirectly, (for example, by treatment with free radical scavengers or by measuring lipid peroxides). METHODS We used chemiluminescence technique to measure O2- generation directly from the surface of rat lungs with necrotizing pancreatitis. Myeloperoxidase activity in the lung tissue was measured by a new chemiluminescence method to quantitate pulmonary neutrophil sequestration. RESULTS Transient bursts of chemiluminescence that reflected O2- generation were observed at the lung surface 3 to 5 hours after necrotizing pancreatitis was induced. No O2- dependent chemiluminescence was detected at the lung surfaces of the neutropenic rat made by pretreatment with polyclonal antineutrophil antibody. Myeloperoxidase activity was significantly high (mean, 1690 cell numbers/mg wet tissue) in the necrotizing pancreatitis rat lung (p < 0.005). CONCLUSIONS These data confirmed that activated neutrophils and neutrophil-derived superoxide anions were implicated in lung injury after acute severe pancreatitis.

LFA-1 (CD11a/CD18) and ICAM-1 (CD54) antibodies attenuate superoxide anion release from polymorphonuclear leukocytes in rats with experimental acute pancreatitis.

The inhibitive effects of anti-CD11a/CD18 (LFA-1) and anti-CD54 (ICAM-1) antibodies on the generation of superoxide anion (O−) by polymorphonuclear leukocytes (PMNs) was elucidated in rats induced with experimental acute pancreatitis. We investigated the generation of O2− by PMNs in two protocols: in the first, we measured the active oxygen-producing ability of PMNs isolated from blood in normal rats; in the second, we measured it from blood, peritoneal cavity, and bronchial alveolar lavage fluid in rats 3 h after the induction of pancreatitis. In normal rats, although LFA-1 antibody attenuated the generation of O2−, ICAM-1 antibody did not. However, in pancreatitis rats, both LFA-1 and ICAM-1 antibodies reduced the generation of O2− by PMNs isolated from blood and the peritoneal cavity. These results showed not only that both LFA-1 and ICAM-1 antibodies have a protective effect on the generation of O2−, but also that LFA-1 has a direct inhibitive effect on the generation of O2− by PMNs in this model. Furthermore, histological studies showed there to be less neutrophil accumulation in the lungs of LFA-1- and ICAM-1-treated animals compared to control animals.

Heparin effects on superoxide production by neutrophils.

Heparin is widely used in the treatment of various diseases, but the mechanisms of its biologic actions remain largely obscure. Recently, oxygen radicals, which are produced in a variety of conditions and cause tissue damage, have been implicated in the pathophysiology of various diseases. To investigate the relationship between heparin and oxygen radical production by neutrophils, we compared the effects of standard heparin (heparin sodium), which has been widely used, and a recently developed low molecular weight heparin (LMWH) which has potent anti-Xa activity, on neutrophil oxygen radical production in vitro. Standard heparin increased neutrophil oxygen radical production slightly at the low concentrations used clinically but reduced it at high concentrations, so that the effect of heparin on neutrophil oxygen radical production was biphasic. The effects of LMWH on neutrophil oxygen radical production were slight at both low and high concentrations. In disseminated intravascular coagulation (DIC) locally activated neutrophils produce oxygen radicals and have toxic effects in vivo. Thus we concluded that LMWH should be indicated for the treatment of DIC.

The involvement and sources of active oxygen in experimentally induced acute pancreatitis

The involvement of active oxygen has been suggested in the development of cerulein-induced acute pancreatitis in rats. Previously, we directly detected pancreatic active oxygen (O2−) production in rats with cerulein-induced pancreatitis by using a supersensitive photon counter and a cypridina luciferin analogue (MCLA) that reacts specifically with O2− by emitting luminescence. In the present study, with the specific aim of determining the source of O2−, we prepared two groups of animals with cerulein-induced pancreatitis: those treated with allopurinol, a xanthine oxidase inhibitor; and those treated with nitrogen mustard, a leukopenia-inducing substance. In each of these two groups, pancreatic O2− production and the severity of pancreatic injuries were comparatively studied. In the leukopenic animal group, decreases in O2− dependent chemiluminescence and improvement in the pancreatic condition coincided. This suggests that neutrophils might be involved in experimentally induced pancreatitis as a source of active oxygen.

Detection of superoxide free radicals in rats with acute pancreatitis.

To study the importance of oxygen-derived free radicals in acute pancreatitis, an experimental study of in vivo detection of superoxide free radicals (O2 −) was performed using rats. Using a new chemiluminescence probe (2-methyl-6-[p-methoxyphenyl]-3,7-dihydroimidazol[1,2-1]pyrazin-3-one; MCLA; a Cypridina luciferin analogue) and a highly sensitive photon counting system, O2− from the pancreatic surface of rats with experimental acute pancreatitis induced by 180 μg cedein/kg was detected. The time course of MCLA-dependent luminescence suggested that O2− production began 2–3 h after cerulein injection and then decreased gradually. Superoxide free radical production in the pancreas of rats with cerulein-induced acute pancreatitis was confirmed using MCLA-dependent chemiluminescence. This new method allows direct observation of the behavior of oxygen-derived free radicals.

Peritoneal absorption of pancreatic enzymes in bile‐induced acute pancreatitis in dogs

To clarify the contribution of peritoneal absorption of enzyme‐rich exudate to the persistent elevation of serum amylase in bile‐induced pancreatitis in dogs, serum amylase, lipase and immunoreactive trypsin (IRT) levels were measured during 24 h after induction of pancreatitis with and without peritoneal lavage. The basal level of serum amylase activity (m±s.e. = 1291 ± 111 U/L) reached a plateau at 30 min (2688 ± 185) after induction of pancreatitis and continued to rise until 24 h (7201 ± 424). This persistent amylase elevation could be reduced significantly by peritoneal lavage. Serum IRT rose to a peak (378 ± 103 ng/mL) at 30 min from the basal (20 ± 5), then decreased until 3 h (211 ± 34) and maintained a consistent level thereafter. Serum lipase elevation took an intermediate course between the levels of serum amylase and IRT. Intraperitoneal injection of 5 mL pancreatic juice could reproduce similar elevations to those of the respective enzymes, except lipase, seen in pancreatitis. These results suggest that transperitoneal absorption of pancreatic enzymes contributes to the elevation in serum enzyme levels and that rates of peritoneal absorption and serum disappearance differ from enzyme to enzyme.

The ability of polymorphonuclear leukocytes to produce active oxygen in a model of peritonitis in rats.

To elucidate the mechanism of enhancing survival in peritonitis rats treated with lentinan, a fully purified beta-1,3-glucan, we measured the active oxygen-producing ability of polymorphonuclear leukocytes (PMNs). Four groups of rats (group I, fecal peritonitis control; II, rats receiving 3 mg/kg lentinan intraperitoneally at the same time as peritonitis induction; III, rats receiving 1 mg/kg gentamicin intramuscularly; and IV, rats receiving combined lentinan-gentamicin treatment) were used. The survival period was significantly longer in group IV than in the other three groups. The ability of ascitic PMNs to produce active oxygen (superoxide, H2O2, myeloperoxidase) was significantly more than that of blood PMNs in each group at 20 h after peritonitis induction. The increase in active oxygen production in ascitic PMNs was higher in group IV compared with that in the other three groups. The concentration of lentinan in the blood was high at 24 h after administering lentinan intraperitoneally to both the normal and peritonitis rats. In the in vitro study, the superoxide production in normal rat blood PMNs was significantly higher in the presence of cytokines (IL-1 beta, IL-6, TNF-alpha) without dose-dependence but was not higher for the lentinan group than in the control. This study therefore suggests that lentinan activated the peritoneal macrophage secretory activity and produced cytokines which thus enhanced the ability of PMNs to produce active oxygen, which possesses a bactericidal ability in PMNs.

Decreased production of active oxygen species by neutrophils in patients with liver cirrhosis and hepatocellular carcinoma

SummaryAdult respiratory distress syndrome (ARDS) following infection is one of the postoperative complications of hepatectomy of cirrhosis. In this study we focused on the anti-microbial activity of nertrophils. We measured production of active oxygen species by neutrophils, and simultaneously examined their nutritional status, immunity and ICG (K-ICG) disappearance ratio. When compared to the controls, the patients with cirrhosis had siginificantly lower production of O2- upon stimulation by N-formyl-Met-Lue Phe (fMLP) or opsonic aymosan (OZ). The presence of cancer did not affect results for the groups studied. Overall H2O2 production was lower in cirrhotic patients than in controls. There was a positive coorelation between O2- production and K-ICG, which was used to estimate the severity of cirrhosis. Indicators of nutrition and immunity were slso lower in currhotic patients, but neither of these indicators correlated with the production of active oxygen specis. From these results, we concluded that the production of active oxygen species by neutrophils is lower in cirrhotic patients than in controls. Moreover, this decline correlates with the severity of cirrhosis.

Results of hepatic resection and postoperative arterial chemotherapy for hepatocellular carcinoma

SummaryTo improve the outcome of patients who had undergone hepatic resection for hepatocellular carcinoma (HCC), we employed postoperative adjuvant hepatic arterial infusion chemotherapy (AHAI) in 23 patients. Patients showing various risk factors for the recurrence of HCC were given one shot of doxorubicin and mitomycin C suspended in an oily medium (lipiodol) and an infusion of 5-fluorouracil. The 3-year survival value calculated for patients who were treated with AHAI was 75%, which was significantly higher than that found for patients who did not receive AHAI (n=156;P<0.05). In addition, among the patients who underwent hepatic lobectomy, the survival of those who received AHAI was also significantly greater than that of those who did not (n=46;P<0.01). AHAI did not cause any severe complications. These results indicate that AHAI may be an effective therapy for patients with HCC.